/* APPLE LOCAL begin LLVM (ENTIRE FILE!) */
/* High-level LLVM backend interface
Copyright (C) 2005, 2006, 2007 Free Software Foundation, Inc.
Contributed by Chris Lattner (sabre@nondot.org)
This file is part of GCC.
GCC is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free
Software Foundation; either version 2, or (at your option) any later
version.
GCC is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
for more details.
You should have received a copy of the GNU General Public License
along with GCC; see the file COPYING. If not, write to the Free
Software Foundation, 59 Temple Place - Suite 330, Boston, MA
02111-1307, USA. */
//===----------------------------------------------------------------------===//
// This is the code that converts GCC AST nodes into LLVM code.
//===----------------------------------------------------------------------===//
#include "llvm/ValueSymbolTable.h"
#include "llvm-abi.h"
#include "llvm-internal.h"
#include "llvm-debug.h"
#include "llvm/CallingConv.h"
#include "llvm/Constants.h"
#include "llvm/DerivedTypes.h"
#include "llvm/InlineAsm.h"
#include "llvm/Instructions.h"
#include "llvm/Module.h"
#include "llvm/Analysis/ConstantFolding.h"
#include "llvm/Target/TargetAsmInfo.h"
#include "llvm/Target/TargetData.h"
#include "llvm/Target/TargetMachine.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/ADT/DenseMap.h"
#include <iostream>
extern "C" {
#include "config.h"
#include "system.h"
#include "coretypes.h"
#include "tm.h"
#include "tm_p.h"
#include "tree.h"
#include "c-tree.h" // FIXME: eliminate.
#include "tree-iterator.h"
#include "output.h"
#include "diagnostic.h"
#include "real.h"
#include "langhooks.h"
#include "function.h"
#include "toplev.h"
#include "flags.h"
#include "target.h"
#include "hard-reg-set.h"
#include "except.h"
#include "rtl.h"
extern bool tree_could_throw_p(tree); // tree-flow.h uses non-C++ C constructs.
extern int get_pointer_alignment (tree exp, unsigned int max_align);
extern enum machine_mode reg_raw_mode[FIRST_PSEUDO_REGISTER];
}
#define ITANIUM_STYLE_EXCEPTIONS
//===----------------------------------------------------------------------===//
// Matching LLVM Values with GCC DECL trees
//===----------------------------------------------------------------------===//
//
// LLVMValues is a vector of LLVM Values. GCC tree nodes keep track of LLVM
// Values using this vector's index. It is easier to save and restore the index
// than the LLVM Value pointer while usig PCH.
// Collection of LLVM Values
static std::vector<Value *> LLVMValues;
typedef DenseMap<Value *, unsigned> LLVMValuesMapTy;
static LLVMValuesMapTy LLVMValuesMap;
// Remember the LLVM value for GCC tree node.
void llvm_set_decl(tree Tr, Value *V) {
// If there is not any value then do not add new LLVMValues entry.
// However clear Tr index if it is non zero.
if (!V) {
if (GET_DECL_LLVM_INDEX(Tr))
SET_DECL_LLVM_INDEX(Tr, 0);
return;
}
unsigned &ValueSlot = LLVMValuesMap[V];
if (ValueSlot) {
// Already in map
SET_DECL_LLVM_INDEX(Tr, ValueSlot);
return;
}
unsigned Index = LLVMValues.size() + 1;
LLVMValues.push_back(V);
SET_DECL_LLVM_INDEX(Tr, Index);
LLVMValuesMap[V] = Index;
}
// Return TRUE if there is a LLVM Value associate with GCC tree node.
bool llvm_set_decl_p(tree Tr) {
unsigned Index = GET_DECL_LLVM_INDEX(Tr);
if (Index == 0)
return false;
if (LLVMValues[Index - 1])
return true;
return false;
}
// Get LLVM Value for the GCC tree node based on LLVMValues vector index.
// If there is not any value associated then use make_decl_llvm() to
// make LLVM value. When GCC tree node is initialized, it has 0 as the
// index value. This is why all recorded indices are offset by 1.
Value *llvm_get_decl(tree Tr) {
unsigned Index = GET_DECL_LLVM_INDEX(Tr);
if (Index == 0) {
make_decl_llvm(Tr);
Index = GET_DECL_LLVM_INDEX(Tr);
// If there was an error, we may have disabled creating LLVM values.
if (Index == 0) return 0;
}
assert ((Index - 1) < LLVMValues.size() && "Invalid LLVM value index");
assert (LLVMValues[Index - 1] && "Trying to use deleted LLVM value!");
return LLVMValues[Index - 1];
}
/// changeLLVMValue - If Old exists in the LLVMValues map, rewrite it to New.
/// At this point we know that New is not in the map.
void changeLLVMValue(Value *Old, Value *New) {
assert(!LLVMValuesMap.count(New) && "New cannot be in the map!");
// Find Old in the table.
LLVMValuesMapTy::iterator I = LLVMValuesMap.find(Old);
if (I == LLVMValuesMap.end()) return;
unsigned Idx = I->second-1;
assert(Idx < LLVMValues.size() && "Out of range index!");
assert(LLVMValues[Idx] == Old && "Inconsistent LLVMValues mapping!");
LLVMValues[Idx] = New;
// Remove the old value from the value map.
LLVMValuesMap.erase(I);
// Insert the new value into the value map. We know that it can't already
// exist in the mapping.
if (New)
LLVMValuesMap[New] = Idx+1;
}
// Read LLVM Types string table
void readLLVMValues() {
GlobalValue *V = TheModule->getNamedGlobal("llvm.pch.values");
if (!V)
return;
GlobalVariable *GV = cast<GlobalVariable>(V);
ConstantStruct *ValuesFromPCH = cast<ConstantStruct>(GV->getOperand(0));
for (unsigned i = 0; i < ValuesFromPCH->getNumOperands(); ++i) {
Value *Va = ValuesFromPCH->getOperand(i);
if (!Va) {
// If V is empty then nsert NULL to represent empty entries.
LLVMValues.push_back(Va);
continue;
}
if (ConstantArray *CA = dyn_cast<ConstantArray>(Va)) {
std::string Str = CA->getAsString();
Va = TheModule->getValueSymbolTable().lookup(Str);
}
assert (Va != NULL && "Invalid Value in LLVMValues string table");
LLVMValues.push_back(Va);
}
// Now, llvm.pch.values is not required so remove it from the symbol table.
GV->eraseFromParent();
}
// GCC tree's uses LLVMValues vector's index to reach LLVM Values.
// Create a string table to hold these LLVM Values' names. This string
// table will be used to recreate LTypes vector after loading PCH.
void writeLLVMValues() {
if (LLVMValues.empty())
return;
std::vector<Constant *> ValuesForPCH;
for (std::vector<Value *>::iterator I = LLVMValues.begin(),
E = LLVMValues.end(); I != E; ++I) {
if (Constant *C = dyn_cast_or_null<Constant>(*I))
ValuesForPCH.push_back(C);
else
// Non constant values, e.g. arguments, are not at global scope.
// When PCH is read, only global scope values are used.
ValuesForPCH.push_back(Constant::getNullValue(Type::Int32Ty));
}
// Create string table.
Constant *LLVMValuesTable = ConstantStruct::get(ValuesForPCH, false);
// Create variable to hold this string table.
new GlobalVariable(LLVMValuesTable->getType(), true,
GlobalValue::ExternalLinkage,
LLVMValuesTable,
"llvm.pch.values", TheModule);
}
/// eraseLocalLLVMValues - drop all non-global values from the LLVM values map.
void eraseLocalLLVMValues() {
// Try to reduce the size of LLVMValues by removing local values from the end.
std::vector<Value *>::reverse_iterator I, E;
for (I = LLVMValues.rbegin(), E = LLVMValues.rend(); I != E; ++I) {
if (Value *V = *I) {
if (isa<Constant>(V))
break;
else
LLVMValuesMap.erase(V);
}
}
LLVMValues.erase(I.base(), LLVMValues.end()); // Drop erased values
// Iterate over LLVMValuesMap since it may be much smaller than LLVMValues.
for (LLVMValuesMapTy::iterator I = LLVMValuesMap.begin(),
E = LLVMValuesMap.end(); I != E; ++I) {
assert(I->first && "Values map contains NULL!");
if (!isa<Constant>(I->first)) {
unsigned Index = I->second - 1;
assert(Index < LLVMValues.size() && LLVMValues[Index] == I->first &&
"Inconsistent value map!");
LLVMValues[Index] = NULL;
LLVMValuesMap.erase(I);
}
}
}
/// isGCC_SSA_Temporary - Return true if this is an SSA temporary that we can
/// directly compile into an LLVM temporary. This saves us from creating an
/// alloca and creating loads/stores of that alloca (a compile-time win). We
/// can only do this if the value is a first class llvm value and if it's a
/// "gimple_formal_tmp_var".
static bool isGCC_SSA_Temporary(tree decl) {
return TREE_CODE(decl) == VAR_DECL &&
DECL_GIMPLE_FORMAL_TEMP_P(decl) && !TREE_ADDRESSABLE(decl) &&
!isAggregateTreeType(TREE_TYPE(decl));
}
/// isStructWithVarSizeArrayAtEnd - Return true if this StructType contains a
/// zero sized array as its last element. This typically happens due to C
/// constructs like: struct X { int A; char B[]; };
static bool isStructWithVarSizeArrayAtEnd(const Type *Ty) {
const StructType *STy = dyn_cast<StructType>(Ty);
if (STy == 0) return false;
assert(STy->getNumElements() && "empty struct?");
const Type *LastElTy = STy->getElementType(STy->getNumElements()-1);
return isa<ArrayType>(LastElTy) &&
cast<ArrayType>(LastElTy)->getNumElements() == 0;
}
/// getINTEGER_CSTVal - Return the specified INTEGER_CST value as a uint64_t.
///
static uint64_t getINTEGER_CSTVal(tree exp) {
unsigned HOST_WIDE_INT HI = (unsigned HOST_WIDE_INT)TREE_INT_CST_HIGH(exp);
unsigned HOST_WIDE_INT LO = (unsigned HOST_WIDE_INT)TREE_INT_CST_LOW(exp);
if (HOST_BITS_PER_WIDE_INT == 64) {
return (uint64_t)LO;
} else {
assert(HOST_BITS_PER_WIDE_INT == 32 &&
"Only 32- and 64-bit hosts supported!");
return ((uint64_t)HI << 32) | (uint64_t)LO;
}
}
/// isInt64 - Return true if t is an INTEGER_CST that fits in a 64 bit integer.
/// If Unsigned is false, returns whether it fits in a int64_t. If Unsigned is
/// true, returns whether the value is non-negative and fits in a uint64_t.
/// Always returns false for overflowed constants.
bool isInt64(tree_node *t, bool Unsigned) {
if (HOST_BITS_PER_WIDE_INT == 64)
return host_integerp(t, Unsigned);
else {
assert(HOST_BITS_PER_WIDE_INT == 32 &&
"Only 32- and 64-bit hosts supported!");
return
(TREE_CODE (t) == INTEGER_CST && !TREE_OVERFLOW (t))
&& ((TYPE_UNSIGNED(TREE_TYPE(t)) == Unsigned) ||
// If the constant is signed and we want an unsigned result, check
// that the value is non-negative. If the constant is unsigned and
// we want a signed result, check it fits in 63 bits.
(HOST_WIDE_INT)TREE_INT_CST_HIGH(t) >= 0);
}
}
/// getInt64 - Extract the value of an INTEGER_CST as a 64 bit integer. If
/// Unsigned is false, the value must fit in a int64_t. If Unsigned is true,
/// the value must be non-negative and fit in a uint64_t. Must not be used on
/// overflowed constants. These conditions can be checked by calling isInt64.
uint64_t getInt64(tree_node *t, bool Unsigned) {
assert(isInt64(t, Unsigned) && "invalid constant!");
return getINTEGER_CSTVal(t);
}
//===----------------------------------------------------------------------===//
// ... High-Level Methods ...
//===----------------------------------------------------------------------===//
/// TheTreeToLLVM - Keep track of the current function being compiled. This is
/// only to support the address of labels extension.
static TreeToLLVM *TheTreeToLLVM = 0;
const TargetData &getTargetData() {
return *TheTarget->getTargetData();
}
TreeToLLVM::TreeToLLVM(tree fndecl) : TD(getTargetData()) {
FnDecl = fndecl;
Fn = 0;
ReturnBB = UnwindBB = 0;
if (TheDebugInfo) {
expanded_location Location = expand_location(DECL_SOURCE_LOCATION (fndecl));
if (Location.file) {
TheDebugInfo->setLocationFile(Location.file);
TheDebugInfo->setLocationLine(Location.line);
} else {
TheDebugInfo->setLocationFile("<unknown file>");
TheDebugInfo->setLocationLine(0);
}
}
AllocaInsertionPoint = 0;
CleanupFilter = NULL_TREE;
ExceptionValue = 0;
ExceptionSelectorValue = 0;
FuncEHException = 0;
FuncEHSelector = 0;
FuncEHGetTypeID = 0;
FuncCPPPersonality = 0;
FuncUnwindResume = 0;
NumAddressTakenBlocks = 0;
IndirectGotoBlock = 0;
CurrentEHScopes.reserve(16);
assert(TheTreeToLLVM == 0 && "Reentering function creation?");
TheTreeToLLVM = this;
}
TreeToLLVM::~TreeToLLVM() {
TheTreeToLLVM = 0;
}
namespace {
/// FunctionPrologArgumentConversion - This helper class is driven by the ABI
/// definition for this target to figure out how to retrieve arguments from
/// the stack/regs coming into a function and store them into an appropriate
/// alloca for the argument.
struct FunctionPrologArgumentConversion : public DefaultABIClient {
tree FunctionDecl;
Function::arg_iterator &AI;
LLVMBuilder Builder;
std::vector<Value*> LocStack;
std::vector<std::string> NameStack;
FunctionPrologArgumentConversion(tree FnDecl,
Function::arg_iterator &ai,
const LLVMBuilder &B)
: FunctionDecl(FnDecl), AI(ai), Builder(B) {}
void setName(const std::string &Name) {
NameStack.push_back(Name);
}
void setLocation(Value *Loc) {
LocStack.push_back(Loc);
}
void clear() {
assert(NameStack.size() == 1 && LocStack.size() == 1 && "Imbalance!");
NameStack.clear();
LocStack.clear();
}
void HandleAggregateShadowArgument(const PointerType *PtrArgTy,
bool RetPtr) {
// If the function returns a structure by value, we transform the function
// to take a pointer to the result as the first argument of the function
// instead.
assert(AI != Builder.GetInsertBlock()->getParent()->arg_end() &&
"No explicit return value?");
AI->setName("agg.result");
tree ResultDecl = DECL_RESULT(FunctionDecl);
tree RetTy = TREE_TYPE(TREE_TYPE(FunctionDecl));
if (TREE_CODE(RetTy) == TREE_CODE(TREE_TYPE(ResultDecl))) {
SET_DECL_LLVM(ResultDecl, AI);
++AI;
return;
}
// Otherwise, this must be something returned with NRVO.
assert(TREE_CODE(TREE_TYPE(ResultDecl)) == REFERENCE_TYPE &&
"Not type match and not passing by reference?");
// Create an alloca for the ResultDecl.
Value *Tmp = TheTreeToLLVM->CreateTemporary(AI->getType());
Builder.CreateStore(AI, Tmp);
SET_DECL_LLVM(ResultDecl, Tmp);
if (TheDebugInfo) {
TheDebugInfo->EmitDeclare(ResultDecl,
llvm::dwarf::DW_TAG_return_variable,
"agg.result", RetTy, Tmp,
Builder.GetInsertBlock());
}
++AI;
}
void HandleScalarArgument(const llvm::Type *LLVMTy, tree type) {
Value *ArgVal = AI;
if (ArgVal->getType() != LLVMTy) {
if (isa<PointerType>(ArgVal->getType()) && isa<PointerType>(LLVMTy)) {
// If this is GCC being sloppy about pointer types, insert a bitcast.
// See PR1083 for an example.
ArgVal = Builder.CreateBitCast(ArgVal, LLVMTy, "tmp");
} else if (ArgVal->getType() == Type::DoubleTy) {
// If this is a K&R float parameter, it got promoted to double. Insert
// the truncation to float now.
ArgVal = Builder.CreateFPTrunc(ArgVal, LLVMTy,
NameStack.back().c_str());
} else {
// If this is just a mismatch between integer types, this is due
// to K&R prototypes, where the forward proto defines the arg as int
// and the actual impls is a short or char.
assert(ArgVal->getType() == Type::Int32Ty && LLVMTy->isInteger() &&
"Lowerings don't match?");
ArgVal = Builder.CreateTrunc(ArgVal, LLVMTy,NameStack.back().c_str());
}
}
assert(!LocStack.empty());
Value *Loc = LocStack.back();
if (cast<PointerType>(Loc->getType())->getElementType() != LLVMTy)
// This cast only involves pointers, therefore BitCast
Loc = Builder.CreateBitCast(Loc, PointerType::get(LLVMTy), "tmp");
Builder.CreateStore(ArgVal, Loc);
AI->setName(NameStack.back());
++AI;
}
void EnterField(unsigned FieldNo, const llvm::Type *StructTy) {
NameStack.push_back(NameStack.back()+"."+utostr(FieldNo));
Value *Loc = LocStack.back();
if (cast<PointerType>(Loc->getType())->getElementType() != StructTy)
// This cast only involves pointers, therefore BitCast
Loc = Builder.CreateBitCast(Loc, PointerType::get(StructTy), "tmp");
Value *Idxs[] = {
Constant::getNullValue(Type::Int32Ty),
ConstantInt::get(Type::Int32Ty, FieldNo)
};
Loc = Builder.CreateGEP(Loc, Idxs, Idxs + 2, "tmp");
LocStack.push_back(Loc);
}
void ExitField() {
NameStack.pop_back();
LocStack.pop_back();
}
};
}
void TreeToLLVM::StartFunctionBody() {
const char *Name = "";
// Get the name of the function.
if (tree ID = DECL_ASSEMBLER_NAME(FnDecl))
Name = IDENTIFIER_POINTER(ID);
// Determine the FunctionType and calling convention for this function.
tree static_chain = cfun->static_chain_decl;
const FunctionType *FTy;
unsigned CallingConv;
// If the function has no arguments and is varargs (...), turn it into a
// non-varargs function by scanning the param list for the function. This
// allows C functions declared as "T foo() {}" to be treated like
// "T foo(void) {}" and allows us to handle functions with K&R-style
// definitions correctly.
if (TYPE_ARG_TYPES(TREE_TYPE(FnDecl)) == 0) {
FTy = TheTypeConverter->ConvertArgListToFnType(TREE_TYPE(TREE_TYPE(FnDecl)),
DECL_ARGUMENTS(FnDecl),
static_chain,
CallingConv);
#ifdef TARGET_ADJUST_LLVM_CC
TARGET_ADJUST_LLVM_CC(CallingConv, TREE_TYPE(FnDecl));
#endif
} else {
// Otherwise, just get the type from the function itself.
FTy = TheTypeConverter->ConvertFunctionType(TREE_TYPE(FnDecl),
FnDecl,
static_chain,
CallingConv);
}
// If we've already seen this function and created a prototype, and if the
// proto has the right LLVM type, just use it.
if (DECL_LLVM_SET_P(FnDecl) &&
cast<PointerType>(DECL_LLVM(FnDecl)->getType())->getElementType() == FTy){
Fn = cast<Function>(DECL_LLVM(FnDecl));
assert(Fn->getCallingConv() == CallingConv &&
"Calling convention disagreement between prototype and impl!");
// The visibility can be changed from the last time we've seen this
// function. Set to current.
if (TREE_PUBLIC(FnDecl)) {
if (DECL_VISIBILITY(FnDecl) == VISIBILITY_HIDDEN)
Fn->setVisibility(Function::HiddenVisibility);
else if (DECL_VISIBILITY(FnDecl) == VISIBILITY_PROTECTED)
Fn->setVisibility(Function::ProtectedVisibility);
else if (DECL_VISIBILITY(FnDecl) == VISIBILITY_DEFAULT)
Fn->setVisibility(Function::DefaultVisibility);
}
} else {
Function *FnEntry = TheModule->getFunction(Name);
if (FnEntry) {
assert(FnEntry->getName() == Name && "Same entry, different name?");
assert(FnEntry->isDeclaration() &&
"Multiple fns with same name and neither are external!");
FnEntry->setName(""); // Clear name to avoid conflicts.
assert(FnEntry->getCallingConv() == CallingConv &&
"Calling convention disagreement between prototype and impl!");
}
// Otherwise, either it exists with the wrong type or it doesn't exist. In
// either case create a new function.
Fn = new Function(FTy, Function::ExternalLinkage, Name, TheModule);
assert(Fn->getName() == Name && "Preexisting fn with the same name!");
Fn->setCallingConv(CallingConv);
// If a previous proto existed with the wrong type, replace any uses of it
// with the actual function and delete the proto.
if (FnEntry) {
FnEntry->replaceAllUsesWith(ConstantExpr::getBitCast(Fn,
FnEntry->getType()));
changeLLVMValue(FnEntry, Fn);
FnEntry->eraseFromParent();
}
SET_DECL_LLVM(FnDecl, Fn);
}
// The function should not already have a body.
assert(Fn->empty() && "Function expanded multiple times!");
// Compute the linkage that the function should get.
if (!TREE_PUBLIC(FnDecl) /*|| lang_hooks.llvm_is_in_anon(subr)*/) {
Fn->setLinkage(Function::InternalLinkage);
} else if (DECL_COMDAT(FnDecl)) {
Fn->setLinkage(Function::LinkOnceLinkage);
} else if (DECL_WEAK(FnDecl) || DECL_ONE_ONLY(FnDecl)) {
Fn->setLinkage(Function::WeakLinkage);
}
#ifdef TARGET_ADJUST_LLVM_LINKAGE
TARGET_ADJUST_LLVM_LINKAGE(Fn,FnDecl);
#endif /* TARGET_ADJUST_LLVM_LINKAGE */
// Handle visibility style
if (TREE_PUBLIC(FnDecl)) {
if (DECL_VISIBILITY(FnDecl) == VISIBILITY_HIDDEN)
Fn->setVisibility(Function::HiddenVisibility);
else if (DECL_VISIBILITY(FnDecl) == VISIBILITY_PROTECTED)
Fn->setVisibility(Function::ProtectedVisibility);
}
// Handle functions in specified sections.
if (DECL_SECTION_NAME(FnDecl))
Fn->setSection(TREE_STRING_POINTER(DECL_SECTION_NAME(FnDecl)));
// Handle used Functions
if (DECL_PRESERVE_P (FnDecl))
AttributeUsedGlobals.insert(Fn);
// Handle noinline Functions
if (lookup_attribute ("noinline", DECL_ATTRIBUTES (FnDecl))) {
const Type *SBP= PointerType::get(Type::Int8Ty);
AttributeNoinlineFunctions.push_back(ConstantExpr::getBitCast(Fn,SBP));
}
// Handle annotate attributes
if (DECL_ATTRIBUTES(FnDecl))
AddAnnotateAttrsToGlobal(Fn, FnDecl);
// Create a new basic block for the function.
Builder.SetInsertPoint(new BasicBlock("entry", Fn));
if (TheDebugInfo)
TheDebugInfo->EmitFunctionStart(FnDecl, Fn, Builder.GetInsertBlock());
// Loop over all of the arguments to the function, setting Argument names and
// creating argument alloca's for the PARM_DECLs in case their address is
// exposed.
Function::arg_iterator AI = Fn->arg_begin();
// Rename and alloca'ify real arguments.
FunctionPrologArgumentConversion Client(FnDecl, AI, Builder);
TheLLVMABI<FunctionPrologArgumentConversion> ABIConverter(Client);
// Handle the DECL_RESULT.
ABIConverter.HandleReturnType(TREE_TYPE(TREE_TYPE(FnDecl)));
// Prepend the static chain (if any) to the list of arguments.
tree Args = static_chain ? static_chain : DECL_ARGUMENTS(FnDecl);
while (Args) {
const char *Name = "unnamed_arg";
if (DECL_NAME(Args)) Name = IDENTIFIER_POINTER(DECL_NAME(Args));
if (isPassedByInvisibleReference(TREE_TYPE(Args))) {
// If the value is passed by 'invisible reference', the l-value for the
// argument IS the argument itself.
SET_DECL_LLVM(Args, AI);
AI->setName(Name);
++AI;
} else {
// Otherwise, we create an alloca to hold the argument value and provide
// an l-value. On entry to the function, we copy formal argument values
// into the alloca.
const Type *ArgTy = ConvertType(TREE_TYPE(Args));
Value *Tmp = CreateTemporary(ArgTy);
Tmp->setName(std::string(Name)+"_addr");
SET_DECL_LLVM(Args, Tmp);
if (TheDebugInfo) {
TheDebugInfo->EmitDeclare(Args, llvm::dwarf::DW_TAG_arg_variable,
Name, TREE_TYPE(Args), Tmp,
Builder.GetInsertBlock());
}
// Emit annotate intrinsic if arg has annotate attr
if (DECL_ATTRIBUTES(Args))
EmitAnnotateIntrinsic(Tmp, Args);
Client.setName(Name);
Client.setLocation(Tmp);
ABIConverter.HandleArgument(TREE_TYPE(Args));
Client.clear();
}
Args = Args == static_chain ? DECL_ARGUMENTS(FnDecl) : TREE_CHAIN(Args);
}
// If this is not a void-returning function, initialize the RESULT_DECL.
if (DECL_RESULT(FnDecl) && !VOID_TYPE_P(TREE_TYPE(DECL_RESULT(FnDecl))) &&
!DECL_LLVM_SET_P(DECL_RESULT(FnDecl)))
EmitAutomaticVariableDecl(DECL_RESULT(FnDecl));
// If this function has nested functions, we should handle a potential
// nonlocal_goto_save_area.
if (cfun->nonlocal_goto_save_area) {
// Not supported yet.
}
// As it turns out, not all temporaries are associated with blocks. For those
// that aren't, emit them now.
for (tree t = cfun->unexpanded_var_list; t; t = TREE_CHAIN(t)) {
assert(!DECL_LLVM_SET_P(TREE_VALUE(t)) && "var already emitted?");
EmitAutomaticVariableDecl(TREE_VALUE(t));
}
// Create a new block for the return node, but don't insert it yet.
ReturnBB = new BasicBlock("return");
}
Function *TreeToLLVM::FinishFunctionBody() {
// Insert the return block at the end of the function.
EmitBlock(ReturnBB);
Value *RetVal = 0;
// If the function returns a value, get it into a register and return it now.
if (Fn->getReturnType() != Type::VoidTy) {
if (!isAggregateTreeType(TREE_TYPE(DECL_RESULT(FnDecl)))) {
// If the DECL_RESULT is a scalar type, just load out the return value
// and return it.
tree TreeRetVal = DECL_RESULT(FnDecl);
RetVal = Builder.CreateLoad(DECL_LLVM(TreeRetVal), "retval");
bool RetValSigned = !TYPE_UNSIGNED(TREE_TYPE(TreeRetVal));
Instruction::CastOps opcode = CastInst::getCastOpcode(
RetVal, RetValSigned, Fn->getReturnType(), RetValSigned);
RetVal = CastToType(opcode, RetVal, Fn->getReturnType());
} else {
// Otherwise, this aggregate result must be something that is returned in
// a scalar register for this target. We must bit convert the aggregate
// to the specified scalar type, which we do by casting the pointer and
// loading.
RetVal = BitCastToType(DECL_LLVM(DECL_RESULT(FnDecl)),
PointerType::get(Fn->getReturnType()));
RetVal = Builder.CreateLoad(RetVal, "retval");
}
}
if (TheDebugInfo) TheDebugInfo->EmitRegionEnd(Fn, Builder.GetInsertBlock());
Builder.CreateRet(RetVal);
// If this function has exceptions, emit the lazily created unwind block.
if (UnwindBB) {
EmitBlock(UnwindBB);
#ifdef ITANIUM_STYLE_EXCEPTIONS
if (ExceptionValue) {
// Fetch and store exception handler.
Value *Arg = Builder.CreateLoad(ExceptionValue, "eh_ptr");
Builder.CreateCall(FuncUnwindResume, Arg);
Builder.CreateUnreachable();
} else {
new UnwindInst(UnwindBB);
}
#else
new UnwindInst(UnwindBB);
#endif
}
// If this function takes the address of a label, emit the indirect goto
// block.
if (IndirectGotoBlock) {
EmitBlock(IndirectGotoBlock);
// Change the default destination to go to one of the other destinations, if
// there is any other dest.
SwitchInst *SI = cast<SwitchInst>(IndirectGotoBlock->getTerminator());
if (SI->getNumSuccessors() > 1)
SI->setSuccessor(0, SI->getSuccessor(1));
}
// Remove any cached LLVM values that are local to this function. Such values
// may be deleted when the optimizers run, so would be dangerous to keep.
eraseLocalLLVMValues();
return Fn;
}
Value *TreeToLLVM::Emit(tree exp, Value *DestLoc) {
assert((isAggregateTreeType(TREE_TYPE(exp)) == (DestLoc != 0) ||
TREE_CODE(exp) == MODIFY_EXPR) &&
"Didn't pass DestLoc to an aggregate expr, or passed it to scalar!");
Value *Result = 0;
if (TheDebugInfo) {
if (EXPR_HAS_LOCATION(exp)) {
// Set new location on the way up the tree.
TheDebugInfo->setLocationFile(EXPR_FILENAME(exp));
TheDebugInfo->setLocationLine(EXPR_LINENO(exp));
}
// These node create an artificial jump to end of block.
if (TREE_CODE(exp) != BIND_EXPR && TREE_CODE(exp) != STATEMENT_LIST)
TheDebugInfo->EmitStopPoint(Fn, Builder.GetInsertBlock());
}
switch (TREE_CODE(exp)) {
default:
std::cerr << "Unhandled expression!\n";
debug_tree(exp);
abort();
// Basic lists and binding scopes
case BIND_EXPR: Result = EmitBIND_EXPR(exp, DestLoc); break;
case STATEMENT_LIST: Result = EmitSTATEMENT_LIST(exp, DestLoc); break;
// Control flow
case LABEL_EXPR: Result = EmitLABEL_EXPR(exp); break;
case GOTO_EXPR: Result = EmitGOTO_EXPR(exp); break;
case RETURN_EXPR: Result = EmitRETURN_EXPR(exp, DestLoc); break;
case COND_EXPR: Result = EmitCOND_EXPR(exp); break;
case SWITCH_EXPR: Result = EmitSWITCH_EXPR(exp); break;
case TRY_FINALLY_EXPR:
case TRY_CATCH_EXPR: Result = EmitTRY_EXPR(exp); break;
case EXC_PTR_EXPR: Result = EmitEXC_PTR_EXPR(exp); break;
case CATCH_EXPR: Result = EmitCATCH_EXPR(exp); break;
case EH_FILTER_EXPR: Result = EmitEH_FILTER_EXPR(exp); break;
// Expressions
case VAR_DECL:
case PARM_DECL:
case RESULT_DECL:
case INDIRECT_REF:
case ARRAY_REF:
case ARRAY_RANGE_REF:
case COMPONENT_REF:
case BIT_FIELD_REF:
case STRING_CST:
case REALPART_EXPR:
case IMAGPART_EXPR:
Result = EmitLoadOfLValue(exp, DestLoc);
break;
case OBJ_TYPE_REF: Result = EmitOBJ_TYPE_REF(exp); break;
case ADDR_EXPR: Result = EmitADDR_EXPR(exp); break;
case CALL_EXPR: Result = EmitCALL_EXPR(exp, DestLoc); break;
case MODIFY_EXPR: Result = EmitMODIFY_EXPR(exp, DestLoc); break;
case ASM_EXPR: Result = EmitASM_EXPR(exp); break;
case NON_LVALUE_EXPR: Result = Emit(TREE_OPERAND(exp, 0), DestLoc); break;
// Unary Operators
case NOP_EXPR: Result = EmitNOP_EXPR(exp, DestLoc); break;
case FIX_TRUNC_EXPR:
case FLOAT_EXPR:
case CONVERT_EXPR: Result = EmitCONVERT_EXPR(exp, DestLoc); break;
case VIEW_CONVERT_EXPR: Result = EmitVIEW_CONVERT_EXPR(exp, DestLoc); break;
case NEGATE_EXPR: Result = EmitNEGATE_EXPR(exp, DestLoc); break;
case CONJ_EXPR: Result = EmitCONJ_EXPR(exp, DestLoc); break;
case ABS_EXPR: Result = EmitABS_EXPR(exp); break;
case BIT_NOT_EXPR: Result = EmitBIT_NOT_EXPR(exp); break;
case TRUTH_NOT_EXPR: Result = EmitTRUTH_NOT_EXPR(exp); break;
// Binary Operators
case LT_EXPR:
Result = EmitCompare(exp, ICmpInst::ICMP_ULT, ICmpInst::ICMP_SLT,
FCmpInst::FCMP_OLT);
break;
case LE_EXPR:
Result = EmitCompare(exp, ICmpInst::ICMP_ULE, ICmpInst::ICMP_SLE,
FCmpInst::FCMP_OLE);
break;
case GT_EXPR:
Result = EmitCompare(exp, ICmpInst::ICMP_UGT, ICmpInst::ICMP_SGT,
FCmpInst::FCMP_OGT);
break;
case GE_EXPR:
Result = EmitCompare(exp, ICmpInst::ICMP_UGE, ICmpInst::ICMP_SGE,
FCmpInst::FCMP_OGE);
break;
case EQ_EXPR:
Result = EmitCompare(exp, ICmpInst::ICMP_EQ, ICmpInst::ICMP_EQ,
FCmpInst::FCMP_OEQ);
break;
case NE_EXPR:
Result = EmitCompare(exp, ICmpInst::ICMP_NE, ICmpInst::ICMP_NE,
FCmpInst::FCMP_UNE);
break;
case UNORDERED_EXPR:
Result = EmitCompare(exp, 0, 0, FCmpInst::FCMP_UNO);
break;
case ORDERED_EXPR:
Result = EmitCompare(exp, 0, 0, FCmpInst::FCMP_ORD);
break;
case UNLT_EXPR: Result = EmitCompare(exp, 0, 0, FCmpInst::FCMP_ULT); break;
case UNLE_EXPR: Result = EmitCompare(exp, 0, 0, FCmpInst::FCMP_ULE); break;
case UNGT_EXPR: Result = EmitCompare(exp, 0, 0, FCmpInst::FCMP_UGT); break;
case UNGE_EXPR: Result = EmitCompare(exp, 0, 0, FCmpInst::FCMP_UGE); break;
case UNEQ_EXPR: Result = EmitCompare(exp, 0, 0, FCmpInst::FCMP_UEQ); break;
case LTGT_EXPR: Result = EmitCompare(exp, 0, 0, FCmpInst::FCMP_ONE); break;
case PLUS_EXPR: Result = EmitBinOp(exp, DestLoc, Instruction::Add);break;
case MINUS_EXPR:Result = EmitBinOp(exp, DestLoc, Instruction::Sub);break;
case MULT_EXPR: Result = EmitBinOp(exp, DestLoc, Instruction::Mul);break;
case EXACT_DIV_EXPR: Result = EmitEXACT_DIV_EXPR(exp, DestLoc); break;
case TRUNC_DIV_EXPR:
if (TYPE_UNSIGNED(TREE_TYPE(exp)))
Result = EmitBinOp(exp, DestLoc, Instruction::UDiv);
else
Result = EmitBinOp(exp, DestLoc, Instruction::SDiv);
break;
case RDIV_EXPR: Result = EmitBinOp(exp, DestLoc, Instruction::FDiv); break;
case CEIL_DIV_EXPR: Result = EmitCEIL_DIV_EXPR(exp); break;
case ROUND_DIV_EXPR: Result = EmitROUND_DIV_EXPR(exp); break;
case TRUNC_MOD_EXPR:
if (TYPE_UNSIGNED(TREE_TYPE(exp)))
Result = EmitBinOp(exp, DestLoc, Instruction::URem);
else
Result = EmitBinOp(exp, DestLoc, Instruction::SRem);
break;
case FLOOR_MOD_EXPR: Result = EmitFLOOR_MOD_EXPR(exp, DestLoc); break;
case BIT_AND_EXPR: Result = EmitBinOp(exp, DestLoc, Instruction::And);break;
case BIT_IOR_EXPR: Result = EmitBinOp(exp, DestLoc, Instruction::Or );break;
case BIT_XOR_EXPR: Result = EmitBinOp(exp, DestLoc, Instruction::Xor);break;
case TRUTH_AND_EXPR: Result = EmitTruthOp(exp, Instruction::And); break;
case TRUTH_OR_EXPR: Result = EmitTruthOp(exp, Instruction::Or); break;
case TRUTH_XOR_EXPR: Result = EmitTruthOp(exp, Instruction::Xor); break;
case RSHIFT_EXPR:
Result = EmitShiftOp(exp,DestLoc,
TYPE_UNSIGNED(TREE_TYPE(exp)) ? Instruction::LShr : Instruction::AShr);
break;
case LSHIFT_EXPR: Result = EmitShiftOp(exp,DestLoc,Instruction::Shl);break;
case RROTATE_EXPR:
Result = EmitRotateOp(exp, Instruction::LShr, Instruction::Shl);
break;
case LROTATE_EXPR:
Result = EmitRotateOp(exp, Instruction::Shl, Instruction::LShr);
break;
case MIN_EXPR:
Result = EmitMinMaxExpr(exp, ICmpInst::ICMP_ULE, ICmpInst::ICMP_SLE,
FCmpInst::FCMP_OLE);
break;
case MAX_EXPR:
Result = EmitMinMaxExpr(exp, ICmpInst::ICMP_UGE, ICmpInst::ICMP_SGE,
FCmpInst::FCMP_OGE);
break;
case CONSTRUCTOR: Result = EmitCONSTRUCTOR(exp, DestLoc); break;
// Complex Math Expressions.
case COMPLEX_CST: EmitCOMPLEX_CST (exp, DestLoc); break;
case COMPLEX_EXPR: EmitCOMPLEX_EXPR(exp, DestLoc); break;
// Constant Expressions
case INTEGER_CST:
if (!DestLoc)
Result = TreeConstantToLLVM::ConvertINTEGER_CST(exp);
else
EmitINTEGER_CST_Aggregate(exp, DestLoc);
break;
case REAL_CST:
Result = TreeConstantToLLVM::ConvertREAL_CST(exp);
break;
case VECTOR_CST:
Result = TreeConstantToLLVM::ConvertVECTOR_CST(exp);
break;
}
if (TheDebugInfo && EXPR_HAS_LOCATION(exp)) {
// Restore location back down the tree.
TheDebugInfo->setLocationFile(EXPR_FILENAME(exp));
TheDebugInfo->setLocationLine(EXPR_LINENO(exp));
}
assert(((DestLoc && Result == 0) || DestLoc == 0) &&
"Expected a scalar or aggregate but got the wrong thing!");
return Result;
}
/// EmitLV - Convert the specified l-value tree node to LLVM code, returning
/// the address of the result.
LValue TreeToLLVM::EmitLV(tree exp) {
switch (TREE_CODE(exp)) {
default:
std::cerr << "Unhandled lvalue expression!\n";
debug_tree(exp);
abort();
case PARM_DECL:
case VAR_DECL:
case FUNCTION_DECL:
case CONST_DECL:
case RESULT_DECL: return EmitLV_DECL(exp);
case ARRAY_RANGE_REF:
case ARRAY_REF: return EmitLV_ARRAY_REF(exp);
case COMPONENT_REF: return EmitLV_COMPONENT_REF(exp);
case BIT_FIELD_REF: return EmitLV_BIT_FIELD_REF(exp);
case REALPART_EXPR: return EmitLV_XXXXPART_EXPR(exp, 0);
case IMAGPART_EXPR: return EmitLV_XXXXPART_EXPR(exp, 1);
// Constants.
case LABEL_DECL: return TreeConstantToLLVM::EmitLV_LABEL_DECL(exp);
case STRING_CST: return LValue(TreeConstantToLLVM::EmitLV_STRING_CST(exp));
// Type Conversion.
case VIEW_CONVERT_EXPR: return EmitLV_VIEW_CONVERT_EXPR(exp);
// Trivial Cases.
case WITH_SIZE_EXPR:
// The address is the address of the operand.
return EmitLV(TREE_OPERAND(exp, 0));
case INDIRECT_REF:
// The lvalue is just the address.
return Emit(TREE_OPERAND(exp, 0), 0);
}
}
//===----------------------------------------------------------------------===//
// ... Utility Functions ...
//===----------------------------------------------------------------------===//
void TreeToLLVM::TODO(tree exp) {
std::cerr << "Unhandled tree node\n";
if (exp) debug_tree(exp);
abort();
}
/// CastToType - Cast the specified value to the specified type if it is
/// not already that type.
Value *TreeToLLVM::CastToType(unsigned opcode, Value *V, const Type* Ty) {
// Eliminate useless casts of a type to itself.
if (V->getType() == Ty)
return V;
// If this is a simple constant operand, fold it now. If it is a constant
// expr operand, fold it below.
if (Constant *C = dyn_cast<Constant>(V))
if (!isa<ConstantExpr>(C))
return ConstantExpr::getCast(Instruction::CastOps(opcode), C, Ty);
// Handle 'trunc (zext i1 X to T2) to i1' as X, because this occurs all over
// the place.
if (ZExtInst *CI = dyn_cast<ZExtInst>(V))
if (Ty == Type::Int1Ty && CI->getOperand(0)->getType() == Type::Int1Ty)
return CI->getOperand(0);
Value *Result = Builder.CreateCast(Instruction::CastOps(opcode), V, Ty,
V->getNameStart());
// If this is a constantexpr, fold the instruction with
// ConstantFoldInstruction to allow TargetData-driven folding to occur.
if (isa<ConstantExpr>(V))
Result = ConstantFoldInstruction(cast<Instruction>(Result), &TD);
return Result;
}
/// CastToAnyType - Cast the specified value to the specified type making no
/// assumptions about the types of the arguments. This creates an inferred cast.
Value *TreeToLLVM::CastToAnyType(Value *V, bool VisSigned,
const Type* Ty, bool TyIsSigned) {
// Eliminate useless casts of a type to itself.
if (V->getType() == Ty)
return V;
// The types are different so we must cast. Use getCastOpcode to create an
// inferred cast opcode.
Instruction::CastOps opc =
CastInst::getCastOpcode(V, VisSigned, Ty, TyIsSigned);
// Generate the cast and return it.
return CastToType(opc, V, Ty);
}
/// CastToUIntType - Cast the specified value to the specified type assuming
/// that the value and type are unsigned integer types.
Value *TreeToLLVM::CastToUIntType(Value *V, const Type* Ty) {
// Eliminate useless casts of a type to itself.
if (V->getType() == Ty)
return V;
unsigned SrcBits = V->getType()->getPrimitiveSizeInBits();
unsigned DstBits = Ty->getPrimitiveSizeInBits();
assert(SrcBits != DstBits && "Types are different but have same #bits?");
Instruction::CastOps opcode =
(SrcBits > DstBits ? Instruction::Trunc : Instruction::ZExt);
return CastToType(opcode, V, Ty);
}
/// CastToSIntType - Cast the specified value to the specified type assuming
/// that the value and type are signed integer types.
Value *TreeToLLVM::CastToSIntType(Value *V, const Type* Ty) {
// Eliminate useless casts of a type to itself.
if (V->getType() == Ty)
return V;
unsigned SrcBits = V->getType()->getPrimitiveSizeInBits();
unsigned DstBits = Ty->getPrimitiveSizeInBits();
assert(SrcBits != DstBits && "Types are different but have same #bits?");
Instruction::CastOps opcode =
(SrcBits > DstBits ? Instruction::Trunc : Instruction::SExt);
return CastToType(opcode, V, Ty);
}
/// CastToFPType - Cast the specified value to the specified type assuming
/// that the value and type or floating point
Value *TreeToLLVM::CastToFPType(Value *V, const Type* Ty) {
unsigned SrcBits = V->getType()->getPrimitiveSizeInBits();
unsigned DstBits = Ty->getPrimitiveSizeInBits();
if (SrcBits == DstBits)
return V;
Instruction::CastOps opcode = (SrcBits > DstBits ?
Instruction::FPTrunc : Instruction::FPExt);
return CastToType(opcode, V, Ty);
}
/// BitCastToType - Insert a BitCast from V to Ty if needed. This is just a
/// shorthand convenience function for CastToType(Instruction::BitCast,V,Ty).
Value *TreeToLLVM::BitCastToType(Value *V, const Type *Ty) {
return CastToType(Instruction::BitCast, V, Ty);
}
/// CreateTemporary - Create a new alloca instruction of the specified type,
/// inserting it into the entry block and returning it. The resulting
/// instruction's type is a pointer to the specified type.
AllocaInst *TreeToLLVM::CreateTemporary(const Type *Ty) {
if (AllocaInsertionPoint == 0) {
// Create a dummy instruction in the entry block as a marker to insert new
// alloc instructions before. It doesn't matter what this instruction is,
// it is dead. This allows us to insert allocas in order without having to
// scan for an insertion point. Use BitCast for int -> int
AllocaInsertionPoint = CastInst::create(Instruction::BitCast,
Constant::getNullValue(Type::Int32Ty), Type::Int32Ty, "alloca point");
// Insert it as the first instruction in the entry block.
Fn->begin()->getInstList().insert(Fn->begin()->begin(),
AllocaInsertionPoint);
}
return new AllocaInst(Ty, 0, "memtmp", AllocaInsertionPoint);
}
/// EmitBlock - Add the specified basic block to the end of the function. If
/// the previous block falls through into it, add an explicit branch. Also,
/// manage fixups for EH info.
void TreeToLLVM::EmitBlock(BasicBlock *BB) {
BasicBlock *CurBB = Builder.GetInsertBlock();
// If the previous block falls through to BB, add an explicit branch.
if (CurBB->getTerminator() == 0) {
// If the previous block has no label and is empty, remove it: it is a
// post-terminator block.
if (CurBB->getName().empty() && CurBB->begin() == CurBB->end()) {
CurBB->eraseFromParent();
if (!CurrentEHScopes.empty()) {
assert(CurrentEHScopes.back().Blocks.back() == CurBB);
CurrentEHScopes.back().Blocks.pop_back();
BlockEHScope.erase(CurBB);
}
} else {
// Otherwise, fall through to this block.
Builder.CreateBr(BB);
}
}
// Add this block.
Fn->getBasicBlockList().push_back(BB);
Builder.SetInsertPoint(BB); // It is now the current block.
// If there are no exception scopes that contain this block, exit. This is
// common for C++ code and almost uniformly true for C code.
if (CurrentEHScopes.empty()) return;
// Otherwise, we now know that this block is in this exception scope. Update
// records.
CurrentEHScopes.back().Blocks.push_back(BB);
BlockEHScope[BB] = CurrentEHScopes.size()-1;
}
/// CopyAggregate - Recursively traverse the potientially aggregate src/dest
/// ptrs, copying all of the elements.
static void CopyAggregate(Value *DestPtr, Value *SrcPtr,
bool isDstVolatile, bool isSrcVolatile,
unsigned Alignment, LLVMBuilder &Builder) {
assert(DestPtr->getType() == SrcPtr->getType() &&
"Cannot copy between two pointers of different type!");
const Type *ElTy = cast<PointerType>(DestPtr->getType())->getElementType();
unsigned TypeAlign = getTargetData().getABITypeAlignment(ElTy);
Alignment = MIN(Alignment, TypeAlign);
if (ElTy->isFirstClassType()) {
LoadInst *V = Builder.CreateLoad(SrcPtr, isSrcVolatile, "tmp");
StoreInst *S = Builder.CreateStore(V, DestPtr, isDstVolatile);
V->setAlignment(Alignment);
S->setAlignment(Alignment);
} else if (const StructType *STy = dyn_cast<StructType>(ElTy)) {
Constant *Zero = ConstantInt::get(Type::Int32Ty, 0);
for (unsigned i = 0, e = STy->getNumElements(); i != e; ++i) {
if (isPaddingElement(STy, i))
continue;
Constant *Idx = ConstantInt::get(Type::Int32Ty, i);
Value *Idxs[2] = { Zero, Idx };
Value *DElPtr = Builder.CreateGEP(DestPtr, Idxs, Idxs + 2, "tmp");
Value *SElPtr = Builder.CreateGEP(SrcPtr, Idxs, Idxs + 2, "tmp");
CopyAggregate(DElPtr, SElPtr, isDstVolatile, isSrcVolatile, Alignment,
Builder);
}
} else {
const ArrayType *ATy = cast<ArrayType>(ElTy);
Constant *Zero = ConstantInt::get(Type::Int32Ty, 0);
for (unsigned i = 0, e = ATy->getNumElements(); i != e; ++i) {
Constant *Idx = ConstantInt::get(Type::Int32Ty, i);
Value *Idxs[2] = { Zero, Idx };
Value *DElPtr = Builder.CreateGEP(DestPtr, Idxs, Idxs + 2, "tmp");
Value *SElPtr = Builder.CreateGEP(SrcPtr, Idxs, Idxs + 2, "tmp");
CopyAggregate(DElPtr, SElPtr, isDstVolatile, isSrcVolatile, Alignment,
Builder);
}
}
}
/// CountAggregateElements - Return the number of elements in the specified type
/// that will need to be loaded/stored if we copy this by explicit accesses.
static unsigned CountAggregateElements(const Type *Ty) {
if (Ty->isFirstClassType()) return 1;
if (const StructType *STy = dyn_cast<StructType>(Ty)) {
unsigned NumElts = 0;
for (unsigned i = 0, e = STy->getNumElements(); i != e; ++i)
NumElts += CountAggregateElements(STy->getElementType(i));
return NumElts;
} else {
const ArrayType *ATy = cast<ArrayType>(Ty);
return ATy->getNumElements()*CountAggregateElements(ATy->getElementType());
}
}
#ifndef TARGET_LLVM_MIN_BYTES_COPY_BY_MEMCPY
#define TARGET_LLVM_MIN_BYTES_COPY_BY_MEMCPY 64
#endif
/// EmitAggregateCopy - Copy the elements from SrcPtr to DestPtr, using the
/// GCC type specified by GCCType to know which elements to copy.
void TreeToLLVM::EmitAggregateCopy(Value *DestPtr, Value *SrcPtr, tree type,
bool isDstVolatile, bool isSrcVolatile,
unsigned Alignment) {
if (DestPtr == SrcPtr && !isDstVolatile && !isSrcVolatile)
return; // noop copy.
// If the type is small, copy the elements instead of using a block copy.
if (TREE_CODE(TYPE_SIZE(type)) == INTEGER_CST &&
TREE_INT_CST_LOW(TYPE_SIZE_UNIT(type)) <
TARGET_LLVM_MIN_BYTES_COPY_BY_MEMCPY) {
const Type *LLVMTy = ConvertType(type);
// If the GCC type is not fully covered by the LLVM type, use memcpy. This
// can occur with unions etc.
if (!TheTypeConverter->GCCTypeOverlapsWithLLVMTypePadding(type, LLVMTy) &&
// Don't copy tons of tiny elements.
CountAggregateElements(LLVMTy) <= 8) {
DestPtr = CastToType(Instruction::BitCast, DestPtr,
PointerType::get(LLVMTy));
SrcPtr = CastToType(Instruction::BitCast, SrcPtr,
PointerType::get(LLVMTy));
CopyAggregate(DestPtr, SrcPtr, isDstVolatile, isSrcVolatile, Alignment,
Builder);
return;
}
}
Value *TypeSize = Emit(TYPE_SIZE_UNIT(type), 0);
EmitMemCpy(DestPtr, SrcPtr, TypeSize, Alignment);
}
/// ZeroAggregate - Recursively traverse the potientially aggregate dest
/// ptr, zero'ing all of the elements.
static void ZeroAggregate(Value *DestPtr, LLVMBuilder &Builder) {
const Type *ElTy = cast<PointerType>(DestPtr->getType())->getElementType();
if (ElTy->isFirstClassType()) {
Builder.CreateStore(Constant::getNullValue(ElTy), DestPtr);
} else if (const StructType *STy = dyn_cast<StructType>(ElTy)) {
Constant *Zero = ConstantInt::get(Type::Int32Ty, 0);
for (unsigned i = 0, e = STy->getNumElements(); i != e; ++i) {
Constant *Idx = ConstantInt::get(Type::Int32Ty, i);
Value *Idxs[2] = { Zero, Idx };
ZeroAggregate(Builder.CreateGEP(DestPtr, Idxs, Idxs + 2, "tmp"),
Builder);
}
} else {
const ArrayType *ATy = cast<ArrayType>(ElTy);
Constant *Zero = ConstantInt::get(Type::Int32Ty, 0);
for (unsigned i = 0, e = ATy->getNumElements(); i != e; ++i) {
Constant *Idx = ConstantInt::get(Type::Int32Ty, i);
Value *Idxs[2] = { Zero, Idx };
ZeroAggregate(Builder.CreateGEP(DestPtr, Idxs, Idxs + 2, "tmp"),
Builder);
}
}
}
/// EmitAggregateZero - Zero the elements of DestPtr.
///
void TreeToLLVM::EmitAggregateZero(Value *DestPtr, tree type) {
// If the type is small, copy the elements instead of using a block copy.
if (TREE_CODE(TYPE_SIZE(type)) == INTEGER_CST &&
TREE_INT_CST_LOW(TYPE_SIZE_UNIT(type)) < 128) {
const Type *LLVMTy = ConvertType(type);
DestPtr = CastToType(Instruction::BitCast, DestPtr,
PointerType::get(LLVMTy));
// FIXME: Is this always safe? The LLVM type might theoretically have holes
// or might be suboptimal to copy this way. It may be better to copy the
// structure by the GCCType's fields.
ZeroAggregate(DestPtr, Builder);
return;
}
unsigned Alignment = TYPE_ALIGN_OK(type) ? (TYPE_ALIGN_UNIT(type) & ~0U) : 0;
EmitMemSet(DestPtr, ConstantInt::get(Type::Int8Ty, 0),
Emit(TYPE_SIZE_UNIT(type), 0), Alignment);
}
void TreeToLLVM::EmitMemCpy(Value *DestPtr, Value *SrcPtr, Value *Size,
unsigned Align) {
const Type *SBP = PointerType::get(Type::Int8Ty);
const Type *IntPtr = TD.getIntPtrType();
Value *Ops[4] = {
CastToType(Instruction::BitCast, DestPtr, SBP),
CastToType(Instruction::BitCast, SrcPtr, SBP),
CastToSIntType(Size, IntPtr),
ConstantInt::get(Type::Int32Ty, Align)
};
Intrinsic::ID IID =
(IntPtr == Type::Int32Ty) ? Intrinsic::memcpy_i32 : Intrinsic::memcpy_i64;
Builder.CreateCall(Intrinsic::getDeclaration(TheModule, IID), Ops, Ops+4);
}
void TreeToLLVM::EmitMemMove(Value *DestPtr, Value *SrcPtr, Value *Size,
unsigned Align) {
const Type *SBP = PointerType::get(Type::Int8Ty);
const Type *IntPtr = TD.getIntPtrType();
Value *Ops[4] = {
CastToType(Instruction::BitCast, DestPtr, SBP),
CastToType(Instruction::BitCast, SrcPtr, SBP),
CastToSIntType(Size, IntPtr),
ConstantInt::get(Type::Int32Ty, Align)
};
Intrinsic::ID IID =
(IntPtr == Type::Int32Ty) ? Intrinsic::memmove_i32 : Intrinsic::memmove_i64;
Builder.CreateCall(Intrinsic::getDeclaration(TheModule, IID), Ops, Ops+4);
}
void TreeToLLVM::EmitMemSet(Value *DestPtr, Value *SrcVal, Value *Size,
unsigned Align) {
const Type *SBP = PointerType::get(Type::Int8Ty);
const Type *IntPtr = TD.getIntPtrType();
Value *Ops[4] = {
CastToType(Instruction::BitCast, DestPtr, SBP),
CastToSIntType(SrcVal, Type::Int8Ty),
CastToSIntType(Size, IntPtr),
ConstantInt::get(Type::Int32Ty, Align)
};
Intrinsic::ID IID =
(IntPtr == Type::Int32Ty) ? Intrinsic::memset_i32 : Intrinsic::memset_i64;
Builder.CreateCall(Intrinsic::getDeclaration(TheModule, IID), Ops, Ops+4);
}
/// EmitBranchInternal - Emit an unconditional branch to the specified basic
/// block, running cleanups if the branch exits scopes. The arguments specify
/// how to handle these cleanups.
///
/// This function is used for a variety of control flow purposes. In particular,
/// it is responsible for determining which cleanups must be executed as a
/// result of leaving blocks with destructors. For branches that require
/// cleanups, it schedules cleanup insertion with a goto_fixup record. When the
/// block containing the cleanup is exited, the end-of-block code inserts the
/// cleanups as indicated by goto_fixups.
///
/// Note that some cleanups only apply to exception edges. If this is an
/// exception edge (as indicated by IsExceptionEdge) these are expanded,
/// otherwise not.
///
/// Note that all calling code should emit a new basic block after this, so that
/// future code does not fall after the terminator.
///
void TreeToLLVM::EmitBranchInternal(BasicBlock *Dest, bool IsExceptionEdge) {
// Insert the branch.
BranchInst *BI = Builder.CreateBr(Dest);
// If there are no current exception scopes, this edge *couldn't* need
// cleanups. It is not possible to jump into a scope that requires a cleanup.
// This keeps the C case fast.
if (CurrentEHScopes.empty()) return;
// If the destination block has already been emitted, this is a backwards
// branch, and we can resolve it now.
if (Dest->getParent()) {
// This is a forward reference to a block. Since we know that we can't jump
// INTO a region that has cleanups, we can only be branching out.
std::map<BasicBlock*, unsigned>::iterator I = BlockEHScope.find(Dest);
if (I != BlockEHScope.end() && I->second == CurrentEHScopes.size() - 1)
return; // Branch within the same EH scope.
assert((I == BlockEHScope.end() || I->second < CurrentEHScopes.size()) &&
"Invalid branch into EH region");
}
AddBranchFixup(BI, IsExceptionEdge);
}
/// AddBranchFixup - Add the specified unconditional branch to the fixup list
/// for the outermost exception scope, merging it if there is already a fixup
/// that works.
void TreeToLLVM::AddBranchFixup(BranchInst *BI, bool isExceptionEdge) {
BasicBlock *Dest = BI->getSuccessor(0);
// Check to see if we already have a fixup for this destination.
std::vector<BranchFixup> &BranchFixups = CurrentEHScopes.back().BranchFixups;
for (unsigned i = 0, e = BranchFixups.size(); i != e; ++i)
if (BranchFixups[i].SrcBranch->getSuccessor(0) == Dest &&
BranchFixups[i].isExceptionEdge == isExceptionEdge) {
BranchFixup &Fixup = BranchFixups[i];
// We found a fixup for this destination already. Recycle it.
if (&Fixup.SrcBranch->getParent()->front() == Fixup.SrcBranch) {
// If the fixup's branch is the only instruction in its block, change
// the branch we just emitted to branch to that block instead.
BI->setSuccessor(0, Fixup.SrcBranch->getParent());
return;
}
if (&Builder.GetInsertBlock()->front() == BI) {
// Otherwise, if this block is empty except for the branch, change the
// fixup to jump here and change the fixup to fix this branch.
Fixup.SrcBranch->setSuccessor(0, Builder.GetInsertBlock());
Fixup.SrcBranch = BI;
return;
}
// Finally, if neither block is empty, create a new (empty) one and
// revector BOTH branches to the new block.
EmitBlock(new BasicBlock("cleanup"));
BranchInst *NewBI = Builder.CreateBr(Dest);
BI->setSuccessor(0, Builder.GetInsertBlock());
Fixup.SrcBranch->setSuccessor(0, Builder.GetInsertBlock());
Fixup.SrcBranch = NewBI;
return;
}
// Otherwise, create a new fixup for this branch so we know that it needs
// cleanups when we finish up the scopes that it is in.
BranchFixups.push_back(BranchFixup(BI, isExceptionEdge));
}
// Emits annotate intrinsic if the decl has the annotate attribute set.
void TreeToLLVM::EmitAnnotateIntrinsic(Value *V, tree decl) {
// Handle annotate attribute on global.
tree annotateAttr = lookup_attribute("annotate", DECL_ATTRIBUTES (decl));
if (!annotateAttr)
return;
Function *annotateFun = Intrinsic::getDeclaration(TheModule,
Intrinsic::var_annotation);
// Get file and line number
Constant *lineNo = ConstantInt::get(Type::Int32Ty, DECL_SOURCE_LINE(decl));
Constant *file = ConvertMetadataStringToGV(DECL_SOURCE_FILE(decl));
const Type *SBP= PointerType::get(Type::Int8Ty);
file = ConstantExpr::getBitCast(file, SBP);
// There may be multiple annotate attributes. Pass return of lookup_attr
// to successive lookups.
while (annotateAttr) {
// Each annotate attribute is a tree list.
// Get value of list which is our linked list of args.
tree args = TREE_VALUE(annotateAttr);
// Each annotate attribute may have multiple args.
// Treat each arg as if it were a separate annotate attribute.
for (tree a = args; a; a = TREE_CHAIN(a)) {
// Each element of the arg list is a tree list, so get value
tree val = TREE_VALUE(a);
// Assert its a string, and then get that string.
assert(TREE_CODE(val) == STRING_CST &&
"Annotate attribute arg should always be a string");
const Type *SBP = PointerType::get(Type::Int8Ty);
Constant *strGV = TreeConstantToLLVM::EmitLV_STRING_CST(val);
Value *Ops[4] = {
BitCastToType(V, SBP),
BitCastToType(strGV, SBP),
file,
lineNo
};
Builder.CreateCall(annotateFun, Ops, Ops+4);
}
// Get next annotate attribute.
annotateAttr = TREE_CHAIN(annotateAttr);
if (annotateAttr)
annotateAttr = lookup_attribute("annotate", annotateAttr);
}
}
//===----------------------------------------------------------------------===//
// ... Basic Lists and Binding Scopes ...
//===----------------------------------------------------------------------===//
/// EmitAutomaticVariableDecl - Emit the function-local decl to the current
/// function and set DECL_LLVM for the decl to the right pointer.
void TreeToLLVM::EmitAutomaticVariableDecl(tree decl) {
tree type = TREE_TYPE(decl);
// An LLVM value pointer for this decl may already be set, for example, if the
// named return value optimization is being applied to this function, and
// this variable is the one being returned.
assert(!DECL_LLVM_SET_P(decl) && "Shouldn't call this on an emitted var!");
// For a CONST_DECL, set mode, alignment, and sizes from those of the
// type in case this node is used in a reference.
if (TREE_CODE(decl) == CONST_DECL) {
DECL_MODE(decl) = TYPE_MODE(type);
DECL_ALIGN(decl) = TYPE_ALIGN(type);
DECL_SIZE(decl) = TYPE_SIZE(type);
DECL_SIZE_UNIT(decl) = TYPE_SIZE_UNIT(type);
return;
}
// Otherwise, only automatic (and result) variables need any expansion done.
// Static and external variables, and external functions, will be handled by
// `assemble_variable' (called from finish_decl). TYPE_DECL requires nothing.
// PARM_DECLs are handled in `llvm_expand_function_start'.
if ((TREE_CODE(decl) != VAR_DECL && TREE_CODE(decl) != RESULT_DECL) ||
TREE_STATIC(decl) || DECL_EXTERNAL(decl) || type == error_mark_node)
return;
// SSA temporaries are handled specially: their DECL_LLVM is set when the
// definition is encountered.
if (isGCC_SSA_Temporary(decl))
return;
// If this is just the rotten husk of a variable that the gimplifier
// eliminated all uses of, but is preserving for debug info, ignore it.
if (TREE_CODE(decl) == VAR_DECL && DECL_VALUE_EXPR(decl))
return;
const Type *Ty; // Type to allocate
Value *Size = 0; // Amount to alloca (null for 1)
unsigned Alignment = 0; // Alignment in bytes.
if (DECL_SIZE(decl) == 0) { // Variable with incomplete type.
if (DECL_INITIAL(decl) == 0)
return; // Error message was already done; now avoid a crash.
else {
// "An initializer is going to decide the size of this array."??
TODO(decl);
abort();
}
} else if (TREE_CODE(DECL_SIZE_UNIT(decl)) == INTEGER_CST) {
// Variable of fixed size that goes on the stack.
Ty = ConvertType(type);
// Set alignment we actually gave this decl.
if (DECL_MODE(decl) == BLKmode)
DECL_ALIGN(decl) = BIGGEST_ALIGNMENT;
else
DECL_ALIGN(decl) = GET_MODE_BITSIZE(DECL_MODE(decl));
DECL_USER_ALIGN(decl) = 0;
Alignment = DECL_ALIGN(decl)/8;
} else {
tree length;
// Dynamic-size object: must push space on the stack.
if (TREE_CODE(type) == ARRAY_TYPE &&
isSequentialCompatible(type) &&
(length = arrayLength(type))) {
Ty = ConvertType(TREE_TYPE(type)); // Get array element type.
// Compute the number of elements in the array.
Size = Emit(length, 0);
} else {
// Compute the variable's size in bytes.
Size = Emit(DECL_SIZE_UNIT(decl), 0);
Ty = Type::Int8Ty;
}
Size = CastToUIntType(Size, Type::Int32Ty);
}
const char *Name; // Name of variable
if (DECL_NAME(decl))
Name = IDENTIFIER_POINTER(DECL_NAME(decl));
else if (TREE_CODE(decl) == RESULT_DECL)
Name = "retval";
else
Name = "tmp";
// Insert an alloca for this variable.
AllocaInst *AI;
if (!Size) { // Fixed size alloca -> entry block.
AI = CreateTemporary(Ty);
AI->setName(Name);
} else {
AI = Builder.CreateAlloca(Ty, Size, Name);
}
AI->setAlignment(Alignment);
SET_DECL_LLVM(decl, AI);
// Handle annotate attributes
if (DECL_ATTRIBUTES(decl))
EmitAnnotateIntrinsic(AI, decl);
if (TheDebugInfo) {
if (DECL_NAME(decl)) {
TheDebugInfo->EmitDeclare(decl, llvm::dwarf::DW_TAG_auto_variable,
Name, TREE_TYPE(decl), AI,
Builder.GetInsertBlock());
} else if (TREE_CODE(decl) == RESULT_DECL) {
TheDebugInfo->EmitDeclare(decl, llvm::dwarf::DW_TAG_return_variable,
Name, TREE_TYPE(decl), AI,
Builder.GetInsertBlock());
}
}
}
Value *TreeToLLVM::EmitBIND_EXPR(tree exp, Value *DestLoc) {
// Start region only if not top level.
if (TheDebugInfo && DECL_SAVED_TREE(FnDecl) != exp)
TheDebugInfo->EmitRegionStart(Fn, Builder.GetInsertBlock());
// Mark the corresponding BLOCK for output in its proper place.
if (BIND_EXPR_BLOCK(exp) != 0 && !TREE_USED(BIND_EXPR_BLOCK(exp)))
TREE_USED(BIND_EXPR_BLOCK(exp)) = 1;
//lang_hooks.decls.insert_block(BIND_EXPR_BLOCK(exp));
// If VARS have not yet been expanded, expand them now.
tree Var = BIND_EXPR_VARS(exp);
for (; Var; Var = TREE_CHAIN(Var)) {
if (TREE_STATIC(Var)) {
// If this is an inlined copy of a static local variable, look up the
// original.
tree RealVar = DECL_ORIGIN(Var);
// If we haven't already emitted the var, do so now.
if (!TREE_ASM_WRITTEN(RealVar) && !lang_hooks.expand_decl(RealVar) &&
TREE_CODE (Var) == VAR_DECL)
rest_of_decl_compilation(RealVar, 0, 0);
continue;
}
// Otherwise, if this is an automatic variable that hasn't been emitted, do
// so now.
if (!DECL_LLVM_SET_P(Var))
EmitAutomaticVariableDecl(Var);
}
// Finally, emit the body of the bind expression.
Value *Result = Emit(BIND_EXPR_BODY(exp), DestLoc);
TREE_USED(exp) = 1;
// End region only if not top level.
if (TheDebugInfo && DECL_SAVED_TREE(FnDecl) != exp)
TheDebugInfo->EmitRegionEnd(Fn, Builder.GetInsertBlock());
return Result;
}
Value *TreeToLLVM::EmitSTATEMENT_LIST(tree exp, Value *DestLoc) {
assert(DestLoc == 0 && "Does not return a value!");
// Convert each statement.
for (tree_stmt_iterator I = tsi_start(exp); !tsi_end_p(I); tsi_next(&I)) {
tree stmt = tsi_stmt(I);
Value *DestLoc = 0;
// If this stmt returns an aggregate value (e.g. a call whose result is
// ignored), create a temporary to receive the value. Note that we don't
// do this for MODIFY_EXPRs as an efficiency hack.
if (isAggregateTreeType(TREE_TYPE(stmt)) && TREE_CODE(stmt) != MODIFY_EXPR)
DestLoc = CreateTemporary(ConvertType(TREE_TYPE(stmt)));
Emit(stmt, DestLoc);
}
return 0;
}
//===----------------------------------------------------------------------===//
// ... Address Of Labels Extension Support ...
//===----------------------------------------------------------------------===//
/// getIndirectGotoBlockNumber - Return the unique ID of the specified basic
/// block for uses that take the address of it.
Constant *TreeToLLVM::getIndirectGotoBlockNumber(BasicBlock *BB) {
ConstantInt *&Val = AddressTakenBBNumbers[BB];
if (Val) return Val;
// Assign the new ID, update AddressTakenBBNumbers to remember it.
uint64_t BlockNo = ++NumAddressTakenBlocks;
BlockNo &= ~0ULL >> (64-TD.getPointerSizeInBits());
Val = ConstantInt::get(TD.getIntPtrType(), BlockNo);
// Add it to the switch statement in the indirect goto block.
cast<SwitchInst>(getIndirectGotoBlock()->getTerminator())->addCase(Val, BB);
return Val;
}
/// getIndirectGotoBlock - Get (and potentially lazily create) the indirect
/// goto block.
BasicBlock *TreeToLLVM::getIndirectGotoBlock() {
if (IndirectGotoBlock) return IndirectGotoBlock;
// Create a temporary for the value to be switched on.
IndirectGotoValue = CreateTemporary(TD.getIntPtrType());
// Create the block, emit a load, and emit the switch in the block.
IndirectGotoBlock = new BasicBlock("indirectgoto");
Value *Ld = new LoadInst(IndirectGotoValue, "gotodest", IndirectGotoBlock);
new SwitchInst(Ld, IndirectGotoBlock, 0, IndirectGotoBlock);
// Finally, return it.
return IndirectGotoBlock;
}
//===----------------------------------------------------------------------===//
// ... Control Flow ...
//===----------------------------------------------------------------------===//
/// getLabelDeclBlock - Lazily get and create a basic block for the specified
/// label.
static BasicBlock *getLabelDeclBlock(tree LabelDecl) {
assert(TREE_CODE(LabelDecl) == LABEL_DECL && "Isn't a label!?");
if (DECL_LLVM_SET_P(LabelDecl))
return cast<BasicBlock>(DECL_LLVM(LabelDecl));
const char *Name = "bb";
if (DECL_NAME(LabelDecl))
Name = IDENTIFIER_POINTER(DECL_NAME(LabelDecl));
BasicBlock *NewBB = new BasicBlock(Name);
SET_DECL_LLVM(LabelDecl, NewBB);
return NewBB;
}
/// EmitLABEL_EXPR - Emit the basic block corresponding to the specified label.
///
Value *TreeToLLVM::EmitLABEL_EXPR(tree exp) {
EmitBlock(getLabelDeclBlock(TREE_OPERAND(exp, 0)));
return 0;
}
Value *TreeToLLVM::EmitGOTO_EXPR(tree exp) {
if (TREE_CODE(TREE_OPERAND(exp, 0)) == LABEL_DECL) {
// Direct branch.
EmitBranchInternal(getLabelDeclBlock(TREE_OPERAND(exp, 0)), false);
} else {
// Otherwise we have an indirect goto.
BasicBlock *DestBB = getIndirectGotoBlock();
// Store the destination block to the GotoValue alloca.
Value *V = Emit(TREE_OPERAND(exp, 0), 0);
V = CastToType(Instruction::PtrToInt, V, TD.getIntPtrType());
Builder.CreateStore(V, IndirectGotoValue);
// NOTE: This is HORRIBLY INCORRECT in the presence of exception handlers.
// There should be one collector block per cleanup level! Note that
// standard GCC gets this wrong as well.
//
EmitBranchInternal(DestBB, false);
}
EmitBlock(new BasicBlock(""));
return 0;
}
Value *TreeToLLVM::EmitRETURN_EXPR(tree exp, Value *DestLoc) {
assert(DestLoc == 0 && "Does not return a value!");
if (TREE_OPERAND(exp, 0)) {
// Emit the expression, including the assignment to RESULT_DECL. If the
// operand is an aggregate value, create a temporary to evaluate it into.
Value *DestLoc = 0;
const Type *DestTy = ConvertType(TREE_TYPE(TREE_OPERAND(exp, 0)));
if (!DestTy->isFirstClassType() && TREE_CODE(exp) != MODIFY_EXPR)
DestLoc = CreateTemporary(DestTy);
Emit(TREE_OPERAND(exp, 0), DestLoc);
}
// Emit a branch to the exit label.
EmitBranchInternal(ReturnBB, false);
EmitBlock(new BasicBlock(""));
return 0;
}
Value *TreeToLLVM::EmitCOND_EXPR(tree exp) {
// Emit the conditional expression.
Value *Cond = Emit(COND_EXPR_COND(exp), 0);
// If its not already a bool, insert a comparison against zero to make it so.
if (Cond->getType() != Type::Int1Ty)
Cond = Builder.CreateICmpNE(Cond, Constant::getNullValue(Cond->getType()),
"toBool");
tree Then = COND_EXPR_THEN(exp);
tree Else = COND_EXPR_ELSE(exp);
// One extremely common pattern produced by the loop lowering code are
// COND_EXPRS that look like:
//
// if (cond) { goto <D905>; } else { goto <D907>; }
//
// The generic code handles this below, but there is no reason to create a
// cond branch to two blocks which just contain branches themselves.
// Note that we only do this if we're not in the presence of C++ exceptions.
// C++ exceptions could require information for the edge, which requires the
// uncond branch to be available.
if (CurrentEHScopes.empty() && TREE_CODE(Then) == STATEMENT_LIST &&
TREE_CODE(Else) == STATEMENT_LIST) {
tree_stmt_iterator ThenI = tsi_start(Then), ElseI = tsi_start(Else);
if (!tsi_end_p(ThenI) && !tsi_end_p(ElseI)) { // {} isn't empty.
tree ThenStmt = tsi_stmt(ThenI), ElseStmt = tsi_stmt(ElseI);
tsi_next(&ThenI);
tsi_next(&ElseI);
if (TREE_CODE(ThenStmt) == GOTO_EXPR && // Found two uncond gotos.
TREE_CODE(ElseStmt) == GOTO_EXPR &&
tsi_end_p(ThenI) && tsi_end_p(ElseI) && // Nothing after them.
TREE_CODE(TREE_OPERAND(ThenStmt, 0)) == LABEL_DECL &&// Not goto *p.
TREE_CODE(TREE_OPERAND(ElseStmt, 0)) == LABEL_DECL) {
BasicBlock *ThenDest = getLabelDeclBlock(TREE_OPERAND(ThenStmt, 0));
BasicBlock *ElseDest = getLabelDeclBlock(TREE_OPERAND(ElseStmt, 0));
// Okay, we have success. Output the conditional branch.
Builder.CreateCondBr(Cond, ThenDest, ElseDest);
// Emit a "fallthrough" block, which is almost certainly dead.
EmitBlock(new BasicBlock(""));
return 0;
}
}
}
BasicBlock *TrueBlock = new BasicBlock("cond_true");
BasicBlock *FalseBlock;
BasicBlock *ContBlock = new BasicBlock("cond_next");
// Another extremely common case we want to handle are if/then blocks with
// no else. The gimplifier turns these into:
//
// if (cond) { goto <D905>; } else { }
//
// Recognize when the else is an empty STATEMENT_LIST, and don't emit the
// else if so.
//
bool HasEmptyElse =
TREE_CODE(Else) == STATEMENT_LIST && tsi_end_p(tsi_start(Else));
if (HasEmptyElse)
FalseBlock = ContBlock;
else
FalseBlock = new BasicBlock("cond_false");
// Emit the branch based on the condition.
Builder.CreateCondBr(Cond, TrueBlock, FalseBlock);
// Emit the true code.
EmitBlock(TrueBlock);
Emit(Then, 0);
// If this is an if/then/else cond-expr, emit the else part, otherwise, just
// fall through to the ContBlock.
if (!HasEmptyElse) {
if (Builder.GetInsertBlock()->getTerminator() == 0 &&
(!Builder.GetInsertBlock()->getName().empty() ||
!Builder.GetInsertBlock()->use_empty()))
Builder.CreateBr(ContBlock); // Branch to continue block.
EmitBlock(FalseBlock);
Emit(Else, 0);
}
EmitBlock(ContBlock);
return 0;
}
Value *TreeToLLVM::EmitSWITCH_EXPR(tree exp) {
tree Cases = SWITCH_LABELS(exp);
// Emit the condition.
Value *SwitchExp = Emit(SWITCH_COND(exp), 0);
bool ExpIsSigned = !TYPE_UNSIGNED(TREE_TYPE(SWITCH_COND(exp)));
// Emit the switch instruction.
SwitchInst *SI = Builder.CreateSwitch(SwitchExp, Builder.GetInsertBlock(),
TREE_VEC_LENGTH(Cases));
EmitBlock(new BasicBlock(""));
// Default location starts out as fall-through
SI->setSuccessor(0, Builder.GetInsertBlock());
assert(!SWITCH_BODY(exp) && "not a gimple switch?");
BasicBlock *DefaultDest = NULL;
for (unsigned i = 0, e = TREE_VEC_LENGTH(Cases); i != e; ++i) {
BasicBlock *Dest = getLabelDeclBlock(CASE_LABEL(TREE_VEC_ELT(Cases, i)));
tree low = CASE_LOW(TREE_VEC_ELT(Cases, i));
if (!low) {
DefaultDest = Dest;
continue;
}
// Convert the integer to the right type.
Value *Val = Emit(low, 0);
Val = CastToAnyType(Val, !TYPE_UNSIGNED(TREE_TYPE(low)),
SwitchExp->getType(), ExpIsSigned);
ConstantInt *LowC = cast<ConstantInt>(Val);
tree high = CASE_HIGH(TREE_VEC_ELT(Cases, i));
if (!high) {
SI->addCase(LowC, Dest); // Single destination.
continue;
}
// Otherwise, we have a range, like 'case 1 ... 17'.
Val = Emit(high, 0);
// Make sure the case value is the same type as the switch expression
Val = CastToAnyType(Val, !TYPE_UNSIGNED(TREE_TYPE(high)),
SwitchExp->getType(), ExpIsSigned);
ConstantInt *HighC = cast<ConstantInt>(Val);
APInt Range = HighC->getValue() - LowC->getValue();
if (Range.ult(APInt(Range.getBitWidth(), 64))) {
// Add all of the necessary successors to the switch.
APInt CurrentValue = LowC->getValue();
while (1) {
SI->addCase(LowC, Dest);
if (LowC == HighC) break; // Emitted the last one.
CurrentValue++;
LowC = ConstantInt::get(CurrentValue);
}
} else {
// The range is too big to add to the switch - emit an "if".
Value *Diff = Builder.CreateSub(SwitchExp, LowC, "tmp");
Value *Cond = Builder.CreateICmpULE(Diff, ConstantInt::get(Range), "tmp");
BasicBlock *False_Block = new BasicBlock("case_false");
Builder.CreateCondBr(Cond, Dest, False_Block);
EmitBlock(False_Block);
}
}
if (DefaultDest)
if (SI->getSuccessor(0) == Builder.GetInsertBlock())
SI->setSuccessor(0, DefaultDest);
else {
Builder.CreateBr(DefaultDest);
// Emit a "fallthrough" block, which is almost certainly dead.
EmitBlock(new BasicBlock(""));
}
return 0;
}
#ifndef NDEBUG
void TreeToLLVM::dumpEHScopes() const {
std::cerr << CurrentEHScopes.size() << " EH Scopes:\n";
for (unsigned i = 0, e = CurrentEHScopes.size(); i != e; ++i) {
std::cerr << " " << i << ". catch=" << (void*)CurrentEHScopes[i].CatchExpr
<< " #blocks=" << CurrentEHScopes[i].Blocks.size()
<< " #fixups=" << CurrentEHScopes[i].BranchFixups.size() << "\n";
for (unsigned f = 0, e = CurrentEHScopes[i].BranchFixups.size(); f != e;++f)
std::cerr << " Fixup #" << f << ": isEH="
<< CurrentEHScopes[i].BranchFixups[f].isExceptionEdge
<< " br = " << *CurrentEHScopes[i].BranchFixups[f].SrcBranch;
}
}
#endif
/// StripLLVMTranslationFn - Recursive function called from walk_trees to
/// implement StripLLVMTranslation.
static tree StripLLVMTranslationFn(tree *nodep, int *walk_subtrees,
void *data) {
tree node = *nodep;
if (TYPE_P(node)) {
// Don't walk into types.
*walk_subtrees = 0;
} else if (TREE_CODE(node) == STATEMENT_LIST) {
// Look for basic block labels, clearing them out.
for (tree_stmt_iterator I = tsi_start(node); !tsi_end_p(I); tsi_next(&I))
if (TREE_CODE(tsi_stmt(I)) == LABEL_EXPR)
SET_DECL_LLVM(TREE_OPERAND(tsi_stmt(I), 0), 0);
} else if (TREE_CODE(node) == BIND_EXPR) {
// Reset the declarations for local vars.
tree Var = BIND_EXPR_VARS(node);
for (; Var; Var = TREE_CHAIN(Var)) {
if (TREE_CODE(Var) == VAR_DECL && !TREE_STATIC(Var))
SET_DECL_LLVM(Var, 0);
}
}
return NULL_TREE;
}
/// StripLLVMTranslation - Given a block of code, walk it stripping off LLVM
/// information from declarations. This permits the code to be expanded into
/// multiple places in the code without (e.g.) emitting the same LABEL_DECL node
/// into multiple places.
static void StripLLVMTranslation(tree code) {
// Strip off llvm code.
walk_tree_without_duplicates(&code, StripLLVMTranslationFn, 0);
}
/// GatherTypeInfo - Walk through the expression gathering all the
/// typeinfos that are used.
void TreeToLLVM::GatherTypeInfo(tree exp,
std::vector<Constant *> &TypeInfos) {
if (TREE_CODE(exp) == CATCH_EXPR || TREE_CODE(exp) == EH_FILTER_EXPR) {
tree Types = TREE_CODE(exp) == CATCH_EXPR ? CATCH_TYPES(exp)
: EH_FILTER_TYPES(exp);
if (!Types) {
// Catch all or empty filter.
if (TREE_CODE(exp) == CATCH_EXPR)
// Catch all.
TypeInfos.push_back(
Constant::getNullValue(PointerType::get(Type::Int8Ty))
);
} else if (TREE_CODE(Types) != TREE_LIST) {
// Construct typeinfo object. Each call will produce a new expression
// even if duplicate.
tree TypeInfoNopExpr = (*lang_eh_runtime_type)(Types);
// Produce value. Duplicate typeinfo get folded here.
Value *TypeInfo = Emit(TypeInfoNopExpr, 0);
// Capture typeinfo.
TypeInfos.push_back(cast<Constant>(TypeInfo));
} else {
for (; Types; Types = TREE_CHAIN (Types)) {
// Construct typeinfo object. Each call will produce a new expression
// even if duplicate.
tree TypeInfoNopExpr = (*lang_eh_runtime_type)(TREE_VALUE(Types));
// Produce value. Duplicate typeinfo get folded here.
Value *TypeInfo = Emit(TypeInfoNopExpr, 0);
// Capture typeinfo.
TypeInfos.push_back(cast<Constant>(TypeInfo));
}
}
} else if (TREE_CODE(exp) == STATEMENT_LIST) {
// Each statement in the statement list will be a catch, or none will.
for (tree_stmt_iterator I = tsi_start(exp); !tsi_end_p(I); tsi_next(&I))
GatherTypeInfo(tsi_stmt(I), TypeInfos);
} else {
assert(TypeInfos.empty() && "Need an exp with typeinfo");
}
}
/// AddLandingPad - Insert code to fetch and save the exception and exception
/// selector.
void TreeToLLVM::AddLandingPad() {
CreateExceptionValues();
// Fetch and store the exception.
Value *Ex = Builder.CreateCall(FuncEHException, "eh_ptr");
Builder.CreateStore(Ex, ExceptionValue);
// Fetch and store the exception selector.
std::vector<Value*> Args;
// The exception and the personality function.
Args.push_back(Builder.CreateLoad(ExceptionValue, "eh_ptr"));
Args.push_back(CastToType(Instruction::BitCast, FuncCPPPersonality,
PointerType::get(Type::Int8Ty)));
bool CaughtAll = false;
for (std::vector<EHScope>::reverse_iterator I = CurrentEHScopes.rbegin(),
E = CurrentEHScopes.rend(); I != E; ++I) {
if (I->CatchExpr) {
if (I->InfosType == Unknown) {
// Gather the type info and determine the catch type.
GatherTypeInfo(I->CatchExpr, I->TypeInfos);
I->InfosType = (TREE_CODE(I->CatchExpr) == STATEMENT_LIST &&
!tsi_end_p(tsi_start(I->CatchExpr)) &&
TREE_CODE(tsi_stmt(tsi_start(I->CatchExpr))) ==
EH_FILTER_EXPR) ? FilterExpr : CatchList;
}
if (I->InfosType == FilterExpr) {
// Filter - note the size.
Args.push_back(ConstantInt::get(Type::Int32Ty, I->TypeInfos.size()+1));
// An empty filter catches all exceptions.
if ((CaughtAll = !I->TypeInfos.size()))
break;
}
Args.reserve(Args.size() + I->TypeInfos.size());
for (unsigned j = 0, N = I->TypeInfos.size(); j < N; ++j) {
Args.push_back(I->TypeInfos[j]);
// A null typeinfo indicates a catch-all.
if ((CaughtAll = I->TypeInfos[j]->isNullValue()))
break;
}
}
}
// Invokes are required to branch to the unwind label no matter what exception
// is being unwound. Enforce this by appending a catch-all.
// FIXME: The use of null as catch-all is C++ specific.
if (!CaughtAll)
Args.push_back(Constant::getNullValue(PointerType::get(Type::Int8Ty)));
Value *Select = Builder.CreateCall(FuncEHSelector, Args.begin(), Args.end(),
"eh_select");
Builder.CreateStore(Select, ExceptionSelectorValue);
}
/// CreateExceptionValues - Create values used internally by exception handling.
///
void TreeToLLVM::CreateExceptionValues() {
// Check to see if the exception values have been constructed.
if (ExceptionValue) return;
const Type *IntPtr = TD.getIntPtrType();
ExceptionValue = CreateTemporary(PointerType::get(Type::Int8Ty));
ExceptionValue->setName("eh_exception");
ExceptionSelectorValue = CreateTemporary(IntPtr);
ExceptionSelectorValue->setName("eh_selector");
FuncEHException = Intrinsic::getDeclaration(TheModule,
Intrinsic::eh_exception);
FuncEHSelector = Intrinsic::getDeclaration(TheModule,
(IntPtr == Type::Int32Ty ?
Intrinsic::eh_selector_i32 :
Intrinsic::eh_selector_i64));
FuncEHGetTypeID = Intrinsic::getDeclaration(TheModule,
(IntPtr == Type::Int32Ty ?
Intrinsic::eh_typeid_for_i32 :
Intrinsic::eh_typeid_for_i64));
FuncCPPPersonality =
TheModule->getOrInsertFunction("__gxx_personality_v0",
Type::getPrimitiveType(Type::VoidTyID),
NULL);
FuncUnwindResume =
TheModule->getOrInsertFunction("_Unwind_Resume",
Type::getPrimitiveType(Type::VoidTyID),
PointerType::get(Type::Int8Ty),
NULL);
}
/// EmitProtectedCleanups - Wrap cleanups in a TRY_FILTER_EXPR that executes the
/// code specified by lang_protect_cleanup_actions if an exception is thrown.
void TreeToLLVM::EmitProtectedCleanups(tree cleanups) {
if (!lang_protect_cleanup_actions) {
Emit(cleanups, 0);
return;
}
if (CleanupFilter == NULL_TREE) {
// Create a catch-all filter that routes exceptions to the code specified
// by the lang_protect_cleanup_actions langhook.
// FIXME: the handler is supposed to be a "nothrow region". Support for
// this is blocked on support for nothrow functions.
tree filter = build (EH_FILTER_EXPR, void_type_node, NULL, NULL);
append_to_statement_list (lang_protect_cleanup_actions(),
&EH_FILTER_FAILURE (filter));
// CleanupFilter is the filter wrapped in a STATEMENT_LIST.
append_to_statement_list (filter, &CleanupFilter);
}
EmitTryInternal(cleanups, CleanupFilter, true);
}
/// EmitTRY_EXPR - Handle TRY_FINALLY_EXPR and TRY_CATCH_EXPR.
Value *TreeToLLVM::EmitTRY_EXPR(tree exp) {
return EmitTryInternal(TREE_OPERAND(exp, 0), TREE_OPERAND(exp, 1),
TREE_CODE(exp) == TRY_CATCH_EXPR);
}
/// EmitTryInternal - Handle TRY_FINALLY_EXPR and TRY_CATCH_EXPR given only the
/// expression operands. Done to avoid having EmitProtectedCleanups build a new
/// TRY_CATCH_EXPR for every cleanup block it wraps.
Value *TreeToLLVM::EmitTryInternal(tree inner, tree handler, bool isCatch) {
// The C++ front-end produces a lot of TRY_FINALLY_EXPR nodes that have empty
// try blocks. When these are seen, just emit the finally block directly for
// a small compile time speedup.
if (TREE_CODE(inner) == STATEMENT_LIST && tsi_end_p(tsi_start(inner))) {
if (isCatch)
return 0; // TRY_CATCH_EXPR with empty try block: nothing thrown.
// TRY_FINALLY_EXPR - Just run the finally block.
assert(!isCatch);
EmitProtectedCleanups(handler);
return 0;
}
// Remember that we are in this scope.
CurrentEHScopes.push_back(isCatch ? handler : NULL);
Emit(inner, 0);
assert(!isCatch || CurrentEHScopes.back().CatchExpr == handler
&& "Scope imbalance!");
// Emit a new block for the fall-through of the finally block.
BasicBlock *FinallyBlock = new BasicBlock("finally");
EmitBlock(FinallyBlock);
// Get the basic blocks in the current scope.
std::vector<BasicBlock*> BlocksInScope;
std::swap(CurrentEHScopes.back().Blocks, BlocksInScope);
// Get the fixups in the current scope.
std::vector<BranchFixup> BranchFixups;
std::swap(CurrentEHScopes.back().BranchFixups, BranchFixups);
// Remove the current scope. The state of the function is no longer in this
// scope.
CurrentEHScopes.pop_back();
// The finally fall-through block actually goes into the parent EH scope. We
// must emit things in this order so that EmitBlock can choose to nuke the
// previous block, and correctly nuke it from the nested scope.
if (!CurrentEHScopes.empty()) {
CurrentEHScopes.back().Blocks.push_back(FinallyBlock);
BlockEHScope[FinallyBlock] = CurrentEHScopes.size()-1;
} else {
BlockEHScope.erase(FinallyBlock);
}
// The finally block is not in the inner scope, it's actually in the outer
// one.
assert(BlocksInScope.back() == FinallyBlock);
BlocksInScope.pop_back();
// Give the FinallyBlock back a temporary terminator instruction.
new UnreachableInst(FinallyBlock);
// If the try block falls through (i.e. it doesn't end with a return), make
// sure to add a fixup on that edge if needed. If it falls through, EmitBlock
// would add a branch from the fall-through source to FinallyBlock, otherwise
// there will be no uses of it.
if (!FinallyBlock->use_empty()) {
BranchInst *BI = cast<BranchInst>(FinallyBlock->use_back());
assert(FinallyBlock->hasOneUse() && BI->isUnconditional() &&
"Unexpected behavior for EmitBlock");
// Add an extra branch fixup for the try fall-through.
BranchFixups.push_back(BranchFixup(BI, false));
}
// Loop over all of the fixups. If the fixup destination was in the current
// scope, then there is nothing to do and the fixup is done. Remove these.
for (unsigned i = 0, e = BranchFixups.size(); i != e; ++i) {
BasicBlock *DestBlock = BranchFixups[i].SrcBranch->getSuccessor(0);
std::map<BasicBlock*, unsigned>::iterator I = BlockEHScope.find(DestBlock);
if (I != BlockEHScope.end() && I->second == CurrentEHScopes.size()) {
BranchFixups[i] = BranchFixups.back();
BranchFixups.pop_back();
--i; --e;
continue;
}
// If this is a TRY_CATCH expression and the fixup isn't for an exception
// edge, punt the fixup up to the parent scope.
if (isCatch && !BranchFixups[i].isExceptionEdge) {
// Add the fixup to the parent cleanup scope if there is one.
if (!CurrentEHScopes.empty())
AddBranchFixup(BranchFixups[i].SrcBranch, false);
// Remove the fixup from this scope.
BranchFixups[i] = BranchFixups.back();
BranchFixups.pop_back();
--i; --e;
continue;
}
}
// Otherwise, the branch is to some block outside of the scope, which requires
// us to emit a copy of the finally code into the codepath.
while (!BranchFixups.empty()) {
BranchInst *FixupBr = BranchFixups.back().SrcBranch;
bool FixupIsExceptionEdge = BranchFixups.back().isExceptionEdge;
BranchFixups.pop_back();
// Okay, the destination is in a parent to this scope, which means that the
// branch fixup corresponds to an exit from this region. Expand the cleanup
// code then patch it into the code sequence.
// Add a basic block to emit the code into.
BasicBlock *CleanupBB = new BasicBlock("cleanup");
EmitBlock(CleanupBB);
// Provide exit point for cleanup code.
FinallyStack.push_back(FinallyBlock);
// Emit the code.
if (isCatch)
switch (TREE_CODE (tsi_stmt (tsi_start (handler)))) {
case CATCH_EXPR:
case EH_FILTER_EXPR:
Emit(handler, 0);
break;
default:
// Wrap the handler in a filter, like for TRY_FINALLY_EXPR, since this
// is what tree-eh.c does.
EmitProtectedCleanups(handler);
break;
}
else
EmitProtectedCleanups(handler);
// Clear exit point for cleanup code.
FinallyStack.pop_back();
// Because we can emit the same cleanup in more than one context, we must
// strip off LLVM information from the decls in the code. Otherwise, we
// will try to insert the same label into multiple places in the code.
StripLLVMTranslation(handler);
// Catches will supply own terminator.
if (!Builder.GetInsertBlock()->getTerminator()) {
// Emit a branch to the new target.
BranchInst *BI = Builder.CreateBr(FixupBr->getSuccessor(0));
// The old branch now goes to the cleanup block.
FixupBr->setSuccessor(0, CleanupBB);
// Fixup this new branch now.
FixupBr = BI;
// Add the fixup to the next cleanup scope if there is one.
if (!CurrentEHScopes.empty())
AddBranchFixup(FixupBr, FixupIsExceptionEdge);
} else {
// The old branch now goes to the cleanup block.
FixupBr->setSuccessor(0, CleanupBB);
}
}
// Move the finally block to the end of the function so we can continue
// emitting code into it.
Fn->getBasicBlockList().splice(Fn->end(), Fn->getBasicBlockList(),
FinallyBlock);
Builder.SetInsertPoint(FinallyBlock);
// Now that all of the cleanup blocks have been expanded, remove the temporary
// terminator we put on the FinallyBlock.
assert(isa<UnreachableInst>(FinallyBlock->getTerminator()));
FinallyBlock->getInstList().pop_back();
// Finally, remove the blocks in the scope from the BlockEHScope map.
for (unsigned i = 0, e = BlocksInScope.size(); i != e; ++i) {
bool Erased = BlockEHScope.erase(BlocksInScope[i]);
assert(Erased && "Block wasn't in map!");
}
return 0;
}
/// EmitCATCH_EXPR - Handle CATCH_EXPR.
///
Value *TreeToLLVM::EmitCATCH_EXPR(tree exp) {
#ifndef ITANIUM_STYLE_EXCEPTIONS
return 0;
#endif
// Make sure we have all the exception values in place.
CreateExceptionValues();
// Break out parts of catch.
tree Types = CATCH_TYPES(exp);
tree Body = CATCH_BODY(exp);
// Destinations of the catch entry conditions.
BasicBlock *ThenBlock = 0;
BasicBlock *ElseBlock = 0;
// FiXME - Determine last case so we don't need to emit test.
if (!Types) {
// Catch all - no testing required.
} else if (TREE_CODE(Types) != TREE_LIST) {
// Construct typeinfo object. Each call will produce a new expression
// even if duplicate.
tree TypeInfoNopExpr = (*lang_eh_runtime_type)(Types);
// Produce value. Duplicate typeinfo get folded here.
Value *TypeInfo = Emit(TypeInfoNopExpr, 0);
TypeInfo = BitCastToType(TypeInfo, PointerType::get(Type::Int8Ty));
// Call get eh type id.
Value *TypeID = Builder.CreateCall(FuncEHGetTypeID, TypeInfo,
"eh_typeid");
Value *Select = Builder.CreateLoad(ExceptionSelectorValue, "tmp");
// Compare with the exception selector.
Value *Compare = Builder.CreateICmpEQ(Select, TypeID, "tmp");
ThenBlock = new BasicBlock("eh_then");
ElseBlock = new BasicBlock("eh_else");
// Branch on the compare.
Builder.CreateCondBr(Compare, ThenBlock, ElseBlock);
} else {
ThenBlock = new BasicBlock("eh_then");
for (; Types; Types = TREE_CHAIN (Types)) {
if (ElseBlock) EmitBlock(ElseBlock);
// Construct typeinfo object. Each call will produce a new expression
// even if duplicate.
tree TypeInfoNopExpr = (*lang_eh_runtime_type)(TREE_VALUE(Types));
// Produce value. Duplicate typeinfo get folded here.
Value *TypeInfo = Emit(TypeInfoNopExpr, 0);
TypeInfo = BitCastToType(TypeInfo, PointerType::get(Type::Int8Ty));
// Call get eh type id.
Value *TypeID = Builder.CreateCall(FuncEHGetTypeID, TypeInfo,
"eh_typeid");
Value *Select = Builder.CreateLoad(ExceptionSelectorValue, "tmp");
// Compare with the exception selector.
Value *Compare = Builder.CreateICmpEQ(Select, TypeID, "tmp");
ElseBlock = new BasicBlock("eh_else");
// Branch on the compare.
Builder.CreateCondBr(Compare, ThenBlock, ElseBlock);
}
}
// Start the then block.
if (ThenBlock) EmitBlock(ThenBlock);
// Emit the body.
Emit(Body, 0);
// Branch to the try exit.
assert(!FinallyStack.empty() && "Need an exit point");
if (!Builder.GetInsertBlock()->getTerminator())
Builder.CreateBr(FinallyStack.back());
// Start the else block.
if (ElseBlock) EmitBlock(ElseBlock);
return 0;
}
/// EmitEXC_PTR_EXPR - Handle EXC_PTR_EXPR.
///
Value *TreeToLLVM::EmitEXC_PTR_EXPR(tree exp) {
#ifndef ITANIUM_STYLE_EXCEPTIONS
return 0;
#endif
// Load exception address.
CreateExceptionValues();
return Builder.CreateLoad(ExceptionValue, "eh_value");
}
/// EmitEH_FILTER_EXPR - Handle EH_FILTER_EXPR.
///
Value *TreeToLLVM::EmitEH_FILTER_EXPR(tree exp) {
#ifndef ITANIUM_STYLE_EXCEPTIONS
return 0;
#endif
CreateExceptionValues();
// The result of a filter landing pad will be a negative index if there is
// a match.
Value *Select = Builder.CreateLoad(ExceptionSelectorValue, "tmp");
// Compare with the filter action value.
Value *Zero = ConstantInt::get(Select->getType(), 0);
Value *Compare = Builder.CreateICmpSLT(Select, Zero, "tmp");
// Branch on the compare.
BasicBlock *FilterBB = new BasicBlock("filter");
BasicBlock *NoFilterBB = new BasicBlock("nofilter");
Builder.CreateCondBr(Compare, FilterBB, NoFilterBB);
EmitBlock(FilterBB);
Emit(EH_FILTER_FAILURE(exp), 0);
EmitBlock(NoFilterBB);
return 0;
}
//===----------------------------------------------------------------------===//
// ... Expressions ...
//===----------------------------------------------------------------------===//
/// EmitINTEGER_CST_Aggregate - The C++ front-end abuses INTEGER_CST nodes to
/// represent empty classes. For now we check that this is the case we handle,
/// then zero out DestLoc.
///
/// FIXME: When merged with mainline, remove this code. The C++ front-end has
/// been fixed.
///
void TreeToLLVM::EmitINTEGER_CST_Aggregate(tree exp, Value *DestLoc) {
tree type = TREE_TYPE(exp);
#ifndef NDEBUG
assert(TREE_CODE(type) == RECORD_TYPE && "Not an empty class!");
for (tree F = TYPE_FIELDS(type); F; F = TREE_CHAIN(F))
assert(TREE_CODE(F) != FIELD_DECL && "Not an empty struct/class!");
#endif
EmitAggregateZero(DestLoc, type);
}
/// EmitLoadOfLValue - When an l-value expression is used in a context that
/// requires an r-value, this method emits the lvalue computation, then loads
/// the result.
Value *TreeToLLVM::EmitLoadOfLValue(tree exp, Value *DestLoc) {
// If this is an SSA value, don't emit a load, just use the result.
if (isGCC_SSA_Temporary(exp)) {
assert(DECL_LLVM_SET_P(exp) && "Definition not found before use!");
return DECL_LLVM(exp);
} else if (TREE_CODE(exp) == VAR_DECL && DECL_REGISTER(exp) &&
TREE_STATIC(exp)) {
// If this is a register variable, EmitLV can't handle it (there is no
// l-value of a register variable). Emit an inline asm node that copies the
// value out of the specified register.
return EmitReadOfRegisterVariable(exp, DestLoc);
}
LValue LV = EmitLV(exp);
bool isVolatile = TREE_THIS_VOLATILE(exp);
const Type *Ty = ConvertType(TREE_TYPE(exp));
unsigned Alignment = expr_align(exp) / 8;
if (!LV.isBitfield()) {
if (!DestLoc) {
// Scalar value: emit a load.
Value *Ptr = CastToType(Instruction::BitCast, LV.Ptr,
PointerType::get(Ty));
LoadInst *LI = Builder.CreateLoad(Ptr, isVolatile, "tmp");
LI->setAlignment(Alignment);
return LI;
} else {
EmitAggregateCopy(DestLoc, LV.Ptr, TREE_TYPE(exp), false, isVolatile,
Alignment);
return 0;
}
} else {
// This is a bitfield reference.
LoadInst *LI = Builder.CreateLoad(LV.Ptr, isVolatile, "tmp");
LI->setAlignment(Alignment);
Value *Val = LI;
unsigned ValSizeInBits = Val->getType()->getPrimitiveSizeInBits();
assert(Val->getType()->isInteger() && "Invalid bitfield lvalue!");
assert(ValSizeInBits >= LV.BitSize && "Bad bitfield lvalue!");
assert(ValSizeInBits >= LV.BitSize+LV.BitStart && "Bad bitfield lvalue!");
// Mask the bits out by shifting left first, then shifting right. The
// LLVM optimizer will turn this into an AND if this is an unsigned
// expression.
// If this target has bitfields laid out in big-endian order, invert the bit
// in the word if needed.
if (BITS_BIG_ENDIAN)
LV.BitStart = ValSizeInBits-LV.BitStart-LV.BitSize;
if (LV.BitStart+LV.BitSize != ValSizeInBits) {
Value *ShAmt = ConstantInt::get(Val->getType(),
ValSizeInBits-(LV.BitStart+LV.BitSize));
Val = Builder.CreateShl(Val, ShAmt, "tmp");
}
// Shift right required?
if (ValSizeInBits-LV.BitSize) {
Value *ShAmt = ConstantInt::get(Val->getType(), ValSizeInBits-LV.BitSize);
if (TYPE_UNSIGNED(TREE_TYPE(exp)))
Val = Builder.CreateLShr(Val, ShAmt, "tmp");
else
Val = Builder.CreateAShr(Val, ShAmt, "tmp");
}
if (TYPE_UNSIGNED(TREE_TYPE(exp)))
return CastToUIntType(Val, Ty);
else
return CastToSIntType(Val, Ty);
}
}
Value *TreeToLLVM::EmitADDR_EXPR(tree exp) {
LValue LV = EmitLV(TREE_OPERAND(exp, 0));
assert((!LV.isBitfield() || LV.BitStart == 0) &&
"It is illegal to take the address of a bitfield");
// Perform a cast here if necessary. For example, GCC sometimes forms an
// ADDR_EXPR where the operand is an array, and the ADDR_EXPR type is a
// pointer to the first element.
return CastToType(Instruction::BitCast, LV.Ptr, ConvertType(TREE_TYPE(exp)));
}
Value *TreeToLLVM::EmitOBJ_TYPE_REF(tree exp) {
return CastToType(Instruction::BitCast, Emit(OBJ_TYPE_REF_EXPR(exp), 0),
ConvertType(TREE_TYPE(exp)));
}
Value *TreeToLLVM::EmitCALL_EXPR(tree exp, Value *DestLoc) {
// Check for a built-in function call. If we can lower it directly, do so
// now.
tree fndecl = get_callee_fndecl(exp);
if (fndecl && DECL_BUILT_IN(fndecl) &&
DECL_BUILT_IN_CLASS(fndecl) != BUILT_IN_FRONTEND) {
Value *Res = 0;
if (EmitBuiltinCall(exp, fndecl, DestLoc, Res))
return Res;
}
Value *Callee = Emit(TREE_OPERAND(exp, 0), 0);
if (TREE_OPERAND(exp, 2)) {
// This is a direct call to a function using a static chain. We need to
// change the function type to one with an extra parameter for the chain.
assert(fndecl && "Indirect static chain call!");
tree function_type = TYPE_MAIN_VARIANT(TREE_TYPE(fndecl));
tree static_chain = TREE_OPERAND(exp, 2);
unsigned CallingConv;
const Type *Ty = TheTypeConverter->ConvertFunctionType(function_type,
fndecl,
static_chain,
CallingConv);
Callee = CastToType(Instruction::BitCast, Callee, PointerType::get(Ty));
}
//EmitCall(exp, DestLoc);
Value *Result = EmitCallOf(Callee, exp, DestLoc);
// If the function has the volatile bit set, then it is a "noreturn" function.
// Output an unreachable instruction right after the function to prevent LLVM
// from thinking that control flow will fall into the subsequent block.
//
if (fndecl && TREE_THIS_VOLATILE(fndecl)) {
Builder.CreateUnreachable();
EmitBlock(new BasicBlock(""));
}
return Result;
}
namespace {
/// FunctionCallArgumentConversion - This helper class is driven by the ABI
/// definition for this target to figure out how to pass arguments into the
/// stack/regs for a function call.
struct FunctionCallArgumentConversion : public DefaultABIClient {
tree CallExpression;
SmallVector<Value*, 16> &CallOperands;
CallingConv::ID &CallingConvention;
bool isStructRet;
LLVMBuilder &Builder;
Value *DestLoc;
std::vector<Value*> LocStack;
FunctionCallArgumentConversion(tree exp, SmallVector<Value*, 16> &ops,
CallingConv::ID &cc,
LLVMBuilder &b, Value *destloc)
: CallExpression(exp), CallOperands(ops), CallingConvention(cc),
Builder(b), DestLoc(destloc) {
CallingConvention = CallingConv::C;
isStructRet = false;
#ifdef TARGET_ADJUST_LLVM_CC
tree ftype;
if (tree fdecl = get_callee_fndecl(exp)) {
ftype = TREE_TYPE(fdecl);
} else {
ftype = TREE_TYPE(TREE_OPERAND(exp,0));
// If it's call to pointer, we look for the function type.
if (TREE_CODE(ftype) == POINTER_TYPE)
ftype = TREE_TYPE(ftype);
}
TARGET_ADJUST_LLVM_CC(CallingConvention, ftype);
#endif
}
void setLocation(Value *Loc) {
LocStack.push_back(Loc);
}
void clear() {
assert(LocStack.size() == 1 && "Imbalance!");
LocStack.clear();
}
/// HandleScalarResult - This callback is invoked if the function returns a
/// simple scalar result value.
void HandleScalarResult(const Type *RetTy) {
// There is nothing to do here if we return a scalar or void.
assert(DestLoc == 0 &&
"Call returns a scalar but caller expects aggregate!");
}
/// HandleAggregateResultAsScalar - This callback is invoked if the function
/// returns an aggregate value by bit converting it to the specified scalar
/// type and returning that.
void HandleAggregateResultAsScalar(const Type *ScalarTy) {
// There is nothing to do here.
}
/// HandleAggregateShadowArgument - This callback is invoked if the function
/// returns an aggregate value by using a "shadow" first parameter. If
/// RetPtr is set to true, the pointer argument itself is returned from the
/// function.
void HandleAggregateShadowArgument(const PointerType *PtrArgTy,
bool RetPtr) {
// Make sure this call is marked as 'struct return'.
isStructRet = true;
// If the front-end has already made the argument explicit, don't do it
// again.
if (CALL_EXPR_HAS_RETURN_SLOT_ADDR(CallExpression))
return;
// Otherwise, we need to pass a buffer to return into. If the caller uses
// the result, DestLoc will be set. If it ignores it, it could be unset,
// in which case we need to create a dummy buffer.
if (DestLoc == 0)
DestLoc = TheTreeToLLVM->CreateTemporary(PtrArgTy->getElementType());
else
assert(PtrArgTy == DestLoc->getType());
CallOperands.push_back(DestLoc);
}
void HandleScalarArgument(const llvm::Type *LLVMTy, tree type) {
assert(!LocStack.empty());
Value *Loc = LocStack.back();
if (cast<PointerType>(Loc->getType())->getElementType() != LLVMTy)
// This always deals with pointer types so BitCast is appropriate
Loc = Builder.CreateBitCast(Loc, PointerType::get(LLVMTy), "tmp");
CallOperands.push_back(Builder.CreateLoad(Loc, "tmp"));
}
void EnterField(unsigned FieldNo, const llvm::Type *StructTy) {
Constant *Zero = Constant::getNullValue(Type::Int32Ty);
Constant *FIdx = ConstantInt::get(Type::Int32Ty, FieldNo);
Value *Loc = LocStack.back();
if (cast<PointerType>(Loc->getType())->getElementType() != StructTy)
// This always deals with pointer types so BitCast is appropriate
Loc = Builder.CreateBitCast(Loc, PointerType::get(StructTy), "tmp");
Value *Idxs[2] = { Zero, FIdx };
LocStack.push_back(Builder.CreateGEP(Loc, Idxs, Idxs + 2, "tmp"));
}
void ExitField() {
LocStack.pop_back();
}
};
}
/// EmitCallOf - Emit a call to the specified callee with the operands specified
/// in the CALL_EXP 'exp'. If the result of the call is a scalar, return the
/// result, otherwise store it in DestLoc.
Value *TreeToLLVM::EmitCallOf(Value *Callee, tree exp, Value *DestLoc) {
// Determine if we need to generate an invoke instruction (instead of a simple
// call) and if so, what the exception destination will be.
BasicBlock *UnwindBlock = 0;
// Do not turn intrinsic calls or no-throw calls into invokes.
if ((!isa<Function>(Callee) || !cast<Function>(Callee)->getIntrinsicID()) &&
// Turn calls that throw that are inside of a cleanup scope into invokes.
!CurrentEHScopes.empty() && tree_could_throw_p(exp)) {
if (UnwindBB == 0)
UnwindBB = new BasicBlock("Unwind");
UnwindBlock = UnwindBB;
}
SmallVector<Value*, 16> CallOperands;
CallingConv::ID CallingConvention;
FunctionCallArgumentConversion Client(exp, CallOperands, CallingConvention,
Builder, DestLoc);
TheLLVMABI<FunctionCallArgumentConversion> ABIConverter(Client);
// Handle the result, including struct returns.
ABIConverter.HandleReturnType(TREE_TYPE(exp));
// Pass the static chain, if any, as the first parameter.
if (TREE_OPERAND(exp, 2))
CallOperands.push_back(Emit(TREE_OPERAND(exp, 2), 0));
// Loop over the arguments, expanding them and adding them to the op list.
const PointerType *PFTy = cast<PointerType>(Callee->getType());
const FunctionType *FTy = cast<FunctionType>(PFTy->getElementType());
for (tree arg = TREE_OPERAND(exp, 1); arg; arg = TREE_CHAIN(arg)) {
const Type *ActualArgTy = ConvertType(TREE_TYPE(TREE_VALUE(arg)));
const Type *ArgTy = ActualArgTy;
if (CallOperands.size() < FTy->getNumParams())
ArgTy = FTy->getParamType(CallOperands.size());
// If we are implicitly passing the address of this argument instead of
// passing it by value, handle this first.
if (isPassedByInvisibleReference(TREE_TYPE(TREE_VALUE(arg)))) {
// Get the address of the parameter passed in.
LValue ArgVal = EmitLV(TREE_VALUE(arg));
assert(!ArgVal.isBitfield() && "Bitfields shouldn't be invisible refs!");
Value *Ptr = ArgVal.Ptr;
if (CallOperands.size() >= FTy->getNumParams())
ArgTy = PointerType::get(ArgTy);
CallOperands.push_back(CastToType(Instruction::BitCast, Ptr, ArgTy));
} else if (ActualArgTy->isFirstClassType()) {
Value *V = Emit(TREE_VALUE(arg), 0);
bool isSigned = !TYPE_UNSIGNED(TREE_TYPE(TREE_VALUE(arg)));
CallOperands.push_back(CastToAnyType(V, isSigned, ArgTy, false));
} else {
// If this is an aggregate value passed by-value, use the current ABI to
// determine how the parameters are passed.
LValue LV = EmitLV(TREE_VALUE(arg));
assert(!LV.isBitfield() && "Bitfields are first-class types!");
Client.setLocation(LV.Ptr);
ABIConverter.HandleArgument(TREE_TYPE(TREE_VALUE(arg)));
}
}
// Compile stuff like:
// %tmp = call float (...)* bitcast (float ()* @foo to float (...)*)( )
// to:
// %tmp = call float @foo( )
// This commonly occurs due to C "implicit ..." semantics.
if (ConstantExpr *CE = dyn_cast<ConstantExpr>(Callee)) {
if (CallOperands.empty() && CE->getOpcode() == Instruction::BitCast) {
Constant *RealCallee = CE->getOperand(0);
assert(isa<PointerType>(RealCallee->getType()) &&
"Bitcast to ptr not from ptr?");
const PointerType *RealPT = cast<PointerType>(RealCallee->getType());
if (const FunctionType *RealFT =
dyn_cast<FunctionType>(RealPT->getElementType())) {
const PointerType *ActualPT = cast<PointerType>(Callee->getType());
const FunctionType *ActualFT =
cast<FunctionType>(ActualPT->getElementType());
if (RealFT->getReturnType() == ActualFT->getReturnType() &&
ActualFT->getNumParams() == 0)
Callee = RealCallee;
}
}
}
Value *Call;
if (!UnwindBlock) {
Call = Builder.CreateCall(Callee, CallOperands.begin(), CallOperands.end());
cast<CallInst>(Call)->setCallingConv(CallingConvention);
} else {
BasicBlock *NextBlock = new BasicBlock("invcont");
Call = Builder.CreateInvoke(Callee, NextBlock, UnwindBlock,
CallOperands.begin(), CallOperands.end());
cast<InvokeInst>(Call)->setCallingConv(CallingConvention);
// Lazily create an unwind block for this scope, which we can emit a fixup
// branch in.
if (CurrentEHScopes.back().UnwindBlock == 0) {
EmitBlock(CurrentEHScopes.back().UnwindBlock = new BasicBlock("unwind"));
#ifdef ITANIUM_STYLE_EXCEPTIONS
// Add landing pad entry code.
AddLandingPad();
#endif
// This branch to the unwind edge should have exception cleanups
// inserted onto it.
EmitBranchInternal(UnwindBlock, true);
}
cast<InvokeInst>(Call)->setUnwindDest(CurrentEHScopes.back().UnwindBlock);
EmitBlock(NextBlock);
}
if (Call->getType() == Type::VoidTy)
return 0;
Call->setName("tmp");
// If the caller expects an aggregate, we have a situation where the ABI for
// the current target specifies that the aggregate be returned in scalar
// registers even though it is an aggregate. We must bitconvert the scalar
// to the destination aggregate type. We do this by casting the DestLoc
// pointer and storing into it.
if (!DestLoc)
return Call; // Normal scalar return.
DestLoc = BitCastToType(DestLoc, PointerType::get(Call->getType()));
Builder.CreateStore(Call, DestLoc);
return 0;
}
/// HandleMultiplyDefinedGCCTemp - GCC temporaries are *mostly* single
/// definition, and always have all uses dominated by the definition. In cases
/// where the temporary has multiple uses, we will first see the initial
/// definition, some uses of that definition, then subsequently see another
/// definition with uses of this second definition.
///
/// Because LLVM temporaries *must* be single definition, when we see the second
/// definition, we actually change the temporary to mark it as not being a GCC
/// temporary anymore. We then create an alloca for it, initialize it with the
/// first value seen, then treat it as a normal variable definition.
///
void TreeToLLVM::HandleMultiplyDefinedGCCTemp(tree Var) {
Value *FirstVal = DECL_LLVM(Var);
// Create a new temporary and set the VAR_DECL to use it as the llvm location.
Value *NewTmp = CreateTemporary(FirstVal->getType());
SET_DECL_LLVM(Var, NewTmp);
// Store the already existing initial value into the alloca. If the value
// being stored is an instruction, emit the store right after the instruction,
// otherwise, emit it into the entry block.
StoreInst *SI = new StoreInst(FirstVal, NewTmp);
BasicBlock::iterator InsertPt;
if (Instruction *I = dyn_cast<Instruction>(FirstVal)) {
InsertPt = I; // Insert after the init instruction.
// If the instruction is an alloca in the entry block, the insert point
// will be before the alloca. Advance to the AllocaInsertionPoint if we are
// before it.
if (I->getParent() == &Fn->front()) {
for (BasicBlock::iterator CI = InsertPt, E = Fn->begin()->end();
CI != E; ++CI) {
if (&*CI == AllocaInsertionPoint) {
InsertPt = AllocaInsertionPoint;
break;
}
}
}
// If the instruction is an invoke, the init is inserted on the normal edge.
if (InvokeInst *II = dyn_cast<InvokeInst>(I)) {
InsertPt = II->getNormalDest()->begin();
while (isa<PHINode>(InsertPt))
++InsertPt;
}
} else {
InsertPt = AllocaInsertionPoint; // Insert after the allocas.
}
BasicBlock *BB = InsertPt->getParent();
BB->getInstList().insert(++InsertPt, SI);
// Finally, This is no longer a GCC temporary.
DECL_GIMPLE_FORMAL_TEMP_P(Var) = 0;
}
/// EmitMODIFY_EXPR - Note that MODIFY_EXPRs are rvalues only!
///
Value *TreeToLLVM::EmitMODIFY_EXPR(tree exp, Value *DestLoc) {
// If this is the definition of an SSA variable, set its DECL_LLVM to the
// RHS.
bool Op0Signed = !TYPE_UNSIGNED(TREE_TYPE(TREE_OPERAND(exp, 0)));
bool Op1Signed = !TYPE_UNSIGNED(TREE_TYPE(TREE_OPERAND(exp, 1)));
if (isGCC_SSA_Temporary(TREE_OPERAND(exp, 0))) {
// If DECL_LLVM is already set, this is a multiply defined GCC temporary.
if (DECL_LLVM_SET_P(TREE_OPERAND(exp, 0))) {
HandleMultiplyDefinedGCCTemp(TREE_OPERAND(exp, 0));
return EmitMODIFY_EXPR(exp, DestLoc);
}
Value *RHS = Emit(TREE_OPERAND(exp, 1), 0);
RHS = CastToAnyType(RHS, Op1Signed,
ConvertType(TREE_TYPE(TREE_OPERAND(exp, 0))),
Op0Signed);
SET_DECL_LLVM(TREE_OPERAND(exp, 0), RHS);
return RHS;
} else if (TREE_CODE(TREE_OPERAND(exp, 0)) == VAR_DECL &&
DECL_REGISTER(TREE_OPERAND(exp, 0)) &&
TREE_STATIC(TREE_OPERAND(exp, 0))) {
// If this is a store to a register variable, EmitLV can't handle the dest
// (there is no l-value of a register variable). Emit an inline asm node
// that copies the value into the specified register.
Value *RHS = Emit(TREE_OPERAND(exp, 1), 0);
RHS = CastToAnyType(RHS, Op1Signed,
ConvertType(TREE_TYPE(TREE_OPERAND(exp, 0))),
Op0Signed);
EmitModifyOfRegisterVariable(TREE_OPERAND(exp, 0), RHS);
return RHS;
}
LValue LV = EmitLV(TREE_OPERAND(exp, 0));
bool isVolatile = TREE_THIS_VOLATILE(TREE_OPERAND(exp, 0));
unsigned Alignment = expr_align(TREE_OPERAND(exp, 0)) / 8;
if (!LV.isBitfield()) {
const Type *ValTy = ConvertType(TREE_TYPE(TREE_OPERAND(exp, 1)));
if (ValTy->isFirstClassType()) {
// Non-bitfield, scalar value. Just emit a store.
Value *RHS = Emit(TREE_OPERAND(exp, 1), 0);
// Convert RHS to the right type if we can, otherwise convert the pointer.
const PointerType *PT = cast<PointerType>(LV.Ptr->getType());
if (PT->getElementType()->canLosslesslyBitCastTo(RHS->getType()))
RHS = CastToAnyType(RHS, Op1Signed, PT->getElementType(), Op0Signed);
else
LV.Ptr = BitCastToType(LV.Ptr, PointerType::get(RHS->getType()));
StoreInst *SI = Builder.CreateStore(RHS, LV.Ptr, isVolatile);
SI->setAlignment(Alignment);
return RHS;
}
// Non-bitfield aggregate value.
if (DestLoc) {
Emit(TREE_OPERAND(exp, 1), LV.Ptr);
EmitAggregateCopy(DestLoc, LV.Ptr, TREE_TYPE(exp), isVolatile, false,
Alignment);
} else if (!isVolatile) {
Emit(TREE_OPERAND(exp, 1), LV.Ptr);
} else {
// Need to do a volatile store into TREE_OPERAND(exp, 1). To do this, we
// emit it into a temporary memory location, then do a volatile copy into
// the real destination. This is probably suboptimal in some cases, but
// it gets the volatile memory access right. It would be better if the
// destloc pointer of 'Emit' had a flag that indicated it should be
// volatile.
Value *Tmp = CreateTemporary(ConvertType(TREE_TYPE(TREE_OPERAND(exp,1))));
Emit(TREE_OPERAND(exp, 1), Tmp);
EmitAggregateCopy(LV.Ptr, Tmp, TREE_TYPE(TREE_OPERAND(exp,1)),
isVolatile, false, Alignment);
}
return 0;
}
// Last case, this is a store to a bitfield, so we have to emit a
// read/modify/write sequence.
LoadInst *LI = Builder.CreateLoad(LV.Ptr, isVolatile, "tmp");
LI->setAlignment(Alignment);
Value *OldVal = LI;
// If the target is big-endian, invert the bit in the word.
unsigned ValSizeInBits = TD.getTypeSize(OldVal->getType())*8;
if (BITS_BIG_ENDIAN)
LV.BitStart = ValSizeInBits-LV.BitStart-LV.BitSize;
// If not storing into the zero'th bit, shift the Src value to the left.
Value *RHS = Emit(TREE_OPERAND(exp, 1), 0);
Value *RetVal = RHS;
RHS = CastToAnyType(RHS, Op1Signed, OldVal->getType(), Op0Signed);
if (LV.BitStart)
RHS = Builder.CreateShl(RHS, ConstantInt::get(RHS->getType(), LV.BitStart),
"tmp");
// Next, if this doesn't touch the top bit, mask out any bits that shouldn't
// be set in the result.
uint64_t MaskVal = ((1ULL << LV.BitSize)-1) << LV.BitStart;
Constant *Mask = ConstantInt::get(Type::Int64Ty, MaskVal);
Mask = ConstantExpr::getTruncOrBitCast(Mask, RHS->getType());
if (LV.BitStart+LV.BitSize != ValSizeInBits)
RHS = Builder.CreateAnd(RHS, Mask, "tmp");
// Next, mask out the bits this bit-field should include from the old value.
Mask = ConstantExpr::getNot(Mask);
OldVal = Builder.CreateAnd(OldVal, Mask, "tmp");
// Finally, merge the two together and store it.
Value *Val = Builder.CreateOr(OldVal, RHS, "tmp");
StoreInst *SI = Builder.CreateStore(Val, LV.Ptr, isVolatile);
SI->setAlignment(Alignment);
return RetVal;
}
Value *TreeToLLVM::EmitNOP_EXPR(tree exp, Value *DestLoc) {
if (TREE_CODE(TREE_TYPE(exp)) == VOID_TYPE && // deleted statement.
TREE_CODE(TREE_OPERAND(exp, 0)) == INTEGER_CST)
return 0;
tree Op = TREE_OPERAND(exp, 0);
const Type *Ty = ConvertType(TREE_TYPE(exp));
bool OpIsSigned = !TYPE_UNSIGNED(TREE_TYPE(Op));
bool ExpIsSigned = !TYPE_UNSIGNED(TREE_TYPE(exp));
if (DestLoc == 0) {
// Scalar to scalar copy.
assert(!isAggregateTreeType(TREE_TYPE(Op))
&& "Aggregate to scalar nop_expr!");
Value *OpVal = Emit(Op, DestLoc);
if (Ty == Type::VoidTy) return 0;
return CastToAnyType(OpVal, OpIsSigned, Ty, ExpIsSigned);
} else if (isAggregateTreeType(TREE_TYPE(Op))) {
// Aggregate to aggregate copy.
DestLoc = CastToType(Instruction::BitCast, DestLoc, PointerType::get(Ty));
Value *OpVal = Emit(Op, DestLoc);
assert(OpVal == 0 && "Shouldn't cast scalar to aggregate!");
return 0;
}
// Scalar to aggregate copy.
Value *OpVal = Emit(Op, 0);
DestLoc = CastToType(Instruction::BitCast, DestLoc,
PointerType::get(OpVal->getType()));
Builder.CreateStore(OpVal, DestLoc);
return 0;
}
Value *TreeToLLVM::EmitCONVERT_EXPR(tree exp, Value *DestLoc) {
assert(!DestLoc && "Cannot handle aggregate casts!");
Value *Op = Emit(TREE_OPERAND(exp, 0), 0);
bool OpIsSigned = !TYPE_UNSIGNED(TREE_TYPE(TREE_OPERAND(exp, 0)));
bool ExpIsSigned = !TYPE_UNSIGNED(TREE_TYPE(exp));
return CastToAnyType(Op, OpIsSigned, ConvertType(TREE_TYPE(exp)),ExpIsSigned);
}
Value *TreeToLLVM::EmitVIEW_CONVERT_EXPR(tree exp, Value *DestLoc) {
tree Op = TREE_OPERAND(exp, 0);
if (isAggregateTreeType(TREE_TYPE(Op))) {
const Type *OpTy = ConvertType(TREE_TYPE(Op));
Value *Target = DestLoc ?
// This is an aggregate-to-agg VIEW_CONVERT_EXPR, just evaluate in place.
CastToType(Instruction::BitCast, DestLoc, PointerType::get(OpTy)) :
// This is an aggregate-to-scalar VIEW_CONVERT_EXPR, evaluate, then load.
CreateTemporary(OpTy);
switch (TREE_CODE(Op)) {
default: {
Value *OpVal = Emit(Op, Target);
assert(OpVal == 0 && "Expected an aggregate operand!");
break;
}
// Lvalues
case VAR_DECL:
case PARM_DECL:
case RESULT_DECL:
case INDIRECT_REF:
case ARRAY_REF:
case ARRAY_RANGE_REF:
case COMPONENT_REF:
case BIT_FIELD_REF:
case STRING_CST:
case REALPART_EXPR:
case IMAGPART_EXPR:
// Same as EmitLoadOfLValue but taking the size from TREE_TYPE(exp), since
// the size of TREE_TYPE(Op) may not be available.
LValue LV = EmitLV(Op);
assert(!LV.isBitfield() && "Expected an aggregate operand!");
bool isVolatile = TREE_THIS_VOLATILE(Op);
unsigned Alignment = expr_align(Op) / 8;
EmitAggregateCopy(Target, LV.Ptr, TREE_TYPE(exp), false, isVolatile,
Alignment);
break;
}
if (DestLoc)
return 0;
const Type *ExpTy = ConvertType(TREE_TYPE(exp));
return Builder.CreateLoad(CastToType(Instruction::BitCast, Target,
PointerType::get(ExpTy)), "tmp");
}
if (DestLoc) {
// The input is a scalar the output is an aggregate, just eval the input,
// then store into DestLoc.
Value *OpVal = Emit(Op, 0);
assert(OpVal && "Expected a scalar result!");
DestLoc = CastToType(Instruction::BitCast, DestLoc,
PointerType::get(OpVal->getType()));
Builder.CreateStore(OpVal, DestLoc);
return 0;
}
// Otherwise, this is a scalar to scalar conversion.
Value *OpVal = Emit(Op, 0);
assert(OpVal && "Expected a scalar result!");
const Type *DestTy = ConvertType(TREE_TYPE(exp));
// If the source is a pointer, use ptrtoint to get it to something
// bitcast'able. This supports things like v_c_e(foo*, float).
if (isa<PointerType>(OpVal->getType())) {
if (isa<PointerType>(DestTy)) // ptr->ptr is a simple bitcast.
return Builder.CreateBitCast(OpVal, DestTy, "tmp");
// Otherwise, ptrtoint to intptr_t first.
OpVal = Builder.CreatePtrToInt(OpVal, TD.getIntPtrType(), "tmp");
}
// If the destination type is a pointer, use inttoptr.
if (isa<PointerType>(DestTy))
return Builder.CreateIntToPtr(OpVal, DestTy, "tmp");
// Otherwise, use a bitcast.
return Builder.CreateBitCast(OpVal, DestTy, "tmp");
}
Value *TreeToLLVM::EmitNEGATE_EXPR(tree exp, Value *DestLoc) {
if (!DestLoc)
return Builder.CreateNeg(Emit(TREE_OPERAND(exp, 0), 0), "tmp");
// Emit the operand to a temporary.
const Type *ComplexTy=cast<PointerType>(DestLoc->getType())->getElementType();
Value *Tmp = CreateTemporary(ComplexTy);
Emit(TREE_OPERAND(exp, 0), Tmp);
// Handle complex numbers: -(a+ib) = -a + i*-b
Value *R, *I;
EmitLoadFromComplex(R, I, Tmp, TREE_THIS_VOLATILE(TREE_OPERAND(exp, 0)));
R = Builder.CreateNeg(R, "tmp");
I = Builder.CreateNeg(I, "tmp");
EmitStoreToComplex(DestLoc, R, I, false);
return 0;
}
Value *TreeToLLVM::EmitCONJ_EXPR(tree exp, Value *DestLoc) {
assert(DestLoc && "CONJ_EXPR only applies to complex numbers.");
// Emit the operand to a temporary.
const Type *ComplexTy=cast<PointerType>(DestLoc->getType())->getElementType();
Value *Tmp = CreateTemporary(ComplexTy);
Emit(TREE_OPERAND(exp, 0), Tmp);
// Handle complex numbers: ~(a+ib) = a + i*-b
Value *R, *I;
EmitLoadFromComplex(R, I, Tmp, TREE_THIS_VOLATILE(TREE_OPERAND(exp, 0)));
I = Builder.CreateNeg(I, "tmp");
EmitStoreToComplex(DestLoc, R, I, false);
return 0;
}
Value *TreeToLLVM::EmitABS_EXPR(tree exp) {
Value *Op = Emit(TREE_OPERAND(exp, 0), 0);
if (!Op->getType()->isFloatingPoint()) {
Instruction *OpN = Builder.CreateNeg(Op, (Op->getName()+"neg").c_str());
ICmpInst::Predicate pred = TYPE_UNSIGNED(TREE_TYPE(TREE_OPERAND(exp, 0))) ?
ICmpInst::ICMP_UGE : ICmpInst::ICMP_SGE;
Value *Cmp = Builder.CreateICmp(pred, Op, OpN->getOperand(0), "abscond");
return Builder.CreateSelect(Cmp, Op, OpN, "abs");
} else {
// Turn FP abs into fabs/fabsf.
return EmitBuiltinUnaryFPOp(Op, "fabsf", "fabs");
}
}
Value *TreeToLLVM::EmitBIT_NOT_EXPR(tree exp) {
Value *Op = Emit(TREE_OPERAND(exp, 0), 0);
if (isa<PointerType>(Op->getType())) {
assert (TREE_CODE(TREE_TYPE(exp)) == INTEGER_TYPE &&
"Expected integer type here");
Op = CastToType(Instruction::PtrToInt, Op, TREE_TYPE(exp));
}
return Builder.CreateNot(Op, (Op->getName()+"not").c_str());
}
Value *TreeToLLVM::EmitTRUTH_NOT_EXPR(tree exp) {
Value *V = Emit(TREE_OPERAND(exp, 0), 0);
if (V->getType() != Type::Int1Ty)
V = Builder.CreateICmpNE(V, Constant::getNullValue(V->getType()), "toBool");
V = Builder.CreateNot(V, (V->getName()+"not").c_str());
return CastToUIntType(V, ConvertType(TREE_TYPE(exp)));
}
/// EmitCompare - 'exp' is a comparison of two values. Opc is the base LLVM
/// comparison to use. isUnord is true if this is a floating point comparison
/// that should also be true if either operand is a NaN. Note that Opc can be
/// set to zero for special cases.
Value *TreeToLLVM::EmitCompare(tree exp, unsigned UIOpc, unsigned SIOpc,
unsigned FPPred) {
// Get the type of the operands
tree Op0Ty = TREE_TYPE(TREE_OPERAND(exp,0));
// Deal with complex types
if (TREE_CODE(Op0Ty) == COMPLEX_TYPE)
return EmitComplexBinOp(exp, 0); // Complex ==/!=
// Get the compare operands, in the right type. Comparison of struct is not
// allowed, so this is safe as we already handled complex (struct) type.
Value *LHS = Emit(TREE_OPERAND(exp, 0), 0);
Value *RHS = Emit(TREE_OPERAND(exp, 1), 0);
bool LHSIsSigned = !TYPE_UNSIGNED(TREE_TYPE(TREE_OPERAND(exp, 0)));
bool RHSIsSigned = !TYPE_UNSIGNED(TREE_TYPE(TREE_OPERAND(exp, 1)));
RHS = CastToAnyType(RHS, RHSIsSigned, LHS->getType(), LHSIsSigned);
assert(LHS->getType() == RHS->getType() && "Binop type equality failure!");
// Handle the integer/pointer cases
if (!FLOAT_TYPE_P(Op0Ty)) {
// Determine which predicate to use based on signedness
ICmpInst::Predicate pred =
ICmpInst::Predicate(TYPE_UNSIGNED(Op0Ty) ? UIOpc : SIOpc);
// Get the compare instructions
Value *Result = Builder.CreateICmp(pred, LHS, RHS, "tmp");
// The GCC type is probably an int, not a bool.
return CastToUIntType(Result, ConvertType(TREE_TYPE(exp)));
}
// Handle floating point comparisons, if we get here.
Value *Result = Builder.CreateFCmp(FCmpInst::Predicate(FPPred),
LHS, RHS, "tmp");
// The GCC type is probably an int, not a bool.
return CastToUIntType(Result, ConvertType(TREE_TYPE(exp)));
}
/// EmitBinOp - 'exp' is a binary operator.
///
Value *TreeToLLVM::EmitBinOp(tree exp, Value *DestLoc, unsigned Opc) {
const Type *Ty = ConvertType(TREE_TYPE(exp));
if (isa<PointerType>(Ty))
return EmitPtrBinOp(exp, Opc); // Pointer arithmetic!
if (isa<StructType>(Ty))
return EmitComplexBinOp(exp, DestLoc);
assert(Ty->isFirstClassType() && DestLoc == 0 &&
"Bad binary operation!");
Value *LHS = Emit(TREE_OPERAND(exp, 0), 0);
Value *RHS = Emit(TREE_OPERAND(exp, 1), 0);
// GCC has no problem with things like "xor uint X, int 17", and X-Y, where
// X and Y are pointer types, but the result is an integer. As such, convert
// everything to the result type.
bool LHSIsSigned = !TYPE_UNSIGNED(TREE_TYPE(TREE_OPERAND(exp, 0)));
bool RHSIsSigned = !TYPE_UNSIGNED(TREE_TYPE(TREE_OPERAND(exp, 1)));
bool TyIsSigned = !TYPE_UNSIGNED(TREE_TYPE(exp));
LHS = CastToAnyType(LHS, LHSIsSigned, Ty, TyIsSigned);
RHS = CastToAnyType(RHS, RHSIsSigned, Ty, TyIsSigned);
return Builder.CreateBinOp((Instruction::BinaryOps)Opc, LHS, RHS, "tmp");
}
/// EmitPtrBinOp - Handle binary expressions involving pointers, e.g. "P+4".
///
Value *TreeToLLVM::EmitPtrBinOp(tree exp, unsigned Opc) {
Value *LHS = Emit(TREE_OPERAND(exp, 0), 0);
// If this is an expression like (P+4), try to turn this into
// "getelementptr P, 1".
if ((Opc == Instruction::Add || Opc == Instruction::Sub) &&
TREE_CODE(TREE_OPERAND(exp, 1)) == INTEGER_CST) {
int64_t Offset = getINTEGER_CSTVal(TREE_OPERAND(exp, 1));
// If POINTER_SIZE is 32-bits, sign extend the offset.
if (POINTER_SIZE == 32)
Offset = (Offset << 32) >> 32;
// Figure out how large the element pointed to is.
const Type *ElTy = cast<PointerType>(LHS->getType())->getElementType();
// We can't get the type size (and thus convert to using a GEP instr) from
// pointers to opaque structs if the type isn't abstract.
if (ElTy->isSized()) {
int64_t EltSize = TD.getTypeSize(ElTy);
// If EltSize exactly divides Offset, then we know that we can turn this
// into a getelementptr instruction.
int64_t EltOffset = EltSize ? Offset/EltSize : 0;
if (EltOffset*EltSize == Offset) {
// If this is a subtract, we want to step backwards.
if (Opc == Instruction::Sub)
EltOffset = -EltOffset;
Constant *C = ConstantInt::get(Type::Int64Ty, EltOffset);
Value *V = Builder.CreateGEP(LHS, C, "tmp");
return CastToType(Instruction::BitCast, V, TREE_TYPE(exp));
}
}
}
Value *RHS = Emit(TREE_OPERAND(exp, 1), 0);
const Type *IntPtrTy = TD.getIntPtrType();
bool LHSIsSigned = !TYPE_UNSIGNED(TREE_TYPE(TREE_OPERAND(exp, 0)));
bool RHSIsSigned = !TYPE_UNSIGNED(TREE_TYPE(TREE_OPERAND(exp, 1)));
LHS = CastToAnyType(LHS, LHSIsSigned, IntPtrTy, false);
RHS = CastToAnyType(RHS, RHSIsSigned, IntPtrTy, false);
Value *V = Builder.CreateBinOp((Instruction::BinaryOps)Opc, LHS, RHS, "tmp");
return CastToType(Instruction::IntToPtr, V, ConvertType(TREE_TYPE(exp)));
}
Value *TreeToLLVM::EmitTruthOp(tree exp, unsigned Opc) {
Value *LHS = Emit(TREE_OPERAND(exp, 0), 0);
Value *RHS = Emit(TREE_OPERAND(exp, 1), 0);
bool LHSIsSigned = !TYPE_UNSIGNED(TREE_TYPE(TREE_OPERAND(exp, 0)));
bool RHSIsSigned = !TYPE_UNSIGNED(TREE_TYPE(TREE_OPERAND(exp, 1)));
// This is a truth operation like the strict &&,||,^^. Convert to bool as
// a test against zero
LHS = Builder.CreateICmpNE(LHS, Constant::getNullValue(LHS->getType()),
"toBool");
RHS = Builder.CreateICmpNE(RHS, Constant::getNullValue(RHS->getType()),
"toBool");
Value *Res = Builder.CreateBinOp((Instruction::BinaryOps)Opc, LHS, RHS,"tmp");
return CastToType(Instruction::ZExt, Res, ConvertType(TREE_TYPE(exp)));
}
Value *TreeToLLVM::EmitShiftOp(tree exp, Value *DestLoc, unsigned Opc) {
assert(DestLoc == 0 && "aggregate shift?");
const Type *Ty = ConvertType(TREE_TYPE(exp));
assert(!isa<PointerType>(Ty) && "Pointer arithmetic!?");
Value *LHS = Emit(TREE_OPERAND(exp, 0), 0);
Value *RHS = Emit(TREE_OPERAND(exp, 1), 0);
if (RHS->getType() != LHS->getType())
RHS = Builder.CreateIntCast(RHS, LHS->getType(), false,
(RHS->getName()+".cast").c_str());
return Builder.CreateBinOp((Instruction::BinaryOps)Opc, LHS, RHS, "tmp");
}
Value *TreeToLLVM::EmitRotateOp(tree exp, unsigned Opc1, unsigned Opc2) {
Value *In = Emit(TREE_OPERAND(exp, 0), 0);
Value *Amt = Emit(TREE_OPERAND(exp, 1), 0);
if (Amt->getType() != In->getType())
Amt = Builder.CreateIntCast(Amt, In->getType(), false,
(Amt->getName()+".cast").c_str());
Value *TypeSize =
ConstantInt::get(In->getType(), In->getType()->getPrimitiveSizeInBits());
// Do the two shifts.
Value *V1 = Builder.CreateBinOp((Instruction::BinaryOps)Opc1, In, Amt, "tmp");
Value *OtherShift = Builder.CreateSub(TypeSize, Amt, "tmp");
Value *V2 = Builder.CreateBinOp((Instruction::BinaryOps)Opc2, In,
OtherShift, "tmp");
// Or the two together to return them.
Value *Merge = Builder.CreateOr(V1, V2, "tmp");
return CastToUIntType(Merge, ConvertType(TREE_TYPE(exp)));
}
Value *TreeToLLVM::EmitMinMaxExpr(tree exp, unsigned UIPred, unsigned SIPred,
unsigned FPPred) {
Value *LHS = Emit(TREE_OPERAND(exp, 0), 0);
Value *RHS = Emit(TREE_OPERAND(exp, 1), 0);
const Type *Ty = ConvertType(TREE_TYPE(exp));
// The LHS, RHS and Ty could be integer, floating or pointer typed. We need
// to convert the LHS and RHS into the destination type before doing the
// comparison. Use CastInst::getCastOpcode to get this right.
bool TyIsSigned = !TYPE_UNSIGNED(TREE_TYPE(exp));
bool LHSIsSigned = !TYPE_UNSIGNED(TREE_TYPE(TREE_OPERAND(exp, 0)));
bool RHSIsSigned = !TYPE_UNSIGNED(TREE_TYPE(TREE_OPERAND(exp, 1)));
Instruction::CastOps opcode =
CastInst::getCastOpcode(LHS, LHSIsSigned, Ty, TyIsSigned);
LHS = CastToType(opcode, LHS, Ty);
opcode = CastInst::getCastOpcode(RHS, RHSIsSigned, Ty, TyIsSigned);
RHS = CastToType(opcode, RHS, Ty);
Value *Compare;
if (LHS->getType()->isFloatingPoint())
Compare = Builder.CreateFCmp(FCmpInst::Predicate(FPPred), LHS, RHS, "tmp");
else if TYPE_UNSIGNED(TREE_TYPE(TREE_OPERAND(exp, 0)))
Compare = Builder.CreateICmp(ICmpInst::Predicate(UIPred), LHS, RHS, "tmp");
else
Compare = Builder.CreateICmp(ICmpInst::Predicate(SIPred), LHS, RHS, "tmp");
return Builder.CreateSelect(Compare, LHS, RHS,
TREE_CODE(exp) == MAX_EXPR ? "max" : "min");
}
Value *TreeToLLVM::EmitEXACT_DIV_EXPR(tree exp, Value *DestLoc) {
// Unsigned EXACT_DIV_EXPR -> normal udiv.
if (TYPE_UNSIGNED(TREE_TYPE(exp)))
return EmitBinOp(exp, DestLoc, Instruction::UDiv);
// If this is a signed EXACT_DIV_EXPR by a constant, and we know that
// the RHS is a multiple of two, we strength reduce the result to use
// a signed SHR here. We have no way in LLVM to represent EXACT_DIV_EXPR
// precisely, so this transform can't currently be performed at the LLVM
// level. This is commonly used for pointer subtraction.
if (TREE_CODE(TREE_OPERAND(exp, 1)) == INTEGER_CST) {
uint64_t IntValue = getINTEGER_CSTVal(TREE_OPERAND(exp, 1));
if (isPowerOf2_64(IntValue)) {
// Create an ashr instruction, by the log of the division amount.
Value *LHS = Emit(TREE_OPERAND(exp, 0), 0);
return Builder.CreateAShr(LHS, ConstantInt::get(LHS->getType(),
Log2_64(IntValue)),"tmp");
}
}
// Otherwise, emit this as a normal signed divide.
return EmitBinOp(exp, DestLoc, Instruction::SDiv);
}
Value *TreeToLLVM::EmitFLOOR_MOD_EXPR(tree exp, Value *DestLoc) {
// Notation: FLOOR_MOD_EXPR <-> Mod, TRUNC_MOD_EXPR <-> Rem.
// We express Mod in terms of Rem as follows: if RHS exactly divides LHS,
// or the values of LHS and RHS have the same sign, then Mod equals Rem.
// Otherwise Mod equals Rem + RHS. This means that LHS Mod RHS traps iff
// LHS Rem RHS traps.
if (TYPE_UNSIGNED(TREE_TYPE(exp)))
// LHS and RHS values must have the same sign if their type is unsigned.
return EmitBinOp(exp, DestLoc, Instruction::URem);
const Type *Ty = ConvertType(TREE_TYPE(exp));
Constant *Zero = ConstantInt::get(Ty, 0);
Value *LHS = Emit(TREE_OPERAND(exp, 0), 0);
Value *RHS = Emit(TREE_OPERAND(exp, 1), 0);
// The two possible values for Mod.
Value *Rem = Builder.CreateSRem(LHS, RHS, "rem");
Value *RemPlusRHS = Builder.CreateAdd(Rem, RHS, "tmp");
// HaveSameSign: (LHS >= 0) == (RHS >= 0).
Value *LHSIsPositive = Builder.CreateICmpSGE(LHS, Zero, "tmp");
Value *RHSIsPositive = Builder.CreateICmpSGE(RHS, Zero, "tmp");
Value *HaveSameSign = Builder.CreateICmpEQ(LHSIsPositive,RHSIsPositive,"tmp");
// RHS exactly divides LHS iff Rem is zero.
Value *RemIsZero = Builder.CreateICmpEQ(Rem, Zero, "tmp");
Value *SameAsRem = Builder.CreateOr(HaveSameSign, RemIsZero, "tmp");
return Builder.CreateSelect(SameAsRem, Rem, RemPlusRHS, "mod");
}
Value *TreeToLLVM::EmitCEIL_DIV_EXPR(tree exp) {
// Notation: CEIL_DIV_EXPR <-> CDiv, TRUNC_DIV_EXPR <-> Div.
// CDiv calculates LHS/RHS by rounding up to the nearest integer. In terms
// of Div this means if the values of LHS and RHS have opposite signs or if
// LHS is zero, then CDiv necessarily equals Div; and
// LHS CDiv RHS = (LHS - Sign(RHS)) Div RHS + 1
// otherwise.
const Type *Ty = ConvertType(TREE_TYPE(exp));
Constant *Zero = ConstantInt::get(Ty, 0);
Constant *One = ConstantInt::get(Ty, 1);
Constant *MinusOne = ConstantInt::getAllOnesValue(Ty);
Value *LHS = Emit(TREE_OPERAND(exp, 0), 0);
Value *RHS = Emit(TREE_OPERAND(exp, 1), 0);
if (!TYPE_UNSIGNED(TREE_TYPE(exp))) {
// In the case of signed arithmetic, we calculate CDiv as follows:
// LHS CDiv RHS = (LHS - Sign(RHS) * Offset) Div RHS + Offset,
// where Offset is 1 if LHS and RHS have the same sign and LHS is
// not zero, and 0 otherwise.
// On some machines INT_MIN Div -1 traps. You might expect a trap for
// INT_MIN CDiv -1 too, but this implementation will not generate one.
// Quick quiz question: what value is returned for INT_MIN CDiv -1?
// Determine the signs of LHS and RHS, and whether they have the same sign.
Value *LHSIsPositive = Builder.CreateICmpSGE(LHS, Zero, "tmp");
Value *RHSIsPositive = Builder.CreateICmpSGE(RHS, Zero, "tmp");
Value *HaveSameSign = Builder.CreateICmpEQ(LHSIsPositive, RHSIsPositive,
"tmp");
// Offset equals 1 if LHS and RHS have the same sign and LHS is not zero.
Value *LHSNotZero = Builder.CreateICmpNE(LHS, Zero, "tmp");
Value *OffsetOne = Builder.CreateAnd(HaveSameSign, LHSNotZero, "tmp");
// ... otherwise it is 0.
Value *Offset = Builder.CreateSelect(OffsetOne, One, Zero, "tmp");
// Calculate Sign(RHS) ...
Value *SignRHS = Builder.CreateSelect(RHSIsPositive, One, MinusOne, "tmp");
// ... and Sign(RHS) * Offset
Value *SignedOffset = CastToType(Instruction::SExt, OffsetOne, Ty);
SignedOffset = Builder.CreateAnd(SignRHS, SignedOffset, "tmp");
// Return CDiv = (LHS - Sign(RHS) * Offset) Div RHS + Offset.
Value *CDiv = Builder.CreateSub(LHS, SignedOffset, "tmp");
CDiv = Builder.CreateSDiv(CDiv, RHS, "tmp");
return Builder.CreateAdd(CDiv, Offset, "cdiv");
}
// In the case of unsigned arithmetic, LHS and RHS necessarily have the
// same sign, so we can use
// LHS CDiv RHS = (LHS - 1) Div RHS + 1
// as long as LHS is non-zero.
// Offset is 1 if LHS is non-zero, 0 otherwise.
Value *LHSNotZero = Builder.CreateICmpNE(LHS, Zero, "tmp");
Value *Offset = Builder.CreateSelect(LHSNotZero, One, Zero, "tmp");
// Return CDiv = (LHS - Offset) Div RHS + Offset.
Value *CDiv = Builder.CreateSub(LHS, Offset, "tmp");
CDiv = Builder.CreateUDiv(CDiv, RHS, "tmp");
return Builder.CreateAdd(CDiv, Offset, "cdiv");
}
Value *TreeToLLVM::EmitROUND_DIV_EXPR(tree exp) {
// Notation: ROUND_DIV_EXPR <-> RDiv, TRUNC_DIV_EXPR <-> Div.
// RDiv calculates LHS/RHS by rounding to the nearest integer. Ties
// are broken by rounding away from zero. In terms of Div this means:
// LHS RDiv RHS = (LHS + (RHS Div 2)) Div RHS
// if the values of LHS and RHS have the same sign; and
// LHS RDiv RHS = (LHS - (RHS Div 2)) Div RHS
// if the values of LHS and RHS differ in sign. The intermediate
// expressions in these formulae can overflow, so some tweaking is
// required to ensure correct results. The details depend on whether
// we are doing signed or unsigned arithmetic.
const Type *Ty = ConvertType(TREE_TYPE(exp));
Constant *Zero = ConstantInt::get(Ty, 0);
Constant *Two = ConstantInt::get(Ty, 2);
Value *LHS = Emit(TREE_OPERAND(exp, 0), 0);
Value *RHS = Emit(TREE_OPERAND(exp, 1), 0);
if (!TYPE_UNSIGNED(TREE_TYPE(exp))) {
// In the case of signed arithmetic, we calculate RDiv as follows:
// LHS RDiv RHS = (sign) ( (|LHS| + (|RHS| UDiv 2)) UDiv |RHS| ),
// where sign is +1 if LHS and RHS have the same sign, -1 if their
// signs differ. Doing the computation unsigned ensures that there
// is no overflow.
// On some machines INT_MIN Div -1 traps. You might expect a trap for
// INT_MIN RDiv -1 too, but this implementation will not generate one.
// Quick quiz question: what value is returned for INT_MIN RDiv -1?
// Determine the signs of LHS and RHS, and whether they have the same sign.
Value *LHSIsPositive = Builder.CreateICmpSGE(LHS, Zero, "tmp");
Value *RHSIsPositive = Builder.CreateICmpSGE(RHS, Zero, "tmp");
Value *HaveSameSign = Builder.CreateICmpEQ(LHSIsPositive, RHSIsPositive,
"tmp");
// Calculate |LHS| ...
Value *MinusLHS = Builder.CreateNeg(LHS, "tmp");
Value *AbsLHS = Builder.CreateSelect(LHSIsPositive, LHS, MinusLHS,
(LHS->getNameStr()+".abs").c_str());
// ... and |RHS|
Value *MinusRHS = Builder.CreateNeg(RHS, "tmp");
Value *AbsRHS = Builder.CreateSelect(RHSIsPositive, RHS, MinusRHS,
(RHS->getNameStr()+".abs").c_str());
// Calculate AbsRDiv = (|LHS| + (|RHS| UDiv 2)) UDiv |RHS|.
Value *HalfAbsRHS = Builder.CreateUDiv(AbsRHS, Two, "tmp");
Value *Numerator = Builder.CreateAdd(AbsLHS, HalfAbsRHS, "tmp");
Value *AbsRDiv = Builder.CreateUDiv(Numerator, AbsRHS, "tmp");
// Return AbsRDiv or -AbsRDiv according to whether LHS and RHS have the
// same sign or not.
Value *MinusAbsRDiv = Builder.CreateNeg(AbsRDiv, "tmp");
return Builder.CreateSelect(HaveSameSign, AbsRDiv, MinusAbsRDiv, "rdiv");
}
// In the case of unsigned arithmetic, LHS and RHS necessarily have the
// same sign, however overflow is a problem. We want to use the formula
// LHS RDiv RHS = (LHS + (RHS Div 2)) Div RHS,
// but if LHS + (RHS Div 2) overflows then we get the wrong result. Since
// the use of a conditional branch seems to be unavoidable, we choose the
// simple solution of explicitly checking for overflow, and using
// LHS RDiv RHS = ((LHS + (RHS Div 2)) - RHS) Div RHS + 1
// if it occurred.
// Usually the numerator is LHS + (RHS Div 2); calculate this.
Value *HalfRHS = Builder.CreateUDiv(RHS, Two, "tmp");
Value *Numerator = Builder.CreateAdd(LHS, HalfRHS, "tmp");
// Did the calculation overflow?
Value *Overflowed = Builder.CreateICmpULT(Numerator, HalfRHS, "tmp");
// If so, use (LHS + (RHS Div 2)) - RHS for the numerator instead.
Value *AltNumerator = Builder.CreateSub(Numerator, RHS, "tmp");
Numerator = Builder.CreateSelect(Overflowed, AltNumerator, Numerator, "tmp");
// Quotient = Numerator / RHS.
Value *Quotient = Builder.CreateUDiv(Numerator, RHS, "tmp");
// Return Quotient unless we overflowed, in which case return Quotient + 1.
return Builder.CreateAdd(Quotient, CastToUIntType(Overflowed, Ty), "rdiv");
}
//===----------------------------------------------------------------------===//
// ... Inline Assembly and Register Variables ...
//===----------------------------------------------------------------------===//
/// Reads from register variables are handled by emitting an inline asm node
/// that copies the value out of the specified register.
Value *TreeToLLVM::EmitReadOfRegisterVariable(tree decl, Value *DestLoc) {
const Type *Ty = ConvertType(TREE_TYPE(decl));
// If there was an error, return something bogus.
if (ValidateRegisterVariable(decl)) {
if (Ty->isFirstClassType())
return UndefValue::get(Ty);
return 0; // Just don't copy something into DestLoc.
}
// Turn this into a 'tmp = call Ty asm "", "={reg}"()'.
FunctionType *FTy = FunctionType::get(Ty, std::vector<const Type*>(),false);
const char *Name = IDENTIFIER_POINTER(DECL_ASSEMBLER_NAME(decl));
InlineAsm *IA = InlineAsm::get(FTy, "", "={"+std::string(Name)+"}", false);
return Builder.CreateCall(IA, "tmp");
}
/// Stores to register variables are handled by emitting an inline asm node
/// that copies the value into the specified register.
void TreeToLLVM::EmitModifyOfRegisterVariable(tree decl, Value *RHS) {
// If there was an error, bail out.
if (ValidateRegisterVariable(decl))
return;
// Turn this into a 'call void asm sideeffect "", "{reg}"(Ty %RHS)'.
std::vector<const Type*> ArgTys;
ArgTys.push_back(ConvertType(TREE_TYPE(decl)));
FunctionType *FTy = FunctionType::get(Type::VoidTy, ArgTys, false);
const char *Name = IDENTIFIER_POINTER(DECL_ASSEMBLER_NAME(decl));
InlineAsm *IA = InlineAsm::get(FTy, "", "{"+std::string(Name)+"}", true);
Builder.CreateCall(IA, RHS);
}
/// ConvertInlineAsmStr - Convert the specified inline asm string to an LLVM
/// InlineAsm string. The GNU style inline asm template string has the
/// following format:
/// %N (for N a digit) means print operand N in usual manner.
/// %= means a unique number for the inline asm.
/// %lN means require operand N to be a CODE_LABEL or LABEL_REF
/// and print the label name with no punctuation.
/// %cN means require operand N to be a constant
/// and print the constant expression with no punctuation.
/// %aN means expect operand N to be a memory address
/// (not a memory reference!) and print a reference to that address.
/// %nN means expect operand N to be a constant and print a constant
/// expression for minus the value of the operand, with no other
/// punctuation.
/// Other %xN expressions are turned into LLVM ${N:x} operands.
///
static std::string ConvertInlineAsmStr(tree exp, unsigned NumOperands) {
static unsigned InlineAsmCounter = 0U;
unsigned InlineAsmNum = InlineAsmCounter++;
tree str = ASM_STRING(exp);
if (TREE_CODE(str) == ADDR_EXPR) str = TREE_OPERAND(str, 0);
// ASM_INPUT_P - This flag is set if this is a non-extended ASM, which means
// that the asm string should not be interpreted, other than to escape $'s.
if (ASM_INPUT_P(exp)) {
const char *InStr = TREE_STRING_POINTER(str);
std::string Result;
while (1) {
switch (*InStr++) {
case 0: return Result; // End of string.
default: Result += InStr[-1]; break; // Normal character.
case '$': Result += "$$"; break; // Escape '$' characters.
}
}
}
// Expand [name] symbolic operand names.
str = resolve_asm_operand_names(str, ASM_OUTPUTS(exp), ASM_INPUTS(exp));
const char *InStr = TREE_STRING_POINTER(str);
std::string Result;
while (1) {
switch (*InStr++) {
case 0: return Result; // End of string.
default: Result += InStr[-1]; break; // Normal character.
case '$': Result += "$$"; break; // Escape '$' characters.
#ifdef ASSEMBLER_DIALECT
// Note that we can't escape to ${, because that is the syntax for vars.
case '{': Result += "$("; break; // Escape '{' character.
case '}': Result += "$)"; break; // Escape '}' character.
case '|': Result += "$|"; break; // Escape '|' character.
#endif
case '%': // GCC escape character.
char EscapedChar = *InStr++;
if (EscapedChar == '%') { // Escaped '%' character
Result += '%';
} else if (EscapedChar == '=') { // Unique ID for the asm instance.
Result += utostr(InlineAsmNum);
} else if (ISALPHA(EscapedChar)) {
// % followed by a letter and some digits. This outputs an operand in a
// special way depending on the letter. We turn this into LLVM ${N:o}
// syntax.
char *EndPtr;
unsigned long OpNum = strtoul(InStr, &EndPtr, 10);
if (InStr == EndPtr) {
error("%Hoperand number missing after %%-letter",&EXPR_LOCATION(exp));
return Result;
} else if (OpNum >= NumOperands) {
error("%Hoperand number out of range", &EXPR_LOCATION(exp));
return Result;
}
Result += "${" + utostr(OpNum) + ":" + EscapedChar + "}";
InStr = EndPtr;
} else if (ISDIGIT(EscapedChar)) {
char *EndPtr;
unsigned long OpNum = strtoul(InStr-1, &EndPtr, 10);
InStr = EndPtr;
Result += "$" + utostr(OpNum);
#ifdef PRINT_OPERAND_PUNCT_VALID_P
} else if (PRINT_OPERAND_PUNCT_VALID_P((unsigned char)EscapedChar)) {
Result += "${:";
Result += EscapedChar;
Result += "}";
#endif
} else {
output_operand_lossage("invalid %%-code");
}
break;
}
}
}
/// CanonicalizeConstraint - If we can canonicalize the constraint into
/// something simpler, do so now. This turns register classes with a single
/// register into the register itself, expands builtin constraints to multiple
/// alternatives, etc.
static std::string CanonicalizeConstraint(const char *Constraint) {
std::string Result;
// Skip over modifier characters.
bool DoneModifiers = false;
while (!DoneModifiers) {
switch (*Constraint) {
default: DoneModifiers = true; break;
case '=': assert(0 && "Should be after '='s");
case '+': assert(0 && "'+' should already be expanded");
case '*':
case '?':
case '!':
++Constraint;
break;
case '&': // Pass earlyclobber to LLVM.
case '%': // Pass commutative to LLVM.
Result += *Constraint++;
break;
case '#': // No constraint letters left.
return Result;
}
}
while (*Constraint) {
char ConstraintChar = *Constraint++;
// 'g' is just short-hand for 'imr'.
if (ConstraintChar == 'g') {
Result += "imr";
continue;
}
// See if this is a regclass constraint.
unsigned RegClass;
if (ConstraintChar == 'r')
// REG_CLASS_FROM_CONSTRAINT doesn't support 'r' for some reason.
RegClass = GENERAL_REGS;
else
RegClass = REG_CLASS_FROM_CONSTRAINT(Constraint[-1], Constraint-1);
if (RegClass == NO_REGS) { // not a reg class.
Result += ConstraintChar;
continue;
}
// Look to see if the specified regclass has exactly one member, and if so,
// what it is. Cache this information in AnalyzedRegClasses once computed.
static std::map<unsigned, int> AnalyzedRegClasses;
std::map<unsigned, int>::iterator I =
AnalyzedRegClasses.lower_bound(RegClass);
int RegMember;
if (I != AnalyzedRegClasses.end() && I->first == RegClass) {
// We've already computed this, reuse value.
RegMember = I->second;
} else {
// Otherwise, scan the regclass, looking for exactly one member.
RegMember = -1; // -1 => not a single-register class.
for (unsigned j = 0; j != FIRST_PSEUDO_REGISTER; ++j)
if (TEST_HARD_REG_BIT(reg_class_contents[RegClass], j)) {
if (RegMember == -1) {
RegMember = j;
} else {
RegMember = -1;
break;
}
}
// Remember this answer for the next query of this regclass.
AnalyzedRegClasses.insert(I, std::make_pair(RegClass, RegMember));
}
// If we found a single register register class, return the register.
if (RegMember != -1) {
Result += '{';
Result += reg_names[RegMember];
Result += '}';
} else {
Result += ConstraintChar;
}
}
return Result;
}
Value *TreeToLLVM::EmitASM_EXPR(tree exp) {
unsigned NumInputs = list_length(ASM_INPUTS(exp));
unsigned NumOutputs = list_length(ASM_OUTPUTS(exp));
unsigned NumInOut = 0;
/// Constraints - The output/input constraints, concatenated together in array
/// form instead of list form.
const char **Constraints =
(const char **)alloca((NumOutputs + NumInputs) * sizeof(const char *));
// FIXME: CHECK ALTERNATIVES, something akin to check_operand_nalternatives.
std::vector<Value*> CallOps;
std::vector<const Type*> CallArgTypes;
std::string NewAsmStr = ConvertInlineAsmStr(exp, NumOutputs+NumInputs);
std::string ConstraintStr;
// StoreCallResultAddr - The pointer to store the result of the call through.
Value *StoreCallResultAddr = 0;
const Type *CallResultType = Type::VoidTy;
// Process outputs.
int ValNum = 0;
for (tree Output = ASM_OUTPUTS(exp); Output;
Output = TREE_CHAIN(Output), ++ValNum) {
tree Operand = TREE_VALUE(Output);
tree type = TREE_TYPE(Operand);
// If there's an erroneous arg, emit no insn.
if (type == error_mark_node) return 0;
// Parse the output constraint.
const char *Constraint =
TREE_STRING_POINTER(TREE_VALUE(TREE_PURPOSE(Output)));
Constraints[ValNum] = Constraint;
bool IsInOut, AllowsReg, AllowsMem;
if (!parse_output_constraint(&Constraint, ValNum, NumInputs, NumOutputs,
&AllowsMem, &AllowsReg, &IsInOut))
return 0;
assert(Constraint[0] == '=' && "Not an output constraint?");
// Output constraints must be addressible if they aren't simple register
// constraints (this emits "address of register var" errors, etc).
if (!AllowsReg && (AllowsMem || IsInOut))
lang_hooks.mark_addressable(Operand);
// Count the number of "+" constraints.
if (IsInOut)
++NumInOut, ++NumInputs;
// If this output register is pinned to a machine register, use that machine
// register instead of the specified constraint.
if (TREE_CODE(Operand) == VAR_DECL && DECL_HARD_REGISTER(Operand)) {
int RegNum =
decode_reg_name(IDENTIFIER_POINTER(DECL_ASSEMBLER_NAME(Operand)));
if (RegNum >= 0) {
unsigned RegNameLen = strlen(reg_names[RegNum]);
char *NewConstraint = (char*)alloca(RegNameLen+4);
NewConstraint[0] = '=';
NewConstraint[1] = '{';
memcpy(NewConstraint+2, reg_names[RegNum], RegNameLen);
NewConstraint[RegNameLen+2] = '}';
NewConstraint[RegNameLen+3] = 0;
Constraint = NewConstraint;
}
}
// If we can simplify the constraint into something else, do so now. This
// avoids LLVM having to know about all the (redundant) GCC constraints.
std::string SimplifiedConstraint = CanonicalizeConstraint(Constraint+1);
LValue Dest = EmitLV(Operand);
const Type *DestValTy =
cast<PointerType>(Dest.Ptr->getType())->getElementType();
assert(!Dest.isBitfield() && "Cannot assign into a bitfield!");
if (ConstraintStr.empty() && !AllowsMem && // Reg dest and no output yet?
DestValTy->isFirstClassType()) {
assert(StoreCallResultAddr == 0 && "Already have a result val?");
StoreCallResultAddr = Dest.Ptr;
ConstraintStr += ",=";
ConstraintStr += SimplifiedConstraint;
CallResultType = DestValTy;
} else {
ConstraintStr += ",=*";
ConstraintStr += SimplifiedConstraint;
CallOps.push_back(Dest.Ptr);
CallArgTypes.push_back(Dest.Ptr->getType());
}
}
// Process inputs.
for (tree Input = ASM_INPUTS(exp); Input; Input = TREE_CHAIN(Input),++ValNum){
tree Val = TREE_VALUE(Input);
tree type = TREE_TYPE(Val);
// If there's an erroneous arg, emit no insn.
if (type == error_mark_node) return 0;
const char *Constraint =
TREE_STRING_POINTER(TREE_VALUE(TREE_PURPOSE(Input)));
Constraints[ValNum] = Constraint;
bool AllowsReg, AllowsMem;
if (!parse_input_constraint(Constraints+ValNum, ValNum-NumOutputs,
NumInputs, NumOutputs, NumInOut,
Constraints, &AllowsMem, &AllowsReg))
return 0;
bool isIndirect = false;
if (AllowsReg || !AllowsMem) { // Register operand.
const Type *LLVMTy = ConvertType(type);
Value *Op = 0;
if (LLVMTy->isFirstClassType()) {
Op = Emit(Val, 0);
} else {
LValue LV = EmitLV(Val);
assert(!LV.isBitfield() && "Inline asm can't have bitfield operand");
// Structs and unions are permitted here, as long as they're the
// same size as a register.
uint64_t TySize = TD.getTypeSizeInBits(LLVMTy);
if (TySize == 1 || TySize == 8 || TySize == 16 ||
TySize == 32 || TySize == 64) {
LLVMTy = IntegerType::get(TySize);
Op = Builder.CreateLoad(CastToType(Instruction::BitCast, LV.Ptr,
PointerType::get(LLVMTy)), "tmp");
} else {
// Otherwise, emit our value as a lvalue and let the codegen deal with
// it.
isIndirect = true;
Op = LV.Ptr;
}
}
CallOps.push_back(Op);
CallArgTypes.push_back(Op->getType());
} else { // Memory operand.
lang_hooks.mark_addressable(TREE_VALUE(Input));
isIndirect = true;
LValue Src = EmitLV(Val);
assert(!Src.isBitfield() && "Cannot read from a bitfield!");
CallOps.push_back(Src.Ptr);
CallArgTypes.push_back(Src.Ptr->getType());
}
ConstraintStr += ',';
if (isIndirect)
ConstraintStr += '*';
// If this output register is pinned to a machine register, use that machine
// register instead of the specified constraint.
int RegNum;
if (TREE_CODE(Val) == VAR_DECL && DECL_HARD_REGISTER(Val) &&
(RegNum =
decode_reg_name(IDENTIFIER_POINTER(DECL_ASSEMBLER_NAME(Val)))) >= 0) {
ConstraintStr += '{';
ConstraintStr += reg_names[RegNum];
ConstraintStr += '}';
} else {
// If there is a simpler form for the register constraint, use it.
std::string Simplified = CanonicalizeConstraint(Constraint);
ConstraintStr += Simplified;
}
}
if (ASM_USES(exp)) {
// FIXME: Figure out what ASM_USES means.
error("%Hcode warrior/ms asm not supported yet in %qs", &EXPR_LOCATION(exp),
TREE_STRING_POINTER(ASM_STRING(exp)));
return 0;
}
// Process clobbers.
// Some targets automatically clobber registers across an asm.
tree Clobbers = targetm.md_asm_clobbers(ASM_CLOBBERS(exp));
for (; Clobbers; Clobbers = TREE_CHAIN(Clobbers)) {
const char *RegName = TREE_STRING_POINTER(TREE_VALUE(Clobbers));
int RegCode = decode_reg_name(RegName);
switch (RegCode) {
case -1: // Nothing specified?
case -2: // Invalid.
error("%Hunknown register name %qs in %<asm%>", &EXPR_LOCATION(exp),
RegName);
return 0;
case -3: // cc
ConstraintStr += ",~{cc}";
break;
case -4: // memory
ConstraintStr += ",~{memory}";
break;
default: // Normal register name.
ConstraintStr += ",~{";
ConstraintStr += reg_names[RegCode];
ConstraintStr += "}";
break;
}
}
const FunctionType *FTy =
FunctionType::get(CallResultType, CallArgTypes, false);
// Remove the leading comma if we have operands.
if (!ConstraintStr.empty())
ConstraintStr.erase(ConstraintStr.begin());
// Make sure we're created a valid inline asm expression.
if (!InlineAsm::Verify(FTy, ConstraintStr)) {
error("%HInvalid or unsupported inline assembly!", &EXPR_LOCATION(exp));
return 0;
}
Value *Asm = InlineAsm::get(FTy, NewAsmStr, ConstraintStr,
ASM_VOLATILE_P(exp) || !ASM_OUTPUTS(exp));
CallInst *CV = Builder.CreateCall(Asm, CallOps.begin(), CallOps.end(),
StoreCallResultAddr ? "tmp" : "");
// If the call produces a value, store it into the destination.
if (StoreCallResultAddr)
Builder.CreateStore(CV, StoreCallResultAddr);
// Give the backend a chance to upgrade the inline asm to LLVM code. This
// handles some common cases that LLVM has intrinsics for, e.g. x86 bswap ->
// llvm.bswap.
if (const TargetAsmInfo *TAI = TheTarget->getTargetAsmInfo())
TAI->ExpandInlineAsm(CV);
return 0;
}
//===----------------------------------------------------------------------===//
// ... Helpers for Builtin Function Expansion ...
//===----------------------------------------------------------------------===//
Value *TreeToLLVM::BuildVector(const std::vector<Value*> &Ops) {
assert((Ops.size() & (Ops.size()-1)) == 0 &&
"Not a power-of-two sized vector!");
bool AllConstants = true;
for (unsigned i = 0, e = Ops.size(); i != e && AllConstants; ++i)
AllConstants &= isa<Constant>(Ops[i]);
// If this is a constant vector, create a ConstantVector.
if (AllConstants) {
std::vector<Constant*> CstOps;
for (unsigned i = 0, e = Ops.size(); i != e; ++i)
CstOps.push_back(cast<Constant>(Ops[i]));
return ConstantVector::get(CstOps);
}
// Otherwise, insertelement the values to build the vector.
Value *Result =
UndefValue::get(VectorType::get(Ops[0]->getType(), Ops.size()));
for (unsigned i = 0, e = Ops.size(); i != e; ++i)
Result = Builder.CreateInsertElement(Result, Ops[i],
ConstantInt::get(Type::Int32Ty, i),
"tmp");
return Result;
}
/// BuildVector - This varargs function builds a literal vector ({} syntax) with
/// the specified null-terminated list of elements. The elements must be all
/// the same element type and there must be a power of two of them.
Value *TreeToLLVM::BuildVector(Value *Elt, ...) {
std::vector<Value*> Ops;
va_list VA;
va_start(VA, Elt);
Ops.push_back(Elt);
while (Value *Arg = va_arg(VA, Value *))
Ops.push_back(Arg);
va_end(VA);
return BuildVector(Ops);
}
/// BuildVectorShuffle - Given two vectors and a variable length list of int
/// constants, create a shuffle of the elements of the inputs, where each dest
/// is specified by the indexes. The int constant list must be as long as the
/// number of elements in the input vector.
///
/// Undef values may be specified by passing in -1 as the result value.
///
Value *TreeToLLVM::BuildVectorShuffle(Value *InVec1, Value *InVec2, ...) {
assert(isa<VectorType>(InVec1->getType()) &&
InVec1->getType() == InVec2->getType() && "Invalid shuffle!");
unsigned NumElements = cast<VectorType>(InVec1->getType())->getNumElements();
// Get all the indexes from varargs.
std::vector<Constant*> Idxs;
va_list VA;
va_start(VA, InVec2);
for (unsigned i = 0; i != NumElements; ++i) {
int idx = va_arg(VA, int);
if (idx == -1)
Idxs.push_back(UndefValue::get(Type::Int32Ty));
else {
assert((unsigned)idx < 2*NumElements && "Element index out of range!");
Idxs.push_back(ConstantInt::get(Type::Int32Ty, idx));
}
}
va_end(VA);
// Turn this into the appropriate shuffle operation.
return Builder.CreateShuffleVector(InVec1, InVec2, ConstantVector::get(Idxs),
"tmp");
}
//===----------------------------------------------------------------------===//
// ... Builtin Function Expansion ...
//===----------------------------------------------------------------------===//
/// EmitFrontendExpandedBuiltinCall - For MD builtins that do not have a
/// directly corresponding LLVM intrinsic, we allow the target to do some amount
/// of lowering. This allows us to avoid having intrinsics for operations that
/// directly correspond to LLVM constructs.
///
/// This method returns true if the builtin is handled, otherwise false.
///
bool TreeToLLVM::EmitFrontendExpandedBuiltinCall(tree exp, tree fndecl,
Value *DestLoc,Value *&Result){
#ifdef LLVM_TARGET_INTRINSIC_LOWER
// Get the result type and oeprand line in an easy to consume format.
const Type *ResultType = ConvertType(TREE_TYPE(TREE_TYPE(fndecl)));
std::vector<Value*> Operands;
for (tree Op = TREE_OPERAND(exp, 1); Op; Op = TREE_CHAIN(Op))
Operands.push_back(Emit(TREE_VALUE(Op), 0));
unsigned FnCode = DECL_FUNCTION_CODE(fndecl);
return LLVM_TARGET_INTRINSIC_LOWER(exp, FnCode, DestLoc, Result, ResultType,
Operands);
#endif
return false;
}
/// TargetBuiltinCache - A cache of builtin intrisics indexed by the GCC builtin
/// number.
static std::vector<Constant*> TargetBuiltinCache;
void clearTargetBuiltinCache() {
TargetBuiltinCache.clear();
}
/// EmitBuiltinCall - exp is a call to fndecl, a builtin function. Try to emit
/// the call in a special way, setting Result to the scalar result if necessary.
/// If we can't handle the builtin, return false, otherwise return true.
bool TreeToLLVM::EmitBuiltinCall(tree exp, tree fndecl,
Value *DestLoc, Value *&Result) {
if (DECL_BUILT_IN_CLASS(fndecl) == BUILT_IN_MD) {
unsigned FnCode = DECL_FUNCTION_CODE(fndecl);
if (TargetBuiltinCache.size() <= FnCode)
TargetBuiltinCache.resize(FnCode+1);
// If we haven't converted this intrinsic over yet, do so now.
if (TargetBuiltinCache[FnCode] == 0) {
const char *TargetPrefix = "";
#ifdef LLVM_TARGET_INTRINSIC_PREFIX
TargetPrefix = LLVM_TARGET_INTRINSIC_PREFIX;
#endif
// If this builtin directly corresponds to an LLVM intrinsic, get the
// IntrinsicID now.
const char *BuiltinName = IDENTIFIER_POINTER(DECL_NAME(fndecl));
Intrinsic::ID IntrinsicID;
#define GET_LLVM_INTRINSIC_FOR_GCC_BUILTIN
#include "llvm/Intrinsics.gen"
#undef GET_LLVM_INTRINSIC_FOR_GCC_BUILTIN
if (IntrinsicID == Intrinsic::not_intrinsic) {
if (EmitFrontendExpandedBuiltinCall(exp, fndecl, DestLoc, Result))
return true;
std::cerr << "TYPE: " << *ConvertType(TREE_TYPE(fndecl)) << "\n";
error("%Hunsupported target builtin %<%s%> used", &EXPR_LOCATION(exp),
BuiltinName);
const Type *ResTy = ConvertType(TREE_TYPE(exp));
if (ResTy->isFirstClassType())
Result = UndefValue::get(ResTy);
return true;
}
// Finally, map the intrinsic ID back to a name.
TargetBuiltinCache[FnCode] =
Intrinsic::getDeclaration(TheModule, IntrinsicID);
}
Result = EmitCallOf(TargetBuiltinCache[FnCode], exp, DestLoc);
return true;
}
switch (DECL_FUNCTION_CODE(fndecl)) {
default: return false;
// Varargs builtins.
case BUILT_IN_VA_START:
case BUILT_IN_STDARG_START: return EmitBuiltinVAStart(exp);
case BUILT_IN_VA_END: return EmitBuiltinVAEnd(exp);
case BUILT_IN_VA_COPY: return EmitBuiltinVACopy(exp);
case BUILT_IN_CONSTANT_P: return EmitBuiltinConstantP(exp, Result);
case BUILT_IN_ALLOCA: return EmitBuiltinAlloca(exp, Result);
case BUILT_IN_EXTEND_POINTER: return EmitBuiltinExtendPointer(exp, Result);
case BUILT_IN_EXPECT: return EmitBuiltinExpect(exp, DestLoc, Result);
case BUILT_IN_MEMCPY: return EmitBuiltinMemCopy(exp, Result, false);
case BUILT_IN_MEMMOVE: return EmitBuiltinMemCopy(exp, Result, true);
case BUILT_IN_MEMSET: return EmitBuiltinMemSet(exp, Result);
case BUILT_IN_BZERO: return EmitBuiltinBZero(exp, Result);
case BUILT_IN_PREFETCH: return EmitBuiltinPrefetch(exp);
case BUILT_IN_FRAME_ADDRESS: return EmitBuiltinReturnAddr(exp, Result,true);
case BUILT_IN_RETURN_ADDRESS: return EmitBuiltinReturnAddr(exp, Result,false);
case BUILT_IN_STACK_SAVE: return EmitBuiltinStackSave(exp, Result);
case BUILT_IN_STACK_RESTORE: return EmitBuiltinStackRestore(exp);
case BUILT_IN_EXTRACT_RETURN_ADDR:
return EmitBuiltinExtractReturnAddr(exp, Result);
case BUILT_IN_FROB_RETURN_ADDR:
return EmitBuiltinFrobReturnAddr(exp, Result);
case BUILT_IN_INIT_TRAMPOLINE:
return EmitBuiltinInitTrampoline(exp, Result);
// Builtins used by the exception handling runtime.
case BUILT_IN_DWARF_CFA:
return EmitBuiltinDwarfCFA(exp, Result);
#ifdef DWARF2_UNWIND_INFO
case BUILT_IN_DWARF_SP_COLUMN:
return EmitBuiltinDwarfSPColumn(exp, Result);
case BUILT_IN_INIT_DWARF_REG_SIZES:
return EmitBuiltinInitDwarfRegSizes(exp, Result);
#endif
case BUILT_IN_EH_RETURN:
return EmitBuiltinEHReturn(exp, Result);
#ifdef EH_RETURN_DATA_REGNO
case BUILT_IN_EH_RETURN_DATA_REGNO:
return EmitBuiltinEHReturnDataRegno(exp, Result);
#endif
case BUILT_IN_UNWIND_INIT:
return EmitBuiltinUnwindInit(exp, Result);
#define HANDLE_UNARY_FP(F32, F64, V) \
Result = EmitBuiltinUnaryFPOp(V, Intrinsic::F32, Intrinsic::F64)
// Unary bit counting intrinsics.
// NOTE: do not merge these case statements. That will cause the memoized
// Function* to be incorrectly shared across the different typed functions.
case BUILT_IN_CLZ: // These GCC builtins always return int.
case BUILT_IN_CLZL:
case BUILT_IN_CLZLL: {
Value *Amt = Emit(TREE_VALUE(TREE_OPERAND(exp, 1)), 0);
EmitBuiltinUnaryIntOp(Amt, Result, Intrinsic::ctlz);
const Type *DestTy = ConvertType(TREE_TYPE(exp));
if (Result->getType() != DestTy)
Result = Builder.CreateIntCast(Result, DestTy, "cast");
return true;
}
case BUILT_IN_CTZ: // These GCC builtins always return int.
case BUILT_IN_CTZL:
case BUILT_IN_CTZLL: {
Value *Amt = Emit(TREE_VALUE(TREE_OPERAND(exp, 1)), 0);
EmitBuiltinUnaryIntOp(Amt, Result, Intrinsic::cttz);
const Type *DestTy = ConvertType(TREE_TYPE(exp));
if (Result->getType() != DestTy)
Result = Builder.CreateIntCast(Result, DestTy, "cast");
return true;
}
case BUILT_IN_POPCOUNT: // These GCC builtins always return int.
case BUILT_IN_POPCOUNTL:
case BUILT_IN_POPCOUNTLL: {
Value *Amt = Emit(TREE_VALUE(TREE_OPERAND(exp, 1)), 0);
EmitBuiltinUnaryIntOp(Amt, Result, Intrinsic::ctpop);
const Type *DestTy = ConvertType(TREE_TYPE(exp));
if (Result->getType() != DestTy)
Result = Builder.CreateIntCast(Result, DestTy, "cast");
return true;
}
case BUILT_IN_SQRT:
case BUILT_IN_SQRTF:
case BUILT_IN_SQRTL:
// If errno math has been disabled, expand these to llvm.sqrt calls.
if (!flag_errno_math) {
Value *Amt = Emit(TREE_VALUE(TREE_OPERAND(exp, 1)), 0);
HANDLE_UNARY_FP(sqrt_f32, sqrt_f64, Amt);
Result = CastToFPType(Result, ConvertType(TREE_TYPE(exp)));
return true;
}
break;
case BUILT_IN_POWI:
case BUILT_IN_POWIF:
case BUILT_IN_POWIL:
Result = EmitBuiltinPOWI(exp);
return true;
case BUILT_IN_FFS: // These GCC builtins always return int.
case BUILT_IN_FFSL:
case BUILT_IN_FFSLL: { // FFS(X) -> (x == 0 ? 0 : CTTZ(x)+1)
// The argument and return type of cttz should match the argument type of
// the ffs, but should ignore the return type of ffs.
Value *Amt = Emit(TREE_VALUE(TREE_OPERAND(exp, 1)), 0);
EmitBuiltinUnaryIntOp(Amt, Result, Intrinsic::cttz);
Result = Builder.CreateAdd(Result, ConstantInt::get(Result->getType(), 1),
"tmp");
Value *Cond =
Builder.CreateICmpEQ(Amt, Constant::getNullValue(Amt->getType()), "tmp");
Result = Builder.CreateSelect(Cond,
Constant::getNullValue(Result->getType()),
Result, "tmp");
return true;
}
#undef HANDLE_UNARY_FP
#if 1 // FIXME: Should handle these GCC extensions eventually.
case BUILT_IN_APPLY_ARGS:
case BUILT_IN_APPLY:
case BUILT_IN_RETURN:
case BUILT_IN_SAVEREGS:
case BUILT_IN_ARGS_INFO:
case BUILT_IN_NEXT_ARG:
case BUILT_IN_CLASSIFY_TYPE:
case BUILT_IN_AGGREGATE_INCOMING_ADDRESS:
case BUILT_IN_SETJMP:
case BUILT_IN_LONGJMP:
case BUILT_IN_UPDATE_SETJMP_BUF:
case BUILT_IN_TRAP:
// FIXME: HACK: Just ignore these.
{
const Type *Ty = ConvertType(TREE_TYPE(exp));
if (Ty != Type::VoidTy)
Result = Constant::getNullValue(Ty);
return true;
}
#endif // FIXME: Should handle these GCC extensions eventually.
}
return false;
}
bool TreeToLLVM::EmitBuiltinUnaryIntOp(Value *InVal, Value *&Result,
Intrinsic::ID Id) {
// The intrinsic might be overloaded in which case the argument is of
// varying type. Make sure that we specify the actual type for "iAny"
// by passing it as the 3rd and 4th parameters. This isn't needed for
// most intrinsics, but is needed for ctpop, cttz, ctlz.
const Type *Ty = InVal->getType();
Result = Builder.CreateCall(Intrinsic::getDeclaration(TheModule, Id, &Ty, 1),
InVal, "tmp");
return true;
}
Value *TreeToLLVM::EmitBuiltinUnaryFPOp(Value *Amt, const char *F32Name,
const char *F64Name) {
const char *Name = 0;
switch (Amt->getType()->getTypeID()) {
default: assert(0 && "Unknown FP type!");
case Type::FloatTyID: Name = F32Name; break;
case Type::DoubleTyID: Name = F64Name; break;
}
return Builder.CreateCall(cast<Function>(
TheModule->getOrInsertFunction(Name, Amt->getType(), Amt->getType(), NULL)),
Amt, "tmp");
}
Value *TreeToLLVM::EmitBuiltinUnaryFPOp(Value *Amt,
Intrinsic::ID F32ID,
Intrinsic::ID F64ID) {
Intrinsic::ID Id = Intrinsic::not_intrinsic;
switch (Amt->getType()->getTypeID()) {
default: assert(0 && "Unknown FP type!");
case Type::FloatTyID: Id = F32ID; break;
case Type::DoubleTyID: Id = F64ID; break;
}
return Builder.CreateCall(Intrinsic::getDeclaration(TheModule, Id),
Amt, "tmp");
}
Value *TreeToLLVM::EmitBuiltinPOWI(tree exp) {
tree ArgList = TREE_OPERAND (exp, 1);
if (!validate_arglist(ArgList, REAL_TYPE, INTEGER_TYPE, VOID_TYPE))
return 0;
Value *Val = Emit(TREE_VALUE(ArgList), 0);
Value *Pow = Emit(TREE_VALUE(TREE_CHAIN(ArgList)), 0);
Pow = CastToSIntType(Pow, Type::Int32Ty);
Intrinsic::ID Id = Intrinsic::not_intrinsic;
switch (Val->getType()->getTypeID()) {
default: assert(0 && "Unknown FP type!");
case Type::FloatTyID: Id = Intrinsic::powi_f32; break;
case Type::DoubleTyID: Id = Intrinsic::powi_f64; break;
}
SmallVector<Value *,2> Args;
Args.push_back(Val);
Args.push_back(Pow);
return Builder.CreateCall(Intrinsic::getDeclaration(TheModule, Id),
Args.begin(), Args.end(), "tmp");
}
bool TreeToLLVM::EmitBuiltinConstantP(tree exp, Value *&Result) {
Result = Constant::getNullValue(ConvertType(TREE_TYPE(exp)));
return true;
}
bool TreeToLLVM::EmitBuiltinExtendPointer(tree exp, Value *&Result) {
tree arglist = TREE_OPERAND(exp, 1);
Value *Amt = Emit(TREE_VALUE(arglist), 0);
bool AmtIsSigned = !TYPE_UNSIGNED(TREE_TYPE(TREE_VALUE(arglist)));
bool ExpIsSigned = !TYPE_UNSIGNED(TREE_TYPE(exp));
Result = CastToAnyType(Amt, AmtIsSigned, ConvertType(TREE_TYPE(exp)),
ExpIsSigned);
return true;
}
/// EmitBuiltinMemCopy - Emit an llvm.memcpy or llvm.memmove intrinsic,
/// depending on the value of isMemMove.
bool TreeToLLVM::EmitBuiltinMemCopy(tree_node *exp, Value *&Result,
bool isMemMove) {
tree arglist = TREE_OPERAND(exp, 1);
if (!validate_arglist(arglist, POINTER_TYPE, POINTER_TYPE,
INTEGER_TYPE, VOID_TYPE))
return false;
tree Dst = TREE_VALUE(arglist);
tree Src = TREE_VALUE(TREE_CHAIN(arglist));
unsigned SrcAlign = get_pointer_alignment(Src, BIGGEST_ALIGNMENT);
unsigned DstAlign = get_pointer_alignment(Dst, BIGGEST_ALIGNMENT);
// If the DST or SRC pointers are not pointer type, do this out of line.
if (SrcAlign == 0 || DstAlign == 0) return false;
Value *DstV = Emit(Dst, 0);
Value *SrcV = Emit(Src, 0);
Value *Len = Emit(TREE_VALUE(TREE_CHAIN(TREE_CHAIN(arglist))), 0);
if (isMemMove)
EmitMemMove(DstV, SrcV, Len, std::min(SrcAlign, DstAlign)/8);
else
EmitMemCpy(DstV, SrcV, Len, std::min(SrcAlign, DstAlign)/8);
Result = DstV;
return true;
}
bool TreeToLLVM::EmitBuiltinMemSet(tree_node *exp, Value *&Result) {
tree arglist = TREE_OPERAND(exp, 1);
if (!validate_arglist(arglist, POINTER_TYPE, INTEGER_TYPE,
INTEGER_TYPE, VOID_TYPE))
return false;
tree Dst = TREE_VALUE(arglist);
unsigned DstAlign = get_pointer_alignment(Dst, BIGGEST_ALIGNMENT);
// If the DST pointer is not a pointer type, do this out of line.
if (DstAlign == 0) return false;
Value *DstV = Emit(Dst, 0);
Value *Val = Emit(TREE_VALUE(TREE_CHAIN(arglist)), 0);
Value *Len = Emit(TREE_VALUE(TREE_CHAIN(TREE_CHAIN(arglist))), 0);
EmitMemSet(DstV, Val, Len, DstAlign/8);
Result = DstV;
return true;
}
bool TreeToLLVM::EmitBuiltinBZero(tree_node *exp, Value *&Result) {
tree arglist = TREE_OPERAND(exp, 1);
if (!validate_arglist(arglist, POINTER_TYPE, INTEGER_TYPE, VOID_TYPE))
return false;
tree Dst = TREE_VALUE(arglist);
unsigned DstAlign = get_pointer_alignment(Dst, BIGGEST_ALIGNMENT);
// If the DST pointer is not a pointer type, do this out of line.
if (DstAlign == 0) return false;
Value *DstV = Emit(Dst, 0);
Value *Val = Constant::getNullValue(Type::Int32Ty);
Value *Len = Emit(TREE_VALUE(TREE_CHAIN(arglist)), 0);
EmitMemSet(DstV, Val, Len, DstAlign/8);
return true;
}
bool TreeToLLVM::EmitBuiltinPrefetch(tree exp) {
tree arglist = TREE_OPERAND(exp, 1);
if (!validate_arglist(arglist, POINTER_TYPE, 0))
return false;
Value *Ptr = Emit(TREE_VALUE(arglist), 0);
Value *ReadWrite = 0;
Value *Locality = 0;
if (TREE_CHAIN(arglist)) { // Args 1/2 are optional
ReadWrite = Emit(TREE_VALUE(TREE_CHAIN(arglist)), 0);
if (!isa<ConstantInt>(ReadWrite)) {
error("second argument to %<__builtin_prefetch%> must be a constant");
ReadWrite = 0;
} else if (cast<ConstantInt>(ReadWrite)->getZExtValue() > 1) {
warning ("invalid second argument to %<__builtin_prefetch%>;"
" using zero");
ReadWrite = 0;
} else {
ReadWrite = ConstantExpr::getIntegerCast(cast<Constant>(ReadWrite),
Type::Int32Ty, false);
}
if (TREE_CHAIN(TREE_CHAIN(arglist))) {
Locality = Emit(TREE_VALUE(TREE_CHAIN(TREE_CHAIN(arglist))), 0);
if (!isa<ConstantInt>(Locality)) {
error("third argument to %<__builtin_prefetch%> must be a constant");
Locality = 0;
} else if (cast<ConstantInt>(Locality)->getZExtValue() > 3) {
warning("invalid third argument to %<__builtin_prefetch%>; using 3");
Locality = 0;
} else {
Locality = ConstantExpr::getIntegerCast(cast<Constant>(Locality),
Type::Int32Ty, false);
}
}
}
// Default to highly local read.
if (ReadWrite == 0)
ReadWrite = Constant::getNullValue(Type::Int32Ty);
if (Locality == 0)
Locality = ConstantInt::get(Type::Int32Ty, 3);
Ptr = CastToType(Instruction::BitCast, Ptr, PointerType::get(Type::Int8Ty));
Value *Ops[3] = { Ptr, ReadWrite, Locality };
Builder.CreateCall(Intrinsic::getDeclaration(TheModule, Intrinsic::prefetch),
Ops, Ops+3);
return true;
}
/// EmitBuiltinReturnAddr - Emit an llvm.returnaddress or llvm.frameaddress
/// instruction, depending on whether isFrame is true or not.
bool TreeToLLVM::EmitBuiltinReturnAddr(tree exp, Value *&Result, bool isFrame) {
tree arglist = TREE_OPERAND(exp, 1);
if (!validate_arglist(arglist, INTEGER_TYPE, VOID_TYPE))
return false;
ConstantInt *Level = dyn_cast<ConstantInt>(Emit(TREE_VALUE(arglist), 0));
if (!Level) {
if (isFrame)
error("invalid argument to %<__builtin_frame_address%>");
else
error("invalid argument to %<__builtin_return_address%>");
return false;
}
Intrinsic::ID IID =
!isFrame ? Intrinsic::returnaddress : Intrinsic::frameaddress;
Result = Builder.CreateCall(Intrinsic::getDeclaration(TheModule, IID),
Level, "tmp");
Result = CastToType(Instruction::BitCast, Result, TREE_TYPE(exp));
return true;
}
bool TreeToLLVM::EmitBuiltinExtractReturnAddr(tree exp, Value *&Result) {
tree arglist = TREE_OPERAND(exp, 1);
Value *Ptr = Emit(TREE_VALUE(arglist), 0);
// FIXME: Actually we should do something like this:
//
// Result = (Ptr & MASK_RETURN_ADDR) + RETURN_ADDR_OFFSET, if mask and
// offset are defined. This seems to be needed for: ARM, MIPS, Sparc.
// Unfortunately, these constants are defined as RTL expressions and
// should be handled separately.
Result = CastToType(Instruction::BitCast, Ptr, PointerType::get(Type::Int8Ty));
return true;
}
bool TreeToLLVM::EmitBuiltinFrobReturnAddr(tree exp, Value *&Result) {
tree arglist = TREE_OPERAND(exp, 1);
Value *Ptr = Emit(TREE_VALUE(arglist), 0);
// FIXME: Actually we should do something like this:
//
// Result = Ptr - RETURN_ADDR_OFFSET, if offset is defined. This seems to be
// needed for: MIPS, Sparc. Unfortunately, these constants are defined
// as RTL expressions and should be handled separately.
Result = CastToType(Instruction::BitCast, Ptr, PointerType::get(Type::Int8Ty));
return true;
}
bool TreeToLLVM::EmitBuiltinStackSave(tree exp, Value *&Result) {
tree arglist = TREE_OPERAND(exp, 1);
if (!validate_arglist(arglist, VOID_TYPE))
return false;
Result = Builder.CreateCall(Intrinsic::getDeclaration(TheModule,
Intrinsic::stacksave),
"tmp");
return true;
}
// Builtins used by the exception handling runtime.
// On most machines, the CFA coincides with the first incoming parm.
#ifndef ARG_POINTER_CFA_OFFSET
#define ARG_POINTER_CFA_OFFSET(FNDECL) FIRST_PARM_OFFSET (FNDECL)
#endif
// The mapping from gcc register number to DWARF 2 CFA column number. By
// default, we just provide columns for all registers.
#ifndef DWARF_FRAME_REGNUM
#define DWARF_FRAME_REGNUM(REG) DBX_REGISTER_NUMBER (REG)
#endif
// Map register numbers held in the call frame info that gcc has
// collected using DWARF_FRAME_REGNUM to those that should be output in
// .debug_frame and .eh_frame.
#ifndef DWARF2_FRAME_REG_OUT
#define DWARF2_FRAME_REG_OUT(REGNO, FOR_EH) (REGNO)
#endif
/* Registers that get partially clobbered by a call in a given mode.
These must not be call used registers. */
#ifndef HARD_REGNO_CALL_PART_CLOBBERED
#define HARD_REGNO_CALL_PART_CLOBBERED(REGNO, MODE) 0
#endif
bool TreeToLLVM::EmitBuiltinDwarfCFA(tree exp, Value *&Result) {
if (!validate_arglist(TREE_OPERAND(exp, 1), VOID_TYPE))
return false;
int cfa_offset = ARG_POINTER_CFA_OFFSET(0);
Result = Builder.CreateCall(Intrinsic::getDeclaration(TheModule,
Intrinsic::eh_dwarf_cfa),
ConstantInt::get(Type::Int32Ty, cfa_offset));
return true;
}
bool TreeToLLVM::EmitBuiltinDwarfSPColumn(tree exp, Value *&Result) {
if (!validate_arglist(TREE_OPERAND(exp, 1), VOID_TYPE))
return false;
unsigned int dwarf_regnum = DWARF_FRAME_REGNUM(STACK_POINTER_REGNUM);
Result = ConstantInt::get(ConvertType(TREE_TYPE(exp)), dwarf_regnum);
return true;
}
bool TreeToLLVM::EmitBuiltinEHReturnDataRegno(tree exp, Value *&Result) {
tree arglist = TREE_OPERAND(exp, 1);
if (!validate_arglist(arglist, INTEGER_TYPE, VOID_TYPE))
return false;
tree which = TREE_VALUE (arglist);
unsigned HOST_WIDE_INT iwhich;
if (TREE_CODE (which) != INTEGER_CST) {
error ("argument of %<__builtin_eh_return_regno%> must be constant");
return false;
}
iwhich = tree_low_cst (which, 1);
iwhich = EH_RETURN_DATA_REGNO (iwhich);
if (iwhich == INVALID_REGNUM)
return false;
iwhich = DWARF_FRAME_REGNUM (iwhich);
Result = ConstantInt::get(ConvertType(TREE_TYPE(exp)), iwhich);
return true;
}
bool TreeToLLVM::EmitBuiltinEHReturn(tree exp, Value *&Result) {
tree arglist = TREE_OPERAND(exp, 1);
if (!validate_arglist(arglist, INTEGER_TYPE, POINTER_TYPE, VOID_TYPE))
return false;
Value *Offset = Emit(TREE_VALUE(arglist), 0);
Value *Handler = Emit(TREE_VALUE(TREE_CHAIN(arglist)), 0);
Offset = Builder.CreateIntCast(Offset, Type::Int32Ty, true, "tmp");
Handler = CastToType(Instruction::BitCast, Handler,
PointerType::get(Type::Int8Ty));
SmallVector<Value *, 2> Args;
Args.push_back(Offset);
Args.push_back(Handler);
Builder.CreateCall(Intrinsic::getDeclaration(TheModule,
Intrinsic::eh_return),
Args.begin(), Args.end());
Result = Builder.CreateUnreachable();
EmitBlock(new BasicBlock(""));
return true;
}
bool TreeToLLVM::EmitBuiltinInitDwarfRegSizes(tree exp, Value *&Result) {
unsigned int i;
bool wrote_return_column = false;
static bool reg_modes_initialized = false;
tree arglist = TREE_OPERAND(exp, 1);
if (!validate_arglist(arglist, POINTER_TYPE, VOID_TYPE))
return false;
if (!reg_modes_initialized) {
init_reg_modes_once();
reg_modes_initialized = true;
}
Value *Addr = BitCastToType(Emit(TREE_VALUE(arglist), 0),
PointerType::get(Type::Int8Ty));
Constant *Size, *Idx;
for (i = 0; i < FIRST_PSEUDO_REGISTER; i++) {
int rnum = DWARF2_FRAME_REG_OUT (DWARF_FRAME_REGNUM (i), 1);
if (rnum < DWARF_FRAME_REGISTERS) {
enum machine_mode save_mode = reg_raw_mode[i];
HOST_WIDE_INT size;
if (HARD_REGNO_CALL_PART_CLOBBERED (i, save_mode))
save_mode = choose_hard_reg_mode (i, 1, true);
if (DWARF_FRAME_REGNUM (i) == DWARF_FRAME_RETURN_COLUMN) {
if (save_mode == VOIDmode)
continue;
wrote_return_column = true;
}
size = GET_MODE_SIZE (save_mode);
if (rnum < 0)
continue;
Size = ConstantInt::get(Type::Int8Ty, size);
Idx = ConstantInt::get(Type::Int32Ty, rnum);
Builder.CreateStore(Size, Builder.CreateGEP(Addr, Idx, "tmp"), false);
}
}
if (!wrote_return_column) {
Size = ConstantInt::get(Type::Int8Ty, GET_MODE_SIZE (Pmode));
Idx = ConstantInt::get(Type::Int32Ty, DWARF_FRAME_RETURN_COLUMN);
Builder.CreateStore(Size, Builder.CreateGEP(Addr, Idx, "tmp"), false);
}
#ifdef DWARF_ALT_FRAME_RETURN_COLUMN
Size = ConstantInt::get(Type::Int8Ty, GET_MODE_SIZE (Pmode));
Idx = ConstantInt::get(Type::Int32Ty, DWARF_ALT_FRAME_RETURN_COLUMN);
Builder.CreateStore(Size, Builder.CreateGEP(Addr, Idx, "tmp"), false);
#endif
// TODO: the RS6000 target needs extra initialization [gcc changeset 122468].
return true;
}
bool TreeToLLVM::EmitBuiltinUnwindInit(tree exp, Value *&Result) {
if (!validate_arglist(TREE_OPERAND(exp, 1), VOID_TYPE))
return false;
Result = Builder.CreateCall(Intrinsic::getDeclaration(TheModule,
Intrinsic::eh_unwind_init));
return true;
}
bool TreeToLLVM::EmitBuiltinStackRestore(tree exp) {
tree arglist = TREE_OPERAND(exp, 1);
if (!validate_arglist(arglist, POINTER_TYPE, VOID_TYPE))
return false;
Value *Ptr = Emit(TREE_VALUE(arglist), 0);
Ptr = CastToType(Instruction::BitCast, Ptr, PointerType::get(Type::Int8Ty));
Builder.CreateCall(Intrinsic::getDeclaration(TheModule,
Intrinsic::stackrestore), Ptr);
return true;
}
bool TreeToLLVM::EmitBuiltinAlloca(tree exp, Value *&Result) {
tree arglist = TREE_OPERAND(exp, 1);
if (!validate_arglist(arglist, INTEGER_TYPE, VOID_TYPE))
return false;
Value *Amt = Emit(TREE_VALUE(arglist), 0);
Amt = CastToSIntType(Amt, Type::Int32Ty);
Result = Builder.CreateAlloca(Type::Int8Ty, Amt, "tmp");
return true;
}
bool TreeToLLVM::EmitBuiltinExpect(tree exp, Value *DestLoc, Value *&Result) {
// Ignore the hint for now, just expand the expr. This is safe, but not
// optimal.
tree arglist = TREE_OPERAND(exp, 1);
if (arglist == NULL_TREE || TREE_CHAIN(arglist) == NULL_TREE)
return true;
Result = Emit(TREE_VALUE(arglist), DestLoc);
return true;
}
bool TreeToLLVM::EmitBuiltinVAStart(tree exp) {
tree arglist = TREE_OPERAND(exp, 1);
tree fntype = TREE_TYPE(current_function_decl);
if (TYPE_ARG_TYPES(fntype) == 0 ||
(TREE_VALUE(tree_last(TYPE_ARG_TYPES(fntype))) == void_type_node)) {
error("`va_start' used in function with fixed args");
return true;
}
tree last_parm = tree_last(DECL_ARGUMENTS(current_function_decl));
tree chain = TREE_CHAIN(arglist);
// Check for errors.
if (fold_builtin_next_arg (chain))
return true;
tree arg = TREE_VALUE(chain);
Value *ArgVal = Emit(TREE_VALUE(arglist), 0);
Constant *llvm_va_start_fn = Intrinsic::getDeclaration(TheModule,
Intrinsic::vastart);
const Type *FTy =
cast<PointerType>(llvm_va_start_fn->getType())->getElementType();
ArgVal = CastToType(Instruction::BitCast, ArgVal,
PointerType::get(Type::Int8Ty));
Builder.CreateCall(llvm_va_start_fn, ArgVal);
return true;
}
bool TreeToLLVM::EmitBuiltinVAEnd(tree exp) {
Value *Arg = Emit(TREE_VALUE(TREE_OPERAND(exp, 1)), 0);
Arg = CastToType(Instruction::BitCast, Arg,
PointerType::get(Type::Int8Ty));
Builder.CreateCall(Intrinsic::getDeclaration(TheModule, Intrinsic::vaend),
Arg);
return true;
}
bool TreeToLLVM::EmitBuiltinVACopy(tree exp) {
tree Arg1T = TREE_VALUE(TREE_OPERAND(exp, 1));
tree Arg2T = TREE_VALUE(TREE_CHAIN(TREE_OPERAND(exp, 1)));
Value *Arg1 = Emit(Arg1T, 0); // Emit the address of the destination.
// The second arg of llvm.va_copy is a pointer to a valist.
Value *Arg2;
if (!isAggregateTreeType(TREE_TYPE(Arg2T))) {
// Emit it as a value, then store it to a temporary slot.
Value *V2 = Emit(Arg2T, 0);
Arg2 = CreateTemporary(V2->getType());
Builder.CreateStore(V2, Arg2);
} else {
// If the target has aggregate valists, emit the srcval directly into a
// temporary.
const Type *VAListTy = cast<PointerType>(Arg1->getType())->getElementType();
Arg2 = CreateTemporary(VAListTy);
Emit(Arg2T, Arg2);
}
static const Type *VPTy = PointerType::get(Type::Int8Ty);
SmallVector<Value *, 2> Args;
Args.push_back(CastToType(Instruction::BitCast, Arg1, VPTy));
Args.push_back(CastToType(Instruction::BitCast, Arg2, VPTy));
Builder.CreateCall(Intrinsic::getDeclaration(TheModule, Intrinsic::vacopy),
Args.begin(), Args.end());
return true;
}
bool TreeToLLVM::EmitBuiltinInitTrampoline(tree exp, Value *&Result) {
tree arglist = TREE_OPERAND(exp, 1);
if (!validate_arglist (arglist, POINTER_TYPE, POINTER_TYPE, POINTER_TYPE,
VOID_TYPE))
return false;
static const Type *VPTy = PointerType::get(Type::Int8Ty);
Value *Tramp = Emit(TREE_VALUE(arglist), 0);
Tramp = CastToType(Instruction::BitCast, Tramp, VPTy);
Value *Func = Emit(TREE_VALUE(TREE_CHAIN(arglist)), 0);
Func = CastToType(Instruction::BitCast, Func, VPTy);
Value *Chain = Emit(TREE_VALUE(TREE_CHAIN(TREE_CHAIN(arglist))), 0);
Chain = CastToType(Instruction::BitCast, Chain, VPTy);
Value *Ops[3] = { Tramp, Func, Chain };
Function *Intr = Intrinsic::getDeclaration(TheModule,
Intrinsic::init_trampoline);
Result = Builder.CreateCall(Intr, Ops, Ops+3, "tramp");
return true;
}
//===----------------------------------------------------------------------===//
// ... Complex Math Expressions ...
//===----------------------------------------------------------------------===//
void TreeToLLVM::EmitLoadFromComplex(Value *&Real, Value *&Imag,
Value *SrcComplex, bool isVolatile) {
Value *I0 = ConstantInt::get(Type::Int32Ty, 0);
Value *I1 = ConstantInt::get(Type::Int32Ty, 1);
Value *Idxs[2] = { I0, I0 };
Value *RealPtr = Builder.CreateGEP(SrcComplex, Idxs, Idxs + 2, "real");
Real = Builder.CreateLoad(RealPtr, isVolatile, "real");
Idxs[1] = I1;
Value *ImagPtr = Builder.CreateGEP(SrcComplex, Idxs, Idxs + 2, "real");
Imag = Builder.CreateLoad(ImagPtr, isVolatile, "imag");
}
void TreeToLLVM::EmitStoreToComplex(Value *DestComplex, Value *Real,
Value *Imag, bool isVolatile) {
Value *I0 = ConstantInt::get(Type::Int32Ty, 0);
Value *I1 = ConstantInt::get(Type::Int32Ty, 1);
Value *Idxs[2] = { I0, I0 };
Value *RealPtr = Builder.CreateGEP(DestComplex, Idxs, Idxs + 2, "real");
Builder.CreateStore(Real, RealPtr, isVolatile);
Idxs[1] = I1;
Value *ImagPtr = Builder.CreateGEP(DestComplex, Idxs, Idxs + 2, "real");
Builder.CreateStore(Imag, ImagPtr, isVolatile);
}
void TreeToLLVM::EmitCOMPLEX_EXPR(tree exp, Value *DestLoc) {
Value *Real = Emit(TREE_OPERAND(exp, 0), 0);
Value *Imag = Emit(TREE_OPERAND(exp, 1), 0);
EmitStoreToComplex(DestLoc, Real, Imag, false);
}
void TreeToLLVM::EmitCOMPLEX_CST(tree exp, Value *DestLoc) {
Value *Real = Emit(TREE_REALPART(exp), 0);
Value *Imag = Emit(TREE_IMAGPART(exp), 0);
EmitStoreToComplex(DestLoc, Real, Imag, false);
}
// EmitComplexBinOp - Note that this operands on binops like ==/!=, which return
// a bool, not a complex value.
Value *TreeToLLVM::EmitComplexBinOp(tree exp, Value *DestLoc) {
const Type *ComplexTy = ConvertType(TREE_TYPE(TREE_OPERAND(exp, 0)));
Value *LHSTmp = CreateTemporary(ComplexTy);
Value *RHSTmp = CreateTemporary(ComplexTy);
Emit(TREE_OPERAND(exp, 0), LHSTmp);
Emit(TREE_OPERAND(exp, 1), RHSTmp);
Value *LHSr, *LHSi;
EmitLoadFromComplex(LHSr, LHSi, LHSTmp,
TREE_THIS_VOLATILE(TREE_OPERAND(exp, 0)));
Value *RHSr, *RHSi;
EmitLoadFromComplex(RHSr, RHSi, RHSTmp,
TREE_THIS_VOLATILE(TREE_OPERAND(exp, 1)));
Value *DSTr, *DSTi;
switch (TREE_CODE(exp)) {
default: TODO(exp);
case PLUS_EXPR: // (a+ib) + (c+id) = (a+c) + i(b+d)
DSTr = Builder.CreateAdd(LHSr, RHSr, "tmpr");
DSTi = Builder.CreateAdd(LHSi, RHSi, "tmpi");
break;
case MINUS_EXPR: // (a+ib) - (c+id) = (a-c) + i(b-d)
DSTr = Builder.CreateSub(LHSr, RHSr, "tmpr");
DSTi = Builder.CreateSub(LHSi, RHSi, "tmpi");
break;
case MULT_EXPR: { // (a+ib) * (c+id) = (ac-bd) + i(ad+cb)
Value *Tmp1 = Builder.CreateMul(LHSr, RHSr, "tmp"); // a*c
Value *Tmp2 = Builder.CreateMul(LHSi, RHSi, "tmp"); // b*d
DSTr = Builder.CreateSub(Tmp1, Tmp2, "tmp"); // ac-bd
Value *Tmp3 = Builder.CreateMul(LHSr, RHSi, "tmp"); // a*d
Value *Tmp4 = Builder.CreateMul(RHSr, LHSi, "tmp"); // c*b
DSTi = Builder.CreateAdd(Tmp3, Tmp4, "tmp"); // ad+cb
break;
}
case RDIV_EXPR: { // (a+ib) / (c+id) = ((ac+bd)/(cc+dd)) + i((bc-ad)/(cc+dd))
Value *Tmp1 = Builder.CreateMul(LHSr, RHSr, "tmp"); // a*c
Value *Tmp2 = Builder.CreateMul(LHSi, RHSi, "tmp"); // b*d
Value *Tmp3 = Builder.CreateAdd(Tmp1, Tmp2, "tmp"); // ac+bd
Value *Tmp4 = Builder.CreateMul(RHSr, RHSr, "tmp"); // c*c
Value *Tmp5 = Builder.CreateMul(RHSi, RHSi, "tmp"); // d*d
Value *Tmp6 = Builder.CreateAdd(Tmp4, Tmp5, "tmp"); // cc+dd
// FIXME: What about integer complex?
DSTr = Builder.CreateFDiv(Tmp3, Tmp6, "tmp");
Value *Tmp7 = Builder.CreateMul(LHSi, RHSr, "tmp"); // b*c
Value *Tmp8 = Builder.CreateMul(LHSr, RHSi, "tmp"); // a*d
Value *Tmp9 = Builder.CreateSub(Tmp7, Tmp8, "tmp"); // bc-ad
DSTi = Builder.CreateFDiv(Tmp9, Tmp6, "tmp");
break;
}
case EQ_EXPR: // (a+ib) == (c+id) = (a == c) & (b == d)
// FIXME: What about integer complex?
DSTr = Builder.CreateFCmpOEQ(LHSr, RHSr, "tmpr");
DSTi = Builder.CreateFCmpOEQ(LHSi, RHSi, "tmpi");
return Builder.CreateAnd(DSTr, DSTi, "tmp");
case NE_EXPR: // (a+ib) != (c+id) = (a != c) | (b != d)
// FIXME: What about integer complex?
DSTr = Builder.CreateFCmpUNE(LHSr, RHSr, "tmpr");
DSTi = Builder.CreateFCmpUNE(LHSi, RHSi, "tmpi");
return Builder.CreateOr(DSTr, DSTi, "tmp");
}
EmitStoreToComplex(DestLoc, DSTr, DSTi, false);
return 0;
}
//===----------------------------------------------------------------------===//
// ... L-Value Expressions ...
//===----------------------------------------------------------------------===//
LValue TreeToLLVM::EmitLV_DECL(tree exp) {
if (TREE_CODE(exp) == PARM_DECL || TREE_CODE(exp) == VAR_DECL ||
TREE_CODE(exp) == CONST_DECL) {
// If a static var's type was incomplete when the decl was written,
// but the type is complete now, lay out the decl now.
if (DECL_SIZE(exp) == 0 && COMPLETE_OR_UNBOUND_ARRAY_TYPE_P(TREE_TYPE(exp))
&& (TREE_STATIC(exp) || DECL_EXTERNAL(exp))) {
layout_decl(exp, 0);
// This mirrors code in layout_decl for munging the RTL. Here we actually
// emit a NEW declaration for the global variable, now that it has been
// laid out. We then tell the compiler to "forward" any uses of the old
// global to this new one.
if (Value *Val = DECL_LLVM_IF_SET(exp)) {
//fprintf(stderr, "***\n*** SHOULD HANDLE GLOBAL VARIABLES!\n***\n");
//assert(0 && "Reimplement this with replace all uses!");
#if 0
SET_DECL_LLVM(exp, 0);
// Create a new global variable declaration
llvm_assemble_external(exp);
V2GV(Val)->ForwardedGlobal = V2GV(DECL_LLVM(exp));
#endif
}
}
}
assert(!isGCC_SSA_Temporary(exp) &&
"Cannot use an SSA temporary as an l-value");
Value *Decl = DECL_LLVM(exp);
if (Decl == 0) {
if (errorcount || sorrycount) {
const PointerType *Ty = PointerType::get(ConvertType(TREE_TYPE(exp)));
return ConstantPointerNull::get(Ty);
}
assert(0 && "INTERNAL ERROR: Referencing decl that hasn't been laid out");
abort();
}
// Ensure variable marked as used even if it doesn't go through a parser. If
// it hasn't been used yet, write out an external definition.
if (!TREE_USED(exp)) {
assemble_external(exp);
TREE_USED(exp) = 1;
Decl = DECL_LLVM(exp);
}
if (GlobalValue *GV = dyn_cast<GlobalValue>(Decl)) {
// If this is an aggregate CONST_DECL, emit it to LLVM now. GCC happens to
// get this case right by forcing the initializer into memory.
if (TREE_CODE(exp) == CONST_DECL) {
if (DECL_INITIAL(exp) && GV->isDeclaration()) {
emit_global_to_llvm(exp);
Decl = DECL_LLVM(exp); // Decl could have change if it changed type.
}
} else {
// Otherwise, inform cgraph that we used the global.
mark_decl_referenced(exp);
if (tree ID = DECL_ASSEMBLER_NAME(exp))
mark_referenced(ID);
}
}
const Type *Ty = ConvertType(TREE_TYPE(exp));
// If we have "extern void foo", make the global have type {} instead of
// type void.
if (Ty == Type::VoidTy) Ty = StructType::get(std::vector<const Type*>(),
false);
const PointerType *PTy = PointerType::get(Ty);
return CastToType(Instruction::BitCast, Decl, PTy);
}
LValue TreeToLLVM::EmitLV_ARRAY_REF(tree exp) {
// The result type is an ElementTy* in the case of an ARRAY_REF, an array
// of ElementTy in the case of ARRAY_RANGE_REF.
tree Array = TREE_OPERAND(exp, 0);
tree ArrayType = TREE_TYPE(Array);
tree Index = TREE_OPERAND(exp, 1);
tree IndexType = TREE_TYPE(Index);
tree ElementType = TREE_TYPE(ArrayType);
assert((TREE_CODE (ArrayType) == ARRAY_TYPE ||
TREE_CODE (ArrayType) == POINTER_TYPE ||
TREE_CODE (ArrayType) == REFERENCE_TYPE) &&
"Unknown ARRAY_REF!");
// As an LLVM extension, we allow ARRAY_REF with a pointer as the first
// operand. This construct maps directly to a getelementptr instruction.
Value *ArrayAddr;
if (TREE_CODE(ArrayType) == ARRAY_TYPE) {
// First subtract the lower bound, if any, in the type of the index.
tree LowerBound = array_ref_low_bound(exp);
if (!integer_zerop(LowerBound))
Index = fold(build2(MINUS_EXPR, IndexType, Index, LowerBound));
LValue ArrayAddrLV = EmitLV(Array);
assert(!ArrayAddrLV.isBitfield() && "Arrays cannot be bitfields!");
ArrayAddr = ArrayAddrLV.Ptr;
} else {
ArrayAddr = Emit(Array, 0);
}
Value *IndexVal = Emit(Index, 0);
const Type *IntPtrTy = getTargetData().getIntPtrType();
if (TYPE_UNSIGNED(IndexType)) // if the index is unsigned
// ZExt it to retain its value in the larger type
IndexVal = CastToUIntType(IndexVal, IntPtrTy);
else
// SExt it to retain its value in the larger type
IndexVal = CastToSIntType(IndexVal, IntPtrTy);
// If this is an index into an LLVM array, codegen as a GEP.
if (isArrayCompatible(ArrayType)) {
Value *Idxs[2] = { ConstantInt::get(Type::Int32Ty, 0), IndexVal };
Value *Ptr = Builder.CreateGEP(ArrayAddr, Idxs, Idxs + 2, "tmp");
return BitCastToType(Ptr, PointerType::get(ConvertType(TREE_TYPE(exp))));
}
// If we are indexing over a fixed-size type, just use a GEP.
if (isSequentialCompatible(ArrayType)) {
const Type *PtrElementTy = PointerType::get(ConvertType(ElementType));
ArrayAddr = BitCastToType(ArrayAddr, PtrElementTy);
Value *Ptr = Builder.CreateGEP(ArrayAddr, IndexVal, "tmp");
return BitCastToType(Ptr, PointerType::get(ConvertType(TREE_TYPE(exp))));
}
// Otherwise, just do raw, low-level pointer arithmetic. FIXME: this could be
// much nicer in cases like:
// float foo(int w, float A[][w], int g) { return A[g][0]; }
ArrayAddr = BitCastToType(ArrayAddr, PointerType::get(Type::Int8Ty));
Value *TypeSize = Emit(array_ref_element_size(exp), 0);
TypeSize = CastToUIntType(TypeSize, IntPtrTy);
IndexVal = Builder.CreateMul(IndexVal, TypeSize, "tmp");
Value *Ptr = Builder.CreateGEP(ArrayAddr, IndexVal, "tmp");
return BitCastToType(Ptr, PointerType::get(ConvertType(TREE_TYPE(exp))));
}
/// getFieldOffsetInBits - Return the offset (in bits) of a FIELD_DECL in a
/// structure.
static unsigned getFieldOffsetInBits(tree Field) {
assert(DECL_FIELD_BIT_OFFSET(Field) != 0 && DECL_FIELD_OFFSET(Field) != 0);
unsigned Result = TREE_INT_CST_LOW(DECL_FIELD_BIT_OFFSET(Field));
if (TREE_CODE(DECL_FIELD_OFFSET(Field)) == INTEGER_CST)
Result += TREE_INT_CST_LOW(DECL_FIELD_OFFSET(Field))*8;
return Result;
}
/// getComponentRefOffsetInBits - Return the offset (in bits) of the field
/// referenced in a COMPONENT_REF exp.
static unsigned getComponentRefOffsetInBits(tree exp) {
assert(TREE_CODE(exp) == COMPONENT_REF && "not a COMPONENT_REF!");
tree field = TREE_OPERAND(exp, 1);
assert(TREE_CODE(field) == FIELD_DECL && "not a FIELD_DECL!");
tree field_offset = component_ref_field_offset (exp);
assert(DECL_FIELD_BIT_OFFSET(field) && field_offset);
unsigned Result = TREE_INT_CST_LOW(DECL_FIELD_BIT_OFFSET(field));
if (TREE_CODE(field_offset) == INTEGER_CST)
Result += TREE_INT_CST_LOW(field_offset)*8;
return Result;
}
LValue TreeToLLVM::EmitLV_COMPONENT_REF(tree exp) {
LValue StructAddrLV = EmitLV(TREE_OPERAND(exp, 0));
tree FieldDecl = TREE_OPERAND(exp, 1);
assert((TREE_CODE(DECL_CONTEXT(FieldDecl)) == RECORD_TYPE ||
TREE_CODE(DECL_CONTEXT(FieldDecl)) == UNION_TYPE));
// Ensure that the struct type has been converted, so that the fielddecls
// are laid out. Note that we convert to the context of the Field, not to the
// type of Operand #0, because GCC doesn't always have the field match up with
// operand #0's type.
const Type *StructTy = ConvertType(DECL_CONTEXT(FieldDecl));
assert((!StructAddrLV.isBitfield() ||
StructAddrLV.BitStart == 0) && "structs cannot be bitfields!");
StructAddrLV.Ptr = CastToType(Instruction::BitCast, StructAddrLV.Ptr,
PointerType::get(StructTy));
const Type *FieldTy = ConvertType(TREE_TYPE(FieldDecl));
// BitStart - This is the actual offset of the field from the start of the
// struct, in bits. For bitfields this may be on a non-byte boundary.
unsigned BitStart = getComponentRefOffsetInBits(exp);
Value *FieldPtr;
tree field_offset = component_ref_field_offset (exp);
// If this is a normal field at a fixed offset from the start, handle it.
if (TREE_CODE(field_offset) == INTEGER_CST) {
assert(DECL_LLVM_SET_P(FieldDecl) && "Struct not laid out for LLVM?");
ConstantInt *CI = cast<ConstantInt>(DECL_LLVM(FieldDecl));
uint32_t MemberIndex = CI->getZExtValue();
assert(MemberIndex < StructTy->getNumContainedTypes() &&
"Field Idx out of range!");
Value *Idxs[2] = { Constant::getNullValue(Type::Int32Ty), CI };
FieldPtr = Builder.CreateGEP(StructAddrLV.Ptr, Idxs, Idxs + 2, "tmp");
// Now that we did an offset from the start of the struct, subtract off
// the offset from BitStart.
if (MemberIndex) {
const StructLayout *SL = TD.getStructLayout(cast<StructType>(StructTy));
BitStart -= SL->getElementOffset(MemberIndex) * 8;
}
} else {
Value *Offset = Emit(field_offset, 0);
Value *Ptr = CastToType(Instruction::PtrToInt, StructAddrLV.Ptr,
Offset->getType());
Ptr = Builder.CreateAdd(Ptr, Offset, "tmp");
FieldPtr = CastToType(Instruction::IntToPtr, Ptr,PointerType::get(FieldTy));
}
if (tree DeclaredType = DECL_BIT_FIELD_TYPE(FieldDecl)) {
const Type *LLVMFieldTy =
cast<PointerType>(FieldPtr->getType())->getElementType();
// If this is a bitfield, the declared type must be an integral type.
FieldTy = ConvertType(DeclaredType);
// If the field result is a bool, cast to a ubyte instead. It is not
// possible to access all bits of a memory object with a bool (only the low
// bit) but it is possible to access them with a byte.
if (FieldTy == Type::Int1Ty)
FieldTy = Type::Int8Ty;
assert(FieldTy->isInteger() && "Invalid bitfield");
// If the LLVM notion of the field type is larger than the actual field type
// being accessed, use the LLVM type. This avoids pointer casts and other
// bad things that are difficult to clean up later. This occurs in cases
// like "struct X{ unsigned long long x:50; unsigned y:2; }" when accessing
// y. We want to access the field as a ulong, not as a uint with an offset.
if (LLVMFieldTy->isInteger() &&
LLVMFieldTy->getPrimitiveSizeInBits() >
FieldTy->getPrimitiveSizeInBits())
FieldTy = LLVMFieldTy;
// We are now loading/storing through a casted pointer type, whose
// signedness depends on the signedness of the field. Force the field to
// be unsigned. This solves performance problems where you have, for
// example: struct { int A:1; unsigned B:2; }; Consider a store to A then
// a store to B. In this case, without this conversion, you'd have a
// store through an int*, followed by a load from a uint*. Forcing them
// both to uint* allows the store to be forwarded to the load.
// If this is a bitfield, the field may span multiple fields in the LLVM
// type. As such, cast the pointer to be a pointer to the declared type.
FieldPtr = CastToType(Instruction::BitCast, FieldPtr,
PointerType::get(FieldTy));
// If this is a normal bitfield reference, return it as such.
if (DECL_SIZE(FieldDecl) && TREE_CODE(DECL_SIZE(FieldDecl)) == INTEGER_CST){
unsigned LLVMValueBitSize = FieldTy->getPrimitiveSizeInBits();
unsigned BitfieldSize = TREE_INT_CST_LOW(DECL_SIZE(FieldDecl));
// Finally, because bitfields can span LLVM fields, and because the start
// of the first LLVM field (where FieldPtr currently points) may be up to
// 63 bits away from the start of the bitfield), it is possible that
// *FieldPtr doesn't contain all of the bits for this bitfield. If needed,
// adjust FieldPtr so that it is close enough to the bitfield that
// *FieldPtr contains all of the needed bits. Be careful to make sure
// that the pointer remains appropriately aligned.
if (BitStart+BitfieldSize > LLVMValueBitSize) {
// In this case, we know that the alignment of the field is less than
// the size of the field. To get the pointer close enough, add some
// number of alignment units to the pointer.
unsigned ByteAlignment = TD.getABITypeAlignment(FieldTy);
// It is possible that an individual field is Packed. This information is
// not reflected in FieldTy. Check DECL_PACKED here.
if (DECL_PACKED(FieldDecl))
ByteAlignment = 1;
assert(ByteAlignment*8 <= LLVMValueBitSize && "Unknown overlap case!");
unsigned NumAlignmentUnits = BitStart/(ByteAlignment*8);
assert(NumAlignmentUnits && "Not adjusting pointer?");
// Compute the byte offset, and add it to the pointer.
unsigned ByteOffset = NumAlignmentUnits*ByteAlignment;
Constant *Offset = ConstantInt::get(TD.getIntPtrType(), ByteOffset);
FieldPtr = CastToType(Instruction::PtrToInt, FieldPtr,
Offset->getType());
FieldPtr = Builder.CreateAdd(FieldPtr, Offset, "tmp");
FieldPtr = CastToType(Instruction::IntToPtr, FieldPtr,
PointerType::get(FieldTy));
// Adjust bitstart to account for the pointer movement.
BitStart -= ByteOffset*8;
// Check that this worked.
assert(BitStart < LLVMValueBitSize &&
BitStart+BitfieldSize <= LLVMValueBitSize &&
"Couldn't get bitfield into value!");
}
// Okay, everything is good. Return this as a bitfield if we can't
// return it as a normal l-value. (e.g. "struct X { int X : 32 };" ).
if (BitfieldSize != LLVMValueBitSize || BitStart != 0)
return LValue(FieldPtr, BitStart, BitfieldSize);
}
} else {
// Make sure we return a pointer to the right type.
FieldPtr = CastToType(Instruction::BitCast, FieldPtr,
PointerType::get(ConvertType(TREE_TYPE(exp))));
}
assert(BitStart == 0 &&
"It's a bitfield reference or we didn't get to the field!");
return LValue(FieldPtr);
}
LValue TreeToLLVM::EmitLV_BIT_FIELD_REF(tree exp) {
LValue Ptr = EmitLV(TREE_OPERAND(exp, 0));
assert(!Ptr.isBitfield() && "BIT_FIELD_REF operands cannot be bitfields!");
unsigned BitStart = (unsigned)TREE_INT_CST_LOW(TREE_OPERAND(exp, 2));
unsigned BitSize = (unsigned)TREE_INT_CST_LOW(TREE_OPERAND(exp, 1));
const Type *ValTy = ConvertType(TREE_TYPE(exp));
unsigned ValueSizeInBits = 8*TD.getTypeSize(ValTy);
assert(BitSize <= ValueSizeInBits &&
"ValTy isn't large enough to hold the value loaded!");
// BIT_FIELD_REF values can have BitStart values that are quite large. We
// know that the thing we are loading is ValueSizeInBits large. If BitStart
// is larger than ValueSizeInBits, bump the pointer over to where it should
// be.
if (unsigned UnitOffset = BitStart / ValueSizeInBits) {
// TODO: If Ptr.Ptr is a struct type or something, we can do much better
// than this. e.g. check out when compiling unwind-dw2-fde-darwin.c.
Ptr.Ptr = CastToType(Instruction::BitCast, Ptr.Ptr,
PointerType::get(ValTy));
Ptr.Ptr = Builder.CreateGEP(Ptr.Ptr,
ConstantInt::get(Type::Int32Ty, UnitOffset),
"tmp");
BitStart -= UnitOffset*ValueSizeInBits;
}
// If this is referring to the whole field, return the whole thing.
if (BitStart == 0 && BitSize == ValueSizeInBits)
return LValue(BitCastToType(Ptr.Ptr, PointerType::get(ValTy)));
return LValue(BitCastToType(Ptr.Ptr, PointerType::get(ValTy)), BitStart,
BitSize);
}
LValue TreeToLLVM::EmitLV_XXXXPART_EXPR(tree exp, unsigned Idx) {
LValue Ptr = EmitLV(TREE_OPERAND(exp, 0));
assert(!Ptr.isBitfield() && "BIT_FIELD_REF operands cannot be bitfields!");
Value *Idxs[2] = { ConstantInt::get(Type::Int32Ty, 0),
ConstantInt::get(Type::Int32Ty, Idx) };
return LValue(Builder.CreateGEP(Ptr.Ptr, Idxs, Idxs + 2, "tmp"));
}
LValue TreeToLLVM::EmitLV_VIEW_CONVERT_EXPR(tree exp) {
// The address is the address of the operand.
LValue LV = EmitLV(TREE_OPERAND(exp, 0));
// The type is the type of the expression.
const Type *Ty = ConvertType(TREE_TYPE(exp));
LV.Ptr = BitCastToType(LV.Ptr, PointerType::get(Ty));
return LV;
}
//===----------------------------------------------------------------------===//
// ... Constant Expressions ...
//===----------------------------------------------------------------------===//
/// EmitCONSTRUCTOR - emit the constructor into the location specified by
/// DestLoc.
Value *TreeToLLVM::EmitCONSTRUCTOR(tree exp, Value *DestLoc) {
tree type = TREE_TYPE(exp);
const Type *Ty = ConvertType(type);
if (const VectorType *PTy = dyn_cast<VectorType>(Ty)) {
assert(DestLoc == 0 && "Dest location for packed value?");
std::vector<Value *> BuildVecOps;
// Insert zero initializers for any uninitialized values.
Constant *Zero = Constant::getNullValue(PTy->getElementType());
BuildVecOps.resize(cast<VectorType>(Ty)->getNumElements(), Zero);
// Insert all of the elements here.
for (tree Ops = TREE_OPERAND(exp, 0); Ops; Ops = TREE_CHAIN(Ops)) {
if (!TREE_PURPOSE(Ops)) continue; // Not actually initialized?
unsigned FieldNo = TREE_INT_CST_LOW(TREE_PURPOSE(Ops));
// Update the element.
if (FieldNo < BuildVecOps.size())
BuildVecOps[FieldNo] = Emit(TREE_VALUE(Ops), 0);
}
return BuildVector(BuildVecOps);
}
assert(!Ty->isFirstClassType() && "Constructor for scalar type??");
// Start out with the value zero'd out.
EmitAggregateZero(DestLoc, type);
tree elt = CONSTRUCTOR_ELTS(exp);
switch (TREE_CODE(TREE_TYPE(exp))) {
case ARRAY_TYPE:
case RECORD_TYPE:
default:
if (elt) {
// We don't handle elements yet.
TODO(exp);
}
return 0;
case UNION_TYPE:
// Store each element of the constructor into the corresponding field of
// DEST.
if (elt == NULL_TREE) return 0; // no elements
assert(TREE_CHAIN(elt) == 0 &&"Union CONSTRUCTOR should have one element!");
if (!TREE_PURPOSE(elt)) return 0; // Not actually initialized?
if (!ConvertType(TREE_TYPE(TREE_PURPOSE(elt)))->isFirstClassType()) {
Value *V = Emit(TREE_VALUE(elt), DestLoc);
assert(V == 0 && "Aggregate value returned in a register?");
} else {
// Scalar value. Evaluate to a register, then do the store.
Value *V = Emit(TREE_VALUE(elt), 0);
DestLoc = CastToType(Instruction::BitCast, DestLoc,
PointerType::get(V->getType()));
Builder.CreateStore(V, DestLoc);
}
break;
}
return 0;
}
Constant *TreeConstantToLLVM::Convert(tree exp) {
// Some front-ends use constants other than the standard language-independent
// varieties, but which may still be output directly. Give the front-end a
// chance to convert EXP to a language-independent representation.
exp = lang_hooks.expand_constant (exp);
assert((TREE_CONSTANT(exp) || TREE_CODE(exp) == STRING_CST) &&
"Isn't a constant!");
switch (TREE_CODE(exp)) {
case FDESC_EXPR: // Needed on itanium
default:
debug_tree(exp);
assert(0 && "Unknown constant to convert!");
abort();
case INTEGER_CST: return ConvertINTEGER_CST(exp);
case REAL_CST: return ConvertREAL_CST(exp);
case VECTOR_CST: return ConvertVECTOR_CST(exp);
case STRING_CST: return ConvertSTRING_CST(exp);
case COMPLEX_CST: return ConvertCOMPLEX_CST(exp);
case NOP_EXPR: return ConvertNOP_EXPR(exp);
case CONVERT_EXPR: return ConvertCONVERT_EXPR(exp);
case PLUS_EXPR:
case MINUS_EXPR: return ConvertBinOp_CST(exp);
case CONSTRUCTOR: return ConvertCONSTRUCTOR(exp);
case VIEW_CONVERT_EXPR: return Convert(TREE_OPERAND(exp, 0));
case ADDR_EXPR:
return ConstantExpr::getBitCast(EmitLV(TREE_OPERAND(exp, 0)),
ConvertType(TREE_TYPE(exp)));
}
}
Constant *TreeConstantToLLVM::ConvertINTEGER_CST(tree exp) {
// Convert it to a uint64_t.
uint64_t IntValue = getINTEGER_CSTVal(exp);
// Build the value as a ulong constant, then constant fold it to the right
// type. This handles overflow and other things appropriately.
const Type *Ty = ConvertType(TREE_TYPE(exp));
ConstantInt *C = ConstantInt::get(Type::Int64Ty, IntValue);
// The destination type can be a pointer, integer or floating point
// so we need a generalized cast here
Instruction::CastOps opcode = CastInst::getCastOpcode(C, false, Ty,
!TYPE_UNSIGNED(TREE_TYPE(exp)));
return ConstantExpr::getCast(opcode, C, Ty);
}
Constant *TreeConstantToLLVM::ConvertREAL_CST(tree exp) {
const Type *Ty = ConvertType(TREE_TYPE(exp));
assert(Ty->isFloatingPoint() && "Integer REAL_CST?");
long RealArr[2];
union {
int UArr[2];
double V;
};
REAL_VALUE_TO_TARGET_DOUBLE(TREE_REAL_CST(exp), RealArr);
// Here's how this works:
// REAL_VALUE_TO_TARGET_DOUBLE() will generate the floating point number
// as an array of integers in the hosts's representation. Each integer
// in the array will hold 32 bits of the result REGARDLESS OF THE HOST'S
// INTEGER SIZE.
//
// This, then, makes the conversion pretty simple. The tricky part is
// getting the byte ordering correct and make sure you don't print any
// more than 32 bits per integer on platforms with ints > 32 bits.
//
bool HostBigEndian = false;
#ifdef HOST_WORDS_BIG_ENDIAN
HostBigEndian = true;
#endif
UArr[0] = RealArr[0]; // Long -> int convert
UArr[1] = RealArr[1];
if (WORDS_BIG_ENDIAN != HostBigEndian)
std::swap(UArr[0], UArr[1]);
return ConstantFP::get(Ty, Ty==Type::FloatTy ? APFloat((float)V)
: APFloat(V));
}
Constant *TreeConstantToLLVM::ConvertVECTOR_CST(tree exp) {
if (TREE_VECTOR_CST_ELTS(exp)) {
std::vector<Constant*> Elts;
for (tree elt = TREE_VECTOR_CST_ELTS(exp); elt; elt = TREE_CHAIN(elt))
Elts.push_back(Convert(TREE_VALUE(elt)));
return ConstantVector::get(Elts);
} else {
return Constant::getNullValue(ConvertType(TREE_TYPE(exp)));
}
}
Constant *TreeConstantToLLVM::ConvertSTRING_CST(tree exp) {
const ArrayType *StrTy = cast<ArrayType>(ConvertType(TREE_TYPE(exp)));
const Type *ElTy = StrTy->getElementType();
unsigned Len = (unsigned)TREE_STRING_LENGTH(exp);
std::vector<Constant*> Elts;
if (ElTy == Type::Int8Ty) {
const unsigned char *InStr =(const unsigned char *)TREE_STRING_POINTER(exp);
for (unsigned i = 0; i != Len; ++i)
Elts.push_back(ConstantInt::get(Type::Int8Ty, InStr[i]));
} else if (ElTy == Type::Int16Ty) {
const unsigned short *InStr =
(const unsigned short *)TREE_STRING_POINTER(exp);
for (unsigned i = 0; i != Len; ++i)
Elts.push_back(ConstantInt::get(Type::Int16Ty, InStr[i]));
} else if (ElTy == Type::Int32Ty) {
const unsigned *InStr = (const unsigned *)TREE_STRING_POINTER(exp);
for (unsigned i = 0; i != Len; ++i)
Elts.push_back(ConstantInt::get(Type::Int32Ty, InStr[i]));
} else {
assert(0 && "Unknown character type!");
}
unsigned ConstantSize = StrTy->getNumElements();
if (Len != ConstantSize) {
// If this is a variable sized array type, set the length to Len.
if (ConstantSize == 0) {
tree Domain = TYPE_DOMAIN(TREE_TYPE(exp));
if (!Domain || !TYPE_MAX_VALUE(Domain)) {
ConstantSize = Len;
StrTy = ArrayType::get(ElTy, Len);
}
}
if (ConstantSize < Len) {
// Only some chars are being used, truncate the string: char X[2] = "foo";
Elts.resize(ConstantSize);
} else {
// Fill the end of the string with nulls.
Constant *C = Constant::getNullValue(ElTy);
for (; Len != ConstantSize; ++Len)
Elts.push_back(C);
}
}
return ConstantArray::get(StrTy, Elts);
}
Constant *TreeConstantToLLVM::ConvertCOMPLEX_CST(tree exp) {
std::vector<Constant*> Elts;
Elts.push_back(Convert(TREE_REALPART(exp)));
Elts.push_back(Convert(TREE_IMAGPART(exp)));
return ConstantStruct::get(Elts, false);
}
Constant *TreeConstantToLLVM::ConvertNOP_EXPR(tree exp) {
Constant *Elt = Convert(TREE_OPERAND(exp, 0));
const Type *Ty = ConvertType(TREE_TYPE(exp));
bool EltIsSigned = !TYPE_UNSIGNED(TREE_TYPE(TREE_OPERAND(exp, 0)));
bool TyIsSigned = !TYPE_UNSIGNED(TREE_TYPE(exp));
// If this is a structure-to-structure cast, just return the uncasted value.
if (!Elt->getType()->isFirstClassType() || !Ty->isFirstClassType())
return Elt;
// Elt and Ty can be integer, float or pointer here: need generalized cast
Instruction::CastOps opcode = CastInst::getCastOpcode(Elt, EltIsSigned,
Ty, TyIsSigned);
return ConstantExpr::getCast(opcode, Elt, Ty);
}
Constant *TreeConstantToLLVM::ConvertCONVERT_EXPR(tree exp) {
Constant *Elt = Convert(TREE_OPERAND(exp, 0));
bool EltIsSigned = !TYPE_UNSIGNED(TREE_TYPE(TREE_OPERAND(exp, 0)));
const Type *Ty = ConvertType(TREE_TYPE(exp));
bool TyIsSigned = !TYPE_UNSIGNED(TREE_TYPE(exp));
Instruction::CastOps opcode = CastInst::getCastOpcode(Elt, EltIsSigned, Ty,
TyIsSigned);
return ConstantExpr::getCast(opcode, Elt, Ty);
}
Constant *TreeConstantToLLVM::ConvertBinOp_CST(tree exp) {
Constant *LHS = Convert(TREE_OPERAND(exp, 0));
bool LHSIsSigned = !TYPE_UNSIGNED(TREE_TYPE(TREE_OPERAND(exp,0)));
Constant *RHS = Convert(TREE_OPERAND(exp, 1));
bool RHSIsSigned = !TYPE_UNSIGNED(TREE_TYPE(TREE_OPERAND(exp,1)));
Instruction::CastOps opcode;
if (isa<PointerType>(LHS->getType())) {
const Type *IntPtrTy = getTargetData().getIntPtrType();
opcode = CastInst::getCastOpcode(LHS, LHSIsSigned, IntPtrTy, false);
LHS = ConstantExpr::getCast(opcode, LHS, IntPtrTy);
opcode = CastInst::getCastOpcode(RHS, RHSIsSigned, IntPtrTy, false);
RHS = ConstantExpr::getCast(opcode, RHS, IntPtrTy);
}
Constant *Result;
switch (TREE_CODE(exp)) {
default: assert(0 && "Unexpected case!");
case PLUS_EXPR: Result = ConstantExpr::getAdd(LHS, RHS); break;
case MINUS_EXPR: Result = ConstantExpr::getSub(LHS, RHS); break;
}
const Type *Ty = ConvertType(TREE_TYPE(exp));
bool TyIsSigned = !TYPE_UNSIGNED(TREE_TYPE(exp));
opcode = CastInst::getCastOpcode(Result, LHSIsSigned, Ty, TyIsSigned);
return ConstantExpr::getCast(opcode, Result, Ty);
}
Constant *TreeConstantToLLVM::ConvertCONSTRUCTOR(tree exp) {
if (CONSTRUCTOR_ELTS(exp) == 0) // All zeros?
return Constant::getNullValue(ConvertType(TREE_TYPE(exp)));
switch (TREE_CODE(TREE_TYPE(exp))) {
default:
debug_tree(exp);
assert(0 && "Unknown ctor!");
case VECTOR_TYPE:
case ARRAY_TYPE: return ConvertArrayCONSTRUCTOR(exp);
case RECORD_TYPE: return ConvertRecordCONSTRUCTOR(exp);
case UNION_TYPE: return ConvertUnionCONSTRUCTOR(exp);
}
}
Constant *TreeConstantToLLVM::ConvertArrayCONSTRUCTOR(tree exp) {
// Vectors are like arrays, but the domain is stored via an array
// type indirectly.
assert(TREE_CODE(TREE_TYPE(exp)) != VECTOR_TYPE &&
"VECTOR_TYPE's haven't been tested!");
// If we have a lower bound for the range of the type, get it. */
tree Domain = TYPE_DOMAIN(TREE_TYPE(exp));
tree min_element = size_zero_node;
if (Domain && TYPE_MIN_VALUE(Domain))
min_element = fold_convert(sizetype, TYPE_MIN_VALUE(Domain));
std::vector<Constant*> ResultElts;
Constant *SomeVal = 0;
if (Domain && TYPE_MAX_VALUE(Domain)) {
tree max_element = fold_convert(sizetype, TYPE_MAX_VALUE(Domain));
tree size = size_binop (MINUS_EXPR, max_element, min_element);
size = size_binop (PLUS_EXPR, size, size_one_node);
if (host_integerp(size, 1))
ResultElts.resize(tree_low_cst(size, 1));
}
unsigned NextFieldToFill = 0;
for (tree elt = CONSTRUCTOR_ELTS(exp); elt; elt = TREE_CHAIN(elt)) {
// Find and decode the constructor's value.
Constant *Val = Convert(TREE_VALUE(elt));
SomeVal = Val;
// Get the index position of the element within the array. Note that this
// can be NULL_TREE, which means that it belongs in the next available slot.
tree index = TREE_PURPOSE(elt);
// The first and last field to fill in, inclusive.
unsigned FieldOffset, FieldLastOffset;
if (index && TREE_CODE(index) == RANGE_EXPR) {
tree first = fold_convert (sizetype, TREE_OPERAND(index, 0));
tree last = fold_convert (sizetype, TREE_OPERAND(index, 1));
first = size_binop (MINUS_EXPR, first, min_element);
last = size_binop (MINUS_EXPR, last, min_element);
assert(host_integerp(first, 1) && host_integerp(last, 1) &&
"Unknown range_expr!");
FieldOffset = tree_low_cst(first, 1);
FieldLastOffset = tree_low_cst(last, 1);
} else if (index) {
index = size_binop (MINUS_EXPR, fold_convert (sizetype, index),
min_element);
assert(host_integerp(index, 1));
FieldOffset = tree_low_cst(index, 1);
FieldLastOffset = FieldOffset;
} else {
FieldOffset = NextFieldToFill;
FieldLastOffset = FieldOffset;
}
// Process all of the elements in the range.
for (--FieldOffset; FieldOffset != FieldLastOffset; ) {
++FieldOffset;
if (FieldOffset == ResultElts.size())
ResultElts.push_back(Val);
else {
if (FieldOffset >= ResultElts.size())
ResultElts.resize(FieldOffset+1);
ResultElts[FieldOffset] = Val;
}
NextFieldToFill = FieldOffset+1;
}
}
// Zero length array.
if (ResultElts.empty())
return ConstantArray::get(cast<ArrayType>(ConvertType(TREE_TYPE(exp))),
ResultElts);
assert(SomeVal && "If we had some initializer, we should have some value!");
// Do a post-pass over all of the elements. We're taking care of two things
// here:
// #1. If any elements did not have initializers specified, provide them
// with a null init.
// #2. If any of the elements have different types, return a struct instead
// of an array. This can occur in cases where we have an array of
// unions, and the various unions had different pieces init'd.
const Type *ElTy = SomeVal->getType();
Constant *Filler = Constant::getNullValue(ElTy);
bool AllEltsSameType = true;
for (unsigned i = 0, e = ResultElts.size(); i != e; ++i) {
if (ResultElts[i] == 0)
ResultElts[i] = Filler;
else if (ResultElts[i]->getType() != ElTy)
AllEltsSameType = false;
}
if (AllEltsSameType)
return ConstantArray::get(ArrayType::get(ElTy, ResultElts.size()),
ResultElts);
return ConstantStruct::get(ResultElts, false);
}
/// InsertBitFieldValue - Process the assignment of a bitfield value into an
/// LLVM struct value. Val may be null if nothing has been assigned into this
/// field, so FieldTy indicates the type of the LLVM struct type to use.
static Constant *InsertBitFieldValue(uint64_t ValToInsert,
unsigned NumBitsToInsert,
unsigned OffsetToBitFieldStart,
unsigned FieldBitSize,
Constant *Val, const Type *FieldTy) {
if (FieldTy->isInteger()) {
uint64_t ExistingVal;
if (Val == 0)
ExistingVal = 0;
else {
assert(isa<ConstantInt>(Val) && "Bitfield shared with non-bit-field?");
ExistingVal = cast<ConstantInt>(Val)->getZExtValue();
}
// Compute the value to insert, and the mask to use.
uint64_t FieldMask;
if (BITS_BIG_ENDIAN) {
FieldMask = ~0ULL >> (64-NumBitsToInsert);
FieldMask <<= FieldBitSize-(OffsetToBitFieldStart+NumBitsToInsert);
ValToInsert <<= FieldBitSize-(OffsetToBitFieldStart+NumBitsToInsert);
} else {
FieldMask = ~0ULL >> (64-NumBitsToInsert);
FieldMask <<= OffsetToBitFieldStart;
ValToInsert <<= OffsetToBitFieldStart;
}
// Insert the new value into the field and return it.
uint64_t NewVal = (ExistingVal & ~FieldMask) | ValToInsert;
return ConstantExpr::getTruncOrBitCast(ConstantInt::get(Type::Int64Ty,
NewVal), FieldTy);
} else {
// Otherwise, this is initializing part of an array of bytes. Recursively
// insert each byte.
assert(isa<ArrayType>(FieldTy) &&
cast<ArrayType>(FieldTy)->getElementType() == Type::Int8Ty &&
"Not an array of bytes?");
// Expand the already parsed initializer into its elements if it is a
// ConstantArray or ConstantAggregateZero.
std::vector<Constant*> Elts;
Elts.resize(cast<ArrayType>(FieldTy)->getNumElements());
if (Val) {
if (ConstantArray *CA = dyn_cast<ConstantArray>(Val)) {
for (unsigned i = 0, e = Elts.size(); i != e; ++i)
Elts[i] = CA->getOperand(i);
} else {
assert(isa<ConstantAggregateZero>(Val) && "Unexpected initializer!");
Constant *Elt = Constant::getNullValue(Type::Int8Ty);
for (unsigned i = 0, e = Elts.size(); i != e; ++i)
Elts[i] = Elt;
}
}
// Loop over all of our elements, inserting pieces into each one as
// appropriate.
unsigned i = OffsetToBitFieldStart/8; // Skip to first byte
OffsetToBitFieldStart &= 7;
for (; NumBitsToInsert; ++i) {
assert(i < Elts.size() && "Inserting out of range!");
unsigned NumEltBitsToInsert = std::min(8-OffsetToBitFieldStart,
NumBitsToInsert);
uint64_t EltValToInsert;
if (BITS_BIG_ENDIAN) {
// If this is a big-endian bit-field, take the top NumBitsToInsert
// bits from the bitfield value.
EltValToInsert = ValToInsert >> (NumBitsToInsert-NumEltBitsToInsert);
// Clear the handled bits from BitfieldVal.
ValToInsert &= (1ULL << (NumBitsToInsert-NumEltBitsToInsert))-1;
} else {
// If this is little-endian bit-field, take the bottom NumBitsToInsert
// bits from the bitfield value.
EltValToInsert = ValToInsert & (1ULL << NumEltBitsToInsert)-1;
ValToInsert >>= NumEltBitsToInsert;
}
Elts[i] = InsertBitFieldValue(EltValToInsert, NumEltBitsToInsert,
OffsetToBitFieldStart, 8, Elts[i],
Type::Int8Ty);
// Advance for next element.
OffsetToBitFieldStart = 0;
NumBitsToInsert -= NumEltBitsToInsert;
}
// Pad extra array elements. This may happens when one llvm field
// is used to access two struct fields and llvm field is represented
// as an array of bytes.
for (; i < Elts.size(); ++i)
Elts[i] = ConstantInt::get((cast<ArrayType>(FieldTy))->getElementType(), 0);
return ConstantArray::get(cast<ArrayType>(FieldTy), Elts);
}
}
/// ProcessBitFieldInitialization - Handle a static initialization of a
/// RECORD_TYPE field that is a bitfield.
static void ProcessBitFieldInitialization(tree Field, Value *Val,
const StructType *STy,
std::vector<Constant*> &ResultElts) {
// Get the offset and size of the bitfield, in bits.
unsigned BitfieldBitOffset = getFieldOffsetInBits(Field);
unsigned BitfieldSize = TREE_INT_CST_LOW(DECL_SIZE(Field));
// Get the value to insert into the bitfield.
assert(Val->getType()->isInteger() && "Bitfield initializer isn't int!");
assert(isa<ConstantInt>(Val) && "Non-constant bitfield initializer!");
uint64_t BitfieldVal = cast<ConstantInt>(Val)->getZExtValue();
// Ensure that the top bits (which don't go into the bitfield) are zero.
BitfieldVal &= ~0ULL >> (64-BitfieldSize);
// Get the struct field layout info for this struct.
const StructLayout *STyLayout = getTargetData().getStructLayout(STy);
// If this is a bitfield, we know that FieldNo is the *first* LLVM field
// that contains bits from the bitfield overlayed with the declared type of
// the bitfield. This bitfield value may be spread across multiple fields, or
// it may be just this field, or it may just be a small part of this field.
unsigned FieldNo = cast<ConstantInt>(DECL_LLVM(Field))->getZExtValue();
assert(FieldNo < ResultElts.size() && "Invalid struct field number!");
// Get the offset and size of the LLVM field.
uint64_t STyFieldBitOffs = STyLayout->getElementOffset(FieldNo)*8;
assert(BitfieldBitOffset >= STyFieldBitOffs &&
"This bitfield doesn't start in this LLVM field!");
unsigned OffsetToBitFieldStart = BitfieldBitOffset-STyFieldBitOffs;
// Loop over all of the fields this bitfield is part of. This is usually just
// one, but can be several in some cases.
for (; BitfieldSize; ++FieldNo) {
assert(STyFieldBitOffs == STyLayout->getElementOffset(FieldNo)*8 &&
"Bitfield LLVM fields are not exactly consecutive in memory!");
// Compute overlap of this bitfield with this LLVM field, then call a
// function to insert (the STy element may be an array of bytes or
// something).
const Type *STyFieldTy = STy->getElementType(FieldNo);
unsigned STyFieldBitSize = getTargetData().getTypeSize(STyFieldTy)*8;
// If the bitfield starts after this field, advance to the next field. This
// can happen because we start looking at the first element overlapped by
// an aligned instance of the declared type.
if (OffsetToBitFieldStart >= STyFieldBitSize) {
OffsetToBitFieldStart -= STyFieldBitSize;
STyFieldBitOffs += STyFieldBitSize;
continue;
}
// We are inserting part of 'Val' into this LLVM field. The start bit
// is OffsetToBitFieldStart. Compute the number of bits from this bitfield
// we are inserting into this LLVM field.
unsigned NumBitsToInsert =
std::min(BitfieldSize, STyFieldBitSize-OffsetToBitFieldStart);
// Compute the NumBitsToInsert-wide value that we are going to insert
// into this field as an ulong integer constant value.
uint64_t ValToInsert;
if (BITS_BIG_ENDIAN) {
// If this is a big-endian bit-field, take the top NumBitsToInsert
// bits from the bitfield value.
ValToInsert = BitfieldVal >> (BitfieldSize-NumBitsToInsert);
// Clear the handled bits from BitfieldVal.
BitfieldVal &= (1ULL << (BitfieldSize-NumBitsToInsert))-1;
} else {
// If this is little-endian bit-field, take the bottom NumBitsToInsert
// bits from the bitfield value.
ValToInsert = BitfieldVal & (1ULL << NumBitsToInsert)-1;
BitfieldVal >>= NumBitsToInsert;
}
ResultElts[FieldNo] = InsertBitFieldValue(ValToInsert, NumBitsToInsert,
OffsetToBitFieldStart,
STyFieldBitSize,
ResultElts[FieldNo], STyFieldTy);
// If this bitfield splits across multiple LLVM fields, update these
// values for the next field.
BitfieldSize -= NumBitsToInsert;
STyFieldBitOffs += STyFieldBitSize;
OffsetToBitFieldStart = 0;
}
}
/// ConvertStructFieldInitializerToType - Convert the input value to a new type,
/// when constructing the field initializers for a constant CONSTRUCTOR object.
static Constant *ConvertStructFieldInitializerToType(Constant *Val,
const Type *FieldTy) {
const TargetData &TD = getTargetData();
assert(TD.getTypeSize(FieldTy) == TD.getTypeSize(Val->getType()) &&
"Mismatched initializer type isn't same size as initializer!");
// If this is an integer initializer for an array of ubytes, we are
// initializing an unaligned integer field. Break the integer initializer up
// into pieces.
if (ConstantInt *CI = dyn_cast<ConstantInt>(Val)) {
if (const ArrayType *ATy = dyn_cast<ArrayType>(FieldTy))
if (ATy->getElementType() == Type::Int8Ty) {
std::vector<Constant*> ArrayElts;
uint64_t Val = CI->getZExtValue();
for (unsigned i = 0, e = ATy->getNumElements(); i != e; ++i) {
unsigned char EltVal;
if (TD.isLittleEndian()) {
EltVal = (Val >> 8*i) & 0xFF;
} else {
EltVal = (Val >> 8*(e-i-1)) & 0xFF;
}
ArrayElts.push_back(ConstantInt::get(Type::Int8Ty, EltVal));
}
return ConstantArray::get(ATy, ArrayElts);
}
}
// Otherwise, we can get away with this initialization.
assert(TD.getABITypeAlignment(FieldTy) >=
TD.getABITypeAlignment(Val->getType()) &&
"Field initialize is over aligned for LLVM type!");
return Val;
}
Constant *TreeConstantToLLVM::ConvertRecordCONSTRUCTOR(tree exp) {
const StructType *STy = cast<StructType>(ConvertType(TREE_TYPE(exp)));
std::vector<Constant*> ResultElts;
ResultElts.resize(STy->getNumElements());
tree NextField = TYPE_FIELDS(TREE_TYPE(exp));
for (tree elt = CONSTRUCTOR_ELTS(exp); elt; elt = TREE_CHAIN(elt)) {
tree Field = TREE_PURPOSE(elt); // The fielddecl for the field.
unsigned FieldNo;
if (Field == 0) { // If an explicit field is specified, use it.
Field = NextField;
// Advance to the next FIELD_DECL, skipping over other structure members
// (e.g. enums).
for (; 1; Field = TREE_CHAIN(Field)) {
assert(Field && "Fell off end of record!");
if (TREE_CODE(Field) == FIELD_DECL) break;
}
}
// Decode the field's value.
Constant *Val = Convert(TREE_VALUE(elt));
// If the field is a bitfield, it could be spread across multiple fields and
// may start at some bit offset.
if (DECL_BIT_FIELD_TYPE(Field)) {
ProcessBitFieldInitialization(Field, Val, STy, ResultElts);
} else {
// If not, things are much simpler.
assert(DECL_LLVM_SET_P(Field) && "Struct not laid out for LLVM?");
unsigned FieldNo = cast<ConstantInt>(DECL_LLVM(Field))->getZExtValue();
assert(FieldNo < ResultElts.size() && "Invalid struct field number!");
// Example: struct X { int A; char C[]; } x = { 4, "foo" };
assert(TYPE_SIZE(TREE_TYPE(Field)) ||
(FieldNo == ResultElts.size()-1 &&
isStructWithVarSizeArrayAtEnd(STy))
&& "field with no size is not array at end of struct!");
// If this is an initialization of a global that ends with a variable
// sized array at its end, and the initializer has a non-zero number of
// elements, then Val contains the actual type for the array. Otherwise,
// we know that the initializer has to match the element type of the LLVM
// structure field. If not, then there is something that is not
// straight-forward going on. For example, we could be initializing an
// unaligned integer field (e.g. due to attribute packed) with an
// integer. The struct field will have type [4 x ubyte] instead of
// "int" for example. If we ignored this, we would lay out the
// initializer wrong.
if (TYPE_SIZE(TREE_TYPE(Field)) &&
Val->getType() != STy->getElementType(FieldNo))
Val = ConvertStructFieldInitializerToType(Val,
STy->getElementType(FieldNo));
ResultElts[FieldNo] = Val;
}
NextField = TREE_CHAIN(Field);
}
// Fill in null elements with zeros.
for (unsigned i = 0, e = ResultElts.size(); i != e; ++i)
if (ResultElts[i] == 0)
ResultElts[i] = Constant::getNullValue(STy->getElementType(i));
return ConstantStruct::get(ResultElts, STy->isPacked());
}
Constant *TreeConstantToLLVM::ConvertUnionCONSTRUCTOR(tree exp) {
assert(CONSTRUCTOR_ELTS(exp) && "Union CONSTRUCTOR has no elements? Zero?");
tree elt = CONSTRUCTOR_ELTS(exp);
assert(TREE_CHAIN(elt) == 0 && "Union CONSTRUCTOR with multiple elements?");
std::vector<Constant*> Elts;
// Convert the constant itself.
Elts.push_back(Convert(TREE_VALUE(elt)));
// If the union has a fixed size, and if the value we converted isn't large
// enough to fill all the bits, add a zero initialized array at the end to pad
// it out.
tree UnionType = TREE_TYPE(exp);
if (TYPE_SIZE(UnionType) && TREE_CODE(TYPE_SIZE(UnionType)) == INTEGER_CST) {
unsigned UnionSize = ((unsigned)TREE_INT_CST_LOW(TYPE_SIZE(UnionType))+7)/8;
unsigned InitSize = getTargetData().getTypeSize(Elts[0]->getType());
if (UnionSize != InitSize) {
const Type *FillTy;
assert(UnionSize > InitSize && "Init shouldn't be larger than union!");
if (UnionSize - InitSize == 1)
FillTy = Type::Int8Ty;
else
FillTy = ArrayType::get(Type::Int8Ty, UnionSize - InitSize);
Elts.push_back(Constant::getNullValue(FillTy));
}
}
return ConstantStruct::get(Elts, false);
}
//===----------------------------------------------------------------------===//
// ... Constant Expressions L-Values ...
//===----------------------------------------------------------------------===//
Constant *TreeConstantToLLVM::EmitLV(tree exp) {
switch (TREE_CODE(exp)) {
default:
debug_tree(exp);
assert(0 && "Unknown constant lvalue to convert!");
abort();
case FUNCTION_DECL:
case CONST_DECL:
case VAR_DECL: return EmitLV_Decl(exp);
case LABEL_DECL: return EmitLV_LABEL_DECL(exp);
case STRING_CST: return EmitLV_STRING_CST(exp);
case COMPONENT_REF: return EmitLV_COMPONENT_REF(exp);
case ARRAY_RANGE_REF:
case ARRAY_REF: return EmitLV_ARRAY_REF(exp);
case INDIRECT_REF:
// The lvalue is just the address.
return Convert(TREE_OPERAND(exp, 0));
case COMPOUND_LITERAL_EXPR: // FIXME: not gimple - defined by C front-end
return EmitLV(COMPOUND_LITERAL_EXPR_DECL(exp));
}
}
Constant *TreeConstantToLLVM::EmitLV_Decl(tree exp) {
GlobalValue *Val = cast<GlobalValue>(DECL_LLVM(exp));
// Ensure variable marked as used even if it doesn't go through a parser. If
// it hasn't been used yet, write out an external definition.
if (!TREE_USED(exp)) {
assemble_external(exp);
TREE_USED(exp) = 1;
Val = cast<GlobalValue>(DECL_LLVM(exp));
}
// If this is an aggregate CONST_DECL, emit it to LLVM now. GCC happens to
// get this case right by forcing the initializer into memory.
if (TREE_CODE(exp) == CONST_DECL) {
if (DECL_INITIAL(exp) && Val->isDeclaration()) {
emit_global_to_llvm(exp);
// Decl could have change if it changed type.
Val = cast<GlobalValue>(DECL_LLVM(exp));
}
} else {
// Otherwise, inform cgraph that we used the global.
mark_decl_referenced(exp);
if (tree ID = DECL_ASSEMBLER_NAME(exp))
mark_referenced(ID);
}
return Val;
}
/// EmitLV_LABEL_DECL - Someone took the address of a label.
Constant *TreeConstantToLLVM::EmitLV_LABEL_DECL(tree exp) {
assert(TheTreeToLLVM &&
"taking the address of a label while not compiling the function!");
// Figure out which function this is for, verify it's the one we're compiling.
if (DECL_CONTEXT(exp)) {
assert(TREE_CODE(DECL_CONTEXT(exp)) == FUNCTION_DECL &&
"Address of label in nested function?");
assert(TheTreeToLLVM->getFUNCTION_DECL() == DECL_CONTEXT(exp) &&
"Taking the address of a label that isn't in the current fn!?");
}
BasicBlock *BB = getLabelDeclBlock(exp);
Constant *C = TheTreeToLLVM->getIndirectGotoBlockNumber(BB);
return ConstantExpr::getIntToPtr(C, PointerType::get(Type::Int8Ty));
}
Constant *TreeConstantToLLVM::EmitLV_STRING_CST(tree exp) {
Constant *Init = TreeConstantToLLVM::ConvertSTRING_CST(exp);
// Support -fwritable-strings.
bool StringIsConstant = !flag_writable_strings;
GlobalVariable **SlotP = 0;
if (StringIsConstant) {
// Cache the string constants to avoid making obvious duplicate strings that
// have to be folded by the optimizer.
static std::map<Constant*, GlobalVariable*> StringCSTCache;
GlobalVariable *&Slot = StringCSTCache[Init];
if (Slot) return Slot;
SlotP = &Slot;
}
// Create a new string global.
GlobalVariable *GV = new GlobalVariable(Init->getType(), StringIsConstant,
GlobalVariable::InternalLinkage,
Init, ".str", TheModule);
if (SlotP) *SlotP = GV;
return GV;
}
Constant *TreeConstantToLLVM::EmitLV_ARRAY_REF(tree exp) {
tree Array = TREE_OPERAND(exp, 0);
tree ArrayType = TREE_TYPE(Array);
tree Index = TREE_OPERAND(exp, 1);
tree IndexType = TREE_TYPE(Index);
assert((TREE_CODE (ArrayType) == ARRAY_TYPE ||
TREE_CODE (ArrayType) == POINTER_TYPE ||
TREE_CODE (ArrayType) == REFERENCE_TYPE) &&
"Unknown ARRAY_REF!");
// Check for variable sized reference.
// FIXME: add support for array types where the size doesn't fit into 64 bits
assert(isArrayCompatible(ArrayType) || isSequentialCompatible(ArrayType)
&& "Cannot have globals with variable size!");
// As an LLVM extension, we allow ARRAY_REF with a pointer as the first
// operand. This construct maps directly to a getelementptr instruction.
Constant *ArrayAddr;
if (TREE_CODE (ArrayType) == ARRAY_TYPE) {
// First subtract the lower bound, if any, in the type of the index.
tree LowerBound = array_ref_low_bound(exp);
if (!integer_zerop(LowerBound))
Index = fold(build2(MINUS_EXPR, IndexType, Index, LowerBound));
ArrayAddr = EmitLV(Array);
} else {
ArrayAddr = Convert(Array);
}
Constant *IndexVal = Convert(Index);
const Type *IntPtrTy = getTargetData().getIntPtrType();
if (IndexVal->getType() != IntPtrTy)
IndexVal = ConstantExpr::getIntegerCast(IndexVal, IntPtrTy,
!TYPE_UNSIGNED(IndexType));
std::vector<Value*> Idx;
if (isArrayCompatible(ArrayType))
Idx.push_back(ConstantInt::get(Type::Int32Ty, 0));
Idx.push_back(IndexVal);
return ConstantExpr::getGetElementPtr(ArrayAddr, &Idx[0], Idx.size());
}
Constant *TreeConstantToLLVM::EmitLV_COMPONENT_REF(tree exp) {
Constant *StructAddrLV = EmitLV(TREE_OPERAND(exp, 0));
// Ensure that the struct type has been converted, so that the fielddecls
// are laid out.
const Type *StructTy = ConvertType(TREE_TYPE(TREE_OPERAND(exp, 0)));
tree FieldDecl = TREE_OPERAND(exp, 1);
StructAddrLV = ConstantExpr::getBitCast(StructAddrLV,
PointerType::get(StructTy));
const Type *FieldTy = ConvertType(TREE_TYPE(FieldDecl));
// BitStart - This is the actual offset of the field from the start of the
// struct, in bits. For bitfields this may be on a non-byte boundary.
unsigned BitStart = getComponentRefOffsetInBits(exp);
unsigned BitSize = 0;
Constant *FieldPtr;
const TargetData &TD = getTargetData();
tree field_offset = component_ref_field_offset (exp);
// If this is a normal field at a fixed offset from the start, handle it.
if (TREE_CODE(field_offset) == INTEGER_CST) {
assert(DECL_LLVM_SET_P(FieldDecl) && "Struct not laid out for LLVM?");
ConstantInt *CI = cast<ConstantInt>(DECL_LLVM(FieldDecl));
uint64_t MemberIndex = CI->getZExtValue();
std::vector<Value*> Idxs;
Idxs.push_back(Constant::getNullValue(Type::Int32Ty));
Idxs.push_back(CI);
FieldPtr = ConstantExpr::getGetElementPtr(StructAddrLV, &Idxs[0],
Idxs.size());
// Now that we did an offset from the start of the struct, subtract off
// the offset from BitStart.
if (MemberIndex) {
const StructLayout *SL = TD.getStructLayout(cast<StructType>(StructTy));
BitStart -= SL->getElementOffset(MemberIndex) * 8;
}
} else {
Constant *Offset = Convert(field_offset);
Constant *Ptr = ConstantExpr::getPtrToInt(StructAddrLV, Offset->getType());
Ptr = ConstantExpr::getAdd(Ptr, Offset);
FieldPtr = ConstantExpr::getIntToPtr(Ptr, PointerType::get(FieldTy));
}
if (DECL_BIT_FIELD_TYPE(FieldDecl)) {
FieldTy = ConvertType(DECL_BIT_FIELD_TYPE(FieldDecl));
FieldPtr = ConstantExpr::getBitCast(FieldPtr, PointerType::get(FieldTy));
}
assert(BitStart == 0 &&
"It's a bitfield reference or we didn't get to the field!");
return FieldPtr;
}
/* APPLE LOCAL end LLVM (ENTIRE FILE!) */
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