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llvm-project/clang/CodeGen/CGExpr.cpp

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//===--- CGExpr.cpp - Emit LLVM Code from Expressions ---------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by Chris Lattner and is distributed under
// the University of Illinois Open Source License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This contains code to emit Expr nodes as LLVM code.
//
//===----------------------------------------------------------------------===//
#include "CodeGenFunction.h"
#include "CodeGenModule.h"
#include "clang/AST/AST.h"
#include "llvm/Constants.h"
#include "llvm/DerivedTypes.h"
#include "llvm/Function.h"
#include "llvm/GlobalVariable.h"
#include "llvm/Support/MathExtras.h"
using namespace clang;
using namespace CodeGen;
//===--------------------------------------------------------------------===//
// Miscellaneous Helper Methods
//===--------------------------------------------------------------------===//
/// CreateTempAlloca - This creates a alloca and inserts it into the entry
/// block.
llvm::AllocaInst *CodeGenFunction::CreateTempAlloca(const llvm::Type *Ty,
const char *Name) {
return new llvm::AllocaInst(Ty, 0, Name, AllocaInsertPt);
}
/// EvaluateExprAsBool - Perform the usual unary conversions on the specified
/// expression and compare the result against zero, returning an Int1Ty value.
llvm::Value *CodeGenFunction::EvaluateExprAsBool(const Expr *E) {
QualType Ty;
RValue Val = EmitExprWithUsualUnaryConversions(E, Ty);
return ConvertScalarValueToBool(Val, Ty);
}
/// EmitLoadOfComplex - Given an RValue reference for a complex, emit code to
/// load the real and imaginary pieces, returning them as Real/Imag.
void CodeGenFunction::EmitLoadOfComplex(RValue V,
llvm::Value *&Real, llvm::Value *&Imag){
llvm::Value *Ptr = V.getAggregateAddr();
llvm::Constant *Zero = llvm::ConstantInt::get(llvm::Type::Int32Ty, 0);
llvm::Constant *One = llvm::ConstantInt::get(llvm::Type::Int32Ty, 1);
llvm::Value *RealPtr = Builder.CreateGEP(Ptr, Zero, Zero, "realp");
llvm::Value *ImagPtr = Builder.CreateGEP(Ptr, Zero, One, "imagp");
// FIXME: Handle volatility.
Real = Builder.CreateLoad(RealPtr, "real");
Imag = Builder.CreateLoad(ImagPtr, "imag");
}
/// EmitStoreOfComplex - Store the specified real/imag parts into the
/// specified value pointer.
void CodeGenFunction::EmitStoreOfComplex(llvm::Value *Real, llvm::Value *Imag,
llvm::Value *ResPtr) {
llvm::Constant *Zero = llvm::ConstantInt::get(llvm::Type::Int32Ty, 0);
llvm::Constant *One = llvm::ConstantInt::get(llvm::Type::Int32Ty, 1);
llvm::Value *RealPtr = Builder.CreateGEP(ResPtr, Zero, Zero, "real");
llvm::Value *ImagPtr = Builder.CreateGEP(ResPtr, Zero, One, "imag");
// FIXME: Handle volatility.
Builder.CreateStore(Real, RealPtr);
Builder.CreateStore(Imag, ImagPtr);
}
//===--------------------------------------------------------------------===//
// Conversions
//===--------------------------------------------------------------------===//
/// EmitConversion - Convert the value specied by Val, whose type is ValTy, to
/// the type specified by DstTy, following the rules of C99 6.3.
RValue CodeGenFunction::EmitConversion(RValue Val, QualType ValTy,
QualType DstTy) {
ValTy = ValTy.getCanonicalType();
DstTy = DstTy.getCanonicalType();
if (ValTy == DstTy) return Val;
// Handle conversions to bool first, they are special: comparisons against 0.
if (const BuiltinType *DestBT = dyn_cast<BuiltinType>(DstTy))
if (DestBT->getKind() == BuiltinType::Bool)
return RValue::get(ConvertScalarValueToBool(Val, ValTy));
// Handle pointer conversions next: pointers can only be converted to/from
// other pointers and integers.
if (isa<PointerType>(DstTy)) {
const llvm::Type *DestTy = ConvertType(DstTy);
// The source value may be an integer, or a pointer.
assert(Val.isScalar() && "Can only convert from integer or pointer");
if (isa<llvm::PointerType>(Val.getVal()->getType()))
return RValue::get(Builder.CreateBitCast(Val.getVal(), DestTy, "conv"));
assert(ValTy->isIntegerType() && "Not ptr->ptr or int->ptr conversion?");
return RValue::get(Builder.CreateIntToPtr(Val.getVal(), DestTy, "conv"));
}
if (isa<PointerType>(ValTy)) {
// Must be an ptr to int cast.
const llvm::Type *DestTy = ConvertType(DstTy);
assert(isa<llvm::IntegerType>(DestTy) && "not ptr->int?");
return RValue::get(Builder.CreateIntToPtr(Val.getVal(), DestTy, "conv"));
}
// Finally, we have the arithmetic types: real int/float and complex
// int/float. Handle real->real conversions first, they are the most
// common.
if (Val.isScalar() && DstTy->isRealType()) {
// We know that these are representable as scalars in LLVM, convert to LLVM
// types since they are easier to reason about.
llvm::Value *SrcVal = Val.getVal();
const llvm::Type *DestTy = ConvertType(DstTy);
if (SrcVal->getType() == DestTy) return Val;
llvm::Value *Result;
if (isa<llvm::IntegerType>(SrcVal->getType())) {
bool InputSigned = ValTy->isSignedIntegerType();
if (isa<llvm::IntegerType>(DestTy))
Result = Builder.CreateIntCast(SrcVal, DestTy, InputSigned, "conv");
else if (InputSigned)
Result = Builder.CreateSIToFP(SrcVal, DestTy, "conv");
else
Result = Builder.CreateUIToFP(SrcVal, DestTy, "conv");
} else {
assert(SrcVal->getType()->isFloatingPoint() && "Unknown real conversion");
if (isa<llvm::IntegerType>(DestTy)) {
if (DstTy->isSignedIntegerType())
Result = Builder.CreateFPToSI(SrcVal, DestTy, "conv");
else
Result = Builder.CreateFPToUI(SrcVal, DestTy, "conv");
} else {
assert(DestTy->isFloatingPoint() && "Unknown real conversion");
if (DestTy->getTypeID() < SrcVal->getType()->getTypeID())
Result = Builder.CreateFPTrunc(SrcVal, DestTy, "conv");
else
Result = Builder.CreateFPExt(SrcVal, DestTy, "conv");
}
}
return RValue::get(Result);
}
assert(0 && "FIXME: We don't support complex conversions yet!");
}
/// ConvertScalarValueToBool - Convert the specified expression value to a
/// boolean (i1) truth value. This is equivalent to "Val == 0".
llvm::Value *CodeGenFunction::ConvertScalarValueToBool(RValue Val, QualType Ty){
Ty = Ty.getCanonicalType();
llvm::Value *Result;
if (const BuiltinType *BT = dyn_cast<BuiltinType>(Ty)) {
switch (BT->getKind()) {
default: assert(0 && "Unknown scalar value");
case BuiltinType::Bool:
Result = Val.getVal();
// Bool is already evaluated right.
assert(Result->getType() == llvm::Type::Int1Ty &&
"Unexpected bool value type!");
return Result;
case BuiltinType::Char_S:
case BuiltinType::Char_U:
case BuiltinType::SChar:
case BuiltinType::UChar:
case BuiltinType::Short:
case BuiltinType::UShort:
case BuiltinType::Int:
case BuiltinType::UInt:
case BuiltinType::Long:
case BuiltinType::ULong:
case BuiltinType::LongLong:
case BuiltinType::ULongLong:
// Code below handles simple integers.
break;
case BuiltinType::Float:
case BuiltinType::Double:
case BuiltinType::LongDouble: {
// Compare against 0.0 for fp scalars.
Result = Val.getVal();
llvm::Value *Zero = llvm::Constant::getNullValue(Result->getType());
// FIXME: llvm-gcc produces a une comparison: validate this is right.
Result = Builder.CreateFCmpUNE(Result, Zero, "tobool");
return Result;
}
}
} else if (isa<PointerType>(Ty) ||
cast<TagType>(Ty)->getDecl()->getKind() == Decl::Enum) {
// Code below handles this fine.
} else {
assert(isa<ComplexType>(Ty) && "Unknwon type!");
assert(0 && "FIXME: comparisons against complex not implemented yet");
}
// Usual case for integers, pointers, and enums: compare against zero.
Result = Val.getVal();
// Because of the type rules of C, we often end up computing a logical value,
// then zero extending it to int, then wanting it as a logical value again.
// Optimize this common case.
if (llvm::ZExtInst *ZI = dyn_cast<llvm::ZExtInst>(Result)) {
if (ZI->getOperand(0)->getType() == llvm::Type::Int1Ty) {
Result = ZI->getOperand(0);
ZI->eraseFromParent();
return Result;
}
}
llvm::Value *Zero = llvm::Constant::getNullValue(Result->getType());
return Builder.CreateICmpNE(Result, Zero, "tobool");
}
//===----------------------------------------------------------------------===//
// LValue Expression Emission
//===----------------------------------------------------------------------===//
/// EmitLValue - Emit code to compute a designator that specifies the location
/// of the expression.
///
/// This can return one of two things: a simple address or a bitfield
/// reference. In either case, the LLVM Value* in the LValue structure is
/// guaranteed to be an LLVM pointer type.
///
/// If this returns a bitfield reference, nothing about the pointee type of
/// the LLVM value is known: For example, it may not be a pointer to an
/// integer.
///
/// If this returns a normal address, and if the lvalue's C type is fixed
/// size, this method guarantees that the returned pointer type will point to
/// an LLVM type of the same size of the lvalue's type. If the lvalue has a
/// variable length type, this is not possible.
///
LValue CodeGenFunction::EmitLValue(const Expr *E) {
switch (E->getStmtClass()) {
default:
fprintf(stderr, "Unimplemented lvalue expr!\n");
E->dump();
return LValue::MakeAddr(llvm::UndefValue::get(
llvm::PointerType::get(llvm::Type::Int32Ty)));
case Expr::DeclRefExprClass: return EmitDeclRefLValue(cast<DeclRefExpr>(E));
case Expr::ParenExprClass:return EmitLValue(cast<ParenExpr>(E)->getSubExpr());
case Expr::PreDefinedExprClass:
return EmitPreDefinedLValue(cast<PreDefinedExpr>(E));
case Expr::StringLiteralClass:
return EmitStringLiteralLValue(cast<StringLiteral>(E));
case Expr::UnaryOperatorClass:
return EmitUnaryOpLValue(cast<UnaryOperator>(E));
case Expr::ArraySubscriptExprClass:
return EmitArraySubscriptExpr(cast<ArraySubscriptExpr>(E));
}
}
/// EmitLoadOfLValue - Given an expression that represents a value lvalue,
/// this method emits the address of the lvalue, then loads the result as an
/// rvalue, returning the rvalue.
RValue CodeGenFunction::EmitLoadOfLValue(LValue LV, QualType ExprType) {
ExprType = ExprType.getCanonicalType();
if (LV.isSimple()) {
llvm::Value *Ptr = LV.getAddress();
const llvm::Type *EltTy =
cast<llvm::PointerType>(Ptr->getType())->getElementType();
// Simple scalar l-value.
if (EltTy->isFirstClassType())
return RValue::get(Builder.CreateLoad(Ptr, "tmp"));
// Otherwise, we have an aggregate lvalue.
return RValue::getAggregate(Ptr);
}
if (LV.isVectorElt()) {
llvm::Value *Vec = Builder.CreateLoad(LV.getVectorAddr(), "tmp");
return RValue::get(Builder.CreateExtractElement(Vec, LV.getVectorIdx(),
"vecext"));
}
assert(0 && "Bitfield ref not impl!");
}
RValue CodeGenFunction::EmitLoadOfLValue(const Expr *E) {
return EmitLoadOfLValue(EmitLValue(E), E->getType());
}
/// EmitStoreThroughLValue - Store the specified rvalue into the specified
/// lvalue, where both are guaranteed to the have the same type, and that type
/// is 'Ty'.
void CodeGenFunction::EmitStoreThroughLValue(RValue Src, LValue Dst,
QualType Ty) {
if (Dst.isVectorElt()) {
// Read/modify/write the vector, inserting the new element.
// FIXME: Volatility.
llvm::Value *Vec = Builder.CreateLoad(Dst.getVectorAddr(), "tmp");
Vec = Builder.CreateInsertElement(Vec, Src.getVal(),
Dst.getVectorIdx(), "vecins");
Builder.CreateStore(Vec, Dst.getVectorAddr());
return;
}
assert(Dst.isSimple() && "FIXME: Don't support store to bitfield yet");
llvm::Value *DstAddr = Dst.getAddress();
if (Src.isScalar()) {
// FIXME: Handle volatility etc.
const llvm::Type *SrcTy = Src.getVal()->getType();
const llvm::Type *AddrTy =
cast<llvm::PointerType>(DstAddr->getType())->getElementType();
if (AddrTy != SrcTy)
DstAddr = Builder.CreateBitCast(DstAddr, llvm::PointerType::get(SrcTy),
"storetmp");
Builder.CreateStore(Src.getVal(), DstAddr);
return;
}
// Don't use memcpy for complex numbers.
if (Ty->isComplexType()) {
llvm::Value *Real, *Imag;
EmitLoadOfComplex(Src, Real, Imag);
EmitStoreOfComplex(Real, Imag, Dst.getAddress());
return;
}
// Aggregate assignment turns into llvm.memcpy.
const llvm::Type *SBP = llvm::PointerType::get(llvm::Type::Int8Ty);
llvm::Value *SrcAddr = Src.getAggregateAddr();
if (DstAddr->getType() != SBP)
DstAddr = Builder.CreateBitCast(DstAddr, SBP, "tmp");
if (SrcAddr->getType() != SBP)
SrcAddr = Builder.CreateBitCast(SrcAddr, SBP, "tmp");
unsigned Align = 1; // FIXME: Compute type alignments.
unsigned Size = 1234; // FIXME: Compute type sizes.
// FIXME: Handle variable sized types.
const llvm::Type *IntPtr = llvm::IntegerType::get(LLVMPointerWidth);
llvm::Value *SizeVal = llvm::ConstantInt::get(IntPtr, Size);
llvm::Value *MemCpyOps[4] = {
DstAddr, SrcAddr, SizeVal,llvm::ConstantInt::get(llvm::Type::Int32Ty, Align)
};
Builder.CreateCall(CGM.getMemCpyFn(), MemCpyOps, MemCpyOps+4);
}
LValue CodeGenFunction::EmitDeclRefLValue(const DeclRefExpr *E) {
const Decl *D = E->getDecl();
if (isa<BlockVarDecl>(D) || isa<ParmVarDecl>(D)) {
llvm::Value *V = LocalDeclMap[D];
assert(V && "BlockVarDecl not entered in LocalDeclMap?");
return LValue::MakeAddr(V);
} else if (isa<FunctionDecl>(D) || isa<FileVarDecl>(D)) {
return LValue::MakeAddr(CGM.GetAddrOfGlobalDecl(D));
}
assert(0 && "Unimp declref");
}
LValue CodeGenFunction::EmitUnaryOpLValue(const UnaryOperator *E) {
// __extension__ doesn't affect lvalue-ness.
if (E->getOpcode() == UnaryOperator::Extension)
return EmitLValue(E->getSubExpr());
assert(E->getOpcode() == UnaryOperator::Deref &&
"'*' is the only unary operator that produces an lvalue");
return LValue::MakeAddr(EmitExpr(E->getSubExpr()).getVal());
}
LValue CodeGenFunction::EmitStringLiteralLValue(const StringLiteral *E) {
assert(!E->isWide() && "FIXME: Wide strings not supported yet!");
const char *StrData = E->getStrData();
unsigned Len = E->getByteLength();
// FIXME: Can cache/reuse these within the module.
llvm::Constant *C=llvm::ConstantArray::get(std::string(StrData, StrData+Len));
// Create a global variable for this.
C = new llvm::GlobalVariable(C->getType(), true,
llvm::GlobalValue::InternalLinkage,
C, ".str", CurFn->getParent());
llvm::Constant *Zero = llvm::Constant::getNullValue(llvm::Type::Int32Ty);
llvm::Constant *Zeros[] = { Zero, Zero };
C = llvm::ConstantExpr::getGetElementPtr(C, Zeros, 2);
return LValue::MakeAddr(C);
}
LValue CodeGenFunction::EmitPreDefinedLValue(const PreDefinedExpr *E) {
std::string FunctionName(CurFuncDecl->getName());
std::string GlobalVarName;
switch (E->getIdentType()) {
default:
assert(0 && "unknown pre-defined ident type");
case PreDefinedExpr::Func:
GlobalVarName = "__func__.";
break;
case PreDefinedExpr::Function:
GlobalVarName = "__FUNCTION__.";
break;
case PreDefinedExpr::PrettyFunction:
// FIXME:: Demangle C++ method names
GlobalVarName = "__PRETTY_FUNCTION__.";
break;
}
GlobalVarName += CurFuncDecl->getName();
// FIXME: Can cache/reuse these within the module.
llvm::Constant *C=llvm::ConstantArray::get(FunctionName);
// Create a global variable for this.
C = new llvm::GlobalVariable(C->getType(), true,
llvm::GlobalValue::InternalLinkage,
C, GlobalVarName, CurFn->getParent());
llvm::Constant *Zero = llvm::Constant::getNullValue(llvm::Type::Int32Ty);
llvm::Constant *Zeros[] = { Zero, Zero };
C = llvm::ConstantExpr::getGetElementPtr(C, Zeros, 2);
return LValue::MakeAddr(C);
}
LValue CodeGenFunction::EmitArraySubscriptExpr(const ArraySubscriptExpr *E) {
// The index must always be a pointer or integer, neither of which is an
// aggregate. Emit it.
QualType IdxTy;
llvm::Value *Idx =
EmitExprWithUsualUnaryConversions(E->getIdx(), IdxTy).getVal();
// If the base is a vector type, then we are forming a vector element lvalue
// with this subscript.
if (E->getBase()->getType()->isVectorType()) {
// Emit the vector as an lvalue to get its address.
LValue Base = EmitLValue(E->getBase());
assert(Base.isSimple() && "Can only subscript lvalue vectors here!");
// FIXME: This should properly sign/zero/extend or truncate Idx to i32.
return LValue::MakeVectorElt(Base.getAddress(), Idx);
}
// At this point, the base must be a pointer or integer, neither of which are
// aggregates. Emit it.
QualType BaseTy;
llvm::Value *Base =
EmitExprWithUsualUnaryConversions(E->getBase(), BaseTy).getVal();
// Usually the base is the pointer type, but sometimes it is the index.
// Canonicalize to have the pointer as the base.
if (isa<llvm::PointerType>(Idx->getType())) {
std::swap(Base, Idx);
std::swap(BaseTy, IdxTy);
}
// The pointer is now the base. Extend or truncate the index type to 32 or
// 64-bits.
bool IdxSigned = IdxTy->isSignedIntegerType();
unsigned IdxBitwidth = cast<llvm::IntegerType>(Idx->getType())->getBitWidth();
if (IdxBitwidth != LLVMPointerWidth)
Idx = Builder.CreateIntCast(Idx, llvm::IntegerType::get(LLVMPointerWidth),
IdxSigned, "idxprom");
// We know that the pointer points to a type of the correct size, unless the
// size is a VLA.
if (!E->getType()->isConstantSizeType(getContext()))
assert(0 && "VLA idx not implemented");
return LValue::MakeAddr(Builder.CreateGEP(Base, Idx, "arrayidx"));
}
//===--------------------------------------------------------------------===//
// Expression Emission
//===--------------------------------------------------------------------===//
RValue CodeGenFunction::EmitExpr(const Expr *E) {
assert(E && "Null expression?");
switch (E->getStmtClass()) {
default:
fprintf(stderr, "Unimplemented expr!\n");
E->dump();
return RValue::get(llvm::UndefValue::get(llvm::Type::Int32Ty));
// l-values.
case Expr::DeclRefExprClass:
// DeclRef's of EnumConstantDecl's are simple rvalues.
if (const EnumConstantDecl *EC =
dyn_cast<EnumConstantDecl>(cast<DeclRefExpr>(E)->getDecl()))
return RValue::get(llvm::ConstantInt::get(EC->getInitVal()));
return EmitLoadOfLValue(E);
case Expr::ArraySubscriptExprClass:
return EmitArraySubscriptExprRV(cast<ArraySubscriptExpr>(E));
case Expr::PreDefinedExprClass:
case Expr::StringLiteralClass:
return RValue::get(EmitLValue(E).getAddress());
// Leaf expressions.
case Expr::IntegerLiteralClass:
return EmitIntegerLiteral(cast<IntegerLiteral>(E));
case Expr::FloatingLiteralClass:
return EmitFloatingLiteral(cast<FloatingLiteral>(E));
case Expr::CharacterLiteralClass:
return EmitCharacterLiteral(cast<CharacterLiteral>(E));
// Operators.
case Expr::ParenExprClass:
return EmitExpr(cast<ParenExpr>(E)->getSubExpr());
case Expr::UnaryOperatorClass:
return EmitUnaryOperator(cast<UnaryOperator>(E));
case Expr::SizeOfAlignOfTypeExprClass:
return EmitSizeAlignOf(cast<SizeOfAlignOfTypeExpr>(E)->getArgumentType(),
E->getType(),
cast<SizeOfAlignOfTypeExpr>(E)->isSizeOf());
case Expr::ImplicitCastExprClass:
return EmitCastExpr(cast<ImplicitCastExpr>(E)->getSubExpr(), E->getType());
case Expr::CastExprClass:
return EmitCastExpr(cast<CastExpr>(E)->getSubExpr(), E->getType());
case Expr::CallExprClass:
return EmitCallExpr(cast<CallExpr>(E));
case Expr::BinaryOperatorClass:
return EmitBinaryOperator(cast<BinaryOperator>(E));
case Expr::ConditionalOperatorClass:
return EmitConditionalOperator(cast<ConditionalOperator>(E));
}
}
RValue CodeGenFunction::EmitIntegerLiteral(const IntegerLiteral *E) {
return RValue::get(llvm::ConstantInt::get(E->getValue()));
}
RValue CodeGenFunction::EmitFloatingLiteral(const FloatingLiteral *E) {
return RValue::get(llvm::ConstantFP::get(ConvertType(E->getType()),
E->getValue()));
}
RValue CodeGenFunction::EmitCharacterLiteral(const CharacterLiteral *E) {
return RValue::get(llvm::ConstantInt::get(ConvertType(E->getType()),
E->getValue()));
}
RValue CodeGenFunction::EmitArraySubscriptExprRV(const ArraySubscriptExpr *E) {
// Emit subscript expressions in rvalue context's. For most cases, this just
// loads the lvalue formed by the subscript expr. However, we have to be
// careful, because the base of a vector subscript is occasionally an rvalue,
// so we can't get it as an lvalue.
if (!E->getBase()->getType()->isVectorType())
return EmitLoadOfLValue(E);
// Handle the vector case. The base must be a vector, the index must be an
// integer value.
QualType BaseTy, IdxTy;
llvm::Value *Base =
EmitExprWithUsualUnaryConversions(E->getBase(), BaseTy).getVal();
llvm::Value *Idx =
EmitExprWithUsualUnaryConversions(E->getIdx(), IdxTy).getVal();
// FIXME: Convert Idx to i32 type.
return RValue::get(Builder.CreateExtractElement(Base, Idx, "vecext"));
}
// EmitCastExpr - Emit code for an explicit or implicit cast. Implicit casts
// have to handle a more broad range of conversions than explicit casts, as they
// handle things like function to ptr-to-function decay etc.
RValue CodeGenFunction::EmitCastExpr(const Expr *Op, QualType DestTy) {
QualType SrcTy;
RValue Src = EmitExprWithUsualUnaryConversions(Op, SrcTy);
// If the destination is void, just evaluate the source.
if (DestTy->isVoidType())
return RValue::getAggregate(0);
return EmitConversion(Src, SrcTy, DestTy);
}
RValue CodeGenFunction::EmitCallExpr(const CallExpr *E) {
QualType CalleeTy;
llvm::Value *Callee =
EmitExprWithUsualUnaryConversions(E->getCallee(), CalleeTy).getVal();
// The callee type will always be a pointer to function type, get the function
// type.
CalleeTy = cast<PointerType>(CalleeTy.getCanonicalType())->getPointeeType();
// Get information about the argument types.
FunctionTypeProto::arg_type_iterator ArgTyIt = 0, ArgTyEnd = 0;
// Calling unprototyped functions provides no argument info.
if (const FunctionTypeProto *FTP = dyn_cast<FunctionTypeProto>(CalleeTy)) {
ArgTyIt = FTP->arg_type_begin();
ArgTyEnd = FTP->arg_type_end();
}
llvm::SmallVector<llvm::Value*, 16> Args;
// FIXME: Handle struct return.
for (unsigned i = 0, e = E->getNumArgs(); i != e; ++i) {
QualType ArgTy;
RValue ArgVal = EmitExprWithUsualUnaryConversions(E->getArg(i), ArgTy);
// If this argument has prototype information, convert it.
if (ArgTyIt != ArgTyEnd) {
ArgVal = EmitConversion(ArgVal, ArgTy, *ArgTyIt++);
} else {
// Otherwise, if passing through "..." or to a function with no prototype,
// perform the "default argument promotions" (C99 6.5.2.2p6), which
// includes the usual unary conversions, but also promotes float to
// double.
if (const BuiltinType *BT =
dyn_cast<BuiltinType>(ArgTy.getCanonicalType())) {
if (BT->getKind() == BuiltinType::Float)
ArgVal = RValue::get(Builder.CreateFPExt(ArgVal.getVal(),
llvm::Type::DoubleTy,"tmp"));
}
}
if (ArgVal.isScalar())
Args.push_back(ArgVal.getVal());
else // Pass by-address. FIXME: Set attribute bit on call.
Args.push_back(ArgVal.getAggregateAddr());
}
llvm::Value *V = Builder.CreateCall(Callee, &Args[0], &Args[0]+Args.size());
if (V->getType() != llvm::Type::VoidTy)
V->setName("call");
// FIXME: Struct return;
return RValue::get(V);
}
//===----------------------------------------------------------------------===//
// Unary Operator Emission
//===----------------------------------------------------------------------===//
RValue CodeGenFunction::EmitExprWithUsualUnaryConversions(const Expr *E,
QualType &ResTy) {
ResTy = E->getType().getCanonicalType();
if (isa<FunctionType>(ResTy)) { // C99 6.3.2.1p4
// Functions are promoted to their address.
ResTy = getContext().getPointerType(ResTy);
return RValue::get(EmitLValue(E).getAddress());
} else if (const ArrayType *ary = dyn_cast<ArrayType>(ResTy)) {
// C99 6.3.2.1p3
ResTy = getContext().getPointerType(ary->getElementType());
// FIXME: For now we assume that all source arrays map to LLVM arrays. This
// will not true when we add support for VLAs.
llvm::Value *V = EmitLValue(E).getAddress(); // Bitfields can't be arrays.
assert(isa<llvm::PointerType>(V->getType()) &&
isa<llvm::ArrayType>(cast<llvm::PointerType>(V->getType())
->getElementType()) &&
"Doesn't support VLAs yet!");
llvm::Constant *Idx0 = llvm::ConstantInt::get(llvm::Type::Int32Ty, 0);
return RValue::get(Builder.CreateGEP(V, Idx0, Idx0, "arraydecay"));
} else if (ResTy->isPromotableIntegerType()) { // C99 6.3.1.1p2
// FIXME: this probably isn't right, pending clarification from Steve.
llvm::Value *Val = EmitExpr(E).getVal();
// If the input is a signed integer, sign extend to the destination.
if (ResTy->isSignedIntegerType()) {
Val = Builder.CreateSExt(Val, LLVMIntTy, "promote");
} else {
// This handles unsigned types, including bool.
Val = Builder.CreateZExt(Val, LLVMIntTy, "promote");
}
ResTy = getContext().IntTy;
return RValue::get(Val);
}
// Otherwise, this is a float, double, int, struct, etc.
return EmitExpr(E);
}
RValue CodeGenFunction::EmitUnaryOperator(const UnaryOperator *E) {
switch (E->getOpcode()) {
default:
printf("Unimplemented unary expr!\n");
E->dump();
return RValue::get(llvm::UndefValue::get(llvm::Type::Int32Ty));
case UnaryOperator::PostInc:
case UnaryOperator::PostDec:
case UnaryOperator::PreInc :
case UnaryOperator::PreDec : return EmitUnaryIncDec(E);
case UnaryOperator::AddrOf : return EmitUnaryAddrOf(E);
case UnaryOperator::Deref : return EmitLoadOfLValue(E);
case UnaryOperator::Plus : return EmitUnaryPlus(E);
case UnaryOperator::Minus : return EmitUnaryMinus(E);
case UnaryOperator::Not : return EmitUnaryNot(E);
case UnaryOperator::LNot : return EmitUnaryLNot(E);
case UnaryOperator::SizeOf :
return EmitSizeAlignOf(E->getSubExpr()->getType(), E->getType(), true);
case UnaryOperator::AlignOf :
return EmitSizeAlignOf(E->getSubExpr()->getType(), E->getType(), false);
// FIXME: real/imag
case UnaryOperator::Extension: return EmitExpr(E->getSubExpr());
}
}
RValue CodeGenFunction::EmitUnaryIncDec(const UnaryOperator *E) {
LValue LV = EmitLValue(E->getSubExpr());
RValue InVal = EmitLoadOfLValue(LV, E->getSubExpr()->getType());
// We know the operand is real or pointer type, so it must be an LLVM scalar.
assert(InVal.isScalar() && "Unknown thing to increment");
llvm::Value *InV = InVal.getVal();
int AmountVal = 1;
if (E->getOpcode() == UnaryOperator::PreDec ||
E->getOpcode() == UnaryOperator::PostDec)
AmountVal = -1;
llvm::Value *NextVal;
if (isa<llvm::IntegerType>(InV->getType())) {
NextVal = llvm::ConstantInt::get(InV->getType(), AmountVal);
NextVal = Builder.CreateAdd(InV, NextVal, AmountVal == 1 ? "inc" : "dec");
} else if (InV->getType()->isFloatingPoint()) {
NextVal = llvm::ConstantFP::get(InV->getType(), AmountVal);
NextVal = Builder.CreateAdd(InV, NextVal, AmountVal == 1 ? "inc" : "dec");
} else {
// FIXME: This is not right for pointers to VLA types.
assert(isa<llvm::PointerType>(InV->getType()));
NextVal = llvm::ConstantInt::get(llvm::Type::Int32Ty, AmountVal);
NextVal = Builder.CreateGEP(InV, NextVal, AmountVal == 1 ? "inc" : "dec");
}
RValue NextValToStore = RValue::get(NextVal);
// Store the updated result through the lvalue.
EmitStoreThroughLValue(NextValToStore, LV, E->getSubExpr()->getType());
// If this is a postinc, return the value read from memory, otherwise use the
// updated value.
if (E->getOpcode() == UnaryOperator::PreDec ||
E->getOpcode() == UnaryOperator::PreInc)
return NextValToStore;
else
return InVal;
}
/// C99 6.5.3.2
RValue CodeGenFunction::EmitUnaryAddrOf(const UnaryOperator *E) {
// The address of the operand is just its lvalue. It cannot be a bitfield.
return RValue::get(EmitLValue(E->getSubExpr()).getAddress());
}
RValue CodeGenFunction::EmitUnaryPlus(const UnaryOperator *E) {
// Unary plus just performs promotions on its arithmetic operand.
QualType Ty;
return EmitExprWithUsualUnaryConversions(E->getSubExpr(), Ty);
}
RValue CodeGenFunction::EmitUnaryMinus(const UnaryOperator *E) {
// Unary minus performs promotions, then negates its arithmetic operand.
QualType Ty;
RValue V = EmitExprWithUsualUnaryConversions(E->getSubExpr(), Ty);
if (V.isScalar())
return RValue::get(Builder.CreateNeg(V.getVal(), "neg"));
assert(0 && "FIXME: This doesn't handle complex operands yet");
}
RValue CodeGenFunction::EmitUnaryNot(const UnaryOperator *E) {
// Unary not performs promotions, then complements its integer operand.
QualType Ty;
RValue V = EmitExprWithUsualUnaryConversions(E->getSubExpr(), Ty);
if (V.isScalar())
return RValue::get(Builder.CreateNot(V.getVal(), "neg"));
assert(0 && "FIXME: This doesn't handle integer complex operands yet (GNU)");
}
/// C99 6.5.3.3
RValue CodeGenFunction::EmitUnaryLNot(const UnaryOperator *E) {
// Compare operand to zero.
llvm::Value *BoolVal = EvaluateExprAsBool(E->getSubExpr());
// Invert value.
// TODO: Could dynamically modify easy computations here. For example, if
// the operand is an icmp ne, turn into icmp eq.
BoolVal = Builder.CreateNot(BoolVal, "lnot");
// ZExt result to int.
return RValue::get(Builder.CreateZExt(BoolVal, LLVMIntTy, "lnot.ext"));
}
/// EmitSizeAlignOf - Return the size or alignment of the 'TypeToSize' type as
/// an integer (RetType).
RValue CodeGenFunction::EmitSizeAlignOf(QualType TypeToSize,
QualType RetType, bool isSizeOf) {
/// FIXME: This doesn't handle VLAs yet!
std::pair<uint64_t, unsigned> Info =
getContext().getTypeInfo(TypeToSize, SourceLocation());
uint64_t Val = isSizeOf ? Info.first : Info.second;
Val /= 8; // Return size in bytes, not bits.
assert(RetType->isIntegerType() && "Result type must be an integer!");
unsigned ResultWidth = getContext().getTypeSize(RetType, SourceLocation());
return RValue::get(llvm::ConstantInt::get(llvm::APInt(ResultWidth, Val)));
}
//===--------------------------------------------------------------------===//
// Binary Operator Emission
//===--------------------------------------------------------------------===//
// FIXME describe.
QualType CodeGenFunction::
EmitUsualArithmeticConversions(const BinaryOperator *E, RValue &LHS,
RValue &RHS) {
QualType LHSType, RHSType;
LHS = EmitExprWithUsualUnaryConversions(E->getLHS(), LHSType);
RHS = EmitExprWithUsualUnaryConversions(E->getRHS(), RHSType);
// If both operands have the same source type, we're done already.
if (LHSType == RHSType) return LHSType;
// If either side is a non-arithmetic type (e.g. a pointer), we are done.
// The caller can deal with this (e.g. pointer + int).
if (!LHSType->isArithmeticType() || !RHSType->isArithmeticType())
return LHSType;
// At this point, we have two different arithmetic types.
// Handle complex types first (C99 6.3.1.8p1).
if (LHSType->isComplexType() || RHSType->isComplexType()) {
assert(0 && "FIXME: complex types unimp");
#if 0
// if we have an integer operand, the result is the complex type.
if (rhs->isIntegerType())
return lhs;
if (lhs->isIntegerType())
return rhs;
return Context.maxComplexType(lhs, rhs);
#endif
}
// If neither operand is complex, they must be scalars.
llvm::Value *LHSV = LHS.getVal();
llvm::Value *RHSV = RHS.getVal();
// If the LLVM types are already equal, then they only differed in sign, or it
// was something like char/signed char or double/long double.
if (LHSV->getType() == RHSV->getType())
return LHSType;
// Now handle "real" floating types (i.e. float, double, long double).
if (LHSType->isRealFloatingType() || RHSType->isRealFloatingType()) {
// if we have an integer operand, the result is the real floating type, and
// the integer converts to FP.
if (RHSType->isIntegerType()) {
// Promote the RHS to an FP type of the LHS, with the sign following the
// RHS.
if (RHSType->isSignedIntegerType())
RHS = RValue::get(Builder.CreateSIToFP(RHSV,LHSV->getType(),"promote"));
else
RHS = RValue::get(Builder.CreateUIToFP(RHSV,LHSV->getType(),"promote"));
return LHSType;
}
if (LHSType->isIntegerType()) {
// Promote the LHS to an FP type of the RHS, with the sign following the
// LHS.
if (LHSType->isSignedIntegerType())
LHS = RValue::get(Builder.CreateSIToFP(LHSV,RHSV->getType(),"promote"));
else
LHS = RValue::get(Builder.CreateUIToFP(LHSV,RHSV->getType(),"promote"));
return RHSType;
}
// Otherwise, they are two FP types. Promote the smaller operand to the
// bigger result.
QualType BiggerType = ASTContext::maxFloatingType(LHSType, RHSType);
if (BiggerType == LHSType)
RHS = RValue::get(Builder.CreateFPExt(RHSV, LHSV->getType(), "promote"));
else
LHS = RValue::get(Builder.CreateFPExt(LHSV, RHSV->getType(), "promote"));
return BiggerType;
}
// Finally, we have two integer types that are different according to C. Do
// a sign or zero extension if needed.
// Otherwise, one type is smaller than the other.
QualType ResTy = ASTContext::maxIntegerType(LHSType, RHSType);
if (LHSType == ResTy) {
if (RHSType->isSignedIntegerType())
RHS = RValue::get(Builder.CreateSExt(RHSV, LHSV->getType(), "promote"));
else
RHS = RValue::get(Builder.CreateZExt(RHSV, LHSV->getType(), "promote"));
} else {
assert(RHSType == ResTy && "Unknown conversion");
if (LHSType->isSignedIntegerType())
LHS = RValue::get(Builder.CreateSExt(LHSV, RHSV->getType(), "promote"));
else
LHS = RValue::get(Builder.CreateZExt(LHSV, RHSV->getType(), "promote"));
}
return ResTy;
}
/// EmitCompoundAssignmentOperands - Compound assignment operations (like +=)
/// are strange in that the result of the operation is not the same type as the
/// intermediate computation. This function emits the LHS and RHS operands of
/// the compound assignment, promoting them to their common computation type.
///
/// Since the LHS is an lvalue, and the result is stored back through it, we
/// return the lvalue as well as the LHS/RHS rvalues. On return, the LHS and
/// RHS values are both in the computation type for the operator.
void CodeGenFunction::
EmitCompoundAssignmentOperands(const CompoundAssignOperator *E,
LValue &LHSLV, RValue &LHS, RValue &RHS) {
LHSLV = EmitLValue(E->getLHS());
// Load the LHS and RHS operands.
QualType LHSTy = E->getLHS()->getType();
LHS = EmitLoadOfLValue(LHSLV, LHSTy);
QualType RHSTy;
RHS = EmitExprWithUsualUnaryConversions(E->getRHS(), RHSTy);
// Shift operands do the usual unary conversions, but do not do the binary
// conversions.
if (E->isShiftAssignOp()) {
// FIXME: This is broken. Implicit conversions should be made explicit,
// so that this goes away. This causes us to reload the LHS.
LHS = EmitExprWithUsualUnaryConversions(E->getLHS(), LHSTy);
}
// Convert the LHS and RHS to the common evaluation type.
LHS = EmitConversion(LHS, LHSTy, E->getComputationType());
RHS = EmitConversion(RHS, RHSTy, E->getComputationType());
}
/// EmitCompoundAssignmentResult - Given a result value in the computation type,
/// truncate it down to the actual result type, store it through the LHS lvalue,
/// and return it.
RValue CodeGenFunction::
EmitCompoundAssignmentResult(const CompoundAssignOperator *E,
LValue LHSLV, RValue ResV) {
// Truncate back to the destination type.
if (E->getComputationType() != E->getType())
ResV = EmitConversion(ResV, E->getComputationType(), E->getType());
// Store the result value into the LHS.
EmitStoreThroughLValue(ResV, LHSLV, E->getType());
// Return the result.
return ResV;
}
RValue CodeGenFunction::EmitBinaryOperator(const BinaryOperator *E) {
RValue LHS, RHS;
switch (E->getOpcode()) {
default:
fprintf(stderr, "Unimplemented binary expr!\n");
E->dump();
return RValue::get(llvm::UndefValue::get(llvm::Type::Int32Ty));
case BinaryOperator::Mul:
EmitUsualArithmeticConversions(E, LHS, RHS);
return EmitMul(LHS, RHS, E->getType());
case BinaryOperator::Div:
EmitUsualArithmeticConversions(E, LHS, RHS);
return EmitDiv(LHS, RHS, E->getType());
case BinaryOperator::Rem:
EmitUsualArithmeticConversions(E, LHS, RHS);
return EmitRem(LHS, RHS, E->getType());
case BinaryOperator::Add: {
QualType ExprTy = E->getType();
if (ExprTy->isPointerType()) {
Expr *LHSExpr = E->getLHS();
QualType LHSTy;
LHS = EmitExprWithUsualUnaryConversions(LHSExpr, LHSTy);
Expr *RHSExpr = E->getRHS();
QualType RHSTy;
RHS = EmitExprWithUsualUnaryConversions(RHSExpr, RHSTy);
return EmitPointerAdd(LHS, LHSTy, RHS, RHSTy, ExprTy);
} else {
EmitUsualArithmeticConversions(E, LHS, RHS);
return EmitAdd(LHS, RHS, ExprTy);
}
}
case BinaryOperator::Sub: {
QualType ExprTy = E->getType();
Expr *LHSExpr = E->getLHS();
if (LHSExpr->getType()->isPointerType()) {
QualType LHSTy;
LHS = EmitExprWithUsualUnaryConversions(LHSExpr, LHSTy);
Expr *RHSExpr = E->getRHS();
QualType RHSTy;
RHS = EmitExprWithUsualUnaryConversions(RHSExpr, RHSTy);
return EmitPointerSub(LHS, LHSTy, RHS, RHSTy, ExprTy);
} else {
EmitUsualArithmeticConversions(E, LHS, RHS);
return EmitSub(LHS, RHS, ExprTy);
}
}
case BinaryOperator::Shl:
EmitShiftOperands(E, LHS, RHS);
return EmitShl(LHS, RHS, E->getType());
case BinaryOperator::Shr:
EmitShiftOperands(E, LHS, RHS);
return EmitShr(LHS, RHS, E->getType());
case BinaryOperator::And:
EmitUsualArithmeticConversions(E, LHS, RHS);
return EmitAnd(LHS, RHS, E->getType());
case BinaryOperator::Xor:
EmitUsualArithmeticConversions(E, LHS, RHS);
return EmitXor(LHS, RHS, E->getType());
case BinaryOperator::Or :
EmitUsualArithmeticConversions(E, LHS, RHS);
return EmitOr(LHS, RHS, E->getType());
case BinaryOperator::LAnd: return EmitBinaryLAnd(E);
case BinaryOperator::LOr: return EmitBinaryLOr(E);
case BinaryOperator::LT:
return EmitBinaryCompare(E, llvm::ICmpInst::ICMP_ULT,
llvm::ICmpInst::ICMP_SLT,
llvm::FCmpInst::FCMP_OLT);
case BinaryOperator::GT:
return EmitBinaryCompare(E, llvm::ICmpInst::ICMP_UGT,
llvm::ICmpInst::ICMP_SGT,
llvm::FCmpInst::FCMP_OGT);
case BinaryOperator::LE:
return EmitBinaryCompare(E, llvm::ICmpInst::ICMP_ULE,
llvm::ICmpInst::ICMP_SLE,
llvm::FCmpInst::FCMP_OLE);
case BinaryOperator::GE:
return EmitBinaryCompare(E, llvm::ICmpInst::ICMP_UGE,
llvm::ICmpInst::ICMP_SGE,
llvm::FCmpInst::FCMP_OGE);
case BinaryOperator::EQ:
return EmitBinaryCompare(E, llvm::ICmpInst::ICMP_EQ,
llvm::ICmpInst::ICMP_EQ,
llvm::FCmpInst::FCMP_OEQ);
case BinaryOperator::NE:
return EmitBinaryCompare(E, llvm::ICmpInst::ICMP_NE,
llvm::ICmpInst::ICMP_NE,
llvm::FCmpInst::FCMP_UNE);
case BinaryOperator::Assign:
return EmitBinaryAssign(E);
case BinaryOperator::MulAssign: {
const CompoundAssignOperator *CAO = cast<CompoundAssignOperator>(E);
LValue LHSLV;
EmitCompoundAssignmentOperands(CAO, LHSLV, LHS, RHS);
LHS = EmitMul(LHS, RHS, CAO->getComputationType());
return EmitCompoundAssignmentResult(CAO, LHSLV, LHS);
}
case BinaryOperator::DivAssign: {
const CompoundAssignOperator *CAO = cast<CompoundAssignOperator>(E);
LValue LHSLV;
EmitCompoundAssignmentOperands(CAO, LHSLV, LHS, RHS);
LHS = EmitDiv(LHS, RHS, CAO->getComputationType());
return EmitCompoundAssignmentResult(CAO, LHSLV, LHS);
}
case BinaryOperator::RemAssign: {
const CompoundAssignOperator *CAO = cast<CompoundAssignOperator>(E);
LValue LHSLV;
EmitCompoundAssignmentOperands(CAO, LHSLV, LHS, RHS);
LHS = EmitRem(LHS, RHS, CAO->getComputationType());
return EmitCompoundAssignmentResult(CAO, LHSLV, LHS);
}
case BinaryOperator::AddAssign: {
const CompoundAssignOperator *CAO = cast<CompoundAssignOperator>(E);
LValue LHSLV;
EmitCompoundAssignmentOperands(CAO, LHSLV, LHS, RHS);
LHS = EmitAdd(LHS, RHS, CAO->getComputationType());
return EmitCompoundAssignmentResult(CAO, LHSLV, LHS);
}
case BinaryOperator::SubAssign: {
const CompoundAssignOperator *CAO = cast<CompoundAssignOperator>(E);
LValue LHSLV;
EmitCompoundAssignmentOperands(CAO, LHSLV, LHS, RHS);
LHS = EmitSub(LHS, RHS, CAO->getComputationType());
return EmitCompoundAssignmentResult(CAO, LHSLV, LHS);
}
case BinaryOperator::ShlAssign: {
const CompoundAssignOperator *CAO = cast<CompoundAssignOperator>(E);
LValue LHSLV;
EmitCompoundAssignmentOperands(CAO, LHSLV, LHS, RHS);
LHS = EmitShl(LHS, RHS, CAO->getComputationType());
return EmitCompoundAssignmentResult(CAO, LHSLV, LHS);
}
case BinaryOperator::ShrAssign: {
const CompoundAssignOperator *CAO = cast<CompoundAssignOperator>(E);
LValue LHSLV;
EmitCompoundAssignmentOperands(CAO, LHSLV, LHS, RHS);
LHS = EmitShr(LHS, RHS, CAO->getComputationType());
return EmitCompoundAssignmentResult(CAO, LHSLV, LHS);
}
case BinaryOperator::AndAssign: {
const CompoundAssignOperator *CAO = cast<CompoundAssignOperator>(E);
LValue LHSLV;
EmitCompoundAssignmentOperands(CAO, LHSLV, LHS, RHS);
LHS = EmitAnd(LHS, RHS, CAO->getComputationType());
return EmitCompoundAssignmentResult(CAO, LHSLV, LHS);
}
case BinaryOperator::OrAssign: {
const CompoundAssignOperator *CAO = cast<CompoundAssignOperator>(E);
LValue LHSLV;
EmitCompoundAssignmentOperands(CAO, LHSLV, LHS, RHS);
LHS = EmitOr(LHS, RHS, CAO->getComputationType());
return EmitCompoundAssignmentResult(CAO, LHSLV, LHS);
}
case BinaryOperator::XorAssign: {
const CompoundAssignOperator *CAO = cast<CompoundAssignOperator>(E);
LValue LHSLV;
EmitCompoundAssignmentOperands(CAO, LHSLV, LHS, RHS);
LHS = EmitXor(LHS, RHS, CAO->getComputationType());
return EmitCompoundAssignmentResult(CAO, LHSLV, LHS);
}
case BinaryOperator::Comma: return EmitBinaryComma(E);
}
}
RValue CodeGenFunction::EmitMul(RValue LHS, RValue RHS, QualType ResTy) {
if (LHS.isScalar())
return RValue::get(Builder.CreateMul(LHS.getVal(), RHS.getVal(), "mul"));
// Otherwise, this must be a complex number.
llvm::Value *LHSR, *LHSI, *RHSR, *RHSI;
EmitLoadOfComplex(LHS, LHSR, LHSI);
EmitLoadOfComplex(RHS, RHSR, RHSI);
llvm::Value *ResRl = Builder.CreateMul(LHSR, RHSR, "mul.rl");
llvm::Value *ResRr = Builder.CreateMul(LHSI, RHSI, "mul.rr");
llvm::Value *ResR = Builder.CreateSub(ResRl, ResRr, "mul.r");
llvm::Value *ResIl = Builder.CreateMul(LHSI, RHSR, "mul.il");
llvm::Value *ResIr = Builder.CreateMul(LHSR, RHSI, "mul.ir");
llvm::Value *ResI = Builder.CreateAdd(ResIl, ResIr, "mul.i");
llvm::Value *Res = CreateTempAlloca(ConvertType(ResTy));
EmitStoreOfComplex(ResR, ResI, Res);
return RValue::getAggregate(Res);
}
RValue CodeGenFunction::EmitDiv(RValue LHS, RValue RHS, QualType ResTy) {
if (LHS.isScalar()) {
llvm::Value *RV;
if (LHS.getVal()->getType()->isFloatingPoint())
RV = Builder.CreateFDiv(LHS.getVal(), RHS.getVal(), "div");
else if (ResTy->isUnsignedIntegerType())
RV = Builder.CreateUDiv(LHS.getVal(), RHS.getVal(), "div");
else
RV = Builder.CreateSDiv(LHS.getVal(), RHS.getVal(), "div");
return RValue::get(RV);
}
assert(0 && "FIXME: This doesn't handle complex operands yet");
}
RValue CodeGenFunction::EmitRem(RValue LHS, RValue RHS, QualType ResTy) {
if (LHS.isScalar()) {
llvm::Value *RV;
// Rem in C can't be a floating point type: C99 6.5.5p2.
if (ResTy->isUnsignedIntegerType())
RV = Builder.CreateURem(LHS.getVal(), RHS.getVal(), "rem");
else
RV = Builder.CreateSRem(LHS.getVal(), RHS.getVal(), "rem");
return RValue::get(RV);
}
assert(0 && "FIXME: This doesn't handle complex operands yet");
}
RValue CodeGenFunction::EmitAdd(RValue LHS, RValue RHS, QualType ResTy) {
if (LHS.isScalar())
return RValue::get(Builder.CreateAdd(LHS.getVal(), RHS.getVal(), "add"));
// Otherwise, this must be a complex number.
llvm::Value *LHSR, *LHSI, *RHSR, *RHSI;
EmitLoadOfComplex(LHS, LHSR, LHSI);
EmitLoadOfComplex(RHS, RHSR, RHSI);
llvm::Value *ResR = Builder.CreateAdd(LHSR, RHSR, "add.r");
llvm::Value *ResI = Builder.CreateAdd(LHSI, RHSI, "add.i");
llvm::Value *Res = CreateTempAlloca(ConvertType(ResTy));
EmitStoreOfComplex(ResR, ResI, Res);
return RValue::getAggregate(Res);
}
RValue CodeGenFunction::EmitPointerAdd(RValue LHS, QualType LHSTy,
RValue RHS, QualType RHSTy,
QualType ResTy) {
llvm::Value *LHSValue = LHS.getVal();
llvm::Value *RHSValue = RHS.getVal();
if (LHSTy->isPointerType()) {
// pointer + int
return RValue::get(Builder.CreateGEP(LHSValue, RHSValue, "add.ptr"));
} else {
// int + pointer
return RValue::get(Builder.CreateGEP(RHSValue, LHSValue, "add.ptr"));
}
}
RValue CodeGenFunction::EmitSub(RValue LHS, RValue RHS, QualType ResTy) {
if (LHS.isScalar())
return RValue::get(Builder.CreateSub(LHS.getVal(), RHS.getVal(), "sub"));
assert(0 && "FIXME: This doesn't handle complex operands yet");
}
RValue CodeGenFunction::EmitPointerSub(RValue LHS, QualType LHSTy,
RValue RHS, QualType RHSTy,
QualType ResTy) {
llvm::Value *LHSValue = LHS.getVal();
llvm::Value *RHSValue = RHS.getVal();
if (const PointerType *RHSPtrType =
dyn_cast<PointerType>(RHSTy.getTypePtr())) {
// pointer - pointer
const PointerType *LHSPtrType = cast<PointerType>(LHSTy.getTypePtr());
QualType LHSElementType = LHSPtrType->getPointeeType();
assert(LHSElementType == RHSPtrType->getPointeeType() &&
"can't subtract pointers with differing element types");
uint64_t ElementSize = getContext().getTypeSize(LHSElementType,
SourceLocation()) / 8;
const llvm::Type *ResultType = ConvertType(ResTy);
llvm::Value *CastLHS = Builder.CreatePtrToInt(LHSValue, ResultType,
"sub.ptr.lhs.cast");
llvm::Value *CastRHS = Builder.CreatePtrToInt(RHSValue, ResultType,
"sub.ptr.rhs.cast");
llvm::Value *BytesBetween = Builder.CreateSub(CastLHS, CastRHS,
"sub.ptr.sub");
// HACK: LLVM doesn't have an divide instruction that 'knows' there is no
// remainder. As such, we handle common power-of-two cases here to generate
// better code.
if (llvm::isPowerOf2_64(ElementSize)) {
llvm::Value *ShAmt =
llvm::ConstantInt::get(ResultType, llvm::Log2_64(ElementSize));
return RValue::get(Builder.CreateAShr(BytesBetween, ShAmt,"sub.ptr.shr"));
} else {
// Otherwise, do a full sdiv.
llvm::Value *BytesPerElement =
llvm::ConstantInt::get(ResultType, ElementSize);
return RValue::get(Builder.CreateSDiv(BytesBetween, BytesPerElement,
"sub.ptr.div"));
}
} else {
// pointer - int
llvm::Value *NegatedRHS = Builder.CreateNeg(RHSValue, "sub.ptr.neg");
return RValue::get(Builder.CreateGEP(LHSValue, NegatedRHS, "sub.ptr"));
}
}
void CodeGenFunction::EmitShiftOperands(const BinaryOperator *E,
RValue &LHS, RValue &RHS) {
// For shifts, integer promotions are performed, but the usual arithmetic
// conversions are not. The LHS and RHS need not have the same type.
QualType ResTy;
LHS = EmitExprWithUsualUnaryConversions(E->getLHS(), ResTy);
RHS = EmitExprWithUsualUnaryConversions(E->getRHS(), ResTy);
}
RValue CodeGenFunction::EmitShl(RValue LHSV, RValue RHSV, QualType ResTy) {
llvm::Value *LHS = LHSV.getVal(), *RHS = RHSV.getVal();
// LLVM requires the LHS and RHS to be the same type, promote or truncate the
// RHS to the same size as the LHS.
if (LHS->getType() != RHS->getType())
RHS = Builder.CreateIntCast(RHS, LHS->getType(), false, "sh_prom");
return RValue::get(Builder.CreateShl(LHS, RHS, "shl"));
}
RValue CodeGenFunction::EmitShr(RValue LHSV, RValue RHSV, QualType ResTy) {
llvm::Value *LHS = LHSV.getVal(), *RHS = RHSV.getVal();
// LLVM requires the LHS and RHS to be the same type, promote or truncate the
// RHS to the same size as the LHS.
if (LHS->getType() != RHS->getType())
RHS = Builder.CreateIntCast(RHS, LHS->getType(), false, "sh_prom");
if (ResTy->isUnsignedIntegerType())
return RValue::get(Builder.CreateLShr(LHS, RHS, "shr"));
else
return RValue::get(Builder.CreateAShr(LHS, RHS, "shr"));
}
RValue CodeGenFunction::EmitBinaryCompare(const BinaryOperator *E,
unsigned UICmpOpc, unsigned SICmpOpc,
unsigned FCmpOpc) {
RValue LHS, RHS;
EmitUsualArithmeticConversions(E, LHS, RHS);
llvm::Value *Result;
if (LHS.isScalar()) {
if (LHS.getVal()->getType()->isFloatingPoint()) {
Result = Builder.CreateFCmp((llvm::FCmpInst::Predicate)FCmpOpc,
LHS.getVal(), RHS.getVal(), "cmp");
} else if (E->getLHS()->getType()->isUnsignedIntegerType()) {
// FIXME: This check isn't right for "unsigned short < int" where ushort
// promotes to int and does a signed compare.
Result = Builder.CreateICmp((llvm::ICmpInst::Predicate)UICmpOpc,
LHS.getVal(), RHS.getVal(), "cmp");
} else {
// Signed integers and pointers.
Result = Builder.CreateICmp((llvm::ICmpInst::Predicate)SICmpOpc,
LHS.getVal(), RHS.getVal(), "cmp");
}
} else {
// Struct/union/complex
llvm::Value *LHSR, *LHSI, *RHSR, *RHSI, *ResultR, *ResultI;
EmitLoadOfComplex(LHS, LHSR, LHSI);
EmitLoadOfComplex(RHS, RHSR, RHSI);
// FIXME: need to consider _Complex over integers too!
ResultR = Builder.CreateFCmp((llvm::FCmpInst::Predicate)FCmpOpc,
LHSR, RHSR, "cmp.r");
ResultI = Builder.CreateFCmp((llvm::FCmpInst::Predicate)FCmpOpc,
LHSI, RHSI, "cmp.i");
if (BinaryOperator::EQ == E->getOpcode()) {
Result = Builder.CreateAnd(ResultR, ResultI, "and.ri");
} else if (BinaryOperator::NE == E->getOpcode()) {
Result = Builder.CreateOr(ResultR, ResultI, "or.ri");
} else {
assert(0 && "Complex comparison other than == or != ?");
}
}
// ZExt result to int.
return RValue::get(Builder.CreateZExt(Result, LLVMIntTy, "cmp.ext"));
}
RValue CodeGenFunction::EmitAnd(RValue LHS, RValue RHS, QualType ResTy) {
if (LHS.isScalar())
return RValue::get(Builder.CreateAnd(LHS.getVal(), RHS.getVal(), "and"));
assert(0 && "FIXME: This doesn't handle complex integer operands yet (GNU)");
}
RValue CodeGenFunction::EmitXor(RValue LHS, RValue RHS, QualType ResTy) {
if (LHS.isScalar())
return RValue::get(Builder.CreateXor(LHS.getVal(), RHS.getVal(), "xor"));
assert(0 && "FIXME: This doesn't handle complex integer operands yet (GNU)");
}
RValue CodeGenFunction::EmitOr(RValue LHS, RValue RHS, QualType ResTy) {
if (LHS.isScalar())
return RValue::get(Builder.CreateOr(LHS.getVal(), RHS.getVal(), "or"));
assert(0 && "FIXME: This doesn't handle complex integer operands yet (GNU)");
}
RValue CodeGenFunction::EmitBinaryLAnd(const BinaryOperator *E) {
llvm::Value *LHSCond = EvaluateExprAsBool(E->getLHS());
llvm::BasicBlock *ContBlock = new llvm::BasicBlock("land_cont");
llvm::BasicBlock *RHSBlock = new llvm::BasicBlock("land_rhs");
llvm::BasicBlock *OrigBlock = Builder.GetInsertBlock();
Builder.CreateCondBr(LHSCond, RHSBlock, ContBlock);
EmitBlock(RHSBlock);
llvm::Value *RHSCond = EvaluateExprAsBool(E->getRHS());
// Reaquire the RHS block, as there may be subblocks inserted.
RHSBlock = Builder.GetInsertBlock();
EmitBlock(ContBlock);
// Create a PHI node. If we just evaluted the LHS condition, the result is
// false. If we evaluated both, the result is the RHS condition.
llvm::PHINode *PN = Builder.CreatePHI(llvm::Type::Int1Ty, "land");
PN->reserveOperandSpace(2);
PN->addIncoming(llvm::ConstantInt::getFalse(), OrigBlock);
PN->addIncoming(RHSCond, RHSBlock);
// ZExt result to int.
return RValue::get(Builder.CreateZExt(PN, LLVMIntTy, "land.ext"));
}
RValue CodeGenFunction::EmitBinaryLOr(const BinaryOperator *E) {
llvm::Value *LHSCond = EvaluateExprAsBool(E->getLHS());
llvm::BasicBlock *ContBlock = new llvm::BasicBlock("lor_cont");
llvm::BasicBlock *RHSBlock = new llvm::BasicBlock("lor_rhs");
llvm::BasicBlock *OrigBlock = Builder.GetInsertBlock();
Builder.CreateCondBr(LHSCond, ContBlock, RHSBlock);
EmitBlock(RHSBlock);
llvm::Value *RHSCond = EvaluateExprAsBool(E->getRHS());
// Reaquire the RHS block, as there may be subblocks inserted.
RHSBlock = Builder.GetInsertBlock();
EmitBlock(ContBlock);
// Create a PHI node. If we just evaluted the LHS condition, the result is
// true. If we evaluated both, the result is the RHS condition.
llvm::PHINode *PN = Builder.CreatePHI(llvm::Type::Int1Ty, "lor");
PN->reserveOperandSpace(2);
PN->addIncoming(llvm::ConstantInt::getTrue(), OrigBlock);
PN->addIncoming(RHSCond, RHSBlock);
// ZExt result to int.
return RValue::get(Builder.CreateZExt(PN, LLVMIntTy, "lor.ext"));
}
RValue CodeGenFunction::EmitBinaryAssign(const BinaryOperator *E) {
LValue LHS = EmitLValue(E->getLHS());
QualType RHSTy;
RValue RHS = EmitExprWithUsualUnaryConversions(E->getRHS(), RHSTy);
// Convert the RHS to the type of the LHS.
RHS = EmitConversion(RHS, RHSTy, E->getType());
// Store the value into the LHS.
EmitStoreThroughLValue(RHS, LHS, E->getType());
// Return the converted RHS.
return RHS;
}
RValue CodeGenFunction::EmitBinaryComma(const BinaryOperator *E) {
EmitExpr(E->getLHS());
return EmitExpr(E->getRHS());
}
RValue CodeGenFunction::EmitConditionalOperator(const ConditionalOperator *E) {
llvm::BasicBlock *LHSBlock = new llvm::BasicBlock("cond.?");
llvm::BasicBlock *RHSBlock = new llvm::BasicBlock("cond.:");
llvm::BasicBlock *ContBlock = new llvm::BasicBlock("cond.cont");
llvm::Value *Cond = EvaluateExprAsBool(E->getCond());
Builder.CreateCondBr(Cond, LHSBlock, RHSBlock);
// FIXME: Implement this for aggregate values.
// FIXME: LHS & RHS need the "usual arithmetic conversions" but
// that's not possible with the current design.
EmitBlock(LHSBlock);
QualType LHSTy;
llvm::Value *LHSValue = E->getLHS() ? // GNU extension
EmitExprWithUsualUnaryConversions(E->getLHS(), LHSTy).getVal() :
Cond;
Builder.CreateBr(ContBlock);
LHSBlock = Builder.GetInsertBlock();
EmitBlock(RHSBlock);
QualType RHSTy;
llvm::Value *RHSValue =
EmitExprWithUsualUnaryConversions(E->getRHS(), RHSTy).getVal();
Builder.CreateBr(ContBlock);
RHSBlock = Builder.GetInsertBlock();
const llvm::Type *LHSType = LHSValue->getType();
assert(LHSType == RHSValue->getType() && "?: LHS & RHS must have same type");
EmitBlock(ContBlock);
llvm::PHINode *PN = Builder.CreatePHI(LHSType, "cond");
PN->reserveOperandSpace(2);
PN->addIncoming(LHSValue, LHSBlock);
PN->addIncoming(RHSValue, RHSBlock);
return RValue::get(PN);
}
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