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llvm-project/clang/lib/CodeGen/TargetInfo.cpp

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//===---- TargetInfo.cpp - Encapsulate target details -----------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// These classes wrap the information about a call or function
// definition used to handle ABI compliancy.
//
//===----------------------------------------------------------------------===//
#include "TargetInfo.h"
#include "ABIInfo.h"
#include "CGCXXABI.h"
#include "CodeGenFunction.h"
#include "clang/AST/RecordLayout.h"
#include "clang/Frontend/CodeGenOptions.h"
#include "llvm/ADT/Triple.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/Type.h"
#include "llvm/Support/raw_ostream.h"
using namespace clang;
using namespace CodeGen;
static void AssignToArrayRange(CodeGen::CGBuilderTy &Builder,
llvm::Value *Array,
llvm::Value *Value,
unsigned FirstIndex,
unsigned LastIndex) {
// Alternatively, we could emit this as a loop in the source.
for (unsigned I = FirstIndex; I <= LastIndex; ++I) {
llvm::Value *Cell = Builder.CreateConstInBoundsGEP1_32(Array, I);
Builder.CreateStore(Value, Cell);
}
}
static bool isAggregateTypeForABI(QualType T) {
return !CodeGenFunction::hasScalarEvaluationKind(T) ||
T->isMemberFunctionPointerType();
}
ABIInfo::~ABIInfo() {}
static bool isRecordReturnIndirect(const RecordType *RT, CodeGen::CodeGenTypes &CGT) {
const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl());
if (!RD)
return false;
return CGT.CGM.getCXXABI().isReturnTypeIndirect(RD);
}
static bool isRecordReturnIndirect(QualType T, CodeGen::CodeGenTypes &CGT) {
const RecordType *RT = T->getAs<RecordType>();
if (!RT)
return false;
return isRecordReturnIndirect(RT, CGT);
}
static CGCXXABI::RecordArgABI getRecordArgABI(const RecordType *RT,
CodeGen::CodeGenTypes &CGT) {
const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl());
if (!RD)
return CGCXXABI::RAA_Default;
return CGT.CGM.getCXXABI().getRecordArgABI(RD);
}
static CGCXXABI::RecordArgABI getRecordArgABI(QualType T,
CodeGen::CodeGenTypes &CGT) {
const RecordType *RT = T->getAs<RecordType>();
if (!RT)
return CGCXXABI::RAA_Default;
return getRecordArgABI(RT, CGT);
}
ASTContext &ABIInfo::getContext() const {
return CGT.getContext();
}
llvm::LLVMContext &ABIInfo::getVMContext() const {
return CGT.getLLVMContext();
}
const llvm::DataLayout &ABIInfo::getDataLayout() const {
return CGT.getDataLayout();
}
const TargetInfo &ABIInfo::getTarget() const {
return CGT.getTarget();
}
void ABIArgInfo::dump() const {
raw_ostream &OS = llvm::errs();
OS << "(ABIArgInfo Kind=";
switch (TheKind) {
case Direct:
OS << "Direct Type=";
if (llvm::Type *Ty = getCoerceToType())
Ty->print(OS);
else
OS << "null";
break;
case Extend:
OS << "Extend";
break;
case Ignore:
OS << "Ignore";
break;
case Indirect:
OS << "Indirect Align=" << getIndirectAlign()
<< " ByVal=" << getIndirectByVal()
<< " Realign=" << getIndirectRealign();
break;
case Expand:
OS << "Expand";
break;
}
OS << ")\n";
}
TargetCodeGenInfo::~TargetCodeGenInfo() { delete Info; }
// If someone can figure out a general rule for this, that would be great.
// It's probably just doomed to be platform-dependent, though.
unsigned TargetCodeGenInfo::getSizeOfUnwindException() const {
// Verified for:
// x86-64 FreeBSD, Linux, Darwin
// x86-32 FreeBSD, Linux, Darwin
// PowerPC Linux, Darwin
// ARM Darwin (*not* EABI)
// AArch64 Linux
return 32;
}
bool TargetCodeGenInfo::isNoProtoCallVariadic(const CallArgList &args,
const FunctionNoProtoType *fnType) const {
// The following conventions are known to require this to be false:
// x86_stdcall
// MIPS
// For everything else, we just prefer false unless we opt out.
return false;
}
void
TargetCodeGenInfo::getDependentLibraryOption(llvm::StringRef Lib,
llvm::SmallString<24> &Opt) const {
// This assumes the user is passing a library name like "rt" instead of a
// filename like "librt.a/so", and that they don't care whether it's static or
// dynamic.
Opt = "-l";
Opt += Lib;
}
static bool isEmptyRecord(ASTContext &Context, QualType T, bool AllowArrays);
/// isEmptyField - Return true iff a the field is "empty", that is it
/// is an unnamed bit-field or an (array of) empty record(s).
static bool isEmptyField(ASTContext &Context, const FieldDecl *FD,
bool AllowArrays) {
if (FD->isUnnamedBitfield())
return true;
QualType FT = FD->getType();
// Constant arrays of empty records count as empty, strip them off.
// Constant arrays of zero length always count as empty.
if (AllowArrays)
while (const ConstantArrayType *AT = Context.getAsConstantArrayType(FT)) {
if (AT->getSize() == 0)
return true;
FT = AT->getElementType();
}
const RecordType *RT = FT->getAs<RecordType>();
if (!RT)
return false;
// C++ record fields are never empty, at least in the Itanium ABI.
//
// FIXME: We should use a predicate for whether this behavior is true in the
// current ABI.
if (isa<CXXRecordDecl>(RT->getDecl()))
return false;
return isEmptyRecord(Context, FT, AllowArrays);
}
/// isEmptyRecord - Return true iff a structure contains only empty
/// fields. Note that a structure with a flexible array member is not
/// considered empty.
static bool isEmptyRecord(ASTContext &Context, QualType T, bool AllowArrays) {
const RecordType *RT = T->getAs<RecordType>();
if (!RT)
return 0;
const RecordDecl *RD = RT->getDecl();
if (RD->hasFlexibleArrayMember())
return false;
// If this is a C++ record, check the bases first.
if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD))
for (CXXRecordDecl::base_class_const_iterator i = CXXRD->bases_begin(),
e = CXXRD->bases_end(); i != e; ++i)
if (!isEmptyRecord(Context, i->getType(), true))
return false;
for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end();
i != e; ++i)
if (!isEmptyField(Context, *i, AllowArrays))
return false;
return true;
}
/// isSingleElementStruct - Determine if a structure is a "single
/// element struct", i.e. it has exactly one non-empty field or
/// exactly one field which is itself a single element
/// struct. Structures with flexible array members are never
/// considered single element structs.
///
/// \return The field declaration for the single non-empty field, if
/// it exists.
static const Type *isSingleElementStruct(QualType T, ASTContext &Context) {
const RecordType *RT = T->getAsStructureType();
if (!RT)
return 0;
const RecordDecl *RD = RT->getDecl();
if (RD->hasFlexibleArrayMember())
return 0;
const Type *Found = 0;
// If this is a C++ record, check the bases first.
if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD)) {
for (CXXRecordDecl::base_class_const_iterator i = CXXRD->bases_begin(),
e = CXXRD->bases_end(); i != e; ++i) {
// Ignore empty records.
if (isEmptyRecord(Context, i->getType(), true))
continue;
// If we already found an element then this isn't a single-element struct.
if (Found)
return 0;
// If this is non-empty and not a single element struct, the composite
// cannot be a single element struct.
Found = isSingleElementStruct(i->getType(), Context);
if (!Found)
return 0;
}
}
// Check for single element.
for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end();
i != e; ++i) {
const FieldDecl *FD = *i;
QualType FT = FD->getType();
// Ignore empty fields.
if (isEmptyField(Context, FD, true))
continue;
// If we already found an element then this isn't a single-element
// struct.
if (Found)
return 0;
// Treat single element arrays as the element.
while (const ConstantArrayType *AT = Context.getAsConstantArrayType(FT)) {
if (AT->getSize().getZExtValue() != 1)
break;
FT = AT->getElementType();
}
if (!isAggregateTypeForABI(FT)) {
Found = FT.getTypePtr();
} else {
Found = isSingleElementStruct(FT, Context);
if (!Found)
return 0;
}
}
// We don't consider a struct a single-element struct if it has
// padding beyond the element type.
if (Found && Context.getTypeSize(Found) != Context.getTypeSize(T))
return 0;
return Found;
}
static bool is32Or64BitBasicType(QualType Ty, ASTContext &Context) {
// Treat complex types as the element type.
if (const ComplexType *CTy = Ty->getAs<ComplexType>())
Ty = CTy->getElementType();
// Check for a type which we know has a simple scalar argument-passing
// convention without any padding. (We're specifically looking for 32
// and 64-bit integer and integer-equivalents, float, and double.)
if (!Ty->getAs<BuiltinType>() && !Ty->hasPointerRepresentation() &&
!Ty->isEnumeralType() && !Ty->isBlockPointerType())
return false;
uint64_t Size = Context.getTypeSize(Ty);
return Size == 32 || Size == 64;
}
/// canExpandIndirectArgument - Test whether an argument type which is to be
/// passed indirectly (on the stack) would have the equivalent layout if it was
/// expanded into separate arguments. If so, we prefer to do the latter to avoid
/// inhibiting optimizations.
///
// FIXME: This predicate is missing many cases, currently it just follows
// llvm-gcc (checks that all fields are 32-bit or 64-bit primitive types). We
// should probably make this smarter, or better yet make the LLVM backend
// capable of handling it.
static bool canExpandIndirectArgument(QualType Ty, ASTContext &Context) {
// We can only expand structure types.
const RecordType *RT = Ty->getAs<RecordType>();
if (!RT)
return false;
// We can only expand (C) structures.
//
// FIXME: This needs to be generalized to handle classes as well.
const RecordDecl *RD = RT->getDecl();
if (!RD->isStruct() || isa<CXXRecordDecl>(RD))
return false;
uint64_t Size = 0;
for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end();
i != e; ++i) {
const FieldDecl *FD = *i;
if (!is32Or64BitBasicType(FD->getType(), Context))
return false;
// FIXME: Reject bit-fields wholesale; there are two problems, we don't know
// how to expand them yet, and the predicate for telling if a bitfield still
// counts as "basic" is more complicated than what we were doing previously.
if (FD->isBitField())
return false;
Size += Context.getTypeSize(FD->getType());
}
// Make sure there are not any holes in the struct.
if (Size != Context.getTypeSize(Ty))
return false;
return true;
}
namespace {
/// DefaultABIInfo - The default implementation for ABI specific
/// details. This implementation provides information which results in
/// self-consistent and sensible LLVM IR generation, but does not
/// conform to any particular ABI.
class DefaultABIInfo : public ABIInfo {
public:
DefaultABIInfo(CodeGen::CodeGenTypes &CGT) : ABIInfo(CGT) {}
ABIArgInfo classifyReturnType(QualType RetTy) const;
ABIArgInfo classifyArgumentType(QualType RetTy) const;
virtual void computeInfo(CGFunctionInfo &FI) const {
FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end();
it != ie; ++it)
it->info = classifyArgumentType(it->type);
}
virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
CodeGenFunction &CGF) const;
};
class DefaultTargetCodeGenInfo : public TargetCodeGenInfo {
public:
DefaultTargetCodeGenInfo(CodeGen::CodeGenTypes &CGT)
: TargetCodeGenInfo(new DefaultABIInfo(CGT)) {}
};
llvm::Value *DefaultABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
CodeGenFunction &CGF) const {
return 0;
}
ABIArgInfo DefaultABIInfo::classifyArgumentType(QualType Ty) const {
if (isAggregateTypeForABI(Ty)) {
// Records with non trivial destructors/constructors should not be passed
// by value.
if (isRecordReturnIndirect(Ty, CGT))
return ABIArgInfo::getIndirect(0, /*ByVal=*/false);
return ABIArgInfo::getIndirect(0);
}
// Treat an enum type as its underlying type.
if (const EnumType *EnumTy = Ty->getAs<EnumType>())
Ty = EnumTy->getDecl()->getIntegerType();
return (Ty->isPromotableIntegerType() ?
ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
}
ABIArgInfo DefaultABIInfo::classifyReturnType(QualType RetTy) const {
if (RetTy->isVoidType())
return ABIArgInfo::getIgnore();
if (isAggregateTypeForABI(RetTy))
return ABIArgInfo::getIndirect(0);
// Treat an enum type as its underlying type.
if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
RetTy = EnumTy->getDecl()->getIntegerType();
return (RetTy->isPromotableIntegerType() ?
ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
}
//===----------------------------------------------------------------------===//
// le32/PNaCl bitcode ABI Implementation
//
// This is a simplified version of the x86_32 ABI. Arguments and return values
// are always passed on the stack.
//===----------------------------------------------------------------------===//
class PNaClABIInfo : public ABIInfo {
public:
PNaClABIInfo(CodeGen::CodeGenTypes &CGT) : ABIInfo(CGT) {}
ABIArgInfo classifyReturnType(QualType RetTy) const;
ABIArgInfo classifyArgumentType(QualType RetTy) const;
virtual void computeInfo(CGFunctionInfo &FI) const;
virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
CodeGenFunction &CGF) const;
};
class PNaClTargetCodeGenInfo : public TargetCodeGenInfo {
public:
PNaClTargetCodeGenInfo(CodeGen::CodeGenTypes &CGT)
: TargetCodeGenInfo(new PNaClABIInfo(CGT)) {}
};
void PNaClABIInfo::computeInfo(CGFunctionInfo &FI) const {
FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end();
it != ie; ++it)
it->info = classifyArgumentType(it->type);
}
llvm::Value *PNaClABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
CodeGenFunction &CGF) const {
return 0;
}
/// \brief Classify argument of given type \p Ty.
ABIArgInfo PNaClABIInfo::classifyArgumentType(QualType Ty) const {
if (isAggregateTypeForABI(Ty)) {
if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, CGT))
return ABIArgInfo::getIndirect(0, RAA == CGCXXABI::RAA_DirectInMemory);
return ABIArgInfo::getIndirect(0);
} else if (const EnumType *EnumTy = Ty->getAs<EnumType>()) {
// Treat an enum type as its underlying type.
Ty = EnumTy->getDecl()->getIntegerType();
} else if (Ty->isFloatingType()) {
// Floating-point types don't go inreg.
return ABIArgInfo::getDirect();
}
return (Ty->isPromotableIntegerType() ?
ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
}
ABIArgInfo PNaClABIInfo::classifyReturnType(QualType RetTy) const {
if (RetTy->isVoidType())
return ABIArgInfo::getIgnore();
// In the PNaCl ABI we always return records/structures on the stack.
if (isAggregateTypeForABI(RetTy))
return ABIArgInfo::getIndirect(0);
// Treat an enum type as its underlying type.
if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
RetTy = EnumTy->getDecl()->getIntegerType();
return (RetTy->isPromotableIntegerType() ?
ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
}
/// IsX86_MMXType - Return true if this is an MMX type.
bool IsX86_MMXType(llvm::Type *IRType) {
// Return true if the type is an MMX type <2 x i32>, <4 x i16>, or <8 x i8>.
return IRType->isVectorTy() && IRType->getPrimitiveSizeInBits() == 64 &&
cast<llvm::VectorType>(IRType)->getElementType()->isIntegerTy() &&
IRType->getScalarSizeInBits() != 64;
}
static llvm::Type* X86AdjustInlineAsmType(CodeGen::CodeGenFunction &CGF,
StringRef Constraint,
llvm::Type* Ty) {
if ((Constraint == "y" || Constraint == "&y") && Ty->isVectorTy()) {
if (cast<llvm::VectorType>(Ty)->getBitWidth() != 64) {
// Invalid MMX constraint
return 0;
}
return llvm::Type::getX86_MMXTy(CGF.getLLVMContext());
}
// No operation needed
return Ty;
}
//===----------------------------------------------------------------------===//
// X86-32 ABI Implementation
//===----------------------------------------------------------------------===//
/// X86_32ABIInfo - The X86-32 ABI information.
class X86_32ABIInfo : public ABIInfo {
enum Class {
Integer,
Float
};
static const unsigned MinABIStackAlignInBytes = 4;
bool IsDarwinVectorABI;
bool IsSmallStructInRegABI;
bool IsWin32StructABI;
unsigned DefaultNumRegisterParameters;
static bool isRegisterSize(unsigned Size) {
return (Size == 8 || Size == 16 || Size == 32 || Size == 64);
}
static bool shouldReturnTypeInRegister(QualType Ty, ASTContext &Context,
unsigned callingConvention);
/// getIndirectResult - Give a source type \arg Ty, return a suitable result
/// such that the argument will be passed in memory.
ABIArgInfo getIndirectResult(QualType Ty, bool ByVal,
unsigned &FreeRegs) const;
/// \brief Return the alignment to use for the given type on the stack.
unsigned getTypeStackAlignInBytes(QualType Ty, unsigned Align) const;
Class classify(QualType Ty) const;
ABIArgInfo classifyReturnType(QualType RetTy,
unsigned callingConvention) const;
ABIArgInfo classifyArgumentType(QualType RetTy, unsigned &FreeRegs,
bool IsFastCall) const;
bool shouldUseInReg(QualType Ty, unsigned &FreeRegs,
bool IsFastCall, bool &NeedsPadding) const;
public:
virtual void computeInfo(CGFunctionInfo &FI) const;
virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
CodeGenFunction &CGF) const;
X86_32ABIInfo(CodeGen::CodeGenTypes &CGT, bool d, bool p, bool w,
unsigned r)
: ABIInfo(CGT), IsDarwinVectorABI(d), IsSmallStructInRegABI(p),
IsWin32StructABI(w), DefaultNumRegisterParameters(r) {}
};
class X86_32TargetCodeGenInfo : public TargetCodeGenInfo {
public:
X86_32TargetCodeGenInfo(CodeGen::CodeGenTypes &CGT,
bool d, bool p, bool w, unsigned r)
:TargetCodeGenInfo(new X86_32ABIInfo(CGT, d, p, w, r)) {}
static bool isStructReturnInRegABI(
const llvm::Triple &Triple, const CodeGenOptions &Opts);
void SetTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
CodeGen::CodeGenModule &CGM) const;
int getDwarfEHStackPointer(CodeGen::CodeGenModule &CGM) const {
// Darwin uses different dwarf register numbers for EH.
if (CGM.getTarget().getTriple().isOSDarwin()) return 5;
return 4;
}
bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
llvm::Value *Address) const;
llvm::Type* adjustInlineAsmType(CodeGen::CodeGenFunction &CGF,
StringRef Constraint,
llvm::Type* Ty) const {
return X86AdjustInlineAsmType(CGF, Constraint, Ty);
}
};
}
/// shouldReturnTypeInRegister - Determine if the given type should be
/// passed in a register (for the Darwin ABI).
bool X86_32ABIInfo::shouldReturnTypeInRegister(QualType Ty,
ASTContext &Context,
unsigned callingConvention) {
uint64_t Size = Context.getTypeSize(Ty);
// Type must be register sized.
if (!isRegisterSize(Size))
return false;
if (Ty->isVectorType()) {
// 64- and 128- bit vectors inside structures are not returned in
// registers.
if (Size == 64 || Size == 128)
return false;
return true;
}
// If this is a builtin, pointer, enum, complex type, member pointer, or
// member function pointer it is ok.
if (Ty->getAs<BuiltinType>() || Ty->hasPointerRepresentation() ||
Ty->isAnyComplexType() || Ty->isEnumeralType() ||
Ty->isBlockPointerType() || Ty->isMemberPointerType())
return true;
// Arrays are treated like records.
if (const ConstantArrayType *AT = Context.getAsConstantArrayType(Ty))
return shouldReturnTypeInRegister(AT->getElementType(), Context,
callingConvention);
// Otherwise, it must be a record type.
const RecordType *RT = Ty->getAs<RecordType>();
if (!RT) return false;
// FIXME: Traverse bases here too.
// For thiscall conventions, structures will never be returned in
// a register. This is for compatibility with the MSVC ABI
if (callingConvention == llvm::CallingConv::X86_ThisCall &&
RT->isStructureType()) {
return false;
}
// Structure types are passed in register if all fields would be
// passed in a register.
for (RecordDecl::field_iterator i = RT->getDecl()->field_begin(),
e = RT->getDecl()->field_end(); i != e; ++i) {
const FieldDecl *FD = *i;
// Empty fields are ignored.
if (isEmptyField(Context, FD, true))
continue;
// Check fields recursively.
if (!shouldReturnTypeInRegister(FD->getType(), Context,
callingConvention))
return false;
}
return true;
}
ABIArgInfo X86_32ABIInfo::classifyReturnType(QualType RetTy,
unsigned callingConvention) const {
if (RetTy->isVoidType())
return ABIArgInfo::getIgnore();
if (const VectorType *VT = RetTy->getAs<VectorType>()) {
// On Darwin, some vectors are returned in registers.
if (IsDarwinVectorABI) {
uint64_t Size = getContext().getTypeSize(RetTy);
// 128-bit vectors are a special case; they are returned in
// registers and we need to make sure to pick a type the LLVM
// backend will like.
if (Size == 128)
return ABIArgInfo::getDirect(llvm::VectorType::get(
llvm::Type::getInt64Ty(getVMContext()), 2));
// Always return in register if it fits in a general purpose
// register, or if it is 64 bits and has a single element.
if ((Size == 8 || Size == 16 || Size == 32) ||
(Size == 64 && VT->getNumElements() == 1))
return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(),
Size));
return ABIArgInfo::getIndirect(0);
}
return ABIArgInfo::getDirect();
}
if (isAggregateTypeForABI(RetTy)) {
if (const RecordType *RT = RetTy->getAs<RecordType>()) {
if (isRecordReturnIndirect(RT, CGT))
return ABIArgInfo::getIndirect(0, /*ByVal=*/false);
// Structures with flexible arrays are always indirect.
if (RT->getDecl()->hasFlexibleArrayMember())
return ABIArgInfo::getIndirect(0);
}
// If specified, structs and unions are always indirect.
if (!IsSmallStructInRegABI && !RetTy->isAnyComplexType())
return ABIArgInfo::getIndirect(0);
// Small structures which are register sized are generally returned
// in a register.
if (X86_32ABIInfo::shouldReturnTypeInRegister(RetTy, getContext(),
callingConvention)) {
uint64_t Size = getContext().getTypeSize(RetTy);
// As a special-case, if the struct is a "single-element" struct, and
// the field is of type "float" or "double", return it in a
// floating-point register. (MSVC does not apply this special case.)
// We apply a similar transformation for pointer types to improve the
// quality of the generated IR.
if (const Type *SeltTy = isSingleElementStruct(RetTy, getContext()))
if ((!IsWin32StructABI && SeltTy->isRealFloatingType())
|| SeltTy->hasPointerRepresentation())
return ABIArgInfo::getDirect(CGT.ConvertType(QualType(SeltTy, 0)));
// FIXME: We should be able to narrow this integer in cases with dead
// padding.
return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(),Size));
}
return ABIArgInfo::getIndirect(0);
}
// Treat an enum type as its underlying type.
if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
RetTy = EnumTy->getDecl()->getIntegerType();
return (RetTy->isPromotableIntegerType() ?
ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
}
static bool isSSEVectorType(ASTContext &Context, QualType Ty) {
return Ty->getAs<VectorType>() && Context.getTypeSize(Ty) == 128;
}
static bool isRecordWithSSEVectorType(ASTContext &Context, QualType Ty) {
const RecordType *RT = Ty->getAs<RecordType>();
if (!RT)
return 0;
const RecordDecl *RD = RT->getDecl();
// If this is a C++ record, check the bases first.
if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD))
for (CXXRecordDecl::base_class_const_iterator i = CXXRD->bases_begin(),
e = CXXRD->bases_end(); i != e; ++i)
if (!isRecordWithSSEVectorType(Context, i->getType()))
return false;
for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end();
i != e; ++i) {
QualType FT = i->getType();
if (isSSEVectorType(Context, FT))
return true;
if (isRecordWithSSEVectorType(Context, FT))
return true;
}
return false;
}
unsigned X86_32ABIInfo::getTypeStackAlignInBytes(QualType Ty,
unsigned Align) const {
// Otherwise, if the alignment is less than or equal to the minimum ABI
// alignment, just use the default; the backend will handle this.
if (Align <= MinABIStackAlignInBytes)
return 0; // Use default alignment.
// On non-Darwin, the stack type alignment is always 4.
if (!IsDarwinVectorABI) {
// Set explicit alignment, since we may need to realign the top.
return MinABIStackAlignInBytes;
}
// Otherwise, if the type contains an SSE vector type, the alignment is 16.
if (Align >= 16 && (isSSEVectorType(getContext(), Ty) ||
isRecordWithSSEVectorType(getContext(), Ty)))
return 16;
return MinABIStackAlignInBytes;
}
ABIArgInfo X86_32ABIInfo::getIndirectResult(QualType Ty, bool ByVal,
unsigned &FreeRegs) const {
if (!ByVal) {
if (FreeRegs) {
--FreeRegs; // Non byval indirects just use one pointer.
return ABIArgInfo::getIndirectInReg(0, false);
}
return ABIArgInfo::getIndirect(0, false);
}
// Compute the byval alignment.
unsigned TypeAlign = getContext().getTypeAlign(Ty) / 8;
unsigned StackAlign = getTypeStackAlignInBytes(Ty, TypeAlign);
if (StackAlign == 0)
return ABIArgInfo::getIndirect(4);
// If the stack alignment is less than the type alignment, realign the
// argument.
if (StackAlign < TypeAlign)
return ABIArgInfo::getIndirect(StackAlign, /*ByVal=*/true,
/*Realign=*/true);
return ABIArgInfo::getIndirect(StackAlign);
}
X86_32ABIInfo::Class X86_32ABIInfo::classify(QualType Ty) const {
const Type *T = isSingleElementStruct(Ty, getContext());
if (!T)
T = Ty.getTypePtr();
if (const BuiltinType *BT = T->getAs<BuiltinType>()) {
BuiltinType::Kind K = BT->getKind();
if (K == BuiltinType::Float || K == BuiltinType::Double)
return Float;
}
return Integer;
}
bool X86_32ABIInfo::shouldUseInReg(QualType Ty, unsigned &FreeRegs,
bool IsFastCall, bool &NeedsPadding) const {
NeedsPadding = false;
Class C = classify(Ty);
if (C == Float)
return false;
unsigned Size = getContext().getTypeSize(Ty);
unsigned SizeInRegs = (Size + 31) / 32;
if (SizeInRegs == 0)
return false;
if (SizeInRegs > FreeRegs) {
FreeRegs = 0;
return false;
}
FreeRegs -= SizeInRegs;
if (IsFastCall) {
if (Size > 32)
return false;
if (Ty->isIntegralOrEnumerationType())
return true;
if (Ty->isPointerType())
return true;
if (Ty->isReferenceType())
return true;
if (FreeRegs)
NeedsPadding = true;
return false;
}
return true;
}
ABIArgInfo X86_32ABIInfo::classifyArgumentType(QualType Ty,
unsigned &FreeRegs,
bool IsFastCall) const {
// FIXME: Set alignment on indirect arguments.
if (isAggregateTypeForABI(Ty)) {
if (const RecordType *RT = Ty->getAs<RecordType>()) {
if (IsWin32StructABI)
return getIndirectResult(Ty, true, FreeRegs);
if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(RT, CGT))
return getIndirectResult(Ty, RAA == CGCXXABI::RAA_DirectInMemory, FreeRegs);
// Structures with flexible arrays are always indirect.
if (RT->getDecl()->hasFlexibleArrayMember())
return getIndirectResult(Ty, true, FreeRegs);
}
// Ignore empty structs/unions.
if (isEmptyRecord(getContext(), Ty, true))
return ABIArgInfo::getIgnore();
llvm::LLVMContext &LLVMContext = getVMContext();
llvm::IntegerType *Int32 = llvm::Type::getInt32Ty(LLVMContext);
bool NeedsPadding;
if (shouldUseInReg(Ty, FreeRegs, IsFastCall, NeedsPadding)) {
unsigned SizeInRegs = (getContext().getTypeSize(Ty) + 31) / 32;
SmallVector<llvm::Type*, 3> Elements(SizeInRegs, Int32);
llvm::Type *Result = llvm::StructType::get(LLVMContext, Elements);
return ABIArgInfo::getDirectInReg(Result);
}
llvm::IntegerType *PaddingType = NeedsPadding ? Int32 : 0;
// Expand small (<= 128-bit) record types when we know that the stack layout
// of those arguments will match the struct. This is important because the
// LLVM backend isn't smart enough to remove byval, which inhibits many
// optimizations.
if (getContext().getTypeSize(Ty) <= 4*32 &&
canExpandIndirectArgument(Ty, getContext()))
return ABIArgInfo::getExpandWithPadding(IsFastCall, PaddingType);
return getIndirectResult(Ty, true, FreeRegs);
}
if (const VectorType *VT = Ty->getAs<VectorType>()) {
// On Darwin, some vectors are passed in memory, we handle this by passing
// it as an i8/i16/i32/i64.
if (IsDarwinVectorABI) {
uint64_t Size = getContext().getTypeSize(Ty);
if ((Size == 8 || Size == 16 || Size == 32) ||
(Size == 64 && VT->getNumElements() == 1))
return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(),
Size));
}
if (IsX86_MMXType(CGT.ConvertType(Ty)))
return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(), 64));
return ABIArgInfo::getDirect();
}
if (const EnumType *EnumTy = Ty->getAs<EnumType>())
Ty = EnumTy->getDecl()->getIntegerType();
bool NeedsPadding;
bool InReg = shouldUseInReg(Ty, FreeRegs, IsFastCall, NeedsPadding);
if (Ty->isPromotableIntegerType()) {
if (InReg)
return ABIArgInfo::getExtendInReg();
return ABIArgInfo::getExtend();
}
if (InReg)
return ABIArgInfo::getDirectInReg();
return ABIArgInfo::getDirect();
}
void X86_32ABIInfo::computeInfo(CGFunctionInfo &FI) const {
FI.getReturnInfo() = classifyReturnType(FI.getReturnType(),
FI.getCallingConvention());
unsigned CC = FI.getCallingConvention();
bool IsFastCall = CC == llvm::CallingConv::X86_FastCall;
unsigned FreeRegs;
if (IsFastCall)
FreeRegs = 2;
else if (FI.getHasRegParm())
FreeRegs = FI.getRegParm();
else
FreeRegs = DefaultNumRegisterParameters;
// If the return value is indirect, then the hidden argument is consuming one
// integer register.
if (FI.getReturnInfo().isIndirect() && FreeRegs) {
--FreeRegs;
ABIArgInfo &Old = FI.getReturnInfo();
Old = ABIArgInfo::getIndirectInReg(Old.getIndirectAlign(),
Old.getIndirectByVal(),
Old.getIndirectRealign());
}
for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end();
it != ie; ++it)
it->info = classifyArgumentType(it->type, FreeRegs, IsFastCall);
}
llvm::Value *X86_32ABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
CodeGenFunction &CGF) const {
llvm::Type *BPP = CGF.Int8PtrPtrTy;
CGBuilderTy &Builder = CGF.Builder;
llvm::Value *VAListAddrAsBPP = Builder.CreateBitCast(VAListAddr, BPP,
"ap");
llvm::Value *Addr = Builder.CreateLoad(VAListAddrAsBPP, "ap.cur");
// Compute if the address needs to be aligned
unsigned Align = CGF.getContext().getTypeAlignInChars(Ty).getQuantity();
Align = getTypeStackAlignInBytes(Ty, Align);
Align = std::max(Align, 4U);
if (Align > 4) {
// addr = (addr + align - 1) & -align;
llvm::Value *Offset =
llvm::ConstantInt::get(CGF.Int32Ty, Align - 1);
Addr = CGF.Builder.CreateGEP(Addr, Offset);
llvm::Value *AsInt = CGF.Builder.CreatePtrToInt(Addr,
CGF.Int32Ty);
llvm::Value *Mask = llvm::ConstantInt::get(CGF.Int32Ty, -Align);
Addr = CGF.Builder.CreateIntToPtr(CGF.Builder.CreateAnd(AsInt, Mask),
Addr->getType(),
"ap.cur.aligned");
}
llvm::Type *PTy =
llvm::PointerType::getUnqual(CGF.ConvertType(Ty));
llvm::Value *AddrTyped = Builder.CreateBitCast(Addr, PTy);
uint64_t Offset =
llvm::RoundUpToAlignment(CGF.getContext().getTypeSize(Ty) / 8, Align);
llvm::Value *NextAddr =
Builder.CreateGEP(Addr, llvm::ConstantInt::get(CGF.Int32Ty, Offset),
"ap.next");
Builder.CreateStore(NextAddr, VAListAddrAsBPP);
return AddrTyped;
}
void X86_32TargetCodeGenInfo::SetTargetAttributes(const Decl *D,
llvm::GlobalValue *GV,
CodeGen::CodeGenModule &CGM) const {
if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
if (FD->hasAttr<X86ForceAlignArgPointerAttr>()) {
// Get the LLVM function.
llvm::Function *Fn = cast<llvm::Function>(GV);
// Now add the 'alignstack' attribute with a value of 16.
llvm::AttrBuilder B;
B.addStackAlignmentAttr(16);
Fn->addAttributes(llvm::AttributeSet::FunctionIndex,
llvm::AttributeSet::get(CGM.getLLVMContext(),
llvm::AttributeSet::FunctionIndex,
B));
}
}
}
bool X86_32TargetCodeGenInfo::initDwarfEHRegSizeTable(
CodeGen::CodeGenFunction &CGF,
llvm::Value *Address) const {
CodeGen::CGBuilderTy &Builder = CGF.Builder;
llvm::Value *Four8 = llvm::ConstantInt::get(CGF.Int8Ty, 4);
// 0-7 are the eight integer registers; the order is different
// on Darwin (for EH), but the range is the same.
// 8 is %eip.
AssignToArrayRange(Builder, Address, Four8, 0, 8);
if (CGF.CGM.getTarget().getTriple().isOSDarwin()) {
// 12-16 are st(0..4). Not sure why we stop at 4.
// These have size 16, which is sizeof(long double) on
// platforms with 8-byte alignment for that type.
llvm::Value *Sixteen8 = llvm::ConstantInt::get(CGF.Int8Ty, 16);
AssignToArrayRange(Builder, Address, Sixteen8, 12, 16);
} else {
// 9 is %eflags, which doesn't get a size on Darwin for some
// reason.
Builder.CreateStore(Four8, Builder.CreateConstInBoundsGEP1_32(Address, 9));
// 11-16 are st(0..5). Not sure why we stop at 5.
// These have size 12, which is sizeof(long double) on
// platforms with 4-byte alignment for that type.
llvm::Value *Twelve8 = llvm::ConstantInt::get(CGF.Int8Ty, 12);
AssignToArrayRange(Builder, Address, Twelve8, 11, 16);
}
return false;
}
//===----------------------------------------------------------------------===//
// X86-64 ABI Implementation
//===----------------------------------------------------------------------===//
namespace {
/// X86_64ABIInfo - The X86_64 ABI information.
class X86_64ABIInfo : public ABIInfo {
enum Class {
Integer = 0,
SSE,
SSEUp,
X87,
X87Up,
ComplexX87,
NoClass,
Memory
};
/// merge - Implement the X86_64 ABI merging algorithm.
///
/// Merge an accumulating classification \arg Accum with a field
/// classification \arg Field.
///
/// \param Accum - The accumulating classification. This should
/// always be either NoClass or the result of a previous merge
/// call. In addition, this should never be Memory (the caller
/// should just return Memory for the aggregate).
static Class merge(Class Accum, Class Field);
/// postMerge - Implement the X86_64 ABI post merging algorithm.
///
/// Post merger cleanup, reduces a malformed Hi and Lo pair to
/// final MEMORY or SSE classes when necessary.
///
/// \param AggregateSize - The size of the current aggregate in
/// the classification process.
///
/// \param Lo - The classification for the parts of the type
/// residing in the low word of the containing object.
///
/// \param Hi - The classification for the parts of the type
/// residing in the higher words of the containing object.
///
void postMerge(unsigned AggregateSize, Class &Lo, Class &Hi) const;
/// classify - Determine the x86_64 register classes in which the
/// given type T should be passed.
///
/// \param Lo - The classification for the parts of the type
/// residing in the low word of the containing object.
///
/// \param Hi - The classification for the parts of the type
/// residing in the high word of the containing object.
///
/// \param OffsetBase - The bit offset of this type in the
/// containing object. Some parameters are classified different
/// depending on whether they straddle an eightbyte boundary.
///
/// \param isNamedArg - Whether the argument in question is a "named"
/// argument, as used in AMD64-ABI 3.5.7.
///
/// If a word is unused its result will be NoClass; if a type should
/// be passed in Memory then at least the classification of \arg Lo
/// will be Memory.
///
/// The \arg Lo class will be NoClass iff the argument is ignored.
///
/// If the \arg Lo class is ComplexX87, then the \arg Hi class will
/// also be ComplexX87.
void classify(QualType T, uint64_t OffsetBase, Class &Lo, Class &Hi,
bool isNamedArg) const;
llvm::Type *GetByteVectorType(QualType Ty) const;
llvm::Type *GetSSETypeAtOffset(llvm::Type *IRType,
unsigned IROffset, QualType SourceTy,
unsigned SourceOffset) const;
llvm::Type *GetINTEGERTypeAtOffset(llvm::Type *IRType,
unsigned IROffset, QualType SourceTy,
unsigned SourceOffset) const;
/// getIndirectResult - Give a source type \arg Ty, return a suitable result
/// such that the argument will be returned in memory.
ABIArgInfo getIndirectReturnResult(QualType Ty) const;
/// getIndirectResult - Give a source type \arg Ty, return a suitable result
/// such that the argument will be passed in memory.
///
/// \param freeIntRegs - The number of free integer registers remaining
/// available.
ABIArgInfo getIndirectResult(QualType Ty, unsigned freeIntRegs) const;
ABIArgInfo classifyReturnType(QualType RetTy) const;
ABIArgInfo classifyArgumentType(QualType Ty,
unsigned freeIntRegs,
unsigned &neededInt,
unsigned &neededSSE,
bool isNamedArg) const;
bool IsIllegalVectorType(QualType Ty) const;
/// The 0.98 ABI revision clarified a lot of ambiguities,
/// unfortunately in ways that were not always consistent with
/// certain previous compilers. In particular, platforms which
/// required strict binary compatibility with older versions of GCC
/// may need to exempt themselves.
bool honorsRevision0_98() const {
return !getTarget().getTriple().isOSDarwin();
}
bool HasAVX;
// Some ABIs (e.g. X32 ABI and Native Client OS) use 32 bit pointers on
// 64-bit hardware.
bool Has64BitPointers;
public:
X86_64ABIInfo(CodeGen::CodeGenTypes &CGT, bool hasavx) :
ABIInfo(CGT), HasAVX(hasavx),
Has64BitPointers(CGT.getDataLayout().getPointerSize(0) == 8) {
}
bool isPassedUsingAVXType(QualType type) const {
unsigned neededInt, neededSSE;
// The freeIntRegs argument doesn't matter here.
ABIArgInfo info = classifyArgumentType(type, 0, neededInt, neededSSE,
/*isNamedArg*/true);
if (info.isDirect()) {
llvm::Type *ty = info.getCoerceToType();
if (llvm::VectorType *vectorTy = dyn_cast_or_null<llvm::VectorType>(ty))
return (vectorTy->getBitWidth() > 128);
}
return false;
}
virtual void computeInfo(CGFunctionInfo &FI) const;
virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
CodeGenFunction &CGF) const;
};
/// WinX86_64ABIInfo - The Windows X86_64 ABI information.
class WinX86_64ABIInfo : public ABIInfo {
ABIArgInfo classify(QualType Ty, bool IsReturnType) const;
public:
WinX86_64ABIInfo(CodeGen::CodeGenTypes &CGT) : ABIInfo(CGT) {}
virtual void computeInfo(CGFunctionInfo &FI) const;
virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
CodeGenFunction &CGF) const;
};
class X86_64TargetCodeGenInfo : public TargetCodeGenInfo {
public:
X86_64TargetCodeGenInfo(CodeGen::CodeGenTypes &CGT, bool HasAVX)
: TargetCodeGenInfo(new X86_64ABIInfo(CGT, HasAVX)) {}
const X86_64ABIInfo &getABIInfo() const {
return static_cast<const X86_64ABIInfo&>(TargetCodeGenInfo::getABIInfo());
}
int getDwarfEHStackPointer(CodeGen::CodeGenModule &CGM) const {
return 7;
}
bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
llvm::Value *Address) const {
llvm::Value *Eight8 = llvm::ConstantInt::get(CGF.Int8Ty, 8);
// 0-15 are the 16 integer registers.
// 16 is %rip.
AssignToArrayRange(CGF.Builder, Address, Eight8, 0, 16);
return false;
}
llvm::Type* adjustInlineAsmType(CodeGen::CodeGenFunction &CGF,
StringRef Constraint,
llvm::Type* Ty) const {
return X86AdjustInlineAsmType(CGF, Constraint, Ty);
}
bool isNoProtoCallVariadic(const CallArgList &args,
const FunctionNoProtoType *fnType) const {
// The default CC on x86-64 sets %al to the number of SSA
// registers used, and GCC sets this when calling an unprototyped
// function, so we override the default behavior. However, don't do
// that when AVX types are involved: the ABI explicitly states it is
// undefined, and it doesn't work in practice because of how the ABI
// defines varargs anyway.
if (fnType->getCallConv() == CC_Default || fnType->getCallConv() == CC_C) {
bool HasAVXType = false;
for (CallArgList::const_iterator
it = args.begin(), ie = args.end(); it != ie; ++it) {
if (getABIInfo().isPassedUsingAVXType(it->Ty)) {
HasAVXType = true;
break;
}
}
if (!HasAVXType)
return true;
}
return TargetCodeGenInfo::isNoProtoCallVariadic(args, fnType);
}
};
static std::string qualifyWindowsLibrary(llvm::StringRef Lib) {
// If the argument does not end in .lib, automatically add the suffix. This
// matches the behavior of MSVC.
std::string ArgStr = Lib;
if (Lib.size() <= 4 ||
Lib.substr(Lib.size() - 4).compare_lower(".lib") != 0) {
ArgStr += ".lib";
}
return ArgStr;
}
class WinX86_32TargetCodeGenInfo : public X86_32TargetCodeGenInfo {
public:
WinX86_32TargetCodeGenInfo(CodeGen::CodeGenTypes &CGT,
bool d, bool p, bool w, unsigned RegParms)
: X86_32TargetCodeGenInfo(CGT, d, p, w, RegParms) {}
void getDependentLibraryOption(llvm::StringRef Lib,
llvm::SmallString<24> &Opt) const {
Opt = "/DEFAULTLIB:";
Opt += qualifyWindowsLibrary(Lib);
}
void getDetectMismatchOption(llvm::StringRef Name,
llvm::StringRef Value,
llvm::SmallString<32> &Opt) const {
Opt = "/FAILIFMISMATCH:\"" + Name.str() + "=" + Value.str() + "\"";
}
};
class WinX86_64TargetCodeGenInfo : public TargetCodeGenInfo {
public:
WinX86_64TargetCodeGenInfo(CodeGen::CodeGenTypes &CGT)
: TargetCodeGenInfo(new WinX86_64ABIInfo(CGT)) {}
int getDwarfEHStackPointer(CodeGen::CodeGenModule &CGM) const {
return 7;
}
bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
llvm::Value *Address) const {
llvm::Value *Eight8 = llvm::ConstantInt::get(CGF.Int8Ty, 8);
// 0-15 are the 16 integer registers.
// 16 is %rip.
AssignToArrayRange(CGF.Builder, Address, Eight8, 0, 16);
return false;
}
void getDependentLibraryOption(llvm::StringRef Lib,
llvm::SmallString<24> &Opt) const {
Opt = "/DEFAULTLIB:";
Opt += qualifyWindowsLibrary(Lib);
}
void getDetectMismatchOption(llvm::StringRef Name,
llvm::StringRef Value,
llvm::SmallString<32> &Opt) const {
Opt = "/FAILIFMISMATCH:\"" + Name.str() + "=" + Value.str() + "\"";
}
};
}
void X86_64ABIInfo::postMerge(unsigned AggregateSize, Class &Lo,
Class &Hi) const {
// AMD64-ABI 3.2.3p2: Rule 5. Then a post merger cleanup is done:
//
// (a) If one of the classes is Memory, the whole argument is passed in
// memory.
//
// (b) If X87UP is not preceded by X87, the whole argument is passed in
// memory.
//
// (c) If the size of the aggregate exceeds two eightbytes and the first
// eightbyte isn't SSE or any other eightbyte isn't SSEUP, the whole
// argument is passed in memory. NOTE: This is necessary to keep the
// ABI working for processors that don't support the __m256 type.
//
// (d) If SSEUP is not preceded by SSE or SSEUP, it is converted to SSE.
//
// Some of these are enforced by the merging logic. Others can arise
// only with unions; for example:
// union { _Complex double; unsigned; }
//
// Note that clauses (b) and (c) were added in 0.98.
//
if (Hi == Memory)
Lo = Memory;
if (Hi == X87Up && Lo != X87 && honorsRevision0_98())
Lo = Memory;
if (AggregateSize > 128 && (Lo != SSE || Hi != SSEUp))
Lo = Memory;
if (Hi == SSEUp && Lo != SSE)
Hi = SSE;
}
X86_64ABIInfo::Class X86_64ABIInfo::merge(Class Accum, Class Field) {
// AMD64-ABI 3.2.3p2: Rule 4. Each field of an object is
// classified recursively so that always two fields are
// considered. The resulting class is calculated according to
// the classes of the fields in the eightbyte:
//
// (a) If both classes are equal, this is the resulting class.
//
// (b) If one of the classes is NO_CLASS, the resulting class is
// the other class.
//
// (c) If one of the classes is MEMORY, the result is the MEMORY
// class.
//
// (d) If one of the classes is INTEGER, the result is the
// INTEGER.
//
// (e) If one of the classes is X87, X87UP, COMPLEX_X87 class,
// MEMORY is used as class.
//
// (f) Otherwise class SSE is used.
// Accum should never be memory (we should have returned) or
// ComplexX87 (because this cannot be passed in a structure).
assert((Accum != Memory && Accum != ComplexX87) &&
"Invalid accumulated classification during merge.");
if (Accum == Field || Field == NoClass)
return Accum;
if (Field == Memory)
return Memory;
if (Accum == NoClass)
return Field;
if (Accum == Integer || Field == Integer)
return Integer;
if (Field == X87 || Field == X87Up || Field == ComplexX87 ||
Accum == X87 || Accum == X87Up)
return Memory;
return SSE;
}
void X86_64ABIInfo::classify(QualType Ty, uint64_t OffsetBase,
Class &Lo, Class &Hi, bool isNamedArg) const {
// FIXME: This code can be simplified by introducing a simple value class for
// Class pairs with appropriate constructor methods for the various
// situations.
// FIXME: Some of the split computations are wrong; unaligned vectors
// shouldn't be passed in registers for example, so there is no chance they
// can straddle an eightbyte. Verify & simplify.
Lo = Hi = NoClass;
Class &Current = OffsetBase < 64 ? Lo : Hi;
Current = Memory;
if (const BuiltinType *BT = Ty->getAs<BuiltinType>()) {
BuiltinType::Kind k = BT->getKind();
if (k == BuiltinType::Void) {
Current = NoClass;
} else if (k == BuiltinType::Int128 || k == BuiltinType::UInt128) {
Lo = Integer;
Hi = Integer;
} else if (k >= BuiltinType::Bool && k <= BuiltinType::LongLong) {
Current = Integer;
} else if ((k == BuiltinType::Float || k == BuiltinType::Double) ||
(k == BuiltinType::LongDouble &&
getTarget().getTriple().getOS() == llvm::Triple::NaCl)) {
Current = SSE;
} else if (k == BuiltinType::LongDouble) {
Lo = X87;
Hi = X87Up;
}
// FIXME: _Decimal32 and _Decimal64 are SSE.
// FIXME: _float128 and _Decimal128 are (SSE, SSEUp).
return;
}
if (const EnumType *ET = Ty->getAs<EnumType>()) {
// Classify the underlying integer type.
classify(ET->getDecl()->getIntegerType(), OffsetBase, Lo, Hi, isNamedArg);
return;
}
if (Ty->hasPointerRepresentation()) {
Current = Integer;
return;
}
if (Ty->isMemberPointerType()) {
if (Ty->isMemberFunctionPointerType() && Has64BitPointers)
Lo = Hi = Integer;
else
Current = Integer;
return;
}
if (const VectorType *VT = Ty->getAs<VectorType>()) {
uint64_t Size = getContext().getTypeSize(VT);
if (Size == 32) {
// gcc passes all <4 x char>, <2 x short>, <1 x int>, <1 x
// float> as integer.
Current = Integer;
// If this type crosses an eightbyte boundary, it should be
// split.
uint64_t EB_Real = (OffsetBase) / 64;
uint64_t EB_Imag = (OffsetBase + Size - 1) / 64;
if (EB_Real != EB_Imag)
Hi = Lo;
} else if (Size == 64) {
// gcc passes <1 x double> in memory. :(
if (VT->getElementType()->isSpecificBuiltinType(BuiltinType::Double))
return;
// gcc passes <1 x long long> as INTEGER.
if (VT->getElementType()->isSpecificBuiltinType(BuiltinType::LongLong) ||
VT->getElementType()->isSpecificBuiltinType(BuiltinType::ULongLong) ||
VT->getElementType()->isSpecificBuiltinType(BuiltinType::Long) ||
VT->getElementType()->isSpecificBuiltinType(BuiltinType::ULong))
Current = Integer;
else
Current = SSE;
// If this type crosses an eightbyte boundary, it should be
// split.
if (OffsetBase && OffsetBase != 64)
Hi = Lo;
} else if (Size == 128 || (HasAVX && isNamedArg && Size == 256)) {
// Arguments of 256-bits are split into four eightbyte chunks. The
// least significant one belongs to class SSE and all the others to class
// SSEUP. The original Lo and Hi design considers that types can't be
// greater than 128-bits, so a 64-bit split in Hi and Lo makes sense.
// This design isn't correct for 256-bits, but since there're no cases
// where the upper parts would need to be inspected, avoid adding
// complexity and just consider Hi to match the 64-256 part.
//
// Note that per 3.5.7 of AMD64-ABI, 256-bit args are only passed in
// registers if they are "named", i.e. not part of the "..." of a
// variadic function.
Lo = SSE;
Hi = SSEUp;
}
return;
}
if (const ComplexType *CT = Ty->getAs<ComplexType>()) {
QualType ET = getContext().getCanonicalType(CT->getElementType());
uint64_t Size = getContext().getTypeSize(Ty);
if (ET->isIntegralOrEnumerationType()) {
if (Size <= 64)
Current = Integer;
else if (Size <= 128)
Lo = Hi = Integer;
} else if (ET == getContext().FloatTy)
Current = SSE;
else if (ET == getContext().DoubleTy ||
(ET == getContext().LongDoubleTy &&
getTarget().getTriple().getOS() == llvm::Triple::NaCl))
Lo = Hi = SSE;
else if (ET == getContext().LongDoubleTy)
Current = ComplexX87;
// If this complex type crosses an eightbyte boundary then it
// should be split.
uint64_t EB_Real = (OffsetBase) / 64;
uint64_t EB_Imag = (OffsetBase + getContext().getTypeSize(ET)) / 64;
if (Hi == NoClass && EB_Real != EB_Imag)
Hi = Lo;
return;
}
if (const ConstantArrayType *AT = getContext().getAsConstantArrayType(Ty)) {
// Arrays are treated like structures.
uint64_t Size = getContext().getTypeSize(Ty);
// AMD64-ABI 3.2.3p2: Rule 1. If the size of an object is larger
// than four eightbytes, ..., it has class MEMORY.
if (Size > 256)
return;
// AMD64-ABI 3.2.3p2: Rule 1. If ..., or it contains unaligned
// fields, it has class MEMORY.
//
// Only need to check alignment of array base.
if (OffsetBase % getContext().getTypeAlign(AT->getElementType()))
return;
// Otherwise implement simplified merge. We could be smarter about
// this, but it isn't worth it and would be harder to verify.
Current = NoClass;
uint64_t EltSize = getContext().getTypeSize(AT->getElementType());
uint64_t ArraySize = AT->getSize().getZExtValue();
// The only case a 256-bit wide vector could be used is when the array
// contains a single 256-bit element. Since Lo and Hi logic isn't extended
// to work for sizes wider than 128, early check and fallback to memory.
if (Size > 128 && EltSize != 256)
return;
for (uint64_t i=0, Offset=OffsetBase; i<ArraySize; ++i, Offset += EltSize) {
Class FieldLo, FieldHi;
classify(AT->getElementType(), Offset, FieldLo, FieldHi, isNamedArg);
Lo = merge(Lo, FieldLo);
Hi = merge(Hi, FieldHi);
if (Lo == Memory || Hi == Memory)
break;
}
postMerge(Size, Lo, Hi);
assert((Hi != SSEUp || Lo == SSE) && "Invalid SSEUp array classification.");
return;
}
if (const RecordType *RT = Ty->getAs<RecordType>()) {
uint64_t Size = getContext().getTypeSize(Ty);
// AMD64-ABI 3.2.3p2: Rule 1. If the size of an object is larger
// than four eightbytes, ..., it has class MEMORY.
if (Size > 256)
return;
// AMD64-ABI 3.2.3p2: Rule 2. If a C++ object has either a non-trivial
// copy constructor or a non-trivial destructor, it is passed by invisible
// reference.
if (getRecordArgABI(RT, CGT))
return;
const RecordDecl *RD = RT->getDecl();
// Assume variable sized types are passed in memory.
if (RD->hasFlexibleArrayMember())
return;
const ASTRecordLayout &Layout = getContext().getASTRecordLayout(RD);
// Reset Lo class, this will be recomputed.
Current = NoClass;
// If this is a C++ record, classify the bases first.
if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD)) {
for (CXXRecordDecl::base_class_const_iterator i = CXXRD->bases_begin(),
e = CXXRD->bases_end(); i != e; ++i) {
assert(!i->isVirtual() && !i->getType()->isDependentType() &&
"Unexpected base class!");
const CXXRecordDecl *Base =
cast<CXXRecordDecl>(i->getType()->getAs<RecordType>()->getDecl());
// Classify this field.
//
// AMD64-ABI 3.2.3p2: Rule 3. If the size of the aggregate exceeds a
// single eightbyte, each is classified separately. Each eightbyte gets
// initialized to class NO_CLASS.
Class FieldLo, FieldHi;
uint64_t Offset =
OffsetBase + getContext().toBits(Layout.getBaseClassOffset(Base));
classify(i->getType(), Offset, FieldLo, FieldHi, isNamedArg);
Lo = merge(Lo, FieldLo);
Hi = merge(Hi, FieldHi);
if (Lo == Memory || Hi == Memory)
break;
}
}
// Classify the fields one at a time, merging the results.
unsigned idx = 0;
for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end();
i != e; ++i, ++idx) {
uint64_t Offset = OffsetBase + Layout.getFieldOffset(idx);
bool BitField = i->isBitField();
// AMD64-ABI 3.2.3p2: Rule 1. If the size of an object is larger than
// four eightbytes, or it contains unaligned fields, it has class MEMORY.
//
// The only case a 256-bit wide vector could be used is when the struct
// contains a single 256-bit element. Since Lo and Hi logic isn't extended
// to work for sizes wider than 128, early check and fallback to memory.
//
if (Size > 128 && getContext().getTypeSize(i->getType()) != 256) {
Lo = Memory;
return;
}
// Note, skip this test for bit-fields, see below.
if (!BitField && Offset % getContext().getTypeAlign(i->getType())) {
Lo = Memory;
return;
}
// Classify this field.
//
// AMD64-ABI 3.2.3p2: Rule 3. If the size of the aggregate
// exceeds a single eightbyte, each is classified
// separately. Each eightbyte gets initialized to class
// NO_CLASS.
Class FieldLo, FieldHi;
// Bit-fields require special handling, they do not force the
// structure to be passed in memory even if unaligned, and
// therefore they can straddle an eightbyte.
if (BitField) {
// Ignore padding bit-fields.
if (i->isUnnamedBitfield())
continue;
uint64_t Offset = OffsetBase + Layout.getFieldOffset(idx);
uint64_t Size = i->getBitWidthValue(getContext());
uint64_t EB_Lo = Offset / 64;
uint64_t EB_Hi = (Offset + Size - 1) / 64;
FieldLo = FieldHi = NoClass;
if (EB_Lo) {
assert(EB_Hi == EB_Lo && "Invalid classification, type > 16 bytes.");
FieldLo = NoClass;
FieldHi = Integer;
} else {
FieldLo = Integer;
FieldHi = EB_Hi ? Integer : NoClass;
}
} else
classify(i->getType(), Offset, FieldLo, FieldHi, isNamedArg);
Lo = merge(Lo, FieldLo);
Hi = merge(Hi, FieldHi);
if (Lo == Memory || Hi == Memory)
break;
}
postMerge(Size, Lo, Hi);
}
}
ABIArgInfo X86_64ABIInfo::getIndirectReturnResult(QualType Ty) const {
// If this is a scalar LLVM value then assume LLVM will pass it in the right
// place naturally.
if (!isAggregateTypeForABI(Ty)) {
// Treat an enum type as its underlying type.
if (const EnumType *EnumTy = Ty->getAs<EnumType>())
Ty = EnumTy->getDecl()->getIntegerType();
return (Ty->isPromotableIntegerType() ?
ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
}
return ABIArgInfo::getIndirect(0);
}
bool X86_64ABIInfo::IsIllegalVectorType(QualType Ty) const {
if (const VectorType *VecTy = Ty->getAs<VectorType>()) {
uint64_t Size = getContext().getTypeSize(VecTy);
unsigned LargestVector = HasAVX ? 256 : 128;
if (Size <= 64 || Size > LargestVector)
return true;
}
return false;
}
ABIArgInfo X86_64ABIInfo::getIndirectResult(QualType Ty,
unsigned freeIntRegs) const {
// If this is a scalar LLVM value then assume LLVM will pass it in the right
// place naturally.
//
// This assumption is optimistic, as there could be free registers available
// when we need to pass this argument in memory, and LLVM could try to pass
// the argument in the free register. This does not seem to happen currently,
// but this code would be much safer if we could mark the argument with
// 'onstack'. See PR12193.
if (!isAggregateTypeForABI(Ty) && !IsIllegalVectorType(Ty)) {
// Treat an enum type as its underlying type.
if (const EnumType *EnumTy = Ty->getAs<EnumType>())
Ty = EnumTy->getDecl()->getIntegerType();
return (Ty->isPromotableIntegerType() ?
ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
}
if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, CGT))
return ABIArgInfo::getIndirect(0, RAA == CGCXXABI::RAA_DirectInMemory);
// Compute the byval alignment. We specify the alignment of the byval in all
// cases so that the mid-level optimizer knows the alignment of the byval.
unsigned Align = std::max(getContext().getTypeAlign(Ty) / 8, 8U);
// Attempt to avoid passing indirect results using byval when possible. This
// is important for good codegen.
//
// We do this by coercing the value into a scalar type which the backend can
// handle naturally (i.e., without using byval).
//
// For simplicity, we currently only do this when we have exhausted all of the
// free integer registers. Doing this when there are free integer registers
// would require more care, as we would have to ensure that the coerced value
// did not claim the unused register. That would require either reording the
// arguments to the function (so that any subsequent inreg values came first),
// or only doing this optimization when there were no following arguments that
// might be inreg.
//
// We currently expect it to be rare (particularly in well written code) for
// arguments to be passed on the stack when there are still free integer
// registers available (this would typically imply large structs being passed
// by value), so this seems like a fair tradeoff for now.
//
// We can revisit this if the backend grows support for 'onstack' parameter
// attributes. See PR12193.
if (freeIntRegs == 0) {
uint64_t Size = getContext().getTypeSize(Ty);
// If this type fits in an eightbyte, coerce it into the matching integral
// type, which will end up on the stack (with alignment 8).
if (Align == 8 && Size <= 64)
return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(),
Size));
}
return ABIArgInfo::getIndirect(Align);
}
/// GetByteVectorType - The ABI specifies that a value should be passed in an
/// full vector XMM/YMM register. Pick an LLVM IR type that will be passed as a
/// vector register.
llvm::Type *X86_64ABIInfo::GetByteVectorType(QualType Ty) const {
llvm::Type *IRType = CGT.ConvertType(Ty);
// Wrapper structs that just contain vectors are passed just like vectors,
// strip them off if present.
llvm::StructType *STy = dyn_cast<llvm::StructType>(IRType);
while (STy && STy->getNumElements() == 1) {
IRType = STy->getElementType(0);
STy = dyn_cast<llvm::StructType>(IRType);
}
// If the preferred type is a 16-byte vector, prefer to pass it.
if (llvm::VectorType *VT = dyn_cast<llvm::VectorType>(IRType)){
llvm::Type *EltTy = VT->getElementType();
unsigned BitWidth = VT->getBitWidth();
if ((BitWidth >= 128 && BitWidth <= 256) &&
(EltTy->isFloatTy() || EltTy->isDoubleTy() ||
EltTy->isIntegerTy(8) || EltTy->isIntegerTy(16) ||
EltTy->isIntegerTy(32) || EltTy->isIntegerTy(64) ||
EltTy->isIntegerTy(128)))
return VT;
}
return llvm::VectorType::get(llvm::Type::getDoubleTy(getVMContext()), 2);
}
/// BitsContainNoUserData - Return true if the specified [start,end) bit range
/// is known to either be off the end of the specified type or being in
/// alignment padding. The user type specified is known to be at most 128 bits
/// in size, and have passed through X86_64ABIInfo::classify with a successful
/// classification that put one of the two halves in the INTEGER class.
///
/// It is conservatively correct to return false.
static bool BitsContainNoUserData(QualType Ty, unsigned StartBit,
unsigned EndBit, ASTContext &Context) {
// If the bytes being queried are off the end of the type, there is no user
// data hiding here. This handles analysis of builtins, vectors and other
// types that don't contain interesting padding.
unsigned TySize = (unsigned)Context.getTypeSize(Ty);
if (TySize <= StartBit)
return true;
if (const ConstantArrayType *AT = Context.getAsConstantArrayType(Ty)) {
unsigned EltSize = (unsigned)Context.getTypeSize(AT->getElementType());
unsigned NumElts = (unsigned)AT->getSize().getZExtValue();
// Check each element to see if the element overlaps with the queried range.
for (unsigned i = 0; i != NumElts; ++i) {
// If the element is after the span we care about, then we're done..
unsigned EltOffset = i*EltSize;
if (EltOffset >= EndBit) break;
unsigned EltStart = EltOffset < StartBit ? StartBit-EltOffset :0;
if (!BitsContainNoUserData(AT->getElementType(), EltStart,
EndBit-EltOffset, Context))
return false;
}
// If it overlaps no elements, then it is safe to process as padding.
return true;
}
if (const RecordType *RT = Ty->getAs<RecordType>()) {
const RecordDecl *RD = RT->getDecl();
const ASTRecordLayout &Layout = Context.getASTRecordLayout(RD);
// If this is a C++ record, check the bases first.
if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD)) {
for (CXXRecordDecl::base_class_const_iterator i = CXXRD->bases_begin(),
e = CXXRD->bases_end(); i != e; ++i) {
assert(!i->isVirtual() && !i->getType()->isDependentType() &&
"Unexpected base class!");
const CXXRecordDecl *Base =
cast<CXXRecordDecl>(i->getType()->getAs<RecordType>()->getDecl());
// If the base is after the span we care about, ignore it.
unsigned BaseOffset = Context.toBits(Layout.getBaseClassOffset(Base));
if (BaseOffset >= EndBit) continue;
unsigned BaseStart = BaseOffset < StartBit ? StartBit-BaseOffset :0;
if (!BitsContainNoUserData(i->getType(), BaseStart,
EndBit-BaseOffset, Context))
return false;
}
}
// Verify that no field has data that overlaps the region of interest. Yes
// this could be sped up a lot by being smarter about queried fields,
// however we're only looking at structs up to 16 bytes, so we don't care
// much.
unsigned idx = 0;
for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end();
i != e; ++i, ++idx) {
unsigned FieldOffset = (unsigned)Layout.getFieldOffset(idx);
// If we found a field after the region we care about, then we're done.
if (FieldOffset >= EndBit) break;
unsigned FieldStart = FieldOffset < StartBit ? StartBit-FieldOffset :0;
if (!BitsContainNoUserData(i->getType(), FieldStart, EndBit-FieldOffset,
Context))
return false;
}
// If nothing in this record overlapped the area of interest, then we're
// clean.
return true;
}
return false;
}
/// ContainsFloatAtOffset - Return true if the specified LLVM IR type has a
/// float member at the specified offset. For example, {int,{float}} has a
/// float at offset 4. It is conservatively correct for this routine to return
/// false.
static bool ContainsFloatAtOffset(llvm::Type *IRType, unsigned IROffset,
const llvm::DataLayout &TD) {
// Base case if we find a float.
if (IROffset == 0 && IRType->isFloatTy())
return true;
// If this is a struct, recurse into the field at the specified offset.
if (llvm::StructType *STy = dyn_cast<llvm::StructType>(IRType)) {
const llvm::StructLayout *SL = TD.getStructLayout(STy);
unsigned Elt = SL->getElementContainingOffset(IROffset);
IROffset -= SL->getElementOffset(Elt);
return ContainsFloatAtOffset(STy->getElementType(Elt), IROffset, TD);
}
// If this is an array, recurse into the field at the specified offset.
if (llvm::ArrayType *ATy = dyn_cast<llvm::ArrayType>(IRType)) {
llvm::Type *EltTy = ATy->getElementType();
unsigned EltSize = TD.getTypeAllocSize(EltTy);
IROffset -= IROffset/EltSize*EltSize;
return ContainsFloatAtOffset(EltTy, IROffset, TD);
}
return false;
}
/// GetSSETypeAtOffset - Return a type that will be passed by the backend in the
/// low 8 bytes of an XMM register, corresponding to the SSE class.
llvm::Type *X86_64ABIInfo::
GetSSETypeAtOffset(llvm::Type *IRType, unsigned IROffset,
QualType SourceTy, unsigned SourceOffset) const {
// The only three choices we have are either double, <2 x float>, or float. We
// pass as float if the last 4 bytes is just padding. This happens for
// structs that contain 3 floats.
if (BitsContainNoUserData(SourceTy, SourceOffset*8+32,
SourceOffset*8+64, getContext()))
return llvm::Type::getFloatTy(getVMContext());
// We want to pass as <2 x float> if the LLVM IR type contains a float at
// offset+0 and offset+4. Walk the LLVM IR type to find out if this is the
// case.
if (ContainsFloatAtOffset(IRType, IROffset, getDataLayout()) &&
ContainsFloatAtOffset(IRType, IROffset+4, getDataLayout()))
return llvm::VectorType::get(llvm::Type::getFloatTy(getVMContext()), 2);
return llvm::Type::getDoubleTy(getVMContext());
}
/// GetINTEGERTypeAtOffset - The ABI specifies that a value should be passed in
/// an 8-byte GPR. This means that we either have a scalar or we are talking
/// about the high or low part of an up-to-16-byte struct. This routine picks
/// the best LLVM IR type to represent this, which may be i64 or may be anything
/// else that the backend will pass in a GPR that works better (e.g. i8, %foo*,
/// etc).
///
/// PrefType is an LLVM IR type that corresponds to (part of) the IR type for
/// the source type. IROffset is an offset in bytes into the LLVM IR type that
/// the 8-byte value references. PrefType may be null.
///
/// SourceTy is the source level type for the entire argument. SourceOffset is
/// an offset into this that we're processing (which is always either 0 or 8).
///
llvm::Type *X86_64ABIInfo::
GetINTEGERTypeAtOffset(llvm::Type *IRType, unsigned IROffset,
QualType SourceTy, unsigned SourceOffset) const {
// If we're dealing with an un-offset LLVM IR type, then it means that we're
// returning an 8-byte unit starting with it. See if we can safely use it.
if (IROffset == 0) {
// Pointers and int64's always fill the 8-byte unit.
if ((isa<llvm::PointerType>(IRType) && Has64BitPointers) ||
IRType->isIntegerTy(64))
return IRType;
// If we have a 1/2/4-byte integer, we can use it only if the rest of the
// goodness in the source type is just tail padding. This is allowed to
// kick in for struct {double,int} on the int, but not on
// struct{double,int,int} because we wouldn't return the second int. We
// have to do this analysis on the source type because we can't depend on
// unions being lowered a specific way etc.
if (IRType->isIntegerTy(8) || IRType->isIntegerTy(16) ||
IRType->isIntegerTy(32) ||
(isa<llvm::PointerType>(IRType) && !Has64BitPointers)) {
unsigned BitWidth = isa<llvm::PointerType>(IRType) ? 32 :
cast<llvm::IntegerType>(IRType)->getBitWidth();
if (BitsContainNoUserData(SourceTy, SourceOffset*8+BitWidth,
SourceOffset*8+64, getContext()))
return IRType;
}
}
if (llvm::StructType *STy = dyn_cast<llvm::StructType>(IRType)) {
// If this is a struct, recurse into the field at the specified offset.
const llvm::StructLayout *SL = getDataLayout().getStructLayout(STy);
if (IROffset < SL->getSizeInBytes()) {
unsigned FieldIdx = SL->getElementContainingOffset(IROffset);
IROffset -= SL->getElementOffset(FieldIdx);
return GetINTEGERTypeAtOffset(STy->getElementType(FieldIdx), IROffset,
SourceTy, SourceOffset);
}
}
if (llvm::ArrayType *ATy = dyn_cast<llvm::ArrayType>(IRType)) {
llvm::Type *EltTy = ATy->getElementType();
unsigned EltSize = getDataLayout().getTypeAllocSize(EltTy);
unsigned EltOffset = IROffset/EltSize*EltSize;
return GetINTEGERTypeAtOffset(EltTy, IROffset-EltOffset, SourceTy,
SourceOffset);
}
// Okay, we don't have any better idea of what to pass, so we pass this in an
// integer register that isn't too big to fit the rest of the struct.
unsigned TySizeInBytes =
(unsigned)getContext().getTypeSizeInChars(SourceTy).getQuantity();
assert(TySizeInBytes != SourceOffset && "Empty field?");
// It is always safe to classify this as an integer type up to i64 that
// isn't larger than the structure.
return llvm::IntegerType::get(getVMContext(),
std::min(TySizeInBytes-SourceOffset, 8U)*8);
}
/// GetX86_64ByValArgumentPair - Given a high and low type that can ideally
/// be used as elements of a two register pair to pass or return, return a
/// first class aggregate to represent them. For example, if the low part of
/// a by-value argument should be passed as i32* and the high part as float,
/// return {i32*, float}.
static llvm::Type *
GetX86_64ByValArgumentPair(llvm::Type *Lo, llvm::Type *Hi,
const llvm::DataLayout &TD) {
// In order to correctly satisfy the ABI, we need to the high part to start
// at offset 8. If the high and low parts we inferred are both 4-byte types
// (e.g. i32 and i32) then the resultant struct type ({i32,i32}) won't have
// the second element at offset 8. Check for this:
unsigned LoSize = (unsigned)TD.getTypeAllocSize(Lo);
unsigned HiAlign = TD.getABITypeAlignment(Hi);
unsigned HiStart = llvm::DataLayout::RoundUpAlignment(LoSize, HiAlign);
assert(HiStart != 0 && HiStart <= 8 && "Invalid x86-64 argument pair!");
// To handle this, we have to increase the size of the low part so that the
// second element will start at an 8 byte offset. We can't increase the size
// of the second element because it might make us access off the end of the
// struct.
if (HiStart != 8) {
// There are only two sorts of types the ABI generation code can produce for
// the low part of a pair that aren't 8 bytes in size: float or i8/i16/i32.
// Promote these to a larger type.
if (Lo->isFloatTy())
Lo = llvm::Type::getDoubleTy(Lo->getContext());
else {
assert(Lo->isIntegerTy() && "Invalid/unknown lo type");
Lo = llvm::Type::getInt64Ty(Lo->getContext());
}
}
llvm::StructType *Result = llvm::StructType::get(Lo, Hi, NULL);
// Verify that the second element is at an 8-byte offset.
assert(TD.getStructLayout(Result)->getElementOffset(1) == 8 &&
"Invalid x86-64 argument pair!");
return Result;
}
ABIArgInfo X86_64ABIInfo::
classifyReturnType(QualType RetTy) const {
// AMD64-ABI 3.2.3p4: Rule 1. Classify the return type with the
// classification algorithm.
X86_64ABIInfo::Class Lo, Hi;
classify(RetTy, 0, Lo, Hi, /*isNamedArg*/ true);
// Check some invariants.
assert((Hi != Memory || Lo == Memory) && "Invalid memory classification.");
assert((Hi != SSEUp || Lo == SSE) && "Invalid SSEUp classification.");
llvm::Type *ResType = 0;
switch (Lo) {
case NoClass:
if (Hi == NoClass)
return ABIArgInfo::getIgnore();
// If the low part is just padding, it takes no register, leave ResType
// null.
assert((Hi == SSE || Hi == Integer || Hi == X87Up) &&
"Unknown missing lo part");
break;
case SSEUp:
case X87Up:
llvm_unreachable("Invalid classification for lo word.");
// AMD64-ABI 3.2.3p4: Rule 2. Types of class memory are returned via
// hidden argument.
case Memory:
return getIndirectReturnResult(RetTy);
// AMD64-ABI 3.2.3p4: Rule 3. If the class is INTEGER, the next
// available register of the sequence %rax, %rdx is used.
case Integer:
ResType = GetINTEGERTypeAtOffset(CGT.ConvertType(RetTy), 0, RetTy, 0);
// If we have a sign or zero extended integer, make sure to return Extend
// so that the parameter gets the right LLVM IR attributes.
if (Hi == NoClass && isa<llvm::IntegerType>(ResType)) {
// Treat an enum type as its underlying type.
if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
RetTy = EnumTy->getDecl()->getIntegerType();
if (RetTy->isIntegralOrEnumerationType() &&
RetTy->isPromotableIntegerType())
return ABIArgInfo::getExtend();
}
break;
// AMD64-ABI 3.2.3p4: Rule 4. If the class is SSE, the next
// available SSE register of the sequence %xmm0, %xmm1 is used.
case SSE:
ResType = GetSSETypeAtOffset(CGT.ConvertType(RetTy), 0, RetTy, 0);
break;
// AMD64-ABI 3.2.3p4: Rule 6. If the class is X87, the value is
// returned on the X87 stack in %st0 as 80-bit x87 number.
case X87:
ResType = llvm::Type::getX86_FP80Ty(getVMContext());
break;
// AMD64-ABI 3.2.3p4: Rule 8. If the class is COMPLEX_X87, the real
// part of the value is returned in %st0 and the imaginary part in
// %st1.
case ComplexX87:
assert(Hi == ComplexX87 && "Unexpected ComplexX87 classification.");
ResType = llvm::StructType::get(llvm::Type::getX86_FP80Ty(getVMContext()),
llvm::Type::getX86_FP80Ty(getVMContext()),
NULL);
break;
}
llvm::Type *HighPart = 0;
switch (Hi) {
// Memory was handled previously and X87 should
// never occur as a hi class.
case Memory:
case X87:
llvm_unreachable("Invalid classification for hi word.");
case ComplexX87: // Previously handled.
case NoClass:
break;
case Integer:
HighPart = GetINTEGERTypeAtOffset(CGT.ConvertType(RetTy), 8, RetTy, 8);
if (Lo == NoClass) // Return HighPart at offset 8 in memory.
return ABIArgInfo::getDirect(HighPart, 8);
break;
case SSE:
HighPart = GetSSETypeAtOffset(CGT.ConvertType(RetTy), 8, RetTy, 8);
if (Lo == NoClass) // Return HighPart at offset 8 in memory.
return ABIArgInfo::getDirect(HighPart, 8);
break;
// AMD64-ABI 3.2.3p4: Rule 5. If the class is SSEUP, the eightbyte
// is passed in the next available eightbyte chunk if the last used
// vector register.
//
// SSEUP should always be preceded by SSE, just widen.
case SSEUp:
assert(Lo == SSE && "Unexpected SSEUp classification.");
ResType = GetByteVectorType(RetTy);
break;
// AMD64-ABI 3.2.3p4: Rule 7. If the class is X87UP, the value is
// returned together with the previous X87 value in %st0.
case X87Up:
// If X87Up is preceded by X87, we don't need to do
// anything. However, in some cases with unions it may not be
// preceded by X87. In such situations we follow gcc and pass the
// extra bits in an SSE reg.
if (Lo != X87) {
HighPart = GetSSETypeAtOffset(CGT.ConvertType(RetTy), 8, RetTy, 8);
if (Lo == NoClass) // Return HighPart at offset 8 in memory.
return ABIArgInfo::getDirect(HighPart, 8);
}
break;
}
// If a high part was specified, merge it together with the low part. It is
// known to pass in the high eightbyte of the result. We do this by forming a
// first class struct aggregate with the high and low part: {low, high}
if (HighPart)
ResType = GetX86_64ByValArgumentPair(ResType, HighPart, getDataLayout());
return ABIArgInfo::getDirect(ResType);
}
ABIArgInfo X86_64ABIInfo::classifyArgumentType(
QualType Ty, unsigned freeIntRegs, unsigned &neededInt, unsigned &neededSSE,
bool isNamedArg)
const
{
X86_64ABIInfo::Class Lo, Hi;
classify(Ty, 0, Lo, Hi, isNamedArg);
// Check some invariants.
// FIXME: Enforce these by construction.
assert((Hi != Memory || Lo == Memory) && "Invalid memory classification.");
assert((Hi != SSEUp || Lo == SSE) && "Invalid SSEUp classification.");
neededInt = 0;
neededSSE = 0;
llvm::Type *ResType = 0;
switch (Lo) {
case NoClass:
if (Hi == NoClass)
return ABIArgInfo::getIgnore();
// If the low part is just padding, it takes no register, leave ResType
// null.
assert((Hi == SSE || Hi == Integer || Hi == X87Up) &&
"Unknown missing lo part");
break;
// AMD64-ABI 3.2.3p3: Rule 1. If the class is MEMORY, pass the argument
// on the stack.
case Memory:
// AMD64-ABI 3.2.3p3: Rule 5. If the class is X87, X87UP or
// COMPLEX_X87, it is passed in memory.
case X87:
case ComplexX87:
if (getRecordArgABI(Ty, CGT) == CGCXXABI::RAA_Indirect)
++neededInt;
return getIndirectResult(Ty, freeIntRegs);
case SSEUp:
case X87Up:
llvm_unreachable("Invalid classification for lo word.");
// AMD64-ABI 3.2.3p3: Rule 2. If the class is INTEGER, the next
// available register of the sequence %rdi, %rsi, %rdx, %rcx, %r8
// and %r9 is used.
case Integer:
++neededInt;
// Pick an 8-byte type based on the preferred type.
ResType = GetINTEGERTypeAtOffset(CGT.ConvertType(Ty), 0, Ty, 0);
// If we have a sign or zero extended integer, make sure to return Extend
// so that the parameter gets the right LLVM IR attributes.
if (Hi == NoClass && isa<llvm::IntegerType>(ResType)) {
// Treat an enum type as its underlying type.
if (const EnumType *EnumTy = Ty->getAs<EnumType>())
Ty = EnumTy->getDecl()->getIntegerType();
if (Ty->isIntegralOrEnumerationType() &&
Ty->isPromotableIntegerType())
return ABIArgInfo::getExtend();
}
break;
// AMD64-ABI 3.2.3p3: Rule 3. If the class is SSE, the next
// available SSE register is used, the registers are taken in the
// order from %xmm0 to %xmm7.
case SSE: {
llvm::Type *IRType = CGT.ConvertType(Ty);
ResType = GetSSETypeAtOffset(IRType, 0, Ty, 0);
++neededSSE;
break;
}
}
llvm::Type *HighPart = 0;
switch (Hi) {
// Memory was handled previously, ComplexX87 and X87 should
// never occur as hi classes, and X87Up must be preceded by X87,
// which is passed in memory.
case Memory:
case X87:
case ComplexX87:
llvm_unreachable("Invalid classification for hi word.");
case NoClass: break;
case Integer:
++neededInt;
// Pick an 8-byte type based on the preferred type.
HighPart = GetINTEGERTypeAtOffset(CGT.ConvertType(Ty), 8, Ty, 8);
if (Lo == NoClass) // Pass HighPart at offset 8 in memory.
return ABIArgInfo::getDirect(HighPart, 8);
break;
// X87Up generally doesn't occur here (long double is passed in
// memory), except in situations involving unions.
case X87Up:
case SSE:
HighPart = GetSSETypeAtOffset(CGT.ConvertType(Ty), 8, Ty, 8);
if (Lo == NoClass) // Pass HighPart at offset 8 in memory.
return ABIArgInfo::getDirect(HighPart, 8);
++neededSSE;
break;
// AMD64-ABI 3.2.3p3: Rule 4. If the class is SSEUP, the
// eightbyte is passed in the upper half of the last used SSE
// register. This only happens when 128-bit vectors are passed.
case SSEUp:
assert(Lo == SSE && "Unexpected SSEUp classification");
ResType = GetByteVectorType(Ty);
break;
}
// If a high part was specified, merge it together with the low part. It is
// known to pass in the high eightbyte of the result. We do this by forming a
// first class struct aggregate with the high and low part: {low, high}
if (HighPart)
ResType = GetX86_64ByValArgumentPair(ResType, HighPart, getDataLayout());
return ABIArgInfo::getDirect(ResType);
}
void X86_64ABIInfo::computeInfo(CGFunctionInfo &FI) const {
FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
// Keep track of the number of assigned registers.
unsigned freeIntRegs = 6, freeSSERegs = 8;
// If the return value is indirect, then the hidden argument is consuming one
// integer register.
if (FI.getReturnInfo().isIndirect())
--freeIntRegs;
bool isVariadic = FI.isVariadic();
unsigned numRequiredArgs = 0;
if (isVariadic)
numRequiredArgs = FI.getRequiredArgs().getNumRequiredArgs();
// AMD64-ABI 3.2.3p3: Once arguments are classified, the registers
// get assigned (in left-to-right order) for passing as follows...
for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end();
it != ie; ++it) {
bool isNamedArg = true;
if (isVariadic)
isNamedArg = (it - FI.arg_begin()) <
static_cast<signed>(numRequiredArgs);
unsigned neededInt, neededSSE;
it->info = classifyArgumentType(it->type, freeIntRegs, neededInt,
neededSSE, isNamedArg);
// AMD64-ABI 3.2.3p3: If there are no registers available for any
// eightbyte of an argument, the whole argument is passed on the
// stack. If registers have already been assigned for some
// eightbytes of such an argument, the assignments get reverted.
if (freeIntRegs >= neededInt && freeSSERegs >= neededSSE) {
freeIntRegs -= neededInt;
freeSSERegs -= neededSSE;
} else {
it->info = getIndirectResult(it->type, freeIntRegs);
}
}
}
static llvm::Value *EmitVAArgFromMemory(llvm::Value *VAListAddr,
QualType Ty,
CodeGenFunction &CGF) {
llvm::Value *overflow_arg_area_p =
CGF.Builder.CreateStructGEP(VAListAddr, 2, "overflow_arg_area_p");
llvm::Value *overflow_arg_area =
CGF.Builder.CreateLoad(overflow_arg_area_p, "overflow_arg_area");
// AMD64-ABI 3.5.7p5: Step 7. Align l->overflow_arg_area upwards to a 16
// byte boundary if alignment needed by type exceeds 8 byte boundary.
// It isn't stated explicitly in the standard, but in practice we use
// alignment greater than 16 where necessary.
uint64_t Align = CGF.getContext().getTypeAlign(Ty) / 8;
if (Align > 8) {
// overflow_arg_area = (overflow_arg_area + align - 1) & -align;
llvm::Value *Offset =
llvm::ConstantInt::get(CGF.Int64Ty, Align - 1);
overflow_arg_area = CGF.Builder.CreateGEP(overflow_arg_area, Offset);
llvm::Value *AsInt = CGF.Builder.CreatePtrToInt(overflow_arg_area,
CGF.Int64Ty);
llvm::Value *Mask = llvm::ConstantInt::get(CGF.Int64Ty, -(uint64_t)Align);
overflow_arg_area =
CGF.Builder.CreateIntToPtr(CGF.Builder.CreateAnd(AsInt, Mask),
overflow_arg_area->getType(),
"overflow_arg_area.align");
}
// AMD64-ABI 3.5.7p5: Step 8. Fetch type from l->overflow_arg_area.
llvm::Type *LTy = CGF.ConvertTypeForMem(Ty);
llvm::Value *Res =
CGF.Builder.CreateBitCast(overflow_arg_area,
llvm::PointerType::getUnqual(LTy));
// AMD64-ABI 3.5.7p5: Step 9. Set l->overflow_arg_area to:
// l->overflow_arg_area + sizeof(type).
// AMD64-ABI 3.5.7p5: Step 10. Align l->overflow_arg_area upwards to
// an 8 byte boundary.
uint64_t SizeInBytes = (CGF.getContext().getTypeSize(Ty) + 7) / 8;
llvm::Value *Offset =
llvm::ConstantInt::get(CGF.Int32Ty, (SizeInBytes + 7) & ~7);
overflow_arg_area = CGF.Builder.CreateGEP(overflow_arg_area, Offset,
"overflow_arg_area.next");
CGF.Builder.CreateStore(overflow_arg_area, overflow_arg_area_p);
// AMD64-ABI 3.5.7p5: Step 11. Return the fetched type.
return Res;
}
llvm::Value *X86_64ABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
CodeGenFunction &CGF) const {
// Assume that va_list type is correct; should be pointer to LLVM type:
// struct {
// i32 gp_offset;
// i32 fp_offset;
// i8* overflow_arg_area;
// i8* reg_save_area;
// };
unsigned neededInt, neededSSE;
Ty = CGF.getContext().getCanonicalType(Ty);
ABIArgInfo AI = classifyArgumentType(Ty, 0, neededInt, neededSSE,
/*isNamedArg*/false);
// AMD64-ABI 3.5.7p5: Step 1. Determine whether type may be passed
// in the registers. If not go to step 7.
if (!neededInt && !neededSSE)
return EmitVAArgFromMemory(VAListAddr, Ty, CGF);
// AMD64-ABI 3.5.7p5: Step 2. Compute num_gp to hold the number of
// general purpose registers needed to pass type and num_fp to hold
// the number of floating point registers needed.
// AMD64-ABI 3.5.7p5: Step 3. Verify whether arguments fit into
// registers. In the case: l->gp_offset > 48 - num_gp * 8 or
// l->fp_offset > 304 - num_fp * 16 go to step 7.
//
// NOTE: 304 is a typo, there are (6 * 8 + 8 * 16) = 176 bytes of
// register save space).
llvm::Value *InRegs = 0;
llvm::Value *gp_offset_p = 0, *gp_offset = 0;
llvm::Value *fp_offset_p = 0, *fp_offset = 0;
if (neededInt) {
gp_offset_p = CGF.Builder.CreateStructGEP(VAListAddr, 0, "gp_offset_p");
gp_offset = CGF.Builder.CreateLoad(gp_offset_p, "gp_offset");
InRegs = llvm::ConstantInt::get(CGF.Int32Ty, 48 - neededInt * 8);
InRegs = CGF.Builder.CreateICmpULE(gp_offset, InRegs, "fits_in_gp");
}
if (neededSSE) {
fp_offset_p = CGF.Builder.CreateStructGEP(VAListAddr, 1, "fp_offset_p");
fp_offset = CGF.Builder.CreateLoad(fp_offset_p, "fp_offset");
llvm::Value *FitsInFP =
llvm::ConstantInt::get(CGF.Int32Ty, 176 - neededSSE * 16);
FitsInFP = CGF.Builder.CreateICmpULE(fp_offset, FitsInFP, "fits_in_fp");
InRegs = InRegs ? CGF.Builder.CreateAnd(InRegs, FitsInFP) : FitsInFP;
}
llvm::BasicBlock *InRegBlock = CGF.createBasicBlock("vaarg.in_reg");
llvm::BasicBlock *InMemBlock = CGF.createBasicBlock("vaarg.in_mem");
llvm::BasicBlock *ContBlock = CGF.createBasicBlock("vaarg.end");
CGF.Builder.CreateCondBr(InRegs, InRegBlock, InMemBlock);
// Emit code to load the value if it was passed in registers.
CGF.EmitBlock(InRegBlock);
// AMD64-ABI 3.5.7p5: Step 4. Fetch type from l->reg_save_area with
// an offset of l->gp_offset and/or l->fp_offset. This may require
// copying to a temporary location in case the parameter is passed
// in different register classes or requires an alignment greater
// than 8 for general purpose registers and 16 for XMM registers.
//
// FIXME: This really results in shameful code when we end up needing to
// collect arguments from different places; often what should result in a
// simple assembling of a structure from scattered addresses has many more
// loads than necessary. Can we clean this up?
llvm::Type *LTy = CGF.ConvertTypeForMem(Ty);
llvm::Value *RegAddr =
CGF.Builder.CreateLoad(CGF.Builder.CreateStructGEP(VAListAddr, 3),
"reg_save_area");
if (neededInt && neededSSE) {
// FIXME: Cleanup.
assert(AI.isDirect() && "Unexpected ABI info for mixed regs");
llvm::StructType *ST = cast<llvm::StructType>(AI.getCoerceToType());
llvm::Value *Tmp = CGF.CreateMemTemp(Ty);
Tmp = CGF.Builder.CreateBitCast(Tmp, ST->getPointerTo());
assert(ST->getNumElements() == 2 && "Unexpected ABI info for mixed regs");
llvm::Type *TyLo = ST->getElementType(0);
llvm::Type *TyHi = ST->getElementType(1);
assert((TyLo->isFPOrFPVectorTy() ^ TyHi->isFPOrFPVectorTy()) &&
"Unexpected ABI info for mixed regs");
llvm::Type *PTyLo = llvm::PointerType::getUnqual(TyLo);
llvm::Type *PTyHi = llvm::PointerType::getUnqual(TyHi);
llvm::Value *GPAddr = CGF.Builder.CreateGEP(RegAddr, gp_offset);
llvm::Value *FPAddr = CGF.Builder.CreateGEP(RegAddr, fp_offset);
llvm::Value *RegLoAddr = TyLo->isFloatingPointTy() ? FPAddr : GPAddr;
llvm::Value *RegHiAddr = TyLo->isFloatingPointTy() ? GPAddr : FPAddr;
llvm::Value *V =
CGF.Builder.CreateLoad(CGF.Builder.CreateBitCast(RegLoAddr, PTyLo));
CGF.Builder.CreateStore(V, CGF.Builder.CreateStructGEP(Tmp, 0));
V = CGF.Builder.CreateLoad(CGF.Builder.CreateBitCast(RegHiAddr, PTyHi));
CGF.Builder.CreateStore(V, CGF.Builder.CreateStructGEP(Tmp, 1));
RegAddr = CGF.Builder.CreateBitCast(Tmp,
llvm::PointerType::getUnqual(LTy));
} else if (neededInt) {
RegAddr = CGF.Builder.CreateGEP(RegAddr, gp_offset);
RegAddr = CGF.Builder.CreateBitCast(RegAddr,
llvm::PointerType::getUnqual(LTy));
// Copy to a temporary if necessary to ensure the appropriate alignment.
std::pair<CharUnits, CharUnits> SizeAlign =
CGF.getContext().getTypeInfoInChars(Ty);
uint64_t TySize = SizeAlign.first.getQuantity();
unsigned TyAlign = SizeAlign.second.getQuantity();
if (TyAlign > 8) {
llvm::Value *Tmp = CGF.CreateMemTemp(Ty);
CGF.Builder.CreateMemCpy(Tmp, RegAddr, TySize, 8, false);
RegAddr = Tmp;
}
} else if (neededSSE == 1) {
RegAddr = CGF.Builder.CreateGEP(RegAddr, fp_offset);
RegAddr = CGF.Builder.CreateBitCast(RegAddr,
llvm::PointerType::getUnqual(LTy));
} else {
assert(neededSSE == 2 && "Invalid number of needed registers!");
// SSE registers are spaced 16 bytes apart in the register save
// area, we need to collect the two eightbytes together.
llvm::Value *RegAddrLo = CGF.Builder.CreateGEP(RegAddr, fp_offset);
llvm::Value *RegAddrHi = CGF.Builder.CreateConstGEP1_32(RegAddrLo, 16);
llvm::Type *DoubleTy = CGF.DoubleTy;
llvm::Type *DblPtrTy =
llvm::PointerType::getUnqual(DoubleTy);
llvm::StructType *ST = llvm::StructType::get(DoubleTy, DoubleTy, NULL);
llvm::Value *V, *Tmp = CGF.CreateMemTemp(Ty);
Tmp = CGF.Builder.CreateBitCast(Tmp, ST->getPointerTo());
V = CGF.Builder.CreateLoad(CGF.Builder.CreateBitCast(RegAddrLo,
DblPtrTy));
CGF.Builder.CreateStore(V, CGF.Builder.CreateStructGEP(Tmp, 0));
V = CGF.Builder.CreateLoad(CGF.Builder.CreateBitCast(RegAddrHi,
DblPtrTy));
CGF.Builder.CreateStore(V, CGF.Builder.CreateStructGEP(Tmp, 1));
RegAddr = CGF.Builder.CreateBitCast(Tmp,
llvm::PointerType::getUnqual(LTy));
}
// AMD64-ABI 3.5.7p5: Step 5. Set:
// l->gp_offset = l->gp_offset + num_gp * 8
// l->fp_offset = l->fp_offset + num_fp * 16.
if (neededInt) {
llvm::Value *Offset = llvm::ConstantInt::get(CGF.Int32Ty, neededInt * 8);
CGF.Builder.CreateStore(CGF.Builder.CreateAdd(gp_offset, Offset),
gp_offset_p);
}
if (neededSSE) {
llvm::Value *Offset = llvm::ConstantInt::get(CGF.Int32Ty, neededSSE * 16);
CGF.Builder.CreateStore(CGF.Builder.CreateAdd(fp_offset, Offset),
fp_offset_p);
}
CGF.EmitBranch(ContBlock);
// Emit code to load the value if it was passed in memory.
CGF.EmitBlock(InMemBlock);
llvm::Value *MemAddr = EmitVAArgFromMemory(VAListAddr, Ty, CGF);
// Return the appropriate result.
CGF.EmitBlock(ContBlock);
llvm::PHINode *ResAddr = CGF.Builder.CreatePHI(RegAddr->getType(), 2,
"vaarg.addr");
ResAddr->addIncoming(RegAddr, InRegBlock);
ResAddr->addIncoming(MemAddr, InMemBlock);
return ResAddr;
}
ABIArgInfo WinX86_64ABIInfo::classify(QualType Ty, bool IsReturnType) const {
if (Ty->isVoidType())
return ABIArgInfo::getIgnore();
if (const EnumType *EnumTy = Ty->getAs<EnumType>())
Ty = EnumTy->getDecl()->getIntegerType();
uint64_t Size = getContext().getTypeSize(Ty);
if (const RecordType *RT = Ty->getAs<RecordType>()) {
if (IsReturnType) {
if (isRecordReturnIndirect(RT, CGT))
return ABIArgInfo::getIndirect(0, false);
} else {
if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(RT, CGT))
return ABIArgInfo::getIndirect(0, RAA == CGCXXABI::RAA_DirectInMemory);
}
if (RT->getDecl()->hasFlexibleArrayMember())
return ABIArgInfo::getIndirect(0, /*ByVal=*/false);
// FIXME: mingw-w64-gcc emits 128-bit struct as i128
if (Size == 128 && getTarget().getTriple().getOS() == llvm::Triple::MinGW32)
return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(),
Size));
// MS x64 ABI requirement: "Any argument that doesn't fit in 8 bytes, or is
// not 1, 2, 4, or 8 bytes, must be passed by reference."
if (Size <= 64 &&
(Size & (Size - 1)) == 0)
return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(),
Size));
return ABIArgInfo::getIndirect(0, /*ByVal=*/false);
}
if (Ty->isPromotableIntegerType())
return ABIArgInfo::getExtend();
return ABIArgInfo::getDirect();
}
void WinX86_64ABIInfo::computeInfo(CGFunctionInfo &FI) const {
QualType RetTy = FI.getReturnType();
FI.getReturnInfo() = classify(RetTy, true);
for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end();
it != ie; ++it)
it->info = classify(it->type, false);
}
llvm::Value *WinX86_64ABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
CodeGenFunction &CGF) const {
llvm::Type *BPP = CGF.Int8PtrPtrTy;
CGBuilderTy &Builder = CGF.Builder;
llvm::Value *VAListAddrAsBPP = Builder.CreateBitCast(VAListAddr, BPP,
"ap");
llvm::Value *Addr = Builder.CreateLoad(VAListAddrAsBPP, "ap.cur");
llvm::Type *PTy =
llvm::PointerType::getUnqual(CGF.ConvertType(Ty));
llvm::Value *AddrTyped = Builder.CreateBitCast(Addr, PTy);
uint64_t Offset =
llvm::RoundUpToAlignment(CGF.getContext().getTypeSize(Ty) / 8, 8);
llvm::Value *NextAddr =
Builder.CreateGEP(Addr, llvm::ConstantInt::get(CGF.Int32Ty, Offset),
"ap.next");
Builder.CreateStore(NextAddr, VAListAddrAsBPP);
return AddrTyped;
}
namespace {
class NaClX86_64ABIInfo : public ABIInfo {
public:
NaClX86_64ABIInfo(CodeGen::CodeGenTypes &CGT, bool HasAVX)
: ABIInfo(CGT), PInfo(CGT), NInfo(CGT, HasAVX) {}
virtual void computeInfo(CGFunctionInfo &FI) const;
virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
CodeGenFunction &CGF) const;
private:
PNaClABIInfo PInfo; // Used for generating calls with pnaclcall callingconv.
X86_64ABIInfo NInfo; // Used for everything else.
};
class NaClX86_64TargetCodeGenInfo : public TargetCodeGenInfo {
public:
NaClX86_64TargetCodeGenInfo(CodeGen::CodeGenTypes &CGT, bool HasAVX)
: TargetCodeGenInfo(new NaClX86_64ABIInfo(CGT, HasAVX)) {}
};
}
void NaClX86_64ABIInfo::computeInfo(CGFunctionInfo &FI) const {
if (FI.getASTCallingConvention() == CC_PnaclCall)
PInfo.computeInfo(FI);
else
NInfo.computeInfo(FI);
}
llvm::Value *NaClX86_64ABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
CodeGenFunction &CGF) const {
// Always use the native convention; calling pnacl-style varargs functions
// is unuspported.
return NInfo.EmitVAArg(VAListAddr, Ty, CGF);
}
// PowerPC-32
namespace {
class PPC32TargetCodeGenInfo : public DefaultTargetCodeGenInfo {
public:
PPC32TargetCodeGenInfo(CodeGenTypes &CGT) : DefaultTargetCodeGenInfo(CGT) {}
int getDwarfEHStackPointer(CodeGen::CodeGenModule &M) const {
// This is recovered from gcc output.
return 1; // r1 is the dedicated stack pointer
}
bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
llvm::Value *Address) const;
};
}
bool
PPC32TargetCodeGenInfo::initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
llvm::Value *Address) const {
// This is calculated from the LLVM and GCC tables and verified
// against gcc output. AFAIK all ABIs use the same encoding.
CodeGen::CGBuilderTy &Builder = CGF.Builder;
llvm::IntegerType *i8 = CGF.Int8Ty;
llvm::Value *Four8 = llvm::ConstantInt::get(i8, 4);
llvm::Value *Eight8 = llvm::ConstantInt::get(i8, 8);
llvm::Value *Sixteen8 = llvm::ConstantInt::get(i8, 16);
// 0-31: r0-31, the 4-byte general-purpose registers
AssignToArrayRange(Builder, Address, Four8, 0, 31);
// 32-63: fp0-31, the 8-byte floating-point registers
AssignToArrayRange(Builder, Address, Eight8, 32, 63);
// 64-76 are various 4-byte special-purpose registers:
// 64: mq
// 65: lr
// 66: ctr
// 67: ap
// 68-75 cr0-7
// 76: xer
AssignToArrayRange(Builder, Address, Four8, 64, 76);
// 77-108: v0-31, the 16-byte vector registers
AssignToArrayRange(Builder, Address, Sixteen8, 77, 108);
// 109: vrsave
// 110: vscr
// 111: spe_acc
// 112: spefscr
// 113: sfp
AssignToArrayRange(Builder, Address, Four8, 109, 113);
return false;
}
// PowerPC-64
namespace {
/// PPC64_SVR4_ABIInfo - The 64-bit PowerPC ELF (SVR4) ABI information.
class PPC64_SVR4_ABIInfo : public DefaultABIInfo {
public:
PPC64_SVR4_ABIInfo(CodeGen::CodeGenTypes &CGT) : DefaultABIInfo(CGT) {}
bool isPromotableTypeForABI(QualType Ty) const;
ABIArgInfo classifyReturnType(QualType RetTy) const;
ABIArgInfo classifyArgumentType(QualType Ty) const;
// TODO: We can add more logic to computeInfo to improve performance.
// Example: For aggregate arguments that fit in a register, we could
// use getDirectInReg (as is done below for structs containing a single
// floating-point value) to avoid pushing them to memory on function
// entry. This would require changing the logic in PPCISelLowering
// when lowering the parameters in the caller and args in the callee.
virtual void computeInfo(CGFunctionInfo &FI) const {
FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end();
it != ie; ++it) {
// We rely on the default argument classification for the most part.
// One exception: An aggregate containing a single floating-point
// or vector item must be passed in a register if one is available.
const Type *T = isSingleElementStruct(it->type, getContext());
if (T) {
const BuiltinType *BT = T->getAs<BuiltinType>();
if (T->isVectorType() || (BT && BT->isFloatingPoint())) {
QualType QT(T, 0);
it->info = ABIArgInfo::getDirectInReg(CGT.ConvertType(QT));
continue;
}
}
it->info = classifyArgumentType(it->type);
}
}
virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr,
QualType Ty,
CodeGenFunction &CGF) const;
};
class PPC64_SVR4_TargetCodeGenInfo : public TargetCodeGenInfo {
public:
PPC64_SVR4_TargetCodeGenInfo(CodeGenTypes &CGT)
: TargetCodeGenInfo(new PPC64_SVR4_ABIInfo(CGT)) {}
int getDwarfEHStackPointer(CodeGen::CodeGenModule &M) const {
// This is recovered from gcc output.
return 1; // r1 is the dedicated stack pointer
}
bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
llvm::Value *Address) const;
};
class PPC64TargetCodeGenInfo : public DefaultTargetCodeGenInfo {
public:
PPC64TargetCodeGenInfo(CodeGenTypes &CGT) : DefaultTargetCodeGenInfo(CGT) {}
int getDwarfEHStackPointer(CodeGen::CodeGenModule &M) const {
// This is recovered from gcc output.
return 1; // r1 is the dedicated stack pointer
}
bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
llvm::Value *Address) const;
};
}
// Return true if the ABI requires Ty to be passed sign- or zero-
// extended to 64 bits.
bool
PPC64_SVR4_ABIInfo::isPromotableTypeForABI(QualType Ty) const {
// Treat an enum type as its underlying type.
if (const EnumType *EnumTy = Ty->getAs<EnumType>())
Ty = EnumTy->getDecl()->getIntegerType();
// Promotable integer types are required to be promoted by the ABI.
if (Ty->isPromotableIntegerType())
return true;
// In addition to the usual promotable integer types, we also need to
// extend all 32-bit types, since the ABI requires promotion to 64 bits.
if (const BuiltinType *BT = Ty->getAs<BuiltinType>())
switch (BT->getKind()) {
case BuiltinType::Int:
case BuiltinType::UInt:
return true;
default:
break;
}
return false;
}
ABIArgInfo
PPC64_SVR4_ABIInfo::classifyArgumentType(QualType Ty) const {
if (Ty->isAnyComplexType())
return ABIArgInfo::getDirect();
if (isAggregateTypeForABI(Ty)) {
if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, CGT))
return ABIArgInfo::getIndirect(0, RAA == CGCXXABI::RAA_DirectInMemory);
return ABIArgInfo::getIndirect(0);
}
return (isPromotableTypeForABI(Ty) ?
ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
}
ABIArgInfo
PPC64_SVR4_ABIInfo::classifyReturnType(QualType RetTy) const {
if (RetTy->isVoidType())
return ABIArgInfo::getIgnore();
if (RetTy->isAnyComplexType())
return ABIArgInfo::getDirect();
if (isAggregateTypeForABI(RetTy))
return ABIArgInfo::getIndirect(0);
return (isPromotableTypeForABI(RetTy) ?
ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
}
// Based on ARMABIInfo::EmitVAArg, adjusted for 64-bit machine.
llvm::Value *PPC64_SVR4_ABIInfo::EmitVAArg(llvm::Value *VAListAddr,
QualType Ty,
CodeGenFunction &CGF) const {
llvm::Type *BP = CGF.Int8PtrTy;
llvm::Type *BPP = CGF.Int8PtrPtrTy;
CGBuilderTy &Builder = CGF.Builder;
llvm::Value *VAListAddrAsBPP = Builder.CreateBitCast(VAListAddr, BPP, "ap");
llvm::Value *Addr = Builder.CreateLoad(VAListAddrAsBPP, "ap.cur");
// Update the va_list pointer. The pointer should be bumped by the
// size of the object. We can trust getTypeSize() except for a complex
// type whose base type is smaller than a doubleword. For these, the
// size of the object is 16 bytes; see below for further explanation.
unsigned SizeInBytes = CGF.getContext().getTypeSize(Ty) / 8;
QualType BaseTy;
unsigned CplxBaseSize = 0;
if (const ComplexType *CTy = Ty->getAs<ComplexType>()) {
BaseTy = CTy->getElementType();
CplxBaseSize = CGF.getContext().getTypeSize(BaseTy) / 8;
if (CplxBaseSize < 8)
SizeInBytes = 16;
}
unsigned Offset = llvm::RoundUpToAlignment(SizeInBytes, 8);
llvm::Value *NextAddr =
Builder.CreateGEP(Addr, llvm::ConstantInt::get(CGF.Int64Ty, Offset),
"ap.next");
Builder.CreateStore(NextAddr, VAListAddrAsBPP);
// If we have a complex type and the base type is smaller than 8 bytes,
// the ABI calls for the real and imaginary parts to be right-adjusted
// in separate doublewords. However, Clang expects us to produce a
// pointer to a structure with the two parts packed tightly. So generate
// loads of the real and imaginary parts relative to the va_list pointer,
// and store them to a temporary structure.
if (CplxBaseSize && CplxBaseSize < 8) {
llvm::Value *RealAddr = Builder.CreatePtrToInt(Addr, CGF.Int64Ty);
llvm::Value *ImagAddr = RealAddr;
RealAddr = Builder.CreateAdd(RealAddr, Builder.getInt64(8 - CplxBaseSize));
ImagAddr = Builder.CreateAdd(ImagAddr, Builder.getInt64(16 - CplxBaseSize));
llvm::Type *PBaseTy = llvm::PointerType::getUnqual(CGF.ConvertType(BaseTy));
RealAddr = Builder.CreateIntToPtr(RealAddr, PBaseTy);
ImagAddr = Builder.CreateIntToPtr(ImagAddr, PBaseTy);
llvm::Value *Real = Builder.CreateLoad(RealAddr, false, ".vareal");
llvm::Value *Imag = Builder.CreateLoad(ImagAddr, false, ".vaimag");
llvm::Value *Ptr = CGF.CreateTempAlloca(CGT.ConvertTypeForMem(Ty),
"vacplx");
llvm::Value *RealPtr = Builder.CreateStructGEP(Ptr, 0, ".real");
llvm::Value *ImagPtr = Builder.CreateStructGEP(Ptr, 1, ".imag");
Builder.CreateStore(Real, RealPtr, false);
Builder.CreateStore(Imag, ImagPtr, false);
return Ptr;
}
// If the argument is smaller than 8 bytes, it is right-adjusted in
// its doubleword slot. Adjust the pointer to pick it up from the
// correct offset.
if (SizeInBytes < 8) {
llvm::Value *AddrAsInt = Builder.CreatePtrToInt(Addr, CGF.Int64Ty);
AddrAsInt = Builder.CreateAdd(AddrAsInt, Builder.getInt64(8 - SizeInBytes));
Addr = Builder.CreateIntToPtr(AddrAsInt, BP);
}
llvm::Type *PTy = llvm::PointerType::getUnqual(CGF.ConvertType(Ty));
return Builder.CreateBitCast(Addr, PTy);
}
static bool
PPC64_initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
llvm::Value *Address) {
// This is calculated from the LLVM and GCC tables and verified
// against gcc output. AFAIK all ABIs use the same encoding.
CodeGen::CGBuilderTy &Builder = CGF.Builder;
llvm::IntegerType *i8 = CGF.Int8Ty;
llvm::Value *Four8 = llvm::ConstantInt::get(i8, 4);
llvm::Value *Eight8 = llvm::ConstantInt::get(i8, 8);
llvm::Value *Sixteen8 = llvm::ConstantInt::get(i8, 16);
// 0-31: r0-31, the 8-byte general-purpose registers
AssignToArrayRange(Builder, Address, Eight8, 0, 31);
// 32-63: fp0-31, the 8-byte floating-point registers
AssignToArrayRange(Builder, Address, Eight8, 32, 63);
// 64-76 are various 4-byte special-purpose registers:
// 64: mq
// 65: lr
// 66: ctr
// 67: ap
// 68-75 cr0-7
// 76: xer
AssignToArrayRange(Builder, Address, Four8, 64, 76);
// 77-108: v0-31, the 16-byte vector registers
AssignToArrayRange(Builder, Address, Sixteen8, 77, 108);
// 109: vrsave
// 110: vscr
// 111: spe_acc
// 112: spefscr
// 113: sfp
AssignToArrayRange(Builder, Address, Four8, 109, 113);
return false;
}
bool
PPC64_SVR4_TargetCodeGenInfo::initDwarfEHRegSizeTable(
CodeGen::CodeGenFunction &CGF,
llvm::Value *Address) const {
return PPC64_initDwarfEHRegSizeTable(CGF, Address);
}
bool
PPC64TargetCodeGenInfo::initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
llvm::Value *Address) const {
return PPC64_initDwarfEHRegSizeTable(CGF, Address);
}
//===----------------------------------------------------------------------===//
// ARM ABI Implementation
//===----------------------------------------------------------------------===//
namespace {
class ARMABIInfo : public ABIInfo {
public:
enum ABIKind {
APCS = 0,
AAPCS = 1,
AAPCS_VFP
};
private:
ABIKind Kind;
public:
ARMABIInfo(CodeGenTypes &CGT, ABIKind _Kind) : ABIInfo(CGT), Kind(_Kind) {
setRuntimeCC();
}
bool isEABI() const {
StringRef Env = getTarget().getTriple().getEnvironmentName();
return (Env == "gnueabi" || Env == "eabi" ||
Env == "android" || Env == "androideabi");
}
private:
ABIKind getABIKind() const { return Kind; }
ABIArgInfo classifyReturnType(QualType RetTy) const;
ABIArgInfo classifyArgumentType(QualType RetTy, int *VFPRegs,
unsigned &AllocatedVFP,
bool &IsHA) const;
bool isIllegalVectorType(QualType Ty) const;
virtual void computeInfo(CGFunctionInfo &FI) const;
virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
CodeGenFunction &CGF) const;
llvm::CallingConv::ID getLLVMDefaultCC() const;
llvm::CallingConv::ID getABIDefaultCC() const;
void setRuntimeCC();
};
class ARMTargetCodeGenInfo : public TargetCodeGenInfo {
public:
ARMTargetCodeGenInfo(CodeGenTypes &CGT, ARMABIInfo::ABIKind K)
:TargetCodeGenInfo(new ARMABIInfo(CGT, K)) {}
const ARMABIInfo &getABIInfo() const {
return static_cast<const ARMABIInfo&>(TargetCodeGenInfo::getABIInfo());
}
int getDwarfEHStackPointer(CodeGen::CodeGenModule &M) const {
return 13;
}
StringRef getARCRetainAutoreleasedReturnValueMarker() const {
return "mov\tr7, r7\t\t@ marker for objc_retainAutoreleaseReturnValue";
}
bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
llvm::Value *Address) const {
llvm::Value *Four8 = llvm::ConstantInt::get(CGF.Int8Ty, 4);
// 0-15 are the 16 integer registers.
AssignToArrayRange(CGF.Builder, Address, Four8, 0, 15);
return false;
}
unsigned getSizeOfUnwindException() const {
if (getABIInfo().isEABI()) return 88;
return TargetCodeGenInfo::getSizeOfUnwindException();
}
};
}
void ARMABIInfo::computeInfo(CGFunctionInfo &FI) const {
// To correctly handle Homogeneous Aggregate, we need to keep track of the
// VFP registers allocated so far.
// C.1.vfp If the argument is a VFP CPRC and there are sufficient consecutive
// VFP registers of the appropriate type unallocated then the argument is
// allocated to the lowest-numbered sequence of such registers.
// C.2.vfp If the argument is a VFP CPRC then any VFP registers that are
// unallocated are marked as unavailable.
unsigned AllocatedVFP = 0;
int VFPRegs[16] = { 0 };
FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end();
it != ie; ++it) {
unsigned PreAllocation = AllocatedVFP;
bool IsHA = false;
// 6.1.2.3 There is one VFP co-processor register class using registers
// s0-s15 (d0-d7) for passing arguments.
const unsigned NumVFPs = 16;
it->info = classifyArgumentType(it->type, VFPRegs, AllocatedVFP, IsHA);
// If we do not have enough VFP registers for the HA, any VFP registers
// that are unallocated are marked as unavailable. To achieve this, we add
// padding of (NumVFPs - PreAllocation) floats.
if (IsHA && AllocatedVFP > NumVFPs && PreAllocation < NumVFPs) {
llvm::Type *PaddingTy = llvm::ArrayType::get(
llvm::Type::getFloatTy(getVMContext()), NumVFPs - PreAllocation);
it->info = ABIArgInfo::getExpandWithPadding(false, PaddingTy);
}
}
// Always honor user-specified calling convention.
if (FI.getCallingConvention() != llvm::CallingConv::C)
return;
llvm::CallingConv::ID cc = getRuntimeCC();
if (cc != llvm::CallingConv::C)
FI.setEffectiveCallingConvention(cc);
}
/// Return the default calling convention that LLVM will use.
llvm::CallingConv::ID ARMABIInfo::getLLVMDefaultCC() const {
// The default calling convention that LLVM will infer.
if (getTarget().getTriple().getEnvironmentName()=="gnueabihf")
return llvm::CallingConv::ARM_AAPCS_VFP;
else if (isEABI())
return llvm::CallingConv::ARM_AAPCS;
else
return llvm::CallingConv::ARM_APCS;
}
/// Return the calling convention that our ABI would like us to use
/// as the C calling convention.
llvm::CallingConv::ID ARMABIInfo::getABIDefaultCC() const {
switch (getABIKind()) {
case APCS: return llvm::CallingConv::ARM_APCS;
case AAPCS: return llvm::CallingConv::ARM_AAPCS;
case AAPCS_VFP: return llvm::CallingConv::ARM_AAPCS_VFP;
}
llvm_unreachable("bad ABI kind");
}
void ARMABIInfo::setRuntimeCC() {
assert(getRuntimeCC() == llvm::CallingConv::C);
// Don't muddy up the IR with a ton of explicit annotations if
// they'd just match what LLVM will infer from the triple.
llvm::CallingConv::ID abiCC = getABIDefaultCC();
if (abiCC != getLLVMDefaultCC())
RuntimeCC = abiCC;
}
/// isHomogeneousAggregate - Return true if a type is an AAPCS-VFP homogeneous
/// aggregate. If HAMembers is non-null, the number of base elements
/// contained in the type is returned through it; this is used for the
/// recursive calls that check aggregate component types.
static bool isHomogeneousAggregate(QualType Ty, const Type *&Base,
ASTContext &Context,
uint64_t *HAMembers = 0) {
uint64_t Members = 0;
if (const ConstantArrayType *AT = Context.getAsConstantArrayType(Ty)) {
if (!isHomogeneousAggregate(AT->getElementType(), Base, Context, &Members))
return false;
Members *= AT->getSize().getZExtValue();
} else if (const RecordType *RT = Ty->getAs<RecordType>()) {
const RecordDecl *RD = RT->getDecl();
if (RD->hasFlexibleArrayMember())
return false;
Members = 0;
for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end();
i != e; ++i) {
const FieldDecl *FD = *i;
uint64_t FldMembers;
if (!isHomogeneousAggregate(FD->getType(), Base, Context, &FldMembers))
return false;
Members = (RD->isUnion() ?
std::max(Members, FldMembers) : Members + FldMembers);
}
} else {
Members = 1;
if (const ComplexType *CT = Ty->getAs<ComplexType>()) {
Members = 2;
Ty = CT->getElementType();
}
// Homogeneous aggregates for AAPCS-VFP must have base types of float,
// double, or 64-bit or 128-bit vectors.
if (const BuiltinType *BT = Ty->getAs<BuiltinType>()) {
if (BT->getKind() != BuiltinType::Float &&
BT->getKind() != BuiltinType::Double &&
BT->getKind() != BuiltinType::LongDouble)
return false;
} else if (const VectorType *VT = Ty->getAs<VectorType>()) {
unsigned VecSize = Context.getTypeSize(VT);
if (VecSize != 64 && VecSize != 128)
return false;
} else {
return false;
}
// The base type must be the same for all members. Vector types of the
// same total size are treated as being equivalent here.
const Type *TyPtr = Ty.getTypePtr();
if (!Base)
Base = TyPtr;
if (Base != TyPtr &&
(!Base->isVectorType() || !TyPtr->isVectorType() ||
Context.getTypeSize(Base) != Context.getTypeSize(TyPtr)))
return false;
}
// Homogeneous Aggregates can have at most 4 members of the base type.
if (HAMembers)
*HAMembers = Members;
return (Members > 0 && Members <= 4);
}
/// markAllocatedVFPs - update VFPRegs according to the alignment and
/// number of VFP registers (unit is S register) requested.
static void markAllocatedVFPs(int *VFPRegs, unsigned &AllocatedVFP,
unsigned Alignment,
unsigned NumRequired) {
// Early Exit.
if (AllocatedVFP >= 16)
return;
// C.1.vfp If the argument is a VFP CPRC and there are sufficient consecutive
// VFP registers of the appropriate type unallocated then the argument is
// allocated to the lowest-numbered sequence of such registers.
for (unsigned I = 0; I < 16; I += Alignment) {
bool FoundSlot = true;
for (unsigned J = I, JEnd = I + NumRequired; J < JEnd; J++)
if (J >= 16 || VFPRegs[J]) {
FoundSlot = false;
break;
}
if (FoundSlot) {
for (unsigned J = I, JEnd = I + NumRequired; J < JEnd; J++)
VFPRegs[J] = 1;
AllocatedVFP += NumRequired;
return;
}
}
// C.2.vfp If the argument is a VFP CPRC then any VFP registers that are
// unallocated are marked as unavailable.
for (unsigned I = 0; I < 16; I++)
VFPRegs[I] = 1;
AllocatedVFP = 17; // We do not have enough VFP registers.
}
ABIArgInfo ARMABIInfo::classifyArgumentType(QualType Ty, int *VFPRegs,
unsigned &AllocatedVFP,
bool &IsHA) const {
// We update number of allocated VFPs according to
// 6.1.2.1 The following argument types are VFP CPRCs:
// A single-precision floating-point type (including promoted
// half-precision types); A double-precision floating-point type;
// A 64-bit or 128-bit containerized vector type; Homogeneous Aggregate
// with a Base Type of a single- or double-precision floating-point type,
// 64-bit containerized vectors or 128-bit containerized vectors with one
// to four Elements.
// Handle illegal vector types here.
if (isIllegalVectorType(Ty)) {
uint64_t Size = getContext().getTypeSize(Ty);
if (Size <= 32) {
llvm::Type *ResType =
llvm::Type::getInt32Ty(getVMContext());
return ABIArgInfo::getDirect(ResType);
}
if (Size == 64) {
llvm::Type *ResType = llvm::VectorType::get(
llvm::Type::getInt32Ty(getVMContext()), 2);
markAllocatedVFPs(VFPRegs, AllocatedVFP, 2, 2);
return ABIArgInfo::getDirect(ResType);
}
if (Size == 128) {
llvm::Type *ResType = llvm::VectorType::get(
llvm::Type::getInt32Ty(getVMContext()), 4);
markAllocatedVFPs(VFPRegs, AllocatedVFP, 4, 4);
return ABIArgInfo::getDirect(ResType);
}
return ABIArgInfo::getIndirect(0, /*ByVal=*/false);
}
// Update VFPRegs for legal vector types.
if (const VectorType *VT = Ty->getAs<VectorType>()) {
uint64_t Size = getContext().getTypeSize(VT);
// Size of a legal vector should be power of 2 and above 64.
markAllocatedVFPs(VFPRegs, AllocatedVFP, Size >= 128 ? 4 : 2, Size / 32);
}
// Update VFPRegs for floating point types.
if (const BuiltinType *BT = Ty->getAs<BuiltinType>()) {
if (BT->getKind() == BuiltinType::Half ||
BT->getKind() == BuiltinType::Float)
markAllocatedVFPs(VFPRegs, AllocatedVFP, 1, 1);
if (BT->getKind() == BuiltinType::Double ||
BT->getKind() == BuiltinType::LongDouble)
markAllocatedVFPs(VFPRegs, AllocatedVFP, 2, 2);
}
if (!isAggregateTypeForABI(Ty)) {
// Treat an enum type as its underlying type.
if (const EnumType *EnumTy = Ty->getAs<EnumType>())
Ty = EnumTy->getDecl()->getIntegerType();
return (Ty->isPromotableIntegerType() ?
ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
}
if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, CGT))
return ABIArgInfo::getIndirect(0, RAA == CGCXXABI::RAA_DirectInMemory);
// Ignore empty records.
if (isEmptyRecord(getContext(), Ty, true))
return ABIArgInfo::getIgnore();
if (getABIKind() == ARMABIInfo::AAPCS_VFP) {
// Homogeneous Aggregates need to be expanded when we can fit the aggregate
// into VFP registers.
const Type *Base = 0;
uint64_t Members = 0;
if (isHomogeneousAggregate(Ty, Base, getContext(), &Members)) {
assert(Base && "Base class should be set for homogeneous aggregate");
// Base can be a floating-point or a vector.
if (Base->isVectorType()) {
// ElementSize is in number of floats.
unsigned ElementSize = getContext().getTypeSize(Base) == 64 ? 2 : 4;
markAllocatedVFPs(VFPRegs, AllocatedVFP, ElementSize,
Members * ElementSize);
} else if (Base->isSpecificBuiltinType(BuiltinType::Float))
markAllocatedVFPs(VFPRegs, AllocatedVFP, 1, Members);
else {
assert(Base->isSpecificBuiltinType(BuiltinType::Double) ||
Base->isSpecificBuiltinType(BuiltinType::LongDouble));
markAllocatedVFPs(VFPRegs, AllocatedVFP, 2, Members * 2);
}
IsHA = true;
return ABIArgInfo::getExpand();
}
}
// Support byval for ARM.
// The ABI alignment for APCS is 4-byte and for AAPCS at least 4-byte and at
// most 8-byte. We realign the indirect argument if type alignment is bigger
// than ABI alignment.
uint64_t ABIAlign = 4;
uint64_t TyAlign = getContext().getTypeAlign(Ty) / 8;
if (getABIKind() == ARMABIInfo::AAPCS_VFP ||
getABIKind() == ARMABIInfo::AAPCS)
ABIAlign = std::min(std::max(TyAlign, (uint64_t)4), (uint64_t)8);
if (getContext().getTypeSizeInChars(Ty) > CharUnits::fromQuantity(64)) {
return ABIArgInfo::getIndirect(0, /*ByVal=*/true,
/*Realign=*/TyAlign > ABIAlign);
}
// Otherwise, pass by coercing to a structure of the appropriate size.
llvm::Type* ElemTy;
unsigned SizeRegs;
// FIXME: Try to match the types of the arguments more accurately where
// we can.
if (getContext().getTypeAlign(Ty) <= 32) {
ElemTy = llvm::Type::getInt32Ty(getVMContext());
SizeRegs = (getContext().getTypeSize(Ty) + 31) / 32;
} else {
ElemTy = llvm::Type::getInt64Ty(getVMContext());
SizeRegs = (getContext().getTypeSize(Ty) + 63) / 64;
}
llvm::Type *STy =
llvm::StructType::get(llvm::ArrayType::get(ElemTy, SizeRegs), NULL);
return ABIArgInfo::getDirect(STy);
}
static bool isIntegerLikeType(QualType Ty, ASTContext &Context,
llvm::LLVMContext &VMContext) {
// APCS, C Language Calling Conventions, Non-Simple Return Values: A structure
// is called integer-like if its size is less than or equal to one word, and
// the offset of each of its addressable sub-fields is zero.
uint64_t Size = Context.getTypeSize(Ty);
// Check that the type fits in a word.
if (Size > 32)
return false;
// FIXME: Handle vector types!
if (Ty->isVectorType())
return false;
// Float types are never treated as "integer like".
if (Ty->isRealFloatingType())
return false;
// If this is a builtin or pointer type then it is ok.
if (Ty->getAs<BuiltinType>() || Ty->isPointerType())
return true;
// Small complex integer types are "integer like".
if (const ComplexType *CT = Ty->getAs<ComplexType>())
return isIntegerLikeType(CT->getElementType(), Context, VMContext);
// Single element and zero sized arrays should be allowed, by the definition
// above, but they are not.
// Otherwise, it must be a record type.
const RecordType *RT = Ty->getAs<RecordType>();
if (!RT) return false;
// Ignore records with flexible arrays.
const RecordDecl *RD = RT->getDecl();
if (RD->hasFlexibleArrayMember())
return false;
// Check that all sub-fields are at offset 0, and are themselves "integer
// like".
const ASTRecordLayout &Layout = Context.getASTRecordLayout(RD);
bool HadField = false;
unsigned idx = 0;
for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end();
i != e; ++i, ++idx) {
const FieldDecl *FD = *i;
// Bit-fields are not addressable, we only need to verify they are "integer
// like". We still have to disallow a subsequent non-bitfield, for example:
// struct { int : 0; int x }
// is non-integer like according to gcc.
if (FD->isBitField()) {
if (!RD->isUnion())
HadField = true;
if (!isIntegerLikeType(FD->getType(), Context, VMContext))
return false;
continue;
}
// Check if this field is at offset 0.
if (Layout.getFieldOffset(idx) != 0)
return false;
if (!isIntegerLikeType(FD->getType(), Context, VMContext))
return false;
// Only allow at most one field in a structure. This doesn't match the
// wording above, but follows gcc in situations with a field following an
// empty structure.
if (!RD->isUnion()) {
if (HadField)
return false;
HadField = true;
}
}
return true;
}
ABIArgInfo ARMABIInfo::classifyReturnType(QualType RetTy) const {
if (RetTy->isVoidType())
return ABIArgInfo::getIgnore();
// Large vector types should be returned via memory.
if (RetTy->isVectorType() && getContext().getTypeSize(RetTy) > 128)
return ABIArgInfo::getIndirect(0);
if (!isAggregateTypeForABI(RetTy)) {
// Treat an enum type as its underlying type.
if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
RetTy = EnumTy->getDecl()->getIntegerType();
return (RetTy->isPromotableIntegerType() ?
ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
}
// Structures with either a non-trivial destructor or a non-trivial
// copy constructor are always indirect.
if (isRecordReturnIndirect(RetTy, CGT))
return ABIArgInfo::getIndirect(0, /*ByVal=*/false);
// Are we following APCS?
if (getABIKind() == APCS) {
if (isEmptyRecord(getContext(), RetTy, false))
return ABIArgInfo::getIgnore();
// Complex types are all returned as packed integers.
//
// FIXME: Consider using 2 x vector types if the back end handles them
// correctly.
if (RetTy->isAnyComplexType())
return ABIArgInfo::getDirect(llvm::IntegerType::get(getVMContext(),
getContext().getTypeSize(RetTy)));
// Integer like structures are returned in r0.
if (isIntegerLikeType(RetTy, getContext(), getVMContext())) {
// Return in the smallest viable integer type.
uint64_t Size = getContext().getTypeSize(RetTy);
if (Size <= 8)
return ABIArgInfo::getDirect(llvm::Type::getInt8Ty(getVMContext()));
if (Size <= 16)
return ABIArgInfo::getDirect(llvm::Type::getInt16Ty(getVMContext()));
return ABIArgInfo::getDirect(llvm::Type::getInt32Ty(getVMContext()));
}
// Otherwise return in memory.
return ABIArgInfo::getIndirect(0);
}
// Otherwise this is an AAPCS variant.
if (isEmptyRecord(getContext(), RetTy, true))
return ABIArgInfo::getIgnore();
// Check for homogeneous aggregates with AAPCS-VFP.
if (getABIKind() == AAPCS_VFP) {
const Type *Base = 0;
if (isHomogeneousAggregate(RetTy, Base, getContext())) {
assert(Base && "Base class should be set for homogeneous aggregate");
// Homogeneous Aggregates are returned directly.
return ABIArgInfo::getDirect();
}
}
// Aggregates <= 4 bytes are returned in r0; other aggregates
// are returned indirectly.
uint64_t Size = getContext().getTypeSize(RetTy);
if (Size <= 32) {
// Return in the smallest viable integer type.
if (Size <= 8)
return ABIArgInfo::getDirect(llvm::Type::getInt8Ty(getVMContext()));
if (Size <= 16)
return ABIArgInfo::getDirect(llvm::Type::getInt16Ty(getVMContext()));
return ABIArgInfo::getDirect(llvm::Type::getInt32Ty(getVMContext()));
}
return ABIArgInfo::getIndirect(0);
}
/// isIllegalVector - check whether Ty is an illegal vector type.
bool ARMABIInfo::isIllegalVectorType(QualType Ty) const {
if (const VectorType *VT = Ty->getAs<VectorType>()) {
// Check whether VT is legal.
unsigned NumElements = VT->getNumElements();
uint64_t Size = getContext().getTypeSize(VT);
// NumElements should be power of 2.
if ((NumElements & (NumElements - 1)) != 0)
return true;
// Size should be greater than 32 bits.
return Size <= 32;
}
return false;
}
llvm::Value *ARMABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
CodeGenFunction &CGF) const {
llvm::Type *BP = CGF.Int8PtrTy;
llvm::Type *BPP = CGF.Int8PtrPtrTy;
CGBuilderTy &Builder = CGF.Builder;
llvm::Value *VAListAddrAsBPP = Builder.CreateBitCast(VAListAddr, BPP, "ap");
llvm::Value *Addr = Builder.CreateLoad(VAListAddrAsBPP, "ap.cur");
if (isEmptyRecord(getContext(), Ty, true)) {
// These are ignored for parameter passing purposes.
llvm::Type *PTy = llvm::PointerType::getUnqual(CGF.ConvertType(Ty));
return Builder.CreateBitCast(Addr, PTy);
}
uint64_t Size = CGF.getContext().getTypeSize(Ty) / 8;
uint64_t TyAlign = CGF.getContext().getTypeAlign(Ty) / 8;
bool IsIndirect = false;
// The ABI alignment for 64-bit or 128-bit vectors is 8 for AAPCS and 4 for
// APCS. For AAPCS, the ABI alignment is at least 4-byte and at most 8-byte.
if (getABIKind() == ARMABIInfo::AAPCS_VFP ||
getABIKind() == ARMABIInfo::AAPCS)
TyAlign = std::min(std::max(TyAlign, (uint64_t)4), (uint64_t)8);
else
TyAlign = 4;
// Use indirect if size of the illegal vector is bigger than 16 bytes.
if (isIllegalVectorType(Ty) && Size > 16) {
IsIndirect = true;
Size = 4;
TyAlign = 4;
}
// Handle address alignment for ABI alignment > 4 bytes.
if (TyAlign > 4) {
assert((TyAlign & (TyAlign - 1)) == 0 &&
"Alignment is not power of 2!");
llvm::Value *AddrAsInt = Builder.CreatePtrToInt(Addr, CGF.Int32Ty);
AddrAsInt = Builder.CreateAdd(AddrAsInt, Builder.getInt32(TyAlign - 1));
AddrAsInt = Builder.CreateAnd(AddrAsInt, Builder.getInt32(~(TyAlign - 1)));
Addr = Builder.CreateIntToPtr(AddrAsInt, BP, "ap.align");
}
uint64_t Offset =
llvm::RoundUpToAlignment(Size, 4);
llvm::Value *NextAddr =
Builder.CreateGEP(Addr, llvm::ConstantInt::get(CGF.Int32Ty, Offset),
"ap.next");
Builder.CreateStore(NextAddr, VAListAddrAsBPP);
if (IsIndirect)
Addr = Builder.CreateLoad(Builder.CreateBitCast(Addr, BPP));
else if (TyAlign < CGF.getContext().getTypeAlign(Ty) / 8) {
// We can't directly cast ap.cur to pointer to a vector type, since ap.cur
// may not be correctly aligned for the vector type. We create an aligned
// temporary space and copy the content over from ap.cur to the temporary
// space. This is necessary if the natural alignment of the type is greater
// than the ABI alignment.
llvm::Type *I8PtrTy = Builder.getInt8PtrTy();
CharUnits CharSize = getContext().getTypeSizeInChars(Ty);
llvm::Value *AlignedTemp = CGF.CreateTempAlloca(CGF.ConvertType(Ty),
"var.align");
llvm::Value *Dst = Builder.CreateBitCast(AlignedTemp, I8PtrTy);
llvm::Value *Src = Builder.CreateBitCast(Addr, I8PtrTy);
Builder.CreateMemCpy(Dst, Src,
llvm::ConstantInt::get(CGF.IntPtrTy, CharSize.getQuantity()),
TyAlign, false);
Addr = AlignedTemp; //The content is in aligned location.
}
llvm::Type *PTy =
llvm::PointerType::getUnqual(CGF.ConvertType(Ty));
llvm::Value *AddrTyped = Builder.CreateBitCast(Addr, PTy);
return AddrTyped;
}
namespace {
class NaClARMABIInfo : public ABIInfo {
public:
NaClARMABIInfo(CodeGen::CodeGenTypes &CGT, ARMABIInfo::ABIKind Kind)
: ABIInfo(CGT), PInfo(CGT), NInfo(CGT, Kind) {}
virtual void computeInfo(CGFunctionInfo &FI) const;
virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
CodeGenFunction &CGF) const;
private:
PNaClABIInfo PInfo; // Used for generating calls with pnaclcall callingconv.
ARMABIInfo NInfo; // Used for everything else.
};
class NaClARMTargetCodeGenInfo : public TargetCodeGenInfo {
public:
NaClARMTargetCodeGenInfo(CodeGen::CodeGenTypes &CGT, ARMABIInfo::ABIKind Kind)
: TargetCodeGenInfo(new NaClARMABIInfo(CGT, Kind)) {}
};
}
void NaClARMABIInfo::computeInfo(CGFunctionInfo &FI) const {
if (FI.getASTCallingConvention() == CC_PnaclCall)
PInfo.computeInfo(FI);
else
static_cast<const ABIInfo&>(NInfo).computeInfo(FI);
}
llvm::Value *NaClARMABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
CodeGenFunction &CGF) const {
// Always use the native convention; calling pnacl-style varargs functions
// is unsupported.
return static_cast<const ABIInfo&>(NInfo).EmitVAArg(VAListAddr, Ty, CGF);
}
//===----------------------------------------------------------------------===//
// AArch64 ABI Implementation
//===----------------------------------------------------------------------===//
namespace {
class AArch64ABIInfo : public ABIInfo {
public:
AArch64ABIInfo(CodeGenTypes &CGT) : ABIInfo(CGT) {}
private:
// The AArch64 PCS is explicit about return types and argument types being
// handled identically, so we don't need to draw a distinction between
// Argument and Return classification.
ABIArgInfo classifyGenericType(QualType Ty, int &FreeIntRegs,
int &FreeVFPRegs) const;
ABIArgInfo tryUseRegs(QualType Ty, int &FreeRegs, int RegsNeeded, bool IsInt,
llvm::Type *DirectTy = 0) const;
virtual void computeInfo(CGFunctionInfo &FI) const;
virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
CodeGenFunction &CGF) const;
};
class AArch64TargetCodeGenInfo : public TargetCodeGenInfo {
public:
AArch64TargetCodeGenInfo(CodeGenTypes &CGT)
:TargetCodeGenInfo(new AArch64ABIInfo(CGT)) {}
const AArch64ABIInfo &getABIInfo() const {
return static_cast<const AArch64ABIInfo&>(TargetCodeGenInfo::getABIInfo());
}
int getDwarfEHStackPointer(CodeGen::CodeGenModule &M) const {
return 31;
}
bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
llvm::Value *Address) const {
// 0-31 are x0-x30 and sp: 8 bytes each
llvm::Value *Eight8 = llvm::ConstantInt::get(CGF.Int8Ty, 8);
AssignToArrayRange(CGF.Builder, Address, Eight8, 0, 31);
// 64-95 are v0-v31: 16 bytes each
llvm::Value *Sixteen8 = llvm::ConstantInt::get(CGF.Int8Ty, 16);
AssignToArrayRange(CGF.Builder, Address, Sixteen8, 64, 95);
return false;
}
};
}
void AArch64ABIInfo::computeInfo(CGFunctionInfo &FI) const {
int FreeIntRegs = 8, FreeVFPRegs = 8;
FI.getReturnInfo() = classifyGenericType(FI.getReturnType(),
FreeIntRegs, FreeVFPRegs);
FreeIntRegs = FreeVFPRegs = 8;
for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end();
it != ie; ++it) {
it->info = classifyGenericType(it->type, FreeIntRegs, FreeVFPRegs);
}
}
ABIArgInfo
AArch64ABIInfo::tryUseRegs(QualType Ty, int &FreeRegs, int RegsNeeded,
bool IsInt, llvm::Type *DirectTy) const {
if (FreeRegs >= RegsNeeded) {
FreeRegs -= RegsNeeded;
return ABIArgInfo::getDirect(DirectTy);
}
llvm::Type *Padding = 0;
// We need padding so that later arguments don't get filled in anyway. That
// wouldn't happen if only ByVal arguments followed in the same category, but
// a large structure will simply seem to be a pointer as far as LLVM is
// concerned.
if (FreeRegs > 0) {
if (IsInt)
Padding = llvm::Type::getInt64Ty(getVMContext());
else
Padding = llvm::Type::getFloatTy(getVMContext());
// Either [N x i64] or [N x float].
Padding = llvm::ArrayType::get(Padding, FreeRegs);
FreeRegs = 0;
}
return ABIArgInfo::getIndirect(getContext().getTypeAlign(Ty) / 8,
/*IsByVal=*/ true, /*Realign=*/ false,
Padding);
}
ABIArgInfo AArch64ABIInfo::classifyGenericType(QualType Ty,
int &FreeIntRegs,
int &FreeVFPRegs) const {
// Can only occurs for return, but harmless otherwise.
if (Ty->isVoidType())
return ABIArgInfo::getIgnore();
// Large vector types should be returned via memory. There's no such concept
// in the ABI, but they'd be over 16 bytes anyway so no matter how they're
// classified they'd go into memory (see B.3).
if (Ty->isVectorType() && getContext().getTypeSize(Ty) > 128) {
if (FreeIntRegs > 0)
--FreeIntRegs;
return ABIArgInfo::getIndirect(0, /*ByVal=*/false);
}
// All non-aggregate LLVM types have a concrete ABI representation so they can
// be passed directly. After this block we're guaranteed to be in a
// complicated case.
if (!isAggregateTypeForABI(Ty)) {
// Treat an enum type as its underlying type.
if (const EnumType *EnumTy = Ty->getAs<EnumType>())
Ty = EnumTy->getDecl()->getIntegerType();
if (Ty->isFloatingType() || Ty->isVectorType())
return tryUseRegs(Ty, FreeVFPRegs, /*RegsNeeded=*/ 1, /*IsInt=*/ false);
assert(getContext().getTypeSize(Ty) <= 128 &&
"unexpectedly large scalar type");
int RegsNeeded = getContext().getTypeSize(Ty) > 64 ? 2 : 1;
// If the type may need padding registers to ensure "alignment", we must be
// careful when this is accounted for. Increasing the effective size covers
// all cases.
if (getContext().getTypeAlign(Ty) == 128)
RegsNeeded += FreeIntRegs % 2 != 0;
return tryUseRegs(Ty, FreeIntRegs, RegsNeeded, /*IsInt=*/ true);
}
if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, CGT)) {
if (FreeIntRegs > 0 && RAA == CGCXXABI::RAA_Indirect)
--FreeIntRegs;
return ABIArgInfo::getIndirect(0, RAA == CGCXXABI::RAA_DirectInMemory);
}
if (isEmptyRecord(getContext(), Ty, true)) {
if (!getContext().getLangOpts().CPlusPlus) {
// Empty structs outside C++ mode are a GNU extension, so no ABI can
// possibly tell us what to do. It turns out (I believe) that GCC ignores
// the object for parameter-passsing purposes.
return ABIArgInfo::getIgnore();
}
// The combination of C++98 9p5 (sizeof(struct) != 0) and the pseudocode
// description of va_arg in the PCS require that an empty struct does
// actually occupy space for parameter-passing. I'm hoping for a
// clarification giving an explicit paragraph to point to in future.
return tryUseRegs(Ty, FreeIntRegs, /*RegsNeeded=*/ 1, /*IsInt=*/ true,
llvm::Type::getInt8Ty(getVMContext()));
}
// Homogeneous vector aggregates get passed in registers or on the stack.
const Type *Base = 0;
uint64_t NumMembers = 0;
if (isHomogeneousAggregate(Ty, Base, getContext(), &NumMembers)) {
assert(Base && "Base class should be set for homogeneous aggregate");
// Homogeneous aggregates are passed and returned directly.
return tryUseRegs(Ty, FreeVFPRegs, /*RegsNeeded=*/ NumMembers,
/*IsInt=*/ false);
}
uint64_t Size = getContext().getTypeSize(Ty);
if (Size <= 128) {
// Small structs can use the same direct type whether they're in registers
// or on the stack.
llvm::Type *BaseTy;
unsigned NumBases;
int SizeInRegs = (Size + 63) / 64;
if (getContext().getTypeAlign(Ty) == 128) {
BaseTy = llvm::Type::getIntNTy(getVMContext(), 128);
NumBases = 1;
// If the type may need padding registers to ensure "alignment", we must
// be careful when this is accounted for. Increasing the effective size
// covers all cases.
SizeInRegs += FreeIntRegs % 2 != 0;
} else {
BaseTy = llvm::Type::getInt64Ty(getVMContext());
NumBases = SizeInRegs;
}
llvm::Type *DirectTy = llvm::ArrayType::get(BaseTy, NumBases);
return tryUseRegs(Ty, FreeIntRegs, /*RegsNeeded=*/ SizeInRegs,
/*IsInt=*/ true, DirectTy);
}
// If the aggregate is > 16 bytes, it's passed and returned indirectly. In
// LLVM terms the return uses an "sret" pointer, but that's handled elsewhere.
--FreeIntRegs;
return ABIArgInfo::getIndirect(0, /* byVal = */ false);
}
llvm::Value *AArch64ABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
CodeGenFunction &CGF) const {
// The AArch64 va_list type and handling is specified in the Procedure Call
// Standard, section B.4:
//
// struct {
// void *__stack;
// void *__gr_top;
// void *__vr_top;
// int __gr_offs;
// int __vr_offs;
// };
assert(!CGF.CGM.getDataLayout().isBigEndian()
&& "va_arg not implemented for big-endian AArch64");
int FreeIntRegs = 8, FreeVFPRegs = 8;
Ty = CGF.getContext().getCanonicalType(Ty);
ABIArgInfo AI = classifyGenericType(Ty, FreeIntRegs, FreeVFPRegs);
llvm::BasicBlock *MaybeRegBlock = CGF.createBasicBlock("vaarg.maybe_reg");
llvm::BasicBlock *InRegBlock = CGF.createBasicBlock("vaarg.in_reg");
llvm::BasicBlock *OnStackBlock = CGF.createBasicBlock("vaarg.on_stack");
llvm::BasicBlock *ContBlock = CGF.createBasicBlock("vaarg.end");
llvm::Value *reg_offs_p = 0, *reg_offs = 0;
int reg_top_index;
int RegSize;
if (FreeIntRegs < 8) {
assert(FreeVFPRegs == 8 && "Arguments never split between int & VFP regs");
// 3 is the field number of __gr_offs
reg_offs_p = CGF.Builder.CreateStructGEP(VAListAddr, 3, "gr_offs_p");
reg_offs = CGF.Builder.CreateLoad(reg_offs_p, "gr_offs");
reg_top_index = 1; // field number for __gr_top
RegSize = 8 * (8 - FreeIntRegs);
} else {
assert(FreeVFPRegs < 8 && "Argument must go in VFP or int regs");
// 4 is the field number of __vr_offs.
reg_offs_p = CGF.Builder.CreateStructGEP(VAListAddr, 4, "vr_offs_p");
reg_offs = CGF.Builder.CreateLoad(reg_offs_p, "vr_offs");
reg_top_index = 2; // field number for __vr_top
RegSize = 16 * (8 - FreeVFPRegs);
}
//=======================================
// Find out where argument was passed
//=======================================
// If reg_offs >= 0 we're already using the stack for this type of
// argument. We don't want to keep updating reg_offs (in case it overflows,
// though anyone passing 2GB of arguments, each at most 16 bytes, deserves
// whatever they get).
llvm::Value *UsingStack = 0;
UsingStack = CGF.Builder.CreateICmpSGE(reg_offs,
llvm::ConstantInt::get(CGF.Int32Ty, 0));
CGF.Builder.CreateCondBr(UsingStack, OnStackBlock, MaybeRegBlock);
// Otherwise, at least some kind of argument could go in these registers, the
// quesiton is whether this particular type is too big.
CGF.EmitBlock(MaybeRegBlock);
// Integer arguments may need to correct register alignment (for example a
// "struct { __int128 a; };" gets passed in x_2N, x_{2N+1}). In this case we
// align __gr_offs to calculate the potential address.
if (FreeIntRegs < 8 && AI.isDirect() && getContext().getTypeAlign(Ty) > 64) {
int Align = getContext().getTypeAlign(Ty) / 8;
reg_offs = CGF.Builder.CreateAdd(reg_offs,
llvm::ConstantInt::get(CGF.Int32Ty, Align - 1),
"align_regoffs");
reg_offs = CGF.Builder.CreateAnd(reg_offs,
llvm::ConstantInt::get(CGF.Int32Ty, -Align),
"aligned_regoffs");
}
// Update the gr_offs/vr_offs pointer for next call to va_arg on this va_list.
llvm::Value *NewOffset = 0;
NewOffset = CGF.Builder.CreateAdd(reg_offs,
llvm::ConstantInt::get(CGF.Int32Ty, RegSize),
"new_reg_offs");
CGF.Builder.CreateStore(NewOffset, reg_offs_p);
// Now we're in a position to decide whether this argument really was in
// registers or not.
llvm::Value *InRegs = 0;
InRegs = CGF.Builder.CreateICmpSLE(NewOffset,
llvm::ConstantInt::get(CGF.Int32Ty, 0),
"inreg");
CGF.Builder.CreateCondBr(InRegs, InRegBlock, OnStackBlock);
//=======================================
// Argument was in registers
//=======================================
// Now we emit the code for if the argument was originally passed in
// registers. First start the appropriate block:
CGF.EmitBlock(InRegBlock);
llvm::Value *reg_top_p = 0, *reg_top = 0;
reg_top_p = CGF.Builder.CreateStructGEP(VAListAddr, reg_top_index, "reg_top_p");
reg_top = CGF.Builder.CreateLoad(reg_top_p, "reg_top");
llvm::Value *BaseAddr = CGF.Builder.CreateGEP(reg_top, reg_offs);
llvm::Value *RegAddr = 0;
llvm::Type *MemTy = llvm::PointerType::getUnqual(CGF.ConvertTypeForMem(Ty));
if (!AI.isDirect()) {
// If it's been passed indirectly (actually a struct), whatever we find from
// stored registers or on the stack will actually be a struct **.
MemTy = llvm::PointerType::getUnqual(MemTy);
}
const Type *Base = 0;
uint64_t NumMembers;
if (isHomogeneousAggregate(Ty, Base, getContext(), &NumMembers)
&& NumMembers > 1) {
// Homogeneous aggregates passed in registers will have their elements split
// and stored 16-bytes apart regardless of size (they're notionally in qN,
// qN+1, ...). We reload and store into a temporary local variable
// contiguously.
assert(AI.isDirect() && "Homogeneous aggregates should be passed directly");
llvm::Type *BaseTy = CGF.ConvertType(QualType(Base, 0));
llvm::Type *HFATy = llvm::ArrayType::get(BaseTy, NumMembers);
llvm::Value *Tmp = CGF.CreateTempAlloca(HFATy);
for (unsigned i = 0; i < NumMembers; ++i) {
llvm::Value *BaseOffset = llvm::ConstantInt::get(CGF.Int32Ty, 16 * i);
llvm::Value *LoadAddr = CGF.Builder.CreateGEP(BaseAddr, BaseOffset);
LoadAddr = CGF.Builder.CreateBitCast(LoadAddr,
llvm::PointerType::getUnqual(BaseTy));
llvm::Value *StoreAddr = CGF.Builder.CreateStructGEP(Tmp, i);
llvm::Value *Elem = CGF.Builder.CreateLoad(LoadAddr);
CGF.Builder.CreateStore(Elem, StoreAddr);
}
RegAddr = CGF.Builder.CreateBitCast(Tmp, MemTy);
} else {
// Otherwise the object is contiguous in memory
RegAddr = CGF.Builder.CreateBitCast(BaseAddr, MemTy);
}
CGF.EmitBranch(ContBlock);
//=======================================
// Argument was on the stack
//=======================================
CGF.EmitBlock(OnStackBlock);
llvm::Value *stack_p = 0, *OnStackAddr = 0;
stack_p = CGF.Builder.CreateStructGEP(VAListAddr, 0, "stack_p");
OnStackAddr = CGF.Builder.CreateLoad(stack_p, "stack");
// Again, stack arguments may need realigmnent. In this case both integer and
// floating-point ones might be affected.
if (AI.isDirect() && getContext().getTypeAlign(Ty) > 64) {
int Align = getContext().getTypeAlign(Ty) / 8;
OnStackAddr = CGF.Builder.CreatePtrToInt(OnStackAddr, CGF.Int64Ty);
OnStackAddr = CGF.Builder.CreateAdd(OnStackAddr,
llvm::ConstantInt::get(CGF.Int64Ty, Align - 1),
"align_stack");
OnStackAddr = CGF.Builder.CreateAnd(OnStackAddr,
llvm::ConstantInt::get(CGF.Int64Ty, -Align),
"align_stack");
OnStackAddr = CGF.Builder.CreateIntToPtr(OnStackAddr, CGF.Int8PtrTy);
}
uint64_t StackSize;
if (AI.isDirect())
StackSize = getContext().getTypeSize(Ty) / 8;
else
StackSize = 8;
// All stack slots are 8 bytes
StackSize = llvm::RoundUpToAlignment(StackSize, 8);
llvm::Value *StackSizeC = llvm::ConstantInt::get(CGF.Int32Ty, StackSize);
llvm::Value *NewStack = CGF.Builder.CreateGEP(OnStackAddr, StackSizeC,
"new_stack");
// Write the new value of __stack for the next call to va_arg
CGF.Builder.CreateStore(NewStack, stack_p);
OnStackAddr = CGF.Builder.CreateBitCast(OnStackAddr, MemTy);
CGF.EmitBranch(ContBlock);
//=======================================
// Tidy up
//=======================================
CGF.EmitBlock(ContBlock);
llvm::PHINode *ResAddr = CGF.Builder.CreatePHI(MemTy, 2, "vaarg.addr");
ResAddr->addIncoming(RegAddr, InRegBlock);
ResAddr->addIncoming(OnStackAddr, OnStackBlock);
if (AI.isDirect())
return ResAddr;
return CGF.Builder.CreateLoad(ResAddr, "vaarg.addr");
}
//===----------------------------------------------------------------------===//
// NVPTX ABI Implementation
//===----------------------------------------------------------------------===//
namespace {
class NVPTXABIInfo : public ABIInfo {
public:
NVPTXABIInfo(CodeGenTypes &CGT) : ABIInfo(CGT) {}
ABIArgInfo classifyReturnType(QualType RetTy) const;
ABIArgInfo classifyArgumentType(QualType Ty) const;
virtual void computeInfo(CGFunctionInfo &FI) const;
virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
CodeGenFunction &CFG) const;
};
class NVPTXTargetCodeGenInfo : public TargetCodeGenInfo {
public:
NVPTXTargetCodeGenInfo(CodeGenTypes &CGT)
: TargetCodeGenInfo(new NVPTXABIInfo(CGT)) {}
virtual void SetTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
CodeGen::CodeGenModule &M) const;
private:
static void addKernelMetadata(llvm::Function *F);
};
ABIArgInfo NVPTXABIInfo::classifyReturnType(QualType RetTy) const {
if (RetTy->isVoidType())
return ABIArgInfo::getIgnore();
if (isAggregateTypeForABI(RetTy))
return ABIArgInfo::getIndirect(0);
return ABIArgInfo::getDirect();
}
ABIArgInfo NVPTXABIInfo::classifyArgumentType(QualType Ty) const {
if (isAggregateTypeForABI(Ty))
return ABIArgInfo::getIndirect(0);
return ABIArgInfo::getDirect();
}
void NVPTXABIInfo::computeInfo(CGFunctionInfo &FI) const {
FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end();
it != ie; ++it)
it->info = classifyArgumentType(it->type);
// Always honor user-specified calling convention.
if (FI.getCallingConvention() != llvm::CallingConv::C)
return;
FI.setEffectiveCallingConvention(getRuntimeCC());
}
llvm::Value *NVPTXABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
CodeGenFunction &CFG) const {
llvm_unreachable("NVPTX does not support varargs");
}
void NVPTXTargetCodeGenInfo::
SetTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
CodeGen::CodeGenModule &M) const{
const FunctionDecl *FD = dyn_cast<FunctionDecl>(D);
if (!FD) return;
llvm::Function *F = cast<llvm::Function>(GV);
// Perform special handling in OpenCL mode
if (M.getLangOpts().OpenCL) {
// Use OpenCL function attributes to check for kernel functions
// By default, all functions are device functions
if (FD->hasAttr<OpenCLKernelAttr>()) {
// OpenCL __kernel functions get kernel metadata
addKernelMetadata(F);
// And kernel functions are not subject to inlining
F->addFnAttr(llvm::Attribute::NoInline);
}
}
// Perform special handling in CUDA mode.
if (M.getLangOpts().CUDA) {
// CUDA __global__ functions get a kernel metadata entry. Since
// __global__ functions cannot be called from the device, we do not
// need to set the noinline attribute.
if (FD->getAttr<CUDAGlobalAttr>())
addKernelMetadata(F);
}
}
void NVPTXTargetCodeGenInfo::addKernelMetadata(llvm::Function *F) {
llvm::Module *M = F->getParent();
llvm::LLVMContext &Ctx = M->getContext();
// Get "nvvm.annotations" metadata node
llvm::NamedMDNode *MD = M->getOrInsertNamedMetadata("nvvm.annotations");
// Create !{<func-ref>, metadata !"kernel", i32 1} node
llvm::SmallVector<llvm::Value *, 3> MDVals;
MDVals.push_back(F);
MDVals.push_back(llvm::MDString::get(Ctx, "kernel"));
MDVals.push_back(llvm::ConstantInt::get(llvm::Type::getInt32Ty(Ctx), 1));
// Append metadata to nvvm.annotations
MD->addOperand(llvm::MDNode::get(Ctx, MDVals));
}
}
//===----------------------------------------------------------------------===//
// SystemZ ABI Implementation
//===----------------------------------------------------------------------===//
namespace {
class SystemZABIInfo : public ABIInfo {
public:
SystemZABIInfo(CodeGenTypes &CGT) : ABIInfo(CGT) {}
bool isPromotableIntegerType(QualType Ty) const;
bool isCompoundType(QualType Ty) const;
bool isFPArgumentType(QualType Ty) const;
ABIArgInfo classifyReturnType(QualType RetTy) const;
ABIArgInfo classifyArgumentType(QualType ArgTy) const;
virtual void computeInfo(CGFunctionInfo &FI) const {
FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end();
it != ie; ++it)
it->info = classifyArgumentType(it->type);
}
virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
CodeGenFunction &CGF) const;
};
class SystemZTargetCodeGenInfo : public TargetCodeGenInfo {
public:
SystemZTargetCodeGenInfo(CodeGenTypes &CGT)
: TargetCodeGenInfo(new SystemZABIInfo(CGT)) {}
};
}
bool SystemZABIInfo::isPromotableIntegerType(QualType Ty) const {
// Treat an enum type as its underlying type.
if (const EnumType *EnumTy = Ty->getAs<EnumType>())
Ty = EnumTy->getDecl()->getIntegerType();
// Promotable integer types are required to be promoted by the ABI.
if (Ty->isPromotableIntegerType())
return true;
// 32-bit values must also be promoted.
if (const BuiltinType *BT = Ty->getAs<BuiltinType>())
switch (BT->getKind()) {
case BuiltinType::Int:
case BuiltinType::UInt:
return true;
default:
return false;
}
return false;
}
bool SystemZABIInfo::isCompoundType(QualType Ty) const {
return Ty->isAnyComplexType() || isAggregateTypeForABI(Ty);
}
bool SystemZABIInfo::isFPArgumentType(QualType Ty) const {
if (const BuiltinType *BT = Ty->getAs<BuiltinType>())
switch (BT->getKind()) {
case BuiltinType::Float:
case BuiltinType::Double:
return true;
default:
return false;
}
if (const RecordType *RT = Ty->getAsStructureType()) {
const RecordDecl *RD = RT->getDecl();
bool Found = false;
// If this is a C++ record, check the bases first.
if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD))
for (CXXRecordDecl::base_class_const_iterator I = CXXRD->bases_begin(),
E = CXXRD->bases_end(); I != E; ++I) {
QualType Base = I->getType();
// Empty bases don't affect things either way.
if (isEmptyRecord(getContext(), Base, true))
continue;
if (Found)
return false;
Found = isFPArgumentType(Base);
if (!Found)
return false;
}
// Check the fields.
for (RecordDecl::field_iterator I = RD->field_begin(),
E = RD->field_end(); I != E; ++I) {
const FieldDecl *FD = *I;
// Empty bitfields don't affect things either way.
// Unlike isSingleElementStruct(), empty structure and array fields
// do count. So do anonymous bitfields that aren't zero-sized.
if (FD->isBitField() && FD->getBitWidthValue(getContext()) == 0)
return true;
// Unlike isSingleElementStruct(), arrays do not count.
// Nested isFPArgumentType structures still do though.
if (Found)
return false;
Found = isFPArgumentType(FD->getType());
if (!Found)
return false;
}
// Unlike isSingleElementStruct(), trailing padding is allowed.
// An 8-byte aligned struct s { float f; } is passed as a double.
return Found;
}
return false;
}
llvm::Value *SystemZABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
CodeGenFunction &CGF) const {
// Assume that va_list type is correct; should be pointer to LLVM type:
// struct {
// i64 __gpr;
// i64 __fpr;
// i8 *__overflow_arg_area;
// i8 *__reg_save_area;
// };
// Every argument occupies 8 bytes and is passed by preference in either
// GPRs or FPRs.
Ty = CGF.getContext().getCanonicalType(Ty);
ABIArgInfo AI = classifyArgumentType(Ty);
bool InFPRs = isFPArgumentType(Ty);
llvm::Type *APTy = llvm::PointerType::getUnqual(CGF.ConvertTypeForMem(Ty));
bool IsIndirect = AI.isIndirect();
unsigned UnpaddedBitSize;
if (IsIndirect) {
APTy = llvm::PointerType::getUnqual(APTy);
UnpaddedBitSize = 64;
} else
UnpaddedBitSize = getContext().getTypeSize(Ty);
unsigned PaddedBitSize = 64;
assert((UnpaddedBitSize <= PaddedBitSize) && "Invalid argument size.");
unsigned PaddedSize = PaddedBitSize / 8;
unsigned Padding = (PaddedBitSize - UnpaddedBitSize) / 8;
unsigned MaxRegs, RegCountField, RegSaveIndex, RegPadding;
if (InFPRs) {
MaxRegs = 4; // Maximum of 4 FPR arguments
RegCountField = 1; // __fpr
RegSaveIndex = 16; // save offset for f0
RegPadding = 0; // floats are passed in the high bits of an FPR
} else {
MaxRegs = 5; // Maximum of 5 GPR arguments
RegCountField = 0; // __gpr
RegSaveIndex = 2; // save offset for r2
RegPadding = Padding; // values are passed in the low bits of a GPR
}
llvm::Value *RegCountPtr =
CGF.Builder.CreateStructGEP(VAListAddr, RegCountField, "reg_count_ptr");
llvm::Value *RegCount = CGF.Builder.CreateLoad(RegCountPtr, "reg_count");
llvm::Type *IndexTy = RegCount->getType();
llvm::Value *MaxRegsV = llvm::ConstantInt::get(IndexTy, MaxRegs);
llvm::Value *InRegs = CGF.Builder.CreateICmpULT(RegCount, MaxRegsV,
"fits_in_regs");
llvm::BasicBlock *InRegBlock = CGF.createBasicBlock("vaarg.in_reg");
llvm::BasicBlock *InMemBlock = CGF.createBasicBlock("vaarg.in_mem");
llvm::BasicBlock *ContBlock = CGF.createBasicBlock("vaarg.end");
CGF.Builder.CreateCondBr(InRegs, InRegBlock, InMemBlock);
// Emit code to load the value if it was passed in registers.
CGF.EmitBlock(InRegBlock);
// Work out the address of an argument register.
llvm::Value *PaddedSizeV = llvm::ConstantInt::get(IndexTy, PaddedSize);
llvm::Value *ScaledRegCount =
CGF.Builder.CreateMul(RegCount, PaddedSizeV, "scaled_reg_count");
llvm::Value *RegBase =
llvm::ConstantInt::get(IndexTy, RegSaveIndex * PaddedSize + RegPadding);
llvm::Value *RegOffset =
CGF.Builder.CreateAdd(ScaledRegCount, RegBase, "reg_offset");
llvm::Value *RegSaveAreaPtr =
CGF.Builder.CreateStructGEP(VAListAddr, 3, "reg_save_area_ptr");
llvm::Value *RegSaveArea =
CGF.Builder.CreateLoad(RegSaveAreaPtr, "reg_save_area");
llvm::Value *RawRegAddr =
CGF.Builder.CreateGEP(RegSaveArea, RegOffset, "raw_reg_addr");
llvm::Value *RegAddr =
CGF.Builder.CreateBitCast(RawRegAddr, APTy, "reg_addr");
// Update the register count
llvm::Value *One = llvm::ConstantInt::get(IndexTy, 1);
llvm::Value *NewRegCount =
CGF.Builder.CreateAdd(RegCount, One, "reg_count");
CGF.Builder.CreateStore(NewRegCount, RegCountPtr);
CGF.EmitBranch(ContBlock);
// Emit code to load the value if it was passed in memory.
CGF.EmitBlock(InMemBlock);
// Work out the address of a stack argument.
llvm::Value *OverflowArgAreaPtr =
CGF.Builder.CreateStructGEP(VAListAddr, 2, "overflow_arg_area_ptr");
llvm::Value *OverflowArgArea =
CGF.Builder.CreateLoad(OverflowArgAreaPtr, "overflow_arg_area");
llvm::Value *PaddingV = llvm::ConstantInt::get(IndexTy, Padding);
llvm::Value *RawMemAddr =
CGF.Builder.CreateGEP(OverflowArgArea, PaddingV, "raw_mem_addr");
llvm::Value *MemAddr =
CGF.Builder.CreateBitCast(RawMemAddr, APTy, "mem_addr");
// Update overflow_arg_area_ptr pointer
llvm::Value *NewOverflowArgArea =
CGF.Builder.CreateGEP(OverflowArgArea, PaddedSizeV, "overflow_arg_area");
CGF.Builder.CreateStore(NewOverflowArgArea, OverflowArgAreaPtr);
CGF.EmitBranch(ContBlock);
// Return the appropriate result.
CGF.EmitBlock(ContBlock);
llvm::PHINode *ResAddr = CGF.Builder.CreatePHI(APTy, 2, "va_arg.addr");
ResAddr->addIncoming(RegAddr, InRegBlock);
ResAddr->addIncoming(MemAddr, InMemBlock);
if (IsIndirect)
return CGF.Builder.CreateLoad(ResAddr, "indirect_arg");
return ResAddr;
}
bool X86_32TargetCodeGenInfo::isStructReturnInRegABI(
const llvm::Triple &Triple, const CodeGenOptions &Opts) {
assert(Triple.getArch() == llvm::Triple::x86);
switch (Opts.getStructReturnConvention()) {
case CodeGenOptions::SRCK_Default:
break;
case CodeGenOptions::SRCK_OnStack: // -fpcc-struct-return
return false;
case CodeGenOptions::SRCK_InRegs: // -freg-struct-return
return true;
}
if (Triple.isOSDarwin())
return true;
switch (Triple.getOS()) {
case llvm::Triple::Cygwin:
case llvm::Triple::MinGW32:
case llvm::Triple::AuroraUX:
case llvm::Triple::DragonFly:
case llvm::Triple::FreeBSD:
case llvm::Triple::OpenBSD:
case llvm::Triple::Bitrig:
case llvm::Triple::Win32:
return true;
default:
return false;
}
}
ABIArgInfo SystemZABIInfo::classifyReturnType(QualType RetTy) const {
if (RetTy->isVoidType())
return ABIArgInfo::getIgnore();
if (isCompoundType(RetTy) || getContext().getTypeSize(RetTy) > 64)
return ABIArgInfo::getIndirect(0);
return (isPromotableIntegerType(RetTy) ?
ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
}
ABIArgInfo SystemZABIInfo::classifyArgumentType(QualType Ty) const {
// Handle the generic C++ ABI.
if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, CGT))
return ABIArgInfo::getIndirect(0, RAA == CGCXXABI::RAA_DirectInMemory);
// Integers and enums are extended to full register width.
if (isPromotableIntegerType(Ty))
return ABIArgInfo::getExtend();
// Values that are not 1, 2, 4 or 8 bytes in size are passed indirectly.
uint64_t Size = getContext().getTypeSize(Ty);
if (Size != 8 && Size != 16 && Size != 32 && Size != 64)
return ABIArgInfo::getIndirect(0);
// Handle small structures.
if (const RecordType *RT = Ty->getAs<RecordType>()) {
// Structures with flexible arrays have variable length, so really
// fail the size test above.
const RecordDecl *RD = RT->getDecl();
if (RD->hasFlexibleArrayMember())
return ABIArgInfo::getIndirect(0);
// The structure is passed as an unextended integer, a float, or a double.
llvm::Type *PassTy;
if (isFPArgumentType(Ty)) {
assert(Size == 32 || Size == 64);
if (Size == 32)
PassTy = llvm::Type::getFloatTy(getVMContext());
else
PassTy = llvm::Type::getDoubleTy(getVMContext());
} else
PassTy = llvm::IntegerType::get(getVMContext(), Size);
return ABIArgInfo::getDirect(PassTy);
}
// Non-structure compounds are passed indirectly.
if (isCompoundType(Ty))
return ABIArgInfo::getIndirect(0);
return ABIArgInfo::getDirect(0);
}
//===----------------------------------------------------------------------===//
// MSP430 ABI Implementation
//===----------------------------------------------------------------------===//
namespace {
class MSP430TargetCodeGenInfo : public TargetCodeGenInfo {
public:
MSP430TargetCodeGenInfo(CodeGenTypes &CGT)
: TargetCodeGenInfo(new DefaultABIInfo(CGT)) {}
void SetTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
CodeGen::CodeGenModule &M) const;
};
}
void MSP430TargetCodeGenInfo::SetTargetAttributes(const Decl *D,
llvm::GlobalValue *GV,
CodeGen::CodeGenModule &M) const {
if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
if (const MSP430InterruptAttr *attr = FD->getAttr<MSP430InterruptAttr>()) {
// Handle 'interrupt' attribute:
llvm::Function *F = cast<llvm::Function>(GV);
// Step 1: Set ISR calling convention.
F->setCallingConv(llvm::CallingConv::MSP430_INTR);
// Step 2: Add attributes goodness.
F->addFnAttr(llvm::Attribute::NoInline);
// Step 3: Emit ISR vector alias.
unsigned Num = attr->getNumber() / 2;
new llvm::GlobalAlias(GV->getType(), llvm::Function::ExternalLinkage,
"__isr_" + Twine(Num),
GV, &M.getModule());
}
}
}
//===----------------------------------------------------------------------===//
// MIPS ABI Implementation. This works for both little-endian and
// big-endian variants.
//===----------------------------------------------------------------------===//
namespace {
class MipsABIInfo : public ABIInfo {
bool IsO32;
unsigned MinABIStackAlignInBytes, StackAlignInBytes;
void CoerceToIntArgs(uint64_t TySize,
SmallVectorImpl<llvm::Type *> &ArgList) const;
llvm::Type* HandleAggregates(QualType Ty, uint64_t TySize) const;
llvm::Type* returnAggregateInRegs(QualType RetTy, uint64_t Size) const;
llvm::Type* getPaddingType(uint64_t Align, uint64_t Offset) const;
public:
MipsABIInfo(CodeGenTypes &CGT, bool _IsO32) :
ABIInfo(CGT), IsO32(_IsO32), MinABIStackAlignInBytes(IsO32 ? 4 : 8),
StackAlignInBytes(IsO32 ? 8 : 16) {}
ABIArgInfo classifyReturnType(QualType RetTy) const;
ABIArgInfo classifyArgumentType(QualType RetTy, uint64_t &Offset) const;
virtual void computeInfo(CGFunctionInfo &FI) const;
virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
CodeGenFunction &CGF) const;
};
class MIPSTargetCodeGenInfo : public TargetCodeGenInfo {
unsigned SizeOfUnwindException;
public:
MIPSTargetCodeGenInfo(CodeGenTypes &CGT, bool IsO32)
: TargetCodeGenInfo(new MipsABIInfo(CGT, IsO32)),
SizeOfUnwindException(IsO32 ? 24 : 32) {}
int getDwarfEHStackPointer(CodeGen::CodeGenModule &CGM) const {
return 29;
}
void SetTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
CodeGen::CodeGenModule &CGM) const {
const FunctionDecl *FD = dyn_cast<FunctionDecl>(D);
if (!FD) return;
llvm::Function *Fn = cast<llvm::Function>(GV);
if (FD->hasAttr<Mips16Attr>()) {
Fn->addFnAttr("mips16");
}
else if (FD->hasAttr<NoMips16Attr>()) {
Fn->addFnAttr("nomips16");
}
}
bool initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
llvm::Value *Address) const;
unsigned getSizeOfUnwindException() const {
return SizeOfUnwindException;
}
};
}
void MipsABIInfo::CoerceToIntArgs(uint64_t TySize,
SmallVectorImpl<llvm::Type *> &ArgList) const {
llvm::IntegerType *IntTy =
llvm::IntegerType::get(getVMContext(), MinABIStackAlignInBytes * 8);
// Add (TySize / MinABIStackAlignInBytes) args of IntTy.
for (unsigned N = TySize / (MinABIStackAlignInBytes * 8); N; --N)
ArgList.push_back(IntTy);
// If necessary, add one more integer type to ArgList.
unsigned R = TySize % (MinABIStackAlignInBytes * 8);
if (R)
ArgList.push_back(llvm::IntegerType::get(getVMContext(), R));
}
// In N32/64, an aligned double precision floating point field is passed in
// a register.
llvm::Type* MipsABIInfo::HandleAggregates(QualType Ty, uint64_t TySize) const {
SmallVector<llvm::Type*, 8> ArgList, IntArgList;
if (IsO32) {
CoerceToIntArgs(TySize, ArgList);
return llvm::StructType::get(getVMContext(), ArgList);
}
if (Ty->isComplexType())
return CGT.ConvertType(Ty);
const RecordType *RT = Ty->getAs<RecordType>();
// Unions/vectors are passed in integer registers.
if (!RT || !RT->isStructureOrClassType()) {
CoerceToIntArgs(TySize, ArgList);
return llvm::StructType::get(getVMContext(), ArgList);
}
const RecordDecl *RD = RT->getDecl();
const ASTRecordLayout &Layout = getContext().getASTRecordLayout(RD);
assert(!(TySize % 8) && "Size of structure must be multiple of 8.");
uint64_t LastOffset = 0;
unsigned idx = 0;
llvm::IntegerType *I64 = llvm::IntegerType::get(getVMContext(), 64);
// Iterate over fields in the struct/class and check if there are any aligned
// double fields.
for (RecordDecl::field_iterator i = RD->field_begin(), e = RD->field_end();
i != e; ++i, ++idx) {
const QualType Ty = i->getType();
const BuiltinType *BT = Ty->getAs<BuiltinType>();
if (!BT || BT->getKind() != BuiltinType::Double)
continue;
uint64_t Offset = Layout.getFieldOffset(idx);
if (Offset % 64) // Ignore doubles that are not aligned.
continue;
// Add ((Offset - LastOffset) / 64) args of type i64.
for (unsigned j = (Offset - LastOffset) / 64; j > 0; --j)
ArgList.push_back(I64);
// Add double type.
ArgList.push_back(llvm::Type::getDoubleTy(getVMContext()));
LastOffset = Offset + 64;
}
CoerceToIntArgs(TySize - LastOffset, IntArgList);
ArgList.append(IntArgList.begin(), IntArgList.end());
return llvm::StructType::get(getVMContext(), ArgList);
}
llvm::Type *MipsABIInfo::getPaddingType(uint64_t Align, uint64_t Offset) const {
assert((Offset % MinABIStackAlignInBytes) == 0);
if ((Align - 1) & Offset)
return llvm::IntegerType::get(getVMContext(), MinABIStackAlignInBytes * 8);
return 0;
}
ABIArgInfo
MipsABIInfo::classifyArgumentType(QualType Ty, uint64_t &Offset) const {
uint64_t OrigOffset = Offset;
uint64_t TySize = getContext().getTypeSize(Ty);
uint64_t Align = getContext().getTypeAlign(Ty) / 8;
Align = std::min(std::max(Align, (uint64_t)MinABIStackAlignInBytes),
(uint64_t)StackAlignInBytes);
Offset = llvm::RoundUpToAlignment(Offset, Align);
Offset += llvm::RoundUpToAlignment(TySize, Align * 8) / 8;
if (isAggregateTypeForABI(Ty) || Ty->isVectorType()) {
// Ignore empty aggregates.
if (TySize == 0)
return ABIArgInfo::getIgnore();
if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, CGT)) {
Offset = OrigOffset + MinABIStackAlignInBytes;
return ABIArgInfo::getIndirect(0, RAA == CGCXXABI::RAA_DirectInMemory);
}
// If we have reached here, aggregates are passed directly by coercing to
// another structure type. Padding is inserted if the offset of the
// aggregate is unaligned.
return ABIArgInfo::getDirect(HandleAggregates(Ty, TySize), 0,
getPaddingType(Align, OrigOffset));
}
// Treat an enum type as its underlying type.
if (const EnumType *EnumTy = Ty->getAs<EnumType>())
Ty = EnumTy->getDecl()->getIntegerType();
if (Ty->isPromotableIntegerType())
return ABIArgInfo::getExtend();
return ABIArgInfo::getDirect(0, 0,
IsO32 ? 0 : getPaddingType(Align, OrigOffset));
}
llvm::Type*
MipsABIInfo::returnAggregateInRegs(QualType RetTy, uint64_t Size) const {
const RecordType *RT = RetTy->getAs<RecordType>();
SmallVector<llvm::Type*, 8> RTList;
if (RT && RT->isStructureOrClassType()) {
const RecordDecl *RD = RT->getDecl();
const ASTRecordLayout &Layout = getContext().getASTRecordLayout(RD);
unsigned FieldCnt = Layout.getFieldCount();
// N32/64 returns struct/classes in floating point registers if the
// following conditions are met:
// 1. The size of the struct/class is no larger than 128-bit.
// 2. The struct/class has one or two fields all of which are floating
// point types.
// 3. The offset of the first field is zero (this follows what gcc does).
//
// Any other composite results are returned in integer registers.
//
if (FieldCnt && (FieldCnt <= 2) && !Layout.getFieldOffset(0)) {
RecordDecl::field_iterator b = RD->field_begin(), e = RD->field_end();
for (; b != e; ++b) {
const BuiltinType *BT = b->getType()->getAs<BuiltinType>();
if (!BT || !BT->isFloatingPoint())
break;
RTList.push_back(CGT.ConvertType(b->getType()));
}
if (b == e)
return llvm::StructType::get(getVMContext(), RTList,
RD->hasAttr<PackedAttr>());
RTList.clear();
}
}
CoerceToIntArgs(Size, RTList);
return llvm::StructType::get(getVMContext(), RTList);
}
ABIArgInfo MipsABIInfo::classifyReturnType(QualType RetTy) const {
uint64_t Size = getContext().getTypeSize(RetTy);
if (RetTy->isVoidType() || Size == 0)
return ABIArgInfo::getIgnore();
if (isAggregateTypeForABI(RetTy) || RetTy->isVectorType()) {
if (isRecordReturnIndirect(RetTy, CGT))
return ABIArgInfo::getIndirect(0);
if (Size <= 128) {
if (RetTy->isAnyComplexType())
return ABIArgInfo::getDirect();
// O32 returns integer vectors in registers.
if (IsO32 && RetTy->isVectorType() && !RetTy->hasFloatingRepresentation())
return ABIArgInfo::getDirect(returnAggregateInRegs(RetTy, Size));
if (!IsO32)
return ABIArgInfo::getDirect(returnAggregateInRegs(RetTy, Size));
}
return ABIArgInfo::getIndirect(0);
}
// Treat an enum type as its underlying type.
if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
RetTy = EnumTy->getDecl()->getIntegerType();
return (RetTy->isPromotableIntegerType() ?
ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
}
void MipsABIInfo::computeInfo(CGFunctionInfo &FI) const {
ABIArgInfo &RetInfo = FI.getReturnInfo();
RetInfo = classifyReturnType(FI.getReturnType());
// Check if a pointer to an aggregate is passed as a hidden argument.
uint64_t Offset = RetInfo.isIndirect() ? MinABIStackAlignInBytes : 0;
for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end();
it != ie; ++it)
it->info = classifyArgumentType(it->type, Offset);
}
llvm::Value* MipsABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
CodeGenFunction &CGF) const {
llvm::Type *BP = CGF.Int8PtrTy;
llvm::Type *BPP = CGF.Int8PtrPtrTy;
CGBuilderTy &Builder = CGF.Builder;
llvm::Value *VAListAddrAsBPP = Builder.CreateBitCast(VAListAddr, BPP, "ap");
llvm::Value *Addr = Builder.CreateLoad(VAListAddrAsBPP, "ap.cur");
int64_t TypeAlign = getContext().getTypeAlign(Ty) / 8;
llvm::Type *PTy = llvm::PointerType::getUnqual(CGF.ConvertType(Ty));
llvm::Value *AddrTyped;
unsigned PtrWidth = getTarget().getPointerWidth(0);
llvm::IntegerType *IntTy = (PtrWidth == 32) ? CGF.Int32Ty : CGF.Int64Ty;
if (TypeAlign > MinABIStackAlignInBytes) {
llvm::Value *AddrAsInt = CGF.Builder.CreatePtrToInt(Addr, IntTy);
llvm::Value *Inc = llvm::ConstantInt::get(IntTy, TypeAlign - 1);
llvm::Value *Mask = llvm::ConstantInt::get(IntTy, -TypeAlign);
llvm::Value *Add = CGF.Builder.CreateAdd(AddrAsInt, Inc);
llvm::Value *And = CGF.Builder.CreateAnd(Add, Mask);
AddrTyped = CGF.Builder.CreateIntToPtr(And, PTy);
}
else
AddrTyped = Builder.CreateBitCast(Addr, PTy);
llvm::Value *AlignedAddr = Builder.CreateBitCast(AddrTyped, BP);
TypeAlign = std::max((unsigned)TypeAlign, MinABIStackAlignInBytes);
uint64_t Offset =
llvm::RoundUpToAlignment(CGF.getContext().getTypeSize(Ty) / 8, TypeAlign);
llvm::Value *NextAddr =
Builder.CreateGEP(AlignedAddr, llvm::ConstantInt::get(IntTy, Offset),
"ap.next");
Builder.CreateStore(NextAddr, VAListAddrAsBPP);
return AddrTyped;
}
bool
MIPSTargetCodeGenInfo::initDwarfEHRegSizeTable(CodeGen::CodeGenFunction &CGF,
llvm::Value *Address) const {
// This information comes from gcc's implementation, which seems to
// as canonical as it gets.
// Everything on MIPS is 4 bytes. Double-precision FP registers
// are aliased to pairs of single-precision FP registers.
llvm::Value *Four8 = llvm::ConstantInt::get(CGF.Int8Ty, 4);
// 0-31 are the general purpose registers, $0 - $31.
// 32-63 are the floating-point registers, $f0 - $f31.
// 64 and 65 are the multiply/divide registers, $hi and $lo.
// 66 is the (notional, I think) register for signal-handler return.
AssignToArrayRange(CGF.Builder, Address, Four8, 0, 65);
// 67-74 are the floating-point status registers, $fcc0 - $fcc7.
// They are one bit wide and ignored here.
// 80-111 are the coprocessor 0 registers, $c0r0 - $c0r31.
// (coprocessor 1 is the FP unit)
// 112-143 are the coprocessor 2 registers, $c2r0 - $c2r31.
// 144-175 are the coprocessor 3 registers, $c3r0 - $c3r31.
// 176-181 are the DSP accumulator registers.
AssignToArrayRange(CGF.Builder, Address, Four8, 80, 181);
return false;
}
//===----------------------------------------------------------------------===//
// TCE ABI Implementation (see http://tce.cs.tut.fi). Uses mostly the defaults.
// Currently subclassed only to implement custom OpenCL C function attribute
// handling.
//===----------------------------------------------------------------------===//
namespace {
class TCETargetCodeGenInfo : public DefaultTargetCodeGenInfo {
public:
TCETargetCodeGenInfo(CodeGenTypes &CGT)
: DefaultTargetCodeGenInfo(CGT) {}
virtual void SetTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
CodeGen::CodeGenModule &M) const;
};
void TCETargetCodeGenInfo::SetTargetAttributes(const Decl *D,
llvm::GlobalValue *GV,
CodeGen::CodeGenModule &M) const {
const FunctionDecl *FD = dyn_cast<FunctionDecl>(D);
if (!FD) return;
llvm::Function *F = cast<llvm::Function>(GV);
if (M.getLangOpts().OpenCL) {
if (FD->hasAttr<OpenCLKernelAttr>()) {
// OpenCL C Kernel functions are not subject to inlining
F->addFnAttr(llvm::Attribute::NoInline);
if (FD->hasAttr<ReqdWorkGroupSizeAttr>()) {
// Convert the reqd_work_group_size() attributes to metadata.
llvm::LLVMContext &Context = F->getContext();
llvm::NamedMDNode *OpenCLMetadata =
M.getModule().getOrInsertNamedMetadata("opencl.kernel_wg_size_info");
SmallVector<llvm::Value*, 5> Operands;
Operands.push_back(F);
Operands.push_back(llvm::Constant::getIntegerValue(M.Int32Ty,
llvm::APInt(32,
FD->getAttr<ReqdWorkGroupSizeAttr>()->getXDim())));
Operands.push_back(llvm::Constant::getIntegerValue(M.Int32Ty,
llvm::APInt(32,
FD->getAttr<ReqdWorkGroupSizeAttr>()->getYDim())));
Operands.push_back(llvm::Constant::getIntegerValue(M.Int32Ty,
llvm::APInt(32,
FD->getAttr<ReqdWorkGroupSizeAttr>()->getZDim())));
// Add a boolean constant operand for "required" (true) or "hint" (false)
// for implementing the work_group_size_hint attr later. Currently
// always true as the hint is not yet implemented.
Operands.push_back(llvm::ConstantInt::getTrue(Context));
OpenCLMetadata->addOperand(llvm::MDNode::get(Context, Operands));
}
}
}
}
}
//===----------------------------------------------------------------------===//
// Hexagon ABI Implementation
//===----------------------------------------------------------------------===//
namespace {
class HexagonABIInfo : public ABIInfo {
public:
HexagonABIInfo(CodeGenTypes &CGT) : ABIInfo(CGT) {}
private:
ABIArgInfo classifyReturnType(QualType RetTy) const;
ABIArgInfo classifyArgumentType(QualType RetTy) const;
virtual void computeInfo(CGFunctionInfo &FI) const;
virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
CodeGenFunction &CGF) const;
};
class HexagonTargetCodeGenInfo : public TargetCodeGenInfo {
public:
HexagonTargetCodeGenInfo(CodeGenTypes &CGT)
:TargetCodeGenInfo(new HexagonABIInfo(CGT)) {}
int getDwarfEHStackPointer(CodeGen::CodeGenModule &M) const {
return 29;
}
};
}
void HexagonABIInfo::computeInfo(CGFunctionInfo &FI) const {
FI.getReturnInfo() = classifyReturnType(FI.getReturnType());
for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end();
it != ie; ++it)
it->info = classifyArgumentType(it->type);
}
ABIArgInfo HexagonABIInfo::classifyArgumentType(QualType Ty) const {
if (!isAggregateTypeForABI(Ty)) {
// Treat an enum type as its underlying type.
if (const EnumType *EnumTy = Ty->getAs<EnumType>())
Ty = EnumTy->getDecl()->getIntegerType();
return (Ty->isPromotableIntegerType() ?
ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
}
// Ignore empty records.
if (isEmptyRecord(getContext(), Ty, true))
return ABIArgInfo::getIgnore();
if (CGCXXABI::RecordArgABI RAA = getRecordArgABI(Ty, CGT))
return ABIArgInfo::getIndirect(0, RAA == CGCXXABI::RAA_DirectInMemory);
uint64_t Size = getContext().getTypeSize(Ty);
if (Size > 64)
return ABIArgInfo::getIndirect(0, /*ByVal=*/true);
// Pass in the smallest viable integer type.
else if (Size > 32)
return ABIArgInfo::getDirect(llvm::Type::getInt64Ty(getVMContext()));
else if (Size > 16)
return ABIArgInfo::getDirect(llvm::Type::getInt32Ty(getVMContext()));
else if (Size > 8)
return ABIArgInfo::getDirect(llvm::Type::getInt16Ty(getVMContext()));
else
return ABIArgInfo::getDirect(llvm::Type::getInt8Ty(getVMContext()));
}
ABIArgInfo HexagonABIInfo::classifyReturnType(QualType RetTy) const {
if (RetTy->isVoidType())
return ABIArgInfo::getIgnore();
// Large vector types should be returned via memory.
if (RetTy->isVectorType() && getContext().getTypeSize(RetTy) > 64)
return ABIArgInfo::getIndirect(0);
if (!isAggregateTypeForABI(RetTy)) {
// Treat an enum type as its underlying type.
if (const EnumType *EnumTy = RetTy->getAs<EnumType>())
RetTy = EnumTy->getDecl()->getIntegerType();
return (RetTy->isPromotableIntegerType() ?
ABIArgInfo::getExtend() : ABIArgInfo::getDirect());
}
// Structures with either a non-trivial destructor or a non-trivial
// copy constructor are always indirect.
if (isRecordReturnIndirect(RetTy, CGT))
return ABIArgInfo::getIndirect(0, /*ByVal=*/false);
if (isEmptyRecord(getContext(), RetTy, true))
return ABIArgInfo::getIgnore();
// Aggregates <= 8 bytes are returned in r0; other aggregates
// are returned indirectly.
uint64_t Size = getContext().getTypeSize(RetTy);
if (Size <= 64) {
// Return in the smallest viable integer type.
if (Size <= 8)
return ABIArgInfo::getDirect(llvm::Type::getInt8Ty(getVMContext()));
if (Size <= 16)
return ABIArgInfo::getDirect(llvm::Type::getInt16Ty(getVMContext()));
if (Size <= 32)
return ABIArgInfo::getDirect(llvm::Type::getInt32Ty(getVMContext()));
return ABIArgInfo::getDirect(llvm::Type::getInt64Ty(getVMContext()));
}
return ABIArgInfo::getIndirect(0, /*ByVal=*/true);
}
llvm::Value *HexagonABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
CodeGenFunction &CGF) const {
// FIXME: Need to handle alignment
llvm::Type *BPP = CGF.Int8PtrPtrTy;
CGBuilderTy &Builder = CGF.Builder;
llvm::Value *VAListAddrAsBPP = Builder.CreateBitCast(VAListAddr, BPP,
"ap");
llvm::Value *Addr = Builder.CreateLoad(VAListAddrAsBPP, "ap.cur");
llvm::Type *PTy =
llvm::PointerType::getUnqual(CGF.ConvertType(Ty));
llvm::Value *AddrTyped = Builder.CreateBitCast(Addr, PTy);
uint64_t Offset =
llvm::RoundUpToAlignment(CGF.getContext().getTypeSize(Ty) / 8, 4);
llvm::Value *NextAddr =
Builder.CreateGEP(Addr, llvm::ConstantInt::get(CGF.Int32Ty, Offset),
"ap.next");
Builder.CreateStore(NextAddr, VAListAddrAsBPP);
return AddrTyped;
}
//===----------------------------------------------------------------------===//
// SPARC v9 ABI Implementation.
// Based on the SPARC Compliance Definition version 2.4.1.
//
// Function arguments a mapped to a nominal "parameter array" and promoted to
// registers depending on their type. Each argument occupies 8 or 16 bytes in
// the array, structs larger than 16 bytes are passed indirectly.
//
// One case requires special care:
//
// struct mixed {
// int i;
// float f;
// };
//
// When a struct mixed is passed by value, it only occupies 8 bytes in the
// parameter array, but the int is passed in an integer register, and the float
// is passed in a floating point register. This is represented as two arguments
// with the LLVM IR inreg attribute:
//
// declare void f(i32 inreg %i, float inreg %f)
//
// The code generator will only allocate 4 bytes from the parameter array for
// the inreg arguments. All other arguments are allocated a multiple of 8
// bytes.
//
namespace {
class SparcV9ABIInfo : public ABIInfo {
public:
SparcV9ABIInfo(CodeGenTypes &CGT) : ABIInfo(CGT) {}
private:
ABIArgInfo classifyType(QualType RetTy, unsigned SizeLimit) const;
virtual void computeInfo(CGFunctionInfo &FI) const;
virtual llvm::Value *EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
CodeGenFunction &CGF) const;
// Coercion type builder for structs passed in registers. The coercion type
// serves two purposes:
//
// 1. Pad structs to a multiple of 64 bits, so they are passed 'left-aligned'
// in registers.
// 2. Expose aligned floating point elements as first-level elements, so the
// code generator knows to pass them in floating point registers.
//
// We also compute the InReg flag which indicates that the struct contains
// aligned 32-bit floats.
//
struct CoerceBuilder {
llvm::LLVMContext &Context;
const llvm::DataLayout &DL;
SmallVector<llvm::Type*, 8> Elems;
uint64_t Size;
bool InReg;
CoerceBuilder(llvm::LLVMContext &c, const llvm::DataLayout &dl)
: Context(c), DL(dl), Size(0), InReg(false) {}
// Pad Elems with integers until Size is ToSize.
void pad(uint64_t ToSize) {
assert(ToSize >= Size && "Cannot remove elements");
if (ToSize == Size)
return;
// Finish the current 64-bit word.
uint64_t Aligned = llvm::RoundUpToAlignment(Size, 64);
if (Aligned > Size && Aligned <= ToSize) {
Elems.push_back(llvm::IntegerType::get(Context, Aligned - Size));
Size = Aligned;
}
// Add whole 64-bit words.
while (Size + 64 <= ToSize) {
Elems.push_back(llvm::Type::getInt64Ty(Context));
Size += 64;
}
// Final in-word padding.
if (Size < ToSize) {
Elems.push_back(llvm::IntegerType::get(Context, ToSize - Size));
Size = ToSize;
}
}
// Add a floating point element at Offset.
void addFloat(uint64_t Offset, llvm::Type *Ty, unsigned Bits) {
// Unaligned floats are treated as integers.
if (Offset % Bits)
return;
// The InReg flag is only required if there are any floats < 64 bits.
if (Bits < 64)
InReg = true;
pad(Offset);
Elems.push_back(Ty);
Size = Offset + Bits;
}
// Add a struct type to the coercion type, starting at Offset (in bits).
void addStruct(uint64_t Offset, llvm::StructType *StrTy) {
const llvm::StructLayout *Layout = DL.getStructLayout(StrTy);
for (unsigned i = 0, e = StrTy->getNumElements(); i != e; ++i) {
llvm::Type *ElemTy = StrTy->getElementType(i);
uint64_t ElemOffset = Offset + Layout->getElementOffsetInBits(i);
switch (ElemTy->getTypeID()) {
case llvm::Type::StructTyID:
addStruct(ElemOffset, cast<llvm::StructType>(ElemTy));
break;
case llvm::Type::FloatTyID:
addFloat(ElemOffset, ElemTy, 32);
break;
case llvm::Type::DoubleTyID:
addFloat(ElemOffset, ElemTy, 64);
break;
case llvm::Type::FP128TyID:
addFloat(ElemOffset, ElemTy, 128);
break;
case llvm::Type::PointerTyID:
if (ElemOffset % 64 == 0) {
pad(ElemOffset);
Elems.push_back(ElemTy);
Size += 64;
}
break;
default:
break;
}
}
}
// Check if Ty is a usable substitute for the coercion type.
bool isUsableType(llvm::StructType *Ty) const {
if (Ty->getNumElements() != Elems.size())
return false;
for (unsigned i = 0, e = Elems.size(); i != e; ++i)
if (Elems[i] != Ty->getElementType(i))
return false;
return true;
}
// Get the coercion type as a literal struct type.
llvm::Type *getType() const {
if (Elems.size() == 1)
return Elems.front();
else
return llvm::StructType::get(Context, Elems);
}
};
};
} // end anonymous namespace
ABIArgInfo
SparcV9ABIInfo::classifyType(QualType Ty, unsigned SizeLimit) const {
if (Ty->isVoidType())
return ABIArgInfo::getIgnore();
uint64_t Size = getContext().getTypeSize(Ty);
// Anything too big to fit in registers is passed with an explicit indirect
// pointer / sret pointer.
if (Size > SizeLimit)
return ABIArgInfo::getIndirect(0, /*ByVal=*/false);
// Treat an enum type as its underlying type.
if (const EnumType *EnumTy = Ty->getAs<EnumType>())
Ty = EnumTy->getDecl()->getIntegerType();
// Integer types smaller than a register are extended.
if (Size < 64 && Ty->isIntegerType())
return ABIArgInfo::getExtend();
// Other non-aggregates go in registers.
if (!isAggregateTypeForABI(Ty))
return ABIArgInfo::getDirect();
// This is a small aggregate type that should be passed in registers.
// Build a coercion type from the LLVM struct type.
llvm::StructType *StrTy = dyn_cast<llvm::StructType>(CGT.ConvertType(Ty));
if (!StrTy)
return ABIArgInfo::getDirect();
CoerceBuilder CB(getVMContext(), getDataLayout());
CB.addStruct(0, StrTy);
CB.pad(llvm::RoundUpToAlignment(CB.DL.getTypeSizeInBits(StrTy), 64));
// Try to use the original type for coercion.
llvm::Type *CoerceTy = CB.isUsableType(StrTy) ? StrTy : CB.getType();
if (CB.InReg)
return ABIArgInfo::getDirectInReg(CoerceTy);
else
return ABIArgInfo::getDirect(CoerceTy);
}
llvm::Value *SparcV9ABIInfo::EmitVAArg(llvm::Value *VAListAddr, QualType Ty,
CodeGenFunction &CGF) const {
ABIArgInfo AI = classifyType(Ty, 16 * 8);
llvm::Type *ArgTy = CGT.ConvertType(Ty);
if (AI.canHaveCoerceToType() && !AI.getCoerceToType())
AI.setCoerceToType(ArgTy);
llvm::Type *BPP = CGF.Int8PtrPtrTy;
CGBuilderTy &Builder = CGF.Builder;
llvm::Value *VAListAddrAsBPP = Builder.CreateBitCast(VAListAddr, BPP, "ap");
llvm::Value *Addr = Builder.CreateLoad(VAListAddrAsBPP, "ap.cur");
llvm::Type *ArgPtrTy = llvm::PointerType::getUnqual(ArgTy);
llvm::Value *ArgAddr;
unsigned Stride;
switch (AI.getKind()) {
case ABIArgInfo::Expand:
llvm_unreachable("Unsupported ABI kind for va_arg");
case ABIArgInfo::Extend:
Stride = 8;
ArgAddr = Builder
.CreateConstGEP1_32(Addr, 8 - getDataLayout().getTypeAllocSize(ArgTy),
"extend");
break;
case ABIArgInfo::Direct:
Stride = getDataLayout().getTypeAllocSize(AI.getCoerceToType());
ArgAddr = Addr;
break;
case ABIArgInfo::Indirect:
Stride = 8;
ArgAddr = Builder.CreateBitCast(Addr,
llvm::PointerType::getUnqual(ArgPtrTy),
"indirect");
ArgAddr = Builder.CreateLoad(ArgAddr, "indirect.arg");
break;
case ABIArgInfo::Ignore:
return llvm::UndefValue::get(ArgPtrTy);
}
// Update VAList.
Addr = Builder.CreateConstGEP1_32(Addr, Stride, "ap.next");
Builder.CreateStore(Addr, VAListAddrAsBPP);
return Builder.CreatePointerCast(ArgAddr, ArgPtrTy, "arg.addr");
}
void SparcV9ABIInfo::computeInfo(CGFunctionInfo &FI) const {
FI.getReturnInfo() = classifyType(FI.getReturnType(), 32 * 8);
for (CGFunctionInfo::arg_iterator it = FI.arg_begin(), ie = FI.arg_end();
it != ie; ++it)
it->info = classifyType(it->type, 16 * 8);
}
namespace {
class SparcV9TargetCodeGenInfo : public TargetCodeGenInfo {
public:
SparcV9TargetCodeGenInfo(CodeGenTypes &CGT)
: TargetCodeGenInfo(new SparcV9ABIInfo(CGT)) {}
};
} // end anonymous namespace
const TargetCodeGenInfo &CodeGenModule::getTargetCodeGenInfo() {
if (TheTargetCodeGenInfo)
return *TheTargetCodeGenInfo;
const llvm::Triple &Triple = getTarget().getTriple();
switch (Triple.getArch()) {
default:
return *(TheTargetCodeGenInfo = new DefaultTargetCodeGenInfo(Types));
case llvm::Triple::le32:
return *(TheTargetCodeGenInfo = new PNaClTargetCodeGenInfo(Types));
case llvm::Triple::mips:
case llvm::Triple::mipsel:
return *(TheTargetCodeGenInfo = new MIPSTargetCodeGenInfo(Types, true));
case llvm::Triple::mips64:
case llvm::Triple::mips64el:
return *(TheTargetCodeGenInfo = new MIPSTargetCodeGenInfo(Types, false));
case llvm::Triple::aarch64:
return *(TheTargetCodeGenInfo = new AArch64TargetCodeGenInfo(Types));
case llvm::Triple::arm:
case llvm::Triple::thumb:
{
ARMABIInfo::ABIKind Kind = ARMABIInfo::AAPCS;
if (strcmp(getTarget().getABI(), "apcs-gnu") == 0)
Kind = ARMABIInfo::APCS;
else if (CodeGenOpts.FloatABI == "hard" ||
(CodeGenOpts.FloatABI != "soft" &&
Triple.getEnvironment() == llvm::Triple::GNUEABIHF))
Kind = ARMABIInfo::AAPCS_VFP;
switch (Triple.getOS()) {
case llvm::Triple::NaCl:
return *(TheTargetCodeGenInfo =
new NaClARMTargetCodeGenInfo(Types, Kind));
default:
return *(TheTargetCodeGenInfo =
new ARMTargetCodeGenInfo(Types, Kind));
}
}
case llvm::Triple::ppc:
return *(TheTargetCodeGenInfo = new PPC32TargetCodeGenInfo(Types));
case llvm::Triple::ppc64:
if (Triple.isOSBinFormatELF())
return *(TheTargetCodeGenInfo = new PPC64_SVR4_TargetCodeGenInfo(Types));
else
return *(TheTargetCodeGenInfo = new PPC64TargetCodeGenInfo(Types));
case llvm::Triple::ppc64le:
assert(Triple.isOSBinFormatELF() && "PPC64 LE non-ELF not supported!");
return *(TheTargetCodeGenInfo = new PPC64_SVR4_TargetCodeGenInfo(Types));
case llvm::Triple::nvptx:
case llvm::Triple::nvptx64:
return *(TheTargetCodeGenInfo = new NVPTXTargetCodeGenInfo(Types));
case llvm::Triple::msp430:
return *(TheTargetCodeGenInfo = new MSP430TargetCodeGenInfo(Types));
case llvm::Triple::systemz:
return *(TheTargetCodeGenInfo = new SystemZTargetCodeGenInfo(Types));
case llvm::Triple::tce:
return *(TheTargetCodeGenInfo = new TCETargetCodeGenInfo(Types));
case llvm::Triple::x86: {
bool IsDarwinVectorABI = Triple.isOSDarwin();
bool IsSmallStructInRegABI =
X86_32TargetCodeGenInfo::isStructReturnInRegABI(Triple, CodeGenOpts);
bool IsWin32FloatStructABI = (Triple.getOS() == llvm::Triple::Win32);
if (Triple.getOS() == llvm::Triple::Win32) {
return *(TheTargetCodeGenInfo =
new WinX86_32TargetCodeGenInfo(Types,
IsDarwinVectorABI, IsSmallStructInRegABI,
IsWin32FloatStructABI,
CodeGenOpts.NumRegisterParameters));
} else {
return *(TheTargetCodeGenInfo =
new X86_32TargetCodeGenInfo(Types,
IsDarwinVectorABI, IsSmallStructInRegABI,
IsWin32FloatStructABI,
CodeGenOpts.NumRegisterParameters));
}
}
case llvm::Triple::x86_64: {
bool HasAVX = strcmp(getTarget().getABI(), "avx") == 0;
switch (Triple.getOS()) {
case llvm::Triple::Win32:
case llvm::Triple::MinGW32:
case llvm::Triple::Cygwin:
return *(TheTargetCodeGenInfo = new WinX86_64TargetCodeGenInfo(Types));
case llvm::Triple::NaCl:
return *(TheTargetCodeGenInfo = new NaClX86_64TargetCodeGenInfo(Types,
HasAVX));
default:
return *(TheTargetCodeGenInfo = new X86_64TargetCodeGenInfo(Types,
HasAVX));
}
}
case llvm::Triple::hexagon:
return *(TheTargetCodeGenInfo = new HexagonTargetCodeGenInfo(Types));
case llvm::Triple::sparcv9:
return *(TheTargetCodeGenInfo = new SparcV9TargetCodeGenInfo(Types));
}
}
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