#include "llvm/IR/DataLayout.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/Triple.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/DerivedTypes.h"
#include "llvm/IR/GetElementPtrTypeIterator.h"
#include "llvm/IR/Module.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/ManagedStatic.h"
#include "llvm/Support/MathExtras.h"
#include "llvm/Support/Mutex.h"
#include "llvm/Support/raw_ostream.h"
#include <algorithm>
#include <cstdlib>
using namespace llvm;
StructLayout::StructLayout(StructType *ST, const DataLayout &DL) {
assert(!ST->isOpaque() && "Cannot get layout of opaque structs");
StructAlignment = 0;
StructSize = 0;
NumElements = ST->getNumElements();
for (unsigned i = 0, e = NumElements; i != e; ++i) {
Type *Ty = ST->getElementType(i);
unsigned TyAlign = ST->isPacked() ? 1 : DL.getABITypeAlignment(Ty);
if ((StructSize & (TyAlign-1)) != 0)
StructSize = RoundUpToAlignment(StructSize, TyAlign);
StructAlignment = std::max(TyAlign, StructAlignment);
MemberOffsets[i] = StructSize;
StructSize += DL.getTypeAllocSize(Ty); }
if (StructAlignment == 0) StructAlignment = 1;
if ((StructSize & (StructAlignment-1)) != 0)
StructSize = RoundUpToAlignment(StructSize, StructAlignment);
}
unsigned StructLayout::getElementContainingOffset(uint64_t Offset) const {
const uint64_t *SI =
std::upper_bound(&MemberOffsets[0], &MemberOffsets[NumElements], Offset);
assert(SI != &MemberOffsets[0] && "Offset not in structure type!");
--SI;
assert(*SI <= Offset && "upper_bound didn't work");
assert((SI == &MemberOffsets[0] || *(SI-1) <= Offset) &&
(SI+1 == &MemberOffsets[NumElements] || *(SI+1) > Offset) &&
"Upper bound didn't work!");
return SI-&MemberOffsets[0];
}
LayoutAlignElem
LayoutAlignElem::get(AlignTypeEnum align_type, unsigned abi_align,
unsigned pref_align, uint32_t bit_width) {
assert(abi_align <= pref_align && "Preferred alignment worse than ABI!");
LayoutAlignElem retval;
retval.AlignType = align_type;
retval.ABIAlign = abi_align;
retval.PrefAlign = pref_align;
retval.TypeBitWidth = bit_width;
return retval;
}
bool
LayoutAlignElem::operator==(const LayoutAlignElem &rhs) const {
return (AlignType == rhs.AlignType
&& ABIAlign == rhs.ABIAlign
&& PrefAlign == rhs.PrefAlign
&& TypeBitWidth == rhs.TypeBitWidth);
}
const LayoutAlignElem
DataLayout::InvalidAlignmentElem = { INVALID_ALIGN, 0, 0, 0 };
PointerAlignElem
PointerAlignElem::get(uint32_t AddressSpace, unsigned ABIAlign,
unsigned PrefAlign, uint32_t TypeByteWidth) {
assert(ABIAlign <= PrefAlign && "Preferred alignment worse than ABI!");
PointerAlignElem retval;
retval.AddressSpace = AddressSpace;
retval.ABIAlign = ABIAlign;
retval.PrefAlign = PrefAlign;
retval.TypeByteWidth = TypeByteWidth;
return retval;
}
bool
PointerAlignElem::operator==(const PointerAlignElem &rhs) const {
return (ABIAlign == rhs.ABIAlign
&& AddressSpace == rhs.AddressSpace
&& PrefAlign == rhs.PrefAlign
&& TypeByteWidth == rhs.TypeByteWidth);
}
const PointerAlignElem
DataLayout::InvalidPointerElem = { 0U, 0U, 0U, ~0U };
const char *DataLayout::getManglingComponent(const Triple &T) {
if (T.isOSBinFormatMachO())
return "-m:o";
if (T.isOSWindows() && T.isOSBinFormatCOFF())
return T.getArch() == Triple::x86 ? "-m:x" : "-m:w";
return "-m:e";
}
static const LayoutAlignElem DefaultAlignments[] = {
{ INTEGER_ALIGN, 1, 1, 1 }, { INTEGER_ALIGN, 8, 1, 1 }, { INTEGER_ALIGN, 16, 2, 2 }, { INTEGER_ALIGN, 32, 4, 4 }, { INTEGER_ALIGN, 64, 4, 8 }, { FLOAT_ALIGN, 16, 2, 2 }, { FLOAT_ALIGN, 32, 4, 4 }, { FLOAT_ALIGN, 64, 8, 8 }, { FLOAT_ALIGN, 128, 16, 16 }, { VECTOR_ALIGN, 64, 8, 8 }, { VECTOR_ALIGN, 128, 16, 16 }, { AGGREGATE_ALIGN, 0, 0, 8 } };
void DataLayout::reset(StringRef Desc) {
clear();
LayoutMap = nullptr;
BigEndian = false;
StackNaturalAlign = 0;
ManglingMode = MM_None;
for (const LayoutAlignElem &E : DefaultAlignments) {
setAlignment((AlignTypeEnum)E.AlignType, E.ABIAlign, E.PrefAlign,
E.TypeBitWidth);
}
setPointerAlignment(0, 8, 8, 8);
parseSpecifier(Desc);
}
static std::pair<StringRef, StringRef> split(StringRef Str, char Separator) {
assert(!Str.empty() && "parse error, string can't be empty here");
std::pair<StringRef, StringRef> Split = Str.split(Separator);
if (Split.second.empty() && Split.first != Str)
report_fatal_error("Trailing separator in datalayout string");
if (!Split.second.empty() && Split.first.empty())
report_fatal_error("Expected token before separator in datalayout string");
return Split;
}
static unsigned getInt(StringRef R) {
unsigned Result;
bool error = R.getAsInteger(10, Result); (void)error;
if (error)
report_fatal_error("not a number, or does not fit in an unsigned int");
return Result;
}
static unsigned inBytes(unsigned Bits) {
if (Bits % 8)
report_fatal_error("number of bits must be a byte width multiple");
return Bits / 8;
}
void DataLayout::parseSpecifier(StringRef Desc) {
StringRepresentation = Desc;
while (!Desc.empty()) {
std::pair<StringRef, StringRef> Split = split(Desc, '-');
Desc = Split.second;
Split = split(Split.first, ':');
StringRef &Tok = Split.first; StringRef &Rest = Split.second;
char Specifier = Tok.front();
Tok = Tok.substr(1);
switch (Specifier) {
case 's':
break;
case 'E':
BigEndian = true;
break;
case 'e':
BigEndian = false;
break;
case 'p': {
unsigned AddrSpace = Tok.empty() ? 0 : getInt(Tok);
if (!isUInt<24>(AddrSpace))
report_fatal_error("Invalid address space, must be a 24bit integer");
if (Rest.empty())
report_fatal_error(
"Missing size specification for pointer in datalayout string");
Split = split(Rest, ':');
unsigned PointerMemSize = inBytes(getInt(Tok));
if (!PointerMemSize)
report_fatal_error("Invalid pointer size of 0 bytes");
if (Rest.empty())
report_fatal_error(
"Missing alignment specification for pointer in datalayout string");
Split = split(Rest, ':');
unsigned PointerABIAlign = inBytes(getInt(Tok));
if (!isPowerOf2_64(PointerABIAlign))
report_fatal_error(
"Pointer ABI alignment must be a power of 2");
unsigned PointerPrefAlign = PointerABIAlign;
if (!Rest.empty()) {
Split = split(Rest, ':');
PointerPrefAlign = inBytes(getInt(Tok));
if (!isPowerOf2_64(PointerPrefAlign))
report_fatal_error(
"Pointer preferred alignment must be a power of 2");
}
setPointerAlignment(AddrSpace, PointerABIAlign, PointerPrefAlign,
PointerMemSize);
break;
}
case 'i':
case 'v':
case 'f':
case 'a': {
AlignTypeEnum AlignType;
switch (Specifier) {
default:
case 'i': AlignType = INTEGER_ALIGN; break;
case 'v': AlignType = VECTOR_ALIGN; break;
case 'f': AlignType = FLOAT_ALIGN; break;
case 'a': AlignType = AGGREGATE_ALIGN; break;
}
unsigned Size = Tok.empty() ? 0 : getInt(Tok);
if (AlignType == AGGREGATE_ALIGN && Size != 0)
report_fatal_error(
"Sized aggregate specification in datalayout string");
if (Rest.empty())
report_fatal_error(
"Missing alignment specification in datalayout string");
Split = split(Rest, ':');
unsigned ABIAlign = inBytes(getInt(Tok));
if (AlignType != AGGREGATE_ALIGN && !ABIAlign)
report_fatal_error(
"ABI alignment specification must be >0 for non-aggregate types");
unsigned PrefAlign = ABIAlign;
if (!Rest.empty()) {
Split = split(Rest, ':');
PrefAlign = inBytes(getInt(Tok));
}
setAlignment(AlignType, ABIAlign, PrefAlign, Size);
break;
}
case 'n': for (;;) {
unsigned Width = getInt(Tok);
if (Width == 0)
report_fatal_error(
"Zero width native integer type in datalayout string");
LegalIntWidths.push_back(Width);
if (Rest.empty())
break;
Split = split(Rest, ':');
}
break;
case 'S': { StackNaturalAlign = inBytes(getInt(Tok));
break;
}
case 'm':
if (!Tok.empty())
report_fatal_error("Unexpected trailing characters after mangling specifier in datalayout string");
if (Rest.empty())
report_fatal_error("Expected mangling specifier in datalayout string");
if (Rest.size() > 1)
report_fatal_error("Unknown mangling specifier in datalayout string");
switch(Rest[0]) {
default:
report_fatal_error("Unknown mangling in datalayout string");
case 'e':
ManglingMode = MM_ELF;
break;
case 'o':
ManglingMode = MM_MachO;
break;
case 'm':
ManglingMode = MM_Mips;
break;
case 'w':
ManglingMode = MM_WinCOFF;
break;
case 'x':
ManglingMode = MM_WinCOFFX86;
break;
}
break;
default:
report_fatal_error("Unknown specifier in datalayout string");
break;
}
}
}
DataLayout::DataLayout(const Module *M) : LayoutMap(nullptr) {
init(M);
}
void DataLayout::init(const Module *M) { *this = M->getDataLayout(); }
bool DataLayout::operator==(const DataLayout &Other) const {
bool Ret = BigEndian == Other.BigEndian &&
StackNaturalAlign == Other.StackNaturalAlign &&
ManglingMode == Other.ManglingMode &&
LegalIntWidths == Other.LegalIntWidths &&
Alignments == Other.Alignments && Pointers == Other.Pointers;
return Ret;
}
void
DataLayout::setAlignment(AlignTypeEnum align_type, unsigned abi_align,
unsigned pref_align, uint32_t bit_width) {
if (!isUInt<24>(bit_width))
report_fatal_error("Invalid bit width, must be a 24bit integer");
if (!isUInt<16>(abi_align))
report_fatal_error("Invalid ABI alignment, must be a 16bit integer");
if (!isUInt<16>(pref_align))
report_fatal_error("Invalid preferred alignment, must be a 16bit integer");
if (abi_align != 0 && !isPowerOf2_64(abi_align))
report_fatal_error("Invalid ABI alignment, must be a power of 2");
if (pref_align != 0 && !isPowerOf2_64(pref_align))
report_fatal_error("Invalid preferred alignment, must be a power of 2");
if (pref_align < abi_align)
report_fatal_error(
"Preferred alignment cannot be less than the ABI alignment");
for (LayoutAlignElem &Elem : Alignments) {
if (Elem.AlignType == (unsigned)align_type &&
Elem.TypeBitWidth == bit_width) {
Elem.ABIAlign = abi_align;
Elem.PrefAlign = pref_align;
return;
}
}
Alignments.push_back(LayoutAlignElem::get(align_type, abi_align,
pref_align, bit_width));
}
DataLayout::PointersTy::iterator
DataLayout::findPointerLowerBound(uint32_t AddressSpace) {
return std::lower_bound(Pointers.begin(), Pointers.end(), AddressSpace,
[](const PointerAlignElem &A, uint32_t AddressSpace) {
return A.AddressSpace < AddressSpace;
});
}
void DataLayout::setPointerAlignment(uint32_t AddrSpace, unsigned ABIAlign,
unsigned PrefAlign,
uint32_t TypeByteWidth) {
if (PrefAlign < ABIAlign)
report_fatal_error(
"Preferred alignment cannot be less than the ABI alignment");
PointersTy::iterator I = findPointerLowerBound(AddrSpace);
if (I == Pointers.end() || I->AddressSpace != AddrSpace) {
Pointers.insert(I, PointerAlignElem::get(AddrSpace, ABIAlign, PrefAlign,
TypeByteWidth));
} else {
I->ABIAlign = ABIAlign;
I->PrefAlign = PrefAlign;
I->TypeByteWidth = TypeByteWidth;
}
}
unsigned DataLayout::getAlignmentInfo(AlignTypeEnum AlignType,
uint32_t BitWidth, bool ABIInfo,
Type *Ty) const {
int BestMatchIdx = -1;
int LargestInt = -1;
for (unsigned i = 0, e = Alignments.size(); i != e; ++i) {
if (Alignments[i].AlignType == (unsigned)AlignType &&
Alignments[i].TypeBitWidth == BitWidth)
return ABIInfo ? Alignments[i].ABIAlign : Alignments[i].PrefAlign;
if (AlignType == INTEGER_ALIGN &&
Alignments[i].AlignType == INTEGER_ALIGN) {
if (Alignments[i].TypeBitWidth > BitWidth && (BestMatchIdx == -1 ||
Alignments[i].TypeBitWidth < Alignments[BestMatchIdx].TypeBitWidth))
BestMatchIdx = i;
if (LargestInt == -1 ||
Alignments[i].TypeBitWidth > Alignments[LargestInt].TypeBitWidth)
LargestInt = i;
}
}
if (BestMatchIdx == -1) {
if (AlignType == INTEGER_ALIGN) {
BestMatchIdx = LargestInt;
} else if (AlignType == VECTOR_ALIGN) {
unsigned Align = getTypeAllocSize(cast<VectorType>(Ty)->getElementType());
Align *= cast<VectorType>(Ty)->getNumElements();
if (Align & (Align-1))
Align = NextPowerOf2(Align);
return Align;
}
}
if (BestMatchIdx == -1) {
unsigned Align = getTypeStoreSize(Ty);
if (Align & (Align-1))
Align = NextPowerOf2(Align);
return Align;
}
return ABIInfo ? Alignments[BestMatchIdx].ABIAlign
: Alignments[BestMatchIdx].PrefAlign;
}
namespace {
class StructLayoutMap {
typedef DenseMap<StructType*, StructLayout*> LayoutInfoTy;
LayoutInfoTy LayoutInfo;
public:
~StructLayoutMap() {
for (const auto &I : LayoutInfo) {
StructLayout *Value = I.second;
Value->~StructLayout();
free(Value);
}
}
StructLayout *&operator[](StructType *STy) {
return LayoutInfo[STy];
}
};
}
void DataLayout::clear() {
LegalIntWidths.clear();
Alignments.clear();
Pointers.clear();
delete static_cast<StructLayoutMap *>(LayoutMap);
LayoutMap = nullptr;
}
DataLayout::~DataLayout() {
clear();
}
const StructLayout *DataLayout::getStructLayout(StructType *Ty) const {
if (!LayoutMap)
LayoutMap = new StructLayoutMap();
StructLayoutMap *STM = static_cast<StructLayoutMap*>(LayoutMap);
StructLayout *&SL = (*STM)[Ty];
if (SL) return SL;
int NumElts = Ty->getNumElements();
StructLayout *L =
(StructLayout *)malloc(sizeof(StructLayout)+(NumElts-1) * sizeof(uint64_t));
SL = L;
new (L) StructLayout(Ty, *this);
return L;
}
unsigned DataLayout::getPointerABIAlignment(unsigned AS) const {
PointersTy::const_iterator I = findPointerLowerBound(AS);
if (I == Pointers.end() || I->AddressSpace != AS) {
I = findPointerLowerBound(0);
assert(I->AddressSpace == 0);
}
return I->ABIAlign;
}
unsigned DataLayout::getPointerPrefAlignment(unsigned AS) const {
PointersTy::const_iterator I = findPointerLowerBound(AS);
if (I == Pointers.end() || I->AddressSpace != AS) {
I = findPointerLowerBound(0);
assert(I->AddressSpace == 0);
}
return I->PrefAlign;
}
unsigned DataLayout::getPointerSize(unsigned AS) const {
PointersTy::const_iterator I = findPointerLowerBound(AS);
if (I == Pointers.end() || I->AddressSpace != AS) {
I = findPointerLowerBound(0);
assert(I->AddressSpace == 0);
}
return I->TypeByteWidth;
}
unsigned DataLayout::getPointerTypeSizeInBits(Type *Ty) const {
assert(Ty->isPtrOrPtrVectorTy() &&
"This should only be called with a pointer or pointer vector type");
if (Ty->isPointerTy())
return getTypeSizeInBits(Ty);
return getTypeSizeInBits(Ty->getScalarType());
}
unsigned DataLayout::getAlignment(Type *Ty, bool abi_or_pref) const {
int AlignType = -1;
assert(Ty->isSized() && "Cannot getTypeInfo() on a type that is unsized!");
switch (Ty->getTypeID()) {
case Type::LabelTyID:
return (abi_or_pref
? getPointerABIAlignment(0)
: getPointerPrefAlignment(0));
case Type::PointerTyID: {
unsigned AS = cast<PointerType>(Ty)->getAddressSpace();
return (abi_or_pref
? getPointerABIAlignment(AS)
: getPointerPrefAlignment(AS));
}
case Type::ArrayTyID:
return getAlignment(cast<ArrayType>(Ty)->getElementType(), abi_or_pref);
case Type::StructTyID: {
if (cast<StructType>(Ty)->isPacked() && abi_or_pref)
return 1;
const StructLayout *Layout = getStructLayout(cast<StructType>(Ty));
unsigned Align = getAlignmentInfo(AGGREGATE_ALIGN, 0, abi_or_pref, Ty);
return std::max(Align, Layout->getAlignment());
}
case Type::IntegerTyID:
AlignType = INTEGER_ALIGN;
break;
case Type::HalfTyID:
case Type::FloatTyID:
case Type::DoubleTyID:
case Type::PPC_FP128TyID:
case Type::FP128TyID:
case Type::X86_FP80TyID:
AlignType = FLOAT_ALIGN;
break;
case Type::X86_MMXTyID:
case Type::VectorTyID:
AlignType = VECTOR_ALIGN;
break;
default:
llvm_unreachable("Bad type for getAlignment!!!");
}
return getAlignmentInfo((AlignTypeEnum)AlignType, getTypeSizeInBits(Ty),
abi_or_pref, Ty);
}
unsigned DataLayout::getABITypeAlignment(Type *Ty) const {
return getAlignment(Ty, true);
}
unsigned DataLayout::getABIIntegerTypeAlignment(unsigned BitWidth) const {
return getAlignmentInfo(INTEGER_ALIGN, BitWidth, true, nullptr);
}
unsigned DataLayout::getPrefTypeAlignment(Type *Ty) const {
return getAlignment(Ty, false);
}
unsigned DataLayout::getPreferredTypeAlignmentShift(Type *Ty) const {
unsigned Align = getPrefTypeAlignment(Ty);
assert(!(Align & (Align-1)) && "Alignment is not a power of two!");
return Log2_32(Align);
}
IntegerType *DataLayout::getIntPtrType(LLVMContext &C,
unsigned AddressSpace) const {
return IntegerType::get(C, getPointerSizeInBits(AddressSpace));
}
Type *DataLayout::getIntPtrType(Type *Ty) const {
assert(Ty->isPtrOrPtrVectorTy() &&
"Expected a pointer or pointer vector type.");
unsigned NumBits = getPointerTypeSizeInBits(Ty);
IntegerType *IntTy = IntegerType::get(Ty->getContext(), NumBits);
if (VectorType *VecTy = dyn_cast<VectorType>(Ty))
return VectorType::get(IntTy, VecTy->getNumElements());
return IntTy;
}
Type *DataLayout::getSmallestLegalIntType(LLVMContext &C, unsigned Width) const {
for (unsigned LegalIntWidth : LegalIntWidths)
if (Width <= LegalIntWidth)
return Type::getIntNTy(C, LegalIntWidth);
return nullptr;
}
unsigned DataLayout::getLargestLegalIntTypeSize() const {
auto Max = std::max_element(LegalIntWidths.begin(), LegalIntWidths.end());
return Max != LegalIntWidths.end() ? *Max : 0;
}
uint64_t DataLayout::getIndexedOffset(Type *ptrTy,
ArrayRef<Value *> Indices) const {
Type *Ty = ptrTy;
assert(Ty->isPointerTy() && "Illegal argument for getIndexedOffset()");
uint64_t Result = 0;
generic_gep_type_iterator<Value* const*>
TI = gep_type_begin(ptrTy, Indices);
for (unsigned CurIDX = 0, EndIDX = Indices.size(); CurIDX != EndIDX;
++CurIDX, ++TI) {
if (StructType *STy = dyn_cast<StructType>(*TI)) {
assert(Indices[CurIDX]->getType() ==
Type::getInt32Ty(ptrTy->getContext()) &&
"Illegal struct idx");
unsigned FieldNo = cast<ConstantInt>(Indices[CurIDX])->getZExtValue();
const StructLayout *Layout = getStructLayout(STy);
Result += Layout->getElementOffset(FieldNo);
Ty = STy->getElementType(FieldNo);
} else {
Ty = cast<SequentialType>(Ty)->getElementType();
if (int64_t arrayIdx = cast<ConstantInt>(Indices[CurIDX])->getSExtValue())
Result += (uint64_t)arrayIdx * getTypeAllocSize(Ty);
}
}
return Result;
}
unsigned DataLayout::getPreferredAlignment(const GlobalVariable *GV) const {
Type *ElemType = GV->getType()->getElementType();
unsigned Alignment = getPrefTypeAlignment(ElemType);
unsigned GVAlignment = GV->getAlignment();
if (GVAlignment >= Alignment) {
Alignment = GVAlignment;
} else if (GVAlignment != 0) {
Alignment = std::max(GVAlignment, getABITypeAlignment(ElemType));
}
if (GV->hasInitializer() && GVAlignment == 0) {
if (Alignment < 16) {
if (getTypeSizeInBits(ElemType) > 128)
Alignment = 16; }
}
return Alignment;
}
unsigned DataLayout::getPreferredAlignmentLog(const GlobalVariable *GV) const {
return Log2_32(getPreferredAlignment(GV));
}