#include "llvm/IR/DataLayout.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/DerivedTypes.h"
#include "llvm/IR/Module.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/GetElementPtrTypeIterator.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;
INITIALIZE_PASS(DataLayout, "datalayout", "Data Layout", false, true)
char DataLayout::ID = 0;
StructLayout::StructLayout(StructType *ST, const DataLayout &TD) {
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 : TD.getABITypeAlignment(Ty);
if ((StructSize & (TyAlign-1)) != 0)
StructSize = DataLayout::RoundUpAlignment(StructSize, TyAlign);
StructAlignment = std::max(TyAlign, StructAlignment);
MemberOffsets[i] = StructSize;
StructSize += TD.getTypeAllocSize(Ty); }
if (StructAlignment == 0) StructAlignment = 1;
if ((StructSize & (StructAlignment-1)) != 0)
StructSize = DataLayout::RoundUpAlignment(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 = LayoutAlignElem::get(INVALID_ALIGN, 0, 0, 0);
PointerAlignElem
PointerAlignElem::get(uint32_t addr_space, unsigned abi_align,
unsigned pref_align, uint32_t bit_width) {
assert(abi_align <= pref_align && "Preferred alignment worse than ABI!");
PointerAlignElem retval;
retval.AddressSpace = addr_space;
retval.ABIAlign = abi_align;
retval.PrefAlign = pref_align;
retval.TypeBitWidth = bit_width;
return retval;
}
bool
PointerAlignElem::operator==(const PointerAlignElem &rhs) const {
return (ABIAlign == rhs.ABIAlign
&& AddressSpace == rhs.AddressSpace
&& PrefAlign == rhs.PrefAlign
&& TypeBitWidth == rhs.TypeBitWidth);
}
const PointerAlignElem
DataLayout::InvalidPointerElem = PointerAlignElem::get(~0U, 0U, 0U, 0U);
void DataLayout::init(StringRef Desc) {
initializeDataLayoutPass(*PassRegistry::getPassRegistry());
LayoutMap = 0;
LittleEndian = false;
StackNaturalAlign = 0;
setAlignment(INTEGER_ALIGN, 1, 1, 1); setAlignment(INTEGER_ALIGN, 1, 1, 8); setAlignment(INTEGER_ALIGN, 2, 2, 16); setAlignment(INTEGER_ALIGN, 4, 4, 32); setAlignment(INTEGER_ALIGN, 4, 8, 64); setAlignment(FLOAT_ALIGN, 2, 2, 16); setAlignment(FLOAT_ALIGN, 4, 4, 32); setAlignment(FLOAT_ALIGN, 8, 8, 64); setAlignment(FLOAT_ALIGN, 16, 16, 128); setAlignment(VECTOR_ALIGN, 8, 8, 64); setAlignment(VECTOR_ALIGN, 16, 16, 128); setAlignment(AGGREGATE_ALIGN, 0, 8, 0); 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);
assert((!Split.second.empty() || Split.first == Str) &&
"a trailing separator is not allowed");
return Split;
}
static unsigned getInt(StringRef R) {
unsigned Result;
bool error = R.getAsInteger(10, Result); (void)error;
assert(!error && "not a number, or does not fit in an unsigned int");
return Result;
}
static unsigned inBytes(unsigned Bits) {
assert(Bits % 8 == 0 && "number of bits must be a byte width multiple");
return Bits / 8;
}
void DataLayout::parseSpecifier(StringRef 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 'E':
LittleEndian = false;
break;
case 'e':
LittleEndian = true;
break;
case 'p': {
unsigned AddrSpace = Tok.empty() ? 0 : getInt(Tok);
assert(AddrSpace < 1 << 24 &&
"Invalid address space, must be a 24bit integer");
Split = split(Rest, ':');
unsigned PointerMemSize = inBytes(getInt(Tok));
Split = split(Rest, ':');
unsigned PointerABIAlign = inBytes(getInt(Tok));
unsigned PointerPrefAlign = PointerABIAlign;
if (!Rest.empty()) {
Split = split(Rest, ':');
PointerPrefAlign = inBytes(getInt(Tok));
}
setPointerAlignment(AddrSpace, PointerABIAlign, PointerPrefAlign,
PointerMemSize);
break;
}
case 'i':
case 'v':
case 'f':
case 'a':
case 's': {
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;
case 's': AlignType = STACK_ALIGN; break;
}
unsigned Size = Tok.empty() ? 0 : getInt(Tok);
Split = split(Rest, ':');
unsigned ABIAlign = inBytes(getInt(Tok));
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);
assert(Width != 0 && "width must be non-zero");
LegalIntWidths.push_back(Width);
if (Rest.empty())
break;
Split = split(Rest, ':');
}
break;
case 'S': { StackNaturalAlign = inBytes(getInt(Tok));
break;
}
default:
llvm_unreachable("Unknown specifier in datalayout string");
break;
}
}
}
DataLayout::DataLayout() : ImmutablePass(ID) {
report_fatal_error("Bad DataLayout ctor used. "
"Tool did not specify a DataLayout to use?");
}
DataLayout::DataLayout(const Module *M)
: ImmutablePass(ID) {
init(M->getDataLayout());
}
void
DataLayout::setAlignment(AlignTypeEnum align_type, unsigned abi_align,
unsigned pref_align, uint32_t bit_width) {
assert(abi_align <= pref_align && "Preferred alignment worse than ABI!");
assert(pref_align < (1 << 16) && "Alignment doesn't fit in bitfield");
assert(bit_width < (1 << 24) && "Bit width doesn't fit in bitfield");
for (unsigned i = 0, e = Alignments.size(); i != e; ++i) {
if (Alignments[i].AlignType == (unsigned)align_type &&
Alignments[i].TypeBitWidth == bit_width) {
Alignments[i].ABIAlign = abi_align;
Alignments[i].PrefAlign = pref_align;
return;
}
}
Alignments.push_back(LayoutAlignElem::get(align_type, abi_align,
pref_align, bit_width));
}
void
DataLayout::setPointerAlignment(uint32_t addr_space, unsigned abi_align,
unsigned pref_align, uint32_t bit_width) {
assert(abi_align <= pref_align && "Preferred alignment worse than ABI!");
DenseMap<unsigned,PointerAlignElem>::iterator val = Pointers.find(addr_space);
if (val == Pointers.end()) {
Pointers[addr_space] = PointerAlignElem::get(addr_space,
abi_align, pref_align, bit_width);
} else {
val->second.ABIAlign = abi_align;
val->second.PrefAlign = pref_align;
val->second.TypeBitWidth = bit_width;
}
}
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 {
assert(AlignType == VECTOR_ALIGN && "Unknown alignment type!");
unsigned Align = getTypeAllocSize(cast<VectorType>(Ty)->getElementType());
Align *= cast<VectorType>(Ty)->getNumElements();
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:
virtual ~StructLayoutMap() {
for (LayoutInfoTy::iterator I = LayoutInfo.begin(), E = LayoutInfo.end();
I != E; ++I) {
StructLayout *Value = I->second;
Value->~StructLayout();
free(Value);
}
}
StructLayout *&operator[](StructType *STy) {
return LayoutInfo[STy];
}
virtual void dump() const {}
};
}
DataLayout::~DataLayout() {
delete static_cast<StructLayoutMap*>(LayoutMap);
}
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;
}
std::string DataLayout::getStringRepresentation() const {
std::string Result;
raw_string_ostream OS(Result);
OS << (LittleEndian ? "e" : "E");
SmallVector<unsigned, 8> addrSpaces;
for (DenseMap<unsigned, PointerAlignElem>::const_iterator
pib = Pointers.begin(), pie = Pointers.end();
pib != pie; ++pib) {
addrSpaces.push_back(pib->first);
}
std::sort(addrSpaces.begin(), addrSpaces.end());
for (SmallVector<unsigned, 8>::iterator asb = addrSpaces.begin(),
ase = addrSpaces.end(); asb != ase; ++asb) {
const PointerAlignElem &PI = Pointers.find(*asb)->second;
OS << "-p";
if (PI.AddressSpace) {
OS << PI.AddressSpace;
}
OS << ":" << PI.TypeBitWidth*8 << ':' << PI.ABIAlign*8
<< ':' << PI.PrefAlign*8;
}
OS << "-S" << StackNaturalAlign*8;
for (unsigned i = 0, e = Alignments.size(); i != e; ++i) {
const LayoutAlignElem &AI = Alignments[i];
OS << '-' << (char)AI.AlignType << AI.TypeBitWidth << ':'
<< AI.ABIAlign*8 << ':' << AI.PrefAlign*8;
}
if (!LegalIntWidths.empty()) {
OS << "-n" << (unsigned)LegalIntWidths[0];
for (unsigned i = 1, e = LegalIntWidths.size(); i != e; ++i)
OS << ':' << (unsigned)LegalIntWidths[i];
}
return OS.str();
}
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 = dyn_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, 0);
}
unsigned DataLayout::getCallFrameTypeAlignment(Type *Ty) const {
for (unsigned i = 0, e = Alignments.size(); i != e; ++i)
if (Alignments[i].AlignType == STACK_ALIGN)
return Alignments[i].ABIAlign;
return getABITypeAlignment(Ty);
}
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 = getTypeSizeInBits(Ty->getScalarType());
IntegerType *IntTy = IntegerType::get(Ty->getContext(), NumBits);
if (VectorType *VecTy = dyn_cast<VectorType>(Ty))
return VectorType::get(IntTy, VecTy->getNumElements());
return IntTy;
}
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));
}