6502/llvm-6502
1
0
Fork 0
mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2024-07-19 03:29:22 +00:00
Code Issues Projects Releases Wiki Activity
8c541bcc56
llvm-6502/lib/Target/TargetData.cpp
Reid Spencer d2a988caad Although targets are not required to support integers > 64bits, TargetData 
must in order for backends that do want to support large integer types to be
able to function. Consequently, don't assert if the bitwidth > 64 bits
when computing the size and alignment. Instead, compute the size by rounding
up to the next even number of bytes for the size. Compute the alignment
as the same as the LongABIAlignment. These provide reasonable defaults
that the target can override.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@33943 91177308-0d34-0410-b5e6-96231b3b80d8
2007-02-05 23:51:43 +00:00

510 lines
18 KiB
C++
Raw Blame History

//===-- TargetData.cpp - Data size & alignment routines --------------------==//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by the LLVM research group and is distributed under
// the University of Illinois Open Source License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines target properties related to datatype size/offset/alignment
// information.
//
// This structure should be created once, filled in if the defaults are not
// correct and then passed around by const&. None of the members functions
// require modification to the object.
//
//===----------------------------------------------------------------------===//
#include "llvm/Target/TargetData.h"
#include "llvm/Module.h"
#include "llvm/DerivedTypes.h"
#include "llvm/Constants.h"
#include "llvm/Support/GetElementPtrTypeIterator.h"
#include "llvm/Support/MathExtras.h"
#include "llvm/ADT/StringExtras.h"
#include <algorithm>
#include <cstdlib>
#include <sstream>
using namespace llvm;
// Handle the Pass registration stuff necessary to use TargetData's.
namespace {
// Register the default SparcV9 implementation...
RegisterPass<TargetData> X("targetdata", "Target Data Layout");
}
static inline void getTypeInfoABI(const Type *Ty, const TargetData *TD,
uint64_t &Size, unsigned char &Alignment);
static inline void getTypeInfoPref(const Type *Ty, const TargetData *TD,
uint64_t &Size, unsigned char &Alignment);
//===----------------------------------------------------------------------===//
// Support for StructLayout
//===----------------------------------------------------------------------===//
StructLayout::StructLayout(const StructType *ST, const TargetData &TD) {
StructAlignment = 0;
StructSize = 0;
// Loop over each of the elements, placing them in memory...
for (StructType::element_iterator TI = ST->element_begin(),
TE = ST->element_end(); TI != TE; ++TI) {
const Type *Ty = *TI;
unsigned char A;
unsigned TyAlign;
uint64_t TySize;
getTypeInfoABI(Ty, &TD, TySize, A);
TyAlign = ST->isPacked() ? 1 : A;
// Add padding if necessary to make the data element aligned properly...
if (StructSize % TyAlign != 0)
StructSize = (StructSize/TyAlign + 1) * TyAlign; // Add padding...
// Keep track of maximum alignment constraint
StructAlignment = std::max(TyAlign, StructAlignment);
MemberOffsets.push_back(StructSize);
StructSize += TySize; // Consume space for this data item
}
// Empty structures have alignment of 1 byte.
if (StructAlignment == 0) StructAlignment = 1;
// Add padding to the end of the struct so that it could be put in an array
// and all array elements would be aligned correctly.
if (StructSize % StructAlignment != 0)
StructSize = (StructSize/StructAlignment + 1) * StructAlignment;
}
/// getElementContainingOffset - Given a valid offset into the structure,
/// return the structure index that contains it.
unsigned StructLayout::getElementContainingOffset(uint64_t Offset) const {
std::vector<uint64_t>::const_iterator SI =
std::upper_bound(MemberOffsets.begin(), MemberOffsets.end(), Offset);
assert(SI != MemberOffsets.begin() && "Offset not in structure type!");
--SI;
assert(*SI <= Offset && "upper_bound didn't work");
assert((SI == MemberOffsets.begin() || *(SI-1) < Offset) &&
(SI+1 == MemberOffsets.end() || *(SI+1) > Offset) &&
"Upper bound didn't work!");
return SI-MemberOffsets.begin();
}
//===----------------------------------------------------------------------===//
// TargetData Class Implementation
//===----------------------------------------------------------------------===//
void TargetData::init(const std::string &TargetDescription) {
std::string temp = TargetDescription;
LittleEndian = false;
PointerMemSize = 8;
PointerABIAlignment = 8;
DoubleABIAlignment = 0;
FloatABIAlignment = 4;
LongABIAlignment = 0;
IntABIAlignment = 4;
ShortABIAlignment = 2;
ByteABIAlignment = 1;
BoolABIAlignment = 1;
BoolPrefAlignment = BoolABIAlignment;
BytePrefAlignment = ByteABIAlignment;
ShortPrefAlignment = ShortABIAlignment;
IntPrefAlignment = IntABIAlignment;
LongPrefAlignment = 8;
FloatPrefAlignment = FloatABIAlignment;
DoublePrefAlignment = 8;
PointerPrefAlignment = PointerABIAlignment;
AggMinPrefAlignment = 0;
while (!temp.empty()) {
std::string token = getToken(temp, "-");
char signal = getToken(token, ":")[0];
switch(signal) {
case 'E':
LittleEndian = false;
break;
case 'e':
LittleEndian = true;
break;
case 'p':
PointerMemSize = atoi(getToken(token,":").c_str()) / 8;
PointerABIAlignment = atoi(getToken(token,":").c_str()) / 8;
PointerPrefAlignment = atoi(getToken(token,":").c_str()) / 8;
if (PointerPrefAlignment == 0)
PointerPrefAlignment = PointerABIAlignment;
break;
case 'd':
DoubleABIAlignment = atoi(getToken(token,":").c_str()) / 8;
DoublePrefAlignment = atoi(getToken(token,":").c_str()) / 8;
if (DoublePrefAlignment == 0)
DoublePrefAlignment = DoubleABIAlignment;
break;
case 'f':
FloatABIAlignment = atoi(getToken(token, ":").c_str()) / 8;
FloatPrefAlignment = atoi(getToken(token,":").c_str()) / 8;
if (FloatPrefAlignment == 0)
FloatPrefAlignment = FloatABIAlignment;
break;
case 'l':
LongABIAlignment = atoi(getToken(token, ":").c_str()) / 8;
LongPrefAlignment = atoi(getToken(token,":").c_str()) / 8;
if (LongPrefAlignment == 0)
LongPrefAlignment = LongABIAlignment;
break;
case 'i':
IntABIAlignment = atoi(getToken(token, ":").c_str()) / 8;
IntPrefAlignment = atoi(getToken(token,":").c_str()) / 8;
if (IntPrefAlignment == 0)
IntPrefAlignment = IntABIAlignment;
break;
case 's':
ShortABIAlignment = atoi(getToken(token, ":").c_str()) / 8;
ShortPrefAlignment = atoi(getToken(token,":").c_str()) / 8;
if (ShortPrefAlignment == 0)
ShortPrefAlignment = ShortABIAlignment;
break;
case 'b':
ByteABIAlignment = atoi(getToken(token, ":").c_str()) / 8;
BytePrefAlignment = atoi(getToken(token,":").c_str()) / 8;
if (BytePrefAlignment == 0)
BytePrefAlignment = ByteABIAlignment;
break;
case 'B':
BoolABIAlignment = atoi(getToken(token, ":").c_str()) / 8;
BoolPrefAlignment = atoi(getToken(token,":").c_str()) / 8;
if (BoolPrefAlignment == 0)
BoolPrefAlignment = BoolABIAlignment;
break;
case 'A':
AggMinPrefAlignment = atoi(getToken(token,":").c_str()) / 8;
break;
default:
break;
}
}
// Unless explicitly specified, the alignments for longs and doubles is
// capped by pointer size.
if (LongABIAlignment == 0)
LongABIAlignment = LongPrefAlignment = PointerMemSize;
if (DoubleABIAlignment == 0)
DoubleABIAlignment = DoublePrefAlignment = PointerMemSize;
}
TargetData::TargetData(const Module *M) {
init(M->getDataLayout());
}
/// Layouts - The lazy cache of structure layout information maintained by
/// TargetData.
///
static std::map<std::pair<const TargetData*,const StructType*>,
StructLayout> *Layouts = 0;
TargetData::~TargetData() {
if (Layouts) {
// Remove any layouts for this TD.
std::map<std::pair<const TargetData*,
const StructType*>, StructLayout>::iterator
I = Layouts->lower_bound(std::make_pair(this, (const StructType*)0));
while (I != Layouts->end() && I->first.first == this)
Layouts->erase(I++);
if (Layouts->empty()) {
delete Layouts;
Layouts = 0;
}
}
}
std::string TargetData::getStringRepresentation() const {
std::stringstream repr;
if (LittleEndian)
repr << "e";
else
repr << "E";
repr << "-p:" << (PointerMemSize * 8) << ":" << (PointerABIAlignment * 8);
repr << "-d:" << (DoubleABIAlignment * 8) << ":"
<< (DoublePrefAlignment * 8);
repr << "-f:" << (FloatABIAlignment * 8) << ":"
<< (FloatPrefAlignment * 8);
repr << "-l:" << (LongABIAlignment * 8) << ":"
<< (LongPrefAlignment * 8);
repr << "-i:" << (IntABIAlignment * 8) << ":"
<< (IntPrefAlignment * 8);
repr << "-s:" << (ShortABIAlignment * 8) << ":"
<< (ShortPrefAlignment * 8);
repr << "-b:" << (ByteABIAlignment * 8) << ":"
<< (BytePrefAlignment * 8);
repr << "-B:" << (BoolABIAlignment * 8) << ":"
<< (BoolPrefAlignment * 8);
repr << "-A:" << (AggMinPrefAlignment * 8);
return repr.str();
}
const StructLayout *TargetData::getStructLayout(const StructType *Ty) const {
if (Layouts == 0)
Layouts = new std::map<std::pair<const TargetData*,const StructType*>,
StructLayout>();
std::map<std::pair<const TargetData*,const StructType*>,
StructLayout>::iterator
I = Layouts->lower_bound(std::make_pair(this, Ty));
if (I != Layouts->end() && I->first.first == this && I->first.second == Ty)
return &I->second;
else {
return &Layouts->insert(I, std::make_pair(std::make_pair(this, Ty),
StructLayout(Ty, *this)))->second;
}
}
/// InvalidateStructLayoutInfo - TargetData speculatively caches StructLayout
/// objects. If a TargetData object is alive when types are being refined and
/// removed, this method must be called whenever a StructType is removed to
/// avoid a dangling pointer in this cache.
void TargetData::InvalidateStructLayoutInfo(const StructType *Ty) const {
if (!Layouts) return; // No cache.
std::map<std::pair<const TargetData*,const StructType*>,
StructLayout>::iterator I = Layouts->find(std::make_pair(this, Ty));
if (I != Layouts->end())
Layouts->erase(I);
}
static inline void getTypeInfoABI(const Type *Ty, const TargetData *TD,
uint64_t &Size, unsigned char &Alignment) {
assert(Ty->isSized() && "Cannot getTypeInfo() on a type that is unsized!");
switch (Ty->getTypeID()) {
case Type::IntegerTyID: {
unsigned BitWidth = cast<IntegerType>(Ty)->getBitWidth();
if (BitWidth <= 8) {
Size = 1; Alignment = TD->getByteABIAlignment();
} else if (BitWidth <= 16) {
Size = 2; Alignment = TD->getShortABIAlignment();
} else if (BitWidth <= 32) {
Size = 4; Alignment = TD->getIntABIAlignment();
} else if (BitWidth <= 64) {
Size = 8; Alignment = TD->getLongABIAlignment();
} else {
Size = ((BitWidth + 7) / 8) & ~1;
Alignment = TD->getLongABIAlignment();
}
return;
}
case Type::VoidTyID: Size = 1; Alignment = TD->getByteABIAlignment(); return;
case Type::FloatTyID: Size = 4; Alignment = TD->getFloatABIAlignment(); return;
case Type::DoubleTyID: Size = 8; Alignment = TD->getDoubleABIAlignment(); return;
case Type::LabelTyID:
case Type::PointerTyID:
Size = TD->getPointerSize(); Alignment = TD->getPointerABIAlignment();
return;
case Type::ArrayTyID: {
const ArrayType *ATy = cast<ArrayType>(Ty);
getTypeInfoABI(ATy->getElementType(), TD, Size, Alignment);
unsigned AlignedSize = (Size + Alignment - 1)/Alignment*Alignment;
Size = AlignedSize*ATy->getNumElements();
return;
}
case Type::PackedTyID: {
const PackedType *PTy = cast<PackedType>(Ty);
getTypeInfoABI(PTy->getElementType(), TD, Size, Alignment);
unsigned AlignedSize = (Size + Alignment - 1)/Alignment*Alignment;
Size = AlignedSize*PTy->getNumElements();
// FIXME: The alignments of specific packed types are target dependent.
// For now, just set it to be equal to Size.
Alignment = Size;
return;
}
case Type::StructTyID: {
// Get the layout annotation... which is lazily created on demand.
const StructLayout *Layout = TD->getStructLayout(cast<StructType>(Ty));
Size = Layout->StructSize; Alignment = Layout->StructAlignment;
return;
}
default:
assert(0 && "Bad type for getTypeInfo!!!");
return;
}
}
static inline void getTypeInfoPref(const Type *Ty, const TargetData *TD,
uint64_t &Size, unsigned char &Alignment) {
assert(Ty->isSized() && "Cannot getTypeInfoPref() on a type that is unsized!");
switch (Ty->getTypeID()) {
case Type::IntegerTyID: {
unsigned BitWidth = cast<IntegerType>(Ty)->getBitWidth();
if (BitWidth <= 8) {
Size = 1; Alignment = TD->getBytePrefAlignment();
} else if (BitWidth <= 16) {
Size = 2; Alignment = TD->getShortPrefAlignment();
} else if (BitWidth <= 32) {
Size = 4; Alignment = TD->getIntPrefAlignment();
} else if (BitWidth <= 64) {
Size = 8; Alignment = TD->getLongPrefAlignment();
} else
assert(0 && "Integer types > 64 bits not supported.");
return;
}
case Type::VoidTyID:
Size = 1; Alignment = TD->getBytePrefAlignment();
return;
case Type::FloatTyID:
Size = 4; Alignment = TD->getFloatPrefAlignment();
return;
case Type::DoubleTyID:
Size = 8; Alignment = TD->getDoublePrefAlignment();
return;
case Type::LabelTyID:
case Type::PointerTyID:
Size = TD->getPointerSize(); Alignment = TD->getPointerPrefAlignment();
return;
case Type::ArrayTyID: {
const ArrayType *ATy = cast<ArrayType>(Ty);
getTypeInfoPref(ATy->getElementType(), TD, Size, Alignment);
unsigned AlignedSize = (Size + Alignment - 1)/Alignment*Alignment;
Size = AlignedSize*ATy->getNumElements();
return;
}
case Type::PackedTyID: {
const PackedType *PTy = cast<PackedType>(Ty);
getTypeInfoPref(PTy->getElementType(), TD, Size, Alignment);
unsigned AlignedSize = (Size + Alignment - 1)/Alignment*Alignment;
Size = AlignedSize*PTy->getNumElements();
// FIXME: The alignments of specific packed types are target dependent.
// For now, just set it to be equal to Size.
Alignment = Size;
return;
}
case Type::StructTyID: {
// Get the layout annotation... which is lazily created on demand;
// enforce minimum aggregate alignment.
const StructLayout *Layout = TD->getStructLayout(cast<StructType>(Ty));
Size = Layout->StructSize;
Alignment = std::max(Layout->StructAlignment,
(const unsigned int) TD->getAggMinPrefAlignment());
return;
}
default:
assert(0 && "Bad type for getTypeInfoPref!!!");
return;
}
}
uint64_t TargetData::getTypeSize(const Type *Ty) const {
uint64_t Size;
unsigned char Align;
getTypeInfoABI(Ty, this, Size, Align);
return Size;
}
uint64_t TargetData::getTypeSizeInBits(const Type *Ty) const {
if (Ty->isInteger())
return cast<IntegerType>(Ty)->getBitWidth();
uint64_t Size;
unsigned char Align;
getTypeInfoABI(Ty, this, Size, Align);
return Size * 8;
}
unsigned char TargetData::getTypeAlignmentABI(const Type *Ty) const {
uint64_t Size;
unsigned char Align;
getTypeInfoABI(Ty, this, Size, Align);
return Align;
}
unsigned char TargetData::getTypeAlignmentPref(const Type *Ty) const {
uint64_t Size;
unsigned char Align;
getTypeInfoPref(Ty, this, Size, Align);
return Align;
}
unsigned char TargetData::getPreferredTypeAlignmentShift(const Type *Ty) const {
unsigned Align = getTypeAlignmentPref(Ty);
assert(!(Align & (Align-1)) && "Alignment is not a power of two!");
return Log2_32(Align);
}
/// getIntPtrType - Return an unsigned integer type that is the same size or
/// greater to the host pointer size.
const Type *TargetData::getIntPtrType() const {
switch (getPointerSize()) {
default: assert(0 && "Unknown pointer size!");
case 2: return Type::Int16Ty;
case 4: return Type::Int32Ty;
case 8: return Type::Int64Ty;
}
}
uint64_t TargetData::getIndexedOffset(const Type *ptrTy,
const std::vector<Value*> &Idx) const {
const Type *Ty = ptrTy;
assert(isa<PointerType>(Ty) && "Illegal argument for getIndexedOffset()");
uint64_t Result = 0;
generic_gep_type_iterator<std::vector<Value*>::const_iterator>
TI = gep_type_begin(ptrTy, Idx.begin(), Idx.end());
for (unsigned CurIDX = 0; CurIDX != Idx.size(); ++CurIDX, ++TI) {
if (const StructType *STy = dyn_cast<StructType>(*TI)) {
assert(Idx[CurIDX]->getType() == Type::Int32Ty && "Illegal struct idx");
unsigned FieldNo = cast<ConstantInt>(Idx[CurIDX])->getZExtValue();
// Get structure layout information...
const StructLayout *Layout = getStructLayout(STy);
// Add in the offset, as calculated by the structure layout info...
assert(FieldNo < Layout->MemberOffsets.size() &&"FieldNo out of range!");
Result += Layout->MemberOffsets[FieldNo];
// Update Ty to refer to current element
Ty = STy->getElementType(FieldNo);
} else {
// Update Ty to refer to current element
Ty = cast<SequentialType>(Ty)->getElementType();
// Get the array index and the size of each array element.
int64_t arrayIdx = cast<ConstantInt>(Idx[CurIDX])->getSExtValue();
Result += arrayIdx * (int64_t)getTypeSize(Ty);
}
}
return Result;
}
/// getPreferredAlignmentLog - Return the preferred alignment of the
/// specified global, returned in log form. This includes an explicitly
/// requested alignment (if the global has one).
unsigned TargetData::getPreferredAlignmentLog(const GlobalVariable *GV) const {
const Type *ElemType = GV->getType()->getElementType();
unsigned Alignment = getPreferredTypeAlignmentShift(ElemType);
if (GV->getAlignment() > (1U << Alignment))
Alignment = Log2_32(GV->getAlignment());
if (GV->hasInitializer()) {
if (Alignment < 4) {
// If the global is not external, see if it is large. If so, give it a
// larger alignment.
if (getTypeSize(ElemType) > 128)
Alignment = 4; // 16-byte alignment.
}
}
return Alignment;
}
Reference in New Issue View Git Blame Copy Permalink