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-rw-r--r--lib/Target/TargetData.cpp281
1 files changed, 281 insertions, 0 deletions
diff --git a/lib/Target/TargetData.cpp b/lib/Target/TargetData.cpp
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+//===-- 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 <algorithm>
+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 getTypeInfo(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;
+ getTypeInfo(Ty, &TD, TySize, A);
+ TyAlign = 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
+//===----------------------------------------------------------------------===//
+
+TargetData::TargetData(const std::string &TargetName,
+ bool isLittleEndian, unsigned char PtrSize,
+ unsigned char PtrAl, unsigned char DoubleAl,
+ unsigned char FloatAl, unsigned char LongAl,
+ unsigned char IntAl, unsigned char ShortAl,
+ unsigned char ByteAl, unsigned char BoolAl) {
+
+ // If this assert triggers, a pass "required" TargetData information, but the
+ // top level tool did not provide one for it. We do not want to default
+ // construct, or else we might end up using a bad endianness or pointer size!
+ //
+ assert(!TargetName.empty() &&
+ "ERROR: Tool did not specify a target data to use!");
+
+ LittleEndian = isLittleEndian;
+ PointerSize = PtrSize;
+ PointerAlignment = PtrAl;
+ DoubleAlignment = DoubleAl;
+ FloatAlignment = FloatAl;
+ LongAlignment = LongAl;
+ IntAlignment = IntAl;
+ ShortAlignment = ShortAl;
+ ByteAlignment = ByteAl;
+ BoolAlignment = BoolAl;
+}
+
+TargetData::TargetData(const std::string &ToolName, const Module *M) {
+ LittleEndian = M->getEndianness() != Module::BigEndian;
+ PointerSize = M->getPointerSize() != Module::Pointer64 ? 4 : 8;
+ PointerAlignment = PointerSize;
+ DoubleAlignment = PointerSize;
+ FloatAlignment = 4;
+ LongAlignment = PointerSize;
+ IntAlignment = 4;
+ ShortAlignment = 2;
+ ByteAlignment = 1;
+ BoolAlignment = 1;
+}
+
+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;
+ }
+ }
+}
+
+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;
+ }
+}
+
+static inline void getTypeInfo(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::BoolTyID: Size = 1; Alignment = TD->getBoolAlignment(); return;
+ case Type::VoidTyID:
+ case Type::UByteTyID:
+ case Type::SByteTyID: Size = 1; Alignment = TD->getByteAlignment(); return;
+ case Type::UShortTyID:
+ case Type::ShortTyID: Size = 2; Alignment = TD->getShortAlignment(); return;
+ case Type::UIntTyID:
+ case Type::IntTyID: Size = 4; Alignment = TD->getIntAlignment(); return;
+ case Type::ULongTyID:
+ case Type::LongTyID: Size = 8; Alignment = TD->getLongAlignment(); return;
+ case Type::FloatTyID: Size = 4; Alignment = TD->getFloatAlignment(); return;
+ case Type::DoubleTyID: Size = 8; Alignment = TD->getDoubleAlignment(); return;
+ case Type::LabelTyID:
+ case Type::PointerTyID:
+ Size = TD->getPointerSize(); Alignment = TD->getPointerAlignment();
+ return;
+ case Type::ArrayTyID: {
+ const ArrayType *ATy = cast<ArrayType>(Ty);
+ getTypeInfo(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);
+ getTypeInfo(PTy->getElementType(), TD, Size, Alignment);
+ unsigned AlignedSize = (Size + Alignment - 1)/Alignment*Alignment;
+ Size = AlignedSize*PTy->getNumElements();
+ 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;
+ }
+}
+
+uint64_t TargetData::getTypeSize(const Type *Ty) const {
+ uint64_t Size;
+ unsigned char Align;
+ getTypeInfo(Ty, this, Size, Align);
+ return Size;
+}
+
+unsigned char TargetData::getTypeAlignment(const Type *Ty) const {
+ uint64_t Size;
+ unsigned char Align;
+ getTypeInfo(Ty, this, Size, Align);
+ return Align;
+}
+
+unsigned char TargetData::getTypeAlignmentShift(const Type *Ty) const {
+ unsigned Align = getTypeAlignment(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::UShortTy;
+ case 4: return Type::UIntTy;
+ case 8: return Type::ULongTy;
+ }
+}
+
+
+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::UIntTy && "Illegal struct idx");
+ unsigned FieldNo = cast<ConstantUInt>(Idx[CurIDX])->getValue();
+
+ // 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])->getRawValue();
+ Result += arrayIdx * (int64_t)getTypeSize(Ty);
+ }
+ }
+
+ return Result;
+}
+
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