1 //===-- TargetData.cpp - Data size & alignment routines --------------------==//
3 // The LLVM Compiler Infrastructure
5 // This file was developed by the LLVM research group and is distributed under
6 // the University of Illinois Open Source License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file defines target properties related to datatype size/offset/alignment
13 // This structure should be created once, filled in if the defaults are not
14 // correct and then passed around by const&. None of the members functions
15 // require modification to the object.
17 //===----------------------------------------------------------------------===//
19 #include "llvm/Target/TargetData.h"
20 #include "llvm/Module.h"
21 #include "llvm/DerivedTypes.h"
22 #include "llvm/Constants.h"
23 #include "llvm/Support/GetElementPtrTypeIterator.h"
24 #include "llvm/Support/MathExtras.h"
25 #include "llvm/ADT/StringExtras.h"
31 // Handle the Pass registration stuff necessary to use TargetData's.
33 // Register the default SparcV9 implementation...
34 RegisterPass<TargetData> X("targetdata", "Target Data Layout");
37 static inline void getTypeInfo(const Type *Ty, const TargetData *TD,
38 uint64_t &Size, unsigned char &Alignment);
40 //===----------------------------------------------------------------------===//
41 // Support for StructLayout
42 //===----------------------------------------------------------------------===//
44 StructLayout::StructLayout(const StructType *ST, const TargetData &TD) {
48 // Loop over each of the elements, placing them in memory...
49 for (StructType::element_iterator TI = ST->element_begin(),
50 TE = ST->element_end(); TI != TE; ++TI) {
55 getTypeInfo(Ty, &TD, TySize, A);
58 // Add padding if necessary to make the data element aligned properly...
59 if (StructSize % TyAlign != 0)
60 StructSize = (StructSize/TyAlign + 1) * TyAlign; // Add padding...
62 // Keep track of maximum alignment constraint
63 StructAlignment = std::max(TyAlign, StructAlignment);
65 MemberOffsets.push_back(StructSize);
66 StructSize += TySize; // Consume space for this data item
69 // Empty structures have alignment of 1 byte.
70 if (StructAlignment == 0) StructAlignment = 1;
72 // Add padding to the end of the struct so that it could be put in an array
73 // and all array elements would be aligned correctly.
74 if (StructSize % StructAlignment != 0)
75 StructSize = (StructSize/StructAlignment + 1) * StructAlignment;
79 /// getElementContainingOffset - Given a valid offset into the structure,
80 /// return the structure index that contains it.
81 unsigned StructLayout::getElementContainingOffset(uint64_t Offset) const {
82 std::vector<uint64_t>::const_iterator SI =
83 std::upper_bound(MemberOffsets.begin(), MemberOffsets.end(),
85 assert(SI != MemberOffsets.begin() && "Offset not in structure type!");
87 assert(*SI <= Offset && "upper_bound didn't work");
88 assert((SI == MemberOffsets.begin() || *(SI-1) < Offset) &&
89 (SI+1 == MemberOffsets.end() || *(SI+1) > Offset) &&
90 "Upper bound didn't work!");
91 return SI-MemberOffsets.begin();
94 //===----------------------------------------------------------------------===//
95 // TargetData Class Implementation
96 //===----------------------------------------------------------------------===//
98 TargetData::TargetData(const std::string &TargetName,
99 bool isLittleEndian, unsigned char PtrSize,
100 unsigned char PtrAl, unsigned char DoubleAl,
101 unsigned char FloatAl, unsigned char LongAl,
102 unsigned char IntAl, unsigned char ShortAl,
103 unsigned char ByteAl, unsigned char BoolAl) {
105 // If this assert triggers, a pass "required" TargetData information, but the
106 // top level tool did not provide one for it. We do not want to default
107 // construct, or else we might end up using a bad endianness or pointer size!
109 assert(!TargetName.empty() &&
110 "ERROR: Tool did not specify a target data to use!");
112 LittleEndian = isLittleEndian;
113 PointerSize = PtrSize;
114 PointerAlignment = PtrAl;
115 DoubleAlignment = DoubleAl;
116 FloatAlignment = FloatAl;
117 LongAlignment = LongAl;
118 IntAlignment = IntAl;
119 ShortAlignment = ShortAl;
120 ByteAlignment = ByteAl;
121 BoolAlignment = BoolAl;
124 TargetData::TargetData(const std::string &TargetName,
125 const std::string &TargetDescription) {
126 assert(!TargetName.empty() &&
127 "ERROR: Tool did not specify a target data to use!");
130 std::string temp = TargetDescription;
132 LittleEndian = false;
134 PointerAlignment = 8;
143 while (!temp.empty()) {
144 std::string token = getToken(temp, "-");
146 char signal = getToken(token, ":")[0];
150 LittleEndian = false;
156 PointerSize = atoi(getToken(token,":").c_str()) / 8;
157 PointerAlignment = atoi(getToken(token,":").c_str()) / 8;
160 DoubleAlignment = atoi(getToken(token,":").c_str()) / 8;
163 FloatAlignment = atoi(getToken(token, ":").c_str()) / 8;
166 LongAlignment = atoi(getToken(token, ":").c_str()) / 8;
169 IntAlignment = atoi(getToken(token, ":").c_str()) / 8;
172 ShortAlignment = atoi(getToken(token, ":").c_str()) / 8;
175 ByteAlignment = atoi(getToken(token, ":").c_str()) / 8;
178 BoolAlignment = atoi(getToken(token, ":").c_str()) / 8;
186 TargetData::TargetData(const std::string &ToolName, const Module *M) {
187 LittleEndian = M->getEndianness() != Module::BigEndian;
188 PointerSize = M->getPointerSize() != Module::Pointer64 ? 4 : 8;
189 PointerAlignment = PointerSize;
190 DoubleAlignment = PointerSize;
192 LongAlignment = PointerSize;
199 /// Layouts - The lazy cache of structure layout information maintained by
202 static std::map<std::pair<const TargetData*,const StructType*>,
203 StructLayout> *Layouts = 0;
206 TargetData::~TargetData() {
208 // Remove any layouts for this TD.
209 std::map<std::pair<const TargetData*,
210 const StructType*>, StructLayout>::iterator
211 I = Layouts->lower_bound(std::make_pair(this, (const StructType*)0));
212 while (I != Layouts->end() && I->first.first == this)
214 if (Layouts->empty()) {
221 std::string TargetData::getStringRepresentation() const {
222 std::stringstream repr;
229 repr << "-p:" << (PointerSize * 8) << ":" << (PointerAlignment * 8);
230 repr << "-d:64:" << (DoubleAlignment * 8);
231 repr << "-f:32:" << (FloatAlignment * 8);
232 repr << "-l:64:" << (LongAlignment * 8);
233 repr << "-i:32:" << (IntAlignment * 8);
234 repr << "-s:16:" << (ShortAlignment * 8);
235 repr << "-b:8:" << (ByteAlignment * 8);
236 repr << "-B:8:" << (BoolAlignment * 8);
241 const StructLayout *TargetData::getStructLayout(const StructType *Ty) const {
243 Layouts = new std::map<std::pair<const TargetData*,const StructType*>,
245 std::map<std::pair<const TargetData*,const StructType*>,
246 StructLayout>::iterator
247 I = Layouts->lower_bound(std::make_pair(this, Ty));
248 if (I != Layouts->end() && I->first.first == this && I->first.second == Ty)
251 return &Layouts->insert(I, std::make_pair(std::make_pair(this, Ty),
252 StructLayout(Ty, *this)))->second;
256 /// InvalidateStructLayoutInfo - TargetData speculatively caches StructLayout
257 /// objects. If a TargetData object is alive when types are being refined and
258 /// removed, this method must be called whenever a StructType is removed to
259 /// avoid a dangling pointer in this cache.
260 void TargetData::InvalidateStructLayoutInfo(const StructType *Ty) const {
261 if (!Layouts) return; // No cache.
263 std::map<std::pair<const TargetData*,const StructType*>,
264 StructLayout>::iterator I = Layouts->find(std::make_pair(this, Ty));
265 if (I != Layouts->end())
271 static inline void getTypeInfo(const Type *Ty, const TargetData *TD,
272 uint64_t &Size, unsigned char &Alignment) {
273 assert(Ty->isSized() && "Cannot getTypeInfo() on a type that is unsized!");
274 switch (Ty->getTypeID()) {
275 case Type::BoolTyID: Size = 1; Alignment = TD->getBoolAlignment(); return;
277 case Type::UByteTyID:
278 case Type::SByteTyID: Size = 1; Alignment = TD->getByteAlignment(); return;
279 case Type::UShortTyID:
280 case Type::ShortTyID: Size = 2; Alignment = TD->getShortAlignment(); return;
282 case Type::IntTyID: Size = 4; Alignment = TD->getIntAlignment(); return;
283 case Type::ULongTyID:
284 case Type::LongTyID: Size = 8; Alignment = TD->getLongAlignment(); return;
285 case Type::FloatTyID: Size = 4; Alignment = TD->getFloatAlignment(); return;
286 case Type::DoubleTyID: Size = 8; Alignment = TD->getDoubleAlignment(); return;
287 case Type::LabelTyID:
288 case Type::PointerTyID:
289 Size = TD->getPointerSize(); Alignment = TD->getPointerAlignment();
291 case Type::ArrayTyID: {
292 const ArrayType *ATy = cast<ArrayType>(Ty);
293 getTypeInfo(ATy->getElementType(), TD, Size, Alignment);
294 unsigned AlignedSize = (Size + Alignment - 1)/Alignment*Alignment;
295 Size = AlignedSize*ATy->getNumElements();
298 case Type::PackedTyID: {
299 const PackedType *PTy = cast<PackedType>(Ty);
300 getTypeInfo(PTy->getElementType(), TD, Size, Alignment);
301 unsigned AlignedSize = (Size + Alignment - 1)/Alignment*Alignment;
302 Size = AlignedSize*PTy->getNumElements();
303 // FIXME: The alignments of specific packed types are target dependent.
304 // For now, just set it to be equal to Size.
308 case Type::StructTyID: {
309 // Get the layout annotation... which is lazily created on demand.
310 const StructLayout *Layout = TD->getStructLayout(cast<StructType>(Ty));
311 Size = Layout->StructSize; Alignment = Layout->StructAlignment;
316 assert(0 && "Bad type for getTypeInfo!!!");
321 uint64_t TargetData::getTypeSize(const Type *Ty) const {
324 getTypeInfo(Ty, this, Size, Align);
328 unsigned char TargetData::getTypeAlignment(const Type *Ty) const {
331 getTypeInfo(Ty, this, Size, Align);
335 unsigned char TargetData::getTypeAlignmentShift(const Type *Ty) const {
336 unsigned Align = getTypeAlignment(Ty);
337 assert(!(Align & (Align-1)) && "Alignment is not a power of two!");
338 return Log2_32(Align);
341 /// getIntPtrType - Return an unsigned integer type that is the same size or
342 /// greater to the host pointer size.
343 const Type *TargetData::getIntPtrType() const {
344 switch (getPointerSize()) {
345 default: assert(0 && "Unknown pointer size!");
346 case 2: return Type::UShortTy;
347 case 4: return Type::UIntTy;
348 case 8: return Type::ULongTy;
353 uint64_t TargetData::getIndexedOffset(const Type *ptrTy,
354 const std::vector<Value*> &Idx) const {
355 const Type *Ty = ptrTy;
356 assert(isa<PointerType>(Ty) && "Illegal argument for getIndexedOffset()");
359 generic_gep_type_iterator<std::vector<Value*>::const_iterator>
360 TI = gep_type_begin(ptrTy, Idx.begin(), Idx.end());
361 for (unsigned CurIDX = 0; CurIDX != Idx.size(); ++CurIDX, ++TI) {
362 if (const StructType *STy = dyn_cast<StructType>(*TI)) {
363 assert(Idx[CurIDX]->getType() == Type::UIntTy && "Illegal struct idx");
364 unsigned FieldNo = cast<ConstantUInt>(Idx[CurIDX])->getValue();
366 // Get structure layout information...
367 const StructLayout *Layout = getStructLayout(STy);
369 // Add in the offset, as calculated by the structure layout info...
370 assert(FieldNo < Layout->MemberOffsets.size() &&"FieldNo out of range!");
371 Result += Layout->MemberOffsets[FieldNo];
373 // Update Ty to refer to current element
374 Ty = STy->getElementType(FieldNo);
376 // Update Ty to refer to current element
377 Ty = cast<SequentialType>(Ty)->getElementType();
379 // Get the array index and the size of each array element.
380 int64_t arrayIdx = cast<ConstantInt>(Idx[CurIDX])->getRawValue();
381 Result += arrayIdx * (int64_t)getTypeSize(Ty);