1 //===- BitcodeReader.cpp - Internal BitcodeReader implementation ----------===//
3 // The LLVM Compiler Infrastructure
5 // This file was developed by Chris Lattner and is distributed under
6 // the University of Illinois Open Source License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This header defines the BitcodeReader class.
12 //===----------------------------------------------------------------------===//
14 #include "BitcodeReader.h"
15 #include "llvm/Bitcode/BitstreamReader.h"
16 #include "llvm/Constants.h"
17 #include "llvm/DerivedTypes.h"
18 #include "llvm/Module.h"
19 #include "llvm/ADT/SmallString.h"
20 #include "llvm/Support/MathExtras.h"
23 /// ConvertToString - Convert a string from a record into an std::string, return
25 template<typename StrTy>
26 static bool ConvertToString(SmallVector<uint64_t, 64> &Record, unsigned Idx,
28 if (Record.size() < Idx+1 || Record.size() < Record[Idx]+Idx+1)
31 for (unsigned i = 0, e = Record[Idx]; i != e; ++i)
32 Result += (char)Record[Idx+i+1];
36 static GlobalValue::LinkageTypes GetDecodedLinkage(unsigned Val) {
38 default: // Map unknown/new linkages to external
39 case 0: return GlobalValue::ExternalLinkage;
40 case 1: return GlobalValue::WeakLinkage;
41 case 2: return GlobalValue::AppendingLinkage;
42 case 3: return GlobalValue::InternalLinkage;
43 case 4: return GlobalValue::LinkOnceLinkage;
44 case 5: return GlobalValue::DLLImportLinkage;
45 case 6: return GlobalValue::DLLExportLinkage;
46 case 7: return GlobalValue::ExternalWeakLinkage;
50 static GlobalValue::VisibilityTypes GetDecodedVisibility(unsigned Val) {
52 default: // Map unknown visibilities to default.
53 case 0: return GlobalValue::DefaultVisibility;
54 case 1: return GlobalValue::HiddenVisibility;
58 static int GetDecodedCastOpcode(unsigned Val) {
61 case bitc::CAST_TRUNC : return Instruction::Trunc;
62 case bitc::CAST_ZEXT : return Instruction::ZExt;
63 case bitc::CAST_SEXT : return Instruction::SExt;
64 case bitc::CAST_FPTOUI : return Instruction::FPToUI;
65 case bitc::CAST_FPTOSI : return Instruction::FPToSI;
66 case bitc::CAST_UITOFP : return Instruction::UIToFP;
67 case bitc::CAST_SITOFP : return Instruction::SIToFP;
68 case bitc::CAST_FPTRUNC : return Instruction::FPTrunc;
69 case bitc::CAST_FPEXT : return Instruction::FPExt;
70 case bitc::CAST_PTRTOINT: return Instruction::PtrToInt;
71 case bitc::CAST_INTTOPTR: return Instruction::IntToPtr;
72 case bitc::CAST_BITCAST : return Instruction::BitCast;
75 static int GetDecodedBinaryOpcode(unsigned Val, const Type *Ty) {
78 case bitc::BINOP_ADD: return Instruction::Add;
79 case bitc::BINOP_SUB: return Instruction::Sub;
80 case bitc::BINOP_MUL: return Instruction::Mul;
81 case bitc::BINOP_UDIV: return Instruction::UDiv;
82 case bitc::BINOP_SDIV:
83 return Ty->isFPOrFPVector() ? Instruction::FDiv : Instruction::SDiv;
84 case bitc::BINOP_UREM: return Instruction::URem;
85 case bitc::BINOP_SREM:
86 return Ty->isFPOrFPVector() ? Instruction::FRem : Instruction::SRem;
87 case bitc::BINOP_SHL: return Instruction::Shl;
88 case bitc::BINOP_LSHR: return Instruction::LShr;
89 case bitc::BINOP_ASHR: return Instruction::AShr;
90 case bitc::BINOP_AND: return Instruction::And;
91 case bitc::BINOP_OR: return Instruction::Or;
92 case bitc::BINOP_XOR: return Instruction::Xor;
98 /// @brief A class for maintaining the slot number definition
99 /// as a placeholder for the actual definition for forward constants defs.
100 class ConstantPlaceHolder : public ConstantExpr {
101 ConstantPlaceHolder(); // DO NOT IMPLEMENT
102 void operator=(const ConstantPlaceHolder &); // DO NOT IMPLEMENT
105 ConstantPlaceHolder(const Type *Ty)
106 : ConstantExpr(Ty, Instruction::UserOp1, &Op, 1),
107 Op(UndefValue::get(Type::Int32Ty), this) {
112 Constant *BitcodeReaderValueList::getConstantFwdRef(unsigned Idx,
115 // Insert a bunch of null values.
117 OperandList = &Uses[0];
122 assert(Ty == getOperand(Idx)->getType() &&
123 "Type mismatch in constant table!");
124 return cast<Constant>(getOperand(Idx));
127 // Create and return a placeholder, which will later be RAUW'd.
128 Constant *C = new ConstantPlaceHolder(Ty);
129 Uses[Idx].init(C, this);
134 const Type *BitcodeReader::getTypeByID(unsigned ID, bool isTypeTable) {
135 // If the TypeID is in range, return it.
136 if (ID < TypeList.size())
137 return TypeList[ID].get();
138 if (!isTypeTable) return 0;
140 // The type table allows forward references. Push as many Opaque types as
141 // needed to get up to ID.
142 while (TypeList.size() <= ID)
143 TypeList.push_back(OpaqueType::get());
144 return TypeList.back().get();
148 bool BitcodeReader::ParseTypeTable(BitstreamReader &Stream) {
149 if (Stream.EnterSubBlock())
150 return Error("Malformed block record");
152 if (!TypeList.empty())
153 return Error("Multiple TYPE_BLOCKs found!");
155 SmallVector<uint64_t, 64> Record;
156 unsigned NumRecords = 0;
158 // Read all the records for this type table.
160 unsigned Code = Stream.ReadCode();
161 if (Code == bitc::END_BLOCK) {
162 if (NumRecords != TypeList.size())
163 return Error("Invalid type forward reference in TYPE_BLOCK");
164 if (Stream.ReadBlockEnd())
165 return Error("Error at end of type table block");
169 if (Code == bitc::ENTER_SUBBLOCK) {
170 // No known subblocks, always skip them.
171 Stream.ReadSubBlockID();
172 if (Stream.SkipBlock())
173 return Error("Malformed block record");
177 if (Code == bitc::DEFINE_ABBREV) {
178 Stream.ReadAbbrevRecord();
184 const Type *ResultTy = 0;
185 switch (Stream.ReadRecord(Code, Record)) {
186 default: // Default behavior: unknown type.
189 case bitc::TYPE_CODE_NUMENTRY: // TYPE_CODE_NUMENTRY: [numentries]
190 // TYPE_CODE_NUMENTRY contains a count of the number of types in the
191 // type list. This allows us to reserve space.
192 if (Record.size() < 1)
193 return Error("Invalid TYPE_CODE_NUMENTRY record");
194 TypeList.reserve(Record[0]);
196 case bitc::TYPE_CODE_META: // TYPE_CODE_META: [metacode]...
197 // No metadata supported yet.
198 if (Record.size() < 1)
199 return Error("Invalid TYPE_CODE_META record");
202 case bitc::TYPE_CODE_VOID: // VOID
203 ResultTy = Type::VoidTy;
205 case bitc::TYPE_CODE_FLOAT: // FLOAT
206 ResultTy = Type::FloatTy;
208 case bitc::TYPE_CODE_DOUBLE: // DOUBLE
209 ResultTy = Type::DoubleTy;
211 case bitc::TYPE_CODE_LABEL: // LABEL
212 ResultTy = Type::LabelTy;
214 case bitc::TYPE_CODE_OPAQUE: // OPAQUE
217 case bitc::TYPE_CODE_INTEGER: // INTEGER: [width]
218 if (Record.size() < 1)
219 return Error("Invalid Integer type record");
221 ResultTy = IntegerType::get(Record[0]);
223 case bitc::TYPE_CODE_POINTER: // POINTER: [pointee type]
224 if (Record.size() < 1)
225 return Error("Invalid POINTER type record");
226 ResultTy = PointerType::get(getTypeByID(Record[0], true));
228 case bitc::TYPE_CODE_FUNCTION: {
229 // FUNCTION: [vararg, retty, #pararms, paramty N]
230 if (Record.size() < 3 || Record.size() < Record[2]+3)
231 return Error("Invalid FUNCTION type record");
232 std::vector<const Type*> ArgTys;
233 for (unsigned i = 0, e = Record[2]; i != e; ++i)
234 ArgTys.push_back(getTypeByID(Record[3+i], true));
237 ResultTy = FunctionType::get(getTypeByID(Record[1], true), ArgTys,
241 case bitc::TYPE_CODE_STRUCT: { // STRUCT: [ispacked, #elts, eltty x N]
242 if (Record.size() < 2 || Record.size() < Record[1]+2)
243 return Error("Invalid STRUCT type record");
244 std::vector<const Type*> EltTys;
245 for (unsigned i = 0, e = Record[1]; i != e; ++i)
246 EltTys.push_back(getTypeByID(Record[2+i], true));
247 ResultTy = StructType::get(EltTys, Record[0]);
250 case bitc::TYPE_CODE_ARRAY: // ARRAY: [numelts, eltty]
251 if (Record.size() < 2)
252 return Error("Invalid ARRAY type record");
253 ResultTy = ArrayType::get(getTypeByID(Record[1], true), Record[0]);
255 case bitc::TYPE_CODE_VECTOR: // VECTOR: [numelts, eltty]
256 if (Record.size() < 2)
257 return Error("Invalid VECTOR type record");
258 ResultTy = VectorType::get(getTypeByID(Record[1], true), Record[0]);
262 if (NumRecords == TypeList.size()) {
263 // If this is a new type slot, just append it.
264 TypeList.push_back(ResultTy ? ResultTy : OpaqueType::get());
266 } else if (ResultTy == 0) {
267 // Otherwise, this was forward referenced, so an opaque type was created,
268 // but the result type is actually just an opaque. Leave the one we
269 // created previously.
272 // Otherwise, this was forward referenced, so an opaque type was created.
273 // Resolve the opaque type to the real type now.
274 assert(NumRecords < TypeList.size() && "Typelist imbalance");
275 const OpaqueType *OldTy = cast<OpaqueType>(TypeList[NumRecords++].get());
277 // Don't directly push the new type on the Tab. Instead we want to replace
278 // the opaque type we previously inserted with the new concrete value. The
279 // refinement from the abstract (opaque) type to the new type causes all
280 // uses of the abstract type to use the concrete type (NewTy). This will
281 // also cause the opaque type to be deleted.
282 const_cast<OpaqueType*>(OldTy)->refineAbstractTypeTo(ResultTy);
284 // This should have replaced the old opaque type with the new type in the
285 // value table... or with a preexisting type that was already in the
286 // system. Let's just make sure it did.
287 assert(TypeList[NumRecords-1].get() != OldTy &&
288 "refineAbstractType didn't work!");
294 bool BitcodeReader::ParseTypeSymbolTable(BitstreamReader &Stream) {
295 if (Stream.EnterSubBlock())
296 return Error("Malformed block record");
298 SmallVector<uint64_t, 64> Record;
300 // Read all the records for this type table.
301 std::string TypeName;
303 unsigned Code = Stream.ReadCode();
304 if (Code == bitc::END_BLOCK) {
305 if (Stream.ReadBlockEnd())
306 return Error("Error at end of type symbol table block");
310 if (Code == bitc::ENTER_SUBBLOCK) {
311 // No known subblocks, always skip them.
312 Stream.ReadSubBlockID();
313 if (Stream.SkipBlock())
314 return Error("Malformed block record");
318 if (Code == bitc::DEFINE_ABBREV) {
319 Stream.ReadAbbrevRecord();
325 switch (Stream.ReadRecord(Code, Record)) {
326 default: // Default behavior: unknown type.
328 case bitc::TST_CODE_ENTRY: // TST_ENTRY: [typeid, namelen, namechar x N]
329 if (ConvertToString(Record, 1, TypeName))
330 return Error("Invalid TST_ENTRY record");
331 unsigned TypeID = Record[0];
332 if (TypeID >= TypeList.size())
333 return Error("Invalid Type ID in TST_ENTRY record");
335 TheModule->addTypeName(TypeName, TypeList[TypeID].get());
342 bool BitcodeReader::ParseValueSymbolTable(BitstreamReader &Stream) {
343 if (Stream.EnterSubBlock())
344 return Error("Malformed block record");
346 SmallVector<uint64_t, 64> Record;
348 // Read all the records for this value table.
349 SmallString<128> ValueName;
351 unsigned Code = Stream.ReadCode();
352 if (Code == bitc::END_BLOCK) {
353 if (Stream.ReadBlockEnd())
354 return Error("Error at end of value symbol table block");
357 if (Code == bitc::ENTER_SUBBLOCK) {
358 // No known subblocks, always skip them.
359 Stream.ReadSubBlockID();
360 if (Stream.SkipBlock())
361 return Error("Malformed block record");
365 if (Code == bitc::DEFINE_ABBREV) {
366 Stream.ReadAbbrevRecord();
372 switch (Stream.ReadRecord(Code, Record)) {
373 default: // Default behavior: unknown type.
375 case bitc::TST_CODE_ENTRY: // VST_ENTRY: [valueid, namelen, namechar x N]
376 if (ConvertToString(Record, 1, ValueName))
377 return Error("Invalid TST_ENTRY record");
378 unsigned ValueID = Record[0];
379 if (ValueID >= ValueList.size())
380 return Error("Invalid Value ID in VST_ENTRY record");
381 Value *V = ValueList[ValueID];
383 V->setName(&ValueName[0], ValueName.size());
390 /// DecodeSignRotatedValue - Decode a signed value stored with the sign bit in
391 /// the LSB for dense VBR encoding.
392 static uint64_t DecodeSignRotatedValue(uint64_t V) {
397 // There is no such thing as -0 with integers. "-0" really means MININT.
401 /// ResolveGlobalAndAliasInits - Resolve all of the initializers for global
402 /// values and aliases that we can.
403 bool BitcodeReader::ResolveGlobalAndAliasInits() {
404 std::vector<std::pair<GlobalVariable*, unsigned> > GlobalInitWorklist;
405 std::vector<std::pair<GlobalAlias*, unsigned> > AliasInitWorklist;
407 GlobalInitWorklist.swap(GlobalInits);
408 AliasInitWorklist.swap(AliasInits);
410 while (!GlobalInitWorklist.empty()) {
411 unsigned ValID = GlobalInitWorklist.back().second;
412 if (ValID >= ValueList.size()) {
413 // Not ready to resolve this yet, it requires something later in the file.
414 GlobalInits.push_back(GlobalInitWorklist.back());
416 if (Constant *C = dyn_cast<Constant>(ValueList[ValID]))
417 GlobalInitWorklist.back().first->setInitializer(C);
419 return Error("Global variable initializer is not a constant!");
421 GlobalInitWorklist.pop_back();
424 while (!AliasInitWorklist.empty()) {
425 unsigned ValID = AliasInitWorklist.back().second;
426 if (ValID >= ValueList.size()) {
427 AliasInits.push_back(AliasInitWorklist.back());
429 if (Constant *C = dyn_cast<Constant>(ValueList[ValID]))
430 AliasInitWorklist.back().first->setAliasee(
432 cast<GlobalValue>(C));
434 return Error("Alias initializer is not a constant!");
436 AliasInitWorklist.pop_back();
442 bool BitcodeReader::ParseConstants(BitstreamReader &Stream) {
443 if (Stream.EnterSubBlock())
444 return Error("Malformed block record");
446 SmallVector<uint64_t, 64> Record;
448 // Read all the records for this value table.
449 const Type *CurTy = Type::Int32Ty;
450 unsigned NextCstNo = ValueList.size();
452 unsigned Code = Stream.ReadCode();
453 if (Code == bitc::END_BLOCK) {
454 if (NextCstNo != ValueList.size())
455 return Error("Invalid constant reference!");
457 if (Stream.ReadBlockEnd())
458 return Error("Error at end of constants block");
462 if (Code == bitc::ENTER_SUBBLOCK) {
463 // No known subblocks, always skip them.
464 Stream.ReadSubBlockID();
465 if (Stream.SkipBlock())
466 return Error("Malformed block record");
470 if (Code == bitc::DEFINE_ABBREV) {
471 Stream.ReadAbbrevRecord();
478 switch (Stream.ReadRecord(Code, Record)) {
479 default: // Default behavior: unknown constant
480 case bitc::CST_CODE_UNDEF: // UNDEF
481 V = UndefValue::get(CurTy);
483 case bitc::CST_CODE_SETTYPE: // SETTYPE: [typeid]
485 return Error("Malformed CST_SETTYPE record");
486 if (Record[0] >= TypeList.size())
487 return Error("Invalid Type ID in CST_SETTYPE record");
488 CurTy = TypeList[Record[0]];
489 continue; // Skip the ValueList manipulation.
490 case bitc::CST_CODE_NULL: // NULL
491 V = Constant::getNullValue(CurTy);
493 case bitc::CST_CODE_INTEGER: // INTEGER: [intval]
494 if (!isa<IntegerType>(CurTy) || Record.empty())
495 return Error("Invalid CST_INTEGER record");
496 V = ConstantInt::get(CurTy, DecodeSignRotatedValue(Record[0]));
498 case bitc::CST_CODE_WIDE_INTEGER: {// WIDE_INTEGER: [n, n x intval]
499 if (!isa<IntegerType>(CurTy) || Record.empty() ||
500 Record.size() < Record[0]+1)
501 return Error("Invalid WIDE_INTEGER record");
503 unsigned NumWords = Record[0];
504 SmallVector<uint64_t, 8> Words;
505 Words.resize(NumWords);
506 for (unsigned i = 0; i != NumWords; ++i)
507 Words[i] = DecodeSignRotatedValue(Record[i+1]);
508 V = ConstantInt::get(APInt(cast<IntegerType>(CurTy)->getBitWidth(),
509 NumWords, &Words[0]));
512 case bitc::CST_CODE_FLOAT: // FLOAT: [fpval]
514 return Error("Invalid FLOAT record");
515 if (CurTy == Type::FloatTy)
516 V = ConstantFP::get(CurTy, BitsToFloat(Record[0]));
517 else if (CurTy == Type::DoubleTy)
518 V = ConstantFP::get(CurTy, BitsToDouble(Record[0]));
520 V = UndefValue::get(CurTy);
523 case bitc::CST_CODE_AGGREGATE: {// AGGREGATE: [n, n x value number]
524 if (Record.empty() || Record.size() < Record[0]+1)
525 return Error("Invalid CST_AGGREGATE record");
527 unsigned Size = Record[0];
528 std::vector<Constant*> Elts;
530 if (const StructType *STy = dyn_cast<StructType>(CurTy)) {
531 for (unsigned i = 0; i != Size; ++i)
532 Elts.push_back(ValueList.getConstantFwdRef(Record[i+1],
533 STy->getElementType(i)));
534 V = ConstantStruct::get(STy, Elts);
535 } else if (const ArrayType *ATy = dyn_cast<ArrayType>(CurTy)) {
536 const Type *EltTy = ATy->getElementType();
537 for (unsigned i = 0; i != Size; ++i)
538 Elts.push_back(ValueList.getConstantFwdRef(Record[i+1], EltTy));
539 V = ConstantArray::get(ATy, Elts);
540 } else if (const VectorType *VTy = dyn_cast<VectorType>(CurTy)) {
541 const Type *EltTy = VTy->getElementType();
542 for (unsigned i = 0; i != Size; ++i)
543 Elts.push_back(ValueList.getConstantFwdRef(Record[i+1], EltTy));
544 V = ConstantVector::get(Elts);
546 V = UndefValue::get(CurTy);
551 case bitc::CST_CODE_CE_BINOP: { // CE_BINOP: [opcode, opval, opval]
552 if (Record.size() < 3) return Error("Invalid CE_BINOP record");
553 int Opc = GetDecodedBinaryOpcode(Record[0], CurTy);
555 V = UndefValue::get(CurTy); // Unknown binop.
557 Constant *LHS = ValueList.getConstantFwdRef(Record[1], CurTy);
558 Constant *RHS = ValueList.getConstantFwdRef(Record[2], CurTy);
559 V = ConstantExpr::get(Opc, LHS, RHS);
563 case bitc::CST_CODE_CE_CAST: { // CE_CAST: [opcode, opty, opval]
564 if (Record.size() < 3) return Error("Invalid CE_CAST record");
565 int Opc = GetDecodedCastOpcode(Record[0]);
567 V = UndefValue::get(CurTy); // Unknown cast.
569 const Type *OpTy = getTypeByID(Record[1]);
570 Constant *Op = ValueList.getConstantFwdRef(Record[2], OpTy);
571 V = ConstantExpr::getCast(Opc, Op, CurTy);
575 case bitc::CST_CODE_CE_GEP: { // CE_GEP: [n x operands]
576 if ((Record.size() & 1) == 0) return Error("Invalid CE_GEP record");
577 SmallVector<Constant*, 16> Elts;
578 for (unsigned i = 1, e = Record.size(); i != e; i += 2) {
579 const Type *ElTy = getTypeByID(Record[i]);
580 if (!ElTy) return Error("Invalid CE_GEP record");
581 Elts.push_back(ValueList.getConstantFwdRef(Record[i+1], ElTy));
583 V = ConstantExpr::getGetElementPtr(Elts[0], &Elts[1], Elts.size()-1);
586 case bitc::CST_CODE_CE_SELECT: // CE_SELECT: [opval#, opval#, opval#]
587 if (Record.size() < 3) return Error("Invalid CE_SELECT record");
588 V = ConstantExpr::getSelect(ValueList.getConstantFwdRef(Record[0],
590 ValueList.getConstantFwdRef(Record[1],CurTy),
591 ValueList.getConstantFwdRef(Record[2],CurTy));
593 case bitc::CST_CODE_CE_EXTRACTELT: { // CE_EXTRACTELT: [opty, opval, opval]
594 if (Record.size() < 3) return Error("Invalid CE_EXTRACTELT record");
595 const VectorType *OpTy =
596 dyn_cast_or_null<VectorType>(getTypeByID(Record[0]));
597 if (OpTy == 0) return Error("Invalid CE_EXTRACTELT record");
598 Constant *Op0 = ValueList.getConstantFwdRef(Record[1], OpTy);
599 Constant *Op1 = ValueList.getConstantFwdRef(Record[2],
600 OpTy->getElementType());
601 V = ConstantExpr::getExtractElement(Op0, Op1);
604 case bitc::CST_CODE_CE_INSERTELT: { // CE_INSERTELT: [opval, opval, opval]
605 const VectorType *OpTy = dyn_cast<VectorType>(CurTy);
606 if (Record.size() < 3 || OpTy == 0)
607 return Error("Invalid CE_INSERTELT record");
608 Constant *Op0 = ValueList.getConstantFwdRef(Record[0], OpTy);
609 Constant *Op1 = ValueList.getConstantFwdRef(Record[1],
610 OpTy->getElementType());
611 Constant *Op2 = ValueList.getConstantFwdRef(Record[2], Type::Int32Ty);
612 V = ConstantExpr::getInsertElement(Op0, Op1, Op2);
615 case bitc::CST_CODE_CE_SHUFFLEVEC: { // CE_SHUFFLEVEC: [opval, opval, opval]
616 const VectorType *OpTy = dyn_cast<VectorType>(CurTy);
617 if (Record.size() < 3 || OpTy == 0)
618 return Error("Invalid CE_INSERTELT record");
619 Constant *Op0 = ValueList.getConstantFwdRef(Record[0], OpTy);
620 Constant *Op1 = ValueList.getConstantFwdRef(Record[1], OpTy);
621 const Type *ShufTy=VectorType::get(Type::Int32Ty, OpTy->getNumElements());
622 Constant *Op2 = ValueList.getConstantFwdRef(Record[2], ShufTy);
623 V = ConstantExpr::getShuffleVector(Op0, Op1, Op2);
626 case bitc::CST_CODE_CE_CMP: { // CE_CMP: [opty, opval, opval, pred]
627 if (Record.size() < 4) return Error("Invalid CE_CMP record");
628 const Type *OpTy = getTypeByID(Record[0]);
629 if (OpTy == 0) return Error("Invalid CE_CMP record");
630 Constant *Op0 = ValueList.getConstantFwdRef(Record[1], OpTy);
631 Constant *Op1 = ValueList.getConstantFwdRef(Record[2], OpTy);
633 if (OpTy->isFloatingPoint())
634 V = ConstantExpr::getFCmp(Record[3], Op0, Op1);
636 V = ConstantExpr::getICmp(Record[3], Op0, Op1);
641 if (NextCstNo == ValueList.size())
642 ValueList.push_back(V);
643 else if (ValueList[NextCstNo] == 0)
644 ValueList.initVal(NextCstNo, V);
646 // If there was a forward reference to this constant,
647 Value *OldV = ValueList[NextCstNo];
648 ValueList.setOperand(NextCstNo, V);
649 OldV->replaceAllUsesWith(V);
657 bool BitcodeReader::ParseModule(BitstreamReader &Stream,
658 const std::string &ModuleID) {
659 // Reject multiple MODULE_BLOCK's in a single bitstream.
661 return Error("Multiple MODULE_BLOCKs in same stream");
663 if (Stream.EnterSubBlock())
664 return Error("Malformed block record");
666 // Otherwise, create the module.
667 TheModule = new Module(ModuleID);
669 SmallVector<uint64_t, 64> Record;
670 std::vector<std::string> SectionTable;
672 // Read all the records for this module.
673 while (!Stream.AtEndOfStream()) {
674 unsigned Code = Stream.ReadCode();
675 if (Code == bitc::END_BLOCK) {
676 ResolveGlobalAndAliasInits();
677 if (!GlobalInits.empty() || !AliasInits.empty())
678 return Error("Malformed global initializer set");
679 if (Stream.ReadBlockEnd())
680 return Error("Error at end of module block");
684 if (Code == bitc::ENTER_SUBBLOCK) {
685 switch (Stream.ReadSubBlockID()) {
686 default: // Skip unknown content.
687 if (Stream.SkipBlock())
688 return Error("Malformed block record");
690 case bitc::TYPE_BLOCK_ID:
691 if (ParseTypeTable(Stream))
694 case bitc::TYPE_SYMTAB_BLOCK_ID:
695 if (ParseTypeSymbolTable(Stream))
698 case bitc::VALUE_SYMTAB_BLOCK_ID:
699 if (ParseValueSymbolTable(Stream))
702 case bitc::CONSTANTS_BLOCK_ID:
703 if (ParseConstants(Stream) || ResolveGlobalAndAliasInits())
710 if (Code == bitc::DEFINE_ABBREV) {
711 Stream.ReadAbbrevRecord();
716 switch (Stream.ReadRecord(Code, Record)) {
717 default: break; // Default behavior, ignore unknown content.
718 case bitc::MODULE_CODE_VERSION: // VERSION: [version#]
719 if (Record.size() < 1)
720 return Error("Malformed MODULE_CODE_VERSION");
721 // Only version #0 is supported so far.
723 return Error("Unknown bitstream version!");
725 case bitc::MODULE_CODE_TRIPLE: { // TRIPLE: [strlen, strchr x N]
727 if (ConvertToString(Record, 0, S))
728 return Error("Invalid MODULE_CODE_TRIPLE record");
729 TheModule->setTargetTriple(S);
732 case bitc::MODULE_CODE_DATALAYOUT: { // DATALAYOUT: [strlen, strchr x N]
734 if (ConvertToString(Record, 0, S))
735 return Error("Invalid MODULE_CODE_DATALAYOUT record");
736 TheModule->setDataLayout(S);
739 case bitc::MODULE_CODE_ASM: { // ASM: [strlen, strchr x N]
741 if (ConvertToString(Record, 0, S))
742 return Error("Invalid MODULE_CODE_ASM record");
743 TheModule->setModuleInlineAsm(S);
746 case bitc::MODULE_CODE_DEPLIB: { // DEPLIB: [strlen, strchr x N]
748 if (ConvertToString(Record, 0, S))
749 return Error("Invalid MODULE_CODE_DEPLIB record");
750 TheModule->addLibrary(S);
753 case bitc::MODULE_CODE_SECTIONNAME: { // SECTIONNAME: [strlen, strchr x N]
755 if (ConvertToString(Record, 0, S))
756 return Error("Invalid MODULE_CODE_SECTIONNAME record");
757 SectionTable.push_back(S);
760 // GLOBALVAR: [type, isconst, initid,
761 // linkage, alignment, section, visibility, threadlocal]
762 case bitc::MODULE_CODE_GLOBALVAR: {
763 if (Record.size() < 6)
764 return Error("Invalid MODULE_CODE_GLOBALVAR record");
765 const Type *Ty = getTypeByID(Record[0]);
766 if (!isa<PointerType>(Ty))
767 return Error("Global not a pointer type!");
768 Ty = cast<PointerType>(Ty)->getElementType();
770 bool isConstant = Record[1];
771 GlobalValue::LinkageTypes Linkage = GetDecodedLinkage(Record[3]);
772 unsigned Alignment = (1 << Record[4]) >> 1;
775 if (Record[5]-1 >= SectionTable.size())
776 return Error("Invalid section ID");
777 Section = SectionTable[Record[5]-1];
779 GlobalValue::VisibilityTypes Visibility = GlobalValue::DefaultVisibility;
780 if (Record.size() >= 6) Visibility = GetDecodedVisibility(Record[6]);
781 bool isThreadLocal = false;
782 if (Record.size() >= 7) isThreadLocal = Record[7];
784 GlobalVariable *NewGV =
785 new GlobalVariable(Ty, isConstant, Linkage, 0, "", TheModule);
786 NewGV->setAlignment(Alignment);
787 if (!Section.empty())
788 NewGV->setSection(Section);
789 NewGV->setVisibility(Visibility);
790 NewGV->setThreadLocal(isThreadLocal);
792 ValueList.push_back(NewGV);
794 // Remember which value to use for the global initializer.
795 if (unsigned InitID = Record[2])
796 GlobalInits.push_back(std::make_pair(NewGV, InitID-1));
799 // FUNCTION: [type, callingconv, isproto, linkage, alignment, section,
801 case bitc::MODULE_CODE_FUNCTION: {
802 if (Record.size() < 7)
803 return Error("Invalid MODULE_CODE_FUNCTION record");
804 const Type *Ty = getTypeByID(Record[0]);
805 if (!isa<PointerType>(Ty))
806 return Error("Function not a pointer type!");
807 const FunctionType *FTy =
808 dyn_cast<FunctionType>(cast<PointerType>(Ty)->getElementType());
810 return Error("Function not a pointer to function type!");
812 Function *Func = new Function(FTy, GlobalValue::ExternalLinkage,
815 Func->setCallingConv(Record[1]);
816 Func->setLinkage(GetDecodedLinkage(Record[3]));
817 Func->setAlignment((1 << Record[4]) >> 1);
819 if (Record[5]-1 >= SectionTable.size())
820 return Error("Invalid section ID");
821 Func->setSection(SectionTable[Record[5]-1]);
823 Func->setVisibility(GetDecodedVisibility(Record[6]));
825 ValueList.push_back(Func);
828 // ALIAS: [alias type, aliasee val#, linkage]
829 case bitc::MODULE_CODE_ALIAS: {
830 if (Record.size() < 3)
831 return Error("Invalid MODULE_ALIAS record");
832 const Type *Ty = getTypeByID(Record[0]);
833 if (!isa<PointerType>(Ty))
834 return Error("Function not a pointer type!");
836 GlobalAlias *NewGA = new GlobalAlias(Ty, GetDecodedLinkage(Record[2]),
838 ValueList.push_back(NewGA);
839 AliasInits.push_back(std::make_pair(NewGA, Record[1]));
842 /// MODULE_CODE_PURGEVALS: [numvals]
843 case bitc::MODULE_CODE_PURGEVALS:
844 // Trim down the value list to the specified size.
845 if (Record.size() < 1 || Record[0] > ValueList.size())
846 return Error("Invalid MODULE_PURGEVALS record");
847 ValueList.shrinkTo(Record[0]);
853 return Error("Premature end of bitstream");
857 bool BitcodeReader::ParseBitcode(unsigned char *Buf, unsigned Length,
858 const std::string &ModuleID) {
862 return Error("Bitcode stream should be a multiple of 4 bytes in length");
864 BitstreamReader Stream(Buf, Buf+Length);
866 // Sniff for the signature.
867 if (Stream.Read(8) != 'B' ||
868 Stream.Read(8) != 'C' ||
869 Stream.Read(4) != 0x0 ||
870 Stream.Read(4) != 0xC ||
871 Stream.Read(4) != 0xE ||
872 Stream.Read(4) != 0xD)
873 return Error("Invalid bitcode signature");
875 // We expect a number of well-defined blocks, though we don't necessarily
876 // need to understand them all.
877 while (!Stream.AtEndOfStream()) {
878 unsigned Code = Stream.ReadCode();
880 if (Code != bitc::ENTER_SUBBLOCK)
881 return Error("Invalid record at top-level");
883 unsigned BlockID = Stream.ReadSubBlockID();
885 // We only know the MODULE subblock ID.
886 if (BlockID == bitc::MODULE_BLOCK_ID) {
887 if (ParseModule(Stream, ModuleID))
889 } else if (Stream.SkipBlock()) {
890 return Error("Malformed block record");