//===--- Bitcode/Writer/Writer.cpp - Bitcode Writer -----------------------===// // // The LLVM Compiler Infrastructure // // This file was developed by Chris Lattner and is distributed under // the University of Illinois Open Source License. See LICENSE.TXT for details. // //===----------------------------------------------------------------------===// // // Bitcode writer implementation. // //===----------------------------------------------------------------------===// #include "llvm/Bitcode/ReaderWriter.h" #include "llvm/Bitcode/BitstreamWriter.h" #include "llvm/Bitcode/LLVMBitCodes.h" #include "ValueEnumerator.h" #include "llvm/Constants.h" #include "llvm/DerivedTypes.h" #include "llvm/Module.h" #include "llvm/TypeSymbolTable.h" #include "llvm/ValueSymbolTable.h" #include "llvm/Support/MathExtras.h" using namespace llvm; static const unsigned CurVersion = 0; static unsigned GetEncodedCastOpcode(unsigned Opcode) { switch (Opcode) { default: assert(0 && "Unknown cast instruction!"); case Instruction::Trunc : return bitc::CAST_TRUNC; case Instruction::ZExt : return bitc::CAST_ZEXT; case Instruction::SExt : return bitc::CAST_SEXT; case Instruction::FPToUI : return bitc::CAST_FPTOUI; case Instruction::FPToSI : return bitc::CAST_FPTOSI; case Instruction::UIToFP : return bitc::CAST_UITOFP; case Instruction::SIToFP : return bitc::CAST_SITOFP; case Instruction::FPTrunc : return bitc::CAST_FPTRUNC; case Instruction::FPExt : return bitc::CAST_FPEXT; case Instruction::PtrToInt: return bitc::CAST_PTRTOINT; case Instruction::IntToPtr: return bitc::CAST_INTTOPTR; case Instruction::BitCast : return bitc::CAST_BITCAST; } } static unsigned GetEncodedBinaryOpcode(unsigned Opcode) { switch (Opcode) { default: assert(0 && "Unknown binary instruction!"); case Instruction::Add: return bitc::BINOP_ADD; case Instruction::Sub: return bitc::BINOP_SUB; case Instruction::Mul: return bitc::BINOP_MUL; case Instruction::UDiv: return bitc::BINOP_UDIV; case Instruction::FDiv: case Instruction::SDiv: return bitc::BINOP_SDIV; case Instruction::URem: return bitc::BINOP_UREM; case Instruction::FRem: case Instruction::SRem: return bitc::BINOP_SREM; case Instruction::Shl: return bitc::BINOP_SHL; case Instruction::LShr: return bitc::BINOP_LSHR; case Instruction::AShr: return bitc::BINOP_ASHR; case Instruction::And: return bitc::BINOP_AND; case Instruction::Or: return bitc::BINOP_OR; case Instruction::Xor: return bitc::BINOP_XOR; } } static void WriteStringRecord(unsigned Code, const std::string &Str, unsigned AbbrevToUse, BitstreamWriter &Stream) { SmallVector Vals; // Code: [strlen, strchar x N] Vals.push_back(Str.size()); for (unsigned i = 0, e = Str.size(); i != e; ++i) Vals.push_back(Str[i]); // Emit the finished record. Stream.EmitRecord(Code, Vals, AbbrevToUse); } /// WriteTypeTable - Write out the type table for a module. static void WriteTypeTable(const ValueEnumerator &VE, BitstreamWriter &Stream) { const ValueEnumerator::TypeList &TypeList = VE.getTypes(); Stream.EnterSubblock(bitc::TYPE_BLOCK_ID, 4 /*count from # abbrevs */); SmallVector TypeVals; // FIXME: Set up abbrevs now that we know the width of the type fields, etc. // Emit an entry count so the reader can reserve space. TypeVals.push_back(TypeList.size()); Stream.EmitRecord(bitc::TYPE_CODE_NUMENTRY, TypeVals); TypeVals.clear(); // Loop over all of the types, emitting each in turn. for (unsigned i = 0, e = TypeList.size(); i != e; ++i) { const Type *T = TypeList[i].first; int AbbrevToUse = 0; unsigned Code = 0; switch (T->getTypeID()) { case Type::PackedStructTyID: // FIXME: Delete Type::PackedStructTyID. default: assert(0 && "Unknown type!"); case Type::VoidTyID: Code = bitc::TYPE_CODE_VOID; break; case Type::FloatTyID: Code = bitc::TYPE_CODE_FLOAT; break; case Type::DoubleTyID: Code = bitc::TYPE_CODE_DOUBLE; break; case Type::LabelTyID: Code = bitc::TYPE_CODE_LABEL; break; case Type::OpaqueTyID: Code = bitc::TYPE_CODE_OPAQUE; break; case Type::IntegerTyID: // INTEGER: [width] Code = bitc::TYPE_CODE_INTEGER; TypeVals.push_back(cast(T)->getBitWidth()); break; case Type::PointerTyID: // POINTER: [pointee type] Code = bitc::TYPE_CODE_POINTER; TypeVals.push_back(VE.getTypeID(cast(T)->getElementType())); break; case Type::FunctionTyID: { const FunctionType *FT = cast(T); // FUNCTION: [isvararg, #pararms, paramty x N] Code = bitc::TYPE_CODE_FUNCTION; TypeVals.push_back(FT->isVarArg()); TypeVals.push_back(VE.getTypeID(FT->getReturnType())); // FIXME: PARAM ATTR ID! TypeVals.push_back(FT->getNumParams()); for (unsigned i = 0, e = FT->getNumParams(); i != e; ++i) TypeVals.push_back(VE.getTypeID(FT->getParamType(i))); break; } case Type::StructTyID: { const StructType *ST = cast(T); // STRUCT: [ispacked, #elts, eltty x N] Code = bitc::TYPE_CODE_STRUCT; TypeVals.push_back(ST->isPacked()); TypeVals.push_back(ST->getNumElements()); // Output all of the element types... for (StructType::element_iterator I = ST->element_begin(), E = ST->element_end(); I != E; ++I) TypeVals.push_back(VE.getTypeID(*I)); break; } case Type::ArrayTyID: { const ArrayType *AT = cast(T); // ARRAY: [numelts, eltty] Code = bitc::TYPE_CODE_ARRAY; TypeVals.push_back(AT->getNumElements()); TypeVals.push_back(VE.getTypeID(AT->getElementType())); break; } case Type::VectorTyID: { const VectorType *VT = cast(T); // VECTOR [numelts, eltty] Code = bitc::TYPE_CODE_VECTOR; TypeVals.push_back(VT->getNumElements()); TypeVals.push_back(VE.getTypeID(VT->getElementType())); break; } } // Emit the finished record. Stream.EmitRecord(Code, TypeVals, AbbrevToUse); TypeVals.clear(); } Stream.ExitBlock(); } static unsigned getEncodedLinkage(const GlobalValue *GV) { switch (GV->getLinkage()) { default: assert(0 && "Invalid linkage!"); case GlobalValue::ExternalLinkage: return 0; case GlobalValue::WeakLinkage: return 1; case GlobalValue::AppendingLinkage: return 2; case GlobalValue::InternalLinkage: return 3; case GlobalValue::LinkOnceLinkage: return 4; case GlobalValue::DLLImportLinkage: return 5; case GlobalValue::DLLExportLinkage: return 6; case GlobalValue::ExternalWeakLinkage: return 7; } } static unsigned getEncodedVisibility(const GlobalValue *GV) { switch (GV->getVisibility()) { default: assert(0 && "Invalid visibility!"); case GlobalValue::DefaultVisibility: return 0; case GlobalValue::HiddenVisibility: return 1; } } // Emit top-level description of module, including target triple, inline asm, // descriptors for global variables, and function prototype info. static void WriteModuleInfo(const Module *M, const ValueEnumerator &VE, BitstreamWriter &Stream) { // Emit the list of dependent libraries for the Module. for (Module::lib_iterator I = M->lib_begin(), E = M->lib_end(); I != E; ++I) WriteStringRecord(bitc::MODULE_CODE_DEPLIB, *I, 0/*TODO*/, Stream); // Emit various pieces of data attached to a module. if (!M->getTargetTriple().empty()) WriteStringRecord(bitc::MODULE_CODE_TRIPLE, M->getTargetTriple(), 0/*TODO*/, Stream); if (!M->getDataLayout().empty()) WriteStringRecord(bitc::MODULE_CODE_DATALAYOUT, M->getDataLayout(), 0/*TODO*/, Stream); if (!M->getModuleInlineAsm().empty()) WriteStringRecord(bitc::MODULE_CODE_ASM, M->getModuleInlineAsm(), 0/*TODO*/, Stream); // Emit information about sections, computing how many there are. Also // compute the maximum alignment value. std::map SectionMap; unsigned MaxAlignment = 0; unsigned MaxGlobalType = 0; for (Module::const_global_iterator GV = M->global_begin(),E = M->global_end(); GV != E; ++GV) { MaxAlignment = std::max(MaxAlignment, GV->getAlignment()); MaxGlobalType = std::max(MaxGlobalType, VE.getTypeID(GV->getType())); if (!GV->hasSection()) continue; // Give section names unique ID's. unsigned &Entry = SectionMap[GV->getSection()]; if (Entry != 0) continue; WriteStringRecord(bitc::MODULE_CODE_SECTIONNAME, GV->getSection(), 0/*TODO*/, Stream); Entry = SectionMap.size(); } for (Module::const_iterator F = M->begin(), E = M->end(); F != E; ++F) { MaxAlignment = std::max(MaxAlignment, F->getAlignment()); if (!F->hasSection()) continue; // Give section names unique ID's. unsigned &Entry = SectionMap[F->getSection()]; if (Entry != 0) continue; WriteStringRecord(bitc::MODULE_CODE_SECTIONNAME, F->getSection(), 0/*TODO*/, Stream); Entry = SectionMap.size(); } // Emit abbrev for globals, now that we know # sections and max alignment. unsigned SimpleGVarAbbrev = 0; if (!M->global_empty()) { // Add an abbrev for common globals with no visibility or thread localness. BitCodeAbbrev *Abbv = new BitCodeAbbrev(); Abbv->Add(BitCodeAbbrevOp(bitc::MODULE_CODE_GLOBALVAR)); Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::FixedWidth, Log2_32_Ceil(MaxGlobalType+1))); Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::FixedWidth, 1)); // Constant. Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Initializer. Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::FixedWidth, 3)); // Linkage. if (MaxAlignment == 0) // Alignment. Abbv->Add(BitCodeAbbrevOp(0)); else { unsigned MaxEncAlignment = Log2_32(MaxAlignment)+1; Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::FixedWidth, Log2_32_Ceil(MaxEncAlignment+1))); } if (SectionMap.empty()) // Section. Abbv->Add(BitCodeAbbrevOp(0)); else Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::FixedWidth, Log2_32_Ceil(SectionMap.size()+1))); // Don't bother emitting vis + thread local. SimpleGVarAbbrev = Stream.EmitAbbrev(Abbv); } // Emit the global variable information. SmallVector Vals; for (Module::const_global_iterator GV = M->global_begin(),E = M->global_end(); GV != E; ++GV) { unsigned AbbrevToUse = 0; // GLOBALVAR: [type, isconst, initid, // linkage, alignment, section, visibility, threadlocal] Vals.push_back(VE.getTypeID(GV->getType())); Vals.push_back(GV->isConstant()); Vals.push_back(GV->isDeclaration() ? 0 : (VE.getValueID(GV->getInitializer()) + 1)); Vals.push_back(getEncodedLinkage(GV)); Vals.push_back(Log2_32(GV->getAlignment())+1); Vals.push_back(GV->hasSection() ? SectionMap[GV->getSection()] : 0); if (GV->isThreadLocal() || GV->getVisibility() != GlobalValue::DefaultVisibility) { Vals.push_back(getEncodedVisibility(GV)); Vals.push_back(GV->isThreadLocal()); } else { AbbrevToUse = SimpleGVarAbbrev; } Stream.EmitRecord(bitc::MODULE_CODE_GLOBALVAR, Vals, AbbrevToUse); Vals.clear(); } // Emit the function proto information. for (Module::const_iterator F = M->begin(), E = M->end(); F != E; ++F) { // FUNCTION: [type, callingconv, isproto, linkage, alignment, section, // visibility] Vals.push_back(VE.getTypeID(F->getType())); Vals.push_back(F->getCallingConv()); Vals.push_back(F->isDeclaration()); Vals.push_back(getEncodedLinkage(F)); Vals.push_back(Log2_32(F->getAlignment())+1); Vals.push_back(F->hasSection() ? SectionMap[F->getSection()] : 0); Vals.push_back(getEncodedVisibility(F)); unsigned AbbrevToUse = 0; Stream.EmitRecord(bitc::MODULE_CODE_FUNCTION, Vals, AbbrevToUse); Vals.clear(); } } /// WriteTypeSymbolTable - Emit a block for the specified type symtab. static void WriteTypeSymbolTable(const TypeSymbolTable &TST, const ValueEnumerator &VE, BitstreamWriter &Stream) { if (TST.empty()) return; Stream.EnterSubblock(bitc::TYPE_SYMTAB_BLOCK_ID, 3); // FIXME: Set up the abbrev, we know how many types there are! // FIXME: We know if the type names can use 7-bit ascii. SmallVector NameVals; for (TypeSymbolTable::const_iterator TI = TST.begin(), TE = TST.end(); TI != TE; ++TI) { unsigned AbbrevToUse = 0; // TST_ENTRY: [typeid, namelen, namechar x N] NameVals.push_back(VE.getTypeID(TI->second)); const std::string &Str = TI->first; NameVals.push_back(Str.size()); for (unsigned i = 0, e = Str.size(); i != e; ++i) NameVals.push_back(Str[i]); // Emit the finished record. Stream.EmitRecord(bitc::VST_CODE_ENTRY, NameVals, AbbrevToUse); NameVals.clear(); } Stream.ExitBlock(); } // Emit names for globals/functions etc. static void WriteValueSymbolTable(const ValueSymbolTable &VST, const ValueEnumerator &VE, BitstreamWriter &Stream) { if (VST.empty()) return; Stream.EnterSubblock(bitc::VALUE_SYMTAB_BLOCK_ID, 3); // FIXME: Set up the abbrev, we know how many values there are! // FIXME: We know if the type names can use 7-bit ascii. SmallVector NameVals; for (ValueSymbolTable::const_iterator SI = VST.begin(), SE = VST.end(); SI != SE; ++SI) { unsigned AbbrevToUse = 0; // VST_ENTRY: [valueid, namelen, namechar x N] NameVals.push_back(VE.getValueID(SI->getValue())); NameVals.push_back(SI->getKeyLength()); for (const char *P = SI->getKeyData(), *E = SI->getKeyData()+SI->getKeyLength(); P != E; ++P) NameVals.push_back((unsigned char)*P); // Emit the finished record. Stream.EmitRecord(bitc::VST_CODE_ENTRY, NameVals, AbbrevToUse); NameVals.clear(); } Stream.ExitBlock(); } static void WriteConstants(unsigned FirstVal, unsigned LastVal, const ValueEnumerator &VE, BitstreamWriter &Stream) { if (FirstVal == LastVal) return; Stream.EnterSubblock(bitc::CONSTANTS_BLOCK_ID, 2); // FIXME: Install and use abbrevs to reduce size. SmallVector Record; const ValueEnumerator::ValueList &Vals = VE.getValues(); const Type *LastTy = 0; for (unsigned i = FirstVal; i != LastVal; ++i) { const Value *V = Vals[i].first; // If we need to switch types, do so now. if (V->getType() != LastTy) { LastTy = V->getType(); Record.push_back(VE.getTypeID(LastTy)); Stream.EmitRecord(bitc::CST_CODE_SETTYPE, Record); Record.clear(); } if (const InlineAsm *IA = dyn_cast(V)) { assert(0 && IA && "FIXME: Inline asm writing unimp!"); continue; } const Constant *C = cast(V); unsigned Code = -1U; unsigned AbbrevToUse = 0; if (C->isNullValue()) { Code = bitc::CST_CODE_NULL; } else if (isa(C)) { Code = bitc::CST_CODE_UNDEF; } else if (const ConstantInt *IV = dyn_cast(C)) { if (IV->getBitWidth() <= 64) { int64_t V = IV->getSExtValue(); if (V >= 0) Record.push_back(V << 1); else Record.push_back((-V << 1) | 1); Code = bitc::CST_CODE_INTEGER; } else { // Wide integers, > 64 bits in size. // We have an arbitrary precision integer value to write whose // bit width is > 64. However, in canonical unsigned integer // format it is likely that the high bits are going to be zero. // So, we only write the number of active words. unsigned NWords = IV->getValue().getActiveWords(); const uint64_t *RawWords = IV->getValue().getRawData(); Record.push_back(NWords); for (unsigned i = 0; i != NWords; ++i) { int64_t V = RawWords[i]; if (V >= 0) Record.push_back(V << 1); else Record.push_back((-V << 1) | 1); } Code = bitc::CST_CODE_WIDE_INTEGER; } } else if (const ConstantFP *CFP = dyn_cast(C)) { Code = bitc::CST_CODE_FLOAT; if (CFP->getType() == Type::FloatTy) { Record.push_back(FloatToBits((float)CFP->getValue())); } else { assert (CFP->getType() == Type::DoubleTy && "Unknown FP type!"); Record.push_back(DoubleToBits((double)CFP->getValue())); } } else if (isa(C) || isa(V) || isa(V)) { Code = bitc::CST_CODE_AGGREGATE; Record.push_back(C->getNumOperands()); for (unsigned i = 0, e = C->getNumOperands(); i != e; ++i) Record.push_back(VE.getValueID(C->getOperand(i))); } else if (const ConstantExpr *CE = dyn_cast(C)) { switch (CE->getOpcode()) { default: if (Instruction::isCast(CE->getOpcode())) { Code = bitc::CST_CODE_CE_CAST; Record.push_back(GetEncodedCastOpcode(CE->getOpcode())); Record.push_back(VE.getTypeID(C->getOperand(0)->getType())); Record.push_back(VE.getValueID(C->getOperand(0))); } else { assert(CE->getNumOperands() == 2 && "Unknown constant expr!"); Code = bitc::CST_CODE_CE_BINOP; Record.push_back(GetEncodedBinaryOpcode(CE->getOpcode())); Record.push_back(VE.getValueID(C->getOperand(0))); Record.push_back(VE.getValueID(C->getOperand(1))); } break; case Instruction::GetElementPtr: Code = bitc::CST_CODE_CE_GEP; Record.push_back(CE->getNumOperands()); for (unsigned i = 0, e = CE->getNumOperands(); i != e; ++i) { Record.push_back(VE.getTypeID(C->getOperand(i)->getType())); Record.push_back(VE.getValueID(C->getOperand(i))); } break; case Instruction::Select: Code = bitc::CST_CODE_CE_SELECT; Record.push_back(VE.getValueID(C->getOperand(0))); Record.push_back(VE.getValueID(C->getOperand(1))); Record.push_back(VE.getValueID(C->getOperand(2))); break; case Instruction::ExtractElement: Code = bitc::CST_CODE_CE_EXTRACTELT; Record.push_back(VE.getTypeID(C->getOperand(0)->getType())); Record.push_back(VE.getValueID(C->getOperand(0))); Record.push_back(VE.getValueID(C->getOperand(1))); break; case Instruction::InsertElement: Code = bitc::CST_CODE_CE_INSERTELT; Record.push_back(VE.getValueID(C->getOperand(0))); Record.push_back(VE.getValueID(C->getOperand(1))); Record.push_back(VE.getValueID(C->getOperand(2))); break; case Instruction::ShuffleVector: Code = bitc::CST_CODE_CE_SHUFFLEVEC; Record.push_back(VE.getValueID(C->getOperand(0))); Record.push_back(VE.getValueID(C->getOperand(1))); Record.push_back(VE.getValueID(C->getOperand(2))); break; case Instruction::ICmp: case Instruction::FCmp: Code = bitc::CST_CODE_CE_CMP; Record.push_back(VE.getTypeID(C->getOperand(0)->getType())); Record.push_back(VE.getValueID(C->getOperand(0))); Record.push_back(VE.getValueID(C->getOperand(1))); Record.push_back(CE->getPredicate()); break; } } else { assert(0 && "Unknown constant!"); } Stream.EmitRecord(Code, Record, AbbrevToUse); Record.clear(); } Stream.ExitBlock(); } static void WriteModuleConstants(const ValueEnumerator &VE, BitstreamWriter &Stream) { const ValueEnumerator::ValueList &Vals = VE.getValues(); // Find the first constant to emit, which is the first non-globalvalue value. // We know globalvalues have been emitted by WriteModuleInfo. for (unsigned i = 0, e = Vals.size(); i != e; ++i) { if (!isa(Vals[i].first)) { WriteConstants(i, Vals.size(), VE, Stream); return; } } } /// WriteModule - Emit the specified module to the bitstream. static void WriteModule(const Module *M, BitstreamWriter &Stream) { Stream.EnterSubblock(bitc::MODULE_BLOCK_ID, 3); // Emit the version number if it is non-zero. if (CurVersion) { SmallVector VersionVals; VersionVals.push_back(CurVersion); Stream.EmitRecord(bitc::MODULE_CODE_VERSION, VersionVals); } // Analyze the module, enumerating globals, functions, etc. ValueEnumerator VE(M); // Emit information describing all of the types in the module. WriteTypeTable(VE, Stream); // Emit top-level description of module, including target triple, inline asm, // descriptors for global variables, and function prototype info. WriteModuleInfo(M, VE, Stream); // Emit constants. WriteModuleConstants(VE, Stream); // Emit the type symbol table information. WriteTypeSymbolTable(M->getTypeSymbolTable(), VE, Stream); // Emit names for globals/functions etc. WriteValueSymbolTable(M->getValueSymbolTable(), VE, Stream); Stream.ExitBlock(); } /// WriteBitcodeToFile - Write the specified module to the specified output /// stream. void llvm::WriteBitcodeToFile(const Module *M, std::ostream &Out) { std::vector Buffer; BitstreamWriter Stream(Buffer); Buffer.reserve(256*1024); // Emit the file header. Stream.Emit((unsigned)'B', 8); Stream.Emit((unsigned)'C', 8); Stream.Emit(0x0, 4); Stream.Emit(0xC, 4); Stream.Emit(0xE, 4); Stream.Emit(0xD, 4); // Emit the module. WriteModule(M, Stream); // Write the generated bitstream to "Out". Out.write((char*)&Buffer.front(), Buffer.size()); }