1 //===--- Bitcode/Writer/BitcodeWriter.cpp - Bitcode Writer ----------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // Bitcode writer implementation.
12 //===----------------------------------------------------------------------===//
14 #include "llvm/Bitcode/ReaderWriter.h"
15 #include "llvm/Bitcode/BitstreamWriter.h"
16 #include "llvm/Bitcode/LLVMBitCodes.h"
17 #include "ValueEnumerator.h"
18 #include "llvm/Constants.h"
19 #include "llvm/DerivedTypes.h"
20 #include "llvm/InlineAsm.h"
21 #include "llvm/Instructions.h"
22 #include "llvm/LLVMContext.h"
23 #include "llvm/Metadata.h"
24 #include "llvm/Module.h"
25 #include "llvm/Operator.h"
26 #include "llvm/TypeSymbolTable.h"
27 #include "llvm/ValueSymbolTable.h"
28 #include "llvm/Support/ErrorHandling.h"
29 #include "llvm/Support/MathExtras.h"
30 #include "llvm/Support/raw_ostream.h"
31 #include "llvm/System/Program.h"
34 /// These are manifest constants used by the bitcode writer. They do not need to
35 /// be kept in sync with the reader, but need to be consistent within this file.
39 // VALUE_SYMTAB_BLOCK abbrev id's.
40 VST_ENTRY_8_ABBREV = bitc::FIRST_APPLICATION_ABBREV,
45 // CONSTANTS_BLOCK abbrev id's.
46 CONSTANTS_SETTYPE_ABBREV = bitc::FIRST_APPLICATION_ABBREV,
47 CONSTANTS_INTEGER_ABBREV,
48 CONSTANTS_CE_CAST_Abbrev,
49 CONSTANTS_NULL_Abbrev,
51 // FUNCTION_BLOCK abbrev id's.
52 FUNCTION_INST_LOAD_ABBREV = bitc::FIRST_APPLICATION_ABBREV,
53 FUNCTION_INST_BINOP_ABBREV,
54 FUNCTION_INST_BINOP_FLAGS_ABBREV,
55 FUNCTION_INST_CAST_ABBREV,
56 FUNCTION_INST_RET_VOID_ABBREV,
57 FUNCTION_INST_RET_VAL_ABBREV,
58 FUNCTION_INST_UNREACHABLE_ABBREV
62 static unsigned GetEncodedCastOpcode(unsigned Opcode) {
64 default: llvm_unreachable("Unknown cast instruction!");
65 case Instruction::Trunc : return bitc::CAST_TRUNC;
66 case Instruction::ZExt : return bitc::CAST_ZEXT;
67 case Instruction::SExt : return bitc::CAST_SEXT;
68 case Instruction::FPToUI : return bitc::CAST_FPTOUI;
69 case Instruction::FPToSI : return bitc::CAST_FPTOSI;
70 case Instruction::UIToFP : return bitc::CAST_UITOFP;
71 case Instruction::SIToFP : return bitc::CAST_SITOFP;
72 case Instruction::FPTrunc : return bitc::CAST_FPTRUNC;
73 case Instruction::FPExt : return bitc::CAST_FPEXT;
74 case Instruction::PtrToInt: return bitc::CAST_PTRTOINT;
75 case Instruction::IntToPtr: return bitc::CAST_INTTOPTR;
76 case Instruction::BitCast : return bitc::CAST_BITCAST;
80 static unsigned GetEncodedBinaryOpcode(unsigned Opcode) {
82 default: llvm_unreachable("Unknown binary instruction!");
83 case Instruction::Add:
84 case Instruction::FAdd: return bitc::BINOP_ADD;
85 case Instruction::Sub:
86 case Instruction::FSub: return bitc::BINOP_SUB;
87 case Instruction::Mul:
88 case Instruction::FMul: return bitc::BINOP_MUL;
89 case Instruction::UDiv: return bitc::BINOP_UDIV;
90 case Instruction::FDiv:
91 case Instruction::SDiv: return bitc::BINOP_SDIV;
92 case Instruction::URem: return bitc::BINOP_UREM;
93 case Instruction::FRem:
94 case Instruction::SRem: return bitc::BINOP_SREM;
95 case Instruction::Shl: return bitc::BINOP_SHL;
96 case Instruction::LShr: return bitc::BINOP_LSHR;
97 case Instruction::AShr: return bitc::BINOP_ASHR;
98 case Instruction::And: return bitc::BINOP_AND;
99 case Instruction::Or: return bitc::BINOP_OR;
100 case Instruction::Xor: return bitc::BINOP_XOR;
106 static void WriteStringRecord(unsigned Code, const std::string &Str,
107 unsigned AbbrevToUse, BitstreamWriter &Stream) {
108 SmallVector<unsigned, 64> Vals;
110 // Code: [strchar x N]
111 for (unsigned i = 0, e = Str.size(); i != e; ++i)
112 Vals.push_back(Str[i]);
114 // Emit the finished record.
115 Stream.EmitRecord(Code, Vals, AbbrevToUse);
118 // Emit information about parameter attributes.
119 static void WriteAttributeTable(const ValueEnumerator &VE,
120 BitstreamWriter &Stream) {
121 const std::vector<AttrListPtr> &Attrs = VE.getAttributes();
122 if (Attrs.empty()) return;
124 Stream.EnterSubblock(bitc::PARAMATTR_BLOCK_ID, 3);
126 SmallVector<uint64_t, 64> Record;
127 for (unsigned i = 0, e = Attrs.size(); i != e; ++i) {
128 const AttrListPtr &A = Attrs[i];
129 for (unsigned i = 0, e = A.getNumSlots(); i != e; ++i) {
130 const AttributeWithIndex &PAWI = A.getSlot(i);
131 Record.push_back(PAWI.Index);
133 // FIXME: remove in LLVM 3.0
134 // Store the alignment in the bitcode as a 16-bit raw value instead of a
135 // 5-bit log2 encoded value. Shift the bits above the alignment up by
137 uint64_t FauxAttr = PAWI.Attrs & 0xffff;
138 if (PAWI.Attrs & Attribute::Alignment)
139 FauxAttr |= (1ull<<16)<<(((PAWI.Attrs & Attribute::Alignment)-1) >> 16);
140 FauxAttr |= (PAWI.Attrs & (0x3FFull << 21)) << 11;
142 Record.push_back(FauxAttr);
145 Stream.EmitRecord(bitc::PARAMATTR_CODE_ENTRY, Record);
152 /// WriteTypeTable - Write out the type table for a module.
153 static void WriteTypeTable(const ValueEnumerator &VE, BitstreamWriter &Stream) {
154 const ValueEnumerator::TypeList &TypeList = VE.getTypes();
156 Stream.EnterSubblock(bitc::TYPE_BLOCK_ID, 4 /*count from # abbrevs */);
157 SmallVector<uint64_t, 64> TypeVals;
159 // Abbrev for TYPE_CODE_POINTER.
160 BitCodeAbbrev *Abbv = new BitCodeAbbrev();
161 Abbv->Add(BitCodeAbbrevOp(bitc::TYPE_CODE_POINTER));
162 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
163 Log2_32_Ceil(VE.getTypes().size()+1)));
164 Abbv->Add(BitCodeAbbrevOp(0)); // Addrspace = 0
165 unsigned PtrAbbrev = Stream.EmitAbbrev(Abbv);
167 // Abbrev for TYPE_CODE_FUNCTION.
168 Abbv = new BitCodeAbbrev();
169 Abbv->Add(BitCodeAbbrevOp(bitc::TYPE_CODE_FUNCTION));
170 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isvararg
171 Abbv->Add(BitCodeAbbrevOp(0)); // FIXME: DEAD value, remove in LLVM 3.0
172 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
173 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
174 Log2_32_Ceil(VE.getTypes().size()+1)));
175 unsigned FunctionAbbrev = Stream.EmitAbbrev(Abbv);
177 // Abbrev for TYPE_CODE_STRUCT.
178 Abbv = new BitCodeAbbrev();
179 Abbv->Add(BitCodeAbbrevOp(bitc::TYPE_CODE_STRUCT));
180 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // ispacked
181 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
182 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
183 Log2_32_Ceil(VE.getTypes().size()+1)));
184 unsigned StructAbbrev = Stream.EmitAbbrev(Abbv);
186 // Abbrev for TYPE_CODE_ARRAY.
187 Abbv = new BitCodeAbbrev();
188 Abbv->Add(BitCodeAbbrevOp(bitc::TYPE_CODE_ARRAY));
189 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8)); // size
190 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
191 Log2_32_Ceil(VE.getTypes().size()+1)));
192 unsigned ArrayAbbrev = Stream.EmitAbbrev(Abbv);
194 // Emit an entry count so the reader can reserve space.
195 TypeVals.push_back(TypeList.size());
196 Stream.EmitRecord(bitc::TYPE_CODE_NUMENTRY, TypeVals);
199 // Loop over all of the types, emitting each in turn.
200 for (unsigned i = 0, e = TypeList.size(); i != e; ++i) {
201 const Type *T = TypeList[i].first;
205 switch (T->getTypeID()) {
206 default: llvm_unreachable("Unknown type!");
207 case Type::VoidTyID: Code = bitc::TYPE_CODE_VOID; break;
208 case Type::FloatTyID: Code = bitc::TYPE_CODE_FLOAT; break;
209 case Type::DoubleTyID: Code = bitc::TYPE_CODE_DOUBLE; break;
210 case Type::X86_FP80TyID: Code = bitc::TYPE_CODE_X86_FP80; break;
211 case Type::FP128TyID: Code = bitc::TYPE_CODE_FP128; break;
212 case Type::PPC_FP128TyID: Code = bitc::TYPE_CODE_PPC_FP128; break;
213 case Type::LabelTyID: Code = bitc::TYPE_CODE_LABEL; break;
214 case Type::OpaqueTyID: Code = bitc::TYPE_CODE_OPAQUE; break;
215 case Type::MetadataTyID: Code = bitc::TYPE_CODE_METADATA; break;
216 case Type::IntegerTyID:
218 Code = bitc::TYPE_CODE_INTEGER;
219 TypeVals.push_back(cast<IntegerType>(T)->getBitWidth());
221 case Type::PointerTyID: {
222 const PointerType *PTy = cast<PointerType>(T);
223 // POINTER: [pointee type, address space]
224 Code = bitc::TYPE_CODE_POINTER;
225 TypeVals.push_back(VE.getTypeID(PTy->getElementType()));
226 unsigned AddressSpace = PTy->getAddressSpace();
227 TypeVals.push_back(AddressSpace);
228 if (AddressSpace == 0) AbbrevToUse = PtrAbbrev;
231 case Type::FunctionTyID: {
232 const FunctionType *FT = cast<FunctionType>(T);
233 // FUNCTION: [isvararg, attrid, retty, paramty x N]
234 Code = bitc::TYPE_CODE_FUNCTION;
235 TypeVals.push_back(FT->isVarArg());
236 TypeVals.push_back(0); // FIXME: DEAD: remove in llvm 3.0
237 TypeVals.push_back(VE.getTypeID(FT->getReturnType()));
238 for (unsigned i = 0, e = FT->getNumParams(); i != e; ++i)
239 TypeVals.push_back(VE.getTypeID(FT->getParamType(i)));
240 AbbrevToUse = FunctionAbbrev;
243 case Type::StructTyID: {
244 const StructType *ST = cast<StructType>(T);
245 // STRUCT: [ispacked, eltty x N]
246 Code = bitc::TYPE_CODE_STRUCT;
247 TypeVals.push_back(ST->isPacked());
248 // Output all of the element types.
249 for (StructType::element_iterator I = ST->element_begin(),
250 E = ST->element_end(); I != E; ++I)
251 TypeVals.push_back(VE.getTypeID(*I));
252 AbbrevToUse = StructAbbrev;
255 case Type::ArrayTyID: {
256 const ArrayType *AT = cast<ArrayType>(T);
257 // ARRAY: [numelts, eltty]
258 Code = bitc::TYPE_CODE_ARRAY;
259 TypeVals.push_back(AT->getNumElements());
260 TypeVals.push_back(VE.getTypeID(AT->getElementType()));
261 AbbrevToUse = ArrayAbbrev;
264 case Type::VectorTyID: {
265 const VectorType *VT = cast<VectorType>(T);
266 // VECTOR [numelts, eltty]
267 Code = bitc::TYPE_CODE_VECTOR;
268 TypeVals.push_back(VT->getNumElements());
269 TypeVals.push_back(VE.getTypeID(VT->getElementType()));
274 // Emit the finished record.
275 Stream.EmitRecord(Code, TypeVals, AbbrevToUse);
282 static unsigned getEncodedLinkage(const GlobalValue *GV) {
283 switch (GV->getLinkage()) {
284 default: llvm_unreachable("Invalid linkage!");
285 case GlobalValue::GhostLinkage: // Map ghost linkage onto external.
286 case GlobalValue::ExternalLinkage: return 0;
287 case GlobalValue::WeakAnyLinkage: return 1;
288 case GlobalValue::AppendingLinkage: return 2;
289 case GlobalValue::InternalLinkage: return 3;
290 case GlobalValue::LinkOnceAnyLinkage: return 4;
291 case GlobalValue::DLLImportLinkage: return 5;
292 case GlobalValue::DLLExportLinkage: return 6;
293 case GlobalValue::ExternalWeakLinkage: return 7;
294 case GlobalValue::CommonLinkage: return 8;
295 case GlobalValue::PrivateLinkage: return 9;
296 case GlobalValue::WeakODRLinkage: return 10;
297 case GlobalValue::LinkOnceODRLinkage: return 11;
298 case GlobalValue::AvailableExternallyLinkage: return 12;
299 case GlobalValue::LinkerPrivateLinkage: return 13;
303 static unsigned getEncodedVisibility(const GlobalValue *GV) {
304 switch (GV->getVisibility()) {
305 default: llvm_unreachable("Invalid visibility!");
306 case GlobalValue::DefaultVisibility: return 0;
307 case GlobalValue::HiddenVisibility: return 1;
308 case GlobalValue::ProtectedVisibility: return 2;
312 // Emit top-level description of module, including target triple, inline asm,
313 // descriptors for global variables, and function prototype info.
314 static void WriteModuleInfo(const Module *M, const ValueEnumerator &VE,
315 BitstreamWriter &Stream) {
316 // Emit the list of dependent libraries for the Module.
317 for (Module::lib_iterator I = M->lib_begin(), E = M->lib_end(); I != E; ++I)
318 WriteStringRecord(bitc::MODULE_CODE_DEPLIB, *I, 0/*TODO*/, Stream);
320 // Emit various pieces of data attached to a module.
321 if (!M->getTargetTriple().empty())
322 WriteStringRecord(bitc::MODULE_CODE_TRIPLE, M->getTargetTriple(),
324 if (!M->getDataLayout().empty())
325 WriteStringRecord(bitc::MODULE_CODE_DATALAYOUT, M->getDataLayout(),
327 if (!M->getModuleInlineAsm().empty())
328 WriteStringRecord(bitc::MODULE_CODE_ASM, M->getModuleInlineAsm(),
331 // Emit information about sections and GC, computing how many there are. Also
332 // compute the maximum alignment value.
333 std::map<std::string, unsigned> SectionMap;
334 std::map<std::string, unsigned> GCMap;
335 unsigned MaxAlignment = 0;
336 unsigned MaxGlobalType = 0;
337 for (Module::const_global_iterator GV = M->global_begin(),E = M->global_end();
339 MaxAlignment = std::max(MaxAlignment, GV->getAlignment());
340 MaxGlobalType = std::max(MaxGlobalType, VE.getTypeID(GV->getType()));
342 if (!GV->hasSection()) continue;
343 // Give section names unique ID's.
344 unsigned &Entry = SectionMap[GV->getSection()];
345 if (Entry != 0) continue;
346 WriteStringRecord(bitc::MODULE_CODE_SECTIONNAME, GV->getSection(),
348 Entry = SectionMap.size();
350 for (Module::const_iterator F = M->begin(), E = M->end(); F != E; ++F) {
351 MaxAlignment = std::max(MaxAlignment, F->getAlignment());
352 if (F->hasSection()) {
353 // Give section names unique ID's.
354 unsigned &Entry = SectionMap[F->getSection()];
356 WriteStringRecord(bitc::MODULE_CODE_SECTIONNAME, F->getSection(),
358 Entry = SectionMap.size();
362 // Same for GC names.
363 unsigned &Entry = GCMap[F->getGC()];
365 WriteStringRecord(bitc::MODULE_CODE_GCNAME, F->getGC(),
367 Entry = GCMap.size();
372 // Emit abbrev for globals, now that we know # sections and max alignment.
373 unsigned SimpleGVarAbbrev = 0;
374 if (!M->global_empty()) {
375 // Add an abbrev for common globals with no visibility or thread localness.
376 BitCodeAbbrev *Abbv = new BitCodeAbbrev();
377 Abbv->Add(BitCodeAbbrevOp(bitc::MODULE_CODE_GLOBALVAR));
378 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
379 Log2_32_Ceil(MaxGlobalType+1)));
380 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // Constant.
381 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Initializer.
382 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 4)); // Linkage.
383 if (MaxAlignment == 0) // Alignment.
384 Abbv->Add(BitCodeAbbrevOp(0));
386 unsigned MaxEncAlignment = Log2_32(MaxAlignment)+1;
387 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
388 Log2_32_Ceil(MaxEncAlignment+1)));
390 if (SectionMap.empty()) // Section.
391 Abbv->Add(BitCodeAbbrevOp(0));
393 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
394 Log2_32_Ceil(SectionMap.size()+1)));
395 // Don't bother emitting vis + thread local.
396 SimpleGVarAbbrev = Stream.EmitAbbrev(Abbv);
399 // Emit the global variable information.
400 SmallVector<unsigned, 64> Vals;
401 for (Module::const_global_iterator GV = M->global_begin(),E = M->global_end();
403 unsigned AbbrevToUse = 0;
405 // GLOBALVAR: [type, isconst, initid,
406 // linkage, alignment, section, visibility, threadlocal]
407 Vals.push_back(VE.getTypeID(GV->getType()));
408 Vals.push_back(GV->isConstant());
409 Vals.push_back(GV->isDeclaration() ? 0 :
410 (VE.getValueID(GV->getInitializer()) + 1));
411 Vals.push_back(getEncodedLinkage(GV));
412 Vals.push_back(Log2_32(GV->getAlignment())+1);
413 Vals.push_back(GV->hasSection() ? SectionMap[GV->getSection()] : 0);
414 if (GV->isThreadLocal() ||
415 GV->getVisibility() != GlobalValue::DefaultVisibility) {
416 Vals.push_back(getEncodedVisibility(GV));
417 Vals.push_back(GV->isThreadLocal());
419 AbbrevToUse = SimpleGVarAbbrev;
422 Stream.EmitRecord(bitc::MODULE_CODE_GLOBALVAR, Vals, AbbrevToUse);
426 // Emit the function proto information.
427 for (Module::const_iterator F = M->begin(), E = M->end(); F != E; ++F) {
428 // FUNCTION: [type, callingconv, isproto, paramattr,
429 // linkage, alignment, section, visibility, gc]
430 Vals.push_back(VE.getTypeID(F->getType()));
431 Vals.push_back(F->getCallingConv());
432 Vals.push_back(F->isDeclaration());
433 Vals.push_back(getEncodedLinkage(F));
434 Vals.push_back(VE.getAttributeID(F->getAttributes()));
435 Vals.push_back(Log2_32(F->getAlignment())+1);
436 Vals.push_back(F->hasSection() ? SectionMap[F->getSection()] : 0);
437 Vals.push_back(getEncodedVisibility(F));
438 Vals.push_back(F->hasGC() ? GCMap[F->getGC()] : 0);
440 unsigned AbbrevToUse = 0;
441 Stream.EmitRecord(bitc::MODULE_CODE_FUNCTION, Vals, AbbrevToUse);
446 // Emit the alias information.
447 for (Module::const_alias_iterator AI = M->alias_begin(), E = M->alias_end();
449 Vals.push_back(VE.getTypeID(AI->getType()));
450 Vals.push_back(VE.getValueID(AI->getAliasee()));
451 Vals.push_back(getEncodedLinkage(AI));
452 Vals.push_back(getEncodedVisibility(AI));
453 unsigned AbbrevToUse = 0;
454 Stream.EmitRecord(bitc::MODULE_CODE_ALIAS, Vals, AbbrevToUse);
459 static uint64_t GetOptimizationFlags(const Value *V) {
462 if (const OverflowingBinaryOperator *OBO =
463 dyn_cast<OverflowingBinaryOperator>(V)) {
464 if (OBO->hasNoSignedWrap())
465 Flags |= 1 << bitc::OBO_NO_SIGNED_WRAP;
466 if (OBO->hasNoUnsignedWrap())
467 Flags |= 1 << bitc::OBO_NO_UNSIGNED_WRAP;
468 } else if (const SDivOperator *Div = dyn_cast<SDivOperator>(V)) {
470 Flags |= 1 << bitc::SDIV_EXACT;
476 static void WriteMDNode(const MDNode *N,
477 const ValueEnumerator &VE,
478 BitstreamWriter &Stream,
479 SmallVector<uint64_t, 64> &Record) {
480 for (unsigned i = 0, e = N->getNumElements(); i != e; ++i) {
481 if (N->getElement(i)) {
482 Record.push_back(VE.getTypeID(N->getElement(i)->getType()));
483 Record.push_back(VE.getValueID(N->getElement(i)));
485 Record.push_back(VE.getTypeID(Type::getVoidTy(N->getContext())));
489 Stream.EmitRecord(bitc::METADATA_NODE, Record, 0);
493 static void WriteModuleMetadata(const ValueEnumerator &VE,
494 BitstreamWriter &Stream) {
495 const ValueEnumerator::ValueList &Vals = VE.getMDValues();
496 bool StartedMetadataBlock = false;
497 unsigned MDSAbbrev = 0;
498 SmallVector<uint64_t, 64> Record;
499 for (unsigned i = 0, e = Vals.size(); i != e; ++i) {
501 if (const MDNode *N = dyn_cast<MDNode>(Vals[i].first)) {
502 if (!StartedMetadataBlock) {
503 Stream.EnterSubblock(bitc::METADATA_BLOCK_ID, 3);
504 StartedMetadataBlock = true;
506 WriteMDNode(N, VE, Stream, Record);
507 } else if (const MDString *MDS = dyn_cast<MDString>(Vals[i].first)) {
508 if (!StartedMetadataBlock) {
509 Stream.EnterSubblock(bitc::METADATA_BLOCK_ID, 3);
511 // Abbrev for METADATA_STRING.
512 BitCodeAbbrev *Abbv = new BitCodeAbbrev();
513 Abbv->Add(BitCodeAbbrevOp(bitc::METADATA_STRING));
514 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
515 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 8));
516 MDSAbbrev = Stream.EmitAbbrev(Abbv);
517 StartedMetadataBlock = true;
520 // Code: [strchar x N]
521 Record.append(MDS->begin(), MDS->end());
523 // Emit the finished record.
524 Stream.EmitRecord(bitc::METADATA_STRING, Record, MDSAbbrev);
526 } else if (const NamedMDNode *NMD = dyn_cast<NamedMDNode>(Vals[i].first)) {
527 if (!StartedMetadataBlock) {
528 Stream.EnterSubblock(bitc::METADATA_BLOCK_ID, 3);
529 StartedMetadataBlock = true;
533 std::string Str = NMD->getNameStr();
534 const char *StrBegin = Str.c_str();
535 for (unsigned i = 0, e = Str.length(); i != e; ++i)
536 Record.push_back(StrBegin[i]);
537 Stream.EmitRecord(bitc::METADATA_NAME, Record, 0/*TODO*/);
540 // Write named metadata elements.
541 for (unsigned i = 0, e = NMD->getNumElements(); i != e; ++i) {
542 if (NMD->getElement(i))
543 Record.push_back(VE.getValueID(NMD->getElement(i)));
547 Stream.EmitRecord(bitc::METADATA_NAMED_NODE, Record, 0);
552 if (StartedMetadataBlock)
556 static void WriteMetadataAttachment(const Function &F,
557 const ValueEnumerator &VE,
558 BitstreamWriter &Stream) {
559 bool StartedMetadataBlock = false;
560 SmallVector<uint64_t, 64> Record;
562 // Write metadata attachments
563 // METADATA_ATTACHMENT - [m x [value, [n x [id, mdnode]]]
564 MetadataContext &TheMetadata = F.getContext().getMetadata();
565 typedef SmallVector<std::pair<unsigned, TrackingVH<MDNode> >, 2> MDMapTy;
567 for (Function::const_iterator BB = F.begin(), E = F.end(); BB != E; ++BB)
568 for (BasicBlock::const_iterator I = BB->begin(), E = BB->end();
571 TheMetadata.getMDs(I, MDs);
572 bool RecordedInstruction = false;
573 for (MDMapTy::const_iterator PI = MDs.begin(), PE = MDs.end();
575 if (RecordedInstruction == false) {
576 Record.push_back(VE.getInstructionID(I));
577 RecordedInstruction = true;
579 Record.push_back(PI->first);
580 Record.push_back(VE.getValueID(PI->second));
582 if (!Record.empty()) {
583 if (!StartedMetadataBlock) {
584 Stream.EnterSubblock(bitc::METADATA_ATTACHMENT_ID, 3);
585 StartedMetadataBlock = true;
587 Stream.EmitRecord(bitc::METADATA_ATTACHMENT, Record, 0);
592 if (StartedMetadataBlock)
596 static void WriteModuleMetadataStore(const Module *M,
597 const ValueEnumerator &VE,
598 BitstreamWriter &Stream) {
600 bool StartedMetadataBlock = false;
601 SmallVector<uint64_t, 64> Record;
603 // Write metadata kinds
604 // METADATA_KIND - [n x [id, name]]
605 MetadataContext &TheMetadata = M->getContext().getMetadata();
606 SmallVector<std::pair<unsigned, StringRef>, 4> Names;
607 TheMetadata.getHandlerNames(Names);
608 for (SmallVector<std::pair<unsigned, StringRef>, 4>::iterator
610 E = Names.end(); I != E; ++I) {
611 Record.push_back(I->first);
612 StringRef KName = I->second;
613 for (unsigned i = 0, e = KName.size(); i != e; ++i)
614 Record.push_back(KName[i]);
615 if (!StartedMetadataBlock) {
616 Stream.EnterSubblock(bitc::METADATA_BLOCK_ID, 3);
617 StartedMetadataBlock = true;
619 Stream.EmitRecord(bitc::METADATA_KIND, Record, 0);
623 if (StartedMetadataBlock)
627 static void WriteConstants(unsigned FirstVal, unsigned LastVal,
628 const ValueEnumerator &VE,
629 BitstreamWriter &Stream, bool isGlobal) {
630 if (FirstVal == LastVal) return;
632 Stream.EnterSubblock(bitc::CONSTANTS_BLOCK_ID, 4);
634 unsigned AggregateAbbrev = 0;
635 unsigned String8Abbrev = 0;
636 unsigned CString7Abbrev = 0;
637 unsigned CString6Abbrev = 0;
638 // If this is a constant pool for the module, emit module-specific abbrevs.
640 // Abbrev for CST_CODE_AGGREGATE.
641 BitCodeAbbrev *Abbv = new BitCodeAbbrev();
642 Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_AGGREGATE));
643 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
644 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, Log2_32_Ceil(LastVal+1)));
645 AggregateAbbrev = Stream.EmitAbbrev(Abbv);
647 // Abbrev for CST_CODE_STRING.
648 Abbv = new BitCodeAbbrev();
649 Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_STRING));
650 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
651 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 8));
652 String8Abbrev = Stream.EmitAbbrev(Abbv);
653 // Abbrev for CST_CODE_CSTRING.
654 Abbv = new BitCodeAbbrev();
655 Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_CSTRING));
656 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
657 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 7));
658 CString7Abbrev = Stream.EmitAbbrev(Abbv);
659 // Abbrev for CST_CODE_CSTRING.
660 Abbv = new BitCodeAbbrev();
661 Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_CSTRING));
662 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
663 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Char6));
664 CString6Abbrev = Stream.EmitAbbrev(Abbv);
667 SmallVector<uint64_t, 64> Record;
669 const ValueEnumerator::ValueList &Vals = VE.getValues();
670 const Type *LastTy = 0;
671 for (unsigned i = FirstVal; i != LastVal; ++i) {
672 const Value *V = Vals[i].first;
673 // If we need to switch types, do so now.
674 if (V->getType() != LastTy) {
675 LastTy = V->getType();
676 Record.push_back(VE.getTypeID(LastTy));
677 Stream.EmitRecord(bitc::CST_CODE_SETTYPE, Record,
678 CONSTANTS_SETTYPE_ABBREV);
682 if (const InlineAsm *IA = dyn_cast<InlineAsm>(V)) {
683 Record.push_back(unsigned(IA->hasSideEffects()) |
684 unsigned(IA->isAlignStack()) << 1);
686 // Add the asm string.
687 const std::string &AsmStr = IA->getAsmString();
688 Record.push_back(AsmStr.size());
689 for (unsigned i = 0, e = AsmStr.size(); i != e; ++i)
690 Record.push_back(AsmStr[i]);
692 // Add the constraint string.
693 const std::string &ConstraintStr = IA->getConstraintString();
694 Record.push_back(ConstraintStr.size());
695 for (unsigned i = 0, e = ConstraintStr.size(); i != e; ++i)
696 Record.push_back(ConstraintStr[i]);
697 Stream.EmitRecord(bitc::CST_CODE_INLINEASM, Record);
701 const Constant *C = cast<Constant>(V);
703 unsigned AbbrevToUse = 0;
704 if (C->isNullValue()) {
705 Code = bitc::CST_CODE_NULL;
706 } else if (isa<UndefValue>(C)) {
707 Code = bitc::CST_CODE_UNDEF;
708 } else if (const ConstantInt *IV = dyn_cast<ConstantInt>(C)) {
709 if (IV->getBitWidth() <= 64) {
710 int64_t V = IV->getSExtValue();
712 Record.push_back(V << 1);
714 Record.push_back((-V << 1) | 1);
715 Code = bitc::CST_CODE_INTEGER;
716 AbbrevToUse = CONSTANTS_INTEGER_ABBREV;
717 } else { // Wide integers, > 64 bits in size.
718 // We have an arbitrary precision integer value to write whose
719 // bit width is > 64. However, in canonical unsigned integer
720 // format it is likely that the high bits are going to be zero.
721 // So, we only write the number of active words.
722 unsigned NWords = IV->getValue().getActiveWords();
723 const uint64_t *RawWords = IV->getValue().getRawData();
724 for (unsigned i = 0; i != NWords; ++i) {
725 int64_t V = RawWords[i];
727 Record.push_back(V << 1);
729 Record.push_back((-V << 1) | 1);
731 Code = bitc::CST_CODE_WIDE_INTEGER;
733 } else if (const ConstantFP *CFP = dyn_cast<ConstantFP>(C)) {
734 Code = bitc::CST_CODE_FLOAT;
735 const Type *Ty = CFP->getType();
736 if (Ty->isFloatTy() || Ty->isDoubleTy()) {
737 Record.push_back(CFP->getValueAPF().bitcastToAPInt().getZExtValue());
738 } else if (Ty->isX86_FP80Ty()) {
739 // api needed to prevent premature destruction
740 // bits are not in the same order as a normal i80 APInt, compensate.
741 APInt api = CFP->getValueAPF().bitcastToAPInt();
742 const uint64_t *p = api.getRawData();
743 Record.push_back((p[1] << 48) | (p[0] >> 16));
744 Record.push_back(p[0] & 0xffffLL);
745 } else if (Ty->isFP128Ty() || Ty->isPPC_FP128Ty()) {
746 APInt api = CFP->getValueAPF().bitcastToAPInt();
747 const uint64_t *p = api.getRawData();
748 Record.push_back(p[0]);
749 Record.push_back(p[1]);
751 assert (0 && "Unknown FP type!");
753 } else if (isa<ConstantArray>(C) && cast<ConstantArray>(C)->isString()) {
754 const ConstantArray *CA = cast<ConstantArray>(C);
755 // Emit constant strings specially.
756 unsigned NumOps = CA->getNumOperands();
757 // If this is a null-terminated string, use the denser CSTRING encoding.
758 if (CA->getOperand(NumOps-1)->isNullValue()) {
759 Code = bitc::CST_CODE_CSTRING;
760 --NumOps; // Don't encode the null, which isn't allowed by char6.
762 Code = bitc::CST_CODE_STRING;
763 AbbrevToUse = String8Abbrev;
765 bool isCStr7 = Code == bitc::CST_CODE_CSTRING;
766 bool isCStrChar6 = Code == bitc::CST_CODE_CSTRING;
767 for (unsigned i = 0; i != NumOps; ++i) {
768 unsigned char V = cast<ConstantInt>(CA->getOperand(i))->getZExtValue();
770 isCStr7 &= (V & 128) == 0;
772 isCStrChar6 = BitCodeAbbrevOp::isChar6(V);
776 AbbrevToUse = CString6Abbrev;
778 AbbrevToUse = CString7Abbrev;
779 } else if (isa<ConstantArray>(C) || isa<ConstantStruct>(V) ||
780 isa<ConstantVector>(V)) {
781 Code = bitc::CST_CODE_AGGREGATE;
782 for (unsigned i = 0, e = C->getNumOperands(); i != e; ++i)
783 Record.push_back(VE.getValueID(C->getOperand(i)));
784 AbbrevToUse = AggregateAbbrev;
785 } else if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(C)) {
786 switch (CE->getOpcode()) {
788 if (Instruction::isCast(CE->getOpcode())) {
789 Code = bitc::CST_CODE_CE_CAST;
790 Record.push_back(GetEncodedCastOpcode(CE->getOpcode()));
791 Record.push_back(VE.getTypeID(C->getOperand(0)->getType()));
792 Record.push_back(VE.getValueID(C->getOperand(0)));
793 AbbrevToUse = CONSTANTS_CE_CAST_Abbrev;
795 assert(CE->getNumOperands() == 2 && "Unknown constant expr!");
796 Code = bitc::CST_CODE_CE_BINOP;
797 Record.push_back(GetEncodedBinaryOpcode(CE->getOpcode()));
798 Record.push_back(VE.getValueID(C->getOperand(0)));
799 Record.push_back(VE.getValueID(C->getOperand(1)));
800 uint64_t Flags = GetOptimizationFlags(CE);
802 Record.push_back(Flags);
805 case Instruction::GetElementPtr:
806 Code = bitc::CST_CODE_CE_GEP;
807 if (cast<GEPOperator>(C)->isInBounds())
808 Code = bitc::CST_CODE_CE_INBOUNDS_GEP;
809 for (unsigned i = 0, e = CE->getNumOperands(); i != e; ++i) {
810 Record.push_back(VE.getTypeID(C->getOperand(i)->getType()));
811 Record.push_back(VE.getValueID(C->getOperand(i)));
814 case Instruction::Select:
815 Code = bitc::CST_CODE_CE_SELECT;
816 Record.push_back(VE.getValueID(C->getOperand(0)));
817 Record.push_back(VE.getValueID(C->getOperand(1)));
818 Record.push_back(VE.getValueID(C->getOperand(2)));
820 case Instruction::ExtractElement:
821 Code = bitc::CST_CODE_CE_EXTRACTELT;
822 Record.push_back(VE.getTypeID(C->getOperand(0)->getType()));
823 Record.push_back(VE.getValueID(C->getOperand(0)));
824 Record.push_back(VE.getValueID(C->getOperand(1)));
826 case Instruction::InsertElement:
827 Code = bitc::CST_CODE_CE_INSERTELT;
828 Record.push_back(VE.getValueID(C->getOperand(0)));
829 Record.push_back(VE.getValueID(C->getOperand(1)));
830 Record.push_back(VE.getValueID(C->getOperand(2)));
832 case Instruction::ShuffleVector:
833 // If the return type and argument types are the same, this is a
834 // standard shufflevector instruction. If the types are different,
835 // then the shuffle is widening or truncating the input vectors, and
836 // the argument type must also be encoded.
837 if (C->getType() == C->getOperand(0)->getType()) {
838 Code = bitc::CST_CODE_CE_SHUFFLEVEC;
840 Code = bitc::CST_CODE_CE_SHUFVEC_EX;
841 Record.push_back(VE.getTypeID(C->getOperand(0)->getType()));
843 Record.push_back(VE.getValueID(C->getOperand(0)));
844 Record.push_back(VE.getValueID(C->getOperand(1)));
845 Record.push_back(VE.getValueID(C->getOperand(2)));
847 case Instruction::ICmp:
848 case Instruction::FCmp:
849 Code = bitc::CST_CODE_CE_CMP;
850 Record.push_back(VE.getTypeID(C->getOperand(0)->getType()));
851 Record.push_back(VE.getValueID(C->getOperand(0)));
852 Record.push_back(VE.getValueID(C->getOperand(1)));
853 Record.push_back(CE->getPredicate());
857 llvm_unreachable("Unknown constant!");
859 Stream.EmitRecord(Code, Record, AbbrevToUse);
866 static void WriteModuleConstants(const ValueEnumerator &VE,
867 BitstreamWriter &Stream) {
868 const ValueEnumerator::ValueList &Vals = VE.getValues();
870 // Find the first constant to emit, which is the first non-globalvalue value.
871 // We know globalvalues have been emitted by WriteModuleInfo.
872 for (unsigned i = 0, e = Vals.size(); i != e; ++i) {
873 if (!isa<GlobalValue>(Vals[i].first)) {
874 WriteConstants(i, Vals.size(), VE, Stream, true);
880 /// PushValueAndType - The file has to encode both the value and type id for
881 /// many values, because we need to know what type to create for forward
882 /// references. However, most operands are not forward references, so this type
883 /// field is not needed.
885 /// This function adds V's value ID to Vals. If the value ID is higher than the
886 /// instruction ID, then it is a forward reference, and it also includes the
888 static bool PushValueAndType(const Value *V, unsigned InstID,
889 SmallVector<unsigned, 64> &Vals,
890 ValueEnumerator &VE) {
891 unsigned ValID = VE.getValueID(V);
892 Vals.push_back(ValID);
893 if (ValID >= InstID) {
894 Vals.push_back(VE.getTypeID(V->getType()));
900 /// WriteInstruction - Emit an instruction to the specified stream.
901 static void WriteInstruction(const Instruction &I, unsigned InstID,
902 ValueEnumerator &VE, BitstreamWriter &Stream,
903 SmallVector<unsigned, 64> &Vals) {
905 unsigned AbbrevToUse = 0;
906 VE.setInstructionID(&I);
907 switch (I.getOpcode()) {
909 if (Instruction::isCast(I.getOpcode())) {
910 Code = bitc::FUNC_CODE_INST_CAST;
911 if (!PushValueAndType(I.getOperand(0), InstID, Vals, VE))
912 AbbrevToUse = FUNCTION_INST_CAST_ABBREV;
913 Vals.push_back(VE.getTypeID(I.getType()));
914 Vals.push_back(GetEncodedCastOpcode(I.getOpcode()));
916 assert(isa<BinaryOperator>(I) && "Unknown instruction!");
917 Code = bitc::FUNC_CODE_INST_BINOP;
918 if (!PushValueAndType(I.getOperand(0), InstID, Vals, VE))
919 AbbrevToUse = FUNCTION_INST_BINOP_ABBREV;
920 Vals.push_back(VE.getValueID(I.getOperand(1)));
921 Vals.push_back(GetEncodedBinaryOpcode(I.getOpcode()));
922 uint64_t Flags = GetOptimizationFlags(&I);
924 if (AbbrevToUse == FUNCTION_INST_BINOP_ABBREV)
925 AbbrevToUse = FUNCTION_INST_BINOP_FLAGS_ABBREV;
926 Vals.push_back(Flags);
931 case Instruction::GetElementPtr:
932 Code = bitc::FUNC_CODE_INST_GEP;
933 if (cast<GEPOperator>(&I)->isInBounds())
934 Code = bitc::FUNC_CODE_INST_INBOUNDS_GEP;
935 for (unsigned i = 0, e = I.getNumOperands(); i != e; ++i)
936 PushValueAndType(I.getOperand(i), InstID, Vals, VE);
938 case Instruction::ExtractValue: {
939 Code = bitc::FUNC_CODE_INST_EXTRACTVAL;
940 PushValueAndType(I.getOperand(0), InstID, Vals, VE);
941 const ExtractValueInst *EVI = cast<ExtractValueInst>(&I);
942 for (const unsigned *i = EVI->idx_begin(), *e = EVI->idx_end(); i != e; ++i)
946 case Instruction::InsertValue: {
947 Code = bitc::FUNC_CODE_INST_INSERTVAL;
948 PushValueAndType(I.getOperand(0), InstID, Vals, VE);
949 PushValueAndType(I.getOperand(1), InstID, Vals, VE);
950 const InsertValueInst *IVI = cast<InsertValueInst>(&I);
951 for (const unsigned *i = IVI->idx_begin(), *e = IVI->idx_end(); i != e; ++i)
955 case Instruction::Select:
956 Code = bitc::FUNC_CODE_INST_VSELECT;
957 PushValueAndType(I.getOperand(1), InstID, Vals, VE);
958 Vals.push_back(VE.getValueID(I.getOperand(2)));
959 PushValueAndType(I.getOperand(0), InstID, Vals, VE);
961 case Instruction::ExtractElement:
962 Code = bitc::FUNC_CODE_INST_EXTRACTELT;
963 PushValueAndType(I.getOperand(0), InstID, Vals, VE);
964 Vals.push_back(VE.getValueID(I.getOperand(1)));
966 case Instruction::InsertElement:
967 Code = bitc::FUNC_CODE_INST_INSERTELT;
968 PushValueAndType(I.getOperand(0), InstID, Vals, VE);
969 Vals.push_back(VE.getValueID(I.getOperand(1)));
970 Vals.push_back(VE.getValueID(I.getOperand(2)));
972 case Instruction::ShuffleVector:
973 Code = bitc::FUNC_CODE_INST_SHUFFLEVEC;
974 PushValueAndType(I.getOperand(0), InstID, Vals, VE);
975 Vals.push_back(VE.getValueID(I.getOperand(1)));
976 Vals.push_back(VE.getValueID(I.getOperand(2)));
978 case Instruction::ICmp:
979 case Instruction::FCmp:
980 // compare returning Int1Ty or vector of Int1Ty
981 Code = bitc::FUNC_CODE_INST_CMP2;
982 PushValueAndType(I.getOperand(0), InstID, Vals, VE);
983 Vals.push_back(VE.getValueID(I.getOperand(1)));
984 Vals.push_back(cast<CmpInst>(I).getPredicate());
987 case Instruction::Ret:
989 Code = bitc::FUNC_CODE_INST_RET;
990 unsigned NumOperands = I.getNumOperands();
991 if (NumOperands == 0)
992 AbbrevToUse = FUNCTION_INST_RET_VOID_ABBREV;
993 else if (NumOperands == 1) {
994 if (!PushValueAndType(I.getOperand(0), InstID, Vals, VE))
995 AbbrevToUse = FUNCTION_INST_RET_VAL_ABBREV;
997 for (unsigned i = 0, e = NumOperands; i != e; ++i)
998 PushValueAndType(I.getOperand(i), InstID, Vals, VE);
1002 case Instruction::Br:
1004 Code = bitc::FUNC_CODE_INST_BR;
1005 BranchInst &II = cast<BranchInst>(I);
1006 Vals.push_back(VE.getValueID(II.getSuccessor(0)));
1007 if (II.isConditional()) {
1008 Vals.push_back(VE.getValueID(II.getSuccessor(1)));
1009 Vals.push_back(VE.getValueID(II.getCondition()));
1013 case Instruction::Switch:
1014 Code = bitc::FUNC_CODE_INST_SWITCH;
1015 Vals.push_back(VE.getTypeID(I.getOperand(0)->getType()));
1016 for (unsigned i = 0, e = I.getNumOperands(); i != e; ++i)
1017 Vals.push_back(VE.getValueID(I.getOperand(i)));
1019 case Instruction::IndirectBr:
1020 Code = bitc::FUNC_CODE_INST_INDIRECTBR;
1021 Vals.push_back(VE.getTypeID(I.getOperand(0)->getType()));
1022 for (unsigned i = 0, e = I.getNumOperands(); i != e; ++i)
1023 Vals.push_back(VE.getValueID(I.getOperand(i)));
1026 case Instruction::Invoke: {
1027 const InvokeInst *II = cast<InvokeInst>(&I);
1028 const Value *Callee(II->getCalledValue());
1029 const PointerType *PTy = cast<PointerType>(Callee->getType());
1030 const FunctionType *FTy = cast<FunctionType>(PTy->getElementType());
1031 Code = bitc::FUNC_CODE_INST_INVOKE;
1033 Vals.push_back(VE.getAttributeID(II->getAttributes()));
1034 Vals.push_back(II->getCallingConv());
1035 Vals.push_back(VE.getValueID(II->getNormalDest()));
1036 Vals.push_back(VE.getValueID(II->getUnwindDest()));
1037 PushValueAndType(Callee, InstID, Vals, VE);
1039 // Emit value #'s for the fixed parameters.
1040 for (unsigned i = 0, e = FTy->getNumParams(); i != e; ++i)
1041 Vals.push_back(VE.getValueID(I.getOperand(i+3))); // fixed param.
1043 // Emit type/value pairs for varargs params.
1044 if (FTy->isVarArg()) {
1045 for (unsigned i = 3+FTy->getNumParams(), e = I.getNumOperands();
1047 PushValueAndType(I.getOperand(i), InstID, Vals, VE); // vararg
1051 case Instruction::Unwind:
1052 Code = bitc::FUNC_CODE_INST_UNWIND;
1054 case Instruction::Unreachable:
1055 Code = bitc::FUNC_CODE_INST_UNREACHABLE;
1056 AbbrevToUse = FUNCTION_INST_UNREACHABLE_ABBREV;
1059 case Instruction::PHI:
1060 Code = bitc::FUNC_CODE_INST_PHI;
1061 Vals.push_back(VE.getTypeID(I.getType()));
1062 for (unsigned i = 0, e = I.getNumOperands(); i != e; ++i)
1063 Vals.push_back(VE.getValueID(I.getOperand(i)));
1066 case Instruction::Alloca:
1067 Code = bitc::FUNC_CODE_INST_ALLOCA;
1068 Vals.push_back(VE.getTypeID(I.getType()));
1069 Vals.push_back(VE.getValueID(I.getOperand(0))); // size.
1070 Vals.push_back(Log2_32(cast<AllocaInst>(I).getAlignment())+1);
1073 case Instruction::Load:
1074 Code = bitc::FUNC_CODE_INST_LOAD;
1075 if (!PushValueAndType(I.getOperand(0), InstID, Vals, VE)) // ptr
1076 AbbrevToUse = FUNCTION_INST_LOAD_ABBREV;
1078 Vals.push_back(Log2_32(cast<LoadInst>(I).getAlignment())+1);
1079 Vals.push_back(cast<LoadInst>(I).isVolatile());
1081 case Instruction::Store:
1082 Code = bitc::FUNC_CODE_INST_STORE2;
1083 PushValueAndType(I.getOperand(1), InstID, Vals, VE); // ptrty + ptr
1084 Vals.push_back(VE.getValueID(I.getOperand(0))); // val.
1085 Vals.push_back(Log2_32(cast<StoreInst>(I).getAlignment())+1);
1086 Vals.push_back(cast<StoreInst>(I).isVolatile());
1088 case Instruction::Call: {
1089 const PointerType *PTy = cast<PointerType>(I.getOperand(0)->getType());
1090 const FunctionType *FTy = cast<FunctionType>(PTy->getElementType());
1092 Code = bitc::FUNC_CODE_INST_CALL;
1094 const CallInst *CI = cast<CallInst>(&I);
1095 Vals.push_back(VE.getAttributeID(CI->getAttributes()));
1096 Vals.push_back((CI->getCallingConv() << 1) | unsigned(CI->isTailCall()));
1097 PushValueAndType(CI->getOperand(0), InstID, Vals, VE); // Callee
1099 // Emit value #'s for the fixed parameters.
1100 for (unsigned i = 0, e = FTy->getNumParams(); i != e; ++i)
1101 Vals.push_back(VE.getValueID(I.getOperand(i+1))); // fixed param.
1103 // Emit type/value pairs for varargs params.
1104 if (FTy->isVarArg()) {
1105 unsigned NumVarargs = I.getNumOperands()-1-FTy->getNumParams();
1106 for (unsigned i = I.getNumOperands()-NumVarargs, e = I.getNumOperands();
1108 PushValueAndType(I.getOperand(i), InstID, Vals, VE); // varargs
1112 case Instruction::VAArg:
1113 Code = bitc::FUNC_CODE_INST_VAARG;
1114 Vals.push_back(VE.getTypeID(I.getOperand(0)->getType())); // valistty
1115 Vals.push_back(VE.getValueID(I.getOperand(0))); // valist.
1116 Vals.push_back(VE.getTypeID(I.getType())); // restype.
1120 Stream.EmitRecord(Code, Vals, AbbrevToUse);
1124 // Emit names for globals/functions etc.
1125 static void WriteValueSymbolTable(const ValueSymbolTable &VST,
1126 const ValueEnumerator &VE,
1127 BitstreamWriter &Stream) {
1128 if (VST.empty()) return;
1129 Stream.EnterSubblock(bitc::VALUE_SYMTAB_BLOCK_ID, 4);
1131 // FIXME: Set up the abbrev, we know how many values there are!
1132 // FIXME: We know if the type names can use 7-bit ascii.
1133 SmallVector<unsigned, 64> NameVals;
1135 for (ValueSymbolTable::const_iterator SI = VST.begin(), SE = VST.end();
1138 const ValueName &Name = *SI;
1140 // Figure out the encoding to use for the name.
1142 bool isChar6 = true;
1143 for (const char *C = Name.getKeyData(), *E = C+Name.getKeyLength();
1146 isChar6 = BitCodeAbbrevOp::isChar6(*C);
1147 if ((unsigned char)*C & 128) {
1149 break; // don't bother scanning the rest.
1153 unsigned AbbrevToUse = VST_ENTRY_8_ABBREV;
1155 // VST_ENTRY: [valueid, namechar x N]
1156 // VST_BBENTRY: [bbid, namechar x N]
1158 if (isa<BasicBlock>(SI->getValue())) {
1159 Code = bitc::VST_CODE_BBENTRY;
1161 AbbrevToUse = VST_BBENTRY_6_ABBREV;
1163 Code = bitc::VST_CODE_ENTRY;
1165 AbbrevToUse = VST_ENTRY_6_ABBREV;
1167 AbbrevToUse = VST_ENTRY_7_ABBREV;
1170 NameVals.push_back(VE.getValueID(SI->getValue()));
1171 for (const char *P = Name.getKeyData(),
1172 *E = Name.getKeyData()+Name.getKeyLength(); P != E; ++P)
1173 NameVals.push_back((unsigned char)*P);
1175 // Emit the finished record.
1176 Stream.EmitRecord(Code, NameVals, AbbrevToUse);
1182 /// WriteFunction - Emit a function body to the module stream.
1183 static void WriteFunction(const Function &F, ValueEnumerator &VE,
1184 BitstreamWriter &Stream) {
1185 Stream.EnterSubblock(bitc::FUNCTION_BLOCK_ID, 4);
1186 VE.incorporateFunction(F);
1188 SmallVector<unsigned, 64> Vals;
1190 // Emit the number of basic blocks, so the reader can create them ahead of
1192 Vals.push_back(VE.getBasicBlocks().size());
1193 Stream.EmitRecord(bitc::FUNC_CODE_DECLAREBLOCKS, Vals);
1196 // If there are function-local constants, emit them now.
1197 unsigned CstStart, CstEnd;
1198 VE.getFunctionConstantRange(CstStart, CstEnd);
1199 WriteConstants(CstStart, CstEnd, VE, Stream, false);
1201 // Keep a running idea of what the instruction ID is.
1202 unsigned InstID = CstEnd;
1204 // Finally, emit all the instructions, in order.
1205 for (Function::const_iterator BB = F.begin(), E = F.end(); BB != E; ++BB)
1206 for (BasicBlock::const_iterator I = BB->begin(), E = BB->end();
1208 WriteInstruction(*I, InstID, VE, Stream, Vals);
1209 if (I->getType() != Type::getVoidTy(F.getContext()))
1213 // Emit names for all the instructions etc.
1214 WriteValueSymbolTable(F.getValueSymbolTable(), VE, Stream);
1216 WriteMetadataAttachment(F, VE, Stream);
1221 /// WriteTypeSymbolTable - Emit a block for the specified type symtab.
1222 static void WriteTypeSymbolTable(const TypeSymbolTable &TST,
1223 const ValueEnumerator &VE,
1224 BitstreamWriter &Stream) {
1225 if (TST.empty()) return;
1227 Stream.EnterSubblock(bitc::TYPE_SYMTAB_BLOCK_ID, 3);
1229 // 7-bit fixed width VST_CODE_ENTRY strings.
1230 BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1231 Abbv->Add(BitCodeAbbrevOp(bitc::VST_CODE_ENTRY));
1232 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
1233 Log2_32_Ceil(VE.getTypes().size()+1)));
1234 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1235 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 7));
1236 unsigned V7Abbrev = Stream.EmitAbbrev(Abbv);
1238 SmallVector<unsigned, 64> NameVals;
1240 for (TypeSymbolTable::const_iterator TI = TST.begin(), TE = TST.end();
1242 // TST_ENTRY: [typeid, namechar x N]
1243 NameVals.push_back(VE.getTypeID(TI->second));
1245 const std::string &Str = TI->first;
1247 for (unsigned i = 0, e = Str.size(); i != e; ++i) {
1248 NameVals.push_back((unsigned char)Str[i]);
1253 // Emit the finished record.
1254 Stream.EmitRecord(bitc::VST_CODE_ENTRY, NameVals, is7Bit ? V7Abbrev : 0);
1261 // Emit blockinfo, which defines the standard abbreviations etc.
1262 static void WriteBlockInfo(const ValueEnumerator &VE, BitstreamWriter &Stream) {
1263 // We only want to emit block info records for blocks that have multiple
1264 // instances: CONSTANTS_BLOCK, FUNCTION_BLOCK and VALUE_SYMTAB_BLOCK. Other
1265 // blocks can defined their abbrevs inline.
1266 Stream.EnterBlockInfoBlock(2);
1268 { // 8-bit fixed-width VST_ENTRY/VST_BBENTRY strings.
1269 BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1270 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3));
1271 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
1272 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1273 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 8));
1274 if (Stream.EmitBlockInfoAbbrev(bitc::VALUE_SYMTAB_BLOCK_ID,
1275 Abbv) != VST_ENTRY_8_ABBREV)
1276 llvm_unreachable("Unexpected abbrev ordering!");
1279 { // 7-bit fixed width VST_ENTRY strings.
1280 BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1281 Abbv->Add(BitCodeAbbrevOp(bitc::VST_CODE_ENTRY));
1282 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
1283 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1284 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 7));
1285 if (Stream.EmitBlockInfoAbbrev(bitc::VALUE_SYMTAB_BLOCK_ID,
1286 Abbv) != VST_ENTRY_7_ABBREV)
1287 llvm_unreachable("Unexpected abbrev ordering!");
1289 { // 6-bit char6 VST_ENTRY strings.
1290 BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1291 Abbv->Add(BitCodeAbbrevOp(bitc::VST_CODE_ENTRY));
1292 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
1293 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1294 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Char6));
1295 if (Stream.EmitBlockInfoAbbrev(bitc::VALUE_SYMTAB_BLOCK_ID,
1296 Abbv) != VST_ENTRY_6_ABBREV)
1297 llvm_unreachable("Unexpected abbrev ordering!");
1299 { // 6-bit char6 VST_BBENTRY strings.
1300 BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1301 Abbv->Add(BitCodeAbbrevOp(bitc::VST_CODE_BBENTRY));
1302 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
1303 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1304 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Char6));
1305 if (Stream.EmitBlockInfoAbbrev(bitc::VALUE_SYMTAB_BLOCK_ID,
1306 Abbv) != VST_BBENTRY_6_ABBREV)
1307 llvm_unreachable("Unexpected abbrev ordering!");
1312 { // SETTYPE abbrev for CONSTANTS_BLOCK.
1313 BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1314 Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_SETTYPE));
1315 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
1316 Log2_32_Ceil(VE.getTypes().size()+1)));
1317 if (Stream.EmitBlockInfoAbbrev(bitc::CONSTANTS_BLOCK_ID,
1318 Abbv) != CONSTANTS_SETTYPE_ABBREV)
1319 llvm_unreachable("Unexpected abbrev ordering!");
1322 { // INTEGER abbrev for CONSTANTS_BLOCK.
1323 BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1324 Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_INTEGER));
1325 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
1326 if (Stream.EmitBlockInfoAbbrev(bitc::CONSTANTS_BLOCK_ID,
1327 Abbv) != CONSTANTS_INTEGER_ABBREV)
1328 llvm_unreachable("Unexpected abbrev ordering!");
1331 { // CE_CAST abbrev for CONSTANTS_BLOCK.
1332 BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1333 Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_CE_CAST));
1334 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 4)); // cast opc
1335 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, // typeid
1336 Log2_32_Ceil(VE.getTypes().size()+1)));
1337 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8)); // value id
1339 if (Stream.EmitBlockInfoAbbrev(bitc::CONSTANTS_BLOCK_ID,
1340 Abbv) != CONSTANTS_CE_CAST_Abbrev)
1341 llvm_unreachable("Unexpected abbrev ordering!");
1343 { // NULL abbrev for CONSTANTS_BLOCK.
1344 BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1345 Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_NULL));
1346 if (Stream.EmitBlockInfoAbbrev(bitc::CONSTANTS_BLOCK_ID,
1347 Abbv) != CONSTANTS_NULL_Abbrev)
1348 llvm_unreachable("Unexpected abbrev ordering!");
1351 // FIXME: This should only use space for first class types!
1353 { // INST_LOAD abbrev for FUNCTION_BLOCK.
1354 BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1355 Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_LOAD));
1356 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Ptr
1357 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 4)); // Align
1358 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // volatile
1359 if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID,
1360 Abbv) != FUNCTION_INST_LOAD_ABBREV)
1361 llvm_unreachable("Unexpected abbrev ordering!");
1363 { // INST_BINOP abbrev for FUNCTION_BLOCK.
1364 BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1365 Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_BINOP));
1366 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // LHS
1367 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // RHS
1368 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 4)); // opc
1369 if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID,
1370 Abbv) != FUNCTION_INST_BINOP_ABBREV)
1371 llvm_unreachable("Unexpected abbrev ordering!");
1373 { // INST_BINOP_FLAGS abbrev for FUNCTION_BLOCK.
1374 BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1375 Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_BINOP));
1376 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // LHS
1377 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // RHS
1378 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 4)); // opc
1379 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 7)); // flags
1380 if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID,
1381 Abbv) != FUNCTION_INST_BINOP_FLAGS_ABBREV)
1382 llvm_unreachable("Unexpected abbrev ordering!");
1384 { // INST_CAST abbrev for FUNCTION_BLOCK.
1385 BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1386 Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_CAST));
1387 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // OpVal
1388 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, // dest ty
1389 Log2_32_Ceil(VE.getTypes().size()+1)));
1390 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 4)); // opc
1391 if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID,
1392 Abbv) != FUNCTION_INST_CAST_ABBREV)
1393 llvm_unreachable("Unexpected abbrev ordering!");
1396 { // INST_RET abbrev for FUNCTION_BLOCK.
1397 BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1398 Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_RET));
1399 if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID,
1400 Abbv) != FUNCTION_INST_RET_VOID_ABBREV)
1401 llvm_unreachable("Unexpected abbrev ordering!");
1403 { // INST_RET abbrev for FUNCTION_BLOCK.
1404 BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1405 Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_RET));
1406 Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // ValID
1407 if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID,
1408 Abbv) != FUNCTION_INST_RET_VAL_ABBREV)
1409 llvm_unreachable("Unexpected abbrev ordering!");
1411 { // INST_UNREACHABLE abbrev for FUNCTION_BLOCK.
1412 BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1413 Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_UNREACHABLE));
1414 if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID,
1415 Abbv) != FUNCTION_INST_UNREACHABLE_ABBREV)
1416 llvm_unreachable("Unexpected abbrev ordering!");
1423 /// WriteModule - Emit the specified module to the bitstream.
1424 static void WriteModule(const Module *M, BitstreamWriter &Stream) {
1425 Stream.EnterSubblock(bitc::MODULE_BLOCK_ID, 3);
1427 // Emit the version number if it is non-zero.
1429 SmallVector<unsigned, 1> Vals;
1430 Vals.push_back(CurVersion);
1431 Stream.EmitRecord(bitc::MODULE_CODE_VERSION, Vals);
1434 // Analyze the module, enumerating globals, functions, etc.
1435 ValueEnumerator VE(M);
1437 // Emit blockinfo, which defines the standard abbreviations etc.
1438 WriteBlockInfo(VE, Stream);
1440 // Emit information about parameter attributes.
1441 WriteAttributeTable(VE, Stream);
1443 // Emit information describing all of the types in the module.
1444 WriteTypeTable(VE, Stream);
1446 // Emit top-level description of module, including target triple, inline asm,
1447 // descriptors for global variables, and function prototype info.
1448 WriteModuleInfo(M, VE, Stream);
1451 WriteModuleConstants(VE, Stream);
1454 WriteModuleMetadata(VE, Stream);
1456 // Emit function bodies.
1457 for (Module::const_iterator I = M->begin(), E = M->end(); I != E; ++I)
1458 if (!I->isDeclaration())
1459 WriteFunction(*I, VE, Stream);
1462 WriteModuleMetadataStore(M, VE, Stream);
1464 // Emit the type symbol table information.
1465 WriteTypeSymbolTable(M->getTypeSymbolTable(), VE, Stream);
1467 // Emit names for globals/functions etc.
1468 WriteValueSymbolTable(M->getValueSymbolTable(), VE, Stream);
1473 /// EmitDarwinBCHeader - If generating a bc file on darwin, we have to emit a
1474 /// header and trailer to make it compatible with the system archiver. To do
1475 /// this we emit the following header, and then emit a trailer that pads the
1476 /// file out to be a multiple of 16 bytes.
1478 /// struct bc_header {
1479 /// uint32_t Magic; // 0x0B17C0DE
1480 /// uint32_t Version; // Version, currently always 0.
1481 /// uint32_t BitcodeOffset; // Offset to traditional bitcode file.
1482 /// uint32_t BitcodeSize; // Size of traditional bitcode file.
1483 /// uint32_t CPUType; // CPU specifier.
1484 /// ... potentially more later ...
1487 DarwinBCSizeFieldOffset = 3*4, // Offset to bitcode_size.
1488 DarwinBCHeaderSize = 5*4
1491 static void EmitDarwinBCHeader(BitstreamWriter &Stream,
1492 const std::string &TT) {
1493 unsigned CPUType = ~0U;
1495 // Match x86_64-*, i[3-9]86-*, powerpc-*, powerpc64-*. The CPUType is a
1496 // magic number from /usr/include/mach/machine.h. It is ok to reproduce the
1497 // specific constants here because they are implicitly part of the Darwin ABI.
1499 DARWIN_CPU_ARCH_ABI64 = 0x01000000,
1500 DARWIN_CPU_TYPE_X86 = 7,
1501 DARWIN_CPU_TYPE_POWERPC = 18
1504 if (TT.find("x86_64-") == 0)
1505 CPUType = DARWIN_CPU_TYPE_X86 | DARWIN_CPU_ARCH_ABI64;
1506 else if (TT.size() >= 5 && TT[0] == 'i' && TT[2] == '8' && TT[3] == '6' &&
1507 TT[4] == '-' && TT[1] - '3' < 6)
1508 CPUType = DARWIN_CPU_TYPE_X86;
1509 else if (TT.find("powerpc-") == 0)
1510 CPUType = DARWIN_CPU_TYPE_POWERPC;
1511 else if (TT.find("powerpc64-") == 0)
1512 CPUType = DARWIN_CPU_TYPE_POWERPC | DARWIN_CPU_ARCH_ABI64;
1514 // Traditional Bitcode starts after header.
1515 unsigned BCOffset = DarwinBCHeaderSize;
1517 Stream.Emit(0x0B17C0DE, 32);
1518 Stream.Emit(0 , 32); // Version.
1519 Stream.Emit(BCOffset , 32);
1520 Stream.Emit(0 , 32); // Filled in later.
1521 Stream.Emit(CPUType , 32);
1524 /// EmitDarwinBCTrailer - Emit the darwin epilog after the bitcode file and
1525 /// finalize the header.
1526 static void EmitDarwinBCTrailer(BitstreamWriter &Stream, unsigned BufferSize) {
1527 // Update the size field in the header.
1528 Stream.BackpatchWord(DarwinBCSizeFieldOffset, BufferSize-DarwinBCHeaderSize);
1530 // If the file is not a multiple of 16 bytes, insert dummy padding.
1531 while (BufferSize & 15) {
1538 /// WriteBitcodeToFile - Write the specified module to the specified output
1540 void llvm::WriteBitcodeToFile(const Module *M, raw_ostream &Out) {
1541 std::vector<unsigned char> Buffer;
1542 BitstreamWriter Stream(Buffer);
1544 Buffer.reserve(256*1024);
1546 WriteBitcodeToStream( M, Stream );
1548 // If writing to stdout, set binary mode.
1549 if (&llvm::outs() == &Out)
1550 sys::Program::ChangeStdoutToBinary();
1552 // Write the generated bitstream to "Out".
1553 Out.write((char*)&Buffer.front(), Buffer.size());
1555 // Make sure it hits disk now.
1559 /// WriteBitcodeToStream - Write the specified module to the specified output
1561 void llvm::WriteBitcodeToStream(const Module *M, BitstreamWriter &Stream) {
1562 // If this is darwin, emit a file header and trailer if needed.
1563 bool isDarwin = M->getTargetTriple().find("-darwin") != std::string::npos;
1565 EmitDarwinBCHeader(Stream, M->getTargetTriple());
1567 // Emit the file header.
1568 Stream.Emit((unsigned)'B', 8);
1569 Stream.Emit((unsigned)'C', 8);
1570 Stream.Emit(0x0, 4);
1571 Stream.Emit(0xC, 4);
1572 Stream.Emit(0xE, 4);
1573 Stream.Emit(0xD, 4);
1576 WriteModule(M, Stream);
1579 EmitDarwinBCTrailer(Stream, Stream.getBuffer().size());