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1 //===--- Bitcode/Writer/BitcodeWriter.cpp - Bitcode Writer ----------------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // Bitcode writer implementation.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "ReaderWriter_3_2.h"
15 #include "legacy_bitcode.h"
16 #include "ValueEnumerator.h"
17 #include "llvm/ADT/Triple.h"
18 #include "llvm/Bitcode/BitstreamWriter.h"
19 #include "llvm/Bitcode/LLVMBitCodes.h"
20 #include "llvm/IR/Constants.h"
21 #include "llvm/IR/DebugInfoMetadata.h"
22 #include "llvm/IR/DerivedTypes.h"
23 #include "llvm/IR/InlineAsm.h"
24 #include "llvm/IR/Instructions.h"
25 #include "llvm/IR/Module.h"
26 #include "llvm/IR/Operator.h"
27 #include "llvm/IR/UseListOrder.h"
28 #include "llvm/IR/ValueSymbolTable.h"
29 #include "llvm/Support/CommandLine.h"
30 #include "llvm/Support/ErrorHandling.h"
31 #include "llvm/Support/MathExtras.h"
32 #include "llvm/Support/Program.h"
33 #include "llvm/Support/raw_ostream.h"
34 #include <cctype>
35 #include <map>
36 using namespace llvm;
37 
38 /// These are manifest constants used by the bitcode writer. They do not need to
39 /// be kept in sync with the reader, but need to be consistent within this file.
40 enum {
41   // VALUE_SYMTAB_BLOCK abbrev id's.
42   VST_ENTRY_8_ABBREV = bitc::FIRST_APPLICATION_ABBREV,
43   VST_ENTRY_7_ABBREV,
44   VST_ENTRY_6_ABBREV,
45   VST_BBENTRY_6_ABBREV,
46 
47   // CONSTANTS_BLOCK abbrev id's.
48   CONSTANTS_SETTYPE_ABBREV = bitc::FIRST_APPLICATION_ABBREV,
49   CONSTANTS_INTEGER_ABBREV,
50   CONSTANTS_CE_CAST_Abbrev,
51   CONSTANTS_NULL_Abbrev,
52 
53   // FUNCTION_BLOCK abbrev id's.
54   FUNCTION_INST_LOAD_ABBREV = bitc::FIRST_APPLICATION_ABBREV,
55   FUNCTION_INST_BINOP_ABBREV,
56   FUNCTION_INST_BINOP_FLAGS_ABBREV,
57   FUNCTION_INST_CAST_ABBREV,
58   FUNCTION_INST_RET_VOID_ABBREV,
59   FUNCTION_INST_RET_VAL_ABBREV,
60   FUNCTION_INST_UNREACHABLE_ABBREV
61 };
62 
GetEncodedCastOpcode(unsigned Opcode)63 static unsigned GetEncodedCastOpcode(unsigned Opcode) {
64   switch (Opcode) {
65   default: llvm_unreachable("Unknown cast instruction!");
66   case Instruction::Trunc   : return bitc::CAST_TRUNC;
67   case Instruction::ZExt    : return bitc::CAST_ZEXT;
68   case Instruction::SExt    : return bitc::CAST_SEXT;
69   case Instruction::FPToUI  : return bitc::CAST_FPTOUI;
70   case Instruction::FPToSI  : return bitc::CAST_FPTOSI;
71   case Instruction::UIToFP  : return bitc::CAST_UITOFP;
72   case Instruction::SIToFP  : return bitc::CAST_SITOFP;
73   case Instruction::FPTrunc : return bitc::CAST_FPTRUNC;
74   case Instruction::FPExt   : return bitc::CAST_FPEXT;
75   case Instruction::PtrToInt: return bitc::CAST_PTRTOINT;
76   case Instruction::IntToPtr: return bitc::CAST_INTTOPTR;
77   case Instruction::BitCast : return bitc::CAST_BITCAST;
78   }
79 }
80 
GetEncodedBinaryOpcode(unsigned Opcode)81 static unsigned GetEncodedBinaryOpcode(unsigned Opcode) {
82   switch (Opcode) {
83   default: llvm_unreachable("Unknown binary instruction!");
84   case Instruction::Add:
85   case Instruction::FAdd: return bitc::BINOP_ADD;
86   case Instruction::Sub:
87   case Instruction::FSub: return bitc::BINOP_SUB;
88   case Instruction::Mul:
89   case Instruction::FMul: return bitc::BINOP_MUL;
90   case Instruction::UDiv: return bitc::BINOP_UDIV;
91   case Instruction::FDiv:
92   case Instruction::SDiv: return bitc::BINOP_SDIV;
93   case Instruction::URem: return bitc::BINOP_UREM;
94   case Instruction::FRem:
95   case Instruction::SRem: return bitc::BINOP_SREM;
96   case Instruction::Shl:  return bitc::BINOP_SHL;
97   case Instruction::LShr: return bitc::BINOP_LSHR;
98   case Instruction::AShr: return bitc::BINOP_ASHR;
99   case Instruction::And:  return bitc::BINOP_AND;
100   case Instruction::Or:   return bitc::BINOP_OR;
101   case Instruction::Xor:  return bitc::BINOP_XOR;
102   }
103 }
104 
GetEncodedRMWOperation(AtomicRMWInst::BinOp Op)105 static unsigned GetEncodedRMWOperation(AtomicRMWInst::BinOp Op) {
106   switch (Op) {
107   default: llvm_unreachable("Unknown RMW operation!");
108   case AtomicRMWInst::Xchg: return bitc::RMW_XCHG;
109   case AtomicRMWInst::Add: return bitc::RMW_ADD;
110   case AtomicRMWInst::Sub: return bitc::RMW_SUB;
111   case AtomicRMWInst::And: return bitc::RMW_AND;
112   case AtomicRMWInst::Nand: return bitc::RMW_NAND;
113   case AtomicRMWInst::Or: return bitc::RMW_OR;
114   case AtomicRMWInst::Xor: return bitc::RMW_XOR;
115   case AtomicRMWInst::Max: return bitc::RMW_MAX;
116   case AtomicRMWInst::Min: return bitc::RMW_MIN;
117   case AtomicRMWInst::UMax: return bitc::RMW_UMAX;
118   case AtomicRMWInst::UMin: return bitc::RMW_UMIN;
119   }
120 }
121 
GetEncodedOrdering(AtomicOrdering Ordering)122 static unsigned GetEncodedOrdering(AtomicOrdering Ordering) {
123   switch (Ordering) {
124   case NotAtomic: return bitc::ORDERING_NOTATOMIC;
125   case Unordered: return bitc::ORDERING_UNORDERED;
126   case Monotonic: return bitc::ORDERING_MONOTONIC;
127   case Acquire: return bitc::ORDERING_ACQUIRE;
128   case Release: return bitc::ORDERING_RELEASE;
129   case AcquireRelease: return bitc::ORDERING_ACQREL;
130   case SequentiallyConsistent: return bitc::ORDERING_SEQCST;
131   }
132   llvm_unreachable("Invalid ordering");
133 }
134 
GetEncodedSynchScope(SynchronizationScope SynchScope)135 static unsigned GetEncodedSynchScope(SynchronizationScope SynchScope) {
136   switch (SynchScope) {
137   case SingleThread: return bitc::SYNCHSCOPE_SINGLETHREAD;
138   case CrossThread: return bitc::SYNCHSCOPE_CROSSTHREAD;
139   }
140   llvm_unreachable("Invalid synch scope");
141 }
142 
WriteStringRecord(unsigned Code,StringRef Str,unsigned AbbrevToUse,BitstreamWriter & Stream)143 static void WriteStringRecord(unsigned Code, StringRef Str,
144                               unsigned AbbrevToUse, BitstreamWriter &Stream) {
145   SmallVector<unsigned, 64> Vals;
146 
147   // Code: [strchar x N]
148   for (unsigned i = 0, e = Str.size(); i != e; ++i) {
149     if (AbbrevToUse && !BitCodeAbbrevOp::isChar6(Str[i]))
150       AbbrevToUse = 0;
151     Vals.push_back(Str[i]);
152   }
153 
154   // Emit the finished record.
155   Stream.EmitRecord(Code, Vals, AbbrevToUse);
156 }
157 
158 // Emit information about parameter attributes.
WriteAttributeTable(const llvm_3_2::ValueEnumerator & VE,BitstreamWriter & Stream)159 static void WriteAttributeTable(const llvm_3_2::ValueEnumerator &VE,
160                                 BitstreamWriter &Stream) {
161   const std::vector<AttributeSet> &Attrs = VE.getAttributes();
162   if (Attrs.empty()) return;
163 
164   Stream.EnterSubblock(bitc::PARAMATTR_BLOCK_ID, 3);
165 
166   SmallVector<uint64_t, 64> Record;
167   for (unsigned i = 0, e = Attrs.size(); i != e; ++i) {
168     const AttributeSet &A = Attrs[i];
169     for (unsigned i = 0, e = A.getNumSlots(); i != e; ++i) {
170       Record.push_back(A.getSlotIndex(i));
171       Record.push_back(encodeLLVMAttributesForBitcode(A, A.getSlotIndex(i)));
172     }
173 
174     // This needs to use the 3.2 entry type
175     Stream.EmitRecord(bitc::PARAMATTR_CODE_ENTRY_OLD, Record);
176     Record.clear();
177   }
178 
179   Stream.ExitBlock();
180 }
181 
182 /// WriteTypeTable - Write out the type table for a module.
WriteTypeTable(const llvm_3_2::ValueEnumerator & VE,BitstreamWriter & Stream)183 static void WriteTypeTable(const llvm_3_2::ValueEnumerator &VE,
184                            BitstreamWriter &Stream) {
185   const llvm_3_2::ValueEnumerator::TypeList &TypeList = VE.getTypes();
186 
187   Stream.EnterSubblock(bitc::TYPE_BLOCK_ID_NEW, 4 /*count from # abbrevs */);
188   SmallVector<uint64_t, 64> TypeVals;
189 
190   uint64_t NumBits = Log2_32_Ceil(VE.getTypes().size()+1);
191 
192   // Abbrev for TYPE_CODE_POINTER.
193   BitCodeAbbrev *Abbv = new BitCodeAbbrev();
194   Abbv->Add(BitCodeAbbrevOp(bitc::TYPE_CODE_POINTER));
195   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, NumBits));
196   Abbv->Add(BitCodeAbbrevOp(0));  // Addrspace = 0
197   unsigned PtrAbbrev = Stream.EmitAbbrev(Abbv);
198 
199   // Abbrev for TYPE_CODE_FUNCTION.
200   Abbv = new BitCodeAbbrev();
201   Abbv->Add(BitCodeAbbrevOp(bitc::TYPE_CODE_FUNCTION));
202   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1));  // isvararg
203   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
204   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, NumBits));
205 
206   unsigned FunctionAbbrev = Stream.EmitAbbrev(Abbv);
207 
208   // Abbrev for TYPE_CODE_STRUCT_ANON.
209   Abbv = new BitCodeAbbrev();
210   Abbv->Add(BitCodeAbbrevOp(bitc::TYPE_CODE_STRUCT_ANON));
211   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1));  // ispacked
212   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
213   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, NumBits));
214 
215   unsigned StructAnonAbbrev = Stream.EmitAbbrev(Abbv);
216 
217   // Abbrev for TYPE_CODE_STRUCT_NAME.
218   Abbv = new BitCodeAbbrev();
219   Abbv->Add(BitCodeAbbrevOp(bitc::TYPE_CODE_STRUCT_NAME));
220   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
221   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Char6));
222   unsigned StructNameAbbrev = Stream.EmitAbbrev(Abbv);
223 
224   // Abbrev for TYPE_CODE_STRUCT_NAMED.
225   Abbv = new BitCodeAbbrev();
226   Abbv->Add(BitCodeAbbrevOp(bitc::TYPE_CODE_STRUCT_NAMED));
227   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1));  // ispacked
228   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
229   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, NumBits));
230 
231   unsigned StructNamedAbbrev = Stream.EmitAbbrev(Abbv);
232 
233   // Abbrev for TYPE_CODE_ARRAY.
234   Abbv = new BitCodeAbbrev();
235   Abbv->Add(BitCodeAbbrevOp(bitc::TYPE_CODE_ARRAY));
236   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));   // size
237   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, NumBits));
238 
239   unsigned ArrayAbbrev = Stream.EmitAbbrev(Abbv);
240 
241   // Emit an entry count so the reader can reserve space.
242   TypeVals.push_back(TypeList.size());
243   Stream.EmitRecord(bitc::TYPE_CODE_NUMENTRY, TypeVals);
244   TypeVals.clear();
245 
246   // Loop over all of the types, emitting each in turn.
247   for (unsigned i = 0, e = TypeList.size(); i != e; ++i) {
248     Type *T = TypeList[i];
249     int AbbrevToUse = 0;
250     unsigned Code = 0;
251 
252     switch (T->getTypeID()) {
253     default: llvm_unreachable("Unknown type!");
254     case Type::VoidTyID:      Code = bitc::TYPE_CODE_VOID;      break;
255     case Type::HalfTyID:      Code = bitc::TYPE_CODE_HALF;      break;
256     case Type::FloatTyID:     Code = bitc::TYPE_CODE_FLOAT;     break;
257     case Type::DoubleTyID:    Code = bitc::TYPE_CODE_DOUBLE;    break;
258     case Type::X86_FP80TyID:  Code = bitc::TYPE_CODE_X86_FP80;  break;
259     case Type::FP128TyID:     Code = bitc::TYPE_CODE_FP128;     break;
260     case Type::PPC_FP128TyID: Code = bitc::TYPE_CODE_PPC_FP128; break;
261     case Type::LabelTyID:     Code = bitc::TYPE_CODE_LABEL;     break;
262     case Type::MetadataTyID:  Code = bitc::TYPE_CODE_METADATA;  break;
263     case Type::X86_MMXTyID:   Code = bitc::TYPE_CODE_X86_MMX;   break;
264     case Type::IntegerTyID:
265       // INTEGER: [width]
266       Code = bitc::TYPE_CODE_INTEGER;
267       TypeVals.push_back(cast<IntegerType>(T)->getBitWidth());
268       break;
269     case Type::PointerTyID: {
270       PointerType *PTy = cast<PointerType>(T);
271       // POINTER: [pointee type, address space]
272       Code = bitc::TYPE_CODE_POINTER;
273       TypeVals.push_back(VE.getTypeID(PTy->getElementType()));
274       unsigned AddressSpace = PTy->getAddressSpace();
275       TypeVals.push_back(AddressSpace);
276       if (AddressSpace == 0) AbbrevToUse = PtrAbbrev;
277       break;
278     }
279     case Type::FunctionTyID: {
280       FunctionType *FT = cast<FunctionType>(T);
281       // FUNCTION: [isvararg, retty, paramty x N]
282       Code = bitc::TYPE_CODE_FUNCTION;
283       TypeVals.push_back(FT->isVarArg());
284       TypeVals.push_back(VE.getTypeID(FT->getReturnType()));
285       for (unsigned i = 0, e = FT->getNumParams(); i != e; ++i)
286         TypeVals.push_back(VE.getTypeID(FT->getParamType(i)));
287       AbbrevToUse = FunctionAbbrev;
288       break;
289     }
290     case Type::StructTyID: {
291       StructType *ST = cast<StructType>(T);
292       // STRUCT: [ispacked, eltty x N]
293       TypeVals.push_back(ST->isPacked());
294       // Output all of the element types.
295       for (StructType::element_iterator I = ST->element_begin(),
296            E = ST->element_end(); I != E; ++I)
297         TypeVals.push_back(VE.getTypeID(*I));
298 
299       if (ST->isLiteral()) {
300         Code = bitc::TYPE_CODE_STRUCT_ANON;
301         AbbrevToUse = StructAnonAbbrev;
302       } else {
303         if (ST->isOpaque()) {
304           Code = bitc::TYPE_CODE_OPAQUE;
305         } else {
306           Code = bitc::TYPE_CODE_STRUCT_NAMED;
307           AbbrevToUse = StructNamedAbbrev;
308         }
309 
310         // Emit the name if it is present.
311         if (!ST->getName().empty())
312           WriteStringRecord(bitc::TYPE_CODE_STRUCT_NAME, ST->getName(),
313                             StructNameAbbrev, Stream);
314       }
315       break;
316     }
317     case Type::ArrayTyID: {
318       ArrayType *AT = cast<ArrayType>(T);
319       // ARRAY: [numelts, eltty]
320       Code = bitc::TYPE_CODE_ARRAY;
321       TypeVals.push_back(AT->getNumElements());
322       TypeVals.push_back(VE.getTypeID(AT->getElementType()));
323       AbbrevToUse = ArrayAbbrev;
324       break;
325     }
326     case Type::VectorTyID: {
327       VectorType *VT = cast<VectorType>(T);
328       // VECTOR [numelts, eltty]
329       Code = bitc::TYPE_CODE_VECTOR;
330       TypeVals.push_back(VT->getNumElements());
331       TypeVals.push_back(VE.getTypeID(VT->getElementType()));
332       break;
333     }
334     }
335 
336     // Emit the finished record.
337     Stream.EmitRecord(Code, TypeVals, AbbrevToUse);
338     TypeVals.clear();
339   }
340 
341   Stream.ExitBlock();
342 }
343 
getEncodedLinkage(const GlobalValue & GV)344 static unsigned getEncodedLinkage(const GlobalValue &GV) {
345   switch (GV.getLinkage()) {
346   case GlobalValue::ExternalLinkage:
347     return 0;
348   case GlobalValue::WeakAnyLinkage:
349     return 1;
350   case GlobalValue::AppendingLinkage:
351     return 2;
352   case GlobalValue::InternalLinkage:
353     return 3;
354   case GlobalValue::LinkOnceAnyLinkage:
355     return 4;
356   case GlobalValue::ExternalWeakLinkage:
357     return 7;
358   case GlobalValue::CommonLinkage:
359     return 8;
360   case GlobalValue::PrivateLinkage:
361     return 9;
362   case GlobalValue::WeakODRLinkage:
363     return 10;
364   case GlobalValue::LinkOnceODRLinkage:
365     return 11;
366   case GlobalValue::AvailableExternallyLinkage:
367     return 12;
368   }
369   llvm_unreachable("Invalid linkage");
370 }
371 
getEncodedVisibility(const GlobalValue & GV)372 static unsigned getEncodedVisibility(const GlobalValue &GV) {
373   switch (GV.getVisibility()) {
374   case GlobalValue::DefaultVisibility:   return 0;
375   case GlobalValue::HiddenVisibility:    return 1;
376   case GlobalValue::ProtectedVisibility: return 2;
377   }
378   llvm_unreachable("Invalid visibility");
379 }
380 
getEncodedThreadLocalMode(const GlobalVariable & GV)381 static unsigned getEncodedThreadLocalMode(const GlobalVariable &GV) {
382   switch (GV.getThreadLocalMode()) {
383     case GlobalVariable::NotThreadLocal:         return 0;
384     case GlobalVariable::GeneralDynamicTLSModel: return 1;
385     case GlobalVariable::LocalDynamicTLSModel:   return 2;
386     case GlobalVariable::InitialExecTLSModel:    return 3;
387     case GlobalVariable::LocalExecTLSModel:      return 4;
388   }
389   llvm_unreachable("Invalid TLS model");
390 }
391 
392 // Emit top-level description of module, including target triple, inline asm,
393 // descriptors for global variables, and function prototype info.
WriteModuleInfo(const Module * M,const llvm_3_2::ValueEnumerator & VE,BitstreamWriter & Stream)394 static void WriteModuleInfo(const Module *M,
395                             const llvm_3_2::ValueEnumerator &VE,
396                             BitstreamWriter &Stream) {
397   // Emit various pieces of data attached to a module.
398   if (!M->getTargetTriple().empty())
399     WriteStringRecord(bitc::MODULE_CODE_TRIPLE, M->getTargetTriple(),
400                       0/*TODO*/, Stream);
401   const std::string &DL = M->getDataLayoutStr();
402   if (!DL.empty())
403     WriteStringRecord(bitc::MODULE_CODE_DATALAYOUT, DL, 0 /*TODO*/, Stream);
404   if (!M->getModuleInlineAsm().empty())
405     WriteStringRecord(bitc::MODULE_CODE_ASM, M->getModuleInlineAsm(),
406                       0/*TODO*/, Stream);
407 
408   // Emit information about sections and GC, computing how many there are. Also
409   // compute the maximum alignment value.
410   std::map<std::string, unsigned> SectionMap;
411   std::map<std::string, unsigned> GCMap;
412   unsigned MaxAlignment = 0;
413   unsigned MaxGlobalType = 0;
414   for (const GlobalValue &GV : M->globals()) {
415     MaxAlignment = std::max(MaxAlignment, GV.getAlignment());
416     MaxGlobalType = std::max(MaxGlobalType, VE.getTypeID(GV.getType()));
417     if (GV.hasSection()) {
418       // Give section names unique ID's.
419       unsigned &Entry = SectionMap[GV.getSection()];
420       if (!Entry) {
421         WriteStringRecord(bitc::MODULE_CODE_SECTIONNAME, GV.getSection(),
422                           0/*TODO*/, Stream);
423         Entry = SectionMap.size();
424       }
425     }
426   }
427   for (const Function &F : *M) {
428     MaxAlignment = std::max(MaxAlignment, F.getAlignment());
429     if (F.hasSection()) {
430       // Give section names unique ID's.
431       unsigned &Entry = SectionMap[F.getSection()];
432       if (!Entry) {
433         WriteStringRecord(bitc::MODULE_CODE_SECTIONNAME, F.getSection(),
434                           0/*TODO*/, Stream);
435         Entry = SectionMap.size();
436       }
437     }
438     if (F.hasGC()) {
439       // Same for GC names.
440       unsigned &Entry = GCMap[F.getGC()];
441       if (!Entry) {
442         WriteStringRecord(bitc::MODULE_CODE_GCNAME, F.getGC(),
443                           0/*TODO*/, Stream);
444         Entry = GCMap.size();
445       }
446     }
447   }
448 
449   // Emit abbrev for globals, now that we know # sections and max alignment.
450   unsigned SimpleGVarAbbrev = 0;
451   if (!M->global_empty()) {
452     // Add an abbrev for common globals with no visibility or thread localness.
453     BitCodeAbbrev *Abbv = new BitCodeAbbrev();
454     Abbv->Add(BitCodeAbbrevOp(bitc::MODULE_CODE_GLOBALVAR));
455     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
456                               Log2_32_Ceil(MaxGlobalType+1)));
457     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1));      // Constant.
458     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));        // Initializer.
459     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 4));      // Linkage.
460     if (MaxAlignment == 0)                                      // Alignment.
461       Abbv->Add(BitCodeAbbrevOp(0));
462     else {
463       unsigned MaxEncAlignment = Log2_32(MaxAlignment)+1;
464       Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
465                                Log2_32_Ceil(MaxEncAlignment+1)));
466     }
467     if (SectionMap.empty())                                    // Section.
468       Abbv->Add(BitCodeAbbrevOp(0));
469     else
470       Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
471                                Log2_32_Ceil(SectionMap.size()+1)));
472     // Don't bother emitting vis + thread local.
473     SimpleGVarAbbrev = Stream.EmitAbbrev(Abbv);
474   }
475 
476   // Emit the global variable information.
477   SmallVector<unsigned, 64> Vals;
478   for (const GlobalVariable &GV : M->globals()) {
479     unsigned AbbrevToUse = 0;
480 
481     // GLOBALVAR: [type, isconst, initid,
482     //             linkage, alignment, section, visibility, threadlocal,
483     //             unnamed_addr]
484     Vals.push_back(VE.getTypeID(GV.getType()));
485     Vals.push_back(GV.isConstant());
486     Vals.push_back(GV.isDeclaration() ? 0 :
487                    (VE.getValueID(GV.getInitializer()) + 1));
488     Vals.push_back(getEncodedLinkage(GV));
489     Vals.push_back(Log2_32(GV.getAlignment())+1);
490     Vals.push_back(GV.hasSection() ? SectionMap[GV.getSection()] : 0);
491     if (GV.isThreadLocal() ||
492         GV.getVisibility() != GlobalValue::DefaultVisibility ||
493         GV.hasUnnamedAddr() || GV.isExternallyInitialized()) {
494       Vals.push_back(getEncodedVisibility(GV));
495       Vals.push_back(getEncodedThreadLocalMode(GV));
496       Vals.push_back(GV.hasUnnamedAddr());
497       Vals.push_back(GV.isExternallyInitialized());
498     } else {
499       AbbrevToUse = SimpleGVarAbbrev;
500     }
501 
502     Stream.EmitRecord(bitc::MODULE_CODE_GLOBALVAR, Vals, AbbrevToUse);
503     Vals.clear();
504   }
505 
506   // Emit the function proto information.
507   for (const Function &F : *M) {
508     // FUNCTION:  [type, callingconv, isproto, linkage, paramattrs, alignment,
509     //             section, visibility, gc, unnamed_addr]
510     Vals.push_back(VE.getTypeID(F.getType()));
511     Vals.push_back(F.getCallingConv());
512     Vals.push_back(F.isDeclaration());
513     Vals.push_back(getEncodedLinkage(F));
514     Vals.push_back(VE.getAttributeID(F.getAttributes()));
515     Vals.push_back(Log2_32(F.getAlignment())+1);
516     Vals.push_back(F.hasSection() ? SectionMap[F.getSection()] : 0);
517     Vals.push_back(getEncodedVisibility(F));
518     Vals.push_back(F.hasGC() ? GCMap[F.getGC()] : 0);
519     Vals.push_back(F.hasUnnamedAddr());
520 
521     unsigned AbbrevToUse = 0;
522     Stream.EmitRecord(bitc::MODULE_CODE_FUNCTION, Vals, AbbrevToUse);
523     Vals.clear();
524   }
525 
526   // Emit the alias information.
527   for (const GlobalAlias &A : M->aliases()) {
528     // ALIAS: [alias type, aliasee val#, linkage, visibility]
529     Vals.push_back(VE.getTypeID(A.getType()));
530     Vals.push_back(VE.getValueID(A.getAliasee()));
531     Vals.push_back(getEncodedLinkage(A));
532     Vals.push_back(getEncodedVisibility(A));
533     unsigned AbbrevToUse = 0;
534     Stream.EmitRecord(bitc::MODULE_CODE_ALIAS, Vals, AbbrevToUse);
535     Vals.clear();
536   }
537 }
538 
GetOptimizationFlags(const Value * V)539 static uint64_t GetOptimizationFlags(const Value *V) {
540   uint64_t Flags = 0;
541 
542   if (const auto *OBO = dyn_cast<OverflowingBinaryOperator>(V)) {
543     if (OBO->hasNoSignedWrap())
544       Flags |= 1 << bitc::OBO_NO_SIGNED_WRAP;
545     if (OBO->hasNoUnsignedWrap())
546       Flags |= 1 << bitc::OBO_NO_UNSIGNED_WRAP;
547   } else if (const auto *PEO = dyn_cast<PossiblyExactOperator>(V)) {
548     if (PEO->isExact())
549       Flags |= 1 << bitc::PEO_EXACT;
550   } else if (const auto *FPMO = dyn_cast<FPMathOperator>(V)) {
551     // FIXME(srhines): We don't handle fast math in llvm-rs-cc today.
552     if (false) {
553       if (FPMO->hasUnsafeAlgebra())
554         Flags |= FastMathFlags::UnsafeAlgebra;
555       if (FPMO->hasNoNaNs())
556         Flags |= FastMathFlags::NoNaNs;
557       if (FPMO->hasNoInfs())
558         Flags |= FastMathFlags::NoInfs;
559       if (FPMO->hasNoSignedZeros())
560         Flags |= FastMathFlags::NoSignedZeros;
561       if (FPMO->hasAllowReciprocal())
562         Flags |= FastMathFlags::AllowReciprocal;
563     }
564   }
565 
566   return Flags;
567 }
568 
WriteValueAsMetadata(const ValueAsMetadata * MD,const llvm_3_2::ValueEnumerator & VE,BitstreamWriter & Stream,SmallVectorImpl<uint64_t> & Record)569 static void WriteValueAsMetadata(const ValueAsMetadata *MD,
570                                  const llvm_3_2::ValueEnumerator &VE,
571                                  BitstreamWriter &Stream,
572                                  SmallVectorImpl<uint64_t> &Record) {
573   // Mimic an MDNode with a value as one operand.
574   Value *V = MD->getValue();
575   Record.push_back(VE.getTypeID(V->getType()));
576   Record.push_back(VE.getValueID(V));
577   Stream.EmitRecord(bitc::METADATA_OLD_NODE, Record, 0);
578   Record.clear();
579 }
580 
WriteMDTuple(const MDTuple * N,const llvm_3_2::ValueEnumerator & VE,BitstreamWriter & Stream,SmallVectorImpl<uint64_t> & Record,unsigned Abbrev)581 static void WriteMDTuple(const MDTuple *N, const llvm_3_2::ValueEnumerator &VE,
582                          BitstreamWriter &Stream,
583                          SmallVectorImpl<uint64_t> &Record, unsigned Abbrev) {
584   for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i) {
585     Metadata *MD = N->getOperand(i);
586     assert(!(MD && isa<LocalAsMetadata>(MD)) &&
587            "Unexpected function-local metadata");
588     if (!MD) {
589       // TODO(srhines): I don't believe this case can exist for RS.
590       Record.push_back(VE.getTypeID(llvm::Type::getVoidTy(N->getContext())));
591       Record.push_back(0);
592     } else if (const auto *MDC = dyn_cast<ConstantAsMetadata>(MD)) {
593       Record.push_back(VE.getTypeID(MDC->getType()));
594       Record.push_back(VE.getValueID(MDC->getValue()));
595     } else {
596       Record.push_back(VE.getTypeID(
597           llvm::Type::getMetadataTy(N->getContext())));
598       Record.push_back(VE.getMetadataID(MD));
599     }
600   }
601   Stream.EmitRecord(bitc::METADATA_OLD_NODE, Record, Abbrev);
602   Record.clear();
603 }
604 
605 /*static void WriteMDLocation(const MDLocation *N, const llvm_3_2::ValueEnumerator &VE,
606                             BitstreamWriter &Stream,
607                             SmallVectorImpl<uint64_t> &Record,
608                             unsigned Abbrev) {
609   Record.push_back(N->isDistinct());
610   Record.push_back(N->getLine());
611   Record.push_back(N->getColumn());
612   Record.push_back(VE.getMetadataID(N->getScope()));
613   Record.push_back(VE.getMetadataOrNullID(N->getInlinedAt()));
614 
615   Stream.EmitRecord(bitc::METADATA_LOCATION, Record, Abbrev);
616   Record.clear();
617 }
618 
619 static void WriteGenericDebugNode(const GenericDebugNode *,
620                                   const llvm_3_2::ValueEnumerator &, BitstreamWriter &,
621                                   SmallVectorImpl<uint64_t> &, unsigned) {
622   llvm_unreachable("unimplemented");
623 }*/
624 
WriteModuleMetadata(const Module * M,const llvm_3_2::ValueEnumerator & VE,BitstreamWriter & Stream)625 static void WriteModuleMetadata(const Module *M,
626                                 const llvm_3_2::ValueEnumerator &VE,
627                                 BitstreamWriter &Stream) {
628   const auto &MDs = VE.getMDs();
629   if (MDs.empty() && M->named_metadata_empty())
630     return;
631 
632   // RenderScript files *ALWAYS* have metadata!
633   Stream.EnterSubblock(bitc::METADATA_BLOCK_ID, 3);
634 
635   unsigned MDSAbbrev = 0;
636   if (VE.hasMDString()) {
637     // Abbrev for METADATA_STRING.
638     BitCodeAbbrev *Abbv = new BitCodeAbbrev();
639     Abbv->Add(BitCodeAbbrevOp(bitc::METADATA_STRING));
640     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
641     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 8));
642     MDSAbbrev = Stream.EmitAbbrev(Abbv);
643   }
644 
645   unsigned MDLocationAbbrev = 0;
646   if (VE.hasMDLocation()) {
647     // TODO(srhines): Should be unreachable for RenderScript.
648     // Abbrev for METADATA_LOCATION.
649     //
650     // Assume the column is usually under 128, and always output the inlined-at
651     // location (it's never more expensive than building an array size 1).
652     BitCodeAbbrev *Abbv = new BitCodeAbbrev();
653     Abbv->Add(BitCodeAbbrevOp(bitc::METADATA_LOCATION));
654     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1));
655     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
656     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
657     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
658     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
659     MDLocationAbbrev = Stream.EmitAbbrev(Abbv);
660   }
661 
662   unsigned NameAbbrev = 0;
663   if (!M->named_metadata_empty()) {
664     // Abbrev for METADATA_NAME.
665     BitCodeAbbrev *Abbv = new BitCodeAbbrev();
666     Abbv->Add(BitCodeAbbrevOp(bitc::METADATA_NAME));
667     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
668     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 8));
669     NameAbbrev = Stream.EmitAbbrev(Abbv);
670   }
671 
672   unsigned MDTupleAbbrev = 0;
673   //unsigned GenericDebugNodeAbbrev = 0;
674   SmallVector<uint64_t, 64> Record;
675   for (const Metadata *MD : MDs) {
676     if (const MDNode *N = dyn_cast<MDNode>(MD)) {
677       switch (N->getMetadataID()) {
678       default:
679         llvm_unreachable("Invalid MDNode subclass");
680 #define HANDLE_SPECIALIZED_MDNODE_LEAF(CLASS)
681 #define HANDLE_MDNODE_LEAF(CLASS)                                              \
682   case Metadata::CLASS##Kind:                                                  \
683     Write##CLASS(cast<CLASS>(N), VE, Stream, Record, CLASS##Abbrev);           \
684     continue;
685 #include "llvm/IR/Metadata.def"
686       }
687     }
688     if (const auto *MDC = dyn_cast<ConstantAsMetadata>(MD)) {
689       WriteValueAsMetadata(MDC, VE, Stream, Record);
690       continue;
691     }
692     const MDString *MDS = cast<MDString>(MD);
693     // Code: [strchar x N]
694     Record.append(MDS->bytes_begin(), MDS->bytes_end());
695 
696     // Emit the finished record.
697     Stream.EmitRecord(bitc::METADATA_STRING, Record, MDSAbbrev);
698     Record.clear();
699   }
700 
701   // Write named metadata.
702   for (const NamedMDNode &NMD : M->named_metadata()) {
703     // Write name.
704     StringRef Str = NMD.getName();
705     Record.append(Str.bytes_begin(), Str.bytes_end());
706     Stream.EmitRecord(bitc::METADATA_NAME, Record, NameAbbrev);
707     Record.clear();
708 
709     // Write named metadata operands.
710     for (const MDNode *N : NMD.operands())
711       Record.push_back(VE.getMetadataID(N));
712     Stream.EmitRecord(bitc::METADATA_NAMED_NODE, Record, 0);
713     Record.clear();
714   }
715 
716   Stream.ExitBlock();
717 }
718 
WriteFunctionLocalMetadata(const Function & F,const llvm_3_2::ValueEnumerator & VE,BitstreamWriter & Stream)719 static void WriteFunctionLocalMetadata(const Function &F,
720                                        const llvm_3_2::ValueEnumerator &VE,
721                                        BitstreamWriter &Stream) {
722   bool StartedMetadataBlock = false;
723   SmallVector<uint64_t, 64> Record;
724   const SmallVectorImpl<const LocalAsMetadata *> &MDs =
725       VE.getFunctionLocalMDs();
726   for (unsigned i = 0, e = MDs.size(); i != e; ++i) {
727     assert(MDs[i] && "Expected valid function-local metadata");
728     if (!StartedMetadataBlock) {
729       Stream.EnterSubblock(bitc::METADATA_BLOCK_ID, 3);
730       StartedMetadataBlock = true;
731     }
732     WriteValueAsMetadata(MDs[i], VE, Stream, Record);
733   }
734 
735   if (StartedMetadataBlock)
736     Stream.ExitBlock();
737 }
738 
WriteMetadataAttachment(const Function & F,const llvm_3_2::ValueEnumerator & VE,BitstreamWriter & Stream)739 static void WriteMetadataAttachment(const Function &F,
740                                     const llvm_3_2::ValueEnumerator &VE,
741                                     BitstreamWriter &Stream) {
742   Stream.EnterSubblock(bitc::METADATA_ATTACHMENT_ID, 3);
743 
744   SmallVector<uint64_t, 64> Record;
745 
746   // Write metadata attachments
747   // METADATA_ATTACHMENT - [m x [value, [n x [id, mdnode]]]
748   SmallVector<std::pair<unsigned, MDNode *>, 4> MDs;
749 
750   for (Function::const_iterator BB = F.begin(), E = F.end(); BB != E; ++BB)
751     for (BasicBlock::const_iterator I = BB->begin(), E = BB->end();
752          I != E; ++I) {
753       MDs.clear();
754       I->getAllMetadataOtherThanDebugLoc(MDs);
755 
756       // If no metadata, ignore instruction.
757       if (MDs.empty()) continue;
758 
759       Record.push_back(VE.getInstructionID(I));
760 
761       for (unsigned i = 0, e = MDs.size(); i != e; ++i) {
762         Record.push_back(MDs[i].first);
763         Record.push_back(VE.getMetadataID(MDs[i].second));
764       }
765       Stream.EmitRecord(bitc::METADATA_ATTACHMENT, Record, 0);
766       Record.clear();
767     }
768 
769   Stream.ExitBlock();
770 }
771 
WriteModuleMetadataStore(const Module * M,BitstreamWriter & Stream)772 static void WriteModuleMetadataStore(const Module *M, BitstreamWriter &Stream) {
773   SmallVector<uint64_t, 64> Record;
774 
775   // Write metadata kinds
776   // METADATA_KIND - [n x [id, name]]
777   SmallVector<StringRef, 4> Names;
778   M->getMDKindNames(Names);
779 
780   if (Names.empty()) return;
781 
782   Stream.EnterSubblock(bitc::METADATA_BLOCK_ID, 3);
783 
784   for (unsigned MDKindID = 0, e = Names.size(); MDKindID != e; ++MDKindID) {
785     Record.push_back(MDKindID);
786     StringRef KName = Names[MDKindID];
787     Record.append(KName.begin(), KName.end());
788 
789     Stream.EmitRecord(bitc::METADATA_KIND, Record, 0);
790     Record.clear();
791   }
792 
793   Stream.ExitBlock();
794 }
795 
emitSignedInt64(SmallVectorImpl<uint64_t> & Vals,uint64_t V)796 static void emitSignedInt64(SmallVectorImpl<uint64_t> &Vals, uint64_t V) {
797   if ((int64_t)V >= 0)
798     Vals.push_back(V << 1);
799   else
800     Vals.push_back((-V << 1) | 1);
801 }
802 
WriteConstants(unsigned FirstVal,unsigned LastVal,const llvm_3_2::ValueEnumerator & VE,BitstreamWriter & Stream,bool isGlobal)803 static void WriteConstants(unsigned FirstVal, unsigned LastVal,
804                            const llvm_3_2::ValueEnumerator &VE,
805                            BitstreamWriter &Stream, bool isGlobal) {
806   if (FirstVal == LastVal) return;
807 
808   Stream.EnterSubblock(bitc::CONSTANTS_BLOCK_ID, 4);
809 
810   unsigned AggregateAbbrev = 0;
811   unsigned String8Abbrev = 0;
812   unsigned CString7Abbrev = 0;
813   unsigned CString6Abbrev = 0;
814   // If this is a constant pool for the module, emit module-specific abbrevs.
815   if (isGlobal) {
816     // Abbrev for CST_CODE_AGGREGATE.
817     BitCodeAbbrev *Abbv = new BitCodeAbbrev();
818     Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_AGGREGATE));
819     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
820     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, Log2_32_Ceil(LastVal+1)));
821     AggregateAbbrev = Stream.EmitAbbrev(Abbv);
822 
823     // Abbrev for CST_CODE_STRING.
824     Abbv = new BitCodeAbbrev();
825     Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_STRING));
826     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
827     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 8));
828     String8Abbrev = Stream.EmitAbbrev(Abbv);
829     // Abbrev for CST_CODE_CSTRING.
830     Abbv = new BitCodeAbbrev();
831     Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_CSTRING));
832     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
833     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 7));
834     CString7Abbrev = Stream.EmitAbbrev(Abbv);
835     // Abbrev for CST_CODE_CSTRING.
836     Abbv = new BitCodeAbbrev();
837     Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_CSTRING));
838     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
839     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Char6));
840     CString6Abbrev = Stream.EmitAbbrev(Abbv);
841   }
842 
843   SmallVector<uint64_t, 64> Record;
844 
845   const llvm_3_2::ValueEnumerator::ValueList &Vals = VE.getValues();
846   Type *LastTy = nullptr;
847   for (unsigned i = FirstVal; i != LastVal; ++i) {
848     const Value *V = Vals[i].first;
849     // If we need to switch types, do so now.
850     if (V->getType() != LastTy) {
851       LastTy = V->getType();
852       Record.push_back(VE.getTypeID(LastTy));
853       Stream.EmitRecord(bitc::CST_CODE_SETTYPE, Record,
854                         CONSTANTS_SETTYPE_ABBREV);
855       Record.clear();
856     }
857 
858     if (const InlineAsm *IA = dyn_cast<InlineAsm>(V)) {
859       Record.push_back(unsigned(IA->hasSideEffects()) |
860                        unsigned(IA->isAlignStack()) << 1 |
861                        unsigned(IA->getDialect()&1) << 2);
862 
863       // Add the asm string.
864       const std::string &AsmStr = IA->getAsmString();
865       Record.push_back(AsmStr.size());
866       for (unsigned i = 0, e = AsmStr.size(); i != e; ++i)
867         Record.push_back(AsmStr[i]);
868 
869       // Add the constraint string.
870       const std::string &ConstraintStr = IA->getConstraintString();
871       Record.push_back(ConstraintStr.size());
872       for (unsigned i = 0, e = ConstraintStr.size(); i != e; ++i)
873         Record.push_back(ConstraintStr[i]);
874       Stream.EmitRecord(bitc::CST_CODE_INLINEASM, Record);
875       Record.clear();
876       continue;
877     }
878     const Constant *C = cast<Constant>(V);
879     unsigned Code = -1U;
880     unsigned AbbrevToUse = 0;
881     if (C->isNullValue()) {
882       Code = bitc::CST_CODE_NULL;
883     } else if (isa<UndefValue>(C)) {
884       Code = bitc::CST_CODE_UNDEF;
885     } else if (const ConstantInt *IV = dyn_cast<ConstantInt>(C)) {
886       if (IV->getBitWidth() <= 64) {
887         uint64_t V = IV->getSExtValue();
888         emitSignedInt64(Record, V);
889         Code = bitc::CST_CODE_INTEGER;
890         AbbrevToUse = CONSTANTS_INTEGER_ABBREV;
891       } else {                             // Wide integers, > 64 bits in size.
892         // We have an arbitrary precision integer value to write whose
893         // bit width is > 64. However, in canonical unsigned integer
894         // format it is likely that the high bits are going to be zero.
895         // So, we only write the number of active words.
896         unsigned NWords = IV->getValue().getActiveWords();
897         const uint64_t *RawWords = IV->getValue().getRawData();
898         for (unsigned i = 0; i != NWords; ++i) {
899           emitSignedInt64(Record, RawWords[i]);
900         }
901         Code = bitc::CST_CODE_WIDE_INTEGER;
902       }
903     } else if (const ConstantFP *CFP = dyn_cast<ConstantFP>(C)) {
904       Code = bitc::CST_CODE_FLOAT;
905       Type *Ty = CFP->getType();
906       if (Ty->isHalfTy() || Ty->isFloatTy() || Ty->isDoubleTy()) {
907         Record.push_back(CFP->getValueAPF().bitcastToAPInt().getZExtValue());
908       } else if (Ty->isX86_FP80Ty()) {
909         // api needed to prevent premature destruction
910         // bits are not in the same order as a normal i80 APInt, compensate.
911         APInt api = CFP->getValueAPF().bitcastToAPInt();
912         const uint64_t *p = api.getRawData();
913         Record.push_back((p[1] << 48) | (p[0] >> 16));
914         Record.push_back(p[0] & 0xffffLL);
915       } else if (Ty->isFP128Ty() || Ty->isPPC_FP128Ty()) {
916         APInt api = CFP->getValueAPF().bitcastToAPInt();
917         const uint64_t *p = api.getRawData();
918         Record.push_back(p[0]);
919         Record.push_back(p[1]);
920       } else {
921         assert (0 && "Unknown FP type!");
922       }
923     } else if (isa<ConstantDataSequential>(C) &&
924                cast<ConstantDataSequential>(C)->isString()) {
925       const ConstantDataSequential *Str = cast<ConstantDataSequential>(C);
926       // Emit constant strings specially.
927       unsigned NumElts = Str->getNumElements();
928       // If this is a null-terminated string, use the denser CSTRING encoding.
929       if (Str->isCString()) {
930         Code = bitc::CST_CODE_CSTRING;
931         --NumElts;  // Don't encode the null, which isn't allowed by char6.
932       } else {
933         Code = bitc::CST_CODE_STRING;
934         AbbrevToUse = String8Abbrev;
935       }
936       bool isCStr7 = Code == bitc::CST_CODE_CSTRING;
937       bool isCStrChar6 = Code == bitc::CST_CODE_CSTRING;
938       for (unsigned i = 0; i != NumElts; ++i) {
939         unsigned char V = Str->getElementAsInteger(i);
940         Record.push_back(V);
941         isCStr7 &= (V & 128) == 0;
942         if (isCStrChar6)
943           isCStrChar6 = BitCodeAbbrevOp::isChar6(V);
944       }
945 
946       if (isCStrChar6)
947         AbbrevToUse = CString6Abbrev;
948       else if (isCStr7)
949         AbbrevToUse = CString7Abbrev;
950     } else if (const ConstantDataSequential *CDS =
951                   dyn_cast<ConstantDataSequential>(C)) {
952       Code = bitc::CST_CODE_DATA;
953       Type *EltTy = CDS->getType()->getElementType();
954       if (isa<IntegerType>(EltTy)) {
955         for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i)
956           Record.push_back(CDS->getElementAsInteger(i));
957       } else if (EltTy->isFloatTy()) {
958         for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
959           union { float F; uint32_t I; };
960           F = CDS->getElementAsFloat(i);
961           Record.push_back(I);
962         }
963       } else {
964         assert(EltTy->isDoubleTy() && "Unknown ConstantData element type");
965         for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
966           union { double F; uint64_t I; };
967           F = CDS->getElementAsDouble(i);
968           Record.push_back(I);
969         }
970       }
971     } else if (isa<ConstantArray>(C) || isa<ConstantStruct>(C) ||
972                isa<ConstantVector>(C)) {
973       Code = bitc::CST_CODE_AGGREGATE;
974       for (unsigned i = 0, e = C->getNumOperands(); i != e; ++i)
975         Record.push_back(VE.getValueID(C->getOperand(i)));
976       AbbrevToUse = AggregateAbbrev;
977     } else if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(C)) {
978       switch (CE->getOpcode()) {
979       default:
980         if (Instruction::isCast(CE->getOpcode())) {
981           Code = bitc::CST_CODE_CE_CAST;
982           Record.push_back(GetEncodedCastOpcode(CE->getOpcode()));
983           Record.push_back(VE.getTypeID(C->getOperand(0)->getType()));
984           Record.push_back(VE.getValueID(C->getOperand(0)));
985           AbbrevToUse = CONSTANTS_CE_CAST_Abbrev;
986         } else {
987           assert(CE->getNumOperands() == 2 && "Unknown constant expr!");
988           Code = bitc::CST_CODE_CE_BINOP;
989           Record.push_back(GetEncodedBinaryOpcode(CE->getOpcode()));
990           Record.push_back(VE.getValueID(C->getOperand(0)));
991           Record.push_back(VE.getValueID(C->getOperand(1)));
992           uint64_t Flags = GetOptimizationFlags(CE);
993           if (Flags != 0)
994             Record.push_back(Flags);
995         }
996         break;
997       case Instruction::GetElementPtr:
998         Code = bitc::CST_CODE_CE_GEP;
999         if (cast<GEPOperator>(C)->isInBounds())
1000           Code = bitc::CST_CODE_CE_INBOUNDS_GEP;
1001         for (unsigned i = 0, e = CE->getNumOperands(); i != e; ++i) {
1002           Record.push_back(VE.getTypeID(C->getOperand(i)->getType()));
1003           Record.push_back(VE.getValueID(C->getOperand(i)));
1004         }
1005         break;
1006       case Instruction::Select:
1007         Code = bitc::CST_CODE_CE_SELECT;
1008         Record.push_back(VE.getValueID(C->getOperand(0)));
1009         Record.push_back(VE.getValueID(C->getOperand(1)));
1010         Record.push_back(VE.getValueID(C->getOperand(2)));
1011         break;
1012       case Instruction::ExtractElement:
1013         Code = bitc::CST_CODE_CE_EXTRACTELT;
1014         Record.push_back(VE.getTypeID(C->getOperand(0)->getType()));
1015         Record.push_back(VE.getValueID(C->getOperand(0)));
1016         Record.push_back(VE.getValueID(C->getOperand(1)));
1017         break;
1018       case Instruction::InsertElement:
1019         Code = bitc::CST_CODE_CE_INSERTELT;
1020         Record.push_back(VE.getValueID(C->getOperand(0)));
1021         Record.push_back(VE.getValueID(C->getOperand(1)));
1022         Record.push_back(VE.getValueID(C->getOperand(2)));
1023         break;
1024       case Instruction::ShuffleVector:
1025         // If the return type and argument types are the same, this is a
1026         // standard shufflevector instruction.  If the types are different,
1027         // then the shuffle is widening or truncating the input vectors, and
1028         // the argument type must also be encoded.
1029         if (C->getType() == C->getOperand(0)->getType()) {
1030           Code = bitc::CST_CODE_CE_SHUFFLEVEC;
1031         } else {
1032           Code = bitc::CST_CODE_CE_SHUFVEC_EX;
1033           Record.push_back(VE.getTypeID(C->getOperand(0)->getType()));
1034         }
1035         Record.push_back(VE.getValueID(C->getOperand(0)));
1036         Record.push_back(VE.getValueID(C->getOperand(1)));
1037         Record.push_back(VE.getValueID(C->getOperand(2)));
1038         break;
1039       case Instruction::ICmp:
1040       case Instruction::FCmp:
1041         Code = bitc::CST_CODE_CE_CMP;
1042         Record.push_back(VE.getTypeID(C->getOperand(0)->getType()));
1043         Record.push_back(VE.getValueID(C->getOperand(0)));
1044         Record.push_back(VE.getValueID(C->getOperand(1)));
1045         Record.push_back(CE->getPredicate());
1046         break;
1047       }
1048     } else if (const BlockAddress *BA = dyn_cast<BlockAddress>(C)) {
1049       Code = bitc::CST_CODE_BLOCKADDRESS;
1050       Record.push_back(VE.getTypeID(BA->getFunction()->getType()));
1051       Record.push_back(VE.getValueID(BA->getFunction()));
1052       Record.push_back(VE.getGlobalBasicBlockID(BA->getBasicBlock()));
1053     } else {
1054 #ifndef NDEBUG
1055       C->dump();
1056 #endif
1057       llvm_unreachable("Unknown constant!");
1058     }
1059     Stream.EmitRecord(Code, Record, AbbrevToUse);
1060     Record.clear();
1061   }
1062 
1063   Stream.ExitBlock();
1064 }
1065 
WriteModuleConstants(const llvm_3_2::ValueEnumerator & VE,BitstreamWriter & Stream)1066 static void WriteModuleConstants(const llvm_3_2::ValueEnumerator &VE,
1067                                  BitstreamWriter &Stream) {
1068   const llvm_3_2::ValueEnumerator::ValueList &Vals = VE.getValues();
1069 
1070   // Find the first constant to emit, which is the first non-globalvalue value.
1071   // We know globalvalues have been emitted by WriteModuleInfo.
1072   for (unsigned i = 0, e = Vals.size(); i != e; ++i) {
1073     if (!isa<GlobalValue>(Vals[i].first)) {
1074       WriteConstants(i, Vals.size(), VE, Stream, true);
1075       return;
1076     }
1077   }
1078 }
1079 
1080 /// PushValueAndType - The file has to encode both the value and type id for
1081 /// many values, because we need to know what type to create for forward
1082 /// references.  However, most operands are not forward references, so this type
1083 /// field is not needed.
1084 ///
1085 /// This function adds V's value ID to Vals.  If the value ID is higher than the
1086 /// instruction ID, then it is a forward reference, and it also includes the
1087 /// type ID.
PushValueAndType(const Value * V,unsigned InstID,SmallVector<unsigned,64> & Vals,llvm_3_2::ValueEnumerator & VE)1088 static bool PushValueAndType(const Value *V, unsigned InstID,
1089                              SmallVector<unsigned, 64> &Vals,
1090                              llvm_3_2::ValueEnumerator &VE) {
1091   unsigned ValID = VE.getValueID(V);
1092   Vals.push_back(ValID);
1093   if (ValID >= InstID) {
1094     Vals.push_back(VE.getTypeID(V->getType()));
1095     return true;
1096   }
1097   return false;
1098 }
1099 
1100 /// WriteInstruction - Emit an instruction to the specified stream.
WriteInstruction(const Instruction & I,unsigned InstID,llvm_3_2::ValueEnumerator & VE,BitstreamWriter & Stream,SmallVector<unsigned,64> & Vals)1101 static void WriteInstruction(const Instruction &I, unsigned InstID,
1102                              llvm_3_2::ValueEnumerator &VE,
1103                              BitstreamWriter &Stream,
1104                              SmallVector<unsigned, 64> &Vals) {
1105   unsigned Code = 0;
1106   unsigned AbbrevToUse = 0;
1107   VE.setInstructionID(&I);
1108   switch (I.getOpcode()) {
1109   default:
1110     if (Instruction::isCast(I.getOpcode())) {
1111       Code = bitc::FUNC_CODE_INST_CAST;
1112       if (!PushValueAndType(I.getOperand(0), InstID, Vals, VE))
1113         AbbrevToUse = FUNCTION_INST_CAST_ABBREV;
1114       Vals.push_back(VE.getTypeID(I.getType()));
1115       Vals.push_back(GetEncodedCastOpcode(I.getOpcode()));
1116     } else {
1117       assert(isa<BinaryOperator>(I) && "Unknown instruction!");
1118       Code = bitc::FUNC_CODE_INST_BINOP;
1119       if (!PushValueAndType(I.getOperand(0), InstID, Vals, VE))
1120         AbbrevToUse = FUNCTION_INST_BINOP_ABBREV;
1121       Vals.push_back(VE.getValueID(I.getOperand(1)));
1122       Vals.push_back(GetEncodedBinaryOpcode(I.getOpcode()));
1123       uint64_t Flags = GetOptimizationFlags(&I);
1124       if (Flags != 0) {
1125         if (AbbrevToUse == FUNCTION_INST_BINOP_ABBREV)
1126           AbbrevToUse = FUNCTION_INST_BINOP_FLAGS_ABBREV;
1127         Vals.push_back(Flags);
1128       }
1129     }
1130     break;
1131 
1132   case Instruction::GetElementPtr:
1133     Code = bitc::FUNC_CODE_INST_GEP_OLD;
1134     if (cast<GEPOperator>(&I)->isInBounds())
1135       Code = bitc::FUNC_CODE_INST_INBOUNDS_GEP_OLD;
1136     for (unsigned i = 0, e = I.getNumOperands(); i != e; ++i)
1137       PushValueAndType(I.getOperand(i), InstID, Vals, VE);
1138     break;
1139   case Instruction::ExtractValue: {
1140     Code = bitc::FUNC_CODE_INST_EXTRACTVAL;
1141     PushValueAndType(I.getOperand(0), InstID, Vals, VE);
1142     const ExtractValueInst *EVI = cast<ExtractValueInst>(&I);
1143     for (const unsigned *i = EVI->idx_begin(), *e = EVI->idx_end(); i != e; ++i)
1144       Vals.push_back(*i);
1145     break;
1146   }
1147   case Instruction::InsertValue: {
1148     Code = bitc::FUNC_CODE_INST_INSERTVAL;
1149     PushValueAndType(I.getOperand(0), InstID, Vals, VE);
1150     PushValueAndType(I.getOperand(1), InstID, Vals, VE);
1151     const InsertValueInst *IVI = cast<InsertValueInst>(&I);
1152     for (const unsigned *i = IVI->idx_begin(), *e = IVI->idx_end(); i != e; ++i)
1153       Vals.push_back(*i);
1154     break;
1155   }
1156   case Instruction::Select:
1157     Code = bitc::FUNC_CODE_INST_VSELECT;
1158     PushValueAndType(I.getOperand(1), InstID, Vals, VE);
1159     Vals.push_back(VE.getValueID(I.getOperand(2)));
1160     PushValueAndType(I.getOperand(0), InstID, Vals, VE);
1161     break;
1162   case Instruction::ExtractElement:
1163     Code = bitc::FUNC_CODE_INST_EXTRACTELT;
1164     PushValueAndType(I.getOperand(0), InstID, Vals, VE);
1165     Vals.push_back(VE.getValueID(I.getOperand(1)));
1166     break;
1167   case Instruction::InsertElement:
1168     Code = bitc::FUNC_CODE_INST_INSERTELT;
1169     PushValueAndType(I.getOperand(0), InstID, Vals, VE);
1170     Vals.push_back(VE.getValueID(I.getOperand(1)));
1171     Vals.push_back(VE.getValueID(I.getOperand(2)));
1172     break;
1173   case Instruction::ShuffleVector:
1174     Code = bitc::FUNC_CODE_INST_SHUFFLEVEC;
1175     PushValueAndType(I.getOperand(0), InstID, Vals, VE);
1176     Vals.push_back(VE.getValueID(I.getOperand(1)));
1177     Vals.push_back(VE.getValueID(I.getOperand(2)));
1178     break;
1179   case Instruction::ICmp:
1180   case Instruction::FCmp:
1181     // compare returning Int1Ty or vector of Int1Ty
1182     Code = bitc::FUNC_CODE_INST_CMP2;
1183     PushValueAndType(I.getOperand(0), InstID, Vals, VE);
1184     Vals.push_back(VE.getValueID(I.getOperand(1)));
1185     Vals.push_back(cast<CmpInst>(I).getPredicate());
1186     break;
1187 
1188   case Instruction::Ret:
1189     {
1190       Code = bitc::FUNC_CODE_INST_RET;
1191       unsigned NumOperands = I.getNumOperands();
1192       if (NumOperands == 0)
1193         AbbrevToUse = FUNCTION_INST_RET_VOID_ABBREV;
1194       else if (NumOperands == 1) {
1195         if (!PushValueAndType(I.getOperand(0), InstID, Vals, VE))
1196           AbbrevToUse = FUNCTION_INST_RET_VAL_ABBREV;
1197       } else {
1198         for (unsigned i = 0, e = NumOperands; i != e; ++i)
1199           PushValueAndType(I.getOperand(i), InstID, Vals, VE);
1200       }
1201     }
1202     break;
1203   case Instruction::Br:
1204     {
1205       Code = bitc::FUNC_CODE_INST_BR;
1206       const BranchInst &II = cast<BranchInst>(I);
1207       Vals.push_back(VE.getValueID(II.getSuccessor(0)));
1208       if (II.isConditional()) {
1209         Vals.push_back(VE.getValueID(II.getSuccessor(1)));
1210         Vals.push_back(VE.getValueID(II.getCondition()));
1211       }
1212     }
1213     break;
1214   case Instruction::Switch:
1215     {
1216       Code = bitc::FUNC_CODE_INST_SWITCH;
1217       const SwitchInst &SI = cast<SwitchInst>(I);
1218       Vals.push_back(VE.getTypeID(SI.getCondition()->getType()));
1219       Vals.push_back(VE.getValueID(SI.getCondition()));
1220       Vals.push_back(VE.getValueID(SI.getDefaultDest()));
1221       for (SwitchInst::ConstCaseIt i = SI.case_begin(), e = SI.case_end();
1222            i != e; ++i) {
1223         Vals.push_back(VE.getValueID(i.getCaseValue()));
1224         Vals.push_back(VE.getValueID(i.getCaseSuccessor()));
1225       }
1226     }
1227     break;
1228   case Instruction::IndirectBr:
1229     Code = bitc::FUNC_CODE_INST_INDIRECTBR;
1230     Vals.push_back(VE.getTypeID(I.getOperand(0)->getType()));
1231     for (unsigned i = 0, e = I.getNumOperands(); i != e; ++i)
1232       Vals.push_back(VE.getValueID(I.getOperand(i)));
1233     break;
1234 
1235   case Instruction::Invoke: {
1236     const InvokeInst *II = cast<InvokeInst>(&I);
1237     const Value *Callee(II->getCalledValue());
1238     PointerType *PTy = cast<PointerType>(Callee->getType());
1239     FunctionType *FTy = cast<FunctionType>(PTy->getElementType());
1240     Code = bitc::FUNC_CODE_INST_INVOKE;
1241 
1242     Vals.push_back(VE.getAttributeID(II->getAttributes()));
1243     Vals.push_back(II->getCallingConv());
1244     Vals.push_back(VE.getValueID(II->getNormalDest()));
1245     Vals.push_back(VE.getValueID(II->getUnwindDest()));
1246     PushValueAndType(Callee, InstID, Vals, VE);
1247 
1248     // Emit value #'s for the fixed parameters.
1249     for (unsigned i = 0, e = FTy->getNumParams(); i != e; ++i)
1250       Vals.push_back(VE.getValueID(I.getOperand(i)));  // fixed param.
1251 
1252     // Emit type/value pairs for varargs params.
1253     if (FTy->isVarArg()) {
1254       for (unsigned i = FTy->getNumParams(), e = I.getNumOperands()-3;
1255            i != e; ++i)
1256         PushValueAndType(I.getOperand(i), InstID, Vals, VE); // vararg
1257     }
1258     break;
1259   }
1260   case Instruction::Resume:
1261     Code = bitc::FUNC_CODE_INST_RESUME;
1262     PushValueAndType(I.getOperand(0), InstID, Vals, VE);
1263     break;
1264   case Instruction::Unreachable:
1265     Code = bitc::FUNC_CODE_INST_UNREACHABLE;
1266     AbbrevToUse = FUNCTION_INST_UNREACHABLE_ABBREV;
1267     break;
1268 
1269   case Instruction::PHI: {
1270     const PHINode &PN = cast<PHINode>(I);
1271     Code = bitc::FUNC_CODE_INST_PHI;
1272     Vals.push_back(VE.getTypeID(PN.getType()));
1273     for (unsigned i = 0, e = PN.getNumIncomingValues(); i != e; ++i) {
1274       Vals.push_back(VE.getValueID(PN.getIncomingValue(i)));
1275       Vals.push_back(VE.getValueID(PN.getIncomingBlock(i)));
1276     }
1277     break;
1278   }
1279 
1280   case Instruction::LandingPad: {
1281     const LandingPadInst &LP = cast<LandingPadInst>(I);
1282     Code = bitc::FUNC_CODE_INST_LANDINGPAD;
1283     Vals.push_back(VE.getTypeID(LP.getType()));
1284     PushValueAndType(LP.getPersonalityFn(), InstID, Vals, VE);
1285     Vals.push_back(LP.isCleanup());
1286     Vals.push_back(LP.getNumClauses());
1287     for (unsigned I = 0, E = LP.getNumClauses(); I != E; ++I) {
1288       if (LP.isCatch(I))
1289         Vals.push_back(LandingPadInst::Catch);
1290       else
1291         Vals.push_back(LandingPadInst::Filter);
1292       PushValueAndType(LP.getClause(I), InstID, Vals, VE);
1293     }
1294     break;
1295   }
1296 
1297   case Instruction::Alloca: {
1298     Code = bitc::FUNC_CODE_INST_ALLOCA;
1299     Vals.push_back(VE.getTypeID(I.getType()));
1300     Vals.push_back(VE.getTypeID(I.getOperand(0)->getType()));
1301     Vals.push_back(VE.getValueID(I.getOperand(0))); // size.
1302     Vals.push_back(Log2_32(cast<AllocaInst>(I).getAlignment())+1);
1303     break;
1304   }
1305 
1306   case Instruction::Load:
1307     if (cast<LoadInst>(I).isAtomic()) {
1308       Code = bitc::FUNC_CODE_INST_LOADATOMIC;
1309       PushValueAndType(I.getOperand(0), InstID, Vals, VE);
1310     } else {
1311       Code = bitc::FUNC_CODE_INST_LOAD;
1312       if (!PushValueAndType(I.getOperand(0), InstID, Vals, VE))  // ptr
1313         AbbrevToUse = FUNCTION_INST_LOAD_ABBREV;
1314     }
1315     Vals.push_back(Log2_32(cast<LoadInst>(I).getAlignment())+1);
1316     Vals.push_back(cast<LoadInst>(I).isVolatile());
1317     if (cast<LoadInst>(I).isAtomic()) {
1318       Vals.push_back(GetEncodedOrdering(cast<LoadInst>(I).getOrdering()));
1319       Vals.push_back(GetEncodedSynchScope(cast<LoadInst>(I).getSynchScope()));
1320     }
1321     break;
1322   case Instruction::Store:
1323     if (cast<StoreInst>(I).isAtomic())
1324       Code = bitc::FUNC_CODE_INST_STOREATOMIC;
1325     else
1326       Code = bitc::FUNC_CODE_INST_STORE;
1327     PushValueAndType(I.getOperand(1), InstID, Vals, VE);  // ptrty + ptr
1328     Vals.push_back(VE.getValueID(I.getOperand(0)));       // val.
1329     Vals.push_back(Log2_32(cast<StoreInst>(I).getAlignment())+1);
1330     Vals.push_back(cast<StoreInst>(I).isVolatile());
1331     if (cast<StoreInst>(I).isAtomic()) {
1332       Vals.push_back(GetEncodedOrdering(cast<StoreInst>(I).getOrdering()));
1333       Vals.push_back(GetEncodedSynchScope(cast<StoreInst>(I).getSynchScope()));
1334     }
1335     break;
1336   case Instruction::AtomicCmpXchg:
1337     Code = bitc::FUNC_CODE_INST_CMPXCHG;
1338     PushValueAndType(I.getOperand(0), InstID, Vals, VE);  // ptrty + ptr
1339     Vals.push_back(VE.getValueID(I.getOperand(1)));       // cmp.
1340     Vals.push_back(VE.getValueID(I.getOperand(2)));       // newval.
1341     Vals.push_back(cast<AtomicCmpXchgInst>(I).isVolatile());
1342     Vals.push_back(GetEncodedOrdering(
1343                      cast<AtomicCmpXchgInst>(I).getSuccessOrdering()));
1344     Vals.push_back(GetEncodedSynchScope(
1345                      cast<AtomicCmpXchgInst>(I).getSynchScope()));
1346     break;
1347   case Instruction::AtomicRMW:
1348     Code = bitc::FUNC_CODE_INST_ATOMICRMW;
1349     PushValueAndType(I.getOperand(0), InstID, Vals, VE);  // ptrty + ptr
1350     Vals.push_back(VE.getValueID(I.getOperand(1)));       // val.
1351     Vals.push_back(GetEncodedRMWOperation(
1352                      cast<AtomicRMWInst>(I).getOperation()));
1353     Vals.push_back(cast<AtomicRMWInst>(I).isVolatile());
1354     Vals.push_back(GetEncodedOrdering(cast<AtomicRMWInst>(I).getOrdering()));
1355     Vals.push_back(GetEncodedSynchScope(
1356                      cast<AtomicRMWInst>(I).getSynchScope()));
1357     break;
1358   case Instruction::Fence:
1359     Code = bitc::FUNC_CODE_INST_FENCE;
1360     Vals.push_back(GetEncodedOrdering(cast<FenceInst>(I).getOrdering()));
1361     Vals.push_back(GetEncodedSynchScope(cast<FenceInst>(I).getSynchScope()));
1362     break;
1363   case Instruction::Call: {
1364     const CallInst &CI = cast<CallInst>(I);
1365     PointerType *PTy = cast<PointerType>(CI.getCalledValue()->getType());
1366     FunctionType *FTy = cast<FunctionType>(PTy->getElementType());
1367 
1368     Code = bitc::FUNC_CODE_INST_CALL;
1369 
1370     Vals.push_back(VE.getAttributeID(CI.getAttributes()));
1371     Vals.push_back((CI.getCallingConv() << 1) | unsigned(CI.isTailCall()));
1372     PushValueAndType(CI.getCalledValue(), InstID, Vals, VE);  // Callee
1373 
1374     // Emit value #'s for the fixed parameters.
1375     for (unsigned i = 0, e = FTy->getNumParams(); i != e; ++i)
1376       Vals.push_back(VE.getValueID(CI.getArgOperand(i)));  // fixed param.
1377 
1378     // Emit type/value pairs for varargs params.
1379     if (FTy->isVarArg()) {
1380       for (unsigned i = FTy->getNumParams(), e = CI.getNumArgOperands();
1381            i != e; ++i)
1382         PushValueAndType(CI.getArgOperand(i), InstID, Vals, VE);  // varargs
1383     }
1384     break;
1385   }
1386   case Instruction::VAArg:
1387     Code = bitc::FUNC_CODE_INST_VAARG;
1388     Vals.push_back(VE.getTypeID(I.getOperand(0)->getType()));   // valistty
1389     Vals.push_back(VE.getValueID(I.getOperand(0))); // valist.
1390     Vals.push_back(VE.getTypeID(I.getType())); // restype.
1391     break;
1392   }
1393 
1394   Stream.EmitRecord(Code, Vals, AbbrevToUse);
1395   Vals.clear();
1396 }
1397 
1398 // Emit names for globals/functions etc.
WriteValueSymbolTable(const ValueSymbolTable & VST,const llvm_3_2::ValueEnumerator & VE,BitstreamWriter & Stream)1399 static void WriteValueSymbolTable(const ValueSymbolTable &VST,
1400                                   const llvm_3_2::ValueEnumerator &VE,
1401                                   BitstreamWriter &Stream) {
1402   if (VST.empty()) return;
1403   Stream.EnterSubblock(bitc::VALUE_SYMTAB_BLOCK_ID, 4);
1404 
1405   // FIXME: Set up the abbrev, we know how many values there are!
1406   // FIXME: We know if the type names can use 7-bit ascii.
1407   SmallVector<unsigned, 64> NameVals;
1408 
1409   for (ValueSymbolTable::const_iterator SI = VST.begin(), SE = VST.end();
1410        SI != SE; ++SI) {
1411 
1412     const ValueName &Name = *SI;
1413 
1414     // Figure out the encoding to use for the name.
1415     bool is7Bit = true;
1416     bool isChar6 = true;
1417     for (const char *C = Name.getKeyData(), *E = C+Name.getKeyLength();
1418          C != E; ++C) {
1419       if (isChar6)
1420         isChar6 = BitCodeAbbrevOp::isChar6(*C);
1421       if ((unsigned char)*C & 128) {
1422         is7Bit = false;
1423         break;  // don't bother scanning the rest.
1424       }
1425     }
1426 
1427     unsigned AbbrevToUse = VST_ENTRY_8_ABBREV;
1428 
1429     // VST_ENTRY:   [valueid, namechar x N]
1430     // VST_BBENTRY: [bbid, namechar x N]
1431     unsigned Code;
1432     if (isa<BasicBlock>(SI->getValue())) {
1433       Code = bitc::VST_CODE_BBENTRY;
1434       if (isChar6)
1435         AbbrevToUse = VST_BBENTRY_6_ABBREV;
1436     } else {
1437       Code = bitc::VST_CODE_ENTRY;
1438       if (isChar6)
1439         AbbrevToUse = VST_ENTRY_6_ABBREV;
1440       else if (is7Bit)
1441         AbbrevToUse = VST_ENTRY_7_ABBREV;
1442     }
1443 
1444     NameVals.push_back(VE.getValueID(SI->getValue()));
1445     for (const char *P = Name.getKeyData(),
1446          *E = Name.getKeyData()+Name.getKeyLength(); P != E; ++P)
1447       NameVals.push_back((unsigned char)*P);
1448 
1449     // Emit the finished record.
1450     Stream.EmitRecord(Code, NameVals, AbbrevToUse);
1451     NameVals.clear();
1452   }
1453   Stream.ExitBlock();
1454 }
1455 
WriteUseList(llvm_3_2::ValueEnumerator & VE,UseListOrder && Order,BitstreamWriter & Stream)1456 static void WriteUseList(llvm_3_2::ValueEnumerator &VE, UseListOrder &&Order,
1457                          BitstreamWriter &Stream) {
1458   assert(Order.Shuffle.size() >= 2 && "Shuffle too small");
1459   unsigned Code;
1460   if (isa<BasicBlock>(Order.V))
1461     Code = bitc::USELIST_CODE_BB;
1462   else
1463     Code = bitc::USELIST_CODE_DEFAULT;
1464 
1465   SmallVector<uint64_t, 64> Record;
1466   for (unsigned I : Order.Shuffle)
1467     Record.push_back(I);
1468   Record.push_back(VE.getValueID(Order.V));
1469   Stream.EmitRecord(Code, Record);
1470 }
1471 
WriteUseListBlock(const Function * F,llvm_3_2::ValueEnumerator & VE,BitstreamWriter & Stream)1472 static void WriteUseListBlock(const Function *F, llvm_3_2::ValueEnumerator &VE,
1473                               BitstreamWriter &Stream) {
1474   auto hasMore = [&]() {
1475     return !VE.UseListOrders.empty() && VE.UseListOrders.back().F == F;
1476   };
1477   if (!hasMore())
1478     // Nothing to do.
1479     return;
1480 
1481   Stream.EnterSubblock(bitc::USELIST_BLOCK_ID, 3);
1482   while (hasMore()) {
1483     WriteUseList(VE, std::move(VE.UseListOrders.back()), Stream);
1484     VE.UseListOrders.pop_back();
1485   }
1486   Stream.ExitBlock();
1487 }
1488 
1489 /// WriteFunction - Emit a function body to the module stream.
WriteFunction(const Function & F,llvm_3_2::ValueEnumerator & VE,BitstreamWriter & Stream)1490 static void WriteFunction(const Function &F, llvm_3_2::ValueEnumerator &VE,
1491                           BitstreamWriter &Stream) {
1492   Stream.EnterSubblock(bitc::FUNCTION_BLOCK_ID, 4);
1493   VE.incorporateFunction(F);
1494 
1495   SmallVector<unsigned, 64> Vals;
1496 
1497   // Emit the number of basic blocks, so the reader can create them ahead of
1498   // time.
1499   Vals.push_back(VE.getBasicBlocks().size());
1500   Stream.EmitRecord(bitc::FUNC_CODE_DECLAREBLOCKS, Vals);
1501   Vals.clear();
1502 
1503   // If there are function-local constants, emit them now.
1504   unsigned CstStart, CstEnd;
1505   VE.getFunctionConstantRange(CstStart, CstEnd);
1506   WriteConstants(CstStart, CstEnd, VE, Stream, false);
1507 
1508   // If there is function-local metadata, emit it now.
1509   WriteFunctionLocalMetadata(F, VE, Stream);
1510 
1511   // Keep a running idea of what the instruction ID is.
1512   unsigned InstID = CstEnd;
1513 
1514   bool NeedsMetadataAttachment = false;
1515 
1516   MDLocation *LastDL = nullptr;
1517 
1518   // Finally, emit all the instructions, in order.
1519   for (Function::const_iterator BB = F.begin(), E = F.end(); BB != E; ++BB)
1520     for (BasicBlock::const_iterator I = BB->begin(), E = BB->end();
1521          I != E; ++I) {
1522       WriteInstruction(*I, InstID, VE, Stream, Vals);
1523 
1524       if (!I->getType()->isVoidTy())
1525         ++InstID;
1526 
1527       // If the instruction has metadata, write a metadata attachment later.
1528       NeedsMetadataAttachment |= I->hasMetadataOtherThanDebugLoc();
1529 
1530       // If the instruction has a debug location, emit it.
1531       MDLocation *DL = I->getDebugLoc();
1532       if (!DL)
1533         continue;
1534 
1535       if (DL == LastDL) {
1536         // Just repeat the same debug loc as last time.
1537         Stream.EmitRecord(bitc::FUNC_CODE_DEBUG_LOC_AGAIN, Vals);
1538         continue;
1539       }
1540 
1541       Vals.push_back(DL->getLine());
1542       Vals.push_back(DL->getColumn());
1543       Vals.push_back(VE.getMetadataOrNullID(DL->getScope()));
1544       Vals.push_back(VE.getMetadataOrNullID(DL->getInlinedAt()));
1545       Stream.EmitRecord(bitc::FUNC_CODE_DEBUG_LOC, Vals);
1546       Vals.clear();
1547 
1548       // Fixme(pirama): The following line is missing from upstream
1549       // https://llvm.org/bugs/show_bug.cgi?id=23436
1550       LastDL = DL;
1551     }
1552 
1553   // Emit names for all the instructions etc.
1554   WriteValueSymbolTable(F.getValueSymbolTable(), VE, Stream);
1555 
1556   if (NeedsMetadataAttachment)
1557     WriteMetadataAttachment(F, VE, Stream);
1558   if (false)
1559     WriteUseListBlock(&F, VE, Stream);
1560   VE.purgeFunction();
1561   Stream.ExitBlock();
1562 }
1563 
1564 // Emit blockinfo, which defines the standard abbreviations etc.
WriteBlockInfo(const llvm_3_2::ValueEnumerator & VE,BitstreamWriter & Stream)1565 static void WriteBlockInfo(const llvm_3_2::ValueEnumerator &VE,
1566                            BitstreamWriter &Stream) {
1567   // We only want to emit block info records for blocks that have multiple
1568   // instances: CONSTANTS_BLOCK, FUNCTION_BLOCK and VALUE_SYMTAB_BLOCK.  Other
1569   // blocks can defined their abbrevs inline.
1570   Stream.EnterBlockInfoBlock(2);
1571 
1572   { // 8-bit fixed-width VST_ENTRY/VST_BBENTRY strings.
1573     BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1574     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3));
1575     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
1576     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1577     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 8));
1578     if (Stream.EmitBlockInfoAbbrev(bitc::VALUE_SYMTAB_BLOCK_ID,
1579                                    Abbv) != VST_ENTRY_8_ABBREV)
1580       llvm_unreachable("Unexpected abbrev ordering!");
1581   }
1582 
1583   { // 7-bit fixed width VST_ENTRY strings.
1584     BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1585     Abbv->Add(BitCodeAbbrevOp(bitc::VST_CODE_ENTRY));
1586     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
1587     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1588     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 7));
1589     if (Stream.EmitBlockInfoAbbrev(bitc::VALUE_SYMTAB_BLOCK_ID,
1590                                    Abbv) != VST_ENTRY_7_ABBREV)
1591       llvm_unreachable("Unexpected abbrev ordering!");
1592   }
1593   { // 6-bit char6 VST_ENTRY strings.
1594     BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1595     Abbv->Add(BitCodeAbbrevOp(bitc::VST_CODE_ENTRY));
1596     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
1597     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1598     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Char6));
1599     if (Stream.EmitBlockInfoAbbrev(bitc::VALUE_SYMTAB_BLOCK_ID,
1600                                    Abbv) != VST_ENTRY_6_ABBREV)
1601       llvm_unreachable("Unexpected abbrev ordering!");
1602   }
1603   { // 6-bit char6 VST_BBENTRY strings.
1604     BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1605     Abbv->Add(BitCodeAbbrevOp(bitc::VST_CODE_BBENTRY));
1606     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
1607     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1608     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Char6));
1609     if (Stream.EmitBlockInfoAbbrev(bitc::VALUE_SYMTAB_BLOCK_ID,
1610                                    Abbv) != VST_BBENTRY_6_ABBREV)
1611       llvm_unreachable("Unexpected abbrev ordering!");
1612   }
1613 
1614 
1615 
1616   { // SETTYPE abbrev for CONSTANTS_BLOCK.
1617     BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1618     Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_SETTYPE));
1619     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
1620                               Log2_32_Ceil(VE.getTypes().size()+1)));
1621     if (Stream.EmitBlockInfoAbbrev(bitc::CONSTANTS_BLOCK_ID,
1622                                    Abbv) != CONSTANTS_SETTYPE_ABBREV)
1623       llvm_unreachable("Unexpected abbrev ordering!");
1624   }
1625 
1626   { // INTEGER abbrev for CONSTANTS_BLOCK.
1627     BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1628     Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_INTEGER));
1629     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
1630     if (Stream.EmitBlockInfoAbbrev(bitc::CONSTANTS_BLOCK_ID,
1631                                    Abbv) != CONSTANTS_INTEGER_ABBREV)
1632       llvm_unreachable("Unexpected abbrev ordering!");
1633   }
1634 
1635   { // CE_CAST abbrev for CONSTANTS_BLOCK.
1636     BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1637     Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_CE_CAST));
1638     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 4));  // cast opc
1639     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,       // typeid
1640                               Log2_32_Ceil(VE.getTypes().size()+1)));
1641     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));    // value id
1642 
1643     if (Stream.EmitBlockInfoAbbrev(bitc::CONSTANTS_BLOCK_ID,
1644                                    Abbv) != CONSTANTS_CE_CAST_Abbrev)
1645       llvm_unreachable("Unexpected abbrev ordering!");
1646   }
1647   { // NULL abbrev for CONSTANTS_BLOCK.
1648     BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1649     Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_NULL));
1650     if (Stream.EmitBlockInfoAbbrev(bitc::CONSTANTS_BLOCK_ID,
1651                                    Abbv) != CONSTANTS_NULL_Abbrev)
1652       llvm_unreachable("Unexpected abbrev ordering!");
1653   }
1654 
1655   // FIXME: This should only use space for first class types!
1656 
1657   { // INST_LOAD abbrev for FUNCTION_BLOCK.
1658     BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1659     Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_LOAD));
1660     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Ptr
1661     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 4)); // Align
1662     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // volatile
1663     if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID,
1664                                    Abbv) != FUNCTION_INST_LOAD_ABBREV)
1665       llvm_unreachable("Unexpected abbrev ordering!");
1666   }
1667   { // INST_BINOP abbrev for FUNCTION_BLOCK.
1668     BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1669     Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_BINOP));
1670     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // LHS
1671     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // RHS
1672     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 4)); // opc
1673     if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID,
1674                                    Abbv) != FUNCTION_INST_BINOP_ABBREV)
1675       llvm_unreachable("Unexpected abbrev ordering!");
1676   }
1677   { // INST_BINOP_FLAGS abbrev for FUNCTION_BLOCK.
1678     BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1679     Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_BINOP));
1680     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // LHS
1681     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // RHS
1682     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 4)); // opc
1683     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 7)); // flags
1684     if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID,
1685                                    Abbv) != FUNCTION_INST_BINOP_FLAGS_ABBREV)
1686       llvm_unreachable("Unexpected abbrev ordering!");
1687   }
1688   { // INST_CAST abbrev for FUNCTION_BLOCK.
1689     BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1690     Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_CAST));
1691     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));    // OpVal
1692     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,       // dest ty
1693                               Log2_32_Ceil(VE.getTypes().size()+1)));
1694     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 4));  // opc
1695     if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID,
1696                                    Abbv) != FUNCTION_INST_CAST_ABBREV)
1697       llvm_unreachable("Unexpected abbrev ordering!");
1698   }
1699 
1700   { // INST_RET abbrev for FUNCTION_BLOCK.
1701     BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1702     Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_RET));
1703     if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID,
1704                                    Abbv) != FUNCTION_INST_RET_VOID_ABBREV)
1705       llvm_unreachable("Unexpected abbrev ordering!");
1706   }
1707   { // INST_RET abbrev for FUNCTION_BLOCK.
1708     BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1709     Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_RET));
1710     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // ValID
1711     if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID,
1712                                    Abbv) != FUNCTION_INST_RET_VAL_ABBREV)
1713       llvm_unreachable("Unexpected abbrev ordering!");
1714   }
1715   { // INST_UNREACHABLE abbrev for FUNCTION_BLOCK.
1716     BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1717     Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_UNREACHABLE));
1718     if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID,
1719                                    Abbv) != FUNCTION_INST_UNREACHABLE_ABBREV)
1720       llvm_unreachable("Unexpected abbrev ordering!");
1721   }
1722 
1723   Stream.ExitBlock();
1724 }
1725 
1726 /// WriteModule - Emit the specified module to the bitstream.
WriteModule(const Module * M,BitstreamWriter & Stream)1727 static void WriteModule(const Module *M, BitstreamWriter &Stream) {
1728   Stream.EnterSubblock(bitc::MODULE_BLOCK_ID, 3);
1729 
1730   SmallVector<unsigned, 1> Vals;
1731   // TODO(srhines): RenderScript is always version 0 for now.
1732   unsigned CurVersion = 0;
1733   if (CurVersion) {
1734     Vals.push_back(CurVersion);
1735     Stream.EmitRecord(bitc::MODULE_CODE_VERSION, Vals);
1736   }
1737 
1738   // Analyze the module, enumerating globals, functions, etc.
1739   llvm_3_2::ValueEnumerator VE(*M);
1740 
1741   // Emit blockinfo, which defines the standard abbreviations etc.
1742   WriteBlockInfo(VE, Stream);
1743 
1744   // Emit information about parameter attributes.
1745   WriteAttributeTable(VE, Stream);
1746 
1747   // Emit information describing all of the types in the module.
1748   WriteTypeTable(VE, Stream);
1749 
1750   // Emit top-level description of module, including target triple, inline asm,
1751   // descriptors for global variables, and function prototype info.
1752   WriteModuleInfo(M, VE, Stream);
1753 
1754   // Emit constants.
1755   WriteModuleConstants(VE, Stream);
1756 
1757   // Emit metadata.
1758   WriteModuleMetadata(M, VE, Stream);
1759 
1760   // Emit metadata.
1761   WriteModuleMetadataStore(M, Stream);
1762 
1763   // Emit names for globals/functions etc.
1764   WriteValueSymbolTable(M->getValueSymbolTable(), VE, Stream);
1765 
1766   // Emit module-level use-lists.
1767   if (false)
1768     WriteUseListBlock(nullptr, VE, Stream);
1769 
1770   // Emit function bodies.
1771   for (Module::const_iterator F = M->begin(), E = M->end(); F != E; ++F)
1772     if (!F->isDeclaration())
1773       WriteFunction(*F, VE, Stream);
1774 
1775   Stream.ExitBlock();
1776 }
1777 
1778 /// EmitDarwinBCHeader - If generating a bc file on darwin, we have to emit a
1779 /// header and trailer to make it compatible with the system archiver.  To do
1780 /// this we emit the following header, and then emit a trailer that pads the
1781 /// file out to be a multiple of 16 bytes.
1782 ///
1783 /// struct bc_header {
1784 ///   uint32_t Magic;         // 0x0B17C0DE
1785 ///   uint32_t Version;       // Version, currently always 0.
1786 ///   uint32_t BitcodeOffset; // Offset to traditional bitcode file.
1787 ///   uint32_t BitcodeSize;   // Size of traditional bitcode file.
1788 ///   uint32_t CPUType;       // CPU specifier.
1789 ///   ... potentially more later ...
1790 /// };
1791 enum {
1792   DarwinBCSizeFieldOffset = 3*4, // Offset to bitcode_size.
1793   DarwinBCHeaderSize = 5*4
1794 };
1795 
WriteInt32ToBuffer(uint32_t Value,SmallVectorImpl<char> & Buffer,uint32_t & Position)1796 static void WriteInt32ToBuffer(uint32_t Value, SmallVectorImpl<char> &Buffer,
1797                                uint32_t &Position) {
1798   Buffer[Position + 0] = (unsigned char) (Value >>  0);
1799   Buffer[Position + 1] = (unsigned char) (Value >>  8);
1800   Buffer[Position + 2] = (unsigned char) (Value >> 16);
1801   Buffer[Position + 3] = (unsigned char) (Value >> 24);
1802   Position += 4;
1803 }
1804 
EmitDarwinBCHeaderAndTrailer(SmallVectorImpl<char> & Buffer,const Triple & TT)1805 static void EmitDarwinBCHeaderAndTrailer(SmallVectorImpl<char> &Buffer,
1806                                          const Triple &TT) {
1807   unsigned CPUType = ~0U;
1808 
1809   // Match x86_64-*, i[3-9]86-*, powerpc-*, powerpc64-*, arm-*, thumb-*,
1810   // armv[0-9]-*, thumbv[0-9]-*, armv5te-*, or armv6t2-*. The CPUType is a magic
1811   // number from /usr/include/mach/machine.h.  It is ok to reproduce the
1812   // specific constants here because they are implicitly part of the Darwin ABI.
1813   enum {
1814     DARWIN_CPU_ARCH_ABI64      = 0x01000000,
1815     DARWIN_CPU_TYPE_X86        = 7,
1816     DARWIN_CPU_TYPE_ARM        = 12,
1817     DARWIN_CPU_TYPE_POWERPC    = 18
1818   };
1819 
1820   Triple::ArchType Arch = TT.getArch();
1821   if (Arch == Triple::x86_64)
1822     CPUType = DARWIN_CPU_TYPE_X86 | DARWIN_CPU_ARCH_ABI64;
1823   else if (Arch == Triple::x86)
1824     CPUType = DARWIN_CPU_TYPE_X86;
1825   else if (Arch == Triple::ppc)
1826     CPUType = DARWIN_CPU_TYPE_POWERPC;
1827   else if (Arch == Triple::ppc64)
1828     CPUType = DARWIN_CPU_TYPE_POWERPC | DARWIN_CPU_ARCH_ABI64;
1829   else if (Arch == Triple::arm || Arch == Triple::thumb)
1830     CPUType = DARWIN_CPU_TYPE_ARM;
1831 
1832   // Traditional Bitcode starts after header.
1833   assert(Buffer.size() >= DarwinBCHeaderSize &&
1834          "Expected header size to be reserved");
1835   unsigned BCOffset = DarwinBCHeaderSize;
1836   unsigned BCSize = Buffer.size()-DarwinBCHeaderSize;
1837 
1838   // Write the magic and version.
1839   unsigned Position = 0;
1840   WriteInt32ToBuffer(0x0B17C0DE , Buffer, Position);
1841   WriteInt32ToBuffer(0          , Buffer, Position); // Version.
1842   WriteInt32ToBuffer(BCOffset   , Buffer, Position);
1843   WriteInt32ToBuffer(BCSize     , Buffer, Position);
1844   WriteInt32ToBuffer(CPUType    , Buffer, Position);
1845 
1846   // If the file is not a multiple of 16 bytes, insert dummy padding.
1847   while (Buffer.size() & 15)
1848     Buffer.push_back(0);
1849 }
1850 
1851 /// WriteBitcodeToFile - Write the specified module to the specified output
1852 /// stream.
WriteBitcodeToFile(const Module * M,raw_ostream & Out)1853 void llvm_3_2::WriteBitcodeToFile(const Module *M, raw_ostream &Out) {
1854   SmallVector<char, 0> Buffer;
1855   Buffer.reserve(256*1024);
1856 
1857   // If this is darwin or another generic macho target, reserve space for the
1858   // header.
1859   Triple TT(M->getTargetTriple());
1860   if (TT.isOSDarwin())
1861     Buffer.insert(Buffer.begin(), DarwinBCHeaderSize, 0);
1862 
1863   // Emit the module into the buffer.
1864   {
1865     BitstreamWriter Stream(Buffer);
1866 
1867     // Emit the file header.
1868     Stream.Emit((unsigned)'B', 8);
1869     Stream.Emit((unsigned)'C', 8);
1870     Stream.Emit(0x0, 4);
1871     Stream.Emit(0xC, 4);
1872     Stream.Emit(0xE, 4);
1873     Stream.Emit(0xD, 4);
1874 
1875     // Emit the module.
1876     WriteModule(M, Stream);
1877   }
1878 
1879   if (TT.isOSDarwin())
1880     EmitDarwinBCHeaderAndTrailer(Buffer, TT);
1881 
1882   // Write the generated bitstream to "Out".
1883   Out.write((char*)&Buffer.front(), Buffer.size());
1884 }
1885