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_2_9.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/ValueSymbolTable.h"
28 #include "llvm/Support/ErrorHandling.h"
29 #include "llvm/Support/MathExtras.h"
30 #include "llvm/Support/Program.h"
31 #include "llvm/Support/raw_ostream.h"
32 #include <cctype>
33 #include <map>
34 using namespace llvm;
35 
36 // Redefine older bitcode opcodes for use here. Note that these come from
37 // LLVM 2.7 (which is what HC shipped with).
38 #define METADATA_NODE_2_7             2
39 #define METADATA_FN_NODE_2_7          3
40 #define METADATA_NAMED_NODE_2_7       5
41 #define METADATA_ATTACHMENT_2_7       7
42 #define FUNC_CODE_INST_CALL_2_7       22
43 #define FUNC_CODE_DEBUG_LOC_2_7       32
44 
45 // Redefine older bitcode opcodes for use here. Note that these come from
46 // LLVM 2.7 - 3.0.
47 #define TYPE_BLOCK_ID_OLD_3_0 10
48 #define TYPE_SYMTAB_BLOCK_ID_OLD_3_0 13
49 #define TYPE_CODE_STRUCT_OLD_3_0 10
50 
51 /// These are manifest constants used by the bitcode writer. They do not need to
52 /// be kept in sync with the reader, but need to be consistent within this file.
53 enum {
54   CurVersion = 0,
55 
56   // VALUE_SYMTAB_BLOCK abbrev id's.
57   VST_ENTRY_8_ABBREV = bitc::FIRST_APPLICATION_ABBREV,
58   VST_ENTRY_7_ABBREV,
59   VST_ENTRY_6_ABBREV,
60   VST_BBENTRY_6_ABBREV,
61 
62   // CONSTANTS_BLOCK abbrev id's.
63   CONSTANTS_SETTYPE_ABBREV = bitc::FIRST_APPLICATION_ABBREV,
64   CONSTANTS_INTEGER_ABBREV,
65   CONSTANTS_CE_CAST_Abbrev,
66   CONSTANTS_NULL_Abbrev,
67 
68   // FUNCTION_BLOCK abbrev id's.
69   FUNCTION_INST_LOAD_ABBREV = bitc::FIRST_APPLICATION_ABBREV,
70   FUNCTION_INST_BINOP_ABBREV,
71   FUNCTION_INST_BINOP_FLAGS_ABBREV,
72   FUNCTION_INST_CAST_ABBREV,
73   FUNCTION_INST_RET_VOID_ABBREV,
74   FUNCTION_INST_RET_VAL_ABBREV,
75   FUNCTION_INST_UNREACHABLE_ABBREV
76 };
77 
GetEncodedCastOpcode(unsigned Opcode)78 static unsigned GetEncodedCastOpcode(unsigned Opcode) {
79   switch (Opcode) {
80   default: llvm_unreachable("Unknown cast instruction!");
81   case Instruction::Trunc   : return bitc::CAST_TRUNC;
82   case Instruction::ZExt    : return bitc::CAST_ZEXT;
83   case Instruction::SExt    : return bitc::CAST_SEXT;
84   case Instruction::FPToUI  : return bitc::CAST_FPTOUI;
85   case Instruction::FPToSI  : return bitc::CAST_FPTOSI;
86   case Instruction::UIToFP  : return bitc::CAST_UITOFP;
87   case Instruction::SIToFP  : return bitc::CAST_SITOFP;
88   case Instruction::FPTrunc : return bitc::CAST_FPTRUNC;
89   case Instruction::FPExt   : return bitc::CAST_FPEXT;
90   case Instruction::PtrToInt: return bitc::CAST_PTRTOINT;
91   case Instruction::IntToPtr: return bitc::CAST_INTTOPTR;
92   case Instruction::BitCast : return bitc::CAST_BITCAST;
93   }
94 }
95 
GetEncodedBinaryOpcode(unsigned Opcode)96 static unsigned GetEncodedBinaryOpcode(unsigned Opcode) {
97   switch (Opcode) {
98   default: llvm_unreachable("Unknown binary instruction!");
99   case Instruction::Add:
100   case Instruction::FAdd: return bitc::BINOP_ADD;
101   case Instruction::Sub:
102   case Instruction::FSub: return bitc::BINOP_SUB;
103   case Instruction::Mul:
104   case Instruction::FMul: return bitc::BINOP_MUL;
105   case Instruction::UDiv: return bitc::BINOP_UDIV;
106   case Instruction::FDiv:
107   case Instruction::SDiv: return bitc::BINOP_SDIV;
108   case Instruction::URem: return bitc::BINOP_UREM;
109   case Instruction::FRem:
110   case Instruction::SRem: return bitc::BINOP_SREM;
111   case Instruction::Shl:  return bitc::BINOP_SHL;
112   case Instruction::LShr: return bitc::BINOP_LSHR;
113   case Instruction::AShr: return bitc::BINOP_ASHR;
114   case Instruction::And:  return bitc::BINOP_AND;
115   case Instruction::Or:   return bitc::BINOP_OR;
116   case Instruction::Xor:  return bitc::BINOP_XOR;
117   }
118 }
119 
WriteStringRecord(unsigned Code,StringRef Str,unsigned AbbrevToUse,BitstreamWriter & Stream)120 static void WriteStringRecord(unsigned Code, StringRef Str,
121                               unsigned AbbrevToUse, BitstreamWriter &Stream) {
122   SmallVector<unsigned, 64> Vals;
123 
124   // Code: [strchar x N]
125   for (unsigned i = 0, e = Str.size(); i != e; ++i) {
126     if (AbbrevToUse && !BitCodeAbbrevOp::isChar6(Str[i]))
127       AbbrevToUse = 0;
128     Vals.push_back(Str[i]);
129   }
130 
131   // Emit the finished record.
132   Stream.EmitRecord(Code, Vals, AbbrevToUse);
133 }
134 
135 // Emit information about parameter attributes.
WriteAttributeTable(const llvm_2_9::ValueEnumerator & VE,BitstreamWriter & Stream)136 static void WriteAttributeTable(const llvm_2_9::ValueEnumerator &VE,
137                                 BitstreamWriter &Stream) {
138   const std::vector<AttributeSet> &Attrs = VE.getAttributes();
139   if (Attrs.empty()) return;
140 
141   Stream.EnterSubblock(bitc::PARAMATTR_BLOCK_ID, 3);
142 
143   SmallVector<uint64_t, 64> Record;
144   for (unsigned i = 0, e = Attrs.size(); i != e; ++i) {
145     const AttributeSet &A = Attrs[i];
146     for (unsigned i = 0, e = A.getNumSlots(); i != e; ++i) {
147       Record.push_back(A.getSlotIndex(i));
148       Record.push_back(encodeLLVMAttributesForBitcode(A, A.getSlotIndex(i)));
149     }
150 
151     // This needs to use the 3.2 entry type
152     Stream.EmitRecord(bitc::PARAMATTR_CODE_ENTRY_OLD, Record);
153     Record.clear();
154   }
155 
156   Stream.ExitBlock();
157 }
158 
WriteTypeSymbolTable(const llvm_2_9::ValueEnumerator & VE,BitstreamWriter & Stream)159 static void WriteTypeSymbolTable(const llvm_2_9::ValueEnumerator &VE,
160                                  BitstreamWriter &Stream) {
161   const llvm_2_9::ValueEnumerator::TypeList &TypeList = VE.getTypes();
162   Stream.EnterSubblock(TYPE_SYMTAB_BLOCK_ID_OLD_3_0, 3);
163 
164   // 7-bit fixed width VST_CODE_ENTRY strings.
165   BitCodeAbbrev *Abbv = new BitCodeAbbrev();
166   Abbv->Add(BitCodeAbbrevOp(bitc::VST_CODE_ENTRY));
167   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
168                             Log2_32_Ceil(VE.getTypes().size()+1)));
169   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
170   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 7));
171   unsigned V7Abbrev = Stream.EmitAbbrev(Abbv);
172 
173   SmallVector<unsigned, 64> NameVals;
174 
175   for (unsigned i = 0, e = TypeList.size(); i != e; ++i) {
176     Type *T = TypeList[i];
177 
178     switch (T->getTypeID()) {
179     case Type::StructTyID: {
180       StructType *ST = cast<StructType>(T);
181       if (ST->isLiteral()) {
182         // Skip anonymous struct definitions in type symbol table
183         // FIXME(srhines)
184         break;
185       }
186 
187       // TST_ENTRY: [typeid, namechar x N]
188       NameVals.push_back(i);
189 
190       const std::string &Str = ST->getName();
191       bool is7Bit = true;
192       for (unsigned i = 0, e = Str.size(); i != e; ++i) {
193         NameVals.push_back((unsigned char)Str[i]);
194         if (Str[i] & 128)
195           is7Bit = false;
196       }
197 
198       // Emit the finished record.
199       Stream.EmitRecord(bitc::VST_CODE_ENTRY, NameVals, is7Bit ? V7Abbrev : 0);
200       NameVals.clear();
201 
202       break;
203     }
204     default: break;
205     }
206   }
207 
208   Stream.ExitBlock();
209 }
210 
211 /// WriteTypeTable - Write out the type table for a module.
WriteTypeTable(const llvm_2_9::ValueEnumerator & VE,BitstreamWriter & Stream)212 static void WriteTypeTable(const llvm_2_9::ValueEnumerator &VE,
213                            BitstreamWriter &Stream) {
214   const llvm_2_9::ValueEnumerator::TypeList &TypeList = VE.getTypes();
215 
216   Stream.EnterSubblock(TYPE_BLOCK_ID_OLD_3_0, 4 /*count from # abbrevs */);
217   SmallVector<uint64_t, 64> TypeVals;
218 
219   uint64_t NumBits = Log2_32_Ceil(VE.getTypes().size()+1);
220 
221   // Abbrev for TYPE_CODE_POINTER.
222   BitCodeAbbrev *Abbv = new BitCodeAbbrev();
223   Abbv->Add(BitCodeAbbrevOp(bitc::TYPE_CODE_POINTER));
224   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, NumBits));
225   Abbv->Add(BitCodeAbbrevOp(0));  // Addrspace = 0
226   unsigned PtrAbbrev = Stream.EmitAbbrev(Abbv);
227 
228   // Abbrev for TYPE_CODE_FUNCTION.
229   Abbv = new BitCodeAbbrev();
230   Abbv->Add(BitCodeAbbrevOp(bitc::TYPE_CODE_FUNCTION_OLD));
231   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1));  // isvararg
232   Abbv->Add(BitCodeAbbrevOp(0));  // FIXME: DEAD value, remove in LLVM 3.0
233   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
234   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, NumBits));
235   unsigned FunctionAbbrev = Stream.EmitAbbrev(Abbv);
236 
237 
238   // Abbrev for TYPE_CODE_STRUCT.
239   Abbv = new BitCodeAbbrev();
240   Abbv->Add(BitCodeAbbrevOp(TYPE_CODE_STRUCT_OLD_3_0));
241   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1));  // ispacked
242   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
243   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, NumBits));
244   unsigned StructAbbrev = Stream.EmitAbbrev(Abbv);
245 
246   // Abbrev for TYPE_CODE_ARRAY.
247   Abbv = new BitCodeAbbrev();
248   Abbv->Add(BitCodeAbbrevOp(bitc::TYPE_CODE_ARRAY));
249   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));   // size
250   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, NumBits));
251 
252   unsigned ArrayAbbrev = Stream.EmitAbbrev(Abbv);
253 
254   // Emit an entry count so the reader can reserve space.
255   TypeVals.push_back(TypeList.size());
256   Stream.EmitRecord(bitc::TYPE_CODE_NUMENTRY, TypeVals);
257   TypeVals.clear();
258 
259   // Loop over all of the types, emitting each in turn.
260   for (unsigned i = 0, e = TypeList.size(); i != e; ++i) {
261     Type *T = TypeList[i];
262     int AbbrevToUse = 0;
263     unsigned Code = 0;
264 
265     switch (T->getTypeID()) {
266     default: llvm_unreachable("Unknown type!");
267     case Type::VoidTyID:      Code = bitc::TYPE_CODE_VOID;   break;
268     case Type::FloatTyID:     Code = bitc::TYPE_CODE_FLOAT;  break;
269     case Type::DoubleTyID:    Code = bitc::TYPE_CODE_DOUBLE; break;
270     case Type::X86_FP80TyID:  Code = bitc::TYPE_CODE_X86_FP80; break;
271     case Type::FP128TyID:     Code = bitc::TYPE_CODE_FP128; break;
272     case Type::PPC_FP128TyID: Code = bitc::TYPE_CODE_PPC_FP128; break;
273     case Type::LabelTyID:     Code = bitc::TYPE_CODE_LABEL;  break;
274     case Type::MetadataTyID:  Code = bitc::TYPE_CODE_METADATA; break;
275     case Type::X86_MMXTyID:   Code = bitc::TYPE_CODE_X86_MMX; break;
276     case Type::IntegerTyID:
277       // INTEGER: [width]
278       Code = bitc::TYPE_CODE_INTEGER;
279       TypeVals.push_back(cast<IntegerType>(T)->getBitWidth());
280       break;
281     case Type::PointerTyID: {
282       PointerType *PTy = cast<PointerType>(T);
283       // POINTER: [pointee type, address space]
284       Code = bitc::TYPE_CODE_POINTER;
285       TypeVals.push_back(VE.getTypeID(PTy->getElementType()));
286       unsigned AddressSpace = PTy->getAddressSpace();
287       TypeVals.push_back(AddressSpace);
288       if (AddressSpace == 0) AbbrevToUse = PtrAbbrev;
289       break;
290     }
291     case Type::FunctionTyID: {
292       FunctionType *FT = cast<FunctionType>(T);
293       // FUNCTION: [isvararg, attrid, retty, paramty x N]
294       Code = bitc::TYPE_CODE_FUNCTION_OLD;
295       TypeVals.push_back(FT->isVarArg());
296       TypeVals.push_back(0);  // FIXME: DEAD: remove in llvm 3.0
297       TypeVals.push_back(VE.getTypeID(FT->getReturnType()));
298       for (unsigned i = 0, e = FT->getNumParams(); i != e; ++i)
299         TypeVals.push_back(VE.getTypeID(FT->getParamType(i)));
300       AbbrevToUse = FunctionAbbrev;
301       break;
302     }
303     case Type::StructTyID: {
304       StructType *ST = cast<StructType>(T);
305       // STRUCT: [ispacked, eltty x N]
306       TypeVals.push_back(ST->isPacked());
307       // Output all of the element types.
308       for (StructType::element_iterator I = ST->element_begin(),
309            E = ST->element_end(); I != E; ++I)
310         TypeVals.push_back(VE.getTypeID(*I));
311       Code = TYPE_CODE_STRUCT_OLD_3_0;
312       AbbrevToUse = StructAbbrev;
313       break;
314     }
315     case Type::ArrayTyID: {
316       ArrayType *AT = cast<ArrayType>(T);
317       // ARRAY: [numelts, eltty]
318       Code = bitc::TYPE_CODE_ARRAY;
319       TypeVals.push_back(AT->getNumElements());
320       TypeVals.push_back(VE.getTypeID(AT->getElementType()));
321       AbbrevToUse = ArrayAbbrev;
322       break;
323     }
324     case Type::VectorTyID: {
325       VectorType *VT = cast<VectorType>(T);
326       // VECTOR [numelts, eltty]
327       Code = bitc::TYPE_CODE_VECTOR;
328       TypeVals.push_back(VT->getNumElements());
329       TypeVals.push_back(VE.getTypeID(VT->getElementType()));
330       break;
331     }
332     }
333 
334     // Emit the finished record.
335     Stream.EmitRecord(Code, TypeVals, AbbrevToUse);
336     TypeVals.clear();
337   }
338 
339   Stream.ExitBlock();
340 
341   WriteTypeSymbolTable(VE, Stream);
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 
381 // Emit top-level description of module, including target triple, inline asm,
382 // descriptors for global variables, and function prototype info.
WriteModuleInfo(const Module * M,const llvm_2_9::ValueEnumerator & VE,BitstreamWriter & Stream)383 static void WriteModuleInfo(const Module *M,
384                             const llvm_2_9::ValueEnumerator &VE,
385                             BitstreamWriter &Stream) {
386   // Emit various pieces of data attached to a module.
387   if (!M->getTargetTriple().empty())
388     WriteStringRecord(bitc::MODULE_CODE_TRIPLE, M->getTargetTriple(),
389                       0/*TODO*/, Stream);
390   const std::string &DL = M->getDataLayoutStr();
391   if (!DL.empty())
392     WriteStringRecord(bitc::MODULE_CODE_DATALAYOUT, DL, 0 /*TODO*/, Stream);
393   if (!M->getModuleInlineAsm().empty())
394     WriteStringRecord(bitc::MODULE_CODE_ASM, M->getModuleInlineAsm(),
395                       0/*TODO*/, Stream);
396 
397   // Emit information about sections and GC, computing how many there are. Also
398   // compute the maximum alignment value.
399   std::map<std::string, unsigned> SectionMap;
400   std::map<std::string, unsigned> GCMap;
401   unsigned MaxAlignment = 0;
402   unsigned MaxGlobalType = 0;
403   for (const GlobalValue &GV : M->globals()) {
404     MaxAlignment = std::max(MaxAlignment, GV.getAlignment());
405     MaxGlobalType = std::max(MaxGlobalType, VE.getTypeID(GV.getType()));
406     if (GV.hasSection()) {
407       // Give section names unique ID's.
408       unsigned &Entry = SectionMap[GV.getSection()];
409       if (!Entry) {
410         WriteStringRecord(bitc::MODULE_CODE_SECTIONNAME, GV.getSection(),
411                           0/*TODO*/, Stream);
412         Entry = SectionMap.size();
413       }
414     }
415   }
416   for (const Function &F : *M) {
417     MaxAlignment = std::max(MaxAlignment, F.getAlignment());
418     if (F.hasSection()) {
419       // Give section names unique ID's.
420       unsigned &Entry = SectionMap[F.getSection()];
421       if (!Entry) {
422         WriteStringRecord(bitc::MODULE_CODE_SECTIONNAME, F.getSection(),
423                           0/*TODO*/, Stream);
424         Entry = SectionMap.size();
425       }
426     }
427     if (F.hasGC()) {
428       // Same for GC names.
429       unsigned &Entry = GCMap[F.getGC()];
430       if (!Entry) {
431         WriteStringRecord(bitc::MODULE_CODE_GCNAME, F.getGC(),
432                           0/*TODO*/, Stream);
433         Entry = GCMap.size();
434       }
435     }
436   }
437 
438   // Emit abbrev for globals, now that we know # sections and max alignment.
439   unsigned SimpleGVarAbbrev = 0;
440   if (!M->global_empty()) {
441     // Add an abbrev for common globals with no visibility or thread localness.
442     BitCodeAbbrev *Abbv = new BitCodeAbbrev();
443     Abbv->Add(BitCodeAbbrevOp(bitc::MODULE_CODE_GLOBALVAR));
444     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
445                               Log2_32_Ceil(MaxGlobalType+1)));
446     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1));      // Constant.
447     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));        // Initializer.
448     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 4));      // Linkage.
449     if (MaxAlignment == 0)                                      // Alignment.
450       Abbv->Add(BitCodeAbbrevOp(0));
451     else {
452       unsigned MaxEncAlignment = Log2_32(MaxAlignment)+1;
453       Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
454                                Log2_32_Ceil(MaxEncAlignment+1)));
455     }
456     if (SectionMap.empty())                                    // Section.
457       Abbv->Add(BitCodeAbbrevOp(0));
458     else
459       Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
460                                Log2_32_Ceil(SectionMap.size()+1)));
461     // Don't bother emitting vis + thread local.
462     SimpleGVarAbbrev = Stream.EmitAbbrev(Abbv);
463   }
464 
465   // Emit the global variable information.
466   SmallVector<unsigned, 64> Vals;
467   for (const GlobalVariable &GV : M->globals()) {
468     unsigned AbbrevToUse = 0;
469 
470     // GLOBALVAR: [type, isconst, initid,
471     //             linkage, alignment, section, visibility, threadlocal,
472     //             unnamed_addr]
473     Vals.push_back(VE.getTypeID(GV.getType()));
474     Vals.push_back(GV.isConstant());
475     Vals.push_back(GV.isDeclaration() ? 0 :
476                    (VE.getValueID(GV.getInitializer()) + 1));
477     Vals.push_back(getEncodedLinkage(GV));
478     Vals.push_back(Log2_32(GV.getAlignment())+1);
479     Vals.push_back(GV.hasSection() ? SectionMap[GV.getSection()] : 0);
480     if (GV.isThreadLocal() ||
481         GV.getVisibility() != GlobalValue::DefaultVisibility ||
482         GV.getUnnamedAddr() != GlobalValue::UnnamedAddr::None) {
483       Vals.push_back(getEncodedVisibility(GV));
484       Vals.push_back(GV.isThreadLocal());
485       Vals.push_back(GV.getUnnamedAddr() != GlobalValue::UnnamedAddr::None);
486     } else {
487       AbbrevToUse = SimpleGVarAbbrev;
488     }
489 
490     Stream.EmitRecord(bitc::MODULE_CODE_GLOBALVAR, Vals, AbbrevToUse);
491     Vals.clear();
492   }
493 
494   // Emit the function proto information.
495   for (const Function &F : *M) {
496     // FUNCTION:  [type, callingconv, isproto, paramattr,
497     //             linkage, alignment, section, visibility, gc, unnamed_addr]
498     Vals.push_back(VE.getTypeID(F.getType()));
499     Vals.push_back(F.getCallingConv());
500     Vals.push_back(F.isDeclaration());
501     Vals.push_back(getEncodedLinkage(F));
502     Vals.push_back(VE.getAttributeID(F.getAttributes()));
503     Vals.push_back(Log2_32(F.getAlignment())+1);
504     Vals.push_back(F.hasSection() ? SectionMap[F.getSection()] : 0);
505     Vals.push_back(getEncodedVisibility(F));
506     Vals.push_back(F.hasGC() ? GCMap[F.getGC()] : 0);
507     Vals.push_back(F.getUnnamedAddr() != GlobalValue::UnnamedAddr::None);
508 
509     unsigned AbbrevToUse = 0;
510     Stream.EmitRecord(bitc::MODULE_CODE_FUNCTION, Vals, AbbrevToUse);
511     Vals.clear();
512   }
513 
514   // Emit the alias information.
515   for (const GlobalAlias &A : M->aliases()) {
516     Vals.push_back(VE.getTypeID(A.getType()));
517     Vals.push_back(VE.getValueID(A.getAliasee()));
518     Vals.push_back(getEncodedLinkage(A));
519     Vals.push_back(getEncodedVisibility(A));
520     unsigned AbbrevToUse = 0;
521     Stream.EmitRecord(bitc::MODULE_CODE_ALIAS_OLD, Vals, AbbrevToUse);
522     Vals.clear();
523   }
524 }
525 
GetOptimizationFlags(const Value * V)526 static uint64_t GetOptimizationFlags(const Value *V) {
527   uint64_t Flags = 0;
528 
529   if (const auto *OBO = dyn_cast<OverflowingBinaryOperator>(V)) {
530     if (OBO->hasNoSignedWrap())
531       Flags |= 1 << bitc::OBO_NO_SIGNED_WRAP;
532     if (OBO->hasNoUnsignedWrap())
533       Flags |= 1 << bitc::OBO_NO_UNSIGNED_WRAP;
534   } else if (const auto *PEO = dyn_cast<PossiblyExactOperator>(V)) {
535     if (PEO->isExact())
536       Flags |= 1 << bitc::PEO_EXACT;
537   }
538 
539   return Flags;
540 }
541 
WriteValueAsMetadata(const ValueAsMetadata * MD,const llvm_2_9::ValueEnumerator & VE,BitstreamWriter & Stream,SmallVectorImpl<uint64_t> & Record)542 static void WriteValueAsMetadata(const ValueAsMetadata *MD,
543                                  const llvm_2_9::ValueEnumerator &VE,
544                                  BitstreamWriter &Stream,
545                                  SmallVectorImpl<uint64_t> &Record) {
546   // Mimic an MDNode with a value as one operand.
547   Value *V = MD->getValue();
548   Record.push_back(VE.getTypeID(V->getType()));
549   Record.push_back(VE.getValueID(V));
550   Stream.EmitRecord(METADATA_NODE_2_7, Record, 0);
551   Record.clear();
552 }
553 
WriteMDTuple(const MDTuple * N,const llvm_2_9::ValueEnumerator & VE,BitstreamWriter & Stream,SmallVectorImpl<uint64_t> & Record,unsigned Abbrev)554 static void WriteMDTuple(const MDTuple *N, const llvm_2_9::ValueEnumerator &VE,
555                          BitstreamWriter &Stream,
556                          SmallVectorImpl<uint64_t> &Record, unsigned Abbrev) {
557   for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i) {
558     Metadata *MD = N->getOperand(i);
559     assert(!(MD && isa<LocalAsMetadata>(MD)) &&
560            "Unexpected function-local metadata");
561     if (!MD) {
562       // TODO(srhines): I don't believe this case can exist for RS.
563       Record.push_back(VE.getTypeID(llvm::Type::getVoidTy(N->getContext())));
564       Record.push_back(0);
565     } else if (const auto *MDC = dyn_cast<ConstantAsMetadata>(MD)) {
566       Record.push_back(VE.getTypeID(MDC->getType()));
567       Record.push_back(VE.getValueID(MDC->getValue()));
568     } else {
569       Record.push_back(VE.getTypeID(
570           llvm::Type::getMetadataTy(N->getContext())));
571       Record.push_back(VE.getMetadataID(MD));
572     }
573   }
574   Stream.EmitRecord(METADATA_NODE_2_7, Record, Abbrev);
575   Record.clear();
576 }
577 
578 /*static void WriteMDLocation(const MDLocation *N, const llvm_2_9::ValueEnumerator &VE,
579                             BitstreamWriter &Stream,
580                             SmallVectorImpl<uint64_t> &Record,
581                             unsigned Abbrev) {
582   Record.push_back(N->isDistinct());
583   Record.push_back(N->getLine());
584   Record.push_back(N->getColumn());
585   Record.push_back(VE.getMetadataID(N->getScope()));
586   Record.push_back(VE.getMetadataOrNullID(N->getInlinedAt()));
587 
588   Stream.EmitRecord(bitc::METADATA_LOCATION, Record, Abbrev);
589   Record.clear();
590 }
591 
592 static void WriteGenericDebugNode(const GenericDebugNode *,
593                                   const llvm_2_9::ValueEnumerator &, BitstreamWriter &,
594                                   SmallVectorImpl<uint64_t> &, unsigned) {
595   llvm_unreachable("unimplemented");
596 }*/
597 
WriteModuleMetadata(const Module * M,const llvm_2_9::ValueEnumerator & VE,BitstreamWriter & Stream)598 static void WriteModuleMetadata(const Module *M,
599                                 const llvm_2_9::ValueEnumerator &VE,
600                                 BitstreamWriter &Stream) {
601   const auto &MDs = VE.getMDs();
602   if (MDs.empty() && M->named_metadata_empty())
603     return;
604 
605   // RenderScript files *ALWAYS* have metadata!
606   Stream.EnterSubblock(bitc::METADATA_BLOCK_ID, 3);
607 
608   unsigned MDSAbbrev = 0;
609   if (VE.hasMDString()) {
610     // Abbrev for METADATA_STRING.
611     BitCodeAbbrev *Abbv = new BitCodeAbbrev();
612     Abbv->Add(BitCodeAbbrevOp(bitc::METADATA_STRING_OLD));
613     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
614     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 8));
615     MDSAbbrev = Stream.EmitAbbrev(Abbv);
616   }
617 
618   unsigned MDLocationAbbrev = 0;
619   if (VE.hasDILocation()) {
620     // TODO(srhines): Should be unreachable for RenderScript.
621     // Abbrev for METADATA_LOCATION.
622     //
623     // Assume the column is usually under 128, and always output the inlined-at
624     // location (it's never more expensive than building an array size 1).
625     BitCodeAbbrev *Abbv = new BitCodeAbbrev();
626     Abbv->Add(BitCodeAbbrevOp(bitc::METADATA_LOCATION));
627     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1));
628     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
629     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
630     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
631     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
632     MDLocationAbbrev = Stream.EmitAbbrev(Abbv);
633   }
634 
635   unsigned NameAbbrev = 0;
636   if (!M->named_metadata_empty()) {
637     // Abbrev for METADATA_NAME.
638     BitCodeAbbrev *Abbv = new BitCodeAbbrev();
639     Abbv->Add(BitCodeAbbrevOp(bitc::METADATA_NAME));
640     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
641     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 8));
642     NameAbbrev = Stream.EmitAbbrev(Abbv);
643   }
644 
645   unsigned MDTupleAbbrev = 0;
646   //unsigned GenericDebugNodeAbbrev = 0;
647   SmallVector<uint64_t, 64> Record;
648   for (const Metadata *MD : MDs) {
649     if (const MDNode *N = dyn_cast<MDNode>(MD)) {
650       switch (N->getMetadataID()) {
651       default:
652         llvm_unreachable("Invalid MDNode subclass");
653 #define HANDLE_SPECIALIZED_MDNODE_LEAF(CLASS)
654 #define HANDLE_MDNODE_LEAF(CLASS)                                              \
655   case Metadata::CLASS##Kind:                                                  \
656     Write##CLASS(cast<CLASS>(N), VE, Stream, Record, CLASS##Abbrev);           \
657     continue;
658 #include "llvm/IR/Metadata.def"
659       }
660     }
661     if (const auto *MDC = dyn_cast<ConstantAsMetadata>(MD)) {
662       WriteValueAsMetadata(MDC, VE, Stream, Record);
663       continue;
664     }
665     const MDString *MDS = cast<MDString>(MD);
666     // Code: [strchar x N]
667     Record.append(MDS->bytes_begin(), MDS->bytes_end());
668 
669     // Emit the finished record.
670     Stream.EmitRecord(bitc::METADATA_STRING_OLD, Record, MDSAbbrev);
671     Record.clear();
672   }
673 
674   // Write named metadata.
675   for (const NamedMDNode &NMD : M->named_metadata()) {
676     // Write name.
677     StringRef Str = NMD.getName();
678     Record.append(Str.bytes_begin(), Str.bytes_end());
679     Stream.EmitRecord(bitc::METADATA_NAME, Record, NameAbbrev);
680     Record.clear();
681 
682     // Write named metadata operands.
683     for (const MDNode *N : NMD.operands())
684       Record.push_back(VE.getMetadataID(N));
685     Stream.EmitRecord(METADATA_NAMED_NODE_2_7, Record, 0);
686     Record.clear();
687   }
688 
689   Stream.ExitBlock();
690 }
691 
WriteFunctionLocalMetadata(const Function & F,const llvm_2_9::ValueEnumerator & VE,BitstreamWriter & Stream)692 static void WriteFunctionLocalMetadata(const Function &F,
693                                        const llvm_2_9::ValueEnumerator &VE,
694                                        BitstreamWriter &Stream) {
695   bool StartedMetadataBlock = false;
696   SmallVector<uint64_t, 64> Record;
697   const SmallVectorImpl<const LocalAsMetadata *> &MDs =
698       VE.getFunctionLocalMDs();
699   for (unsigned i = 0, e = MDs.size(); i != e; ++i) {
700     assert(MDs[i] && "Expected valid function-local metadata");
701     if (!StartedMetadataBlock) {
702       Stream.EnterSubblock(bitc::METADATA_BLOCK_ID, 3);
703       StartedMetadataBlock = true;
704     }
705     WriteValueAsMetadata(MDs[i], VE, Stream, Record);
706   }
707 
708   if (StartedMetadataBlock)
709     Stream.ExitBlock();
710 }
711 
WriteMetadataAttachment(const Function & F,const llvm_2_9::ValueEnumerator & VE,BitstreamWriter & Stream)712 static void WriteMetadataAttachment(const Function &F,
713                                     const llvm_2_9::ValueEnumerator &VE,
714                                     BitstreamWriter &Stream) {
715   Stream.EnterSubblock(bitc::METADATA_ATTACHMENT_ID, 3);
716 
717   SmallVector<uint64_t, 64> Record;
718 
719   // Write metadata attachments
720   // METADATA_ATTACHMENT - [m x [value, [n x [id, mdnode]]]
721   SmallVector<std::pair<unsigned, MDNode *>, 4> MDs;
722 
723   for (Function::const_iterator BB = F.begin(), E = F.end(); BB != E; ++BB)
724     for (BasicBlock::const_iterator I = BB->begin(), E = BB->end();
725          I != E; ++I) {
726       MDs.clear();
727       I->getAllMetadataOtherThanDebugLoc(MDs);
728 
729       // If no metadata, ignore instruction.
730       if (MDs.empty()) continue;
731 
732       Record.push_back(VE.getInstructionID(&*I));
733 
734       for (unsigned i = 0, e = MDs.size(); i != e; ++i) {
735         Record.push_back(MDs[i].first);
736         Record.push_back(VE.getMetadataID(MDs[i].second));
737       }
738       Stream.EmitRecord(METADATA_ATTACHMENT_2_7, Record, 0);
739       Record.clear();
740     }
741 
742   Stream.ExitBlock();
743 }
744 
WriteModuleMetadataStore(const Module * M,BitstreamWriter & Stream)745 static void WriteModuleMetadataStore(const Module *M, BitstreamWriter &Stream) {
746   SmallVector<uint64_t, 64> Record;
747 
748   // Write metadata kinds
749   // METADATA_KIND - [n x [id, name]]
750   SmallVector<StringRef, 4> Names;
751   M->getMDKindNames(Names);
752 
753   if (Names.empty()) return;
754 
755   Stream.EnterSubblock(bitc::METADATA_BLOCK_ID, 3);
756 
757   for (unsigned MDKindID = 0, e = Names.size(); MDKindID != e; ++MDKindID) {
758     Record.push_back(MDKindID);
759     StringRef KName = Names[MDKindID];
760     Record.append(KName.begin(), KName.end());
761 
762     Stream.EmitRecord(bitc::METADATA_KIND, Record, 0);
763     Record.clear();
764   }
765 
766   Stream.ExitBlock();
767 }
768 
WriteConstants(unsigned FirstVal,unsigned LastVal,const llvm_2_9::ValueEnumerator & VE,BitstreamWriter & Stream,bool isGlobal)769 static void WriteConstants(unsigned FirstVal, unsigned LastVal,
770                            const llvm_2_9::ValueEnumerator &VE,
771                            BitstreamWriter &Stream, bool isGlobal) {
772   if (FirstVal == LastVal) return;
773 
774   Stream.EnterSubblock(bitc::CONSTANTS_BLOCK_ID, 4);
775 
776   unsigned AggregateAbbrev = 0;
777   unsigned String8Abbrev = 0;
778   unsigned CString7Abbrev = 0;
779   unsigned CString6Abbrev = 0;
780   // If this is a constant pool for the module, emit module-specific abbrevs.
781   if (isGlobal) {
782     // Abbrev for CST_CODE_AGGREGATE.
783     BitCodeAbbrev *Abbv = new BitCodeAbbrev();
784     Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_AGGREGATE));
785     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
786     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, Log2_32_Ceil(LastVal+1)));
787     AggregateAbbrev = Stream.EmitAbbrev(Abbv);
788 
789     // Abbrev for CST_CODE_STRING.
790     Abbv = new BitCodeAbbrev();
791     Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_STRING));
792     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
793     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 8));
794     String8Abbrev = Stream.EmitAbbrev(Abbv);
795     // Abbrev for CST_CODE_CSTRING.
796     Abbv = new BitCodeAbbrev();
797     Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_CSTRING));
798     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
799     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 7));
800     CString7Abbrev = Stream.EmitAbbrev(Abbv);
801     // Abbrev for CST_CODE_CSTRING.
802     Abbv = new BitCodeAbbrev();
803     Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_CSTRING));
804     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
805     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Char6));
806     CString6Abbrev = Stream.EmitAbbrev(Abbv);
807   }
808 
809   SmallVector<uint64_t, 64> Record;
810 
811   const llvm_2_9::ValueEnumerator::ValueList &Vals = VE.getValues();
812   Type *LastTy = nullptr;
813   for (unsigned i = FirstVal; i != LastVal; ++i) {
814     const Value *V = Vals[i].first;
815     // If we need to switch types, do so now.
816     if (V->getType() != LastTy) {
817       LastTy = V->getType();
818       Record.push_back(VE.getTypeID(LastTy));
819       Stream.EmitRecord(bitc::CST_CODE_SETTYPE, Record,
820                         CONSTANTS_SETTYPE_ABBREV);
821       Record.clear();
822     }
823 
824     if (const InlineAsm *IA = dyn_cast<InlineAsm>(V)) {
825       Record.push_back(unsigned(IA->hasSideEffects()) |
826                        unsigned(IA->isAlignStack()) << 1);
827 
828       // Add the asm string.
829       const std::string &AsmStr = IA->getAsmString();
830       Record.push_back(AsmStr.size());
831       for (unsigned i = 0, e = AsmStr.size(); i != e; ++i)
832         Record.push_back(AsmStr[i]);
833 
834       // Add the constraint string.
835       const std::string &ConstraintStr = IA->getConstraintString();
836       Record.push_back(ConstraintStr.size());
837       for (unsigned i = 0, e = ConstraintStr.size(); i != e; ++i)
838         Record.push_back(ConstraintStr[i]);
839       Stream.EmitRecord(bitc::CST_CODE_INLINEASM, Record);
840       Record.clear();
841       continue;
842     }
843     const Constant *C = cast<Constant>(V);
844     unsigned Code = -1U;
845     unsigned AbbrevToUse = 0;
846     if (C->isNullValue()) {
847       Code = bitc::CST_CODE_NULL;
848     } else if (isa<UndefValue>(C)) {
849       Code = bitc::CST_CODE_UNDEF;
850     } else if (const ConstantInt *IV = dyn_cast<ConstantInt>(C)) {
851       if (IV->getBitWidth() <= 64) {
852         uint64_t V = IV->getSExtValue();
853         if ((int64_t)V >= 0)
854           Record.push_back(V << 1);
855         else
856           Record.push_back((-V << 1) | 1);
857         Code = bitc::CST_CODE_INTEGER;
858         AbbrevToUse = CONSTANTS_INTEGER_ABBREV;
859       } else {                             // Wide integers, > 64 bits in size.
860         // We have an arbitrary precision integer value to write whose
861         // bit width is > 64. However, in canonical unsigned integer
862         // format it is likely that the high bits are going to be zero.
863         // So, we only write the number of active words.
864         unsigned NWords = IV->getValue().getActiveWords();
865         const uint64_t *RawWords = IV->getValue().getRawData();
866         for (unsigned i = 0; i != NWords; ++i) {
867           int64_t V = RawWords[i];
868           if (V >= 0)
869             Record.push_back(V << 1);
870           else
871             Record.push_back((-V << 1) | 1);
872         }
873         Code = bitc::CST_CODE_WIDE_INTEGER;
874       }
875     } else if (const ConstantFP *CFP = dyn_cast<ConstantFP>(C)) {
876       Code = bitc::CST_CODE_FLOAT;
877       Type *Ty = CFP->getType();
878       if (Ty->isFloatTy() || Ty->isDoubleTy()) {
879         Record.push_back(CFP->getValueAPF().bitcastToAPInt().getZExtValue());
880       } else if (Ty->isX86_FP80Ty()) {
881         // api needed to prevent premature destruction
882         // bits are not in the same order as a normal i80 APInt, compensate.
883         APInt api = CFP->getValueAPF().bitcastToAPInt();
884         const uint64_t *p = api.getRawData();
885         Record.push_back((p[1] << 48) | (p[0] >> 16));
886         Record.push_back(p[0] & 0xffffLL);
887       } else if (Ty->isFP128Ty() || Ty->isPPC_FP128Ty()) {
888         APInt api = CFP->getValueAPF().bitcastToAPInt();
889         const uint64_t *p = api.getRawData();
890         Record.push_back(p[0]);
891         Record.push_back(p[1]);
892       } else {
893         assert (0 && "Unknown FP type!");
894       }
895     } else if (isa<ConstantDataSequential>(C) &&
896                cast<ConstantDataSequential>(C)->isString()) {
897       const ConstantDataSequential *Str = cast<ConstantDataSequential>(C);
898       // Emit constant strings specially.
899       unsigned NumElts = Str->getNumElements();
900       // If this is a null-terminated string, use the denser CSTRING encoding.
901       if (Str->isCString()) {
902         Code = bitc::CST_CODE_CSTRING;
903         --NumElts;  // Don't encode the null, which isn't allowed by char6.
904       } else {
905         Code = bitc::CST_CODE_STRING;
906         AbbrevToUse = String8Abbrev;
907       }
908       bool isCStr7 = Code == bitc::CST_CODE_CSTRING;
909       bool isCStrChar6 = Code == bitc::CST_CODE_CSTRING;
910       for (unsigned i = 0; i != NumElts; ++i) {
911         unsigned char V = Str->getElementAsInteger(i);
912         Record.push_back(V);
913         isCStr7 &= (V & 128) == 0;
914         if (isCStrChar6)
915           isCStrChar6 = BitCodeAbbrevOp::isChar6(V);
916       }
917 
918       if (isCStrChar6)
919         AbbrevToUse = CString6Abbrev;
920       else if (isCStr7)
921         AbbrevToUse = CString7Abbrev;
922     } else if (const ConstantDataSequential *CDS =
923                   dyn_cast<ConstantDataSequential>(C)) {
924       // We must replace ConstantDataSequential's representation with the
925       // legacy ConstantArray/ConstantVector/ConstantStruct version.
926       // ValueEnumerator is similarly modified to mark the appropriate
927       // Constants as used (so they are emitted).
928       Code = bitc::CST_CODE_AGGREGATE;
929       for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i)
930         Record.push_back(VE.getValueID(CDS->getElementAsConstant(i)));
931       AbbrevToUse = AggregateAbbrev;
932     } else if (isa<ConstantArray>(C) || isa<ConstantStruct>(C) ||
933                isa<ConstantVector>(C)) {
934       Code = bitc::CST_CODE_AGGREGATE;
935       for (unsigned i = 0, e = C->getNumOperands(); i != e; ++i)
936         Record.push_back(VE.getValueID(C->getOperand(i)));
937       AbbrevToUse = AggregateAbbrev;
938     } else if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(C)) {
939       switch (CE->getOpcode()) {
940       default:
941         if (Instruction::isCast(CE->getOpcode())) {
942           Code = bitc::CST_CODE_CE_CAST;
943           Record.push_back(GetEncodedCastOpcode(CE->getOpcode()));
944           Record.push_back(VE.getTypeID(C->getOperand(0)->getType()));
945           Record.push_back(VE.getValueID(C->getOperand(0)));
946           AbbrevToUse = CONSTANTS_CE_CAST_Abbrev;
947         } else {
948           assert(CE->getNumOperands() == 2 && "Unknown constant expr!");
949           Code = bitc::CST_CODE_CE_BINOP;
950           Record.push_back(GetEncodedBinaryOpcode(CE->getOpcode()));
951           Record.push_back(VE.getValueID(C->getOperand(0)));
952           Record.push_back(VE.getValueID(C->getOperand(1)));
953           uint64_t Flags = GetOptimizationFlags(CE);
954           if (Flags != 0)
955             Record.push_back(Flags);
956         }
957         break;
958       case Instruction::GetElementPtr:
959         Code = bitc::CST_CODE_CE_GEP;
960         if (cast<GEPOperator>(C)->isInBounds())
961           Code = bitc::CST_CODE_CE_INBOUNDS_GEP;
962         for (unsigned i = 0, e = CE->getNumOperands(); i != e; ++i) {
963           Record.push_back(VE.getTypeID(C->getOperand(i)->getType()));
964           Record.push_back(VE.getValueID(C->getOperand(i)));
965         }
966         break;
967       case Instruction::Select:
968         Code = bitc::CST_CODE_CE_SELECT;
969         Record.push_back(VE.getValueID(C->getOperand(0)));
970         Record.push_back(VE.getValueID(C->getOperand(1)));
971         Record.push_back(VE.getValueID(C->getOperand(2)));
972         break;
973       case Instruction::ExtractElement:
974         Code = bitc::CST_CODE_CE_EXTRACTELT;
975         Record.push_back(VE.getTypeID(C->getOperand(0)->getType()));
976         Record.push_back(VE.getValueID(C->getOperand(0)));
977         Record.push_back(VE.getValueID(C->getOperand(1)));
978         break;
979       case Instruction::InsertElement:
980         Code = bitc::CST_CODE_CE_INSERTELT;
981         Record.push_back(VE.getValueID(C->getOperand(0)));
982         Record.push_back(VE.getValueID(C->getOperand(1)));
983         Record.push_back(VE.getValueID(C->getOperand(2)));
984         break;
985       case Instruction::ShuffleVector:
986         // If the return type and argument types are the same, this is a
987         // standard shufflevector instruction.  If the types are different,
988         // then the shuffle is widening or truncating the input vectors, and
989         // the argument type must also be encoded.
990         if (C->getType() == C->getOperand(0)->getType()) {
991           Code = bitc::CST_CODE_CE_SHUFFLEVEC;
992         } else {
993           Code = bitc::CST_CODE_CE_SHUFVEC_EX;
994           Record.push_back(VE.getTypeID(C->getOperand(0)->getType()));
995         }
996         Record.push_back(VE.getValueID(C->getOperand(0)));
997         Record.push_back(VE.getValueID(C->getOperand(1)));
998         Record.push_back(VE.getValueID(C->getOperand(2)));
999         break;
1000       case Instruction::ICmp:
1001       case Instruction::FCmp:
1002         Code = bitc::CST_CODE_CE_CMP;
1003         Record.push_back(VE.getTypeID(C->getOperand(0)->getType()));
1004         Record.push_back(VE.getValueID(C->getOperand(0)));
1005         Record.push_back(VE.getValueID(C->getOperand(1)));
1006         Record.push_back(CE->getPredicate());
1007         break;
1008       }
1009     } else if (const BlockAddress *BA = dyn_cast<BlockAddress>(C)) {
1010       Code = bitc::CST_CODE_BLOCKADDRESS;
1011       Record.push_back(VE.getTypeID(BA->getFunction()->getType()));
1012       Record.push_back(VE.getValueID(BA->getFunction()));
1013       Record.push_back(VE.getGlobalBasicBlockID(BA->getBasicBlock()));
1014     } else {
1015 #ifndef NDEBUG
1016       C->dump();
1017 #endif
1018       llvm_unreachable("Unknown constant!");
1019     }
1020     Stream.EmitRecord(Code, Record, AbbrevToUse);
1021     Record.clear();
1022   }
1023 
1024   Stream.ExitBlock();
1025 }
1026 
WriteModuleConstants(const llvm_2_9::ValueEnumerator & VE,BitstreamWriter & Stream)1027 static void WriteModuleConstants(const llvm_2_9::ValueEnumerator &VE,
1028                                  BitstreamWriter &Stream) {
1029   const llvm_2_9::ValueEnumerator::ValueList &Vals = VE.getValues();
1030 
1031   // Find the first constant to emit, which is the first non-globalvalue value.
1032   // We know globalvalues have been emitted by WriteModuleInfo.
1033   for (unsigned i = 0, e = Vals.size(); i != e; ++i) {
1034     if (!isa<GlobalValue>(Vals[i].first)) {
1035       WriteConstants(i, Vals.size(), VE, Stream, true);
1036       return;
1037     }
1038   }
1039 }
1040 
1041 /// PushValueAndType - The file has to encode both the value and type id for
1042 /// many values, because we need to know what type to create for forward
1043 /// references.  However, most operands are not forward references, so this type
1044 /// field is not needed.
1045 ///
1046 /// This function adds V's value ID to Vals.  If the value ID is higher than the
1047 /// instruction ID, then it is a forward reference, and it also includes the
1048 /// type ID.
PushValueAndType(const Value * V,unsigned InstID,SmallVector<unsigned,64> & Vals,llvm_2_9::ValueEnumerator & VE)1049 static bool PushValueAndType(const Value *V, unsigned InstID,
1050                              SmallVector<unsigned, 64> &Vals,
1051                              llvm_2_9::ValueEnumerator &VE) {
1052   unsigned ValID = VE.getValueID(V);
1053   Vals.push_back(ValID);
1054   if (ValID >= InstID) {
1055     Vals.push_back(VE.getTypeID(V->getType()));
1056     return true;
1057   }
1058   return false;
1059 }
1060 
1061 /// WriteInstruction - Emit an instruction to the specified stream.
WriteInstruction(const Instruction & I,unsigned InstID,llvm_2_9::ValueEnumerator & VE,BitstreamWriter & Stream,SmallVector<unsigned,64> & Vals)1062 static void WriteInstruction(const Instruction &I, unsigned InstID,
1063                              llvm_2_9::ValueEnumerator &VE,
1064                              BitstreamWriter &Stream,
1065                              SmallVector<unsigned, 64> &Vals) {
1066   unsigned Code = 0;
1067   unsigned AbbrevToUse = 0;
1068   VE.setInstructionID(&I);
1069   switch (I.getOpcode()) {
1070   default:
1071     if (Instruction::isCast(I.getOpcode())) {
1072       Code = bitc::FUNC_CODE_INST_CAST;
1073       if (!PushValueAndType(I.getOperand(0), InstID, Vals, VE))
1074         AbbrevToUse = FUNCTION_INST_CAST_ABBREV;
1075       Vals.push_back(VE.getTypeID(I.getType()));
1076       Vals.push_back(GetEncodedCastOpcode(I.getOpcode()));
1077     } else {
1078       assert(isa<BinaryOperator>(I) && "Unknown instruction!");
1079       Code = bitc::FUNC_CODE_INST_BINOP;
1080       if (!PushValueAndType(I.getOperand(0), InstID, Vals, VE))
1081         AbbrevToUse = FUNCTION_INST_BINOP_ABBREV;
1082       Vals.push_back(VE.getValueID(I.getOperand(1)));
1083       Vals.push_back(GetEncodedBinaryOpcode(I.getOpcode()));
1084       uint64_t Flags = GetOptimizationFlags(&I);
1085       if (Flags != 0) {
1086         if (AbbrevToUse == FUNCTION_INST_BINOP_ABBREV)
1087           AbbrevToUse = FUNCTION_INST_BINOP_FLAGS_ABBREV;
1088         Vals.push_back(Flags);
1089       }
1090     }
1091     break;
1092 
1093   case Instruction::GetElementPtr:
1094     Code = bitc::FUNC_CODE_INST_GEP_OLD;
1095     if (cast<GEPOperator>(&I)->isInBounds())
1096       Code = bitc::FUNC_CODE_INST_INBOUNDS_GEP_OLD;
1097     for (unsigned i = 0, e = I.getNumOperands(); i != e; ++i)
1098       PushValueAndType(I.getOperand(i), InstID, Vals, VE);
1099     break;
1100   case Instruction::ExtractValue: {
1101     Code = bitc::FUNC_CODE_INST_EXTRACTVAL;
1102     PushValueAndType(I.getOperand(0), InstID, Vals, VE);
1103     const ExtractValueInst *EVI = cast<ExtractValueInst>(&I);
1104     for (const unsigned *i = EVI->idx_begin(), *e = EVI->idx_end(); i != e; ++i)
1105       Vals.push_back(*i);
1106     break;
1107   }
1108   case Instruction::InsertValue: {
1109     Code = bitc::FUNC_CODE_INST_INSERTVAL;
1110     PushValueAndType(I.getOperand(0), InstID, Vals, VE);
1111     PushValueAndType(I.getOperand(1), InstID, Vals, VE);
1112     const InsertValueInst *IVI = cast<InsertValueInst>(&I);
1113     for (const unsigned *i = IVI->idx_begin(), *e = IVI->idx_end(); i != e; ++i)
1114       Vals.push_back(*i);
1115     break;
1116   }
1117   case Instruction::Select:
1118     Code = bitc::FUNC_CODE_INST_VSELECT;
1119     PushValueAndType(I.getOperand(1), InstID, Vals, VE);
1120     Vals.push_back(VE.getValueID(I.getOperand(2)));
1121     PushValueAndType(I.getOperand(0), InstID, Vals, VE);
1122     break;
1123   case Instruction::ExtractElement:
1124     Code = bitc::FUNC_CODE_INST_EXTRACTELT;
1125     PushValueAndType(I.getOperand(0), InstID, Vals, VE);
1126     Vals.push_back(VE.getValueID(I.getOperand(1)));
1127     break;
1128   case Instruction::InsertElement:
1129     Code = bitc::FUNC_CODE_INST_INSERTELT;
1130     PushValueAndType(I.getOperand(0), InstID, Vals, VE);
1131     Vals.push_back(VE.getValueID(I.getOperand(1)));
1132     Vals.push_back(VE.getValueID(I.getOperand(2)));
1133     break;
1134   case Instruction::ShuffleVector:
1135     Code = bitc::FUNC_CODE_INST_SHUFFLEVEC;
1136     PushValueAndType(I.getOperand(0), InstID, Vals, VE);
1137     Vals.push_back(VE.getValueID(I.getOperand(1)));
1138     Vals.push_back(VE.getValueID(I.getOperand(2)));
1139     break;
1140   case Instruction::ICmp:
1141   case Instruction::FCmp:
1142     // compare returning Int1Ty or vector of Int1Ty
1143     Code = bitc::FUNC_CODE_INST_CMP2;
1144     PushValueAndType(I.getOperand(0), InstID, Vals, VE);
1145     Vals.push_back(VE.getValueID(I.getOperand(1)));
1146     Vals.push_back(cast<CmpInst>(I).getPredicate());
1147     break;
1148 
1149   case Instruction::Ret:
1150     {
1151       Code = bitc::FUNC_CODE_INST_RET;
1152       unsigned NumOperands = I.getNumOperands();
1153       if (NumOperands == 0)
1154         AbbrevToUse = FUNCTION_INST_RET_VOID_ABBREV;
1155       else if (NumOperands == 1) {
1156         if (!PushValueAndType(I.getOperand(0), InstID, Vals, VE))
1157           AbbrevToUse = FUNCTION_INST_RET_VAL_ABBREV;
1158       } else {
1159         for (unsigned i = 0, e = NumOperands; i != e; ++i)
1160           PushValueAndType(I.getOperand(i), InstID, Vals, VE);
1161       }
1162     }
1163     break;
1164   case Instruction::Br:
1165     {
1166       Code = bitc::FUNC_CODE_INST_BR;
1167       const BranchInst &II = cast<BranchInst>(I);
1168       Vals.push_back(VE.getValueID(II.getSuccessor(0)));
1169       if (II.isConditional()) {
1170         Vals.push_back(VE.getValueID(II.getSuccessor(1)));
1171         Vals.push_back(VE.getValueID(II.getCondition()));
1172       }
1173     }
1174     break;
1175   case Instruction::Switch:
1176     {
1177       Code = bitc::FUNC_CODE_INST_SWITCH;
1178       const SwitchInst &SI = cast<SwitchInst>(I);
1179       Vals.push_back(VE.getTypeID(SI.getCondition()->getType()));
1180       Vals.push_back(VE.getValueID(SI.getCondition()));
1181       Vals.push_back(VE.getValueID(SI.getDefaultDest()));
1182       for (SwitchInst::ConstCaseIt i = SI.case_begin(), e = SI.case_end();
1183            i != e; ++i) {
1184         Vals.push_back(VE.getValueID(i.getCaseValue()));
1185         Vals.push_back(VE.getValueID(i.getCaseSuccessor()));
1186       }
1187     }
1188     break;
1189   case Instruction::IndirectBr:
1190     Code = bitc::FUNC_CODE_INST_INDIRECTBR;
1191     Vals.push_back(VE.getTypeID(I.getOperand(0)->getType()));
1192     for (unsigned i = 0, e = I.getNumOperands(); i != e; ++i)
1193       Vals.push_back(VE.getValueID(I.getOperand(i)));
1194     break;
1195 
1196   case Instruction::Invoke: {
1197     const InvokeInst *II = cast<InvokeInst>(&I);
1198     const Value *Callee(II->getCalledValue());
1199     PointerType *PTy = cast<PointerType>(Callee->getType());
1200     FunctionType *FTy = cast<FunctionType>(PTy->getElementType());
1201     Code = bitc::FUNC_CODE_INST_INVOKE;
1202 
1203     Vals.push_back(VE.getAttributeID(II->getAttributes()));
1204     Vals.push_back(II->getCallingConv());
1205     Vals.push_back(VE.getValueID(II->getNormalDest()));
1206     Vals.push_back(VE.getValueID(II->getUnwindDest()));
1207     PushValueAndType(Callee, InstID, Vals, VE);
1208 
1209     // Emit value #'s for the fixed parameters.
1210     for (unsigned i = 0, e = FTy->getNumParams(); i != e; ++i)
1211       Vals.push_back(VE.getValueID(I.getOperand(i)));  // fixed param.
1212 
1213     // Emit type/value pairs for varargs params.
1214     if (FTy->isVarArg()) {
1215       for (unsigned i = FTy->getNumParams(), e = I.getNumOperands()-3;
1216            i != e; ++i)
1217         PushValueAndType(I.getOperand(i), InstID, Vals, VE); // vararg
1218     }
1219     break;
1220   }
1221   case Instruction::Unreachable:
1222     Code = bitc::FUNC_CODE_INST_UNREACHABLE;
1223     AbbrevToUse = FUNCTION_INST_UNREACHABLE_ABBREV;
1224     break;
1225 
1226   case Instruction::PHI: {
1227     const PHINode &PN = cast<PHINode>(I);
1228     Code = bitc::FUNC_CODE_INST_PHI;
1229     Vals.push_back(VE.getTypeID(PN.getType()));
1230     for (unsigned i = 0, e = PN.getNumIncomingValues(); i != e; ++i) {
1231       Vals.push_back(VE.getValueID(PN.getIncomingValue(i)));
1232       Vals.push_back(VE.getValueID(PN.getIncomingBlock(i)));
1233     }
1234     break;
1235   }
1236 
1237   case Instruction::Alloca:
1238     Code = bitc::FUNC_CODE_INST_ALLOCA;
1239     Vals.push_back(VE.getTypeID(I.getType()));
1240     Vals.push_back(VE.getTypeID(I.getOperand(0)->getType()));
1241     Vals.push_back(VE.getValueID(I.getOperand(0))); // size.
1242     Vals.push_back(Log2_32(cast<AllocaInst>(I).getAlignment())+1);
1243     break;
1244 
1245   case Instruction::Load:
1246     Code = bitc::FUNC_CODE_INST_LOAD;
1247     if (!PushValueAndType(I.getOperand(0), InstID, Vals, VE))  // ptr
1248       AbbrevToUse = FUNCTION_INST_LOAD_ABBREV;
1249 
1250     Vals.push_back(Log2_32(cast<LoadInst>(I).getAlignment())+1);
1251     Vals.push_back(cast<LoadInst>(I).isVolatile());
1252     break;
1253   case Instruction::Store:
1254     Code = bitc::FUNC_CODE_INST_STORE_OLD;
1255     PushValueAndType(I.getOperand(1), InstID, Vals, VE);  // ptrty + ptr
1256     Vals.push_back(VE.getValueID(I.getOperand(0)));       // val.
1257     Vals.push_back(Log2_32(cast<StoreInst>(I).getAlignment())+1);
1258     Vals.push_back(cast<StoreInst>(I).isVolatile());
1259     break;
1260   case Instruction::Call: {
1261     const CallInst &CI = cast<CallInst>(I);
1262     PointerType *PTy = cast<PointerType>(CI.getCalledValue()->getType());
1263     FunctionType *FTy = cast<FunctionType>(PTy->getElementType());
1264 
1265     Code = FUNC_CODE_INST_CALL_2_7;
1266 
1267     Vals.push_back(VE.getAttributeID(CI.getAttributes()));
1268     Vals.push_back((CI.getCallingConv() << 1) | unsigned(CI.isTailCall()));
1269     PushValueAndType(CI.getCalledValue(), InstID, Vals, VE);  // Callee
1270 
1271     // Emit value #'s for the fixed parameters.
1272     for (unsigned i = 0, e = FTy->getNumParams(); i != e; ++i)
1273       Vals.push_back(VE.getValueID(CI.getArgOperand(i)));  // fixed param.
1274 
1275     // Emit type/value pairs for varargs params.
1276     if (FTy->isVarArg()) {
1277       for (unsigned i = FTy->getNumParams(), e = CI.getNumArgOperands();
1278            i != e; ++i)
1279         PushValueAndType(CI.getArgOperand(i), InstID, Vals, VE);  // varargs
1280     }
1281     break;
1282   }
1283   case Instruction::VAArg:
1284     Code = bitc::FUNC_CODE_INST_VAARG;
1285     Vals.push_back(VE.getTypeID(I.getOperand(0)->getType()));   // valistty
1286     Vals.push_back(VE.getValueID(I.getOperand(0))); // valist.
1287     Vals.push_back(VE.getTypeID(I.getType())); // restype.
1288     break;
1289   }
1290 
1291   Stream.EmitRecord(Code, Vals, AbbrevToUse);
1292   Vals.clear();
1293 }
1294 
1295 // Emit names for globals/functions etc.
WriteValueSymbolTable(const ValueSymbolTable & VST,const llvm_2_9::ValueEnumerator & VE,BitstreamWriter & Stream)1296 static void WriteValueSymbolTable(const ValueSymbolTable &VST,
1297                                   const llvm_2_9::ValueEnumerator &VE,
1298                                   BitstreamWriter &Stream) {
1299   if (VST.empty()) return;
1300   Stream.EnterSubblock(bitc::VALUE_SYMTAB_BLOCK_ID, 4);
1301 
1302   // FIXME: Set up the abbrev, we know how many values there are!
1303   // FIXME: We know if the type names can use 7-bit ascii.
1304   SmallVector<unsigned, 64> NameVals;
1305 
1306   for (ValueSymbolTable::const_iterator SI = VST.begin(), SE = VST.end();
1307        SI != SE; ++SI) {
1308 
1309     const ValueName &Name = *SI;
1310 
1311     // Figure out the encoding to use for the name.
1312     bool is7Bit = true;
1313     bool isChar6 = true;
1314     for (const char *C = Name.getKeyData(), *E = C+Name.getKeyLength();
1315          C != E; ++C) {
1316       if (isChar6)
1317         isChar6 = BitCodeAbbrevOp::isChar6(*C);
1318       if ((unsigned char)*C & 128) {
1319         is7Bit = false;
1320         break;  // don't bother scanning the rest.
1321       }
1322     }
1323 
1324     unsigned AbbrevToUse = VST_ENTRY_8_ABBREV;
1325 
1326     // VST_ENTRY:   [valueid, namechar x N]
1327     // VST_BBENTRY: [bbid, namechar x N]
1328     unsigned Code;
1329     if (isa<BasicBlock>(SI->getValue())) {
1330       Code = bitc::VST_CODE_BBENTRY;
1331       if (isChar6)
1332         AbbrevToUse = VST_BBENTRY_6_ABBREV;
1333     } else {
1334       Code = bitc::VST_CODE_ENTRY;
1335       if (isChar6)
1336         AbbrevToUse = VST_ENTRY_6_ABBREV;
1337       else if (is7Bit)
1338         AbbrevToUse = VST_ENTRY_7_ABBREV;
1339     }
1340 
1341     NameVals.push_back(VE.getValueID(SI->getValue()));
1342     for (const char *P = Name.getKeyData(),
1343          *E = Name.getKeyData()+Name.getKeyLength(); P != E; ++P)
1344       NameVals.push_back((unsigned char)*P);
1345 
1346     // Emit the finished record.
1347     Stream.EmitRecord(Code, NameVals, AbbrevToUse);
1348     NameVals.clear();
1349   }
1350   Stream.ExitBlock();
1351 }
1352 
1353 /// WriteFunction - Emit a function body to the module stream.
WriteFunction(const Function & F,llvm_2_9::ValueEnumerator & VE,BitstreamWriter & Stream)1354 static void WriteFunction(const Function &F, llvm_2_9::ValueEnumerator &VE,
1355                           BitstreamWriter &Stream) {
1356   Stream.EnterSubblock(bitc::FUNCTION_BLOCK_ID, 4);
1357   VE.incorporateFunction(F);
1358 
1359   SmallVector<unsigned, 64> Vals;
1360 
1361   // Emit the number of basic blocks, so the reader can create them ahead of
1362   // time.
1363   Vals.push_back(VE.getBasicBlocks().size());
1364   Stream.EmitRecord(bitc::FUNC_CODE_DECLAREBLOCKS, Vals);
1365   Vals.clear();
1366 
1367   // If there are function-local constants, emit them now.
1368   unsigned CstStart, CstEnd;
1369   VE.getFunctionConstantRange(CstStart, CstEnd);
1370   WriteConstants(CstStart, CstEnd, VE, Stream, false);
1371 
1372   // If there is function-local metadata, emit it now.
1373   WriteFunctionLocalMetadata(F, VE, Stream);
1374 
1375   // Keep a running idea of what the instruction ID is.
1376   unsigned InstID = CstEnd;
1377 
1378   bool NeedsMetadataAttachment = false;
1379 
1380   DILocation *LastDL = nullptr;;
1381 
1382   // Finally, emit all the instructions, in order.
1383   for (Function::const_iterator BB = F.begin(), E = F.end(); BB != E; ++BB)
1384     for (BasicBlock::const_iterator I = BB->begin(), E = BB->end();
1385          I != E; ++I) {
1386       WriteInstruction(*I, InstID, VE, Stream, Vals);
1387 
1388       if (!I->getType()->isVoidTy())
1389         ++InstID;
1390 
1391       // If the instruction has metadata, write a metadata attachment later.
1392       NeedsMetadataAttachment |= I->hasMetadataOtherThanDebugLoc();
1393 
1394       // If the instruction has a debug location, emit it.
1395       DILocation *DL = I->getDebugLoc();
1396       if (!DL)
1397         continue;
1398 
1399       if (DL == LastDL) {
1400         // Just repeat the same debug loc as last time.
1401         Stream.EmitRecord(bitc::FUNC_CODE_DEBUG_LOC_AGAIN, Vals);
1402         continue;
1403       }
1404 
1405       Vals.push_back(DL->getLine());
1406       Vals.push_back(DL->getColumn());
1407       Vals.push_back(VE.getMetadataOrNullID(DL->getScope()));
1408       Vals.push_back(VE.getMetadataOrNullID(DL->getInlinedAt()));
1409       Stream.EmitRecord(FUNC_CODE_DEBUG_LOC_2_7, Vals);
1410       Vals.clear();
1411 
1412       LastDL = DL;
1413     }
1414 
1415   // Emit names for all the instructions etc.
1416   WriteValueSymbolTable(F.getValueSymbolTable(), VE, Stream);
1417 
1418   if (NeedsMetadataAttachment)
1419     WriteMetadataAttachment(F, VE, Stream);
1420   VE.purgeFunction();
1421   Stream.ExitBlock();
1422 }
1423 
1424 // Emit blockinfo, which defines the standard abbreviations etc.
WriteBlockInfo(const llvm_2_9::ValueEnumerator & VE,BitstreamWriter & Stream)1425 static void WriteBlockInfo(const llvm_2_9::ValueEnumerator &VE,
1426                            BitstreamWriter &Stream) {
1427   // We only want to emit block info records for blocks that have multiple
1428   // instances: CONSTANTS_BLOCK, FUNCTION_BLOCK and VALUE_SYMTAB_BLOCK.  Other
1429   // blocks can defined their abbrevs inline.
1430   Stream.EnterBlockInfoBlock(2);
1431 
1432   { // 8-bit fixed-width VST_ENTRY/VST_BBENTRY strings.
1433     BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1434     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3));
1435     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
1436     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1437     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 8));
1438     if (Stream.EmitBlockInfoAbbrev(bitc::VALUE_SYMTAB_BLOCK_ID,
1439                                    Abbv) != VST_ENTRY_8_ABBREV)
1440       llvm_unreachable("Unexpected abbrev ordering!");
1441   }
1442 
1443   { // 7-bit fixed width VST_ENTRY strings.
1444     BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1445     Abbv->Add(BitCodeAbbrevOp(bitc::VST_CODE_ENTRY));
1446     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
1447     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1448     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 7));
1449     if (Stream.EmitBlockInfoAbbrev(bitc::VALUE_SYMTAB_BLOCK_ID,
1450                                    Abbv) != VST_ENTRY_7_ABBREV)
1451       llvm_unreachable("Unexpected abbrev ordering!");
1452   }
1453   { // 6-bit char6 VST_ENTRY strings.
1454     BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1455     Abbv->Add(BitCodeAbbrevOp(bitc::VST_CODE_ENTRY));
1456     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
1457     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1458     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Char6));
1459     if (Stream.EmitBlockInfoAbbrev(bitc::VALUE_SYMTAB_BLOCK_ID,
1460                                    Abbv) != VST_ENTRY_6_ABBREV)
1461       llvm_unreachable("Unexpected abbrev ordering!");
1462   }
1463   { // 6-bit char6 VST_BBENTRY strings.
1464     BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1465     Abbv->Add(BitCodeAbbrevOp(bitc::VST_CODE_BBENTRY));
1466     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
1467     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1468     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Char6));
1469     if (Stream.EmitBlockInfoAbbrev(bitc::VALUE_SYMTAB_BLOCK_ID,
1470                                    Abbv) != VST_BBENTRY_6_ABBREV)
1471       llvm_unreachable("Unexpected abbrev ordering!");
1472   }
1473 
1474 
1475 
1476   { // SETTYPE abbrev for CONSTANTS_BLOCK.
1477     BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1478     Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_SETTYPE));
1479     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
1480                               Log2_32_Ceil(VE.getTypes().size()+1)));
1481     if (Stream.EmitBlockInfoAbbrev(bitc::CONSTANTS_BLOCK_ID,
1482                                    Abbv) != CONSTANTS_SETTYPE_ABBREV)
1483       llvm_unreachable("Unexpected abbrev ordering!");
1484   }
1485 
1486   { // INTEGER abbrev for CONSTANTS_BLOCK.
1487     BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1488     Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_INTEGER));
1489     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
1490     if (Stream.EmitBlockInfoAbbrev(bitc::CONSTANTS_BLOCK_ID,
1491                                    Abbv) != CONSTANTS_INTEGER_ABBREV)
1492       llvm_unreachable("Unexpected abbrev ordering!");
1493   }
1494 
1495   { // CE_CAST abbrev for CONSTANTS_BLOCK.
1496     BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1497     Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_CE_CAST));
1498     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 4));  // cast opc
1499     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,       // typeid
1500                               Log2_32_Ceil(VE.getTypes().size()+1)));
1501     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));    // value id
1502 
1503     if (Stream.EmitBlockInfoAbbrev(bitc::CONSTANTS_BLOCK_ID,
1504                                    Abbv) != CONSTANTS_CE_CAST_Abbrev)
1505       llvm_unreachable("Unexpected abbrev ordering!");
1506   }
1507   { // NULL abbrev for CONSTANTS_BLOCK.
1508     BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1509     Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_NULL));
1510     if (Stream.EmitBlockInfoAbbrev(bitc::CONSTANTS_BLOCK_ID,
1511                                    Abbv) != CONSTANTS_NULL_Abbrev)
1512       llvm_unreachable("Unexpected abbrev ordering!");
1513   }
1514 
1515   // FIXME: This should only use space for first class types!
1516 
1517   { // INST_LOAD abbrev for FUNCTION_BLOCK.
1518     BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1519     Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_LOAD));
1520     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Ptr
1521     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 4)); // Align
1522     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // volatile
1523     if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID,
1524                                    Abbv) != FUNCTION_INST_LOAD_ABBREV)
1525       llvm_unreachable("Unexpected abbrev ordering!");
1526   }
1527   { // INST_BINOP abbrev for FUNCTION_BLOCK.
1528     BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1529     Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_BINOP));
1530     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // LHS
1531     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // RHS
1532     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 4)); // opc
1533     if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID,
1534                                    Abbv) != FUNCTION_INST_BINOP_ABBREV)
1535       llvm_unreachable("Unexpected abbrev ordering!");
1536   }
1537   { // INST_BINOP_FLAGS abbrev for FUNCTION_BLOCK.
1538     BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1539     Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_BINOP));
1540     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // LHS
1541     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // RHS
1542     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 4)); // opc
1543     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 7)); // flags
1544     if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID,
1545                                    Abbv) != FUNCTION_INST_BINOP_FLAGS_ABBREV)
1546       llvm_unreachable("Unexpected abbrev ordering!");
1547   }
1548   { // INST_CAST abbrev for FUNCTION_BLOCK.
1549     BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1550     Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_CAST));
1551     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));    // OpVal
1552     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,       // dest ty
1553                               Log2_32_Ceil(VE.getTypes().size()+1)));
1554     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 4));  // opc
1555     if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID,
1556                                    Abbv) != FUNCTION_INST_CAST_ABBREV)
1557       llvm_unreachable("Unexpected abbrev ordering!");
1558   }
1559 
1560   { // INST_RET abbrev for FUNCTION_BLOCK.
1561     BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1562     Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_RET));
1563     if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID,
1564                                    Abbv) != FUNCTION_INST_RET_VOID_ABBREV)
1565       llvm_unreachable("Unexpected abbrev ordering!");
1566   }
1567   { // INST_RET abbrev for FUNCTION_BLOCK.
1568     BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1569     Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_RET));
1570     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // ValID
1571     if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID,
1572                                    Abbv) != FUNCTION_INST_RET_VAL_ABBREV)
1573       llvm_unreachable("Unexpected abbrev ordering!");
1574   }
1575   { // INST_UNREACHABLE abbrev for FUNCTION_BLOCK.
1576     BitCodeAbbrev *Abbv = new BitCodeAbbrev();
1577     Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_UNREACHABLE));
1578     if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID,
1579                                    Abbv) != FUNCTION_INST_UNREACHABLE_ABBREV)
1580       llvm_unreachable("Unexpected abbrev ordering!");
1581   }
1582 
1583   Stream.ExitBlock();
1584 }
1585 
1586 /// WriteModule - Emit the specified module to the bitstream.
WriteModule(const Module * M,BitstreamWriter & Stream)1587 static void WriteModule(const Module *M, BitstreamWriter &Stream) {
1588   Stream.EnterSubblock(bitc::MODULE_BLOCK_ID, 3);
1589 
1590   // Emit the version number if it is non-zero.
1591   if (CurVersion) {
1592     SmallVector<unsigned, 1> Vals;
1593     Vals.push_back(CurVersion);
1594     Stream.EmitRecord(bitc::MODULE_CODE_VERSION, Vals);
1595   }
1596 
1597   // Analyze the module, enumerating globals, functions, etc.
1598   llvm_2_9::ValueEnumerator VE(*M);
1599 
1600   // Emit blockinfo, which defines the standard abbreviations etc.
1601   WriteBlockInfo(VE, Stream);
1602 
1603   // Emit information about parameter attributes.
1604   WriteAttributeTable(VE, Stream);
1605 
1606   // Emit information describing all of the types in the module.
1607   WriteTypeTable(VE, Stream);
1608 
1609   // Emit top-level description of module, including target triple, inline asm,
1610   // descriptors for global variables, and function prototype info.
1611   WriteModuleInfo(M, VE, Stream);
1612 
1613   // Emit constants.
1614   WriteModuleConstants(VE, Stream);
1615 
1616   // Emit metadata.
1617   WriteModuleMetadata(M, VE, Stream);
1618 
1619   // Emit function bodies.
1620   for (Module::const_iterator F = M->begin(), E = M->end(); F != E; ++F)
1621     if (!F->isDeclaration())
1622       WriteFunction(*F, VE, Stream);
1623 
1624   // Emit metadata.
1625   WriteModuleMetadataStore(M, Stream);
1626 
1627   // Emit names for globals/functions etc.
1628   WriteValueSymbolTable(M->getValueSymbolTable(), VE, Stream);
1629 
1630   Stream.ExitBlock();
1631 }
1632 
1633 /// EmitDarwinBCHeader - If generating a bc file on darwin, we have to emit a
1634 /// header and trailer to make it compatible with the system archiver.  To do
1635 /// this we emit the following header, and then emit a trailer that pads the
1636 /// file out to be a multiple of 16 bytes.
1637 ///
1638 /// struct bc_header {
1639 ///   uint32_t Magic;         // 0x0B17C0DE
1640 ///   uint32_t Version;       // Version, currently always 0.
1641 ///   uint32_t BitcodeOffset; // Offset to traditional bitcode file.
1642 ///   uint32_t BitcodeSize;   // Size of traditional bitcode file.
1643 ///   uint32_t CPUType;       // CPU specifier.
1644 ///   ... potentially more later ...
1645 /// };
1646 enum {
1647   DarwinBCSizeFieldOffset = 3*4, // Offset to bitcode_size.
1648   DarwinBCHeaderSize = 5*4
1649 };
1650 
WriteInt32ToBuffer(uint32_t Value,SmallVectorImpl<char> & Buffer,uint32_t & Position)1651 static void WriteInt32ToBuffer(uint32_t Value, SmallVectorImpl<char> &Buffer,
1652                                uint32_t &Position) {
1653   Buffer[Position + 0] = (unsigned char) (Value >>  0);
1654   Buffer[Position + 1] = (unsigned char) (Value >>  8);
1655   Buffer[Position + 2] = (unsigned char) (Value >> 16);
1656   Buffer[Position + 3] = (unsigned char) (Value >> 24);
1657   Position += 4;
1658 }
1659 
EmitDarwinBCHeaderAndTrailer(SmallVectorImpl<char> & Buffer,const Triple & TT)1660 static void EmitDarwinBCHeaderAndTrailer(SmallVectorImpl<char> &Buffer,
1661                                          const Triple &TT) {
1662   unsigned CPUType = ~0U;
1663 
1664   // Match x86_64-*, i[3-9]86-*, powerpc-*, powerpc64-*, arm-*, thumb-*,
1665   // armv[0-9]-*, thumbv[0-9]-*, armv5te-*, or armv6t2-*. The CPUType is a magic
1666   // number from /usr/include/mach/machine.h.  It is ok to reproduce the
1667   // specific constants here because they are implicitly part of the Darwin ABI.
1668   enum {
1669     DARWIN_CPU_ARCH_ABI64      = 0x01000000,
1670     DARWIN_CPU_TYPE_X86        = 7,
1671     DARWIN_CPU_TYPE_ARM        = 12,
1672     DARWIN_CPU_TYPE_POWERPC    = 18
1673   };
1674 
1675   Triple::ArchType Arch = TT.getArch();
1676   if (Arch == Triple::x86_64)
1677     CPUType = DARWIN_CPU_TYPE_X86 | DARWIN_CPU_ARCH_ABI64;
1678   else if (Arch == Triple::x86)
1679     CPUType = DARWIN_CPU_TYPE_X86;
1680   else if (Arch == Triple::ppc)
1681     CPUType = DARWIN_CPU_TYPE_POWERPC;
1682   else if (Arch == Triple::ppc64)
1683     CPUType = DARWIN_CPU_TYPE_POWERPC | DARWIN_CPU_ARCH_ABI64;
1684   else if (Arch == Triple::arm || Arch == Triple::thumb)
1685     CPUType = DARWIN_CPU_TYPE_ARM;
1686 
1687   // Traditional Bitcode starts after header.
1688   assert(Buffer.size() >= DarwinBCHeaderSize &&
1689          "Expected header size to be reserved");
1690   unsigned BCOffset = DarwinBCHeaderSize;
1691   unsigned BCSize = Buffer.size()-DarwinBCHeaderSize;
1692 
1693   // Write the magic and version.
1694   unsigned Position = 0;
1695   WriteInt32ToBuffer(0x0B17C0DE , Buffer, Position);
1696   WriteInt32ToBuffer(0          , Buffer, Position); // Version.
1697   WriteInt32ToBuffer(BCOffset   , Buffer, Position);
1698   WriteInt32ToBuffer(BCSize     , Buffer, Position);
1699   WriteInt32ToBuffer(CPUType    , Buffer, Position);
1700 
1701   // If the file is not a multiple of 16 bytes, insert dummy padding.
1702   while (Buffer.size() & 15)
1703     Buffer.push_back(0);
1704 }
1705 
1706 /// WriteBitcodeToFile - Write the specified module to the specified output
1707 /// stream.
WriteBitcodeToFile(const Module * M,raw_ostream & Out)1708 void llvm_2_9::WriteBitcodeToFile(const Module *M, raw_ostream &Out) {
1709   SmallVector<char, 1024> Buffer;
1710   Buffer.reserve(256*1024);
1711 
1712   // If this is darwin or another generic macho target, reserve space for the
1713   // header.
1714   Triple TT(M->getTargetTriple());
1715   if (TT.isOSDarwin())
1716     Buffer.insert(Buffer.begin(), DarwinBCHeaderSize, 0);
1717 
1718   // Emit the module into the buffer.
1719   {
1720     BitstreamWriter Stream(Buffer);
1721 
1722     // Emit the file header.
1723     Stream.Emit((unsigned)'B', 8);
1724     Stream.Emit((unsigned)'C', 8);
1725     Stream.Emit(0x0, 4);
1726     Stream.Emit(0xC, 4);
1727     Stream.Emit(0xE, 4);
1728     Stream.Emit(0xD, 4);
1729 
1730     // Emit the module.
1731     WriteModule(M, Stream);
1732   }
1733 
1734   if (TT.isOSDarwin())
1735     EmitDarwinBCHeaderAndTrailer(Buffer, TT);
1736 
1737   // Write the generated bitstream to "Out".
1738   Out.write((char*)&Buffer.front(), Buffer.size());
1739 }
1740