xref: /llvm-project/llvm/lib/Target/DirectX/DXILWriter/DXILBitcodeWriter.cpp (revision 26129766df701d462ed9a6a9a68a88b3564a70bd)
1 //===- Bitcode/Writer/DXILBitcodeWriter.cpp - DXIL Bitcode Writer ---------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // Bitcode writer implementation.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #include "DXILBitcodeWriter.h"
14 #include "DXILValueEnumerator.h"
15 #include "PointerTypeAnalysis.h"
16 #include "llvm/ADT/STLExtras.h"
17 #include "llvm/ADT/Triple.h"
18 #include "llvm/Bitcode/BitcodeCommon.h"
19 #include "llvm/Bitcode/BitcodeReader.h"
20 #include "llvm/Bitcode/LLVMBitCodes.h"
21 #include "llvm/Bitstream/BitCodes.h"
22 #include "llvm/Bitstream/BitstreamWriter.h"
23 #include "llvm/IR/Attributes.h"
24 #include "llvm/IR/BasicBlock.h"
25 #include "llvm/IR/Comdat.h"
26 #include "llvm/IR/Constant.h"
27 #include "llvm/IR/Constants.h"
28 #include "llvm/IR/DebugInfoMetadata.h"
29 #include "llvm/IR/DebugLoc.h"
30 #include "llvm/IR/DerivedTypes.h"
31 #include "llvm/IR/Function.h"
32 #include "llvm/IR/GlobalAlias.h"
33 #include "llvm/IR/GlobalIFunc.h"
34 #include "llvm/IR/GlobalObject.h"
35 #include "llvm/IR/GlobalValue.h"
36 #include "llvm/IR/GlobalVariable.h"
37 #include "llvm/IR/InlineAsm.h"
38 #include "llvm/IR/InstrTypes.h"
39 #include "llvm/IR/Instruction.h"
40 #include "llvm/IR/Instructions.h"
41 #include "llvm/IR/LLVMContext.h"
42 #include "llvm/IR/Metadata.h"
43 #include "llvm/IR/Module.h"
44 #include "llvm/IR/ModuleSummaryIndex.h"
45 #include "llvm/IR/Operator.h"
46 #include "llvm/IR/Type.h"
47 #include "llvm/IR/UseListOrder.h"
48 #include "llvm/IR/Value.h"
49 #include "llvm/IR/ValueSymbolTable.h"
50 #include "llvm/Object/IRSymtab.h"
51 #include "llvm/Support/ErrorHandling.h"
52 #include "llvm/Support/SHA1.h"
53 
54 namespace llvm {
55 namespace dxil {
56 
57 // Generates an enum to use as an index in the Abbrev array of Metadata record.
58 enum MetadataAbbrev : unsigned {
59 #define HANDLE_MDNODE_LEAF(CLASS) CLASS##AbbrevID,
60 #include "llvm/IR/Metadata.def"
61   LastPlusOne
62 };
63 
64 class DXILBitcodeWriter {
65 
66   /// These are manifest constants used by the bitcode writer. They do not need
67   /// to be kept in sync with the reader, but need to be consistent within this
68   /// file.
69   enum {
70     // VALUE_SYMTAB_BLOCK abbrev id's.
71     VST_ENTRY_8_ABBREV = bitc::FIRST_APPLICATION_ABBREV,
72     VST_ENTRY_7_ABBREV,
73     VST_ENTRY_6_ABBREV,
74     VST_BBENTRY_6_ABBREV,
75 
76     // CONSTANTS_BLOCK abbrev id's.
77     CONSTANTS_SETTYPE_ABBREV = bitc::FIRST_APPLICATION_ABBREV,
78     CONSTANTS_INTEGER_ABBREV,
79     CONSTANTS_CE_CAST_Abbrev,
80     CONSTANTS_NULL_Abbrev,
81 
82     // FUNCTION_BLOCK abbrev id's.
83     FUNCTION_INST_LOAD_ABBREV = bitc::FIRST_APPLICATION_ABBREV,
84     FUNCTION_INST_BINOP_ABBREV,
85     FUNCTION_INST_BINOP_FLAGS_ABBREV,
86     FUNCTION_INST_CAST_ABBREV,
87     FUNCTION_INST_RET_VOID_ABBREV,
88     FUNCTION_INST_RET_VAL_ABBREV,
89     FUNCTION_INST_UNREACHABLE_ABBREV,
90     FUNCTION_INST_GEP_ABBREV,
91   };
92 
93   // Cache some types
94   Type *I8Ty;
95   Type *I8PtrTy;
96 
97   /// The stream created and owned by the client.
98   BitstreamWriter &Stream;
99 
100   StringTableBuilder &StrtabBuilder;
101 
102   /// The Module to write to bitcode.
103   const Module &M;
104 
105   /// Enumerates ids for all values in the module.
106   ValueEnumerator VE;
107 
108   /// Map that holds the correspondence between GUIDs in the summary index,
109   /// that came from indirect call profiles, and a value id generated by this
110   /// class to use in the VST and summary block records.
111   std::map<GlobalValue::GUID, unsigned> GUIDToValueIdMap;
112 
113   /// Tracks the last value id recorded in the GUIDToValueMap.
114   unsigned GlobalValueId;
115 
116   /// Saves the offset of the VSTOffset record that must eventually be
117   /// backpatched with the offset of the actual VST.
118   uint64_t VSTOffsetPlaceholder = 0;
119 
120   /// Pointer to the buffer allocated by caller for bitcode writing.
121   const SmallVectorImpl<char> &Buffer;
122 
123   /// The start bit of the identification block.
124   uint64_t BitcodeStartBit;
125 
126   /// This maps values to their typed pointers
127   PointerTypeMap PointerMap;
128 
129 public:
130   /// Constructs a ModuleBitcodeWriter object for the given Module,
131   /// writing to the provided \p Buffer.
132   DXILBitcodeWriter(const Module &M, SmallVectorImpl<char> &Buffer,
133                     StringTableBuilder &StrtabBuilder, BitstreamWriter &Stream)
134       : I8Ty(Type::getInt8Ty(M.getContext())),
135         I8PtrTy(TypedPointerType::get(I8Ty, 0)), Stream(Stream),
136         StrtabBuilder(StrtabBuilder), M(M), VE(M, I8PtrTy), Buffer(Buffer),
137         BitcodeStartBit(Stream.GetCurrentBitNo()),
138         PointerMap(PointerTypeAnalysis::run(M)) {
139     GlobalValueId = VE.getValues().size();
140     // Enumerate the typed pointers
141     for (auto El : PointerMap)
142       VE.EnumerateType(El.second);
143   }
144 
145   /// Emit the current module to the bitstream.
146   void write();
147 
148   static uint64_t getAttrKindEncoding(Attribute::AttrKind Kind);
149   static void writeStringRecord(BitstreamWriter &Stream, unsigned Code,
150                                 StringRef Str, unsigned AbbrevToUse);
151   static void writeIdentificationBlock(BitstreamWriter &Stream);
152   static void emitSignedInt64(SmallVectorImpl<uint64_t> &Vals, uint64_t V);
153   static void emitWideAPInt(SmallVectorImpl<uint64_t> &Vals, const APInt &A);
154 
155   static unsigned getEncodedComdatSelectionKind(const Comdat &C);
156   static unsigned getEncodedLinkage(const GlobalValue::LinkageTypes Linkage);
157   static unsigned getEncodedLinkage(const GlobalValue &GV);
158   static unsigned getEncodedVisibility(const GlobalValue &GV);
159   static unsigned getEncodedThreadLocalMode(const GlobalValue &GV);
160   static unsigned getEncodedDLLStorageClass(const GlobalValue &GV);
161   static unsigned getEncodedCastOpcode(unsigned Opcode);
162   static unsigned getEncodedUnaryOpcode(unsigned Opcode);
163   static unsigned getEncodedBinaryOpcode(unsigned Opcode);
164   static unsigned getEncodedRMWOperation(AtomicRMWInst::BinOp Op);
165   static unsigned getEncodedOrdering(AtomicOrdering Ordering);
166   static uint64_t getOptimizationFlags(const Value *V);
167 
168 private:
169   void writeModuleVersion();
170   void writePerModuleGlobalValueSummary();
171 
172   void writePerModuleFunctionSummaryRecord(SmallVector<uint64_t, 64> &NameVals,
173                                            GlobalValueSummary *Summary,
174                                            unsigned ValueID,
175                                            unsigned FSCallsAbbrev,
176                                            unsigned FSCallsProfileAbbrev,
177                                            const Function &F);
178   void writeModuleLevelReferences(const GlobalVariable &V,
179                                   SmallVector<uint64_t, 64> &NameVals,
180                                   unsigned FSModRefsAbbrev,
181                                   unsigned FSModVTableRefsAbbrev);
182 
183   void assignValueId(GlobalValue::GUID ValGUID) {
184     GUIDToValueIdMap[ValGUID] = ++GlobalValueId;
185   }
186 
187   unsigned getValueId(GlobalValue::GUID ValGUID) {
188     const auto &VMI = GUIDToValueIdMap.find(ValGUID);
189     // Expect that any GUID value had a value Id assigned by an
190     // earlier call to assignValueId.
191     assert(VMI != GUIDToValueIdMap.end() &&
192            "GUID does not have assigned value Id");
193     return VMI->second;
194   }
195 
196   // Helper to get the valueId for the type of value recorded in VI.
197   unsigned getValueId(ValueInfo VI) {
198     if (!VI.haveGVs() || !VI.getValue())
199       return getValueId(VI.getGUID());
200     return VE.getValueID(VI.getValue());
201   }
202 
203   std::map<GlobalValue::GUID, unsigned> &valueIds() { return GUIDToValueIdMap; }
204 
205   uint64_t bitcodeStartBit() { return BitcodeStartBit; }
206 
207   size_t addToStrtab(StringRef Str);
208 
209   unsigned createDILocationAbbrev();
210   unsigned createGenericDINodeAbbrev();
211 
212   void writeAttributeGroupTable();
213   void writeAttributeTable();
214   void writeTypeTable();
215   void writeComdats();
216   void writeValueSymbolTableForwardDecl();
217   void writeModuleInfo();
218   void writeValueAsMetadata(const ValueAsMetadata *MD,
219                             SmallVectorImpl<uint64_t> &Record);
220   void writeMDTuple(const MDTuple *N, SmallVectorImpl<uint64_t> &Record,
221                     unsigned Abbrev);
222   void writeDILocation(const DILocation *N, SmallVectorImpl<uint64_t> &Record,
223                        unsigned &Abbrev);
224   void writeGenericDINode(const GenericDINode *N,
225                           SmallVectorImpl<uint64_t> &Record, unsigned &Abbrev) {
226     llvm_unreachable("DXIL cannot contain GenericDI Nodes");
227   }
228   void writeDISubrange(const DISubrange *N, SmallVectorImpl<uint64_t> &Record,
229                        unsigned Abbrev);
230   void writeDIGenericSubrange(const DIGenericSubrange *N,
231                               SmallVectorImpl<uint64_t> &Record,
232                               unsigned Abbrev) {
233     llvm_unreachable("DXIL cannot contain DIGenericSubrange Nodes");
234   }
235   void writeDIEnumerator(const DIEnumerator *N,
236                          SmallVectorImpl<uint64_t> &Record, unsigned Abbrev);
237   void writeDIBasicType(const DIBasicType *N, SmallVectorImpl<uint64_t> &Record,
238                         unsigned Abbrev);
239   void writeDIStringType(const DIStringType *N,
240                          SmallVectorImpl<uint64_t> &Record, unsigned Abbrev) {
241     llvm_unreachable("DXIL cannot contain DIStringType Nodes");
242   }
243   void writeDIDerivedType(const DIDerivedType *N,
244                           SmallVectorImpl<uint64_t> &Record, unsigned Abbrev);
245   void writeDICompositeType(const DICompositeType *N,
246                             SmallVectorImpl<uint64_t> &Record, unsigned Abbrev);
247   void writeDISubroutineType(const DISubroutineType *N,
248                              SmallVectorImpl<uint64_t> &Record,
249                              unsigned Abbrev);
250   void writeDIFile(const DIFile *N, SmallVectorImpl<uint64_t> &Record,
251                    unsigned Abbrev);
252   void writeDICompileUnit(const DICompileUnit *N,
253                           SmallVectorImpl<uint64_t> &Record, unsigned Abbrev);
254   void writeDISubprogram(const DISubprogram *N,
255                          SmallVectorImpl<uint64_t> &Record, unsigned Abbrev);
256   void writeDILexicalBlock(const DILexicalBlock *N,
257                            SmallVectorImpl<uint64_t> &Record, unsigned Abbrev);
258   void writeDILexicalBlockFile(const DILexicalBlockFile *N,
259                                SmallVectorImpl<uint64_t> &Record,
260                                unsigned Abbrev);
261   void writeDICommonBlock(const DICommonBlock *N,
262                           SmallVectorImpl<uint64_t> &Record, unsigned Abbrev) {
263     llvm_unreachable("DXIL cannot contain DICommonBlock Nodes");
264   }
265   void writeDINamespace(const DINamespace *N, SmallVectorImpl<uint64_t> &Record,
266                         unsigned Abbrev);
267   void writeDIMacro(const DIMacro *N, SmallVectorImpl<uint64_t> &Record,
268                     unsigned Abbrev) {
269     llvm_unreachable("DXIL cannot contain DIMacro Nodes");
270   }
271   void writeDIMacroFile(const DIMacroFile *N, SmallVectorImpl<uint64_t> &Record,
272                         unsigned Abbrev) {
273     llvm_unreachable("DXIL cannot contain DIMacroFile Nodes");
274   }
275   void writeDIArgList(const DIArgList *N, SmallVectorImpl<uint64_t> &Record,
276                       unsigned Abbrev) {
277     llvm_unreachable("DXIL cannot contain DIArgList Nodes");
278   }
279   void writeDIModule(const DIModule *N, SmallVectorImpl<uint64_t> &Record,
280                      unsigned Abbrev);
281   void writeDITemplateTypeParameter(const DITemplateTypeParameter *N,
282                                     SmallVectorImpl<uint64_t> &Record,
283                                     unsigned Abbrev);
284   void writeDITemplateValueParameter(const DITemplateValueParameter *N,
285                                      SmallVectorImpl<uint64_t> &Record,
286                                      unsigned Abbrev);
287   void writeDIGlobalVariable(const DIGlobalVariable *N,
288                              SmallVectorImpl<uint64_t> &Record,
289                              unsigned Abbrev);
290   void writeDILocalVariable(const DILocalVariable *N,
291                             SmallVectorImpl<uint64_t> &Record, unsigned Abbrev);
292   void writeDILabel(const DILabel *N, SmallVectorImpl<uint64_t> &Record,
293                     unsigned Abbrev) {
294     llvm_unreachable("DXIL cannot contain DILabel Nodes");
295   }
296   void writeDIExpression(const DIExpression *N,
297                          SmallVectorImpl<uint64_t> &Record, unsigned Abbrev);
298   void writeDIGlobalVariableExpression(const DIGlobalVariableExpression *N,
299                                        SmallVectorImpl<uint64_t> &Record,
300                                        unsigned Abbrev) {
301     llvm_unreachable("DXIL cannot contain GlobalVariableExpression Nodes");
302   }
303   void writeDIObjCProperty(const DIObjCProperty *N,
304                            SmallVectorImpl<uint64_t> &Record, unsigned Abbrev);
305   void writeDIImportedEntity(const DIImportedEntity *N,
306                              SmallVectorImpl<uint64_t> &Record,
307                              unsigned Abbrev);
308   unsigned createNamedMetadataAbbrev();
309   void writeNamedMetadata(SmallVectorImpl<uint64_t> &Record);
310   unsigned createMetadataStringsAbbrev();
311   void writeMetadataStrings(ArrayRef<const Metadata *> Strings,
312                             SmallVectorImpl<uint64_t> &Record);
313   void writeMetadataRecords(ArrayRef<const Metadata *> MDs,
314                             SmallVectorImpl<uint64_t> &Record,
315                             std::vector<unsigned> *MDAbbrevs = nullptr,
316                             std::vector<uint64_t> *IndexPos = nullptr);
317   void writeModuleMetadata();
318   void writeFunctionMetadata(const Function &F);
319   void writeFunctionMetadataAttachment(const Function &F);
320   void pushGlobalMetadataAttachment(SmallVectorImpl<uint64_t> &Record,
321                                     const GlobalObject &GO);
322   void writeModuleMetadataKinds();
323   void writeOperandBundleTags();
324   void writeSyncScopeNames();
325   void writeConstants(unsigned FirstVal, unsigned LastVal, bool isGlobal);
326   void writeModuleConstants();
327   bool pushValueAndType(const Value *V, unsigned InstID,
328                         SmallVectorImpl<unsigned> &Vals);
329   void writeOperandBundles(const CallBase &CB, unsigned InstID);
330   void pushValue(const Value *V, unsigned InstID,
331                  SmallVectorImpl<unsigned> &Vals);
332   void pushValueSigned(const Value *V, unsigned InstID,
333                        SmallVectorImpl<uint64_t> &Vals);
334   void writeInstruction(const Instruction &I, unsigned InstID,
335                         SmallVectorImpl<unsigned> &Vals);
336   void writeFunctionLevelValueSymbolTable(const ValueSymbolTable &VST);
337   void writeGlobalValueSymbolTable(
338       DenseMap<const Function *, uint64_t> &FunctionToBitcodeIndex);
339   void writeUseList(UseListOrder &&Order);
340   void writeUseListBlock(const Function *F);
341   void writeFunction(const Function &F);
342   void writeBlockInfo();
343 
344   unsigned getEncodedSyncScopeID(SyncScope::ID SSID) { return unsigned(SSID); }
345 
346   unsigned getEncodedAlign(MaybeAlign Alignment) { return encode(Alignment); }
347 
348   unsigned getTypeID(Type *T, const Value *V = nullptr);
349   /// getGlobalObjectValueTypeID - returns the element type for a GlobalObject
350   ///
351   /// GlobalObject types are saved by PointerTypeAnalysis as pointers to the
352   /// GlobalObject, but in the bitcode writer we need the pointer element type.
353   unsigned getGlobalObjectValueTypeID(Type *T, const GlobalObject *G);
354 };
355 
356 } // namespace dxil
357 } // namespace llvm
358 
359 using namespace llvm;
360 using namespace llvm::dxil;
361 
362 ////////////////////////////////////////////////////////////////////////////////
363 /// Begin dxil::BitcodeWriter Implementation
364 ////////////////////////////////////////////////////////////////////////////////
365 
366 dxil::BitcodeWriter::BitcodeWriter(SmallVectorImpl<char> &Buffer,
367                                    raw_fd_stream *FS)
368     : Buffer(Buffer), Stream(new BitstreamWriter(Buffer, FS, 512)) {
369   // Emit the file header.
370   Stream->Emit((unsigned)'B', 8);
371   Stream->Emit((unsigned)'C', 8);
372   Stream->Emit(0x0, 4);
373   Stream->Emit(0xC, 4);
374   Stream->Emit(0xE, 4);
375   Stream->Emit(0xD, 4);
376 }
377 
378 dxil::BitcodeWriter::~BitcodeWriter() { assert(WroteStrtab); }
379 
380 /// Write the specified module to the specified output stream.
381 void dxil::WriteDXILToFile(const Module &M, raw_ostream &Out) {
382   SmallVector<char, 0> Buffer;
383   Buffer.reserve(256 * 1024);
384 
385   // If this is darwin or another generic macho target, reserve space for the
386   // header.
387   Triple TT(M.getTargetTriple());
388   if (TT.isOSDarwin() || TT.isOSBinFormatMachO())
389     Buffer.insert(Buffer.begin(), BWH_HeaderSize, 0);
390 
391   BitcodeWriter Writer(Buffer, dyn_cast<raw_fd_stream>(&Out));
392   Writer.writeModule(M);
393   Writer.writeSymtab();
394   Writer.writeStrtab();
395 
396   // Write the generated bitstream to "Out".
397   if (!Buffer.empty())
398     Out.write((char *)&Buffer.front(), Buffer.size());
399 }
400 
401 void BitcodeWriter::writeBlob(unsigned Block, unsigned Record, StringRef Blob) {
402   Stream->EnterSubblock(Block, 3);
403 
404   auto Abbv = std::make_shared<BitCodeAbbrev>();
405   Abbv->Add(BitCodeAbbrevOp(Record));
406   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));
407   auto AbbrevNo = Stream->EmitAbbrev(std::move(Abbv));
408 
409   Stream->EmitRecordWithBlob(AbbrevNo, ArrayRef<uint64_t>{Record}, Blob);
410 
411   Stream->ExitBlock();
412 }
413 
414 void BitcodeWriter::writeSymtab() {
415   assert(!WroteStrtab && !WroteSymtab);
416 
417   // If any module has module-level inline asm, we will require a registered asm
418   // parser for the target so that we can create an accurate symbol table for
419   // the module.
420   for (Module *M : Mods) {
421     if (M->getModuleInlineAsm().empty())
422       continue;
423   }
424 
425   WroteSymtab = true;
426   SmallVector<char, 0> Symtab;
427   // The irsymtab::build function may be unable to create a symbol table if the
428   // module is malformed (e.g. it contains an invalid alias). Writing a symbol
429   // table is not required for correctness, but we still want to be able to
430   // write malformed modules to bitcode files, so swallow the error.
431   if (Error E = irsymtab::build(Mods, Symtab, StrtabBuilder, Alloc)) {
432     consumeError(std::move(E));
433     return;
434   }
435 
436   writeBlob(bitc::SYMTAB_BLOCK_ID, bitc::SYMTAB_BLOB,
437             {Symtab.data(), Symtab.size()});
438 }
439 
440 void BitcodeWriter::writeStrtab() {
441   assert(!WroteStrtab);
442 
443   std::vector<char> Strtab;
444   StrtabBuilder.finalizeInOrder();
445   Strtab.resize(StrtabBuilder.getSize());
446   StrtabBuilder.write((uint8_t *)Strtab.data());
447 
448   writeBlob(bitc::STRTAB_BLOCK_ID, bitc::STRTAB_BLOB,
449             {Strtab.data(), Strtab.size()});
450 
451   WroteStrtab = true;
452 }
453 
454 void BitcodeWriter::copyStrtab(StringRef Strtab) {
455   writeBlob(bitc::STRTAB_BLOCK_ID, bitc::STRTAB_BLOB, Strtab);
456   WroteStrtab = true;
457 }
458 
459 void BitcodeWriter::writeModule(const Module &M) {
460   assert(!WroteStrtab);
461 
462   // The Mods vector is used by irsymtab::build, which requires non-const
463   // Modules in case it needs to materialize metadata. But the bitcode writer
464   // requires that the module is materialized, so we can cast to non-const here,
465   // after checking that it is in fact materialized.
466   assert(M.isMaterialized());
467   Mods.push_back(const_cast<Module *>(&M));
468 
469   DXILBitcodeWriter ModuleWriter(M, Buffer, StrtabBuilder, *Stream);
470   ModuleWriter.write();
471 }
472 
473 ////////////////////////////////////////////////////////////////////////////////
474 /// Begin dxil::BitcodeWriterBase Implementation
475 ////////////////////////////////////////////////////////////////////////////////
476 
477 unsigned DXILBitcodeWriter::getEncodedCastOpcode(unsigned Opcode) {
478   switch (Opcode) {
479   default:
480     llvm_unreachable("Unknown cast instruction!");
481   case Instruction::Trunc:
482     return bitc::CAST_TRUNC;
483   case Instruction::ZExt:
484     return bitc::CAST_ZEXT;
485   case Instruction::SExt:
486     return bitc::CAST_SEXT;
487   case Instruction::FPToUI:
488     return bitc::CAST_FPTOUI;
489   case Instruction::FPToSI:
490     return bitc::CAST_FPTOSI;
491   case Instruction::UIToFP:
492     return bitc::CAST_UITOFP;
493   case Instruction::SIToFP:
494     return bitc::CAST_SITOFP;
495   case Instruction::FPTrunc:
496     return bitc::CAST_FPTRUNC;
497   case Instruction::FPExt:
498     return bitc::CAST_FPEXT;
499   case Instruction::PtrToInt:
500     return bitc::CAST_PTRTOINT;
501   case Instruction::IntToPtr:
502     return bitc::CAST_INTTOPTR;
503   case Instruction::BitCast:
504     return bitc::CAST_BITCAST;
505   case Instruction::AddrSpaceCast:
506     return bitc::CAST_ADDRSPACECAST;
507   }
508 }
509 
510 unsigned DXILBitcodeWriter::getEncodedUnaryOpcode(unsigned Opcode) {
511   switch (Opcode) {
512   default:
513     llvm_unreachable("Unknown binary instruction!");
514   case Instruction::FNeg:
515     return bitc::UNOP_FNEG;
516   }
517 }
518 
519 unsigned DXILBitcodeWriter::getEncodedBinaryOpcode(unsigned Opcode) {
520   switch (Opcode) {
521   default:
522     llvm_unreachable("Unknown binary instruction!");
523   case Instruction::Add:
524   case Instruction::FAdd:
525     return bitc::BINOP_ADD;
526   case Instruction::Sub:
527   case Instruction::FSub:
528     return bitc::BINOP_SUB;
529   case Instruction::Mul:
530   case Instruction::FMul:
531     return bitc::BINOP_MUL;
532   case Instruction::UDiv:
533     return bitc::BINOP_UDIV;
534   case Instruction::FDiv:
535   case Instruction::SDiv:
536     return bitc::BINOP_SDIV;
537   case Instruction::URem:
538     return bitc::BINOP_UREM;
539   case Instruction::FRem:
540   case Instruction::SRem:
541     return bitc::BINOP_SREM;
542   case Instruction::Shl:
543     return bitc::BINOP_SHL;
544   case Instruction::LShr:
545     return bitc::BINOP_LSHR;
546   case Instruction::AShr:
547     return bitc::BINOP_ASHR;
548   case Instruction::And:
549     return bitc::BINOP_AND;
550   case Instruction::Or:
551     return bitc::BINOP_OR;
552   case Instruction::Xor:
553     return bitc::BINOP_XOR;
554   }
555 }
556 
557 unsigned DXILBitcodeWriter::getTypeID(Type *T, const Value *V) {
558   if (!T->isOpaquePointerTy() &&
559       // For Constant, always check PointerMap to make sure OpaquePointer in
560       // things like constant struct/array works.
561       (!V || !isa<Constant>(V)))
562     return VE.getTypeID(T);
563   auto It = PointerMap.find(V);
564   if (It != PointerMap.end())
565     return VE.getTypeID(It->second);
566   // For Constant, return T when cannot find in PointerMap.
567   // FIXME: support ConstantPointerNull which could map to more than one
568   // TypedPointerType.
569   // See https://github.com/llvm/llvm-project/issues/57942.
570   if (V && isa<Constant>(V) && !isa<ConstantPointerNull>(V))
571     return VE.getTypeID(T);
572   return VE.getTypeID(I8PtrTy);
573 }
574 
575 unsigned DXILBitcodeWriter::getGlobalObjectValueTypeID(Type *T,
576                                                        const GlobalObject *G) {
577   auto It = PointerMap.find(G);
578   if (It != PointerMap.end()) {
579     TypedPointerType *PtrTy = cast<TypedPointerType>(It->second);
580     return VE.getTypeID(PtrTy->getElementType());
581   }
582   return VE.getTypeID(T);
583 }
584 
585 unsigned DXILBitcodeWriter::getEncodedRMWOperation(AtomicRMWInst::BinOp Op) {
586   switch (Op) {
587   default:
588     llvm_unreachable("Unknown RMW operation!");
589   case AtomicRMWInst::Xchg:
590     return bitc::RMW_XCHG;
591   case AtomicRMWInst::Add:
592     return bitc::RMW_ADD;
593   case AtomicRMWInst::Sub:
594     return bitc::RMW_SUB;
595   case AtomicRMWInst::And:
596     return bitc::RMW_AND;
597   case AtomicRMWInst::Nand:
598     return bitc::RMW_NAND;
599   case AtomicRMWInst::Or:
600     return bitc::RMW_OR;
601   case AtomicRMWInst::Xor:
602     return bitc::RMW_XOR;
603   case AtomicRMWInst::Max:
604     return bitc::RMW_MAX;
605   case AtomicRMWInst::Min:
606     return bitc::RMW_MIN;
607   case AtomicRMWInst::UMax:
608     return bitc::RMW_UMAX;
609   case AtomicRMWInst::UMin:
610     return bitc::RMW_UMIN;
611   case AtomicRMWInst::FAdd:
612     return bitc::RMW_FADD;
613   case AtomicRMWInst::FSub:
614     return bitc::RMW_FSUB;
615   case AtomicRMWInst::FMax:
616     return bitc::RMW_FMAX;
617   case AtomicRMWInst::FMin:
618     return bitc::RMW_FMIN;
619   }
620 }
621 
622 unsigned DXILBitcodeWriter::getEncodedOrdering(AtomicOrdering Ordering) {
623   switch (Ordering) {
624   case AtomicOrdering::NotAtomic:
625     return bitc::ORDERING_NOTATOMIC;
626   case AtomicOrdering::Unordered:
627     return bitc::ORDERING_UNORDERED;
628   case AtomicOrdering::Monotonic:
629     return bitc::ORDERING_MONOTONIC;
630   case AtomicOrdering::Acquire:
631     return bitc::ORDERING_ACQUIRE;
632   case AtomicOrdering::Release:
633     return bitc::ORDERING_RELEASE;
634   case AtomicOrdering::AcquireRelease:
635     return bitc::ORDERING_ACQREL;
636   case AtomicOrdering::SequentiallyConsistent:
637     return bitc::ORDERING_SEQCST;
638   }
639   llvm_unreachable("Invalid ordering");
640 }
641 
642 void DXILBitcodeWriter::writeStringRecord(BitstreamWriter &Stream,
643                                           unsigned Code, StringRef Str,
644                                           unsigned AbbrevToUse) {
645   SmallVector<unsigned, 64> Vals;
646 
647   // Code: [strchar x N]
648   for (char C : Str) {
649     if (AbbrevToUse && !BitCodeAbbrevOp::isChar6(C))
650       AbbrevToUse = 0;
651     Vals.push_back(C);
652   }
653 
654   // Emit the finished record.
655   Stream.EmitRecord(Code, Vals, AbbrevToUse);
656 }
657 
658 uint64_t DXILBitcodeWriter::getAttrKindEncoding(Attribute::AttrKind Kind) {
659   switch (Kind) {
660   case Attribute::Alignment:
661     return bitc::ATTR_KIND_ALIGNMENT;
662   case Attribute::AlwaysInline:
663     return bitc::ATTR_KIND_ALWAYS_INLINE;
664   case Attribute::ArgMemOnly:
665     return bitc::ATTR_KIND_ARGMEMONLY;
666   case Attribute::Builtin:
667     return bitc::ATTR_KIND_BUILTIN;
668   case Attribute::ByVal:
669     return bitc::ATTR_KIND_BY_VAL;
670   case Attribute::Convergent:
671     return bitc::ATTR_KIND_CONVERGENT;
672   case Attribute::InAlloca:
673     return bitc::ATTR_KIND_IN_ALLOCA;
674   case Attribute::Cold:
675     return bitc::ATTR_KIND_COLD;
676   case Attribute::InlineHint:
677     return bitc::ATTR_KIND_INLINE_HINT;
678   case Attribute::InReg:
679     return bitc::ATTR_KIND_IN_REG;
680   case Attribute::JumpTable:
681     return bitc::ATTR_KIND_JUMP_TABLE;
682   case Attribute::MinSize:
683     return bitc::ATTR_KIND_MIN_SIZE;
684   case Attribute::Naked:
685     return bitc::ATTR_KIND_NAKED;
686   case Attribute::Nest:
687     return bitc::ATTR_KIND_NEST;
688   case Attribute::NoAlias:
689     return bitc::ATTR_KIND_NO_ALIAS;
690   case Attribute::NoBuiltin:
691     return bitc::ATTR_KIND_NO_BUILTIN;
692   case Attribute::NoCapture:
693     return bitc::ATTR_KIND_NO_CAPTURE;
694   case Attribute::NoDuplicate:
695     return bitc::ATTR_KIND_NO_DUPLICATE;
696   case Attribute::NoImplicitFloat:
697     return bitc::ATTR_KIND_NO_IMPLICIT_FLOAT;
698   case Attribute::NoInline:
699     return bitc::ATTR_KIND_NO_INLINE;
700   case Attribute::NonLazyBind:
701     return bitc::ATTR_KIND_NON_LAZY_BIND;
702   case Attribute::NonNull:
703     return bitc::ATTR_KIND_NON_NULL;
704   case Attribute::Dereferenceable:
705     return bitc::ATTR_KIND_DEREFERENCEABLE;
706   case Attribute::DereferenceableOrNull:
707     return bitc::ATTR_KIND_DEREFERENCEABLE_OR_NULL;
708   case Attribute::NoRedZone:
709     return bitc::ATTR_KIND_NO_RED_ZONE;
710   case Attribute::NoReturn:
711     return bitc::ATTR_KIND_NO_RETURN;
712   case Attribute::NoUnwind:
713     return bitc::ATTR_KIND_NO_UNWIND;
714   case Attribute::OptimizeForSize:
715     return bitc::ATTR_KIND_OPTIMIZE_FOR_SIZE;
716   case Attribute::OptimizeNone:
717     return bitc::ATTR_KIND_OPTIMIZE_NONE;
718   case Attribute::ReadNone:
719     return bitc::ATTR_KIND_READ_NONE;
720   case Attribute::ReadOnly:
721     return bitc::ATTR_KIND_READ_ONLY;
722   case Attribute::Returned:
723     return bitc::ATTR_KIND_RETURNED;
724   case Attribute::ReturnsTwice:
725     return bitc::ATTR_KIND_RETURNS_TWICE;
726   case Attribute::SExt:
727     return bitc::ATTR_KIND_S_EXT;
728   case Attribute::StackAlignment:
729     return bitc::ATTR_KIND_STACK_ALIGNMENT;
730   case Attribute::StackProtect:
731     return bitc::ATTR_KIND_STACK_PROTECT;
732   case Attribute::StackProtectReq:
733     return bitc::ATTR_KIND_STACK_PROTECT_REQ;
734   case Attribute::StackProtectStrong:
735     return bitc::ATTR_KIND_STACK_PROTECT_STRONG;
736   case Attribute::SafeStack:
737     return bitc::ATTR_KIND_SAFESTACK;
738   case Attribute::StructRet:
739     return bitc::ATTR_KIND_STRUCT_RET;
740   case Attribute::SanitizeAddress:
741     return bitc::ATTR_KIND_SANITIZE_ADDRESS;
742   case Attribute::SanitizeThread:
743     return bitc::ATTR_KIND_SANITIZE_THREAD;
744   case Attribute::SanitizeMemory:
745     return bitc::ATTR_KIND_SANITIZE_MEMORY;
746   case Attribute::UWTable:
747     return bitc::ATTR_KIND_UW_TABLE;
748   case Attribute::ZExt:
749     return bitc::ATTR_KIND_Z_EXT;
750   case Attribute::EndAttrKinds:
751     llvm_unreachable("Can not encode end-attribute kinds marker.");
752   case Attribute::None:
753     llvm_unreachable("Can not encode none-attribute.");
754   case Attribute::EmptyKey:
755   case Attribute::TombstoneKey:
756     llvm_unreachable("Trying to encode EmptyKey/TombstoneKey");
757   default:
758     llvm_unreachable("Trying to encode attribute not supported by DXIL. These "
759                      "should be stripped in DXILPrepare");
760   }
761 
762   llvm_unreachable("Trying to encode unknown attribute");
763 }
764 
765 void DXILBitcodeWriter::emitSignedInt64(SmallVectorImpl<uint64_t> &Vals,
766                                         uint64_t V) {
767   if ((int64_t)V >= 0)
768     Vals.push_back(V << 1);
769   else
770     Vals.push_back((-V << 1) | 1);
771 }
772 
773 void DXILBitcodeWriter::emitWideAPInt(SmallVectorImpl<uint64_t> &Vals,
774                                       const APInt &A) {
775   // We have an arbitrary precision integer value to write whose
776   // bit width is > 64. However, in canonical unsigned integer
777   // format it is likely that the high bits are going to be zero.
778   // So, we only write the number of active words.
779   unsigned NumWords = A.getActiveWords();
780   const uint64_t *RawData = A.getRawData();
781   for (unsigned i = 0; i < NumWords; i++)
782     emitSignedInt64(Vals, RawData[i]);
783 }
784 
785 uint64_t DXILBitcodeWriter::getOptimizationFlags(const Value *V) {
786   uint64_t Flags = 0;
787 
788   if (const auto *OBO = dyn_cast<OverflowingBinaryOperator>(V)) {
789     if (OBO->hasNoSignedWrap())
790       Flags |= 1 << bitc::OBO_NO_SIGNED_WRAP;
791     if (OBO->hasNoUnsignedWrap())
792       Flags |= 1 << bitc::OBO_NO_UNSIGNED_WRAP;
793   } else if (const auto *PEO = dyn_cast<PossiblyExactOperator>(V)) {
794     if (PEO->isExact())
795       Flags |= 1 << bitc::PEO_EXACT;
796   } else if (const auto *FPMO = dyn_cast<FPMathOperator>(V)) {
797     if (FPMO->hasAllowReassoc())
798       Flags |= bitc::AllowReassoc;
799     if (FPMO->hasNoNaNs())
800       Flags |= bitc::NoNaNs;
801     if (FPMO->hasNoInfs())
802       Flags |= bitc::NoInfs;
803     if (FPMO->hasNoSignedZeros())
804       Flags |= bitc::NoSignedZeros;
805     if (FPMO->hasAllowReciprocal())
806       Flags |= bitc::AllowReciprocal;
807     if (FPMO->hasAllowContract())
808       Flags |= bitc::AllowContract;
809     if (FPMO->hasApproxFunc())
810       Flags |= bitc::ApproxFunc;
811   }
812 
813   return Flags;
814 }
815 
816 unsigned
817 DXILBitcodeWriter::getEncodedLinkage(const GlobalValue::LinkageTypes Linkage) {
818   switch (Linkage) {
819   case GlobalValue::ExternalLinkage:
820     return 0;
821   case GlobalValue::WeakAnyLinkage:
822     return 16;
823   case GlobalValue::AppendingLinkage:
824     return 2;
825   case GlobalValue::InternalLinkage:
826     return 3;
827   case GlobalValue::LinkOnceAnyLinkage:
828     return 18;
829   case GlobalValue::ExternalWeakLinkage:
830     return 7;
831   case GlobalValue::CommonLinkage:
832     return 8;
833   case GlobalValue::PrivateLinkage:
834     return 9;
835   case GlobalValue::WeakODRLinkage:
836     return 17;
837   case GlobalValue::LinkOnceODRLinkage:
838     return 19;
839   case GlobalValue::AvailableExternallyLinkage:
840     return 12;
841   }
842   llvm_unreachable("Invalid linkage");
843 }
844 
845 unsigned DXILBitcodeWriter::getEncodedLinkage(const GlobalValue &GV) {
846   return getEncodedLinkage(GV.getLinkage());
847 }
848 
849 unsigned DXILBitcodeWriter::getEncodedVisibility(const GlobalValue &GV) {
850   switch (GV.getVisibility()) {
851   case GlobalValue::DefaultVisibility:
852     return 0;
853   case GlobalValue::HiddenVisibility:
854     return 1;
855   case GlobalValue::ProtectedVisibility:
856     return 2;
857   }
858   llvm_unreachable("Invalid visibility");
859 }
860 
861 unsigned DXILBitcodeWriter::getEncodedDLLStorageClass(const GlobalValue &GV) {
862   switch (GV.getDLLStorageClass()) {
863   case GlobalValue::DefaultStorageClass:
864     return 0;
865   case GlobalValue::DLLImportStorageClass:
866     return 1;
867   case GlobalValue::DLLExportStorageClass:
868     return 2;
869   }
870   llvm_unreachable("Invalid DLL storage class");
871 }
872 
873 unsigned DXILBitcodeWriter::getEncodedThreadLocalMode(const GlobalValue &GV) {
874   switch (GV.getThreadLocalMode()) {
875   case GlobalVariable::NotThreadLocal:
876     return 0;
877   case GlobalVariable::GeneralDynamicTLSModel:
878     return 1;
879   case GlobalVariable::LocalDynamicTLSModel:
880     return 2;
881   case GlobalVariable::InitialExecTLSModel:
882     return 3;
883   case GlobalVariable::LocalExecTLSModel:
884     return 4;
885   }
886   llvm_unreachable("Invalid TLS model");
887 }
888 
889 unsigned DXILBitcodeWriter::getEncodedComdatSelectionKind(const Comdat &C) {
890   switch (C.getSelectionKind()) {
891   case Comdat::Any:
892     return bitc::COMDAT_SELECTION_KIND_ANY;
893   case Comdat::ExactMatch:
894     return bitc::COMDAT_SELECTION_KIND_EXACT_MATCH;
895   case Comdat::Largest:
896     return bitc::COMDAT_SELECTION_KIND_LARGEST;
897   case Comdat::NoDeduplicate:
898     return bitc::COMDAT_SELECTION_KIND_NO_DUPLICATES;
899   case Comdat::SameSize:
900     return bitc::COMDAT_SELECTION_KIND_SAME_SIZE;
901   }
902   llvm_unreachable("Invalid selection kind");
903 }
904 
905 ////////////////////////////////////////////////////////////////////////////////
906 /// Begin DXILBitcodeWriter Implementation
907 ////////////////////////////////////////////////////////////////////////////////
908 
909 void DXILBitcodeWriter::writeAttributeGroupTable() {
910   const std::vector<ValueEnumerator::IndexAndAttrSet> &AttrGrps =
911       VE.getAttributeGroups();
912   if (AttrGrps.empty())
913     return;
914 
915   Stream.EnterSubblock(bitc::PARAMATTR_GROUP_BLOCK_ID, 3);
916 
917   SmallVector<uint64_t, 64> Record;
918   for (ValueEnumerator::IndexAndAttrSet Pair : AttrGrps) {
919     unsigned AttrListIndex = Pair.first;
920     AttributeSet AS = Pair.second;
921     Record.push_back(VE.getAttributeGroupID(Pair));
922     Record.push_back(AttrListIndex);
923 
924     for (Attribute Attr : AS) {
925       if (Attr.isEnumAttribute()) {
926         uint64_t Val = getAttrKindEncoding(Attr.getKindAsEnum());
927         assert(Val <= bitc::ATTR_KIND_ARGMEMONLY &&
928                "DXIL does not support attributes above ATTR_KIND_ARGMEMONLY");
929         Record.push_back(0);
930         Record.push_back(Val);
931       } else if (Attr.isIntAttribute()) {
932         uint64_t Val = getAttrKindEncoding(Attr.getKindAsEnum());
933         assert(Val <= bitc::ATTR_KIND_ARGMEMONLY &&
934                "DXIL does not support attributes above ATTR_KIND_ARGMEMONLY");
935         Record.push_back(1);
936         Record.push_back(Val);
937         Record.push_back(Attr.getValueAsInt());
938       } else {
939         StringRef Kind = Attr.getKindAsString();
940         StringRef Val = Attr.getValueAsString();
941 
942         Record.push_back(Val.empty() ? 3 : 4);
943         Record.append(Kind.begin(), Kind.end());
944         Record.push_back(0);
945         if (!Val.empty()) {
946           Record.append(Val.begin(), Val.end());
947           Record.push_back(0);
948         }
949       }
950     }
951 
952     Stream.EmitRecord(bitc::PARAMATTR_GRP_CODE_ENTRY, Record);
953     Record.clear();
954   }
955 
956   Stream.ExitBlock();
957 }
958 
959 void DXILBitcodeWriter::writeAttributeTable() {
960   const std::vector<AttributeList> &Attrs = VE.getAttributeLists();
961   if (Attrs.empty())
962     return;
963 
964   Stream.EnterSubblock(bitc::PARAMATTR_BLOCK_ID, 3);
965 
966   SmallVector<uint64_t, 64> Record;
967   for (unsigned i = 0, e = Attrs.size(); i != e; ++i) {
968     AttributeList AL = Attrs[i];
969     for (unsigned i : AL.indexes()) {
970       AttributeSet AS = AL.getAttributes(i);
971       if (AS.hasAttributes())
972         Record.push_back(VE.getAttributeGroupID({i, AS}));
973     }
974 
975     Stream.EmitRecord(bitc::PARAMATTR_CODE_ENTRY, Record);
976     Record.clear();
977   }
978 
979   Stream.ExitBlock();
980 }
981 
982 /// WriteTypeTable - Write out the type table for a module.
983 void DXILBitcodeWriter::writeTypeTable() {
984   const ValueEnumerator::TypeList &TypeList = VE.getTypes();
985 
986   Stream.EnterSubblock(bitc::TYPE_BLOCK_ID_NEW, 4 /*count from # abbrevs */);
987   SmallVector<uint64_t, 64> TypeVals;
988 
989   uint64_t NumBits = VE.computeBitsRequiredForTypeIndicies();
990 
991   // Abbrev for TYPE_CODE_POINTER.
992   auto Abbv = std::make_shared<BitCodeAbbrev>();
993   Abbv->Add(BitCodeAbbrevOp(bitc::TYPE_CODE_POINTER));
994   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, NumBits));
995   Abbv->Add(BitCodeAbbrevOp(0)); // Addrspace = 0
996   unsigned PtrAbbrev = Stream.EmitAbbrev(std::move(Abbv));
997 
998   // Abbrev for TYPE_CODE_FUNCTION.
999   Abbv = std::make_shared<BitCodeAbbrev>();
1000   Abbv->Add(BitCodeAbbrevOp(bitc::TYPE_CODE_FUNCTION));
1001   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isvararg
1002   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1003   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, NumBits));
1004   unsigned FunctionAbbrev = Stream.EmitAbbrev(std::move(Abbv));
1005 
1006   // Abbrev for TYPE_CODE_STRUCT_ANON.
1007   Abbv = std::make_shared<BitCodeAbbrev>();
1008   Abbv->Add(BitCodeAbbrevOp(bitc::TYPE_CODE_STRUCT_ANON));
1009   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // ispacked
1010   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1011   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, NumBits));
1012   unsigned StructAnonAbbrev = Stream.EmitAbbrev(std::move(Abbv));
1013 
1014   // Abbrev for TYPE_CODE_STRUCT_NAME.
1015   Abbv = std::make_shared<BitCodeAbbrev>();
1016   Abbv->Add(BitCodeAbbrevOp(bitc::TYPE_CODE_STRUCT_NAME));
1017   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1018   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Char6));
1019   unsigned StructNameAbbrev = Stream.EmitAbbrev(std::move(Abbv));
1020 
1021   // Abbrev for TYPE_CODE_STRUCT_NAMED.
1022   Abbv = std::make_shared<BitCodeAbbrev>();
1023   Abbv->Add(BitCodeAbbrevOp(bitc::TYPE_CODE_STRUCT_NAMED));
1024   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // ispacked
1025   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1026   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, NumBits));
1027   unsigned StructNamedAbbrev = Stream.EmitAbbrev(std::move(Abbv));
1028 
1029   // Abbrev for TYPE_CODE_ARRAY.
1030   Abbv = std::make_shared<BitCodeAbbrev>();
1031   Abbv->Add(BitCodeAbbrevOp(bitc::TYPE_CODE_ARRAY));
1032   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8)); // size
1033   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, NumBits));
1034   unsigned ArrayAbbrev = Stream.EmitAbbrev(std::move(Abbv));
1035 
1036   // Emit an entry count so the reader can reserve space.
1037   TypeVals.push_back(TypeList.size());
1038   Stream.EmitRecord(bitc::TYPE_CODE_NUMENTRY, TypeVals);
1039   TypeVals.clear();
1040 
1041   // Loop over all of the types, emitting each in turn.
1042   for (Type *T : TypeList) {
1043     int AbbrevToUse = 0;
1044     unsigned Code = 0;
1045 
1046     switch (T->getTypeID()) {
1047     case Type::BFloatTyID:
1048     case Type::X86_AMXTyID:
1049     case Type::TokenTyID:
1050       llvm_unreachable("These should never be used!!!");
1051       break;
1052     case Type::VoidTyID:
1053       Code = bitc::TYPE_CODE_VOID;
1054       break;
1055     case Type::HalfTyID:
1056       Code = bitc::TYPE_CODE_HALF;
1057       break;
1058     case Type::FloatTyID:
1059       Code = bitc::TYPE_CODE_FLOAT;
1060       break;
1061     case Type::DoubleTyID:
1062       Code = bitc::TYPE_CODE_DOUBLE;
1063       break;
1064     case Type::X86_FP80TyID:
1065       Code = bitc::TYPE_CODE_X86_FP80;
1066       break;
1067     case Type::FP128TyID:
1068       Code = bitc::TYPE_CODE_FP128;
1069       break;
1070     case Type::PPC_FP128TyID:
1071       Code = bitc::TYPE_CODE_PPC_FP128;
1072       break;
1073     case Type::LabelTyID:
1074       Code = bitc::TYPE_CODE_LABEL;
1075       break;
1076     case Type::MetadataTyID:
1077       Code = bitc::TYPE_CODE_METADATA;
1078       break;
1079     case Type::X86_MMXTyID:
1080       Code = bitc::TYPE_CODE_X86_MMX;
1081       break;
1082     case Type::IntegerTyID:
1083       // INTEGER: [width]
1084       Code = bitc::TYPE_CODE_INTEGER;
1085       TypeVals.push_back(cast<IntegerType>(T)->getBitWidth());
1086       break;
1087     case Type::TypedPointerTyID: {
1088       TypedPointerType *PTy = cast<TypedPointerType>(T);
1089       // POINTER: [pointee type, address space]
1090       Code = bitc::TYPE_CODE_POINTER;
1091       TypeVals.push_back(getTypeID(PTy->getElementType()));
1092       unsigned AddressSpace = PTy->getAddressSpace();
1093       TypeVals.push_back(AddressSpace);
1094       if (AddressSpace == 0)
1095         AbbrevToUse = PtrAbbrev;
1096       break;
1097     }
1098     case Type::PointerTyID: {
1099       PointerType *PTy = cast<PointerType>(T);
1100       // POINTER: [pointee type, address space]
1101       Code = bitc::TYPE_CODE_POINTER;
1102       // Emitting an empty struct type for the opaque pointer's type allows
1103       // this to be order-independent. Non-struct types must be emitted in
1104       // bitcode before they can be referenced.
1105       if (PTy->isOpaquePointerTy()) {
1106         TypeVals.push_back(false);
1107         Code = bitc::TYPE_CODE_OPAQUE;
1108         writeStringRecord(Stream, bitc::TYPE_CODE_STRUCT_NAME,
1109                           "dxilOpaquePtrReservedName", StructNameAbbrev);
1110       } else {
1111         TypeVals.push_back(getTypeID(PTy->getNonOpaquePointerElementType()));
1112         unsigned AddressSpace = PTy->getAddressSpace();
1113         TypeVals.push_back(AddressSpace);
1114         if (AddressSpace == 0)
1115           AbbrevToUse = PtrAbbrev;
1116       }
1117       break;
1118     }
1119     case Type::FunctionTyID: {
1120       FunctionType *FT = cast<FunctionType>(T);
1121       // FUNCTION: [isvararg, retty, paramty x N]
1122       Code = bitc::TYPE_CODE_FUNCTION;
1123       TypeVals.push_back(FT->isVarArg());
1124       TypeVals.push_back(getTypeID(FT->getReturnType()));
1125       for (Type *PTy : FT->params())
1126         TypeVals.push_back(getTypeID(PTy));
1127       AbbrevToUse = FunctionAbbrev;
1128       break;
1129     }
1130     case Type::StructTyID: {
1131       StructType *ST = cast<StructType>(T);
1132       // STRUCT: [ispacked, eltty x N]
1133       TypeVals.push_back(ST->isPacked());
1134       // Output all of the element types.
1135       for (Type *ElTy : ST->elements())
1136         TypeVals.push_back(getTypeID(ElTy));
1137 
1138       if (ST->isLiteral()) {
1139         Code = bitc::TYPE_CODE_STRUCT_ANON;
1140         AbbrevToUse = StructAnonAbbrev;
1141       } else {
1142         if (ST->isOpaque()) {
1143           Code = bitc::TYPE_CODE_OPAQUE;
1144         } else {
1145           Code = bitc::TYPE_CODE_STRUCT_NAMED;
1146           AbbrevToUse = StructNamedAbbrev;
1147         }
1148 
1149         // Emit the name if it is present.
1150         if (!ST->getName().empty())
1151           writeStringRecord(Stream, bitc::TYPE_CODE_STRUCT_NAME, ST->getName(),
1152                             StructNameAbbrev);
1153       }
1154       break;
1155     }
1156     case Type::ArrayTyID: {
1157       ArrayType *AT = cast<ArrayType>(T);
1158       // ARRAY: [numelts, eltty]
1159       Code = bitc::TYPE_CODE_ARRAY;
1160       TypeVals.push_back(AT->getNumElements());
1161       TypeVals.push_back(getTypeID(AT->getElementType()));
1162       AbbrevToUse = ArrayAbbrev;
1163       break;
1164     }
1165     case Type::FixedVectorTyID:
1166     case Type::ScalableVectorTyID: {
1167       VectorType *VT = cast<VectorType>(T);
1168       // VECTOR [numelts, eltty]
1169       Code = bitc::TYPE_CODE_VECTOR;
1170       TypeVals.push_back(VT->getElementCount().getKnownMinValue());
1171       TypeVals.push_back(getTypeID(VT->getElementType()));
1172       break;
1173     }
1174     }
1175 
1176     // Emit the finished record.
1177     Stream.EmitRecord(Code, TypeVals, AbbrevToUse);
1178     TypeVals.clear();
1179   }
1180 
1181   Stream.ExitBlock();
1182 }
1183 
1184 void DXILBitcodeWriter::writeComdats() {
1185   SmallVector<uint16_t, 64> Vals;
1186   for (const Comdat *C : VE.getComdats()) {
1187     // COMDAT: [selection_kind, name]
1188     Vals.push_back(getEncodedComdatSelectionKind(*C));
1189     size_t Size = C->getName().size();
1190     assert(isUInt<16>(Size));
1191     Vals.push_back(Size);
1192     for (char Chr : C->getName())
1193       Vals.push_back((unsigned char)Chr);
1194     Stream.EmitRecord(bitc::MODULE_CODE_COMDAT, Vals, /*AbbrevToUse=*/0);
1195     Vals.clear();
1196   }
1197 }
1198 
1199 void DXILBitcodeWriter::writeValueSymbolTableForwardDecl() {}
1200 
1201 /// Emit top-level description of module, including target triple, inline asm,
1202 /// descriptors for global variables, and function prototype info.
1203 /// Returns the bit offset to backpatch with the location of the real VST.
1204 void DXILBitcodeWriter::writeModuleInfo() {
1205   // Emit various pieces of data attached to a module.
1206   if (!M.getTargetTriple().empty())
1207     writeStringRecord(Stream, bitc::MODULE_CODE_TRIPLE, M.getTargetTriple(),
1208                       0 /*TODO*/);
1209   const std::string &DL = M.getDataLayoutStr();
1210   if (!DL.empty())
1211     writeStringRecord(Stream, bitc::MODULE_CODE_DATALAYOUT, DL, 0 /*TODO*/);
1212   if (!M.getModuleInlineAsm().empty())
1213     writeStringRecord(Stream, bitc::MODULE_CODE_ASM, M.getModuleInlineAsm(),
1214                       0 /*TODO*/);
1215 
1216   // Emit information about sections and GC, computing how many there are. Also
1217   // compute the maximum alignment value.
1218   std::map<std::string, unsigned> SectionMap;
1219   std::map<std::string, unsigned> GCMap;
1220   MaybeAlign MaxAlignment;
1221   unsigned MaxGlobalType = 0;
1222   const auto UpdateMaxAlignment = [&MaxAlignment](const MaybeAlign A) {
1223     if (A)
1224       MaxAlignment = !MaxAlignment ? *A : std::max(*MaxAlignment, *A);
1225   };
1226   for (const GlobalVariable &GV : M.globals()) {
1227     UpdateMaxAlignment(GV.getAlign());
1228     // Use getGlobalObjectValueTypeID to look up the enumerated type ID for
1229     // Global Variable types.
1230     MaxGlobalType = std::max(
1231         MaxGlobalType, getGlobalObjectValueTypeID(GV.getValueType(), &GV));
1232     if (GV.hasSection()) {
1233       // Give section names unique ID's.
1234       unsigned &Entry = SectionMap[std::string(GV.getSection())];
1235       if (!Entry) {
1236         writeStringRecord(Stream, bitc::MODULE_CODE_SECTIONNAME,
1237                           GV.getSection(), 0 /*TODO*/);
1238         Entry = SectionMap.size();
1239       }
1240     }
1241   }
1242   for (const Function &F : M) {
1243     UpdateMaxAlignment(F.getAlign());
1244     if (F.hasSection()) {
1245       // Give section names unique ID's.
1246       unsigned &Entry = SectionMap[std::string(F.getSection())];
1247       if (!Entry) {
1248         writeStringRecord(Stream, bitc::MODULE_CODE_SECTIONNAME, F.getSection(),
1249                           0 /*TODO*/);
1250         Entry = SectionMap.size();
1251       }
1252     }
1253     if (F.hasGC()) {
1254       // Same for GC names.
1255       unsigned &Entry = GCMap[F.getGC()];
1256       if (!Entry) {
1257         writeStringRecord(Stream, bitc::MODULE_CODE_GCNAME, F.getGC(),
1258                           0 /*TODO*/);
1259         Entry = GCMap.size();
1260       }
1261     }
1262   }
1263 
1264   // Emit abbrev for globals, now that we know # sections and max alignment.
1265   unsigned SimpleGVarAbbrev = 0;
1266   if (!M.global_empty()) {
1267     // Add an abbrev for common globals with no visibility or thread
1268     // localness.
1269     auto Abbv = std::make_shared<BitCodeAbbrev>();
1270     Abbv->Add(BitCodeAbbrevOp(bitc::MODULE_CODE_GLOBALVAR));
1271     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
1272                               Log2_32_Ceil(MaxGlobalType + 1)));
1273     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // AddrSpace << 2
1274                                                            //| explicitType << 1
1275                                                            //| constant
1276     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // Initializer.
1277     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 5)); // Linkage.
1278     if (!MaxAlignment)                                     // Alignment.
1279       Abbv->Add(BitCodeAbbrevOp(0));
1280     else {
1281       unsigned MaxEncAlignment = getEncodedAlign(MaxAlignment);
1282       Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
1283                                 Log2_32_Ceil(MaxEncAlignment + 1)));
1284     }
1285     if (SectionMap.empty()) // Section.
1286       Abbv->Add(BitCodeAbbrevOp(0));
1287     else
1288       Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
1289                                 Log2_32_Ceil(SectionMap.size() + 1)));
1290     // Don't bother emitting vis + thread local.
1291     SimpleGVarAbbrev = Stream.EmitAbbrev(std::move(Abbv));
1292   }
1293 
1294   // Emit the global variable information.
1295   SmallVector<unsigned, 64> Vals;
1296   for (const GlobalVariable &GV : M.globals()) {
1297     unsigned AbbrevToUse = 0;
1298 
1299     // GLOBALVAR: [type, isconst, initid,
1300     //             linkage, alignment, section, visibility, threadlocal,
1301     //             unnamed_addr, externally_initialized, dllstorageclass,
1302     //             comdat]
1303     Vals.push_back(getGlobalObjectValueTypeID(GV.getValueType(), &GV));
1304     Vals.push_back(
1305         GV.getType()->getAddressSpace() << 2 | 2 |
1306         (GV.isConstant() ? 1 : 0)); // HLSL Change - bitwise | was used with
1307                                     // unsigned int and bool
1308     Vals.push_back(
1309         GV.isDeclaration() ? 0 : (VE.getValueID(GV.getInitializer()) + 1));
1310     Vals.push_back(getEncodedLinkage(GV));
1311     Vals.push_back(getEncodedAlign(GV.getAlign()));
1312     Vals.push_back(GV.hasSection() ? SectionMap[std::string(GV.getSection())]
1313                                    : 0);
1314     if (GV.isThreadLocal() ||
1315         GV.getVisibility() != GlobalValue::DefaultVisibility ||
1316         GV.getUnnamedAddr() != GlobalValue::UnnamedAddr::None ||
1317         GV.isExternallyInitialized() ||
1318         GV.getDLLStorageClass() != GlobalValue::DefaultStorageClass ||
1319         GV.hasComdat()) {
1320       Vals.push_back(getEncodedVisibility(GV));
1321       Vals.push_back(getEncodedThreadLocalMode(GV));
1322       Vals.push_back(GV.getUnnamedAddr() != GlobalValue::UnnamedAddr::None);
1323       Vals.push_back(GV.isExternallyInitialized());
1324       Vals.push_back(getEncodedDLLStorageClass(GV));
1325       Vals.push_back(GV.hasComdat() ? VE.getComdatID(GV.getComdat()) : 0);
1326     } else {
1327       AbbrevToUse = SimpleGVarAbbrev;
1328     }
1329 
1330     Stream.EmitRecord(bitc::MODULE_CODE_GLOBALVAR, Vals, AbbrevToUse);
1331     Vals.clear();
1332   }
1333 
1334   // Emit the function proto information.
1335   for (const Function &F : M) {
1336     // FUNCTION:  [type, callingconv, isproto, linkage, paramattrs, alignment,
1337     //             section, visibility, gc, unnamed_addr, prologuedata,
1338     //             dllstorageclass, comdat, prefixdata, personalityfn]
1339     Vals.push_back(getGlobalObjectValueTypeID(F.getFunctionType(), &F));
1340     Vals.push_back(F.getCallingConv());
1341     Vals.push_back(F.isDeclaration());
1342     Vals.push_back(getEncodedLinkage(F));
1343     Vals.push_back(VE.getAttributeListID(F.getAttributes()));
1344     Vals.push_back(getEncodedAlign(F.getAlign()));
1345     Vals.push_back(F.hasSection() ? SectionMap[std::string(F.getSection())]
1346                                   : 0);
1347     Vals.push_back(getEncodedVisibility(F));
1348     Vals.push_back(F.hasGC() ? GCMap[F.getGC()] : 0);
1349     Vals.push_back(F.getUnnamedAddr() != GlobalValue::UnnamedAddr::None);
1350     Vals.push_back(
1351         F.hasPrologueData() ? (VE.getValueID(F.getPrologueData()) + 1) : 0);
1352     Vals.push_back(getEncodedDLLStorageClass(F));
1353     Vals.push_back(F.hasComdat() ? VE.getComdatID(F.getComdat()) : 0);
1354     Vals.push_back(F.hasPrefixData() ? (VE.getValueID(F.getPrefixData()) + 1)
1355                                      : 0);
1356     Vals.push_back(
1357         F.hasPersonalityFn() ? (VE.getValueID(F.getPersonalityFn()) + 1) : 0);
1358 
1359     unsigned AbbrevToUse = 0;
1360     Stream.EmitRecord(bitc::MODULE_CODE_FUNCTION, Vals, AbbrevToUse);
1361     Vals.clear();
1362   }
1363 
1364   // Emit the alias information.
1365   for (const GlobalAlias &A : M.aliases()) {
1366     // ALIAS: [alias type, aliasee val#, linkage, visibility]
1367     Vals.push_back(getTypeID(A.getValueType(), &A));
1368     Vals.push_back(VE.getValueID(A.getAliasee()));
1369     Vals.push_back(getEncodedLinkage(A));
1370     Vals.push_back(getEncodedVisibility(A));
1371     Vals.push_back(getEncodedDLLStorageClass(A));
1372     Vals.push_back(getEncodedThreadLocalMode(A));
1373     Vals.push_back(A.getUnnamedAddr() != GlobalValue::UnnamedAddr::None);
1374     unsigned AbbrevToUse = 0;
1375     Stream.EmitRecord(bitc::MODULE_CODE_ALIAS_OLD, Vals, AbbrevToUse);
1376     Vals.clear();
1377   }
1378 }
1379 
1380 void DXILBitcodeWriter::writeValueAsMetadata(
1381     const ValueAsMetadata *MD, SmallVectorImpl<uint64_t> &Record) {
1382   // Mimic an MDNode with a value as one operand.
1383   Value *V = MD->getValue();
1384   Type *Ty = V->getType();
1385   if (Function *F = dyn_cast<Function>(V))
1386     Ty = TypedPointerType::get(F->getFunctionType(), F->getAddressSpace());
1387   else if (GlobalVariable *GV = dyn_cast<GlobalVariable>(V))
1388     Ty = TypedPointerType::get(GV->getValueType(), GV->getAddressSpace());
1389   Record.push_back(getTypeID(Ty));
1390   Record.push_back(VE.getValueID(V));
1391   Stream.EmitRecord(bitc::METADATA_VALUE, Record, 0);
1392   Record.clear();
1393 }
1394 
1395 void DXILBitcodeWriter::writeMDTuple(const MDTuple *N,
1396                                      SmallVectorImpl<uint64_t> &Record,
1397                                      unsigned Abbrev) {
1398   for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i) {
1399     Metadata *MD = N->getOperand(i);
1400     assert(!(MD && isa<LocalAsMetadata>(MD)) &&
1401            "Unexpected function-local metadata");
1402     Record.push_back(VE.getMetadataOrNullID(MD));
1403   }
1404   Stream.EmitRecord(N->isDistinct() ? bitc::METADATA_DISTINCT_NODE
1405                                     : bitc::METADATA_NODE,
1406                     Record, Abbrev);
1407   Record.clear();
1408 }
1409 
1410 void DXILBitcodeWriter::writeDILocation(const DILocation *N,
1411                                         SmallVectorImpl<uint64_t> &Record,
1412                                         unsigned &Abbrev) {
1413   if (!Abbrev)
1414     Abbrev = createDILocationAbbrev();
1415   Record.push_back(N->isDistinct());
1416   Record.push_back(N->getLine());
1417   Record.push_back(N->getColumn());
1418   Record.push_back(VE.getMetadataID(N->getScope()));
1419   Record.push_back(VE.getMetadataOrNullID(N->getInlinedAt()));
1420 
1421   Stream.EmitRecord(bitc::METADATA_LOCATION, Record, Abbrev);
1422   Record.clear();
1423 }
1424 
1425 static uint64_t rotateSign(APInt Val) {
1426   int64_t I = Val.getSExtValue();
1427   uint64_t U = I;
1428   return I < 0 ? ~(U << 1) : U << 1;
1429 }
1430 
1431 static uint64_t rotateSign(DISubrange::BoundType Val) {
1432   return rotateSign(Val.get<ConstantInt *>()->getValue());
1433 }
1434 
1435 void DXILBitcodeWriter::writeDISubrange(const DISubrange *N,
1436                                         SmallVectorImpl<uint64_t> &Record,
1437                                         unsigned Abbrev) {
1438   Record.push_back(N->isDistinct());
1439   Record.push_back(
1440       N->getCount().get<ConstantInt *>()->getValue().getSExtValue());
1441   Record.push_back(rotateSign(N->getLowerBound()));
1442 
1443   Stream.EmitRecord(bitc::METADATA_SUBRANGE, Record, Abbrev);
1444   Record.clear();
1445 }
1446 
1447 void DXILBitcodeWriter::writeDIEnumerator(const DIEnumerator *N,
1448                                           SmallVectorImpl<uint64_t> &Record,
1449                                           unsigned Abbrev) {
1450   Record.push_back(N->isDistinct());
1451   Record.push_back(rotateSign(N->getValue()));
1452   Record.push_back(VE.getMetadataOrNullID(N->getRawName()));
1453 
1454   Stream.EmitRecord(bitc::METADATA_ENUMERATOR, Record, Abbrev);
1455   Record.clear();
1456 }
1457 
1458 void DXILBitcodeWriter::writeDIBasicType(const DIBasicType *N,
1459                                          SmallVectorImpl<uint64_t> &Record,
1460                                          unsigned Abbrev) {
1461   Record.push_back(N->isDistinct());
1462   Record.push_back(N->getTag());
1463   Record.push_back(VE.getMetadataOrNullID(N->getRawName()));
1464   Record.push_back(N->getSizeInBits());
1465   Record.push_back(N->getAlignInBits());
1466   Record.push_back(N->getEncoding());
1467 
1468   Stream.EmitRecord(bitc::METADATA_BASIC_TYPE, Record, Abbrev);
1469   Record.clear();
1470 }
1471 
1472 void DXILBitcodeWriter::writeDIDerivedType(const DIDerivedType *N,
1473                                            SmallVectorImpl<uint64_t> &Record,
1474                                            unsigned Abbrev) {
1475   Record.push_back(N->isDistinct());
1476   Record.push_back(N->getTag());
1477   Record.push_back(VE.getMetadataOrNullID(N->getRawName()));
1478   Record.push_back(VE.getMetadataOrNullID(N->getFile()));
1479   Record.push_back(N->getLine());
1480   Record.push_back(VE.getMetadataOrNullID(N->getScope()));
1481   Record.push_back(VE.getMetadataOrNullID(N->getBaseType()));
1482   Record.push_back(N->getSizeInBits());
1483   Record.push_back(N->getAlignInBits());
1484   Record.push_back(N->getOffsetInBits());
1485   Record.push_back(N->getFlags());
1486   Record.push_back(VE.getMetadataOrNullID(N->getExtraData()));
1487 
1488   Stream.EmitRecord(bitc::METADATA_DERIVED_TYPE, Record, Abbrev);
1489   Record.clear();
1490 }
1491 
1492 void DXILBitcodeWriter::writeDICompositeType(const DICompositeType *N,
1493                                              SmallVectorImpl<uint64_t> &Record,
1494                                              unsigned Abbrev) {
1495   Record.push_back(N->isDistinct());
1496   Record.push_back(N->getTag());
1497   Record.push_back(VE.getMetadataOrNullID(N->getRawName()));
1498   Record.push_back(VE.getMetadataOrNullID(N->getFile()));
1499   Record.push_back(N->getLine());
1500   Record.push_back(VE.getMetadataOrNullID(N->getScope()));
1501   Record.push_back(VE.getMetadataOrNullID(N->getBaseType()));
1502   Record.push_back(N->getSizeInBits());
1503   Record.push_back(N->getAlignInBits());
1504   Record.push_back(N->getOffsetInBits());
1505   Record.push_back(N->getFlags());
1506   Record.push_back(VE.getMetadataOrNullID(N->getElements().get()));
1507   Record.push_back(N->getRuntimeLang());
1508   Record.push_back(VE.getMetadataOrNullID(N->getVTableHolder()));
1509   Record.push_back(VE.getMetadataOrNullID(N->getTemplateParams().get()));
1510   Record.push_back(VE.getMetadataOrNullID(N->getRawIdentifier()));
1511 
1512   Stream.EmitRecord(bitc::METADATA_COMPOSITE_TYPE, Record, Abbrev);
1513   Record.clear();
1514 }
1515 
1516 void DXILBitcodeWriter::writeDISubroutineType(const DISubroutineType *N,
1517                                               SmallVectorImpl<uint64_t> &Record,
1518                                               unsigned Abbrev) {
1519   Record.push_back(N->isDistinct());
1520   Record.push_back(N->getFlags());
1521   Record.push_back(VE.getMetadataOrNullID(N->getTypeArray().get()));
1522 
1523   Stream.EmitRecord(bitc::METADATA_SUBROUTINE_TYPE, Record, Abbrev);
1524   Record.clear();
1525 }
1526 
1527 void DXILBitcodeWriter::writeDIFile(const DIFile *N,
1528                                     SmallVectorImpl<uint64_t> &Record,
1529                                     unsigned Abbrev) {
1530   Record.push_back(N->isDistinct());
1531   Record.push_back(VE.getMetadataOrNullID(N->getRawFilename()));
1532   Record.push_back(VE.getMetadataOrNullID(N->getRawDirectory()));
1533 
1534   Stream.EmitRecord(bitc::METADATA_FILE, Record, Abbrev);
1535   Record.clear();
1536 }
1537 
1538 void DXILBitcodeWriter::writeDICompileUnit(const DICompileUnit *N,
1539                                            SmallVectorImpl<uint64_t> &Record,
1540                                            unsigned Abbrev) {
1541   Record.push_back(N->isDistinct());
1542   Record.push_back(N->getSourceLanguage());
1543   Record.push_back(VE.getMetadataOrNullID(N->getFile()));
1544   Record.push_back(VE.getMetadataOrNullID(N->getRawProducer()));
1545   Record.push_back(N->isOptimized());
1546   Record.push_back(VE.getMetadataOrNullID(N->getRawFlags()));
1547   Record.push_back(N->getRuntimeVersion());
1548   Record.push_back(VE.getMetadataOrNullID(N->getRawSplitDebugFilename()));
1549   Record.push_back(N->getEmissionKind());
1550   Record.push_back(VE.getMetadataOrNullID(N->getEnumTypes().get()));
1551   Record.push_back(VE.getMetadataOrNullID(N->getRetainedTypes().get()));
1552   Record.push_back(/* subprograms */ 0);
1553   Record.push_back(VE.getMetadataOrNullID(N->getGlobalVariables().get()));
1554   Record.push_back(VE.getMetadataOrNullID(N->getImportedEntities().get()));
1555   Record.push_back(N->getDWOId());
1556 
1557   Stream.EmitRecord(bitc::METADATA_COMPILE_UNIT, Record, Abbrev);
1558   Record.clear();
1559 }
1560 
1561 void DXILBitcodeWriter::writeDISubprogram(const DISubprogram *N,
1562                                           SmallVectorImpl<uint64_t> &Record,
1563                                           unsigned Abbrev) {
1564   Record.push_back(N->isDistinct());
1565   Record.push_back(VE.getMetadataOrNullID(N->getScope()));
1566   Record.push_back(VE.getMetadataOrNullID(N->getRawName()));
1567   Record.push_back(VE.getMetadataOrNullID(N->getRawLinkageName()));
1568   Record.push_back(VE.getMetadataOrNullID(N->getFile()));
1569   Record.push_back(N->getLine());
1570   Record.push_back(VE.getMetadataOrNullID(N->getType()));
1571   Record.push_back(N->isLocalToUnit());
1572   Record.push_back(N->isDefinition());
1573   Record.push_back(N->getScopeLine());
1574   Record.push_back(VE.getMetadataOrNullID(N->getContainingType()));
1575   Record.push_back(N->getVirtuality());
1576   Record.push_back(N->getVirtualIndex());
1577   Record.push_back(N->getFlags());
1578   Record.push_back(N->isOptimized());
1579   Record.push_back(VE.getMetadataOrNullID(N->getRawUnit()));
1580   Record.push_back(VE.getMetadataOrNullID(N->getTemplateParams().get()));
1581   Record.push_back(VE.getMetadataOrNullID(N->getDeclaration()));
1582   Record.push_back(VE.getMetadataOrNullID(N->getRetainedNodes().get()));
1583 
1584   Stream.EmitRecord(bitc::METADATA_SUBPROGRAM, Record, Abbrev);
1585   Record.clear();
1586 }
1587 
1588 void DXILBitcodeWriter::writeDILexicalBlock(const DILexicalBlock *N,
1589                                             SmallVectorImpl<uint64_t> &Record,
1590                                             unsigned Abbrev) {
1591   Record.push_back(N->isDistinct());
1592   Record.push_back(VE.getMetadataOrNullID(N->getScope()));
1593   Record.push_back(VE.getMetadataOrNullID(N->getFile()));
1594   Record.push_back(N->getLine());
1595   Record.push_back(N->getColumn());
1596 
1597   Stream.EmitRecord(bitc::METADATA_LEXICAL_BLOCK, Record, Abbrev);
1598   Record.clear();
1599 }
1600 
1601 void DXILBitcodeWriter::writeDILexicalBlockFile(
1602     const DILexicalBlockFile *N, SmallVectorImpl<uint64_t> &Record,
1603     unsigned Abbrev) {
1604   Record.push_back(N->isDistinct());
1605   Record.push_back(VE.getMetadataOrNullID(N->getScope()));
1606   Record.push_back(VE.getMetadataOrNullID(N->getFile()));
1607   Record.push_back(N->getDiscriminator());
1608 
1609   Stream.EmitRecord(bitc::METADATA_LEXICAL_BLOCK_FILE, Record, Abbrev);
1610   Record.clear();
1611 }
1612 
1613 void DXILBitcodeWriter::writeDINamespace(const DINamespace *N,
1614                                          SmallVectorImpl<uint64_t> &Record,
1615                                          unsigned Abbrev) {
1616   Record.push_back(N->isDistinct());
1617   Record.push_back(VE.getMetadataOrNullID(N->getScope()));
1618   Record.push_back(VE.getMetadataOrNullID(N->getFile()));
1619   Record.push_back(VE.getMetadataOrNullID(N->getRawName()));
1620   Record.push_back(/* line number */ 0);
1621 
1622   Stream.EmitRecord(bitc::METADATA_NAMESPACE, Record, Abbrev);
1623   Record.clear();
1624 }
1625 
1626 void DXILBitcodeWriter::writeDIModule(const DIModule *N,
1627                                       SmallVectorImpl<uint64_t> &Record,
1628                                       unsigned Abbrev) {
1629   Record.push_back(N->isDistinct());
1630   for (auto &I : N->operands())
1631     Record.push_back(VE.getMetadataOrNullID(I));
1632 
1633   Stream.EmitRecord(bitc::METADATA_MODULE, Record, Abbrev);
1634   Record.clear();
1635 }
1636 
1637 void DXILBitcodeWriter::writeDITemplateTypeParameter(
1638     const DITemplateTypeParameter *N, SmallVectorImpl<uint64_t> &Record,
1639     unsigned Abbrev) {
1640   Record.push_back(N->isDistinct());
1641   Record.push_back(VE.getMetadataOrNullID(N->getRawName()));
1642   Record.push_back(VE.getMetadataOrNullID(N->getType()));
1643 
1644   Stream.EmitRecord(bitc::METADATA_TEMPLATE_TYPE, Record, Abbrev);
1645   Record.clear();
1646 }
1647 
1648 void DXILBitcodeWriter::writeDITemplateValueParameter(
1649     const DITemplateValueParameter *N, SmallVectorImpl<uint64_t> &Record,
1650     unsigned Abbrev) {
1651   Record.push_back(N->isDistinct());
1652   Record.push_back(N->getTag());
1653   Record.push_back(VE.getMetadataOrNullID(N->getRawName()));
1654   Record.push_back(VE.getMetadataOrNullID(N->getType()));
1655   Record.push_back(VE.getMetadataOrNullID(N->getValue()));
1656 
1657   Stream.EmitRecord(bitc::METADATA_TEMPLATE_VALUE, Record, Abbrev);
1658   Record.clear();
1659 }
1660 
1661 void DXILBitcodeWriter::writeDIGlobalVariable(const DIGlobalVariable *N,
1662                                               SmallVectorImpl<uint64_t> &Record,
1663                                               unsigned Abbrev) {
1664   Record.push_back(N->isDistinct());
1665   Record.push_back(VE.getMetadataOrNullID(N->getScope()));
1666   Record.push_back(VE.getMetadataOrNullID(N->getRawName()));
1667   Record.push_back(VE.getMetadataOrNullID(N->getRawLinkageName()));
1668   Record.push_back(VE.getMetadataOrNullID(N->getFile()));
1669   Record.push_back(N->getLine());
1670   Record.push_back(VE.getMetadataOrNullID(N->getType()));
1671   Record.push_back(N->isLocalToUnit());
1672   Record.push_back(N->isDefinition());
1673   Record.push_back(/* N->getRawVariable() */ 0);
1674   Record.push_back(VE.getMetadataOrNullID(N->getStaticDataMemberDeclaration()));
1675 
1676   Stream.EmitRecord(bitc::METADATA_GLOBAL_VAR, Record, Abbrev);
1677   Record.clear();
1678 }
1679 
1680 void DXILBitcodeWriter::writeDILocalVariable(const DILocalVariable *N,
1681                                              SmallVectorImpl<uint64_t> &Record,
1682                                              unsigned Abbrev) {
1683   Record.push_back(N->isDistinct());
1684   Record.push_back(N->getTag());
1685   Record.push_back(VE.getMetadataOrNullID(N->getScope()));
1686   Record.push_back(VE.getMetadataOrNullID(N->getRawName()));
1687   Record.push_back(VE.getMetadataOrNullID(N->getFile()));
1688   Record.push_back(N->getLine());
1689   Record.push_back(VE.getMetadataOrNullID(N->getType()));
1690   Record.push_back(N->getArg());
1691   Record.push_back(N->getFlags());
1692 
1693   Stream.EmitRecord(bitc::METADATA_LOCAL_VAR, Record, Abbrev);
1694   Record.clear();
1695 }
1696 
1697 void DXILBitcodeWriter::writeDIExpression(const DIExpression *N,
1698                                           SmallVectorImpl<uint64_t> &Record,
1699                                           unsigned Abbrev) {
1700   Record.reserve(N->getElements().size() + 1);
1701 
1702   Record.push_back(N->isDistinct());
1703   Record.append(N->elements_begin(), N->elements_end());
1704 
1705   Stream.EmitRecord(bitc::METADATA_EXPRESSION, Record, Abbrev);
1706   Record.clear();
1707 }
1708 
1709 void DXILBitcodeWriter::writeDIObjCProperty(const DIObjCProperty *N,
1710                                             SmallVectorImpl<uint64_t> &Record,
1711                                             unsigned Abbrev) {
1712   llvm_unreachable("DXIL does not support objc!!!");
1713 }
1714 
1715 void DXILBitcodeWriter::writeDIImportedEntity(const DIImportedEntity *N,
1716                                               SmallVectorImpl<uint64_t> &Record,
1717                                               unsigned Abbrev) {
1718   Record.push_back(N->isDistinct());
1719   Record.push_back(N->getTag());
1720   Record.push_back(VE.getMetadataOrNullID(N->getScope()));
1721   Record.push_back(VE.getMetadataOrNullID(N->getEntity()));
1722   Record.push_back(N->getLine());
1723   Record.push_back(VE.getMetadataOrNullID(N->getRawName()));
1724 
1725   Stream.EmitRecord(bitc::METADATA_IMPORTED_ENTITY, Record, Abbrev);
1726   Record.clear();
1727 }
1728 
1729 unsigned DXILBitcodeWriter::createDILocationAbbrev() {
1730   // Abbrev for METADATA_LOCATION.
1731   //
1732   // Assume the column is usually under 128, and always output the inlined-at
1733   // location (it's never more expensive than building an array size 1).
1734   std::shared_ptr<BitCodeAbbrev> Abbv = std::make_shared<BitCodeAbbrev>();
1735   Abbv->Add(BitCodeAbbrevOp(bitc::METADATA_LOCATION));
1736   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1));
1737   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
1738   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
1739   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
1740   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
1741   return Stream.EmitAbbrev(std::move(Abbv));
1742 }
1743 
1744 unsigned DXILBitcodeWriter::createGenericDINodeAbbrev() {
1745   // Abbrev for METADATA_GENERIC_DEBUG.
1746   //
1747   // Assume the column is usually under 128, and always output the inlined-at
1748   // location (it's never more expensive than building an array size 1).
1749   std::shared_ptr<BitCodeAbbrev> Abbv = std::make_shared<BitCodeAbbrev>();
1750   Abbv->Add(BitCodeAbbrevOp(bitc::METADATA_GENERIC_DEBUG));
1751   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1));
1752   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
1753   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1));
1754   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
1755   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1756   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
1757   return Stream.EmitAbbrev(std::move(Abbv));
1758 }
1759 
1760 void DXILBitcodeWriter::writeMetadataRecords(ArrayRef<const Metadata *> MDs,
1761                                              SmallVectorImpl<uint64_t> &Record,
1762                                              std::vector<unsigned> *MDAbbrevs,
1763                                              std::vector<uint64_t> *IndexPos) {
1764   if (MDs.empty())
1765     return;
1766 
1767     // Initialize MDNode abbreviations.
1768 #define HANDLE_MDNODE_LEAF(CLASS) unsigned CLASS##Abbrev = 0;
1769 #include "llvm/IR/Metadata.def"
1770 
1771   for (const Metadata *MD : MDs) {
1772     if (IndexPos)
1773       IndexPos->push_back(Stream.GetCurrentBitNo());
1774     if (const MDNode *N = dyn_cast<MDNode>(MD)) {
1775       assert(N->isResolved() && "Expected forward references to be resolved");
1776 
1777       switch (N->getMetadataID()) {
1778       default:
1779         llvm_unreachable("Invalid MDNode subclass");
1780 #define HANDLE_MDNODE_LEAF(CLASS)                                              \
1781   case Metadata::CLASS##Kind:                                                  \
1782     if (MDAbbrevs)                                                             \
1783       write##CLASS(cast<CLASS>(N), Record,                                     \
1784                    (*MDAbbrevs)[MetadataAbbrev::CLASS##AbbrevID]);             \
1785     else                                                                       \
1786       write##CLASS(cast<CLASS>(N), Record, CLASS##Abbrev);                     \
1787     continue;
1788 #include "llvm/IR/Metadata.def"
1789       }
1790     }
1791     writeValueAsMetadata(cast<ValueAsMetadata>(MD), Record);
1792   }
1793 }
1794 
1795 unsigned DXILBitcodeWriter::createMetadataStringsAbbrev() {
1796   auto Abbv = std::make_shared<BitCodeAbbrev>();
1797   Abbv->Add(BitCodeAbbrevOp(bitc::METADATA_STRING_OLD));
1798   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1799   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 8));
1800   return Stream.EmitAbbrev(std::move(Abbv));
1801 }
1802 
1803 void DXILBitcodeWriter::writeMetadataStrings(
1804     ArrayRef<const Metadata *> Strings, SmallVectorImpl<uint64_t> &Record) {
1805   for (const Metadata *MD : Strings) {
1806     const MDString *MDS = cast<MDString>(MD);
1807     // Code: [strchar x N]
1808     Record.append(MDS->bytes_begin(), MDS->bytes_end());
1809 
1810     // Emit the finished record.
1811     Stream.EmitRecord(bitc::METADATA_STRING_OLD, Record,
1812                       createMetadataStringsAbbrev());
1813     Record.clear();
1814   }
1815 }
1816 
1817 void DXILBitcodeWriter::writeModuleMetadata() {
1818   if (!VE.hasMDs() && M.named_metadata_empty())
1819     return;
1820 
1821   Stream.EnterSubblock(bitc::METADATA_BLOCK_ID, 5);
1822 
1823   // Emit all abbrevs upfront, so that the reader can jump in the middle of the
1824   // block and load any metadata.
1825   std::vector<unsigned> MDAbbrevs;
1826 
1827   MDAbbrevs.resize(MetadataAbbrev::LastPlusOne);
1828   MDAbbrevs[MetadataAbbrev::DILocationAbbrevID] = createDILocationAbbrev();
1829   MDAbbrevs[MetadataAbbrev::GenericDINodeAbbrevID] =
1830       createGenericDINodeAbbrev();
1831 
1832   unsigned NameAbbrev = 0;
1833   if (!M.named_metadata_empty()) {
1834     // Abbrev for METADATA_NAME.
1835     std::shared_ptr<BitCodeAbbrev> Abbv = std::make_shared<BitCodeAbbrev>();
1836     Abbv->Add(BitCodeAbbrevOp(bitc::METADATA_NAME));
1837     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1838     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 8));
1839     NameAbbrev = Stream.EmitAbbrev(std::move(Abbv));
1840   }
1841 
1842   SmallVector<uint64_t, 64> Record;
1843   writeMetadataStrings(VE.getMDStrings(), Record);
1844 
1845   std::vector<uint64_t> IndexPos;
1846   IndexPos.reserve(VE.getNonMDStrings().size());
1847   writeMetadataRecords(VE.getNonMDStrings(), Record, &MDAbbrevs, &IndexPos);
1848 
1849   // Write named metadata.
1850   for (const NamedMDNode &NMD : M.named_metadata()) {
1851     // Write name.
1852     StringRef Str = NMD.getName();
1853     Record.append(Str.bytes_begin(), Str.bytes_end());
1854     Stream.EmitRecord(bitc::METADATA_NAME, Record, NameAbbrev);
1855     Record.clear();
1856 
1857     // Write named metadata operands.
1858     for (const MDNode *N : NMD.operands())
1859       Record.push_back(VE.getMetadataID(N));
1860     Stream.EmitRecord(bitc::METADATA_NAMED_NODE, Record, 0);
1861     Record.clear();
1862   }
1863 
1864   Stream.ExitBlock();
1865 }
1866 
1867 void DXILBitcodeWriter::writeFunctionMetadata(const Function &F) {
1868   if (!VE.hasMDs())
1869     return;
1870 
1871   Stream.EnterSubblock(bitc::METADATA_BLOCK_ID, 4);
1872   SmallVector<uint64_t, 64> Record;
1873   writeMetadataStrings(VE.getMDStrings(), Record);
1874   writeMetadataRecords(VE.getNonMDStrings(), Record);
1875   Stream.ExitBlock();
1876 }
1877 
1878 void DXILBitcodeWriter::writeFunctionMetadataAttachment(const Function &F) {
1879   Stream.EnterSubblock(bitc::METADATA_ATTACHMENT_ID, 3);
1880 
1881   SmallVector<uint64_t, 64> Record;
1882 
1883   // Write metadata attachments
1884   // METADATA_ATTACHMENT - [m x [value, [n x [id, mdnode]]]
1885   SmallVector<std::pair<unsigned, MDNode *>, 4> MDs;
1886   F.getAllMetadata(MDs);
1887   if (!MDs.empty()) {
1888     for (const auto &I : MDs) {
1889       Record.push_back(I.first);
1890       Record.push_back(VE.getMetadataID(I.second));
1891     }
1892     Stream.EmitRecord(bitc::METADATA_ATTACHMENT, Record, 0);
1893     Record.clear();
1894   }
1895 
1896   for (const BasicBlock &BB : F)
1897     for (const Instruction &I : BB) {
1898       MDs.clear();
1899       I.getAllMetadataOtherThanDebugLoc(MDs);
1900 
1901       // If no metadata, ignore instruction.
1902       if (MDs.empty())
1903         continue;
1904 
1905       Record.push_back(VE.getInstructionID(&I));
1906 
1907       for (unsigned i = 0, e = MDs.size(); i != e; ++i) {
1908         Record.push_back(MDs[i].first);
1909         Record.push_back(VE.getMetadataID(MDs[i].second));
1910       }
1911       Stream.EmitRecord(bitc::METADATA_ATTACHMENT, Record, 0);
1912       Record.clear();
1913     }
1914 
1915   Stream.ExitBlock();
1916 }
1917 
1918 void DXILBitcodeWriter::writeModuleMetadataKinds() {
1919   SmallVector<uint64_t, 64> Record;
1920 
1921   // Write metadata kinds
1922   // METADATA_KIND - [n x [id, name]]
1923   SmallVector<StringRef, 8> Names;
1924   M.getMDKindNames(Names);
1925 
1926   if (Names.empty())
1927     return;
1928 
1929   Stream.EnterSubblock(bitc::METADATA_BLOCK_ID, 3);
1930 
1931   for (unsigned MDKindID = 0, e = Names.size(); MDKindID != e; ++MDKindID) {
1932     Record.push_back(MDKindID);
1933     StringRef KName = Names[MDKindID];
1934     Record.append(KName.begin(), KName.end());
1935 
1936     Stream.EmitRecord(bitc::METADATA_KIND, Record, 0);
1937     Record.clear();
1938   }
1939 
1940   Stream.ExitBlock();
1941 }
1942 
1943 void DXILBitcodeWriter::writeConstants(unsigned FirstVal, unsigned LastVal,
1944                                        bool isGlobal) {
1945   if (FirstVal == LastVal)
1946     return;
1947 
1948   Stream.EnterSubblock(bitc::CONSTANTS_BLOCK_ID, 4);
1949 
1950   unsigned AggregateAbbrev = 0;
1951   unsigned String8Abbrev = 0;
1952   unsigned CString7Abbrev = 0;
1953   unsigned CString6Abbrev = 0;
1954   // If this is a constant pool for the module, emit module-specific abbrevs.
1955   if (isGlobal) {
1956     // Abbrev for CST_CODE_AGGREGATE.
1957     auto Abbv = std::make_shared<BitCodeAbbrev>();
1958     Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_AGGREGATE));
1959     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1960     Abbv->Add(
1961         BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, Log2_32_Ceil(LastVal + 1)));
1962     AggregateAbbrev = Stream.EmitAbbrev(std::move(Abbv));
1963 
1964     // Abbrev for CST_CODE_STRING.
1965     Abbv = std::make_shared<BitCodeAbbrev>();
1966     Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_STRING));
1967     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1968     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 8));
1969     String8Abbrev = Stream.EmitAbbrev(std::move(Abbv));
1970     // Abbrev for CST_CODE_CSTRING.
1971     Abbv = std::make_shared<BitCodeAbbrev>();
1972     Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_CSTRING));
1973     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1974     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 7));
1975     CString7Abbrev = Stream.EmitAbbrev(std::move(Abbv));
1976     // Abbrev for CST_CODE_CSTRING.
1977     Abbv = std::make_shared<BitCodeAbbrev>();
1978     Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_CSTRING));
1979     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1980     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Char6));
1981     CString6Abbrev = Stream.EmitAbbrev(std::move(Abbv));
1982   }
1983 
1984   SmallVector<uint64_t, 64> Record;
1985 
1986   const ValueEnumerator::ValueList &Vals = VE.getValues();
1987   Type *LastTy = nullptr;
1988   for (unsigned i = FirstVal; i != LastVal; ++i) {
1989     const Value *V = Vals[i].first;
1990     // If we need to switch types, do so now.
1991     if (V->getType() != LastTy) {
1992       LastTy = V->getType();
1993       Record.push_back(getTypeID(LastTy, V));
1994       Stream.EmitRecord(bitc::CST_CODE_SETTYPE, Record,
1995                         CONSTANTS_SETTYPE_ABBREV);
1996       Record.clear();
1997     }
1998 
1999     if (const InlineAsm *IA = dyn_cast<InlineAsm>(V)) {
2000       Record.push_back(unsigned(IA->hasSideEffects()) |
2001                        unsigned(IA->isAlignStack()) << 1 |
2002                        unsigned(IA->getDialect() & 1) << 2);
2003 
2004       // Add the asm string.
2005       const std::string &AsmStr = IA->getAsmString();
2006       Record.push_back(AsmStr.size());
2007       Record.append(AsmStr.begin(), AsmStr.end());
2008 
2009       // Add the constraint string.
2010       const std::string &ConstraintStr = IA->getConstraintString();
2011       Record.push_back(ConstraintStr.size());
2012       Record.append(ConstraintStr.begin(), ConstraintStr.end());
2013       Stream.EmitRecord(bitc::CST_CODE_INLINEASM, Record);
2014       Record.clear();
2015       continue;
2016     }
2017     const Constant *C = cast<Constant>(V);
2018     unsigned Code = -1U;
2019     unsigned AbbrevToUse = 0;
2020     if (C->isNullValue()) {
2021       Code = bitc::CST_CODE_NULL;
2022     } else if (isa<UndefValue>(C)) {
2023       Code = bitc::CST_CODE_UNDEF;
2024     } else if (const ConstantInt *IV = dyn_cast<ConstantInt>(C)) {
2025       if (IV->getBitWidth() <= 64) {
2026         uint64_t V = IV->getSExtValue();
2027         emitSignedInt64(Record, V);
2028         Code = bitc::CST_CODE_INTEGER;
2029         AbbrevToUse = CONSTANTS_INTEGER_ABBREV;
2030       } else { // Wide integers, > 64 bits in size.
2031         // We have an arbitrary precision integer value to write whose
2032         // bit width is > 64. However, in canonical unsigned integer
2033         // format it is likely that the high bits are going to be zero.
2034         // So, we only write the number of active words.
2035         unsigned NWords = IV->getValue().getActiveWords();
2036         const uint64_t *RawWords = IV->getValue().getRawData();
2037         for (unsigned i = 0; i != NWords; ++i) {
2038           emitSignedInt64(Record, RawWords[i]);
2039         }
2040         Code = bitc::CST_CODE_WIDE_INTEGER;
2041       }
2042     } else if (const ConstantFP *CFP = dyn_cast<ConstantFP>(C)) {
2043       Code = bitc::CST_CODE_FLOAT;
2044       Type *Ty = CFP->getType();
2045       if (Ty->isHalfTy() || Ty->isFloatTy() || Ty->isDoubleTy()) {
2046         Record.push_back(CFP->getValueAPF().bitcastToAPInt().getZExtValue());
2047       } else if (Ty->isX86_FP80Ty()) {
2048         // api needed to prevent premature destruction
2049         // bits are not in the same order as a normal i80 APInt, compensate.
2050         APInt api = CFP->getValueAPF().bitcastToAPInt();
2051         const uint64_t *p = api.getRawData();
2052         Record.push_back((p[1] << 48) | (p[0] >> 16));
2053         Record.push_back(p[0] & 0xffffLL);
2054       } else if (Ty->isFP128Ty() || Ty->isPPC_FP128Ty()) {
2055         APInt api = CFP->getValueAPF().bitcastToAPInt();
2056         const uint64_t *p = api.getRawData();
2057         Record.push_back(p[0]);
2058         Record.push_back(p[1]);
2059       } else {
2060         assert(0 && "Unknown FP type!");
2061       }
2062     } else if (isa<ConstantDataSequential>(C) &&
2063                cast<ConstantDataSequential>(C)->isString()) {
2064       const ConstantDataSequential *Str = cast<ConstantDataSequential>(C);
2065       // Emit constant strings specially.
2066       unsigned NumElts = Str->getNumElements();
2067       // If this is a null-terminated string, use the denser CSTRING encoding.
2068       if (Str->isCString()) {
2069         Code = bitc::CST_CODE_CSTRING;
2070         --NumElts; // Don't encode the null, which isn't allowed by char6.
2071       } else {
2072         Code = bitc::CST_CODE_STRING;
2073         AbbrevToUse = String8Abbrev;
2074       }
2075       bool isCStr7 = Code == bitc::CST_CODE_CSTRING;
2076       bool isCStrChar6 = Code == bitc::CST_CODE_CSTRING;
2077       for (unsigned i = 0; i != NumElts; ++i) {
2078         unsigned char V = Str->getElementAsInteger(i);
2079         Record.push_back(V);
2080         isCStr7 &= (V & 128) == 0;
2081         if (isCStrChar6)
2082           isCStrChar6 = BitCodeAbbrevOp::isChar6(V);
2083       }
2084 
2085       if (isCStrChar6)
2086         AbbrevToUse = CString6Abbrev;
2087       else if (isCStr7)
2088         AbbrevToUse = CString7Abbrev;
2089     } else if (const ConstantDataSequential *CDS =
2090                    dyn_cast<ConstantDataSequential>(C)) {
2091       Code = bitc::CST_CODE_DATA;
2092       Type *EltTy = CDS->getElementType();
2093       if (isa<IntegerType>(EltTy)) {
2094         for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i)
2095           Record.push_back(CDS->getElementAsInteger(i));
2096       } else if (EltTy->isFloatTy()) {
2097         for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
2098           union {
2099             float F;
2100             uint32_t I;
2101           };
2102           F = CDS->getElementAsFloat(i);
2103           Record.push_back(I);
2104         }
2105       } else {
2106         assert(EltTy->isDoubleTy() && "Unknown ConstantData element type");
2107         for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
2108           union {
2109             double F;
2110             uint64_t I;
2111           };
2112           F = CDS->getElementAsDouble(i);
2113           Record.push_back(I);
2114         }
2115       }
2116     } else if (isa<ConstantArray>(C) || isa<ConstantStruct>(C) ||
2117                isa<ConstantVector>(C)) {
2118       Code = bitc::CST_CODE_AGGREGATE;
2119       for (const Value *Op : C->operands())
2120         Record.push_back(VE.getValueID(Op));
2121       AbbrevToUse = AggregateAbbrev;
2122     } else if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(C)) {
2123       switch (CE->getOpcode()) {
2124       default:
2125         if (Instruction::isCast(CE->getOpcode())) {
2126           Code = bitc::CST_CODE_CE_CAST;
2127           Record.push_back(getEncodedCastOpcode(CE->getOpcode()));
2128           Record.push_back(
2129               getTypeID(C->getOperand(0)->getType(), C->getOperand(0)));
2130           Record.push_back(VE.getValueID(C->getOperand(0)));
2131           AbbrevToUse = CONSTANTS_CE_CAST_Abbrev;
2132         } else {
2133           assert(CE->getNumOperands() == 2 && "Unknown constant expr!");
2134           Code = bitc::CST_CODE_CE_BINOP;
2135           Record.push_back(getEncodedBinaryOpcode(CE->getOpcode()));
2136           Record.push_back(VE.getValueID(C->getOperand(0)));
2137           Record.push_back(VE.getValueID(C->getOperand(1)));
2138           uint64_t Flags = getOptimizationFlags(CE);
2139           if (Flags != 0)
2140             Record.push_back(Flags);
2141         }
2142         break;
2143       case Instruction::GetElementPtr: {
2144         Code = bitc::CST_CODE_CE_GEP;
2145         const auto *GO = cast<GEPOperator>(C);
2146         if (GO->isInBounds())
2147           Code = bitc::CST_CODE_CE_INBOUNDS_GEP;
2148         Record.push_back(getTypeID(GO->getSourceElementType()));
2149         for (unsigned i = 0, e = CE->getNumOperands(); i != e; ++i) {
2150           Record.push_back(
2151               getTypeID(C->getOperand(i)->getType(), C->getOperand(i)));
2152           Record.push_back(VE.getValueID(C->getOperand(i)));
2153         }
2154         break;
2155       }
2156       case Instruction::Select:
2157         Code = bitc::CST_CODE_CE_SELECT;
2158         Record.push_back(VE.getValueID(C->getOperand(0)));
2159         Record.push_back(VE.getValueID(C->getOperand(1)));
2160         Record.push_back(VE.getValueID(C->getOperand(2)));
2161         break;
2162       case Instruction::ExtractElement:
2163         Code = bitc::CST_CODE_CE_EXTRACTELT;
2164         Record.push_back(getTypeID(C->getOperand(0)->getType()));
2165         Record.push_back(VE.getValueID(C->getOperand(0)));
2166         Record.push_back(getTypeID(C->getOperand(1)->getType()));
2167         Record.push_back(VE.getValueID(C->getOperand(1)));
2168         break;
2169       case Instruction::InsertElement:
2170         Code = bitc::CST_CODE_CE_INSERTELT;
2171         Record.push_back(VE.getValueID(C->getOperand(0)));
2172         Record.push_back(VE.getValueID(C->getOperand(1)));
2173         Record.push_back(getTypeID(C->getOperand(2)->getType()));
2174         Record.push_back(VE.getValueID(C->getOperand(2)));
2175         break;
2176       case Instruction::ShuffleVector:
2177         // If the return type and argument types are the same, this is a
2178         // standard shufflevector instruction.  If the types are different,
2179         // then the shuffle is widening or truncating the input vectors, and
2180         // the argument type must also be encoded.
2181         if (C->getType() == C->getOperand(0)->getType()) {
2182           Code = bitc::CST_CODE_CE_SHUFFLEVEC;
2183         } else {
2184           Code = bitc::CST_CODE_CE_SHUFVEC_EX;
2185           Record.push_back(getTypeID(C->getOperand(0)->getType()));
2186         }
2187         Record.push_back(VE.getValueID(C->getOperand(0)));
2188         Record.push_back(VE.getValueID(C->getOperand(1)));
2189         Record.push_back(VE.getValueID(C->getOperand(2)));
2190         break;
2191       case Instruction::ICmp:
2192       case Instruction::FCmp:
2193         Code = bitc::CST_CODE_CE_CMP;
2194         Record.push_back(getTypeID(C->getOperand(0)->getType()));
2195         Record.push_back(VE.getValueID(C->getOperand(0)));
2196         Record.push_back(VE.getValueID(C->getOperand(1)));
2197         Record.push_back(CE->getPredicate());
2198         break;
2199       }
2200     } else if (const BlockAddress *BA = dyn_cast<BlockAddress>(C)) {
2201       Code = bitc::CST_CODE_BLOCKADDRESS;
2202       Record.push_back(getTypeID(BA->getFunction()->getType()));
2203       Record.push_back(VE.getValueID(BA->getFunction()));
2204       Record.push_back(VE.getGlobalBasicBlockID(BA->getBasicBlock()));
2205     } else {
2206 #ifndef NDEBUG
2207       C->dump();
2208 #endif
2209       llvm_unreachable("Unknown constant!");
2210     }
2211     Stream.EmitRecord(Code, Record, AbbrevToUse);
2212     Record.clear();
2213   }
2214 
2215   Stream.ExitBlock();
2216 }
2217 
2218 void DXILBitcodeWriter::writeModuleConstants() {
2219   const ValueEnumerator::ValueList &Vals = VE.getValues();
2220 
2221   // Find the first constant to emit, which is the first non-globalvalue value.
2222   // We know globalvalues have been emitted by WriteModuleInfo.
2223   for (unsigned i = 0, e = Vals.size(); i != e; ++i) {
2224     if (!isa<GlobalValue>(Vals[i].first)) {
2225       writeConstants(i, Vals.size(), true);
2226       return;
2227     }
2228   }
2229 }
2230 
2231 /// pushValueAndType - The file has to encode both the value and type id for
2232 /// many values, because we need to know what type to create for forward
2233 /// references.  However, most operands are not forward references, so this type
2234 /// field is not needed.
2235 ///
2236 /// This function adds V's value ID to Vals.  If the value ID is higher than the
2237 /// instruction ID, then it is a forward reference, and it also includes the
2238 /// type ID.  The value ID that is written is encoded relative to the InstID.
2239 bool DXILBitcodeWriter::pushValueAndType(const Value *V, unsigned InstID,
2240                                          SmallVectorImpl<unsigned> &Vals) {
2241   unsigned ValID = VE.getValueID(V);
2242   // Make encoding relative to the InstID.
2243   Vals.push_back(InstID - ValID);
2244   if (ValID >= InstID) {
2245     Vals.push_back(getTypeID(V->getType(), V));
2246     return true;
2247   }
2248   return false;
2249 }
2250 
2251 /// pushValue - Like pushValueAndType, but where the type of the value is
2252 /// omitted (perhaps it was already encoded in an earlier operand).
2253 void DXILBitcodeWriter::pushValue(const Value *V, unsigned InstID,
2254                                   SmallVectorImpl<unsigned> &Vals) {
2255   unsigned ValID = VE.getValueID(V);
2256   Vals.push_back(InstID - ValID);
2257 }
2258 
2259 void DXILBitcodeWriter::pushValueSigned(const Value *V, unsigned InstID,
2260                                         SmallVectorImpl<uint64_t> &Vals) {
2261   unsigned ValID = VE.getValueID(V);
2262   int64_t diff = ((int32_t)InstID - (int32_t)ValID);
2263   emitSignedInt64(Vals, diff);
2264 }
2265 
2266 /// WriteInstruction - Emit an instruction
2267 void DXILBitcodeWriter::writeInstruction(const Instruction &I, unsigned InstID,
2268                                          SmallVectorImpl<unsigned> &Vals) {
2269   unsigned Code = 0;
2270   unsigned AbbrevToUse = 0;
2271   VE.setInstructionID(&I);
2272   switch (I.getOpcode()) {
2273   default:
2274     if (Instruction::isCast(I.getOpcode())) {
2275       Code = bitc::FUNC_CODE_INST_CAST;
2276       if (!pushValueAndType(I.getOperand(0), InstID, Vals))
2277         AbbrevToUse = (unsigned)FUNCTION_INST_CAST_ABBREV;
2278       Vals.push_back(getTypeID(I.getType(), &I));
2279       Vals.push_back(getEncodedCastOpcode(I.getOpcode()));
2280     } else {
2281       assert(isa<BinaryOperator>(I) && "Unknown instruction!");
2282       Code = bitc::FUNC_CODE_INST_BINOP;
2283       if (!pushValueAndType(I.getOperand(0), InstID, Vals))
2284         AbbrevToUse = (unsigned)FUNCTION_INST_BINOP_ABBREV;
2285       pushValue(I.getOperand(1), InstID, Vals);
2286       Vals.push_back(getEncodedBinaryOpcode(I.getOpcode()));
2287       uint64_t Flags = getOptimizationFlags(&I);
2288       if (Flags != 0) {
2289         if (AbbrevToUse == (unsigned)FUNCTION_INST_BINOP_ABBREV)
2290           AbbrevToUse = (unsigned)FUNCTION_INST_BINOP_FLAGS_ABBREV;
2291         Vals.push_back(Flags);
2292       }
2293     }
2294     break;
2295 
2296   case Instruction::GetElementPtr: {
2297     Code = bitc::FUNC_CODE_INST_GEP;
2298     AbbrevToUse = (unsigned)FUNCTION_INST_GEP_ABBREV;
2299     auto &GEPInst = cast<GetElementPtrInst>(I);
2300     Vals.push_back(GEPInst.isInBounds());
2301     Vals.push_back(getTypeID(GEPInst.getSourceElementType()));
2302     for (unsigned i = 0, e = I.getNumOperands(); i != e; ++i)
2303       pushValueAndType(I.getOperand(i), InstID, Vals);
2304     break;
2305   }
2306   case Instruction::ExtractValue: {
2307     Code = bitc::FUNC_CODE_INST_EXTRACTVAL;
2308     pushValueAndType(I.getOperand(0), InstID, Vals);
2309     const ExtractValueInst *EVI = cast<ExtractValueInst>(&I);
2310     Vals.append(EVI->idx_begin(), EVI->idx_end());
2311     break;
2312   }
2313   case Instruction::InsertValue: {
2314     Code = bitc::FUNC_CODE_INST_INSERTVAL;
2315     pushValueAndType(I.getOperand(0), InstID, Vals);
2316     pushValueAndType(I.getOperand(1), InstID, Vals);
2317     const InsertValueInst *IVI = cast<InsertValueInst>(&I);
2318     Vals.append(IVI->idx_begin(), IVI->idx_end());
2319     break;
2320   }
2321   case Instruction::Select:
2322     Code = bitc::FUNC_CODE_INST_VSELECT;
2323     pushValueAndType(I.getOperand(1), InstID, Vals);
2324     pushValue(I.getOperand(2), InstID, Vals);
2325     pushValueAndType(I.getOperand(0), InstID, Vals);
2326     break;
2327   case Instruction::ExtractElement:
2328     Code = bitc::FUNC_CODE_INST_EXTRACTELT;
2329     pushValueAndType(I.getOperand(0), InstID, Vals);
2330     pushValueAndType(I.getOperand(1), InstID, Vals);
2331     break;
2332   case Instruction::InsertElement:
2333     Code = bitc::FUNC_CODE_INST_INSERTELT;
2334     pushValueAndType(I.getOperand(0), InstID, Vals);
2335     pushValue(I.getOperand(1), InstID, Vals);
2336     pushValueAndType(I.getOperand(2), InstID, Vals);
2337     break;
2338   case Instruction::ShuffleVector:
2339     Code = bitc::FUNC_CODE_INST_SHUFFLEVEC;
2340     pushValueAndType(I.getOperand(0), InstID, Vals);
2341     pushValue(I.getOperand(1), InstID, Vals);
2342     pushValue(cast<ShuffleVectorInst>(&I)->getShuffleMaskForBitcode(), InstID,
2343               Vals);
2344     break;
2345   case Instruction::ICmp:
2346   case Instruction::FCmp: {
2347     // compare returning Int1Ty or vector of Int1Ty
2348     Code = bitc::FUNC_CODE_INST_CMP2;
2349     pushValueAndType(I.getOperand(0), InstID, Vals);
2350     pushValue(I.getOperand(1), InstID, Vals);
2351     Vals.push_back(cast<CmpInst>(I).getPredicate());
2352     uint64_t Flags = getOptimizationFlags(&I);
2353     if (Flags != 0)
2354       Vals.push_back(Flags);
2355     break;
2356   }
2357 
2358   case Instruction::Ret: {
2359     Code = bitc::FUNC_CODE_INST_RET;
2360     unsigned NumOperands = I.getNumOperands();
2361     if (NumOperands == 0)
2362       AbbrevToUse = (unsigned)FUNCTION_INST_RET_VOID_ABBREV;
2363     else if (NumOperands == 1) {
2364       if (!pushValueAndType(I.getOperand(0), InstID, Vals))
2365         AbbrevToUse = (unsigned)FUNCTION_INST_RET_VAL_ABBREV;
2366     } else {
2367       for (unsigned i = 0, e = NumOperands; i != e; ++i)
2368         pushValueAndType(I.getOperand(i), InstID, Vals);
2369     }
2370   } break;
2371   case Instruction::Br: {
2372     Code = bitc::FUNC_CODE_INST_BR;
2373     const BranchInst &II = cast<BranchInst>(I);
2374     Vals.push_back(VE.getValueID(II.getSuccessor(0)));
2375     if (II.isConditional()) {
2376       Vals.push_back(VE.getValueID(II.getSuccessor(1)));
2377       pushValue(II.getCondition(), InstID, Vals);
2378     }
2379   } break;
2380   case Instruction::Switch: {
2381     Code = bitc::FUNC_CODE_INST_SWITCH;
2382     const SwitchInst &SI = cast<SwitchInst>(I);
2383     Vals.push_back(getTypeID(SI.getCondition()->getType()));
2384     pushValue(SI.getCondition(), InstID, Vals);
2385     Vals.push_back(VE.getValueID(SI.getDefaultDest()));
2386     for (auto Case : SI.cases()) {
2387       Vals.push_back(VE.getValueID(Case.getCaseValue()));
2388       Vals.push_back(VE.getValueID(Case.getCaseSuccessor()));
2389     }
2390   } break;
2391   case Instruction::IndirectBr:
2392     Code = bitc::FUNC_CODE_INST_INDIRECTBR;
2393     Vals.push_back(getTypeID(I.getOperand(0)->getType()));
2394     // Encode the address operand as relative, but not the basic blocks.
2395     pushValue(I.getOperand(0), InstID, Vals);
2396     for (unsigned i = 1, e = I.getNumOperands(); i != e; ++i)
2397       Vals.push_back(VE.getValueID(I.getOperand(i)));
2398     break;
2399 
2400   case Instruction::Invoke: {
2401     const InvokeInst *II = cast<InvokeInst>(&I);
2402     const Value *Callee = II->getCalledOperand();
2403     FunctionType *FTy = II->getFunctionType();
2404     Code = bitc::FUNC_CODE_INST_INVOKE;
2405 
2406     Vals.push_back(VE.getAttributeListID(II->getAttributes()));
2407     Vals.push_back(II->getCallingConv() | 1 << 13);
2408     Vals.push_back(VE.getValueID(II->getNormalDest()));
2409     Vals.push_back(VE.getValueID(II->getUnwindDest()));
2410     Vals.push_back(getTypeID(FTy));
2411     pushValueAndType(Callee, InstID, Vals);
2412 
2413     // Emit value #'s for the fixed parameters.
2414     for (unsigned i = 0, e = FTy->getNumParams(); i != e; ++i)
2415       pushValue(I.getOperand(i), InstID, Vals); // fixed param.
2416 
2417     // Emit type/value pairs for varargs params.
2418     if (FTy->isVarArg()) {
2419       for (unsigned i = FTy->getNumParams(), e = I.getNumOperands() - 3; i != e;
2420            ++i)
2421         pushValueAndType(I.getOperand(i), InstID, Vals); // vararg
2422     }
2423     break;
2424   }
2425   case Instruction::Resume:
2426     Code = bitc::FUNC_CODE_INST_RESUME;
2427     pushValueAndType(I.getOperand(0), InstID, Vals);
2428     break;
2429   case Instruction::Unreachable:
2430     Code = bitc::FUNC_CODE_INST_UNREACHABLE;
2431     AbbrevToUse = (unsigned)FUNCTION_INST_UNREACHABLE_ABBREV;
2432     break;
2433 
2434   case Instruction::PHI: {
2435     const PHINode &PN = cast<PHINode>(I);
2436     Code = bitc::FUNC_CODE_INST_PHI;
2437     // With the newer instruction encoding, forward references could give
2438     // negative valued IDs.  This is most common for PHIs, so we use
2439     // signed VBRs.
2440     SmallVector<uint64_t, 128> Vals64;
2441     Vals64.push_back(getTypeID(PN.getType()));
2442     for (unsigned i = 0, e = PN.getNumIncomingValues(); i != e; ++i) {
2443       pushValueSigned(PN.getIncomingValue(i), InstID, Vals64);
2444       Vals64.push_back(VE.getValueID(PN.getIncomingBlock(i)));
2445     }
2446     // Emit a Vals64 vector and exit.
2447     Stream.EmitRecord(Code, Vals64, AbbrevToUse);
2448     Vals64.clear();
2449     return;
2450   }
2451 
2452   case Instruction::LandingPad: {
2453     const LandingPadInst &LP = cast<LandingPadInst>(I);
2454     Code = bitc::FUNC_CODE_INST_LANDINGPAD;
2455     Vals.push_back(getTypeID(LP.getType()));
2456     Vals.push_back(LP.isCleanup());
2457     Vals.push_back(LP.getNumClauses());
2458     for (unsigned I = 0, E = LP.getNumClauses(); I != E; ++I) {
2459       if (LP.isCatch(I))
2460         Vals.push_back(LandingPadInst::Catch);
2461       else
2462         Vals.push_back(LandingPadInst::Filter);
2463       pushValueAndType(LP.getClause(I), InstID, Vals);
2464     }
2465     break;
2466   }
2467 
2468   case Instruction::Alloca: {
2469     Code = bitc::FUNC_CODE_INST_ALLOCA;
2470     const AllocaInst &AI = cast<AllocaInst>(I);
2471     Vals.push_back(getTypeID(AI.getAllocatedType()));
2472     Vals.push_back(getTypeID(I.getOperand(0)->getType()));
2473     Vals.push_back(VE.getValueID(I.getOperand(0))); // size.
2474     unsigned AlignRecord = Log2_32(AI.getAlign().value()) + 1;
2475     assert(AlignRecord < 1 << 5 && "alignment greater than 1 << 64");
2476     AlignRecord |= AI.isUsedWithInAlloca() << 5;
2477     AlignRecord |= 1 << 6;
2478     Vals.push_back(AlignRecord);
2479     break;
2480   }
2481 
2482   case Instruction::Load:
2483     if (cast<LoadInst>(I).isAtomic()) {
2484       Code = bitc::FUNC_CODE_INST_LOADATOMIC;
2485       pushValueAndType(I.getOperand(0), InstID, Vals);
2486     } else {
2487       Code = bitc::FUNC_CODE_INST_LOAD;
2488       if (!pushValueAndType(I.getOperand(0), InstID, Vals)) // ptr
2489         AbbrevToUse = (unsigned)FUNCTION_INST_LOAD_ABBREV;
2490     }
2491     Vals.push_back(getTypeID(I.getType()));
2492     Vals.push_back(Log2(cast<LoadInst>(I).getAlign()) + 1);
2493     Vals.push_back(cast<LoadInst>(I).isVolatile());
2494     if (cast<LoadInst>(I).isAtomic()) {
2495       Vals.push_back(getEncodedOrdering(cast<LoadInst>(I).getOrdering()));
2496       Vals.push_back(getEncodedSyncScopeID(cast<LoadInst>(I).getSyncScopeID()));
2497     }
2498     break;
2499   case Instruction::Store:
2500     if (cast<StoreInst>(I).isAtomic())
2501       Code = bitc::FUNC_CODE_INST_STOREATOMIC;
2502     else
2503       Code = bitc::FUNC_CODE_INST_STORE;
2504     pushValueAndType(I.getOperand(1), InstID, Vals); // ptrty + ptr
2505     pushValueAndType(I.getOperand(0), InstID, Vals); // valty + val
2506     Vals.push_back(Log2(cast<StoreInst>(I).getAlign()) + 1);
2507     Vals.push_back(cast<StoreInst>(I).isVolatile());
2508     if (cast<StoreInst>(I).isAtomic()) {
2509       Vals.push_back(getEncodedOrdering(cast<StoreInst>(I).getOrdering()));
2510       Vals.push_back(
2511           getEncodedSyncScopeID(cast<StoreInst>(I).getSyncScopeID()));
2512     }
2513     break;
2514   case Instruction::AtomicCmpXchg:
2515     Code = bitc::FUNC_CODE_INST_CMPXCHG;
2516     pushValueAndType(I.getOperand(0), InstID, Vals); // ptrty + ptr
2517     pushValueAndType(I.getOperand(1), InstID, Vals); // cmp.
2518     pushValue(I.getOperand(2), InstID, Vals);        // newval.
2519     Vals.push_back(cast<AtomicCmpXchgInst>(I).isVolatile());
2520     Vals.push_back(
2521         getEncodedOrdering(cast<AtomicCmpXchgInst>(I).getSuccessOrdering()));
2522     Vals.push_back(
2523         getEncodedSyncScopeID(cast<AtomicCmpXchgInst>(I).getSyncScopeID()));
2524     Vals.push_back(
2525         getEncodedOrdering(cast<AtomicCmpXchgInst>(I).getFailureOrdering()));
2526     Vals.push_back(cast<AtomicCmpXchgInst>(I).isWeak());
2527     break;
2528   case Instruction::AtomicRMW:
2529     Code = bitc::FUNC_CODE_INST_ATOMICRMW;
2530     pushValueAndType(I.getOperand(0), InstID, Vals); // ptrty + ptr
2531     pushValue(I.getOperand(1), InstID, Vals);        // val.
2532     Vals.push_back(
2533         getEncodedRMWOperation(cast<AtomicRMWInst>(I).getOperation()));
2534     Vals.push_back(cast<AtomicRMWInst>(I).isVolatile());
2535     Vals.push_back(getEncodedOrdering(cast<AtomicRMWInst>(I).getOrdering()));
2536     Vals.push_back(
2537         getEncodedSyncScopeID(cast<AtomicRMWInst>(I).getSyncScopeID()));
2538     break;
2539   case Instruction::Fence:
2540     Code = bitc::FUNC_CODE_INST_FENCE;
2541     Vals.push_back(getEncodedOrdering(cast<FenceInst>(I).getOrdering()));
2542     Vals.push_back(getEncodedSyncScopeID(cast<FenceInst>(I).getSyncScopeID()));
2543     break;
2544   case Instruction::Call: {
2545     const CallInst &CI = cast<CallInst>(I);
2546     FunctionType *FTy = CI.getFunctionType();
2547 
2548     Code = bitc::FUNC_CODE_INST_CALL;
2549 
2550     Vals.push_back(VE.getAttributeListID(CI.getAttributes()));
2551     Vals.push_back((CI.getCallingConv() << 1) | unsigned(CI.isTailCall()) |
2552                    unsigned(CI.isMustTailCall()) << 14 | 1 << 15);
2553     Vals.push_back(getGlobalObjectValueTypeID(FTy, CI.getCalledFunction()));
2554     pushValueAndType(CI.getCalledOperand(), InstID, Vals); // Callee
2555 
2556     // Emit value #'s for the fixed parameters.
2557     for (unsigned i = 0, e = FTy->getNumParams(); i != e; ++i) {
2558       // Check for labels (can happen with asm labels).
2559       if (FTy->getParamType(i)->isLabelTy())
2560         Vals.push_back(VE.getValueID(CI.getArgOperand(i)));
2561       else
2562         pushValue(CI.getArgOperand(i), InstID, Vals); // fixed param.
2563     }
2564 
2565     // Emit type/value pairs for varargs params.
2566     if (FTy->isVarArg()) {
2567       for (unsigned i = FTy->getNumParams(), e = CI.arg_size(); i != e; ++i)
2568         pushValueAndType(CI.getArgOperand(i), InstID, Vals); // varargs
2569     }
2570     break;
2571   }
2572   case Instruction::VAArg:
2573     Code = bitc::FUNC_CODE_INST_VAARG;
2574     Vals.push_back(getTypeID(I.getOperand(0)->getType())); // valistty
2575     pushValue(I.getOperand(0), InstID, Vals);              // valist.
2576     Vals.push_back(getTypeID(I.getType()));                // restype.
2577     break;
2578   }
2579 
2580   Stream.EmitRecord(Code, Vals, AbbrevToUse);
2581   Vals.clear();
2582 }
2583 
2584 // Emit names for globals/functions etc.
2585 void DXILBitcodeWriter::writeFunctionLevelValueSymbolTable(
2586     const ValueSymbolTable &VST) {
2587   if (VST.empty())
2588     return;
2589   Stream.EnterSubblock(bitc::VALUE_SYMTAB_BLOCK_ID, 4);
2590 
2591   SmallVector<unsigned, 64> NameVals;
2592 
2593   // HLSL Change
2594   // Read the named values from a sorted list instead of the original list
2595   // to ensure the binary is the same no matter what values ever existed.
2596   SmallVector<const ValueName *, 16> SortedTable;
2597 
2598   for (auto &VI : VST) {
2599     SortedTable.push_back(VI.second->getValueName());
2600   }
2601   // The keys are unique, so there shouldn't be stability issues.
2602   llvm::sort(SortedTable, [](const ValueName *A, const ValueName *B) {
2603     return A->first() < B->first();
2604   });
2605 
2606   for (const ValueName *SI : SortedTable) {
2607     auto &Name = *SI;
2608 
2609     // Figure out the encoding to use for the name.
2610     bool is7Bit = true;
2611     bool isChar6 = true;
2612     for (const char *C = Name.getKeyData(), *E = C + Name.getKeyLength();
2613          C != E; ++C) {
2614       if (isChar6)
2615         isChar6 = BitCodeAbbrevOp::isChar6(*C);
2616       if ((unsigned char)*C & 128) {
2617         is7Bit = false;
2618         break; // don't bother scanning the rest.
2619       }
2620     }
2621 
2622     unsigned AbbrevToUse = VST_ENTRY_8_ABBREV;
2623 
2624     // VST_ENTRY:   [valueid, namechar x N]
2625     // VST_BBENTRY: [bbid, namechar x N]
2626     unsigned Code;
2627     if (isa<BasicBlock>(SI->getValue())) {
2628       Code = bitc::VST_CODE_BBENTRY;
2629       if (isChar6)
2630         AbbrevToUse = VST_BBENTRY_6_ABBREV;
2631     } else {
2632       Code = bitc::VST_CODE_ENTRY;
2633       if (isChar6)
2634         AbbrevToUse = VST_ENTRY_6_ABBREV;
2635       else if (is7Bit)
2636         AbbrevToUse = VST_ENTRY_7_ABBREV;
2637     }
2638 
2639     NameVals.push_back(VE.getValueID(SI->getValue()));
2640     for (const char *P = Name.getKeyData(),
2641                     *E = Name.getKeyData() + Name.getKeyLength();
2642          P != E; ++P)
2643       NameVals.push_back((unsigned char)*P);
2644 
2645     // Emit the finished record.
2646     Stream.EmitRecord(Code, NameVals, AbbrevToUse);
2647     NameVals.clear();
2648   }
2649   Stream.ExitBlock();
2650 }
2651 
2652 void DXILBitcodeWriter::writeUseList(UseListOrder &&Order) {
2653   assert(Order.Shuffle.size() >= 2 && "Shuffle too small");
2654   unsigned Code;
2655   if (isa<BasicBlock>(Order.V))
2656     Code = bitc::USELIST_CODE_BB;
2657   else
2658     Code = bitc::USELIST_CODE_DEFAULT;
2659 
2660   SmallVector<uint64_t, 64> Record(Order.Shuffle.begin(), Order.Shuffle.end());
2661   Record.push_back(VE.getValueID(Order.V));
2662   Stream.EmitRecord(Code, Record);
2663 }
2664 
2665 void DXILBitcodeWriter::writeUseListBlock(const Function *F) {
2666   auto hasMore = [&]() {
2667     return !VE.UseListOrders.empty() && VE.UseListOrders.back().F == F;
2668   };
2669   if (!hasMore())
2670     // Nothing to do.
2671     return;
2672 
2673   Stream.EnterSubblock(bitc::USELIST_BLOCK_ID, 3);
2674   while (hasMore()) {
2675     writeUseList(std::move(VE.UseListOrders.back()));
2676     VE.UseListOrders.pop_back();
2677   }
2678   Stream.ExitBlock();
2679 }
2680 
2681 /// Emit a function body to the module stream.
2682 void DXILBitcodeWriter::writeFunction(const Function &F) {
2683   Stream.EnterSubblock(bitc::FUNCTION_BLOCK_ID, 4);
2684   VE.incorporateFunction(F);
2685 
2686   SmallVector<unsigned, 64> Vals;
2687 
2688   // Emit the number of basic blocks, so the reader can create them ahead of
2689   // time.
2690   Vals.push_back(VE.getBasicBlocks().size());
2691   Stream.EmitRecord(bitc::FUNC_CODE_DECLAREBLOCKS, Vals);
2692   Vals.clear();
2693 
2694   // If there are function-local constants, emit them now.
2695   unsigned CstStart, CstEnd;
2696   VE.getFunctionConstantRange(CstStart, CstEnd);
2697   writeConstants(CstStart, CstEnd, false);
2698 
2699   // If there is function-local metadata, emit it now.
2700   writeFunctionMetadata(F);
2701 
2702   // Keep a running idea of what the instruction ID is.
2703   unsigned InstID = CstEnd;
2704 
2705   bool NeedsMetadataAttachment = F.hasMetadata();
2706 
2707   DILocation *LastDL = nullptr;
2708 
2709   // Finally, emit all the instructions, in order.
2710   for (Function::const_iterator BB = F.begin(), E = F.end(); BB != E; ++BB)
2711     for (BasicBlock::const_iterator I = BB->begin(), E = BB->end(); I != E;
2712          ++I) {
2713       writeInstruction(*I, InstID, Vals);
2714 
2715       if (!I->getType()->isVoidTy())
2716         ++InstID;
2717 
2718       // If the instruction has metadata, write a metadata attachment later.
2719       NeedsMetadataAttachment |= I->hasMetadataOtherThanDebugLoc();
2720 
2721       // If the instruction has a debug location, emit it.
2722       DILocation *DL = I->getDebugLoc();
2723       if (!DL)
2724         continue;
2725 
2726       if (DL == LastDL) {
2727         // Just repeat the same debug loc as last time.
2728         Stream.EmitRecord(bitc::FUNC_CODE_DEBUG_LOC_AGAIN, Vals);
2729         continue;
2730       }
2731 
2732       Vals.push_back(DL->getLine());
2733       Vals.push_back(DL->getColumn());
2734       Vals.push_back(VE.getMetadataOrNullID(DL->getScope()));
2735       Vals.push_back(VE.getMetadataOrNullID(DL->getInlinedAt()));
2736       Stream.EmitRecord(bitc::FUNC_CODE_DEBUG_LOC, Vals);
2737       Vals.clear();
2738 
2739       LastDL = DL;
2740     }
2741 
2742   // Emit names for all the instructions etc.
2743   if (auto *Symtab = F.getValueSymbolTable())
2744     writeFunctionLevelValueSymbolTable(*Symtab);
2745 
2746   if (NeedsMetadataAttachment)
2747     writeFunctionMetadataAttachment(F);
2748 
2749   writeUseListBlock(&F);
2750   VE.purgeFunction();
2751   Stream.ExitBlock();
2752 }
2753 
2754 // Emit blockinfo, which defines the standard abbreviations etc.
2755 void DXILBitcodeWriter::writeBlockInfo() {
2756   // We only want to emit block info records for blocks that have multiple
2757   // instances: CONSTANTS_BLOCK, FUNCTION_BLOCK and VALUE_SYMTAB_BLOCK.
2758   // Other blocks can define their abbrevs inline.
2759   Stream.EnterBlockInfoBlock();
2760 
2761   { // 8-bit fixed-width VST_ENTRY/VST_BBENTRY strings.
2762     auto Abbv = std::make_shared<BitCodeAbbrev>();
2763     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3));
2764     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
2765     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
2766     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 8));
2767     if (Stream.EmitBlockInfoAbbrev(bitc::VALUE_SYMTAB_BLOCK_ID,
2768                                    std::move(Abbv)) != VST_ENTRY_8_ABBREV)
2769       assert(false && "Unexpected abbrev ordering!");
2770   }
2771 
2772   { // 7-bit fixed width VST_ENTRY strings.
2773     auto Abbv = std::make_shared<BitCodeAbbrev>();
2774     Abbv->Add(BitCodeAbbrevOp(bitc::VST_CODE_ENTRY));
2775     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
2776     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
2777     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 7));
2778     if (Stream.EmitBlockInfoAbbrev(bitc::VALUE_SYMTAB_BLOCK_ID,
2779                                    std::move(Abbv)) != VST_ENTRY_7_ABBREV)
2780       assert(false && "Unexpected abbrev ordering!");
2781   }
2782   { // 6-bit char6 VST_ENTRY strings.
2783     auto Abbv = std::make_shared<BitCodeAbbrev>();
2784     Abbv->Add(BitCodeAbbrevOp(bitc::VST_CODE_ENTRY));
2785     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
2786     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
2787     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Char6));
2788     if (Stream.EmitBlockInfoAbbrev(bitc::VALUE_SYMTAB_BLOCK_ID,
2789                                    std::move(Abbv)) != VST_ENTRY_6_ABBREV)
2790       assert(false && "Unexpected abbrev ordering!");
2791   }
2792   { // 6-bit char6 VST_BBENTRY strings.
2793     auto Abbv = std::make_shared<BitCodeAbbrev>();
2794     Abbv->Add(BitCodeAbbrevOp(bitc::VST_CODE_BBENTRY));
2795     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
2796     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
2797     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Char6));
2798     if (Stream.EmitBlockInfoAbbrev(bitc::VALUE_SYMTAB_BLOCK_ID,
2799                                    std::move(Abbv)) != VST_BBENTRY_6_ABBREV)
2800       assert(false && "Unexpected abbrev ordering!");
2801   }
2802 
2803   { // SETTYPE abbrev for CONSTANTS_BLOCK.
2804     auto Abbv = std::make_shared<BitCodeAbbrev>();
2805     Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_SETTYPE));
2806     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
2807                               VE.computeBitsRequiredForTypeIndicies()));
2808     if (Stream.EmitBlockInfoAbbrev(bitc::CONSTANTS_BLOCK_ID, std::move(Abbv)) !=
2809         CONSTANTS_SETTYPE_ABBREV)
2810       assert(false && "Unexpected abbrev ordering!");
2811   }
2812 
2813   { // INTEGER abbrev for CONSTANTS_BLOCK.
2814     auto Abbv = std::make_shared<BitCodeAbbrev>();
2815     Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_INTEGER));
2816     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
2817     if (Stream.EmitBlockInfoAbbrev(bitc::CONSTANTS_BLOCK_ID, std::move(Abbv)) !=
2818         CONSTANTS_INTEGER_ABBREV)
2819       assert(false && "Unexpected abbrev ordering!");
2820   }
2821 
2822   { // CE_CAST abbrev for CONSTANTS_BLOCK.
2823     auto Abbv = std::make_shared<BitCodeAbbrev>();
2824     Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_CE_CAST));
2825     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 4)); // cast opc
2826     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,      // typeid
2827                               VE.computeBitsRequiredForTypeIndicies()));
2828     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8)); // value id
2829 
2830     if (Stream.EmitBlockInfoAbbrev(bitc::CONSTANTS_BLOCK_ID, std::move(Abbv)) !=
2831         CONSTANTS_CE_CAST_Abbrev)
2832       assert(false && "Unexpected abbrev ordering!");
2833   }
2834   { // NULL abbrev for CONSTANTS_BLOCK.
2835     auto Abbv = std::make_shared<BitCodeAbbrev>();
2836     Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_NULL));
2837     if (Stream.EmitBlockInfoAbbrev(bitc::CONSTANTS_BLOCK_ID, std::move(Abbv)) !=
2838         CONSTANTS_NULL_Abbrev)
2839       assert(false && "Unexpected abbrev ordering!");
2840   }
2841 
2842   // FIXME: This should only use space for first class types!
2843 
2844   { // INST_LOAD abbrev for FUNCTION_BLOCK.
2845     auto Abbv = std::make_shared<BitCodeAbbrev>();
2846     Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_LOAD));
2847     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Ptr
2848     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,    // dest ty
2849                               VE.computeBitsRequiredForTypeIndicies()));
2850     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 4));   // Align
2851     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // volatile
2852     if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID, std::move(Abbv)) !=
2853         (unsigned)FUNCTION_INST_LOAD_ABBREV)
2854       assert(false && "Unexpected abbrev ordering!");
2855   }
2856   { // INST_BINOP abbrev for FUNCTION_BLOCK.
2857     auto Abbv = std::make_shared<BitCodeAbbrev>();
2858     Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_BINOP));
2859     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // LHS
2860     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // RHS
2861     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 4)); // opc
2862     if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID, std::move(Abbv)) !=
2863         (unsigned)FUNCTION_INST_BINOP_ABBREV)
2864       assert(false && "Unexpected abbrev ordering!");
2865   }
2866   { // INST_BINOP_FLAGS abbrev for FUNCTION_BLOCK.
2867     auto Abbv = std::make_shared<BitCodeAbbrev>();
2868     Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_BINOP));
2869     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // LHS
2870     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // RHS
2871     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 4)); // opc
2872     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 7)); // flags
2873     if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID, std::move(Abbv)) !=
2874         (unsigned)FUNCTION_INST_BINOP_FLAGS_ABBREV)
2875       assert(false && "Unexpected abbrev ordering!");
2876   }
2877   { // INST_CAST abbrev for FUNCTION_BLOCK.
2878     auto Abbv = std::make_shared<BitCodeAbbrev>();
2879     Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_CAST));
2880     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // OpVal
2881     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,    // dest ty
2882                               VE.computeBitsRequiredForTypeIndicies()));
2883     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 4)); // opc
2884     if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID, std::move(Abbv)) !=
2885         (unsigned)FUNCTION_INST_CAST_ABBREV)
2886       assert(false && "Unexpected abbrev ordering!");
2887   }
2888 
2889   { // INST_RET abbrev for FUNCTION_BLOCK.
2890     auto Abbv = std::make_shared<BitCodeAbbrev>();
2891     Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_RET));
2892     if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID, std::move(Abbv)) !=
2893         (unsigned)FUNCTION_INST_RET_VOID_ABBREV)
2894       assert(false && "Unexpected abbrev ordering!");
2895   }
2896   { // INST_RET abbrev for FUNCTION_BLOCK.
2897     auto Abbv = std::make_shared<BitCodeAbbrev>();
2898     Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_RET));
2899     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // ValID
2900     if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID, std::move(Abbv)) !=
2901         (unsigned)FUNCTION_INST_RET_VAL_ABBREV)
2902       assert(false && "Unexpected abbrev ordering!");
2903   }
2904   { // INST_UNREACHABLE abbrev for FUNCTION_BLOCK.
2905     auto Abbv = std::make_shared<BitCodeAbbrev>();
2906     Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_UNREACHABLE));
2907     if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID, std::move(Abbv)) !=
2908         (unsigned)FUNCTION_INST_UNREACHABLE_ABBREV)
2909       assert(false && "Unexpected abbrev ordering!");
2910   }
2911   {
2912     auto Abbv = std::make_shared<BitCodeAbbrev>();
2913     Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_GEP));
2914     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1));
2915     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, // dest ty
2916                               Log2_32_Ceil(VE.getTypes().size() + 1)));
2917     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
2918     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
2919     if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID, std::move(Abbv)) !=
2920         (unsigned)FUNCTION_INST_GEP_ABBREV)
2921       assert(false && "Unexpected abbrev ordering!");
2922   }
2923 
2924   Stream.ExitBlock();
2925 }
2926 
2927 void DXILBitcodeWriter::writeModuleVersion() {
2928   // VERSION: [version#]
2929   Stream.EmitRecord(bitc::MODULE_CODE_VERSION, ArrayRef<unsigned>{1});
2930 }
2931 
2932 /// WriteModule - Emit the specified module to the bitstream.
2933 void DXILBitcodeWriter::write() {
2934   // The identification block is new since llvm-3.7, but the old bitcode reader
2935   // will skip it.
2936   // writeIdentificationBlock(Stream);
2937 
2938   Stream.EnterSubblock(bitc::MODULE_BLOCK_ID, 3);
2939 
2940   // It is redundant to fully-specify this here, but nice to make it explicit
2941   // so that it is clear the DXIL module version is different.
2942   DXILBitcodeWriter::writeModuleVersion();
2943 
2944   // Emit blockinfo, which defines the standard abbreviations etc.
2945   writeBlockInfo();
2946 
2947   // Emit information about attribute groups.
2948   writeAttributeGroupTable();
2949 
2950   // Emit information about parameter attributes.
2951   writeAttributeTable();
2952 
2953   // Emit information describing all of the types in the module.
2954   writeTypeTable();
2955 
2956   writeComdats();
2957 
2958   // Emit top-level description of module, including target triple, inline asm,
2959   // descriptors for global variables, and function prototype info.
2960   writeModuleInfo();
2961 
2962   // Emit constants.
2963   writeModuleConstants();
2964 
2965   // Emit metadata.
2966   writeModuleMetadataKinds();
2967 
2968   // Emit metadata.
2969   writeModuleMetadata();
2970 
2971   // Emit names for globals/functions etc.
2972   // DXIL uses the same format for module-level value symbol table as for the
2973   // function level table.
2974   writeFunctionLevelValueSymbolTable(M.getValueSymbolTable());
2975 
2976   // Emit module-level use-lists.
2977   writeUseListBlock(nullptr);
2978 
2979   // Emit function bodies.
2980   for (const Function &F : M)
2981     if (!F.isDeclaration())
2982       writeFunction(F);
2983 
2984   Stream.ExitBlock();
2985 }
2986