xref: /llvm-project/llvm/lib/Target/DirectX/DXILWriter/DXILBitcodeWriter.cpp (revision ad68c66a38ec9ec93f4c178c63dc6515b58dee66)
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/ModRef.h"
53 #include "llvm/Support/SHA1.h"
54 
55 namespace llvm {
56 namespace dxil {
57 
58 // Generates an enum to use as an index in the Abbrev array of Metadata record.
59 enum MetadataAbbrev : unsigned {
60 #define HANDLE_MDNODE_LEAF(CLASS) CLASS##AbbrevID,
61 #include "llvm/IR/Metadata.def"
62   LastPlusOne
63 };
64 
65 class DXILBitcodeWriter {
66 
67   /// These are manifest constants used by the bitcode writer. They do not need
68   /// to be kept in sync with the reader, but need to be consistent within this
69   /// file.
70   enum {
71     // VALUE_SYMTAB_BLOCK abbrev id's.
72     VST_ENTRY_8_ABBREV = bitc::FIRST_APPLICATION_ABBREV,
73     VST_ENTRY_7_ABBREV,
74     VST_ENTRY_6_ABBREV,
75     VST_BBENTRY_6_ABBREV,
76 
77     // CONSTANTS_BLOCK abbrev id's.
78     CONSTANTS_SETTYPE_ABBREV = bitc::FIRST_APPLICATION_ABBREV,
79     CONSTANTS_INTEGER_ABBREV,
80     CONSTANTS_CE_CAST_Abbrev,
81     CONSTANTS_NULL_Abbrev,
82 
83     // FUNCTION_BLOCK abbrev id's.
84     FUNCTION_INST_LOAD_ABBREV = bitc::FIRST_APPLICATION_ABBREV,
85     FUNCTION_INST_BINOP_ABBREV,
86     FUNCTION_INST_BINOP_FLAGS_ABBREV,
87     FUNCTION_INST_CAST_ABBREV,
88     FUNCTION_INST_RET_VOID_ABBREV,
89     FUNCTION_INST_RET_VAL_ABBREV,
90     FUNCTION_INST_UNREACHABLE_ABBREV,
91     FUNCTION_INST_GEP_ABBREV,
92   };
93 
94   // Cache some types
95   Type *I8Ty;
96   Type *I8PtrTy;
97 
98   /// The stream created and owned by the client.
99   BitstreamWriter &Stream;
100 
101   StringTableBuilder &StrtabBuilder;
102 
103   /// The Module to write to bitcode.
104   const Module &M;
105 
106   /// Enumerates ids for all values in the module.
107   ValueEnumerator VE;
108 
109   /// Map that holds the correspondence between GUIDs in the summary index,
110   /// that came from indirect call profiles, and a value id generated by this
111   /// class to use in the VST and summary block records.
112   std::map<GlobalValue::GUID, unsigned> GUIDToValueIdMap;
113 
114   /// Tracks the last value id recorded in the GUIDToValueMap.
115   unsigned GlobalValueId;
116 
117   /// Saves the offset of the VSTOffset record that must eventually be
118   /// backpatched with the offset of the actual VST.
119   uint64_t VSTOffsetPlaceholder = 0;
120 
121   /// Pointer to the buffer allocated by caller for bitcode writing.
122   const SmallVectorImpl<char> &Buffer;
123 
124   /// The start bit of the identification block.
125   uint64_t BitcodeStartBit;
126 
127   /// This maps values to their typed pointers
128   PointerTypeMap PointerMap;
129 
130 public:
131   /// Constructs a ModuleBitcodeWriter object for the given Module,
132   /// writing to the provided \p Buffer.
133   DXILBitcodeWriter(const Module &M, SmallVectorImpl<char> &Buffer,
134                     StringTableBuilder &StrtabBuilder, BitstreamWriter &Stream)
135       : I8Ty(Type::getInt8Ty(M.getContext())),
136         I8PtrTy(TypedPointerType::get(I8Ty, 0)), Stream(Stream),
137         StrtabBuilder(StrtabBuilder), M(M), VE(M, I8PtrTy), Buffer(Buffer),
138         BitcodeStartBit(Stream.GetCurrentBitNo()),
139         PointerMap(PointerTypeAnalysis::run(M)) {
140     GlobalValueId = VE.getValues().size();
141     // Enumerate the typed pointers
142     for (auto El : PointerMap)
143       VE.EnumerateType(El.second);
144   }
145 
146   /// Emit the current module to the bitstream.
147   void write();
148 
149   static uint64_t getAttrKindEncoding(Attribute::AttrKind Kind);
150   static void writeStringRecord(BitstreamWriter &Stream, unsigned Code,
151                                 StringRef Str, unsigned AbbrevToUse);
152   static void writeIdentificationBlock(BitstreamWriter &Stream);
153   static void emitSignedInt64(SmallVectorImpl<uint64_t> &Vals, uint64_t V);
154   static void emitWideAPInt(SmallVectorImpl<uint64_t> &Vals, const APInt &A);
155 
156   static unsigned getEncodedComdatSelectionKind(const Comdat &C);
157   static unsigned getEncodedLinkage(const GlobalValue::LinkageTypes Linkage);
158   static unsigned getEncodedLinkage(const GlobalValue &GV);
159   static unsigned getEncodedVisibility(const GlobalValue &GV);
160   static unsigned getEncodedThreadLocalMode(const GlobalValue &GV);
161   static unsigned getEncodedDLLStorageClass(const GlobalValue &GV);
162   static unsigned getEncodedCastOpcode(unsigned Opcode);
163   static unsigned getEncodedUnaryOpcode(unsigned Opcode);
164   static unsigned getEncodedBinaryOpcode(unsigned Opcode);
165   static unsigned getEncodedRMWOperation(AtomicRMWInst::BinOp Op);
166   static unsigned getEncodedOrdering(AtomicOrdering Ordering);
167   static uint64_t getOptimizationFlags(const Value *V);
168 
169 private:
170   void writeModuleVersion();
171   void writePerModuleGlobalValueSummary();
172 
173   void writePerModuleFunctionSummaryRecord(SmallVector<uint64_t, 64> &NameVals,
174                                            GlobalValueSummary *Summary,
175                                            unsigned ValueID,
176                                            unsigned FSCallsAbbrev,
177                                            unsigned FSCallsProfileAbbrev,
178                                            const Function &F);
179   void writeModuleLevelReferences(const GlobalVariable &V,
180                                   SmallVector<uint64_t, 64> &NameVals,
181                                   unsigned FSModRefsAbbrev,
182                                   unsigned FSModVTableRefsAbbrev);
183 
184   void assignValueId(GlobalValue::GUID ValGUID) {
185     GUIDToValueIdMap[ValGUID] = ++GlobalValueId;
186   }
187 
188   unsigned getValueId(GlobalValue::GUID ValGUID) {
189     const auto &VMI = GUIDToValueIdMap.find(ValGUID);
190     // Expect that any GUID value had a value Id assigned by an
191     // earlier call to assignValueId.
192     assert(VMI != GUIDToValueIdMap.end() &&
193            "GUID does not have assigned value Id");
194     return VMI->second;
195   }
196 
197   // Helper to get the valueId for the type of value recorded in VI.
198   unsigned getValueId(ValueInfo VI) {
199     if (!VI.haveGVs() || !VI.getValue())
200       return getValueId(VI.getGUID());
201     return VE.getValueID(VI.getValue());
202   }
203 
204   std::map<GlobalValue::GUID, unsigned> &valueIds() { return GUIDToValueIdMap; }
205 
206   uint64_t bitcodeStartBit() { return BitcodeStartBit; }
207 
208   size_t addToStrtab(StringRef Str);
209 
210   unsigned createDILocationAbbrev();
211   unsigned createGenericDINodeAbbrev();
212 
213   void writeAttributeGroupTable();
214   void writeAttributeTable();
215   void writeTypeTable();
216   void writeComdats();
217   void writeValueSymbolTableForwardDecl();
218   void writeModuleInfo();
219   void writeValueAsMetadata(const ValueAsMetadata *MD,
220                             SmallVectorImpl<uint64_t> &Record);
221   void writeMDTuple(const MDTuple *N, SmallVectorImpl<uint64_t> &Record,
222                     unsigned Abbrev);
223   void writeDILocation(const DILocation *N, SmallVectorImpl<uint64_t> &Record,
224                        unsigned &Abbrev);
225   void writeGenericDINode(const GenericDINode *N,
226                           SmallVectorImpl<uint64_t> &Record, unsigned &Abbrev) {
227     llvm_unreachable("DXIL cannot contain GenericDI Nodes");
228   }
229   void writeDISubrange(const DISubrange *N, SmallVectorImpl<uint64_t> &Record,
230                        unsigned Abbrev);
231   void writeDIGenericSubrange(const DIGenericSubrange *N,
232                               SmallVectorImpl<uint64_t> &Record,
233                               unsigned Abbrev) {
234     llvm_unreachable("DXIL cannot contain DIGenericSubrange Nodes");
235   }
236   void writeDIEnumerator(const DIEnumerator *N,
237                          SmallVectorImpl<uint64_t> &Record, unsigned Abbrev);
238   void writeDIBasicType(const DIBasicType *N, SmallVectorImpl<uint64_t> &Record,
239                         unsigned Abbrev);
240   void writeDIStringType(const DIStringType *N,
241                          SmallVectorImpl<uint64_t> &Record, unsigned Abbrev) {
242     llvm_unreachable("DXIL cannot contain DIStringType Nodes");
243   }
244   void writeDIDerivedType(const DIDerivedType *N,
245                           SmallVectorImpl<uint64_t> &Record, unsigned Abbrev);
246   void writeDICompositeType(const DICompositeType *N,
247                             SmallVectorImpl<uint64_t> &Record, unsigned Abbrev);
248   void writeDISubroutineType(const DISubroutineType *N,
249                              SmallVectorImpl<uint64_t> &Record,
250                              unsigned Abbrev);
251   void writeDIFile(const DIFile *N, SmallVectorImpl<uint64_t> &Record,
252                    unsigned Abbrev);
253   void writeDICompileUnit(const DICompileUnit *N,
254                           SmallVectorImpl<uint64_t> &Record, unsigned Abbrev);
255   void writeDISubprogram(const DISubprogram *N,
256                          SmallVectorImpl<uint64_t> &Record, unsigned Abbrev);
257   void writeDILexicalBlock(const DILexicalBlock *N,
258                            SmallVectorImpl<uint64_t> &Record, unsigned Abbrev);
259   void writeDILexicalBlockFile(const DILexicalBlockFile *N,
260                                SmallVectorImpl<uint64_t> &Record,
261                                unsigned Abbrev);
262   void writeDICommonBlock(const DICommonBlock *N,
263                           SmallVectorImpl<uint64_t> &Record, unsigned Abbrev) {
264     llvm_unreachable("DXIL cannot contain DICommonBlock Nodes");
265   }
266   void writeDINamespace(const DINamespace *N, SmallVectorImpl<uint64_t> &Record,
267                         unsigned Abbrev);
268   void writeDIMacro(const DIMacro *N, SmallVectorImpl<uint64_t> &Record,
269                     unsigned Abbrev) {
270     llvm_unreachable("DXIL cannot contain DIMacro Nodes");
271   }
272   void writeDIMacroFile(const DIMacroFile *N, SmallVectorImpl<uint64_t> &Record,
273                         unsigned Abbrev) {
274     llvm_unreachable("DXIL cannot contain DIMacroFile Nodes");
275   }
276   void writeDIArgList(const DIArgList *N, SmallVectorImpl<uint64_t> &Record,
277                       unsigned Abbrev) {
278     llvm_unreachable("DXIL cannot contain DIArgList Nodes");
279   }
280   void writeDIAssignID(const DIAssignID *N, SmallVectorImpl<uint64_t> &Record,
281                        unsigned Abbrev) {
282     // DIAssignID is experimental feature to track variable location in IR..
283     // FIXME: translate DIAssignID to debug info DXIL supports.
284     //   See https://github.com/llvm/llvm-project/issues/58989
285     llvm_unreachable("DXIL cannot contain DIAssignID Nodes");
286   }
287   void writeDIModule(const DIModule *N, SmallVectorImpl<uint64_t> &Record,
288                      unsigned Abbrev);
289   void writeDITemplateTypeParameter(const DITemplateTypeParameter *N,
290                                     SmallVectorImpl<uint64_t> &Record,
291                                     unsigned Abbrev);
292   void writeDITemplateValueParameter(const DITemplateValueParameter *N,
293                                      SmallVectorImpl<uint64_t> &Record,
294                                      unsigned Abbrev);
295   void writeDIGlobalVariable(const DIGlobalVariable *N,
296                              SmallVectorImpl<uint64_t> &Record,
297                              unsigned Abbrev);
298   void writeDILocalVariable(const DILocalVariable *N,
299                             SmallVectorImpl<uint64_t> &Record, unsigned Abbrev);
300   void writeDILabel(const DILabel *N, SmallVectorImpl<uint64_t> &Record,
301                     unsigned Abbrev) {
302     llvm_unreachable("DXIL cannot contain DILabel Nodes");
303   }
304   void writeDIExpression(const DIExpression *N,
305                          SmallVectorImpl<uint64_t> &Record, unsigned Abbrev);
306   void writeDIGlobalVariableExpression(const DIGlobalVariableExpression *N,
307                                        SmallVectorImpl<uint64_t> &Record,
308                                        unsigned Abbrev) {
309     llvm_unreachable("DXIL cannot contain GlobalVariableExpression Nodes");
310   }
311   void writeDIObjCProperty(const DIObjCProperty *N,
312                            SmallVectorImpl<uint64_t> &Record, unsigned Abbrev);
313   void writeDIImportedEntity(const DIImportedEntity *N,
314                              SmallVectorImpl<uint64_t> &Record,
315                              unsigned Abbrev);
316   unsigned createNamedMetadataAbbrev();
317   void writeNamedMetadata(SmallVectorImpl<uint64_t> &Record);
318   unsigned createMetadataStringsAbbrev();
319   void writeMetadataStrings(ArrayRef<const Metadata *> Strings,
320                             SmallVectorImpl<uint64_t> &Record);
321   void writeMetadataRecords(ArrayRef<const Metadata *> MDs,
322                             SmallVectorImpl<uint64_t> &Record,
323                             std::vector<unsigned> *MDAbbrevs = nullptr,
324                             std::vector<uint64_t> *IndexPos = nullptr);
325   void writeModuleMetadata();
326   void writeFunctionMetadata(const Function &F);
327   void writeFunctionMetadataAttachment(const Function &F);
328   void pushGlobalMetadataAttachment(SmallVectorImpl<uint64_t> &Record,
329                                     const GlobalObject &GO);
330   void writeModuleMetadataKinds();
331   void writeOperandBundleTags();
332   void writeSyncScopeNames();
333   void writeConstants(unsigned FirstVal, unsigned LastVal, bool isGlobal);
334   void writeModuleConstants();
335   bool pushValueAndType(const Value *V, unsigned InstID,
336                         SmallVectorImpl<unsigned> &Vals);
337   void writeOperandBundles(const CallBase &CB, unsigned InstID);
338   void pushValue(const Value *V, unsigned InstID,
339                  SmallVectorImpl<unsigned> &Vals);
340   void pushValueSigned(const Value *V, unsigned InstID,
341                        SmallVectorImpl<uint64_t> &Vals);
342   void writeInstruction(const Instruction &I, unsigned InstID,
343                         SmallVectorImpl<unsigned> &Vals);
344   void writeFunctionLevelValueSymbolTable(const ValueSymbolTable &VST);
345   void writeGlobalValueSymbolTable(
346       DenseMap<const Function *, uint64_t> &FunctionToBitcodeIndex);
347   void writeUseList(UseListOrder &&Order);
348   void writeUseListBlock(const Function *F);
349   void writeFunction(const Function &F);
350   void writeBlockInfo();
351 
352   unsigned getEncodedSyncScopeID(SyncScope::ID SSID) { return unsigned(SSID); }
353 
354   unsigned getEncodedAlign(MaybeAlign Alignment) { return encode(Alignment); }
355 
356   unsigned getTypeID(Type *T, const Value *V = nullptr);
357   /// getGlobalObjectValueTypeID - returns the element type for a GlobalObject
358   ///
359   /// GlobalObject types are saved by PointerTypeAnalysis as pointers to the
360   /// GlobalObject, but in the bitcode writer we need the pointer element type.
361   unsigned getGlobalObjectValueTypeID(Type *T, const GlobalObject *G);
362 };
363 
364 } // namespace dxil
365 } // namespace llvm
366 
367 using namespace llvm;
368 using namespace llvm::dxil;
369 
370 ////////////////////////////////////////////////////////////////////////////////
371 /// Begin dxil::BitcodeWriter Implementation
372 ////////////////////////////////////////////////////////////////////////////////
373 
374 dxil::BitcodeWriter::BitcodeWriter(SmallVectorImpl<char> &Buffer,
375                                    raw_fd_stream *FS)
376     : Buffer(Buffer), Stream(new BitstreamWriter(Buffer, FS, 512)) {
377   // Emit the file header.
378   Stream->Emit((unsigned)'B', 8);
379   Stream->Emit((unsigned)'C', 8);
380   Stream->Emit(0x0, 4);
381   Stream->Emit(0xC, 4);
382   Stream->Emit(0xE, 4);
383   Stream->Emit(0xD, 4);
384 }
385 
386 dxil::BitcodeWriter::~BitcodeWriter() { assert(WroteStrtab); }
387 
388 /// Write the specified module to the specified output stream.
389 void dxil::WriteDXILToFile(const Module &M, raw_ostream &Out) {
390   SmallVector<char, 0> Buffer;
391   Buffer.reserve(256 * 1024);
392 
393   // If this is darwin or another generic macho target, reserve space for the
394   // header.
395   Triple TT(M.getTargetTriple());
396   if (TT.isOSDarwin() || TT.isOSBinFormatMachO())
397     Buffer.insert(Buffer.begin(), BWH_HeaderSize, 0);
398 
399   BitcodeWriter Writer(Buffer, dyn_cast<raw_fd_stream>(&Out));
400   Writer.writeModule(M);
401   Writer.writeSymtab();
402   Writer.writeStrtab();
403 
404   // Write the generated bitstream to "Out".
405   if (!Buffer.empty())
406     Out.write((char *)&Buffer.front(), Buffer.size());
407 }
408 
409 void BitcodeWriter::writeBlob(unsigned Block, unsigned Record, StringRef Blob) {
410   Stream->EnterSubblock(Block, 3);
411 
412   auto Abbv = std::make_shared<BitCodeAbbrev>();
413   Abbv->Add(BitCodeAbbrevOp(Record));
414   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob));
415   auto AbbrevNo = Stream->EmitAbbrev(std::move(Abbv));
416 
417   Stream->EmitRecordWithBlob(AbbrevNo, ArrayRef<uint64_t>{Record}, Blob);
418 
419   Stream->ExitBlock();
420 }
421 
422 void BitcodeWriter::writeSymtab() {
423   assert(!WroteStrtab && !WroteSymtab);
424 
425   // If any module has module-level inline asm, we will require a registered asm
426   // parser for the target so that we can create an accurate symbol table for
427   // the module.
428   for (Module *M : Mods) {
429     if (M->getModuleInlineAsm().empty())
430       continue;
431   }
432 
433   WroteSymtab = true;
434   SmallVector<char, 0> Symtab;
435   // The irsymtab::build function may be unable to create a symbol table if the
436   // module is malformed (e.g. it contains an invalid alias). Writing a symbol
437   // table is not required for correctness, but we still want to be able to
438   // write malformed modules to bitcode files, so swallow the error.
439   if (Error E = irsymtab::build(Mods, Symtab, StrtabBuilder, Alloc)) {
440     consumeError(std::move(E));
441     return;
442   }
443 
444   writeBlob(bitc::SYMTAB_BLOCK_ID, bitc::SYMTAB_BLOB,
445             {Symtab.data(), Symtab.size()});
446 }
447 
448 void BitcodeWriter::writeStrtab() {
449   assert(!WroteStrtab);
450 
451   std::vector<char> Strtab;
452   StrtabBuilder.finalizeInOrder();
453   Strtab.resize(StrtabBuilder.getSize());
454   StrtabBuilder.write((uint8_t *)Strtab.data());
455 
456   writeBlob(bitc::STRTAB_BLOCK_ID, bitc::STRTAB_BLOB,
457             {Strtab.data(), Strtab.size()});
458 
459   WroteStrtab = true;
460 }
461 
462 void BitcodeWriter::copyStrtab(StringRef Strtab) {
463   writeBlob(bitc::STRTAB_BLOCK_ID, bitc::STRTAB_BLOB, Strtab);
464   WroteStrtab = true;
465 }
466 
467 void BitcodeWriter::writeModule(const Module &M) {
468   assert(!WroteStrtab);
469 
470   // The Mods vector is used by irsymtab::build, which requires non-const
471   // Modules in case it needs to materialize metadata. But the bitcode writer
472   // requires that the module is materialized, so we can cast to non-const here,
473   // after checking that it is in fact materialized.
474   assert(M.isMaterialized());
475   Mods.push_back(const_cast<Module *>(&M));
476 
477   DXILBitcodeWriter ModuleWriter(M, Buffer, StrtabBuilder, *Stream);
478   ModuleWriter.write();
479 }
480 
481 ////////////////////////////////////////////////////////////////////////////////
482 /// Begin dxil::BitcodeWriterBase Implementation
483 ////////////////////////////////////////////////////////////////////////////////
484 
485 unsigned DXILBitcodeWriter::getEncodedCastOpcode(unsigned Opcode) {
486   switch (Opcode) {
487   default:
488     llvm_unreachable("Unknown cast instruction!");
489   case Instruction::Trunc:
490     return bitc::CAST_TRUNC;
491   case Instruction::ZExt:
492     return bitc::CAST_ZEXT;
493   case Instruction::SExt:
494     return bitc::CAST_SEXT;
495   case Instruction::FPToUI:
496     return bitc::CAST_FPTOUI;
497   case Instruction::FPToSI:
498     return bitc::CAST_FPTOSI;
499   case Instruction::UIToFP:
500     return bitc::CAST_UITOFP;
501   case Instruction::SIToFP:
502     return bitc::CAST_SITOFP;
503   case Instruction::FPTrunc:
504     return bitc::CAST_FPTRUNC;
505   case Instruction::FPExt:
506     return bitc::CAST_FPEXT;
507   case Instruction::PtrToInt:
508     return bitc::CAST_PTRTOINT;
509   case Instruction::IntToPtr:
510     return bitc::CAST_INTTOPTR;
511   case Instruction::BitCast:
512     return bitc::CAST_BITCAST;
513   case Instruction::AddrSpaceCast:
514     return bitc::CAST_ADDRSPACECAST;
515   }
516 }
517 
518 unsigned DXILBitcodeWriter::getEncodedUnaryOpcode(unsigned Opcode) {
519   switch (Opcode) {
520   default:
521     llvm_unreachable("Unknown binary instruction!");
522   case Instruction::FNeg:
523     return bitc::UNOP_FNEG;
524   }
525 }
526 
527 unsigned DXILBitcodeWriter::getEncodedBinaryOpcode(unsigned Opcode) {
528   switch (Opcode) {
529   default:
530     llvm_unreachable("Unknown binary instruction!");
531   case Instruction::Add:
532   case Instruction::FAdd:
533     return bitc::BINOP_ADD;
534   case Instruction::Sub:
535   case Instruction::FSub:
536     return bitc::BINOP_SUB;
537   case Instruction::Mul:
538   case Instruction::FMul:
539     return bitc::BINOP_MUL;
540   case Instruction::UDiv:
541     return bitc::BINOP_UDIV;
542   case Instruction::FDiv:
543   case Instruction::SDiv:
544     return bitc::BINOP_SDIV;
545   case Instruction::URem:
546     return bitc::BINOP_UREM;
547   case Instruction::FRem:
548   case Instruction::SRem:
549     return bitc::BINOP_SREM;
550   case Instruction::Shl:
551     return bitc::BINOP_SHL;
552   case Instruction::LShr:
553     return bitc::BINOP_LSHR;
554   case Instruction::AShr:
555     return bitc::BINOP_ASHR;
556   case Instruction::And:
557     return bitc::BINOP_AND;
558   case Instruction::Or:
559     return bitc::BINOP_OR;
560   case Instruction::Xor:
561     return bitc::BINOP_XOR;
562   }
563 }
564 
565 unsigned DXILBitcodeWriter::getTypeID(Type *T, const Value *V) {
566   if (!T->isOpaquePointerTy() &&
567       // For Constant, always check PointerMap to make sure OpaquePointer in
568       // things like constant struct/array works.
569       (!V || !isa<Constant>(V)))
570     return VE.getTypeID(T);
571   auto It = PointerMap.find(V);
572   if (It != PointerMap.end())
573     return VE.getTypeID(It->second);
574   // For Constant, return T when cannot find in PointerMap.
575   // FIXME: support ConstantPointerNull which could map to more than one
576   // TypedPointerType.
577   // See https://github.com/llvm/llvm-project/issues/57942.
578   if (V && isa<Constant>(V) && !isa<ConstantPointerNull>(V))
579     return VE.getTypeID(T);
580   return VE.getTypeID(I8PtrTy);
581 }
582 
583 unsigned DXILBitcodeWriter::getGlobalObjectValueTypeID(Type *T,
584                                                        const GlobalObject *G) {
585   auto It = PointerMap.find(G);
586   if (It != PointerMap.end()) {
587     TypedPointerType *PtrTy = cast<TypedPointerType>(It->second);
588     return VE.getTypeID(PtrTy->getElementType());
589   }
590   return VE.getTypeID(T);
591 }
592 
593 unsigned DXILBitcodeWriter::getEncodedRMWOperation(AtomicRMWInst::BinOp Op) {
594   switch (Op) {
595   default:
596     llvm_unreachable("Unknown RMW operation!");
597   case AtomicRMWInst::Xchg:
598     return bitc::RMW_XCHG;
599   case AtomicRMWInst::Add:
600     return bitc::RMW_ADD;
601   case AtomicRMWInst::Sub:
602     return bitc::RMW_SUB;
603   case AtomicRMWInst::And:
604     return bitc::RMW_AND;
605   case AtomicRMWInst::Nand:
606     return bitc::RMW_NAND;
607   case AtomicRMWInst::Or:
608     return bitc::RMW_OR;
609   case AtomicRMWInst::Xor:
610     return bitc::RMW_XOR;
611   case AtomicRMWInst::Max:
612     return bitc::RMW_MAX;
613   case AtomicRMWInst::Min:
614     return bitc::RMW_MIN;
615   case AtomicRMWInst::UMax:
616     return bitc::RMW_UMAX;
617   case AtomicRMWInst::UMin:
618     return bitc::RMW_UMIN;
619   case AtomicRMWInst::FAdd:
620     return bitc::RMW_FADD;
621   case AtomicRMWInst::FSub:
622     return bitc::RMW_FSUB;
623   case AtomicRMWInst::FMax:
624     return bitc::RMW_FMAX;
625   case AtomicRMWInst::FMin:
626     return bitc::RMW_FMIN;
627   }
628 }
629 
630 unsigned DXILBitcodeWriter::getEncodedOrdering(AtomicOrdering Ordering) {
631   switch (Ordering) {
632   case AtomicOrdering::NotAtomic:
633     return bitc::ORDERING_NOTATOMIC;
634   case AtomicOrdering::Unordered:
635     return bitc::ORDERING_UNORDERED;
636   case AtomicOrdering::Monotonic:
637     return bitc::ORDERING_MONOTONIC;
638   case AtomicOrdering::Acquire:
639     return bitc::ORDERING_ACQUIRE;
640   case AtomicOrdering::Release:
641     return bitc::ORDERING_RELEASE;
642   case AtomicOrdering::AcquireRelease:
643     return bitc::ORDERING_ACQREL;
644   case AtomicOrdering::SequentiallyConsistent:
645     return bitc::ORDERING_SEQCST;
646   }
647   llvm_unreachable("Invalid ordering");
648 }
649 
650 void DXILBitcodeWriter::writeStringRecord(BitstreamWriter &Stream,
651                                           unsigned Code, StringRef Str,
652                                           unsigned AbbrevToUse) {
653   SmallVector<unsigned, 64> Vals;
654 
655   // Code: [strchar x N]
656   for (char C : Str) {
657     if (AbbrevToUse && !BitCodeAbbrevOp::isChar6(C))
658       AbbrevToUse = 0;
659     Vals.push_back(C);
660   }
661 
662   // Emit the finished record.
663   Stream.EmitRecord(Code, Vals, AbbrevToUse);
664 }
665 
666 uint64_t DXILBitcodeWriter::getAttrKindEncoding(Attribute::AttrKind Kind) {
667   switch (Kind) {
668   case Attribute::Alignment:
669     return bitc::ATTR_KIND_ALIGNMENT;
670   case Attribute::AlwaysInline:
671     return bitc::ATTR_KIND_ALWAYS_INLINE;
672   case Attribute::Builtin:
673     return bitc::ATTR_KIND_BUILTIN;
674   case Attribute::ByVal:
675     return bitc::ATTR_KIND_BY_VAL;
676   case Attribute::Convergent:
677     return bitc::ATTR_KIND_CONVERGENT;
678   case Attribute::InAlloca:
679     return bitc::ATTR_KIND_IN_ALLOCA;
680   case Attribute::Cold:
681     return bitc::ATTR_KIND_COLD;
682   case Attribute::InlineHint:
683     return bitc::ATTR_KIND_INLINE_HINT;
684   case Attribute::InReg:
685     return bitc::ATTR_KIND_IN_REG;
686   case Attribute::JumpTable:
687     return bitc::ATTR_KIND_JUMP_TABLE;
688   case Attribute::MinSize:
689     return bitc::ATTR_KIND_MIN_SIZE;
690   case Attribute::Naked:
691     return bitc::ATTR_KIND_NAKED;
692   case Attribute::Nest:
693     return bitc::ATTR_KIND_NEST;
694   case Attribute::NoAlias:
695     return bitc::ATTR_KIND_NO_ALIAS;
696   case Attribute::NoBuiltin:
697     return bitc::ATTR_KIND_NO_BUILTIN;
698   case Attribute::NoCapture:
699     return bitc::ATTR_KIND_NO_CAPTURE;
700   case Attribute::NoDuplicate:
701     return bitc::ATTR_KIND_NO_DUPLICATE;
702   case Attribute::NoImplicitFloat:
703     return bitc::ATTR_KIND_NO_IMPLICIT_FLOAT;
704   case Attribute::NoInline:
705     return bitc::ATTR_KIND_NO_INLINE;
706   case Attribute::NonLazyBind:
707     return bitc::ATTR_KIND_NON_LAZY_BIND;
708   case Attribute::NonNull:
709     return bitc::ATTR_KIND_NON_NULL;
710   case Attribute::Dereferenceable:
711     return bitc::ATTR_KIND_DEREFERENCEABLE;
712   case Attribute::DereferenceableOrNull:
713     return bitc::ATTR_KIND_DEREFERENCEABLE_OR_NULL;
714   case Attribute::NoRedZone:
715     return bitc::ATTR_KIND_NO_RED_ZONE;
716   case Attribute::NoReturn:
717     return bitc::ATTR_KIND_NO_RETURN;
718   case Attribute::NoUnwind:
719     return bitc::ATTR_KIND_NO_UNWIND;
720   case Attribute::OptimizeForSize:
721     return bitc::ATTR_KIND_OPTIMIZE_FOR_SIZE;
722   case Attribute::OptimizeNone:
723     return bitc::ATTR_KIND_OPTIMIZE_NONE;
724   case Attribute::ReadNone:
725     return bitc::ATTR_KIND_READ_NONE;
726   case Attribute::ReadOnly:
727     return bitc::ATTR_KIND_READ_ONLY;
728   case Attribute::Returned:
729     return bitc::ATTR_KIND_RETURNED;
730   case Attribute::ReturnsTwice:
731     return bitc::ATTR_KIND_RETURNS_TWICE;
732   case Attribute::SExt:
733     return bitc::ATTR_KIND_S_EXT;
734   case Attribute::StackAlignment:
735     return bitc::ATTR_KIND_STACK_ALIGNMENT;
736   case Attribute::StackProtect:
737     return bitc::ATTR_KIND_STACK_PROTECT;
738   case Attribute::StackProtectReq:
739     return bitc::ATTR_KIND_STACK_PROTECT_REQ;
740   case Attribute::StackProtectStrong:
741     return bitc::ATTR_KIND_STACK_PROTECT_STRONG;
742   case Attribute::SafeStack:
743     return bitc::ATTR_KIND_SAFESTACK;
744   case Attribute::StructRet:
745     return bitc::ATTR_KIND_STRUCT_RET;
746   case Attribute::SanitizeAddress:
747     return bitc::ATTR_KIND_SANITIZE_ADDRESS;
748   case Attribute::SanitizeThread:
749     return bitc::ATTR_KIND_SANITIZE_THREAD;
750   case Attribute::SanitizeMemory:
751     return bitc::ATTR_KIND_SANITIZE_MEMORY;
752   case Attribute::UWTable:
753     return bitc::ATTR_KIND_UW_TABLE;
754   case Attribute::ZExt:
755     return bitc::ATTR_KIND_Z_EXT;
756   case Attribute::EndAttrKinds:
757     llvm_unreachable("Can not encode end-attribute kinds marker.");
758   case Attribute::None:
759     llvm_unreachable("Can not encode none-attribute.");
760   case Attribute::EmptyKey:
761   case Attribute::TombstoneKey:
762     llvm_unreachable("Trying to encode EmptyKey/TombstoneKey");
763   default:
764     llvm_unreachable("Trying to encode attribute not supported by DXIL. These "
765                      "should be stripped in DXILPrepare");
766   }
767 
768   llvm_unreachable("Trying to encode unknown attribute");
769 }
770 
771 void DXILBitcodeWriter::emitSignedInt64(SmallVectorImpl<uint64_t> &Vals,
772                                         uint64_t V) {
773   if ((int64_t)V >= 0)
774     Vals.push_back(V << 1);
775   else
776     Vals.push_back((-V << 1) | 1);
777 }
778 
779 void DXILBitcodeWriter::emitWideAPInt(SmallVectorImpl<uint64_t> &Vals,
780                                       const APInt &A) {
781   // We have an arbitrary precision integer value to write whose
782   // bit width is > 64. However, in canonical unsigned integer
783   // format it is likely that the high bits are going to be zero.
784   // So, we only write the number of active words.
785   unsigned NumWords = A.getActiveWords();
786   const uint64_t *RawData = A.getRawData();
787   for (unsigned i = 0; i < NumWords; i++)
788     emitSignedInt64(Vals, RawData[i]);
789 }
790 
791 uint64_t DXILBitcodeWriter::getOptimizationFlags(const Value *V) {
792   uint64_t Flags = 0;
793 
794   if (const auto *OBO = dyn_cast<OverflowingBinaryOperator>(V)) {
795     if (OBO->hasNoSignedWrap())
796       Flags |= 1 << bitc::OBO_NO_SIGNED_WRAP;
797     if (OBO->hasNoUnsignedWrap())
798       Flags |= 1 << bitc::OBO_NO_UNSIGNED_WRAP;
799   } else if (const auto *PEO = dyn_cast<PossiblyExactOperator>(V)) {
800     if (PEO->isExact())
801       Flags |= 1 << bitc::PEO_EXACT;
802   } else if (const auto *FPMO = dyn_cast<FPMathOperator>(V)) {
803     if (FPMO->hasAllowReassoc())
804       Flags |= bitc::AllowReassoc;
805     if (FPMO->hasNoNaNs())
806       Flags |= bitc::NoNaNs;
807     if (FPMO->hasNoInfs())
808       Flags |= bitc::NoInfs;
809     if (FPMO->hasNoSignedZeros())
810       Flags |= bitc::NoSignedZeros;
811     if (FPMO->hasAllowReciprocal())
812       Flags |= bitc::AllowReciprocal;
813     if (FPMO->hasAllowContract())
814       Flags |= bitc::AllowContract;
815     if (FPMO->hasApproxFunc())
816       Flags |= bitc::ApproxFunc;
817   }
818 
819   return Flags;
820 }
821 
822 unsigned
823 DXILBitcodeWriter::getEncodedLinkage(const GlobalValue::LinkageTypes Linkage) {
824   switch (Linkage) {
825   case GlobalValue::ExternalLinkage:
826     return 0;
827   case GlobalValue::WeakAnyLinkage:
828     return 16;
829   case GlobalValue::AppendingLinkage:
830     return 2;
831   case GlobalValue::InternalLinkage:
832     return 3;
833   case GlobalValue::LinkOnceAnyLinkage:
834     return 18;
835   case GlobalValue::ExternalWeakLinkage:
836     return 7;
837   case GlobalValue::CommonLinkage:
838     return 8;
839   case GlobalValue::PrivateLinkage:
840     return 9;
841   case GlobalValue::WeakODRLinkage:
842     return 17;
843   case GlobalValue::LinkOnceODRLinkage:
844     return 19;
845   case GlobalValue::AvailableExternallyLinkage:
846     return 12;
847   }
848   llvm_unreachable("Invalid linkage");
849 }
850 
851 unsigned DXILBitcodeWriter::getEncodedLinkage(const GlobalValue &GV) {
852   return getEncodedLinkage(GV.getLinkage());
853 }
854 
855 unsigned DXILBitcodeWriter::getEncodedVisibility(const GlobalValue &GV) {
856   switch (GV.getVisibility()) {
857   case GlobalValue::DefaultVisibility:
858     return 0;
859   case GlobalValue::HiddenVisibility:
860     return 1;
861   case GlobalValue::ProtectedVisibility:
862     return 2;
863   }
864   llvm_unreachable("Invalid visibility");
865 }
866 
867 unsigned DXILBitcodeWriter::getEncodedDLLStorageClass(const GlobalValue &GV) {
868   switch (GV.getDLLStorageClass()) {
869   case GlobalValue::DefaultStorageClass:
870     return 0;
871   case GlobalValue::DLLImportStorageClass:
872     return 1;
873   case GlobalValue::DLLExportStorageClass:
874     return 2;
875   }
876   llvm_unreachable("Invalid DLL storage class");
877 }
878 
879 unsigned DXILBitcodeWriter::getEncodedThreadLocalMode(const GlobalValue &GV) {
880   switch (GV.getThreadLocalMode()) {
881   case GlobalVariable::NotThreadLocal:
882     return 0;
883   case GlobalVariable::GeneralDynamicTLSModel:
884     return 1;
885   case GlobalVariable::LocalDynamicTLSModel:
886     return 2;
887   case GlobalVariable::InitialExecTLSModel:
888     return 3;
889   case GlobalVariable::LocalExecTLSModel:
890     return 4;
891   }
892   llvm_unreachable("Invalid TLS model");
893 }
894 
895 unsigned DXILBitcodeWriter::getEncodedComdatSelectionKind(const Comdat &C) {
896   switch (C.getSelectionKind()) {
897   case Comdat::Any:
898     return bitc::COMDAT_SELECTION_KIND_ANY;
899   case Comdat::ExactMatch:
900     return bitc::COMDAT_SELECTION_KIND_EXACT_MATCH;
901   case Comdat::Largest:
902     return bitc::COMDAT_SELECTION_KIND_LARGEST;
903   case Comdat::NoDeduplicate:
904     return bitc::COMDAT_SELECTION_KIND_NO_DUPLICATES;
905   case Comdat::SameSize:
906     return bitc::COMDAT_SELECTION_KIND_SAME_SIZE;
907   }
908   llvm_unreachable("Invalid selection kind");
909 }
910 
911 ////////////////////////////////////////////////////////////////////////////////
912 /// Begin DXILBitcodeWriter Implementation
913 ////////////////////////////////////////////////////////////////////////////////
914 
915 void DXILBitcodeWriter::writeAttributeGroupTable() {
916   const std::vector<ValueEnumerator::IndexAndAttrSet> &AttrGrps =
917       VE.getAttributeGroups();
918   if (AttrGrps.empty())
919     return;
920 
921   Stream.EnterSubblock(bitc::PARAMATTR_GROUP_BLOCK_ID, 3);
922 
923   SmallVector<uint64_t, 64> Record;
924   for (ValueEnumerator::IndexAndAttrSet Pair : AttrGrps) {
925     unsigned AttrListIndex = Pair.first;
926     AttributeSet AS = Pair.second;
927     Record.push_back(VE.getAttributeGroupID(Pair));
928     Record.push_back(AttrListIndex);
929 
930     for (Attribute Attr : AS) {
931       if (Attr.isEnumAttribute()) {
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(0);
936         Record.push_back(Val);
937       } else if (Attr.isIntAttribute()) {
938         if (Attr.getKindAsEnum() == Attribute::AttrKind::Memory) {
939           MemoryEffects ME = Attr.getMemoryEffects();
940           if (ME.doesNotAccessMemory()) {
941             Record.push_back(0);
942             Record.push_back(bitc::ATTR_KIND_READ_NONE);
943           } else {
944             if (ME.onlyReadsMemory()) {
945               Record.push_back(0);
946               Record.push_back(bitc::ATTR_KIND_READ_ONLY);
947             }
948             if (ME.onlyAccessesArgPointees()) {
949               Record.push_back(0);
950               Record.push_back(bitc::ATTR_KIND_ARGMEMONLY);
951             }
952           }
953         } else {
954           uint64_t Val = getAttrKindEncoding(Attr.getKindAsEnum());
955           assert(Val <= bitc::ATTR_KIND_ARGMEMONLY &&
956                  "DXIL does not support attributes above ATTR_KIND_ARGMEMONLY");
957           Record.push_back(1);
958           Record.push_back(Val);
959           Record.push_back(Attr.getValueAsInt());
960         }
961       } else {
962         StringRef Kind = Attr.getKindAsString();
963         StringRef Val = Attr.getValueAsString();
964 
965         Record.push_back(Val.empty() ? 3 : 4);
966         Record.append(Kind.begin(), Kind.end());
967         Record.push_back(0);
968         if (!Val.empty()) {
969           Record.append(Val.begin(), Val.end());
970           Record.push_back(0);
971         }
972       }
973     }
974 
975     Stream.EmitRecord(bitc::PARAMATTR_GRP_CODE_ENTRY, Record);
976     Record.clear();
977   }
978 
979   Stream.ExitBlock();
980 }
981 
982 void DXILBitcodeWriter::writeAttributeTable() {
983   const std::vector<AttributeList> &Attrs = VE.getAttributeLists();
984   if (Attrs.empty())
985     return;
986 
987   Stream.EnterSubblock(bitc::PARAMATTR_BLOCK_ID, 3);
988 
989   SmallVector<uint64_t, 64> Record;
990   for (unsigned i = 0, e = Attrs.size(); i != e; ++i) {
991     AttributeList AL = Attrs[i];
992     for (unsigned i : AL.indexes()) {
993       AttributeSet AS = AL.getAttributes(i);
994       if (AS.hasAttributes())
995         Record.push_back(VE.getAttributeGroupID({i, AS}));
996     }
997 
998     Stream.EmitRecord(bitc::PARAMATTR_CODE_ENTRY, Record);
999     Record.clear();
1000   }
1001 
1002   Stream.ExitBlock();
1003 }
1004 
1005 /// WriteTypeTable - Write out the type table for a module.
1006 void DXILBitcodeWriter::writeTypeTable() {
1007   const ValueEnumerator::TypeList &TypeList = VE.getTypes();
1008 
1009   Stream.EnterSubblock(bitc::TYPE_BLOCK_ID_NEW, 4 /*count from # abbrevs */);
1010   SmallVector<uint64_t, 64> TypeVals;
1011 
1012   uint64_t NumBits = VE.computeBitsRequiredForTypeIndicies();
1013 
1014   // Abbrev for TYPE_CODE_POINTER.
1015   auto Abbv = std::make_shared<BitCodeAbbrev>();
1016   Abbv->Add(BitCodeAbbrevOp(bitc::TYPE_CODE_POINTER));
1017   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, NumBits));
1018   Abbv->Add(BitCodeAbbrevOp(0)); // Addrspace = 0
1019   unsigned PtrAbbrev = Stream.EmitAbbrev(std::move(Abbv));
1020 
1021   // Abbrev for TYPE_CODE_FUNCTION.
1022   Abbv = std::make_shared<BitCodeAbbrev>();
1023   Abbv->Add(BitCodeAbbrevOp(bitc::TYPE_CODE_FUNCTION));
1024   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // isvararg
1025   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1026   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, NumBits));
1027   unsigned FunctionAbbrev = Stream.EmitAbbrev(std::move(Abbv));
1028 
1029   // Abbrev for TYPE_CODE_STRUCT_ANON.
1030   Abbv = std::make_shared<BitCodeAbbrev>();
1031   Abbv->Add(BitCodeAbbrevOp(bitc::TYPE_CODE_STRUCT_ANON));
1032   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // ispacked
1033   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1034   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, NumBits));
1035   unsigned StructAnonAbbrev = Stream.EmitAbbrev(std::move(Abbv));
1036 
1037   // Abbrev for TYPE_CODE_STRUCT_NAME.
1038   Abbv = std::make_shared<BitCodeAbbrev>();
1039   Abbv->Add(BitCodeAbbrevOp(bitc::TYPE_CODE_STRUCT_NAME));
1040   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1041   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Char6));
1042   unsigned StructNameAbbrev = Stream.EmitAbbrev(std::move(Abbv));
1043 
1044   // Abbrev for TYPE_CODE_STRUCT_NAMED.
1045   Abbv = std::make_shared<BitCodeAbbrev>();
1046   Abbv->Add(BitCodeAbbrevOp(bitc::TYPE_CODE_STRUCT_NAMED));
1047   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // ispacked
1048   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1049   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, NumBits));
1050   unsigned StructNamedAbbrev = Stream.EmitAbbrev(std::move(Abbv));
1051 
1052   // Abbrev for TYPE_CODE_ARRAY.
1053   Abbv = std::make_shared<BitCodeAbbrev>();
1054   Abbv->Add(BitCodeAbbrevOp(bitc::TYPE_CODE_ARRAY));
1055   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8)); // size
1056   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, NumBits));
1057   unsigned ArrayAbbrev = Stream.EmitAbbrev(std::move(Abbv));
1058 
1059   // Emit an entry count so the reader can reserve space.
1060   TypeVals.push_back(TypeList.size());
1061   Stream.EmitRecord(bitc::TYPE_CODE_NUMENTRY, TypeVals);
1062   TypeVals.clear();
1063 
1064   // Loop over all of the types, emitting each in turn.
1065   for (Type *T : TypeList) {
1066     int AbbrevToUse = 0;
1067     unsigned Code = 0;
1068 
1069     switch (T->getTypeID()) {
1070     case Type::BFloatTyID:
1071     case Type::X86_AMXTyID:
1072     case Type::TokenTyID:
1073       llvm_unreachable("These should never be used!!!");
1074       break;
1075     case Type::VoidTyID:
1076       Code = bitc::TYPE_CODE_VOID;
1077       break;
1078     case Type::HalfTyID:
1079       Code = bitc::TYPE_CODE_HALF;
1080       break;
1081     case Type::FloatTyID:
1082       Code = bitc::TYPE_CODE_FLOAT;
1083       break;
1084     case Type::DoubleTyID:
1085       Code = bitc::TYPE_CODE_DOUBLE;
1086       break;
1087     case Type::X86_FP80TyID:
1088       Code = bitc::TYPE_CODE_X86_FP80;
1089       break;
1090     case Type::FP128TyID:
1091       Code = bitc::TYPE_CODE_FP128;
1092       break;
1093     case Type::PPC_FP128TyID:
1094       Code = bitc::TYPE_CODE_PPC_FP128;
1095       break;
1096     case Type::LabelTyID:
1097       Code = bitc::TYPE_CODE_LABEL;
1098       break;
1099     case Type::MetadataTyID:
1100       Code = bitc::TYPE_CODE_METADATA;
1101       break;
1102     case Type::X86_MMXTyID:
1103       Code = bitc::TYPE_CODE_X86_MMX;
1104       break;
1105     case Type::IntegerTyID:
1106       // INTEGER: [width]
1107       Code = bitc::TYPE_CODE_INTEGER;
1108       TypeVals.push_back(cast<IntegerType>(T)->getBitWidth());
1109       break;
1110     case Type::TypedPointerTyID: {
1111       TypedPointerType *PTy = cast<TypedPointerType>(T);
1112       // POINTER: [pointee type, address space]
1113       Code = bitc::TYPE_CODE_POINTER;
1114       TypeVals.push_back(getTypeID(PTy->getElementType()));
1115       unsigned AddressSpace = PTy->getAddressSpace();
1116       TypeVals.push_back(AddressSpace);
1117       if (AddressSpace == 0)
1118         AbbrevToUse = PtrAbbrev;
1119       break;
1120     }
1121     case Type::PointerTyID: {
1122       PointerType *PTy = cast<PointerType>(T);
1123       // POINTER: [pointee type, address space]
1124       Code = bitc::TYPE_CODE_POINTER;
1125       // Emitting an empty struct type for the opaque pointer's type allows
1126       // this to be order-independent. Non-struct types must be emitted in
1127       // bitcode before they can be referenced.
1128       if (PTy->isOpaquePointerTy()) {
1129         TypeVals.push_back(false);
1130         Code = bitc::TYPE_CODE_OPAQUE;
1131         writeStringRecord(Stream, bitc::TYPE_CODE_STRUCT_NAME,
1132                           "dxilOpaquePtrReservedName", StructNameAbbrev);
1133       } else {
1134         TypeVals.push_back(getTypeID(PTy->getNonOpaquePointerElementType()));
1135         unsigned AddressSpace = PTy->getAddressSpace();
1136         TypeVals.push_back(AddressSpace);
1137         if (AddressSpace == 0)
1138           AbbrevToUse = PtrAbbrev;
1139       }
1140       break;
1141     }
1142     case Type::FunctionTyID: {
1143       FunctionType *FT = cast<FunctionType>(T);
1144       // FUNCTION: [isvararg, retty, paramty x N]
1145       Code = bitc::TYPE_CODE_FUNCTION;
1146       TypeVals.push_back(FT->isVarArg());
1147       TypeVals.push_back(getTypeID(FT->getReturnType()));
1148       for (Type *PTy : FT->params())
1149         TypeVals.push_back(getTypeID(PTy));
1150       AbbrevToUse = FunctionAbbrev;
1151       break;
1152     }
1153     case Type::StructTyID: {
1154       StructType *ST = cast<StructType>(T);
1155       // STRUCT: [ispacked, eltty x N]
1156       TypeVals.push_back(ST->isPacked());
1157       // Output all of the element types.
1158       for (Type *ElTy : ST->elements())
1159         TypeVals.push_back(getTypeID(ElTy));
1160 
1161       if (ST->isLiteral()) {
1162         Code = bitc::TYPE_CODE_STRUCT_ANON;
1163         AbbrevToUse = StructAnonAbbrev;
1164       } else {
1165         if (ST->isOpaque()) {
1166           Code = bitc::TYPE_CODE_OPAQUE;
1167         } else {
1168           Code = bitc::TYPE_CODE_STRUCT_NAMED;
1169           AbbrevToUse = StructNamedAbbrev;
1170         }
1171 
1172         // Emit the name if it is present.
1173         if (!ST->getName().empty())
1174           writeStringRecord(Stream, bitc::TYPE_CODE_STRUCT_NAME, ST->getName(),
1175                             StructNameAbbrev);
1176       }
1177       break;
1178     }
1179     case Type::ArrayTyID: {
1180       ArrayType *AT = cast<ArrayType>(T);
1181       // ARRAY: [numelts, eltty]
1182       Code = bitc::TYPE_CODE_ARRAY;
1183       TypeVals.push_back(AT->getNumElements());
1184       TypeVals.push_back(getTypeID(AT->getElementType()));
1185       AbbrevToUse = ArrayAbbrev;
1186       break;
1187     }
1188     case Type::FixedVectorTyID:
1189     case Type::ScalableVectorTyID: {
1190       VectorType *VT = cast<VectorType>(T);
1191       // VECTOR [numelts, eltty]
1192       Code = bitc::TYPE_CODE_VECTOR;
1193       TypeVals.push_back(VT->getElementCount().getKnownMinValue());
1194       TypeVals.push_back(getTypeID(VT->getElementType()));
1195       break;
1196     }
1197     }
1198 
1199     // Emit the finished record.
1200     Stream.EmitRecord(Code, TypeVals, AbbrevToUse);
1201     TypeVals.clear();
1202   }
1203 
1204   Stream.ExitBlock();
1205 }
1206 
1207 void DXILBitcodeWriter::writeComdats() {
1208   SmallVector<uint16_t, 64> Vals;
1209   for (const Comdat *C : VE.getComdats()) {
1210     // COMDAT: [selection_kind, name]
1211     Vals.push_back(getEncodedComdatSelectionKind(*C));
1212     size_t Size = C->getName().size();
1213     assert(isUInt<16>(Size));
1214     Vals.push_back(Size);
1215     for (char Chr : C->getName())
1216       Vals.push_back((unsigned char)Chr);
1217     Stream.EmitRecord(bitc::MODULE_CODE_COMDAT, Vals, /*AbbrevToUse=*/0);
1218     Vals.clear();
1219   }
1220 }
1221 
1222 void DXILBitcodeWriter::writeValueSymbolTableForwardDecl() {}
1223 
1224 /// Emit top-level description of module, including target triple, inline asm,
1225 /// descriptors for global variables, and function prototype info.
1226 /// Returns the bit offset to backpatch with the location of the real VST.
1227 void DXILBitcodeWriter::writeModuleInfo() {
1228   // Emit various pieces of data attached to a module.
1229   if (!M.getTargetTriple().empty())
1230     writeStringRecord(Stream, bitc::MODULE_CODE_TRIPLE, M.getTargetTriple(),
1231                       0 /*TODO*/);
1232   const std::string &DL = M.getDataLayoutStr();
1233   if (!DL.empty())
1234     writeStringRecord(Stream, bitc::MODULE_CODE_DATALAYOUT, DL, 0 /*TODO*/);
1235   if (!M.getModuleInlineAsm().empty())
1236     writeStringRecord(Stream, bitc::MODULE_CODE_ASM, M.getModuleInlineAsm(),
1237                       0 /*TODO*/);
1238 
1239   // Emit information about sections and GC, computing how many there are. Also
1240   // compute the maximum alignment value.
1241   std::map<std::string, unsigned> SectionMap;
1242   std::map<std::string, unsigned> GCMap;
1243   MaybeAlign MaxAlignment;
1244   unsigned MaxGlobalType = 0;
1245   const auto UpdateMaxAlignment = [&MaxAlignment](const MaybeAlign A) {
1246     if (A)
1247       MaxAlignment = !MaxAlignment ? *A : std::max(*MaxAlignment, *A);
1248   };
1249   for (const GlobalVariable &GV : M.globals()) {
1250     UpdateMaxAlignment(GV.getAlign());
1251     // Use getGlobalObjectValueTypeID to look up the enumerated type ID for
1252     // Global Variable types.
1253     MaxGlobalType = std::max(
1254         MaxGlobalType, getGlobalObjectValueTypeID(GV.getValueType(), &GV));
1255     if (GV.hasSection()) {
1256       // Give section names unique ID's.
1257       unsigned &Entry = SectionMap[std::string(GV.getSection())];
1258       if (!Entry) {
1259         writeStringRecord(Stream, bitc::MODULE_CODE_SECTIONNAME,
1260                           GV.getSection(), 0 /*TODO*/);
1261         Entry = SectionMap.size();
1262       }
1263     }
1264   }
1265   for (const Function &F : M) {
1266     UpdateMaxAlignment(F.getAlign());
1267     if (F.hasSection()) {
1268       // Give section names unique ID's.
1269       unsigned &Entry = SectionMap[std::string(F.getSection())];
1270       if (!Entry) {
1271         writeStringRecord(Stream, bitc::MODULE_CODE_SECTIONNAME, F.getSection(),
1272                           0 /*TODO*/);
1273         Entry = SectionMap.size();
1274       }
1275     }
1276     if (F.hasGC()) {
1277       // Same for GC names.
1278       unsigned &Entry = GCMap[F.getGC()];
1279       if (!Entry) {
1280         writeStringRecord(Stream, bitc::MODULE_CODE_GCNAME, F.getGC(),
1281                           0 /*TODO*/);
1282         Entry = GCMap.size();
1283       }
1284     }
1285   }
1286 
1287   // Emit abbrev for globals, now that we know # sections and max alignment.
1288   unsigned SimpleGVarAbbrev = 0;
1289   if (!M.global_empty()) {
1290     // Add an abbrev for common globals with no visibility or thread
1291     // localness.
1292     auto Abbv = std::make_shared<BitCodeAbbrev>();
1293     Abbv->Add(BitCodeAbbrevOp(bitc::MODULE_CODE_GLOBALVAR));
1294     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
1295                               Log2_32_Ceil(MaxGlobalType + 1)));
1296     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // AddrSpace << 2
1297                                                            //| explicitType << 1
1298                                                            //| constant
1299     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // Initializer.
1300     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 5)); // Linkage.
1301     if (!MaxAlignment)                                     // Alignment.
1302       Abbv->Add(BitCodeAbbrevOp(0));
1303     else {
1304       unsigned MaxEncAlignment = getEncodedAlign(MaxAlignment);
1305       Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
1306                                 Log2_32_Ceil(MaxEncAlignment + 1)));
1307     }
1308     if (SectionMap.empty()) // Section.
1309       Abbv->Add(BitCodeAbbrevOp(0));
1310     else
1311       Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
1312                                 Log2_32_Ceil(SectionMap.size() + 1)));
1313     // Don't bother emitting vis + thread local.
1314     SimpleGVarAbbrev = Stream.EmitAbbrev(std::move(Abbv));
1315   }
1316 
1317   // Emit the global variable information.
1318   SmallVector<unsigned, 64> Vals;
1319   for (const GlobalVariable &GV : M.globals()) {
1320     unsigned AbbrevToUse = 0;
1321 
1322     // GLOBALVAR: [type, isconst, initid,
1323     //             linkage, alignment, section, visibility, threadlocal,
1324     //             unnamed_addr, externally_initialized, dllstorageclass,
1325     //             comdat]
1326     Vals.push_back(getGlobalObjectValueTypeID(GV.getValueType(), &GV));
1327     Vals.push_back(
1328         GV.getType()->getAddressSpace() << 2 | 2 |
1329         (GV.isConstant() ? 1 : 0)); // HLSL Change - bitwise | was used with
1330                                     // unsigned int and bool
1331     Vals.push_back(
1332         GV.isDeclaration() ? 0 : (VE.getValueID(GV.getInitializer()) + 1));
1333     Vals.push_back(getEncodedLinkage(GV));
1334     Vals.push_back(getEncodedAlign(GV.getAlign()));
1335     Vals.push_back(GV.hasSection() ? SectionMap[std::string(GV.getSection())]
1336                                    : 0);
1337     if (GV.isThreadLocal() ||
1338         GV.getVisibility() != GlobalValue::DefaultVisibility ||
1339         GV.getUnnamedAddr() != GlobalValue::UnnamedAddr::None ||
1340         GV.isExternallyInitialized() ||
1341         GV.getDLLStorageClass() != GlobalValue::DefaultStorageClass ||
1342         GV.hasComdat()) {
1343       Vals.push_back(getEncodedVisibility(GV));
1344       Vals.push_back(getEncodedThreadLocalMode(GV));
1345       Vals.push_back(GV.getUnnamedAddr() != GlobalValue::UnnamedAddr::None);
1346       Vals.push_back(GV.isExternallyInitialized());
1347       Vals.push_back(getEncodedDLLStorageClass(GV));
1348       Vals.push_back(GV.hasComdat() ? VE.getComdatID(GV.getComdat()) : 0);
1349     } else {
1350       AbbrevToUse = SimpleGVarAbbrev;
1351     }
1352 
1353     Stream.EmitRecord(bitc::MODULE_CODE_GLOBALVAR, Vals, AbbrevToUse);
1354     Vals.clear();
1355   }
1356 
1357   // Emit the function proto information.
1358   for (const Function &F : M) {
1359     // FUNCTION:  [type, callingconv, isproto, linkage, paramattrs, alignment,
1360     //             section, visibility, gc, unnamed_addr, prologuedata,
1361     //             dllstorageclass, comdat, prefixdata, personalityfn]
1362     Vals.push_back(getGlobalObjectValueTypeID(F.getFunctionType(), &F));
1363     Vals.push_back(F.getCallingConv());
1364     Vals.push_back(F.isDeclaration());
1365     Vals.push_back(getEncodedLinkage(F));
1366     Vals.push_back(VE.getAttributeListID(F.getAttributes()));
1367     Vals.push_back(getEncodedAlign(F.getAlign()));
1368     Vals.push_back(F.hasSection() ? SectionMap[std::string(F.getSection())]
1369                                   : 0);
1370     Vals.push_back(getEncodedVisibility(F));
1371     Vals.push_back(F.hasGC() ? GCMap[F.getGC()] : 0);
1372     Vals.push_back(F.getUnnamedAddr() != GlobalValue::UnnamedAddr::None);
1373     Vals.push_back(
1374         F.hasPrologueData() ? (VE.getValueID(F.getPrologueData()) + 1) : 0);
1375     Vals.push_back(getEncodedDLLStorageClass(F));
1376     Vals.push_back(F.hasComdat() ? VE.getComdatID(F.getComdat()) : 0);
1377     Vals.push_back(F.hasPrefixData() ? (VE.getValueID(F.getPrefixData()) + 1)
1378                                      : 0);
1379     Vals.push_back(
1380         F.hasPersonalityFn() ? (VE.getValueID(F.getPersonalityFn()) + 1) : 0);
1381 
1382     unsigned AbbrevToUse = 0;
1383     Stream.EmitRecord(bitc::MODULE_CODE_FUNCTION, Vals, AbbrevToUse);
1384     Vals.clear();
1385   }
1386 
1387   // Emit the alias information.
1388   for (const GlobalAlias &A : M.aliases()) {
1389     // ALIAS: [alias type, aliasee val#, linkage, visibility]
1390     Vals.push_back(getTypeID(A.getValueType(), &A));
1391     Vals.push_back(VE.getValueID(A.getAliasee()));
1392     Vals.push_back(getEncodedLinkage(A));
1393     Vals.push_back(getEncodedVisibility(A));
1394     Vals.push_back(getEncodedDLLStorageClass(A));
1395     Vals.push_back(getEncodedThreadLocalMode(A));
1396     Vals.push_back(A.getUnnamedAddr() != GlobalValue::UnnamedAddr::None);
1397     unsigned AbbrevToUse = 0;
1398     Stream.EmitRecord(bitc::MODULE_CODE_ALIAS_OLD, Vals, AbbrevToUse);
1399     Vals.clear();
1400   }
1401 }
1402 
1403 void DXILBitcodeWriter::writeValueAsMetadata(
1404     const ValueAsMetadata *MD, SmallVectorImpl<uint64_t> &Record) {
1405   // Mimic an MDNode with a value as one operand.
1406   Value *V = MD->getValue();
1407   Type *Ty = V->getType();
1408   if (Function *F = dyn_cast<Function>(V))
1409     Ty = TypedPointerType::get(F->getFunctionType(), F->getAddressSpace());
1410   else if (GlobalVariable *GV = dyn_cast<GlobalVariable>(V))
1411     Ty = TypedPointerType::get(GV->getValueType(), GV->getAddressSpace());
1412   Record.push_back(getTypeID(Ty));
1413   Record.push_back(VE.getValueID(V));
1414   Stream.EmitRecord(bitc::METADATA_VALUE, Record, 0);
1415   Record.clear();
1416 }
1417 
1418 void DXILBitcodeWriter::writeMDTuple(const MDTuple *N,
1419                                      SmallVectorImpl<uint64_t> &Record,
1420                                      unsigned Abbrev) {
1421   for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i) {
1422     Metadata *MD = N->getOperand(i);
1423     assert(!(MD && isa<LocalAsMetadata>(MD)) &&
1424            "Unexpected function-local metadata");
1425     Record.push_back(VE.getMetadataOrNullID(MD));
1426   }
1427   Stream.EmitRecord(N->isDistinct() ? bitc::METADATA_DISTINCT_NODE
1428                                     : bitc::METADATA_NODE,
1429                     Record, Abbrev);
1430   Record.clear();
1431 }
1432 
1433 void DXILBitcodeWriter::writeDILocation(const DILocation *N,
1434                                         SmallVectorImpl<uint64_t> &Record,
1435                                         unsigned &Abbrev) {
1436   if (!Abbrev)
1437     Abbrev = createDILocationAbbrev();
1438   Record.push_back(N->isDistinct());
1439   Record.push_back(N->getLine());
1440   Record.push_back(N->getColumn());
1441   Record.push_back(VE.getMetadataID(N->getScope()));
1442   Record.push_back(VE.getMetadataOrNullID(N->getInlinedAt()));
1443 
1444   Stream.EmitRecord(bitc::METADATA_LOCATION, Record, Abbrev);
1445   Record.clear();
1446 }
1447 
1448 static uint64_t rotateSign(APInt Val) {
1449   int64_t I = Val.getSExtValue();
1450   uint64_t U = I;
1451   return I < 0 ? ~(U << 1) : U << 1;
1452 }
1453 
1454 static uint64_t rotateSign(DISubrange::BoundType Val) {
1455   return rotateSign(Val.get<ConstantInt *>()->getValue());
1456 }
1457 
1458 void DXILBitcodeWriter::writeDISubrange(const DISubrange *N,
1459                                         SmallVectorImpl<uint64_t> &Record,
1460                                         unsigned Abbrev) {
1461   Record.push_back(N->isDistinct());
1462   Record.push_back(
1463       N->getCount().get<ConstantInt *>()->getValue().getSExtValue());
1464   Record.push_back(rotateSign(N->getLowerBound()));
1465 
1466   Stream.EmitRecord(bitc::METADATA_SUBRANGE, Record, Abbrev);
1467   Record.clear();
1468 }
1469 
1470 void DXILBitcodeWriter::writeDIEnumerator(const DIEnumerator *N,
1471                                           SmallVectorImpl<uint64_t> &Record,
1472                                           unsigned Abbrev) {
1473   Record.push_back(N->isDistinct());
1474   Record.push_back(rotateSign(N->getValue()));
1475   Record.push_back(VE.getMetadataOrNullID(N->getRawName()));
1476 
1477   Stream.EmitRecord(bitc::METADATA_ENUMERATOR, Record, Abbrev);
1478   Record.clear();
1479 }
1480 
1481 void DXILBitcodeWriter::writeDIBasicType(const DIBasicType *N,
1482                                          SmallVectorImpl<uint64_t> &Record,
1483                                          unsigned Abbrev) {
1484   Record.push_back(N->isDistinct());
1485   Record.push_back(N->getTag());
1486   Record.push_back(VE.getMetadataOrNullID(N->getRawName()));
1487   Record.push_back(N->getSizeInBits());
1488   Record.push_back(N->getAlignInBits());
1489   Record.push_back(N->getEncoding());
1490 
1491   Stream.EmitRecord(bitc::METADATA_BASIC_TYPE, Record, Abbrev);
1492   Record.clear();
1493 }
1494 
1495 void DXILBitcodeWriter::writeDIDerivedType(const DIDerivedType *N,
1496                                            SmallVectorImpl<uint64_t> &Record,
1497                                            unsigned Abbrev) {
1498   Record.push_back(N->isDistinct());
1499   Record.push_back(N->getTag());
1500   Record.push_back(VE.getMetadataOrNullID(N->getRawName()));
1501   Record.push_back(VE.getMetadataOrNullID(N->getFile()));
1502   Record.push_back(N->getLine());
1503   Record.push_back(VE.getMetadataOrNullID(N->getScope()));
1504   Record.push_back(VE.getMetadataOrNullID(N->getBaseType()));
1505   Record.push_back(N->getSizeInBits());
1506   Record.push_back(N->getAlignInBits());
1507   Record.push_back(N->getOffsetInBits());
1508   Record.push_back(N->getFlags());
1509   Record.push_back(VE.getMetadataOrNullID(N->getExtraData()));
1510 
1511   Stream.EmitRecord(bitc::METADATA_DERIVED_TYPE, Record, Abbrev);
1512   Record.clear();
1513 }
1514 
1515 void DXILBitcodeWriter::writeDICompositeType(const DICompositeType *N,
1516                                              SmallVectorImpl<uint64_t> &Record,
1517                                              unsigned Abbrev) {
1518   Record.push_back(N->isDistinct());
1519   Record.push_back(N->getTag());
1520   Record.push_back(VE.getMetadataOrNullID(N->getRawName()));
1521   Record.push_back(VE.getMetadataOrNullID(N->getFile()));
1522   Record.push_back(N->getLine());
1523   Record.push_back(VE.getMetadataOrNullID(N->getScope()));
1524   Record.push_back(VE.getMetadataOrNullID(N->getBaseType()));
1525   Record.push_back(N->getSizeInBits());
1526   Record.push_back(N->getAlignInBits());
1527   Record.push_back(N->getOffsetInBits());
1528   Record.push_back(N->getFlags());
1529   Record.push_back(VE.getMetadataOrNullID(N->getElements().get()));
1530   Record.push_back(N->getRuntimeLang());
1531   Record.push_back(VE.getMetadataOrNullID(N->getVTableHolder()));
1532   Record.push_back(VE.getMetadataOrNullID(N->getTemplateParams().get()));
1533   Record.push_back(VE.getMetadataOrNullID(N->getRawIdentifier()));
1534 
1535   Stream.EmitRecord(bitc::METADATA_COMPOSITE_TYPE, Record, Abbrev);
1536   Record.clear();
1537 }
1538 
1539 void DXILBitcodeWriter::writeDISubroutineType(const DISubroutineType *N,
1540                                               SmallVectorImpl<uint64_t> &Record,
1541                                               unsigned Abbrev) {
1542   Record.push_back(N->isDistinct());
1543   Record.push_back(N->getFlags());
1544   Record.push_back(VE.getMetadataOrNullID(N->getTypeArray().get()));
1545 
1546   Stream.EmitRecord(bitc::METADATA_SUBROUTINE_TYPE, Record, Abbrev);
1547   Record.clear();
1548 }
1549 
1550 void DXILBitcodeWriter::writeDIFile(const DIFile *N,
1551                                     SmallVectorImpl<uint64_t> &Record,
1552                                     unsigned Abbrev) {
1553   Record.push_back(N->isDistinct());
1554   Record.push_back(VE.getMetadataOrNullID(N->getRawFilename()));
1555   Record.push_back(VE.getMetadataOrNullID(N->getRawDirectory()));
1556 
1557   Stream.EmitRecord(bitc::METADATA_FILE, Record, Abbrev);
1558   Record.clear();
1559 }
1560 
1561 void DXILBitcodeWriter::writeDICompileUnit(const DICompileUnit *N,
1562                                            SmallVectorImpl<uint64_t> &Record,
1563                                            unsigned Abbrev) {
1564   Record.push_back(N->isDistinct());
1565   Record.push_back(N->getSourceLanguage());
1566   Record.push_back(VE.getMetadataOrNullID(N->getFile()));
1567   Record.push_back(VE.getMetadataOrNullID(N->getRawProducer()));
1568   Record.push_back(N->isOptimized());
1569   Record.push_back(VE.getMetadataOrNullID(N->getRawFlags()));
1570   Record.push_back(N->getRuntimeVersion());
1571   Record.push_back(VE.getMetadataOrNullID(N->getRawSplitDebugFilename()));
1572   Record.push_back(N->getEmissionKind());
1573   Record.push_back(VE.getMetadataOrNullID(N->getEnumTypes().get()));
1574   Record.push_back(VE.getMetadataOrNullID(N->getRetainedTypes().get()));
1575   Record.push_back(/* subprograms */ 0);
1576   Record.push_back(VE.getMetadataOrNullID(N->getGlobalVariables().get()));
1577   Record.push_back(VE.getMetadataOrNullID(N->getImportedEntities().get()));
1578   Record.push_back(N->getDWOId());
1579 
1580   Stream.EmitRecord(bitc::METADATA_COMPILE_UNIT, Record, Abbrev);
1581   Record.clear();
1582 }
1583 
1584 void DXILBitcodeWriter::writeDISubprogram(const DISubprogram *N,
1585                                           SmallVectorImpl<uint64_t> &Record,
1586                                           unsigned Abbrev) {
1587   Record.push_back(N->isDistinct());
1588   Record.push_back(VE.getMetadataOrNullID(N->getScope()));
1589   Record.push_back(VE.getMetadataOrNullID(N->getRawName()));
1590   Record.push_back(VE.getMetadataOrNullID(N->getRawLinkageName()));
1591   Record.push_back(VE.getMetadataOrNullID(N->getFile()));
1592   Record.push_back(N->getLine());
1593   Record.push_back(VE.getMetadataOrNullID(N->getType()));
1594   Record.push_back(N->isLocalToUnit());
1595   Record.push_back(N->isDefinition());
1596   Record.push_back(N->getScopeLine());
1597   Record.push_back(VE.getMetadataOrNullID(N->getContainingType()));
1598   Record.push_back(N->getVirtuality());
1599   Record.push_back(N->getVirtualIndex());
1600   Record.push_back(N->getFlags());
1601   Record.push_back(N->isOptimized());
1602   Record.push_back(VE.getMetadataOrNullID(N->getRawUnit()));
1603   Record.push_back(VE.getMetadataOrNullID(N->getTemplateParams().get()));
1604   Record.push_back(VE.getMetadataOrNullID(N->getDeclaration()));
1605   Record.push_back(VE.getMetadataOrNullID(N->getRetainedNodes().get()));
1606 
1607   Stream.EmitRecord(bitc::METADATA_SUBPROGRAM, Record, Abbrev);
1608   Record.clear();
1609 }
1610 
1611 void DXILBitcodeWriter::writeDILexicalBlock(const DILexicalBlock *N,
1612                                             SmallVectorImpl<uint64_t> &Record,
1613                                             unsigned Abbrev) {
1614   Record.push_back(N->isDistinct());
1615   Record.push_back(VE.getMetadataOrNullID(N->getScope()));
1616   Record.push_back(VE.getMetadataOrNullID(N->getFile()));
1617   Record.push_back(N->getLine());
1618   Record.push_back(N->getColumn());
1619 
1620   Stream.EmitRecord(bitc::METADATA_LEXICAL_BLOCK, Record, Abbrev);
1621   Record.clear();
1622 }
1623 
1624 void DXILBitcodeWriter::writeDILexicalBlockFile(
1625     const DILexicalBlockFile *N, SmallVectorImpl<uint64_t> &Record,
1626     unsigned Abbrev) {
1627   Record.push_back(N->isDistinct());
1628   Record.push_back(VE.getMetadataOrNullID(N->getScope()));
1629   Record.push_back(VE.getMetadataOrNullID(N->getFile()));
1630   Record.push_back(N->getDiscriminator());
1631 
1632   Stream.EmitRecord(bitc::METADATA_LEXICAL_BLOCK_FILE, Record, Abbrev);
1633   Record.clear();
1634 }
1635 
1636 void DXILBitcodeWriter::writeDINamespace(const DINamespace *N,
1637                                          SmallVectorImpl<uint64_t> &Record,
1638                                          unsigned Abbrev) {
1639   Record.push_back(N->isDistinct());
1640   Record.push_back(VE.getMetadataOrNullID(N->getScope()));
1641   Record.push_back(VE.getMetadataOrNullID(N->getFile()));
1642   Record.push_back(VE.getMetadataOrNullID(N->getRawName()));
1643   Record.push_back(/* line number */ 0);
1644 
1645   Stream.EmitRecord(bitc::METADATA_NAMESPACE, Record, Abbrev);
1646   Record.clear();
1647 }
1648 
1649 void DXILBitcodeWriter::writeDIModule(const DIModule *N,
1650                                       SmallVectorImpl<uint64_t> &Record,
1651                                       unsigned Abbrev) {
1652   Record.push_back(N->isDistinct());
1653   for (auto &I : N->operands())
1654     Record.push_back(VE.getMetadataOrNullID(I));
1655 
1656   Stream.EmitRecord(bitc::METADATA_MODULE, Record, Abbrev);
1657   Record.clear();
1658 }
1659 
1660 void DXILBitcodeWriter::writeDITemplateTypeParameter(
1661     const DITemplateTypeParameter *N, SmallVectorImpl<uint64_t> &Record,
1662     unsigned Abbrev) {
1663   Record.push_back(N->isDistinct());
1664   Record.push_back(VE.getMetadataOrNullID(N->getRawName()));
1665   Record.push_back(VE.getMetadataOrNullID(N->getType()));
1666 
1667   Stream.EmitRecord(bitc::METADATA_TEMPLATE_TYPE, Record, Abbrev);
1668   Record.clear();
1669 }
1670 
1671 void DXILBitcodeWriter::writeDITemplateValueParameter(
1672     const DITemplateValueParameter *N, SmallVectorImpl<uint64_t> &Record,
1673     unsigned Abbrev) {
1674   Record.push_back(N->isDistinct());
1675   Record.push_back(N->getTag());
1676   Record.push_back(VE.getMetadataOrNullID(N->getRawName()));
1677   Record.push_back(VE.getMetadataOrNullID(N->getType()));
1678   Record.push_back(VE.getMetadataOrNullID(N->getValue()));
1679 
1680   Stream.EmitRecord(bitc::METADATA_TEMPLATE_VALUE, Record, Abbrev);
1681   Record.clear();
1682 }
1683 
1684 void DXILBitcodeWriter::writeDIGlobalVariable(const DIGlobalVariable *N,
1685                                               SmallVectorImpl<uint64_t> &Record,
1686                                               unsigned Abbrev) {
1687   Record.push_back(N->isDistinct());
1688   Record.push_back(VE.getMetadataOrNullID(N->getScope()));
1689   Record.push_back(VE.getMetadataOrNullID(N->getRawName()));
1690   Record.push_back(VE.getMetadataOrNullID(N->getRawLinkageName()));
1691   Record.push_back(VE.getMetadataOrNullID(N->getFile()));
1692   Record.push_back(N->getLine());
1693   Record.push_back(VE.getMetadataOrNullID(N->getType()));
1694   Record.push_back(N->isLocalToUnit());
1695   Record.push_back(N->isDefinition());
1696   Record.push_back(/* N->getRawVariable() */ 0);
1697   Record.push_back(VE.getMetadataOrNullID(N->getStaticDataMemberDeclaration()));
1698 
1699   Stream.EmitRecord(bitc::METADATA_GLOBAL_VAR, Record, Abbrev);
1700   Record.clear();
1701 }
1702 
1703 void DXILBitcodeWriter::writeDILocalVariable(const DILocalVariable *N,
1704                                              SmallVectorImpl<uint64_t> &Record,
1705                                              unsigned Abbrev) {
1706   Record.push_back(N->isDistinct());
1707   Record.push_back(N->getTag());
1708   Record.push_back(VE.getMetadataOrNullID(N->getScope()));
1709   Record.push_back(VE.getMetadataOrNullID(N->getRawName()));
1710   Record.push_back(VE.getMetadataOrNullID(N->getFile()));
1711   Record.push_back(N->getLine());
1712   Record.push_back(VE.getMetadataOrNullID(N->getType()));
1713   Record.push_back(N->getArg());
1714   Record.push_back(N->getFlags());
1715 
1716   Stream.EmitRecord(bitc::METADATA_LOCAL_VAR, Record, Abbrev);
1717   Record.clear();
1718 }
1719 
1720 void DXILBitcodeWriter::writeDIExpression(const DIExpression *N,
1721                                           SmallVectorImpl<uint64_t> &Record,
1722                                           unsigned Abbrev) {
1723   Record.reserve(N->getElements().size() + 1);
1724 
1725   Record.push_back(N->isDistinct());
1726   Record.append(N->elements_begin(), N->elements_end());
1727 
1728   Stream.EmitRecord(bitc::METADATA_EXPRESSION, Record, Abbrev);
1729   Record.clear();
1730 }
1731 
1732 void DXILBitcodeWriter::writeDIObjCProperty(const DIObjCProperty *N,
1733                                             SmallVectorImpl<uint64_t> &Record,
1734                                             unsigned Abbrev) {
1735   llvm_unreachable("DXIL does not support objc!!!");
1736 }
1737 
1738 void DXILBitcodeWriter::writeDIImportedEntity(const DIImportedEntity *N,
1739                                               SmallVectorImpl<uint64_t> &Record,
1740                                               unsigned Abbrev) {
1741   Record.push_back(N->isDistinct());
1742   Record.push_back(N->getTag());
1743   Record.push_back(VE.getMetadataOrNullID(N->getScope()));
1744   Record.push_back(VE.getMetadataOrNullID(N->getEntity()));
1745   Record.push_back(N->getLine());
1746   Record.push_back(VE.getMetadataOrNullID(N->getRawName()));
1747 
1748   Stream.EmitRecord(bitc::METADATA_IMPORTED_ENTITY, Record, Abbrev);
1749   Record.clear();
1750 }
1751 
1752 unsigned DXILBitcodeWriter::createDILocationAbbrev() {
1753   // Abbrev for METADATA_LOCATION.
1754   //
1755   // Assume the column is usually under 128, and always output the inlined-at
1756   // location (it's never more expensive than building an array size 1).
1757   std::shared_ptr<BitCodeAbbrev> Abbv = std::make_shared<BitCodeAbbrev>();
1758   Abbv->Add(BitCodeAbbrevOp(bitc::METADATA_LOCATION));
1759   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1));
1760   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
1761   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
1762   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
1763   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
1764   return Stream.EmitAbbrev(std::move(Abbv));
1765 }
1766 
1767 unsigned DXILBitcodeWriter::createGenericDINodeAbbrev() {
1768   // Abbrev for METADATA_GENERIC_DEBUG.
1769   //
1770   // Assume the column is usually under 128, and always output the inlined-at
1771   // location (it's never more expensive than building an array size 1).
1772   std::shared_ptr<BitCodeAbbrev> Abbv = std::make_shared<BitCodeAbbrev>();
1773   Abbv->Add(BitCodeAbbrevOp(bitc::METADATA_GENERIC_DEBUG));
1774   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1));
1775   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
1776   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1));
1777   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
1778   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1779   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
1780   return Stream.EmitAbbrev(std::move(Abbv));
1781 }
1782 
1783 void DXILBitcodeWriter::writeMetadataRecords(ArrayRef<const Metadata *> MDs,
1784                                              SmallVectorImpl<uint64_t> &Record,
1785                                              std::vector<unsigned> *MDAbbrevs,
1786                                              std::vector<uint64_t> *IndexPos) {
1787   if (MDs.empty())
1788     return;
1789 
1790     // Initialize MDNode abbreviations.
1791 #define HANDLE_MDNODE_LEAF(CLASS) unsigned CLASS##Abbrev = 0;
1792 #include "llvm/IR/Metadata.def"
1793 
1794   for (const Metadata *MD : MDs) {
1795     if (IndexPos)
1796       IndexPos->push_back(Stream.GetCurrentBitNo());
1797     if (const MDNode *N = dyn_cast<MDNode>(MD)) {
1798       assert(N->isResolved() && "Expected forward references to be resolved");
1799 
1800       switch (N->getMetadataID()) {
1801       default:
1802         llvm_unreachable("Invalid MDNode subclass");
1803 #define HANDLE_MDNODE_LEAF(CLASS)                                              \
1804   case Metadata::CLASS##Kind:                                                  \
1805     if (MDAbbrevs)                                                             \
1806       write##CLASS(cast<CLASS>(N), Record,                                     \
1807                    (*MDAbbrevs)[MetadataAbbrev::CLASS##AbbrevID]);             \
1808     else                                                                       \
1809       write##CLASS(cast<CLASS>(N), Record, CLASS##Abbrev);                     \
1810     continue;
1811 #include "llvm/IR/Metadata.def"
1812       }
1813     }
1814     writeValueAsMetadata(cast<ValueAsMetadata>(MD), Record);
1815   }
1816 }
1817 
1818 unsigned DXILBitcodeWriter::createMetadataStringsAbbrev() {
1819   auto Abbv = std::make_shared<BitCodeAbbrev>();
1820   Abbv->Add(BitCodeAbbrevOp(bitc::METADATA_STRING_OLD));
1821   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1822   Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 8));
1823   return Stream.EmitAbbrev(std::move(Abbv));
1824 }
1825 
1826 void DXILBitcodeWriter::writeMetadataStrings(
1827     ArrayRef<const Metadata *> Strings, SmallVectorImpl<uint64_t> &Record) {
1828   for (const Metadata *MD : Strings) {
1829     const MDString *MDS = cast<MDString>(MD);
1830     // Code: [strchar x N]
1831     Record.append(MDS->bytes_begin(), MDS->bytes_end());
1832 
1833     // Emit the finished record.
1834     Stream.EmitRecord(bitc::METADATA_STRING_OLD, Record,
1835                       createMetadataStringsAbbrev());
1836     Record.clear();
1837   }
1838 }
1839 
1840 void DXILBitcodeWriter::writeModuleMetadata() {
1841   if (!VE.hasMDs() && M.named_metadata_empty())
1842     return;
1843 
1844   Stream.EnterSubblock(bitc::METADATA_BLOCK_ID, 5);
1845 
1846   // Emit all abbrevs upfront, so that the reader can jump in the middle of the
1847   // block and load any metadata.
1848   std::vector<unsigned> MDAbbrevs;
1849 
1850   MDAbbrevs.resize(MetadataAbbrev::LastPlusOne);
1851   MDAbbrevs[MetadataAbbrev::DILocationAbbrevID] = createDILocationAbbrev();
1852   MDAbbrevs[MetadataAbbrev::GenericDINodeAbbrevID] =
1853       createGenericDINodeAbbrev();
1854 
1855   unsigned NameAbbrev = 0;
1856   if (!M.named_metadata_empty()) {
1857     // Abbrev for METADATA_NAME.
1858     std::shared_ptr<BitCodeAbbrev> Abbv = std::make_shared<BitCodeAbbrev>();
1859     Abbv->Add(BitCodeAbbrevOp(bitc::METADATA_NAME));
1860     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1861     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 8));
1862     NameAbbrev = Stream.EmitAbbrev(std::move(Abbv));
1863   }
1864 
1865   SmallVector<uint64_t, 64> Record;
1866   writeMetadataStrings(VE.getMDStrings(), Record);
1867 
1868   std::vector<uint64_t> IndexPos;
1869   IndexPos.reserve(VE.getNonMDStrings().size());
1870   writeMetadataRecords(VE.getNonMDStrings(), Record, &MDAbbrevs, &IndexPos);
1871 
1872   // Write named metadata.
1873   for (const NamedMDNode &NMD : M.named_metadata()) {
1874     // Write name.
1875     StringRef Str = NMD.getName();
1876     Record.append(Str.bytes_begin(), Str.bytes_end());
1877     Stream.EmitRecord(bitc::METADATA_NAME, Record, NameAbbrev);
1878     Record.clear();
1879 
1880     // Write named metadata operands.
1881     for (const MDNode *N : NMD.operands())
1882       Record.push_back(VE.getMetadataID(N));
1883     Stream.EmitRecord(bitc::METADATA_NAMED_NODE, Record, 0);
1884     Record.clear();
1885   }
1886 
1887   Stream.ExitBlock();
1888 }
1889 
1890 void DXILBitcodeWriter::writeFunctionMetadata(const Function &F) {
1891   if (!VE.hasMDs())
1892     return;
1893 
1894   Stream.EnterSubblock(bitc::METADATA_BLOCK_ID, 4);
1895   SmallVector<uint64_t, 64> Record;
1896   writeMetadataStrings(VE.getMDStrings(), Record);
1897   writeMetadataRecords(VE.getNonMDStrings(), Record);
1898   Stream.ExitBlock();
1899 }
1900 
1901 void DXILBitcodeWriter::writeFunctionMetadataAttachment(const Function &F) {
1902   Stream.EnterSubblock(bitc::METADATA_ATTACHMENT_ID, 3);
1903 
1904   SmallVector<uint64_t, 64> Record;
1905 
1906   // Write metadata attachments
1907   // METADATA_ATTACHMENT - [m x [value, [n x [id, mdnode]]]
1908   SmallVector<std::pair<unsigned, MDNode *>, 4> MDs;
1909   F.getAllMetadata(MDs);
1910   if (!MDs.empty()) {
1911     for (const auto &I : MDs) {
1912       Record.push_back(I.first);
1913       Record.push_back(VE.getMetadataID(I.second));
1914     }
1915     Stream.EmitRecord(bitc::METADATA_ATTACHMENT, Record, 0);
1916     Record.clear();
1917   }
1918 
1919   for (const BasicBlock &BB : F)
1920     for (const Instruction &I : BB) {
1921       MDs.clear();
1922       I.getAllMetadataOtherThanDebugLoc(MDs);
1923 
1924       // If no metadata, ignore instruction.
1925       if (MDs.empty())
1926         continue;
1927 
1928       Record.push_back(VE.getInstructionID(&I));
1929 
1930       for (unsigned i = 0, e = MDs.size(); i != e; ++i) {
1931         Record.push_back(MDs[i].first);
1932         Record.push_back(VE.getMetadataID(MDs[i].second));
1933       }
1934       Stream.EmitRecord(bitc::METADATA_ATTACHMENT, Record, 0);
1935       Record.clear();
1936     }
1937 
1938   Stream.ExitBlock();
1939 }
1940 
1941 void DXILBitcodeWriter::writeModuleMetadataKinds() {
1942   SmallVector<uint64_t, 64> Record;
1943 
1944   // Write metadata kinds
1945   // METADATA_KIND - [n x [id, name]]
1946   SmallVector<StringRef, 8> Names;
1947   M.getMDKindNames(Names);
1948 
1949   if (Names.empty())
1950     return;
1951 
1952   Stream.EnterSubblock(bitc::METADATA_BLOCK_ID, 3);
1953 
1954   for (unsigned MDKindID = 0, e = Names.size(); MDKindID != e; ++MDKindID) {
1955     Record.push_back(MDKindID);
1956     StringRef KName = Names[MDKindID];
1957     Record.append(KName.begin(), KName.end());
1958 
1959     Stream.EmitRecord(bitc::METADATA_KIND, Record, 0);
1960     Record.clear();
1961   }
1962 
1963   Stream.ExitBlock();
1964 }
1965 
1966 void DXILBitcodeWriter::writeConstants(unsigned FirstVal, unsigned LastVal,
1967                                        bool isGlobal) {
1968   if (FirstVal == LastVal)
1969     return;
1970 
1971   Stream.EnterSubblock(bitc::CONSTANTS_BLOCK_ID, 4);
1972 
1973   unsigned AggregateAbbrev = 0;
1974   unsigned String8Abbrev = 0;
1975   unsigned CString7Abbrev = 0;
1976   unsigned CString6Abbrev = 0;
1977   // If this is a constant pool for the module, emit module-specific abbrevs.
1978   if (isGlobal) {
1979     // Abbrev for CST_CODE_AGGREGATE.
1980     auto Abbv = std::make_shared<BitCodeAbbrev>();
1981     Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_AGGREGATE));
1982     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1983     Abbv->Add(
1984         BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, Log2_32_Ceil(LastVal + 1)));
1985     AggregateAbbrev = Stream.EmitAbbrev(std::move(Abbv));
1986 
1987     // Abbrev for CST_CODE_STRING.
1988     Abbv = std::make_shared<BitCodeAbbrev>();
1989     Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_STRING));
1990     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1991     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 8));
1992     String8Abbrev = Stream.EmitAbbrev(std::move(Abbv));
1993     // Abbrev for CST_CODE_CSTRING.
1994     Abbv = std::make_shared<BitCodeAbbrev>();
1995     Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_CSTRING));
1996     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
1997     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 7));
1998     CString7Abbrev = Stream.EmitAbbrev(std::move(Abbv));
1999     // Abbrev for CST_CODE_CSTRING.
2000     Abbv = std::make_shared<BitCodeAbbrev>();
2001     Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_CSTRING));
2002     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
2003     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Char6));
2004     CString6Abbrev = Stream.EmitAbbrev(std::move(Abbv));
2005   }
2006 
2007   SmallVector<uint64_t, 64> Record;
2008 
2009   const ValueEnumerator::ValueList &Vals = VE.getValues();
2010   Type *LastTy = nullptr;
2011   for (unsigned i = FirstVal; i != LastVal; ++i) {
2012     const Value *V = Vals[i].first;
2013     // If we need to switch types, do so now.
2014     if (V->getType() != LastTy) {
2015       LastTy = V->getType();
2016       Record.push_back(getTypeID(LastTy, V));
2017       Stream.EmitRecord(bitc::CST_CODE_SETTYPE, Record,
2018                         CONSTANTS_SETTYPE_ABBREV);
2019       Record.clear();
2020     }
2021 
2022     if (const InlineAsm *IA = dyn_cast<InlineAsm>(V)) {
2023       Record.push_back(unsigned(IA->hasSideEffects()) |
2024                        unsigned(IA->isAlignStack()) << 1 |
2025                        unsigned(IA->getDialect() & 1) << 2);
2026 
2027       // Add the asm string.
2028       const std::string &AsmStr = IA->getAsmString();
2029       Record.push_back(AsmStr.size());
2030       Record.append(AsmStr.begin(), AsmStr.end());
2031 
2032       // Add the constraint string.
2033       const std::string &ConstraintStr = IA->getConstraintString();
2034       Record.push_back(ConstraintStr.size());
2035       Record.append(ConstraintStr.begin(), ConstraintStr.end());
2036       Stream.EmitRecord(bitc::CST_CODE_INLINEASM, Record);
2037       Record.clear();
2038       continue;
2039     }
2040     const Constant *C = cast<Constant>(V);
2041     unsigned Code = -1U;
2042     unsigned AbbrevToUse = 0;
2043     if (C->isNullValue()) {
2044       Code = bitc::CST_CODE_NULL;
2045     } else if (isa<UndefValue>(C)) {
2046       Code = bitc::CST_CODE_UNDEF;
2047     } else if (const ConstantInt *IV = dyn_cast<ConstantInt>(C)) {
2048       if (IV->getBitWidth() <= 64) {
2049         uint64_t V = IV->getSExtValue();
2050         emitSignedInt64(Record, V);
2051         Code = bitc::CST_CODE_INTEGER;
2052         AbbrevToUse = CONSTANTS_INTEGER_ABBREV;
2053       } else { // Wide integers, > 64 bits in size.
2054         // We have an arbitrary precision integer value to write whose
2055         // bit width is > 64. However, in canonical unsigned integer
2056         // format it is likely that the high bits are going to be zero.
2057         // So, we only write the number of active words.
2058         unsigned NWords = IV->getValue().getActiveWords();
2059         const uint64_t *RawWords = IV->getValue().getRawData();
2060         for (unsigned i = 0; i != NWords; ++i) {
2061           emitSignedInt64(Record, RawWords[i]);
2062         }
2063         Code = bitc::CST_CODE_WIDE_INTEGER;
2064       }
2065     } else if (const ConstantFP *CFP = dyn_cast<ConstantFP>(C)) {
2066       Code = bitc::CST_CODE_FLOAT;
2067       Type *Ty = CFP->getType();
2068       if (Ty->isHalfTy() || Ty->isFloatTy() || Ty->isDoubleTy()) {
2069         Record.push_back(CFP->getValueAPF().bitcastToAPInt().getZExtValue());
2070       } else if (Ty->isX86_FP80Ty()) {
2071         // api needed to prevent premature destruction
2072         // bits are not in the same order as a normal i80 APInt, compensate.
2073         APInt api = CFP->getValueAPF().bitcastToAPInt();
2074         const uint64_t *p = api.getRawData();
2075         Record.push_back((p[1] << 48) | (p[0] >> 16));
2076         Record.push_back(p[0] & 0xffffLL);
2077       } else if (Ty->isFP128Ty() || Ty->isPPC_FP128Ty()) {
2078         APInt api = CFP->getValueAPF().bitcastToAPInt();
2079         const uint64_t *p = api.getRawData();
2080         Record.push_back(p[0]);
2081         Record.push_back(p[1]);
2082       } else {
2083         assert(0 && "Unknown FP type!");
2084       }
2085     } else if (isa<ConstantDataSequential>(C) &&
2086                cast<ConstantDataSequential>(C)->isString()) {
2087       const ConstantDataSequential *Str = cast<ConstantDataSequential>(C);
2088       // Emit constant strings specially.
2089       unsigned NumElts = Str->getNumElements();
2090       // If this is a null-terminated string, use the denser CSTRING encoding.
2091       if (Str->isCString()) {
2092         Code = bitc::CST_CODE_CSTRING;
2093         --NumElts; // Don't encode the null, which isn't allowed by char6.
2094       } else {
2095         Code = bitc::CST_CODE_STRING;
2096         AbbrevToUse = String8Abbrev;
2097       }
2098       bool isCStr7 = Code == bitc::CST_CODE_CSTRING;
2099       bool isCStrChar6 = Code == bitc::CST_CODE_CSTRING;
2100       for (unsigned i = 0; i != NumElts; ++i) {
2101         unsigned char V = Str->getElementAsInteger(i);
2102         Record.push_back(V);
2103         isCStr7 &= (V & 128) == 0;
2104         if (isCStrChar6)
2105           isCStrChar6 = BitCodeAbbrevOp::isChar6(V);
2106       }
2107 
2108       if (isCStrChar6)
2109         AbbrevToUse = CString6Abbrev;
2110       else if (isCStr7)
2111         AbbrevToUse = CString7Abbrev;
2112     } else if (const ConstantDataSequential *CDS =
2113                    dyn_cast<ConstantDataSequential>(C)) {
2114       Code = bitc::CST_CODE_DATA;
2115       Type *EltTy = CDS->getElementType();
2116       if (isa<IntegerType>(EltTy)) {
2117         for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i)
2118           Record.push_back(CDS->getElementAsInteger(i));
2119       } else if (EltTy->isFloatTy()) {
2120         for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
2121           union {
2122             float F;
2123             uint32_t I;
2124           };
2125           F = CDS->getElementAsFloat(i);
2126           Record.push_back(I);
2127         }
2128       } else {
2129         assert(EltTy->isDoubleTy() && "Unknown ConstantData element type");
2130         for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
2131           union {
2132             double F;
2133             uint64_t I;
2134           };
2135           F = CDS->getElementAsDouble(i);
2136           Record.push_back(I);
2137         }
2138       }
2139     } else if (isa<ConstantArray>(C) || isa<ConstantStruct>(C) ||
2140                isa<ConstantVector>(C)) {
2141       Code = bitc::CST_CODE_AGGREGATE;
2142       for (const Value *Op : C->operands())
2143         Record.push_back(VE.getValueID(Op));
2144       AbbrevToUse = AggregateAbbrev;
2145     } else if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(C)) {
2146       switch (CE->getOpcode()) {
2147       default:
2148         if (Instruction::isCast(CE->getOpcode())) {
2149           Code = bitc::CST_CODE_CE_CAST;
2150           Record.push_back(getEncodedCastOpcode(CE->getOpcode()));
2151           Record.push_back(
2152               getTypeID(C->getOperand(0)->getType(), C->getOperand(0)));
2153           Record.push_back(VE.getValueID(C->getOperand(0)));
2154           AbbrevToUse = CONSTANTS_CE_CAST_Abbrev;
2155         } else {
2156           assert(CE->getNumOperands() == 2 && "Unknown constant expr!");
2157           Code = bitc::CST_CODE_CE_BINOP;
2158           Record.push_back(getEncodedBinaryOpcode(CE->getOpcode()));
2159           Record.push_back(VE.getValueID(C->getOperand(0)));
2160           Record.push_back(VE.getValueID(C->getOperand(1)));
2161           uint64_t Flags = getOptimizationFlags(CE);
2162           if (Flags != 0)
2163             Record.push_back(Flags);
2164         }
2165         break;
2166       case Instruction::GetElementPtr: {
2167         Code = bitc::CST_CODE_CE_GEP;
2168         const auto *GO = cast<GEPOperator>(C);
2169         if (GO->isInBounds())
2170           Code = bitc::CST_CODE_CE_INBOUNDS_GEP;
2171         Record.push_back(getTypeID(GO->getSourceElementType()));
2172         for (unsigned i = 0, e = CE->getNumOperands(); i != e; ++i) {
2173           Record.push_back(
2174               getTypeID(C->getOperand(i)->getType(), C->getOperand(i)));
2175           Record.push_back(VE.getValueID(C->getOperand(i)));
2176         }
2177         break;
2178       }
2179       case Instruction::Select:
2180         Code = bitc::CST_CODE_CE_SELECT;
2181         Record.push_back(VE.getValueID(C->getOperand(0)));
2182         Record.push_back(VE.getValueID(C->getOperand(1)));
2183         Record.push_back(VE.getValueID(C->getOperand(2)));
2184         break;
2185       case Instruction::ExtractElement:
2186         Code = bitc::CST_CODE_CE_EXTRACTELT;
2187         Record.push_back(getTypeID(C->getOperand(0)->getType()));
2188         Record.push_back(VE.getValueID(C->getOperand(0)));
2189         Record.push_back(getTypeID(C->getOperand(1)->getType()));
2190         Record.push_back(VE.getValueID(C->getOperand(1)));
2191         break;
2192       case Instruction::InsertElement:
2193         Code = bitc::CST_CODE_CE_INSERTELT;
2194         Record.push_back(VE.getValueID(C->getOperand(0)));
2195         Record.push_back(VE.getValueID(C->getOperand(1)));
2196         Record.push_back(getTypeID(C->getOperand(2)->getType()));
2197         Record.push_back(VE.getValueID(C->getOperand(2)));
2198         break;
2199       case Instruction::ShuffleVector:
2200         // If the return type and argument types are the same, this is a
2201         // standard shufflevector instruction.  If the types are different,
2202         // then the shuffle is widening or truncating the input vectors, and
2203         // the argument type must also be encoded.
2204         if (C->getType() == C->getOperand(0)->getType()) {
2205           Code = bitc::CST_CODE_CE_SHUFFLEVEC;
2206         } else {
2207           Code = bitc::CST_CODE_CE_SHUFVEC_EX;
2208           Record.push_back(getTypeID(C->getOperand(0)->getType()));
2209         }
2210         Record.push_back(VE.getValueID(C->getOperand(0)));
2211         Record.push_back(VE.getValueID(C->getOperand(1)));
2212         Record.push_back(VE.getValueID(C->getOperand(2)));
2213         break;
2214       case Instruction::ICmp:
2215       case Instruction::FCmp:
2216         Code = bitc::CST_CODE_CE_CMP;
2217         Record.push_back(getTypeID(C->getOperand(0)->getType()));
2218         Record.push_back(VE.getValueID(C->getOperand(0)));
2219         Record.push_back(VE.getValueID(C->getOperand(1)));
2220         Record.push_back(CE->getPredicate());
2221         break;
2222       }
2223     } else if (const BlockAddress *BA = dyn_cast<BlockAddress>(C)) {
2224       Code = bitc::CST_CODE_BLOCKADDRESS;
2225       Record.push_back(getTypeID(BA->getFunction()->getType()));
2226       Record.push_back(VE.getValueID(BA->getFunction()));
2227       Record.push_back(VE.getGlobalBasicBlockID(BA->getBasicBlock()));
2228     } else {
2229 #ifndef NDEBUG
2230       C->dump();
2231 #endif
2232       llvm_unreachable("Unknown constant!");
2233     }
2234     Stream.EmitRecord(Code, Record, AbbrevToUse);
2235     Record.clear();
2236   }
2237 
2238   Stream.ExitBlock();
2239 }
2240 
2241 void DXILBitcodeWriter::writeModuleConstants() {
2242   const ValueEnumerator::ValueList &Vals = VE.getValues();
2243 
2244   // Find the first constant to emit, which is the first non-globalvalue value.
2245   // We know globalvalues have been emitted by WriteModuleInfo.
2246   for (unsigned i = 0, e = Vals.size(); i != e; ++i) {
2247     if (!isa<GlobalValue>(Vals[i].first)) {
2248       writeConstants(i, Vals.size(), true);
2249       return;
2250     }
2251   }
2252 }
2253 
2254 /// pushValueAndType - The file has to encode both the value and type id for
2255 /// many values, because we need to know what type to create for forward
2256 /// references.  However, most operands are not forward references, so this type
2257 /// field is not needed.
2258 ///
2259 /// This function adds V's value ID to Vals.  If the value ID is higher than the
2260 /// instruction ID, then it is a forward reference, and it also includes the
2261 /// type ID.  The value ID that is written is encoded relative to the InstID.
2262 bool DXILBitcodeWriter::pushValueAndType(const Value *V, unsigned InstID,
2263                                          SmallVectorImpl<unsigned> &Vals) {
2264   unsigned ValID = VE.getValueID(V);
2265   // Make encoding relative to the InstID.
2266   Vals.push_back(InstID - ValID);
2267   if (ValID >= InstID) {
2268     Vals.push_back(getTypeID(V->getType(), V));
2269     return true;
2270   }
2271   return false;
2272 }
2273 
2274 /// pushValue - Like pushValueAndType, but where the type of the value is
2275 /// omitted (perhaps it was already encoded in an earlier operand).
2276 void DXILBitcodeWriter::pushValue(const Value *V, unsigned InstID,
2277                                   SmallVectorImpl<unsigned> &Vals) {
2278   unsigned ValID = VE.getValueID(V);
2279   Vals.push_back(InstID - ValID);
2280 }
2281 
2282 void DXILBitcodeWriter::pushValueSigned(const Value *V, unsigned InstID,
2283                                         SmallVectorImpl<uint64_t> &Vals) {
2284   unsigned ValID = VE.getValueID(V);
2285   int64_t diff = ((int32_t)InstID - (int32_t)ValID);
2286   emitSignedInt64(Vals, diff);
2287 }
2288 
2289 /// WriteInstruction - Emit an instruction
2290 void DXILBitcodeWriter::writeInstruction(const Instruction &I, unsigned InstID,
2291                                          SmallVectorImpl<unsigned> &Vals) {
2292   unsigned Code = 0;
2293   unsigned AbbrevToUse = 0;
2294   VE.setInstructionID(&I);
2295   switch (I.getOpcode()) {
2296   default:
2297     if (Instruction::isCast(I.getOpcode())) {
2298       Code = bitc::FUNC_CODE_INST_CAST;
2299       if (!pushValueAndType(I.getOperand(0), InstID, Vals))
2300         AbbrevToUse = (unsigned)FUNCTION_INST_CAST_ABBREV;
2301       Vals.push_back(getTypeID(I.getType(), &I));
2302       Vals.push_back(getEncodedCastOpcode(I.getOpcode()));
2303     } else {
2304       assert(isa<BinaryOperator>(I) && "Unknown instruction!");
2305       Code = bitc::FUNC_CODE_INST_BINOP;
2306       if (!pushValueAndType(I.getOperand(0), InstID, Vals))
2307         AbbrevToUse = (unsigned)FUNCTION_INST_BINOP_ABBREV;
2308       pushValue(I.getOperand(1), InstID, Vals);
2309       Vals.push_back(getEncodedBinaryOpcode(I.getOpcode()));
2310       uint64_t Flags = getOptimizationFlags(&I);
2311       if (Flags != 0) {
2312         if (AbbrevToUse == (unsigned)FUNCTION_INST_BINOP_ABBREV)
2313           AbbrevToUse = (unsigned)FUNCTION_INST_BINOP_FLAGS_ABBREV;
2314         Vals.push_back(Flags);
2315       }
2316     }
2317     break;
2318 
2319   case Instruction::GetElementPtr: {
2320     Code = bitc::FUNC_CODE_INST_GEP;
2321     AbbrevToUse = (unsigned)FUNCTION_INST_GEP_ABBREV;
2322     auto &GEPInst = cast<GetElementPtrInst>(I);
2323     Vals.push_back(GEPInst.isInBounds());
2324     Vals.push_back(getTypeID(GEPInst.getSourceElementType()));
2325     for (unsigned i = 0, e = I.getNumOperands(); i != e; ++i)
2326       pushValueAndType(I.getOperand(i), InstID, Vals);
2327     break;
2328   }
2329   case Instruction::ExtractValue: {
2330     Code = bitc::FUNC_CODE_INST_EXTRACTVAL;
2331     pushValueAndType(I.getOperand(0), InstID, Vals);
2332     const ExtractValueInst *EVI = cast<ExtractValueInst>(&I);
2333     Vals.append(EVI->idx_begin(), EVI->idx_end());
2334     break;
2335   }
2336   case Instruction::InsertValue: {
2337     Code = bitc::FUNC_CODE_INST_INSERTVAL;
2338     pushValueAndType(I.getOperand(0), InstID, Vals);
2339     pushValueAndType(I.getOperand(1), InstID, Vals);
2340     const InsertValueInst *IVI = cast<InsertValueInst>(&I);
2341     Vals.append(IVI->idx_begin(), IVI->idx_end());
2342     break;
2343   }
2344   case Instruction::Select:
2345     Code = bitc::FUNC_CODE_INST_VSELECT;
2346     pushValueAndType(I.getOperand(1), InstID, Vals);
2347     pushValue(I.getOperand(2), InstID, Vals);
2348     pushValueAndType(I.getOperand(0), InstID, Vals);
2349     break;
2350   case Instruction::ExtractElement:
2351     Code = bitc::FUNC_CODE_INST_EXTRACTELT;
2352     pushValueAndType(I.getOperand(0), InstID, Vals);
2353     pushValueAndType(I.getOperand(1), InstID, Vals);
2354     break;
2355   case Instruction::InsertElement:
2356     Code = bitc::FUNC_CODE_INST_INSERTELT;
2357     pushValueAndType(I.getOperand(0), InstID, Vals);
2358     pushValue(I.getOperand(1), InstID, Vals);
2359     pushValueAndType(I.getOperand(2), InstID, Vals);
2360     break;
2361   case Instruction::ShuffleVector:
2362     Code = bitc::FUNC_CODE_INST_SHUFFLEVEC;
2363     pushValueAndType(I.getOperand(0), InstID, Vals);
2364     pushValue(I.getOperand(1), InstID, Vals);
2365     pushValue(cast<ShuffleVectorInst>(&I)->getShuffleMaskForBitcode(), InstID,
2366               Vals);
2367     break;
2368   case Instruction::ICmp:
2369   case Instruction::FCmp: {
2370     // compare returning Int1Ty or vector of Int1Ty
2371     Code = bitc::FUNC_CODE_INST_CMP2;
2372     pushValueAndType(I.getOperand(0), InstID, Vals);
2373     pushValue(I.getOperand(1), InstID, Vals);
2374     Vals.push_back(cast<CmpInst>(I).getPredicate());
2375     uint64_t Flags = getOptimizationFlags(&I);
2376     if (Flags != 0)
2377       Vals.push_back(Flags);
2378     break;
2379   }
2380 
2381   case Instruction::Ret: {
2382     Code = bitc::FUNC_CODE_INST_RET;
2383     unsigned NumOperands = I.getNumOperands();
2384     if (NumOperands == 0)
2385       AbbrevToUse = (unsigned)FUNCTION_INST_RET_VOID_ABBREV;
2386     else if (NumOperands == 1) {
2387       if (!pushValueAndType(I.getOperand(0), InstID, Vals))
2388         AbbrevToUse = (unsigned)FUNCTION_INST_RET_VAL_ABBREV;
2389     } else {
2390       for (unsigned i = 0, e = NumOperands; i != e; ++i)
2391         pushValueAndType(I.getOperand(i), InstID, Vals);
2392     }
2393   } break;
2394   case Instruction::Br: {
2395     Code = bitc::FUNC_CODE_INST_BR;
2396     const BranchInst &II = cast<BranchInst>(I);
2397     Vals.push_back(VE.getValueID(II.getSuccessor(0)));
2398     if (II.isConditional()) {
2399       Vals.push_back(VE.getValueID(II.getSuccessor(1)));
2400       pushValue(II.getCondition(), InstID, Vals);
2401     }
2402   } break;
2403   case Instruction::Switch: {
2404     Code = bitc::FUNC_CODE_INST_SWITCH;
2405     const SwitchInst &SI = cast<SwitchInst>(I);
2406     Vals.push_back(getTypeID(SI.getCondition()->getType()));
2407     pushValue(SI.getCondition(), InstID, Vals);
2408     Vals.push_back(VE.getValueID(SI.getDefaultDest()));
2409     for (auto Case : SI.cases()) {
2410       Vals.push_back(VE.getValueID(Case.getCaseValue()));
2411       Vals.push_back(VE.getValueID(Case.getCaseSuccessor()));
2412     }
2413   } break;
2414   case Instruction::IndirectBr:
2415     Code = bitc::FUNC_CODE_INST_INDIRECTBR;
2416     Vals.push_back(getTypeID(I.getOperand(0)->getType()));
2417     // Encode the address operand as relative, but not the basic blocks.
2418     pushValue(I.getOperand(0), InstID, Vals);
2419     for (unsigned i = 1, e = I.getNumOperands(); i != e; ++i)
2420       Vals.push_back(VE.getValueID(I.getOperand(i)));
2421     break;
2422 
2423   case Instruction::Invoke: {
2424     const InvokeInst *II = cast<InvokeInst>(&I);
2425     const Value *Callee = II->getCalledOperand();
2426     FunctionType *FTy = II->getFunctionType();
2427     Code = bitc::FUNC_CODE_INST_INVOKE;
2428 
2429     Vals.push_back(VE.getAttributeListID(II->getAttributes()));
2430     Vals.push_back(II->getCallingConv() | 1 << 13);
2431     Vals.push_back(VE.getValueID(II->getNormalDest()));
2432     Vals.push_back(VE.getValueID(II->getUnwindDest()));
2433     Vals.push_back(getTypeID(FTy));
2434     pushValueAndType(Callee, InstID, Vals);
2435 
2436     // Emit value #'s for the fixed parameters.
2437     for (unsigned i = 0, e = FTy->getNumParams(); i != e; ++i)
2438       pushValue(I.getOperand(i), InstID, Vals); // fixed param.
2439 
2440     // Emit type/value pairs for varargs params.
2441     if (FTy->isVarArg()) {
2442       for (unsigned i = FTy->getNumParams(), e = I.getNumOperands() - 3; i != e;
2443            ++i)
2444         pushValueAndType(I.getOperand(i), InstID, Vals); // vararg
2445     }
2446     break;
2447   }
2448   case Instruction::Resume:
2449     Code = bitc::FUNC_CODE_INST_RESUME;
2450     pushValueAndType(I.getOperand(0), InstID, Vals);
2451     break;
2452   case Instruction::Unreachable:
2453     Code = bitc::FUNC_CODE_INST_UNREACHABLE;
2454     AbbrevToUse = (unsigned)FUNCTION_INST_UNREACHABLE_ABBREV;
2455     break;
2456 
2457   case Instruction::PHI: {
2458     const PHINode &PN = cast<PHINode>(I);
2459     Code = bitc::FUNC_CODE_INST_PHI;
2460     // With the newer instruction encoding, forward references could give
2461     // negative valued IDs.  This is most common for PHIs, so we use
2462     // signed VBRs.
2463     SmallVector<uint64_t, 128> Vals64;
2464     Vals64.push_back(getTypeID(PN.getType()));
2465     for (unsigned i = 0, e = PN.getNumIncomingValues(); i != e; ++i) {
2466       pushValueSigned(PN.getIncomingValue(i), InstID, Vals64);
2467       Vals64.push_back(VE.getValueID(PN.getIncomingBlock(i)));
2468     }
2469     // Emit a Vals64 vector and exit.
2470     Stream.EmitRecord(Code, Vals64, AbbrevToUse);
2471     Vals64.clear();
2472     return;
2473   }
2474 
2475   case Instruction::LandingPad: {
2476     const LandingPadInst &LP = cast<LandingPadInst>(I);
2477     Code = bitc::FUNC_CODE_INST_LANDINGPAD;
2478     Vals.push_back(getTypeID(LP.getType()));
2479     Vals.push_back(LP.isCleanup());
2480     Vals.push_back(LP.getNumClauses());
2481     for (unsigned I = 0, E = LP.getNumClauses(); I != E; ++I) {
2482       if (LP.isCatch(I))
2483         Vals.push_back(LandingPadInst::Catch);
2484       else
2485         Vals.push_back(LandingPadInst::Filter);
2486       pushValueAndType(LP.getClause(I), InstID, Vals);
2487     }
2488     break;
2489   }
2490 
2491   case Instruction::Alloca: {
2492     Code = bitc::FUNC_CODE_INST_ALLOCA;
2493     const AllocaInst &AI = cast<AllocaInst>(I);
2494     Vals.push_back(getTypeID(AI.getAllocatedType()));
2495     Vals.push_back(getTypeID(I.getOperand(0)->getType()));
2496     Vals.push_back(VE.getValueID(I.getOperand(0))); // size.
2497     unsigned AlignRecord = Log2_32(AI.getAlign().value()) + 1;
2498     assert(AlignRecord < 1 << 5 && "alignment greater than 1 << 64");
2499     AlignRecord |= AI.isUsedWithInAlloca() << 5;
2500     AlignRecord |= 1 << 6;
2501     Vals.push_back(AlignRecord);
2502     break;
2503   }
2504 
2505   case Instruction::Load:
2506     if (cast<LoadInst>(I).isAtomic()) {
2507       Code = bitc::FUNC_CODE_INST_LOADATOMIC;
2508       pushValueAndType(I.getOperand(0), InstID, Vals);
2509     } else {
2510       Code = bitc::FUNC_CODE_INST_LOAD;
2511       if (!pushValueAndType(I.getOperand(0), InstID, Vals)) // ptr
2512         AbbrevToUse = (unsigned)FUNCTION_INST_LOAD_ABBREV;
2513     }
2514     Vals.push_back(getTypeID(I.getType()));
2515     Vals.push_back(Log2(cast<LoadInst>(I).getAlign()) + 1);
2516     Vals.push_back(cast<LoadInst>(I).isVolatile());
2517     if (cast<LoadInst>(I).isAtomic()) {
2518       Vals.push_back(getEncodedOrdering(cast<LoadInst>(I).getOrdering()));
2519       Vals.push_back(getEncodedSyncScopeID(cast<LoadInst>(I).getSyncScopeID()));
2520     }
2521     break;
2522   case Instruction::Store:
2523     if (cast<StoreInst>(I).isAtomic())
2524       Code = bitc::FUNC_CODE_INST_STOREATOMIC;
2525     else
2526       Code = bitc::FUNC_CODE_INST_STORE;
2527     pushValueAndType(I.getOperand(1), InstID, Vals); // ptrty + ptr
2528     pushValueAndType(I.getOperand(0), InstID, Vals); // valty + val
2529     Vals.push_back(Log2(cast<StoreInst>(I).getAlign()) + 1);
2530     Vals.push_back(cast<StoreInst>(I).isVolatile());
2531     if (cast<StoreInst>(I).isAtomic()) {
2532       Vals.push_back(getEncodedOrdering(cast<StoreInst>(I).getOrdering()));
2533       Vals.push_back(
2534           getEncodedSyncScopeID(cast<StoreInst>(I).getSyncScopeID()));
2535     }
2536     break;
2537   case Instruction::AtomicCmpXchg:
2538     Code = bitc::FUNC_CODE_INST_CMPXCHG;
2539     pushValueAndType(I.getOperand(0), InstID, Vals); // ptrty + ptr
2540     pushValueAndType(I.getOperand(1), InstID, Vals); // cmp.
2541     pushValue(I.getOperand(2), InstID, Vals);        // newval.
2542     Vals.push_back(cast<AtomicCmpXchgInst>(I).isVolatile());
2543     Vals.push_back(
2544         getEncodedOrdering(cast<AtomicCmpXchgInst>(I).getSuccessOrdering()));
2545     Vals.push_back(
2546         getEncodedSyncScopeID(cast<AtomicCmpXchgInst>(I).getSyncScopeID()));
2547     Vals.push_back(
2548         getEncodedOrdering(cast<AtomicCmpXchgInst>(I).getFailureOrdering()));
2549     Vals.push_back(cast<AtomicCmpXchgInst>(I).isWeak());
2550     break;
2551   case Instruction::AtomicRMW:
2552     Code = bitc::FUNC_CODE_INST_ATOMICRMW;
2553     pushValueAndType(I.getOperand(0), InstID, Vals); // ptrty + ptr
2554     pushValue(I.getOperand(1), InstID, Vals);        // val.
2555     Vals.push_back(
2556         getEncodedRMWOperation(cast<AtomicRMWInst>(I).getOperation()));
2557     Vals.push_back(cast<AtomicRMWInst>(I).isVolatile());
2558     Vals.push_back(getEncodedOrdering(cast<AtomicRMWInst>(I).getOrdering()));
2559     Vals.push_back(
2560         getEncodedSyncScopeID(cast<AtomicRMWInst>(I).getSyncScopeID()));
2561     break;
2562   case Instruction::Fence:
2563     Code = bitc::FUNC_CODE_INST_FENCE;
2564     Vals.push_back(getEncodedOrdering(cast<FenceInst>(I).getOrdering()));
2565     Vals.push_back(getEncodedSyncScopeID(cast<FenceInst>(I).getSyncScopeID()));
2566     break;
2567   case Instruction::Call: {
2568     const CallInst &CI = cast<CallInst>(I);
2569     FunctionType *FTy = CI.getFunctionType();
2570 
2571     Code = bitc::FUNC_CODE_INST_CALL;
2572 
2573     Vals.push_back(VE.getAttributeListID(CI.getAttributes()));
2574     Vals.push_back((CI.getCallingConv() << 1) | unsigned(CI.isTailCall()) |
2575                    unsigned(CI.isMustTailCall()) << 14 | 1 << 15);
2576     Vals.push_back(getGlobalObjectValueTypeID(FTy, CI.getCalledFunction()));
2577     pushValueAndType(CI.getCalledOperand(), InstID, Vals); // Callee
2578 
2579     // Emit value #'s for the fixed parameters.
2580     for (unsigned i = 0, e = FTy->getNumParams(); i != e; ++i) {
2581       // Check for labels (can happen with asm labels).
2582       if (FTy->getParamType(i)->isLabelTy())
2583         Vals.push_back(VE.getValueID(CI.getArgOperand(i)));
2584       else
2585         pushValue(CI.getArgOperand(i), InstID, Vals); // fixed param.
2586     }
2587 
2588     // Emit type/value pairs for varargs params.
2589     if (FTy->isVarArg()) {
2590       for (unsigned i = FTy->getNumParams(), e = CI.arg_size(); i != e; ++i)
2591         pushValueAndType(CI.getArgOperand(i), InstID, Vals); // varargs
2592     }
2593     break;
2594   }
2595   case Instruction::VAArg:
2596     Code = bitc::FUNC_CODE_INST_VAARG;
2597     Vals.push_back(getTypeID(I.getOperand(0)->getType())); // valistty
2598     pushValue(I.getOperand(0), InstID, Vals);              // valist.
2599     Vals.push_back(getTypeID(I.getType()));                // restype.
2600     break;
2601   }
2602 
2603   Stream.EmitRecord(Code, Vals, AbbrevToUse);
2604   Vals.clear();
2605 }
2606 
2607 // Emit names for globals/functions etc.
2608 void DXILBitcodeWriter::writeFunctionLevelValueSymbolTable(
2609     const ValueSymbolTable &VST) {
2610   if (VST.empty())
2611     return;
2612   Stream.EnterSubblock(bitc::VALUE_SYMTAB_BLOCK_ID, 4);
2613 
2614   SmallVector<unsigned, 64> NameVals;
2615 
2616   // HLSL Change
2617   // Read the named values from a sorted list instead of the original list
2618   // to ensure the binary is the same no matter what values ever existed.
2619   SmallVector<const ValueName *, 16> SortedTable;
2620 
2621   for (auto &VI : VST) {
2622     SortedTable.push_back(VI.second->getValueName());
2623   }
2624   // The keys are unique, so there shouldn't be stability issues.
2625   llvm::sort(SortedTable, [](const ValueName *A, const ValueName *B) {
2626     return A->first() < B->first();
2627   });
2628 
2629   for (const ValueName *SI : SortedTable) {
2630     auto &Name = *SI;
2631 
2632     // Figure out the encoding to use for the name.
2633     bool is7Bit = true;
2634     bool isChar6 = true;
2635     for (const char *C = Name.getKeyData(), *E = C + Name.getKeyLength();
2636          C != E; ++C) {
2637       if (isChar6)
2638         isChar6 = BitCodeAbbrevOp::isChar6(*C);
2639       if ((unsigned char)*C & 128) {
2640         is7Bit = false;
2641         break; // don't bother scanning the rest.
2642       }
2643     }
2644 
2645     unsigned AbbrevToUse = VST_ENTRY_8_ABBREV;
2646 
2647     // VST_ENTRY:   [valueid, namechar x N]
2648     // VST_BBENTRY: [bbid, namechar x N]
2649     unsigned Code;
2650     if (isa<BasicBlock>(SI->getValue())) {
2651       Code = bitc::VST_CODE_BBENTRY;
2652       if (isChar6)
2653         AbbrevToUse = VST_BBENTRY_6_ABBREV;
2654     } else {
2655       Code = bitc::VST_CODE_ENTRY;
2656       if (isChar6)
2657         AbbrevToUse = VST_ENTRY_6_ABBREV;
2658       else if (is7Bit)
2659         AbbrevToUse = VST_ENTRY_7_ABBREV;
2660     }
2661 
2662     NameVals.push_back(VE.getValueID(SI->getValue()));
2663     for (const char *P = Name.getKeyData(),
2664                     *E = Name.getKeyData() + Name.getKeyLength();
2665          P != E; ++P)
2666       NameVals.push_back((unsigned char)*P);
2667 
2668     // Emit the finished record.
2669     Stream.EmitRecord(Code, NameVals, AbbrevToUse);
2670     NameVals.clear();
2671   }
2672   Stream.ExitBlock();
2673 }
2674 
2675 void DXILBitcodeWriter::writeUseList(UseListOrder &&Order) {
2676   assert(Order.Shuffle.size() >= 2 && "Shuffle too small");
2677   unsigned Code;
2678   if (isa<BasicBlock>(Order.V))
2679     Code = bitc::USELIST_CODE_BB;
2680   else
2681     Code = bitc::USELIST_CODE_DEFAULT;
2682 
2683   SmallVector<uint64_t, 64> Record(Order.Shuffle.begin(), Order.Shuffle.end());
2684   Record.push_back(VE.getValueID(Order.V));
2685   Stream.EmitRecord(Code, Record);
2686 }
2687 
2688 void DXILBitcodeWriter::writeUseListBlock(const Function *F) {
2689   auto hasMore = [&]() {
2690     return !VE.UseListOrders.empty() && VE.UseListOrders.back().F == F;
2691   };
2692   if (!hasMore())
2693     // Nothing to do.
2694     return;
2695 
2696   Stream.EnterSubblock(bitc::USELIST_BLOCK_ID, 3);
2697   while (hasMore()) {
2698     writeUseList(std::move(VE.UseListOrders.back()));
2699     VE.UseListOrders.pop_back();
2700   }
2701   Stream.ExitBlock();
2702 }
2703 
2704 /// Emit a function body to the module stream.
2705 void DXILBitcodeWriter::writeFunction(const Function &F) {
2706   Stream.EnterSubblock(bitc::FUNCTION_BLOCK_ID, 4);
2707   VE.incorporateFunction(F);
2708 
2709   SmallVector<unsigned, 64> Vals;
2710 
2711   // Emit the number of basic blocks, so the reader can create them ahead of
2712   // time.
2713   Vals.push_back(VE.getBasicBlocks().size());
2714   Stream.EmitRecord(bitc::FUNC_CODE_DECLAREBLOCKS, Vals);
2715   Vals.clear();
2716 
2717   // If there are function-local constants, emit them now.
2718   unsigned CstStart, CstEnd;
2719   VE.getFunctionConstantRange(CstStart, CstEnd);
2720   writeConstants(CstStart, CstEnd, false);
2721 
2722   // If there is function-local metadata, emit it now.
2723   writeFunctionMetadata(F);
2724 
2725   // Keep a running idea of what the instruction ID is.
2726   unsigned InstID = CstEnd;
2727 
2728   bool NeedsMetadataAttachment = F.hasMetadata();
2729 
2730   DILocation *LastDL = nullptr;
2731 
2732   // Finally, emit all the instructions, in order.
2733   for (Function::const_iterator BB = F.begin(), E = F.end(); BB != E; ++BB)
2734     for (BasicBlock::const_iterator I = BB->begin(), E = BB->end(); I != E;
2735          ++I) {
2736       writeInstruction(*I, InstID, Vals);
2737 
2738       if (!I->getType()->isVoidTy())
2739         ++InstID;
2740 
2741       // If the instruction has metadata, write a metadata attachment later.
2742       NeedsMetadataAttachment |= I->hasMetadataOtherThanDebugLoc();
2743 
2744       // If the instruction has a debug location, emit it.
2745       DILocation *DL = I->getDebugLoc();
2746       if (!DL)
2747         continue;
2748 
2749       if (DL == LastDL) {
2750         // Just repeat the same debug loc as last time.
2751         Stream.EmitRecord(bitc::FUNC_CODE_DEBUG_LOC_AGAIN, Vals);
2752         continue;
2753       }
2754 
2755       Vals.push_back(DL->getLine());
2756       Vals.push_back(DL->getColumn());
2757       Vals.push_back(VE.getMetadataOrNullID(DL->getScope()));
2758       Vals.push_back(VE.getMetadataOrNullID(DL->getInlinedAt()));
2759       Stream.EmitRecord(bitc::FUNC_CODE_DEBUG_LOC, Vals);
2760       Vals.clear();
2761 
2762       LastDL = DL;
2763     }
2764 
2765   // Emit names for all the instructions etc.
2766   if (auto *Symtab = F.getValueSymbolTable())
2767     writeFunctionLevelValueSymbolTable(*Symtab);
2768 
2769   if (NeedsMetadataAttachment)
2770     writeFunctionMetadataAttachment(F);
2771 
2772   writeUseListBlock(&F);
2773   VE.purgeFunction();
2774   Stream.ExitBlock();
2775 }
2776 
2777 // Emit blockinfo, which defines the standard abbreviations etc.
2778 void DXILBitcodeWriter::writeBlockInfo() {
2779   // We only want to emit block info records for blocks that have multiple
2780   // instances: CONSTANTS_BLOCK, FUNCTION_BLOCK and VALUE_SYMTAB_BLOCK.
2781   // Other blocks can define their abbrevs inline.
2782   Stream.EnterBlockInfoBlock();
2783 
2784   { // 8-bit fixed-width VST_ENTRY/VST_BBENTRY strings.
2785     auto Abbv = std::make_shared<BitCodeAbbrev>();
2786     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 3));
2787     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
2788     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
2789     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 8));
2790     if (Stream.EmitBlockInfoAbbrev(bitc::VALUE_SYMTAB_BLOCK_ID,
2791                                    std::move(Abbv)) != VST_ENTRY_8_ABBREV)
2792       assert(false && "Unexpected abbrev ordering!");
2793   }
2794 
2795   { // 7-bit fixed width VST_ENTRY strings.
2796     auto Abbv = std::make_shared<BitCodeAbbrev>();
2797     Abbv->Add(BitCodeAbbrevOp(bitc::VST_CODE_ENTRY));
2798     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
2799     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
2800     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 7));
2801     if (Stream.EmitBlockInfoAbbrev(bitc::VALUE_SYMTAB_BLOCK_ID,
2802                                    std::move(Abbv)) != VST_ENTRY_7_ABBREV)
2803       assert(false && "Unexpected abbrev ordering!");
2804   }
2805   { // 6-bit char6 VST_ENTRY strings.
2806     auto Abbv = std::make_shared<BitCodeAbbrev>();
2807     Abbv->Add(BitCodeAbbrevOp(bitc::VST_CODE_ENTRY));
2808     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
2809     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
2810     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Char6));
2811     if (Stream.EmitBlockInfoAbbrev(bitc::VALUE_SYMTAB_BLOCK_ID,
2812                                    std::move(Abbv)) != VST_ENTRY_6_ABBREV)
2813       assert(false && "Unexpected abbrev ordering!");
2814   }
2815   { // 6-bit char6 VST_BBENTRY strings.
2816     auto Abbv = std::make_shared<BitCodeAbbrev>();
2817     Abbv->Add(BitCodeAbbrevOp(bitc::VST_CODE_BBENTRY));
2818     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
2819     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
2820     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Char6));
2821     if (Stream.EmitBlockInfoAbbrev(bitc::VALUE_SYMTAB_BLOCK_ID,
2822                                    std::move(Abbv)) != VST_BBENTRY_6_ABBREV)
2823       assert(false && "Unexpected abbrev ordering!");
2824   }
2825 
2826   { // SETTYPE abbrev for CONSTANTS_BLOCK.
2827     auto Abbv = std::make_shared<BitCodeAbbrev>();
2828     Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_SETTYPE));
2829     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,
2830                               VE.computeBitsRequiredForTypeIndicies()));
2831     if (Stream.EmitBlockInfoAbbrev(bitc::CONSTANTS_BLOCK_ID, std::move(Abbv)) !=
2832         CONSTANTS_SETTYPE_ABBREV)
2833       assert(false && "Unexpected abbrev ordering!");
2834   }
2835 
2836   { // INTEGER abbrev for CONSTANTS_BLOCK.
2837     auto Abbv = std::make_shared<BitCodeAbbrev>();
2838     Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_INTEGER));
2839     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8));
2840     if (Stream.EmitBlockInfoAbbrev(bitc::CONSTANTS_BLOCK_ID, std::move(Abbv)) !=
2841         CONSTANTS_INTEGER_ABBREV)
2842       assert(false && "Unexpected abbrev ordering!");
2843   }
2844 
2845   { // CE_CAST abbrev for CONSTANTS_BLOCK.
2846     auto Abbv = std::make_shared<BitCodeAbbrev>();
2847     Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_CE_CAST));
2848     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 4)); // cast opc
2849     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,      // typeid
2850                               VE.computeBitsRequiredForTypeIndicies()));
2851     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 8)); // value id
2852 
2853     if (Stream.EmitBlockInfoAbbrev(bitc::CONSTANTS_BLOCK_ID, std::move(Abbv)) !=
2854         CONSTANTS_CE_CAST_Abbrev)
2855       assert(false && "Unexpected abbrev ordering!");
2856   }
2857   { // NULL abbrev for CONSTANTS_BLOCK.
2858     auto Abbv = std::make_shared<BitCodeAbbrev>();
2859     Abbv->Add(BitCodeAbbrevOp(bitc::CST_CODE_NULL));
2860     if (Stream.EmitBlockInfoAbbrev(bitc::CONSTANTS_BLOCK_ID, std::move(Abbv)) !=
2861         CONSTANTS_NULL_Abbrev)
2862       assert(false && "Unexpected abbrev ordering!");
2863   }
2864 
2865   // FIXME: This should only use space for first class types!
2866 
2867   { // INST_LOAD abbrev for FUNCTION_BLOCK.
2868     auto Abbv = std::make_shared<BitCodeAbbrev>();
2869     Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_LOAD));
2870     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // Ptr
2871     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,    // dest ty
2872                               VE.computeBitsRequiredForTypeIndicies()));
2873     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 4));   // Align
2874     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // volatile
2875     if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID, std::move(Abbv)) !=
2876         (unsigned)FUNCTION_INST_LOAD_ABBREV)
2877       assert(false && "Unexpected abbrev ordering!");
2878   }
2879   { // INST_BINOP abbrev for FUNCTION_BLOCK.
2880     auto Abbv = std::make_shared<BitCodeAbbrev>();
2881     Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_BINOP));
2882     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // LHS
2883     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // RHS
2884     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 4)); // opc
2885     if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID, std::move(Abbv)) !=
2886         (unsigned)FUNCTION_INST_BINOP_ABBREV)
2887       assert(false && "Unexpected abbrev ordering!");
2888   }
2889   { // INST_BINOP_FLAGS abbrev for FUNCTION_BLOCK.
2890     auto Abbv = std::make_shared<BitCodeAbbrev>();
2891     Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_BINOP));
2892     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // LHS
2893     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));   // RHS
2894     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 4)); // opc
2895     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 7)); // flags
2896     if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID, std::move(Abbv)) !=
2897         (unsigned)FUNCTION_INST_BINOP_FLAGS_ABBREV)
2898       assert(false && "Unexpected abbrev ordering!");
2899   }
2900   { // INST_CAST abbrev for FUNCTION_BLOCK.
2901     auto Abbv = std::make_shared<BitCodeAbbrev>();
2902     Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_CAST));
2903     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // OpVal
2904     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed,    // dest ty
2905                               VE.computeBitsRequiredForTypeIndicies()));
2906     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 4)); // opc
2907     if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID, std::move(Abbv)) !=
2908         (unsigned)FUNCTION_INST_CAST_ABBREV)
2909       assert(false && "Unexpected abbrev ordering!");
2910   }
2911 
2912   { // INST_RET abbrev for FUNCTION_BLOCK.
2913     auto Abbv = std::make_shared<BitCodeAbbrev>();
2914     Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_RET));
2915     if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID, std::move(Abbv)) !=
2916         (unsigned)FUNCTION_INST_RET_VOID_ABBREV)
2917       assert(false && "Unexpected abbrev ordering!");
2918   }
2919   { // INST_RET abbrev for FUNCTION_BLOCK.
2920     auto Abbv = std::make_shared<BitCodeAbbrev>();
2921     Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_RET));
2922     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6)); // ValID
2923     if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID, std::move(Abbv)) !=
2924         (unsigned)FUNCTION_INST_RET_VAL_ABBREV)
2925       assert(false && "Unexpected abbrev ordering!");
2926   }
2927   { // INST_UNREACHABLE abbrev for FUNCTION_BLOCK.
2928     auto Abbv = std::make_shared<BitCodeAbbrev>();
2929     Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_UNREACHABLE));
2930     if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID, std::move(Abbv)) !=
2931         (unsigned)FUNCTION_INST_UNREACHABLE_ABBREV)
2932       assert(false && "Unexpected abbrev ordering!");
2933   }
2934   {
2935     auto Abbv = std::make_shared<BitCodeAbbrev>();
2936     Abbv->Add(BitCodeAbbrevOp(bitc::FUNC_CODE_INST_GEP));
2937     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1));
2938     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, // dest ty
2939                               Log2_32_Ceil(VE.getTypes().size() + 1)));
2940     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Array));
2941     Abbv->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::VBR, 6));
2942     if (Stream.EmitBlockInfoAbbrev(bitc::FUNCTION_BLOCK_ID, std::move(Abbv)) !=
2943         (unsigned)FUNCTION_INST_GEP_ABBREV)
2944       assert(false && "Unexpected abbrev ordering!");
2945   }
2946 
2947   Stream.ExitBlock();
2948 }
2949 
2950 void DXILBitcodeWriter::writeModuleVersion() {
2951   // VERSION: [version#]
2952   Stream.EmitRecord(bitc::MODULE_CODE_VERSION, ArrayRef<unsigned>{1});
2953 }
2954 
2955 /// WriteModule - Emit the specified module to the bitstream.
2956 void DXILBitcodeWriter::write() {
2957   // The identification block is new since llvm-3.7, but the old bitcode reader
2958   // will skip it.
2959   // writeIdentificationBlock(Stream);
2960 
2961   Stream.EnterSubblock(bitc::MODULE_BLOCK_ID, 3);
2962 
2963   // It is redundant to fully-specify this here, but nice to make it explicit
2964   // so that it is clear the DXIL module version is different.
2965   DXILBitcodeWriter::writeModuleVersion();
2966 
2967   // Emit blockinfo, which defines the standard abbreviations etc.
2968   writeBlockInfo();
2969 
2970   // Emit information about attribute groups.
2971   writeAttributeGroupTable();
2972 
2973   // Emit information about parameter attributes.
2974   writeAttributeTable();
2975 
2976   // Emit information describing all of the types in the module.
2977   writeTypeTable();
2978 
2979   writeComdats();
2980 
2981   // Emit top-level description of module, including target triple, inline asm,
2982   // descriptors for global variables, and function prototype info.
2983   writeModuleInfo();
2984 
2985   // Emit constants.
2986   writeModuleConstants();
2987 
2988   // Emit metadata.
2989   writeModuleMetadataKinds();
2990 
2991   // Emit metadata.
2992   writeModuleMetadata();
2993 
2994   // Emit names for globals/functions etc.
2995   // DXIL uses the same format for module-level value symbol table as for the
2996   // function level table.
2997   writeFunctionLevelValueSymbolTable(M.getValueSymbolTable());
2998 
2999   // Emit module-level use-lists.
3000   writeUseListBlock(nullptr);
3001 
3002   // Emit function bodies.
3003   for (const Function &F : M)
3004     if (!F.isDeclaration())
3005       writeFunction(F);
3006 
3007   Stream.ExitBlock();
3008 }
3009