Adjust "Source Lang Literal" logic to support multiple CompileUnits (#2098)

This commit changes "Source Lang Literal" flag from simple a scalar value
to a vector of pairs: (compile unit, source language).

Author: mateuszchudyk

lib/SPIRV/SPIRVToLLVMDbgTran.cpp

@@ -167,6 +167,34 @@ DIScope *SPIRVToLLVMDbgTran::getScope(const SPIRVEntry *ScopeInst) {
   return transDebugInst<DIScope>(static_cast<const SPIRVExtInst *>(ScopeInst));
 }
 
+void SPIRVToLLVMDbgTran::appendToSourceLangLiteral(DICompileUnit *CompileUnit,
+                                                   SPIRVWord SourceLang) {
+  if (!M->getModuleFlag("Source Lang Literal")) {
+    M->addModuleFlag(llvm::Module::Warning, "Source Lang Literal",
+                     MDTuple::get(M->getContext(), {}));
+  }
+  auto *SourceLangLiteral =
+      dyn_cast<MDTuple>(M->getModuleFlag("Source Lang Literal"));
+
+  // Copy old content
+  SmallVector<Metadata *, 4> Nodes;
+  for (auto &Node : SourceLangLiteral->operands()) {
+    Nodes.push_back(Node);
+  }
+
+  // Add new entry
+  Nodes.push_back(MDTuple::get(
+      M->getContext(), SmallVector<Metadata *, 2>{
+                           CompileUnit,
+                           ConstantAsMetadata::get(ConstantInt::get(
+                               Type::getInt32Ty(M->getContext()), SourceLang)),
+                       }));
+
+  // Update
+  M->setModuleFlag(llvm::Module::Warning, "Source Lang Literal",
+                   MDTuple::get(M->getContext(), Nodes));
+}
+
 DICompileUnit *
 SPIRVToLLVMDbgTran::transCompilationUnit(const SPIRVExtInst *DebugInst,
                                          const std::string CompilerVersion,
@@ -191,6 +219,8 @@ SPIRVToLLVMDbgTran::transCompilationUnit(const SPIRVExtInst *DebugInst,
   }
   SPIRVWord SourceLang =
       getConstantValueOrLiteral(Ops, LanguageIdx, DebugInst->getExtSetKind());
+  SPIRVWord OriginalSourceLang = SourceLang;
+  bool InvalidSourceLang = false;
   if (DebugInst->getExtSetKind() == SPIRVEIS_NonSemantic_Shader_DebugInfo_200) {
     SourceLang = convertSPIRVSourceLangToDWARFNonSemanticDbgInfo(SourceLang);
   } else if (isSPIRVSourceLangValid(SourceLang)) {
@@ -199,8 +229,8 @@ SPIRVToLLVMDbgTran::transCompilationUnit(const SPIRVExtInst *DebugInst,
     // Some SPIR-V producers generate invalid source language value. In such
     // case the original value should be preserved in "Source Lang Literal"
     // module flag for later use by LLVM IR consumers.
-    M->addModuleFlag(llvm::Module::Warning, "Source Lang Literal", SourceLang);
     SourceLang = dwarf::DW_LANG_OpenCL;
+    InvalidSourceLang = true;
   }
 
   BuilderMap[DebugInst->getId()] = std::make_unique<DIBuilder>(*M);
@@ -218,20 +248,28 @@ SPIRVToLLVMDbgTran::transCompilationUnit(const SPIRVExtInst *DebugInst,
            DebugInst->getExtSetKind() ==
                SPIRVEIS_NonSemantic_Shader_DebugInfo_200);
 
-    return BuilderMap[DebugInst->getId()]->createCompileUnit(
+    auto *CompileUnit = BuilderMap[DebugInst->getId()]->createCompileUnit(
         SourceLang, getFile(Ops[SourceIdx]),
         DebugInst->getExtSetKind() == SPIRVEIS_NonSemantic_Shader_DebugInfo_100
             ? CompilerVersion
             : getString(Ops[ProducerIdx]),
         false, Flags, 0, StoragePath,
         DICompileUnit::DebugEmissionKind::FullDebug, BuildIdentifier);
+    if (InvalidSourceLang) {
+      appendToSourceLangLiteral(CompileUnit, OriginalSourceLang);
+    }
+    return CompileUnit;
   }
 
   // TODO: Remove this workaround once we switch to NonSemantic.Shader.* debug
   // info by default
   auto Producer = findModuleProducer();
-  return BuilderMap[DebugInst->getId()]->createCompileUnit(
+  auto *CompileUnit = BuilderMap[DebugInst->getId()]->createCompileUnit(
       SourceLang, getFile(Ops[SourceIdx]), Producer, false, Flags, 0);
+  if (InvalidSourceLang) {
+    appendToSourceLangLiteral(CompileUnit, OriginalSourceLang);
+  }
+  return CompileUnit;
 }
 
 DIBasicType *SPIRVToLLVMDbgTran::transTypeBasic(const SPIRVExtInst *DebugInst) {

lib/SPIRV/SPIRVToLLVMDbgTran.h

@@ -106,6 +106,9 @@ class SPIRVToLLVMDbgTran {
   MDNode *transDebugInlined(const SPIRVExtInst *Inst);
   MDNode *transDebugInlinedNonSemanticShader200(const SPIRVExtInst *Inst);
 
+  void appendToSourceLangLiteral(DICompileUnit *CompileUnit,
+                                 SPIRVWord SourceLang);
+
   DICompileUnit *transCompilationUnit(const SPIRVExtInst *DebugInst,
                                       const std::string CompilerVersion = "",
                                       const std::string Flags = "");

test/DebugInfo/InvalidSourceLanguageSPIRVtoLLVM.spvasm

@@ -36,5 +36,7 @@
                OpReturn
                OpFunctionEnd
 
-; CHECK: !{i32 2, !"Source Lang Literal", i32 42}
-; CHECK: !DICompileUnit(language: DW_LANG_OpenCL,
+; CHECK: {{![0-9]+}} = !{i32 2, !"Source Lang Literal", [[LIST:![0-9]+]]}
+; CHECK: [[LIST]] = !{[[ENTRY:![0-9]+]]}
+; CHECK: [[ENTRY]] = !{[[CU:![0-9]+]], i32 42}
+; CHECK: [[CU]] = distinct !DICompileUnit(language: DW_LANG_OpenCL