Fix transTypeComposite bug (#964)

* Fix transTypeComposite bug

This is a workaround to fix an error caused by DIBuilder which always creates
a node with the DW_TAG_struct_type tag for both class and structure.

Author: KornevNikita

lib/SPIRV/SPIRVToLLVMDbgTran.cpp

@@ -267,10 +267,12 @@ SPIRVToLLVMDbgTran::transTypeComposite(const SPIRVExtInst *DebugInst) {
   DICompositeType *CT = nullptr;
   switch (Ops[TagIdx]) {
   case SPIRVDebug::Class:
-    CT = Builder.createClassType(
-        ParentScope, Name, File, LineNo, Size, Align, 0, Flags, DerivedFrom,
-        DINodeArray() /*elements*/, nullptr /*VTableHolder*/,
-        nullptr /*TemplateParams*/, Identifier);
+    // TODO: should be replaced with createClassType, when bug with creating
+    // ClassType with llvm::dwarf::DW_TAG_struct_type tag will be fixed
+    CT = Builder.createReplaceableCompositeType(
+        llvm::dwarf::DW_TAG_class_type, Name, ParentScope, File, LineNo, 0,
+        Size, Align, Flags, Identifier);
+    CT = llvm::MDNode::replaceWithDistinct(llvm::TempDICompositeType(CT));
     break;
   case SPIRVDebug::Structure:
     CT = Builder.createStructType(ParentScope, Name, File, LineNo, Size, Align,

test/DebugInfo/TransTypeCompositeCaseClass_.ll

@@ -0,0 +1,73 @@
+; Source code:
+; class A {};
+; struct B {};
+
+; int main() {
+;   A a;
+;   B b;
+;   return 0;
+; }
+
+; RUN: llvm-as %s -o %t.bc
+; RUN: llvm-spirv %t.bc -o %t.spv
+; RUN: llvm-spirv -r %t.spv -o %t.rev.bc
+; RUN: llvm-dis < %t.rev.bc | FileCheck %s --check-prefix=CHECK-LLVM
+
+; ModuleID = 'main.cpp'
+source_filename = "main.cpp"
+target datalayout = "e-i64:64-v16:16-v24:32-v32:32-v48:64-v96:128-v192:256-v256:256-v512:512-v1024:1024-n8:16:32:64"
+target triple = "spir64"
+
+%class.A = type { i8 }
+%struct.B = type { i8 }
+
+; Function Attrs: noinline norecurse nounwind optnone mustprogress
+define dso_local i32 @main() #0 !dbg !6 {
+entry:
+  %retval = alloca i32, align 4
+  %a = alloca %class.A, align 1
+  %b = alloca %struct.B, align 1
+  store i32 0, i32* %retval, align 4
+  call void @llvm.dbg.declare(metadata %class.A* %a, metadata !11, metadata !DIExpression()), !dbg !13
+  call void @llvm.dbg.declare(metadata %struct.B* %b, metadata !14, metadata !DIExpression()), !dbg !16
+  ret i32 0, !dbg !17
+}
+
+; Function Attrs: nofree nosync nounwind readnone speculatable willreturn
+declare void @llvm.dbg.declare(metadata, metadata, metadata) #1
+
+attributes #0 = { noinline norecurse nounwind optnone mustprogress "disable-tail-calls"="false" "frame-pointer"="none" "less-precise-fpmad"="false" "min-legal-vector-width"="0" "no-infs-fp-math"="false" "no-jump-tables"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "unsafe-fp-math"="false" "use-soft-float"="false" }
+attributes #1 = { nofree nosync nounwind readnone speculatable willreturn }
+
+!llvm.dbg.cu = !{!0}
+!llvm.module.flags = !{!3, !4}
+!opencl.used.extensions = !{!2}
+!opencl.used.optional.core.features = !{!2}
+!opencl.compiler.options = !{!2}
+!llvm.ident = !{!5}
+
+; CHECK-LLVM: !DICompositeType
+; CHECK-LLVM-SAME: tag: DW_TAG_class_type
+; CHECK-LLVM-SAME: name: "A"
+; CHECK-LLVM: !DICompositeType
+; CHECK-LLVM-SAME: tag: DW_TAG_structure_type
+; CHECK-LLVM-SAME: name: "B"
+
+!0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus_14, file: !1, producer: "clang version 13.0.0 (https://github.com/llvm/llvm-project.git 16a50c9e642fd085e5ceb68c403b71b5b2e0607c)", isOptimized: false, runtimeVersion: 0, emissionKind: FullDebug, enums: !2, nameTableKind: None)
+!1 = !DIFile(filename: "<stdin>", directory: "/export/users")
+!2 = !{}
+!3 = !{i32 2, !"Debug Info Version", i32 3}
+!4 = !{i32 1, !"wchar_size", i32 4}
+!5 = !{!"clang version 13.0.0 (https://github.com/llvm/llvm-project.git 16a50c9e642fd085e5ceb68c403b71b5b2e0607c)"}
+!6 = distinct !DISubprogram(name: "main", scope: !7, file: !7, line: 4, type: !8, scopeLine: 4, flags: DIFlagPrototyped, spFlags: DISPFlagDefinition, unit: !0, retainedNodes: !2)
+!7 = !DIFile(filename: "main.cpp", directory: "/export/users")
+!8 = !DISubroutineType(types: !9)
+!9 = !{!10}
+!10 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
+!11 = !DILocalVariable(name: "a", scope: !6, file: !7, line: 5, type: !12)
+!12 = distinct !DICompositeType(tag: DW_TAG_class_type, name: "A", file: !7, line: 1, size: 8, flags: DIFlagTypePassByValue, elements: !2, identifier: "_ZTS1A")
+!13 = !DILocation(line: 5, column: 7, scope: !6)
+!14 = !DILocalVariable(name: "b", scope: !6, file: !7, line: 6, type: !15)
+!15 = distinct !DICompositeType(tag: DW_TAG_structure_type, name: "B", file: !7, line: 2, size: 8, flags: DIFlagTypePassByValue, elements: !2, identifier: "_ZTS1B")
+!16 = !DILocation(line: 6, column: 7, scope: !6)
+!17 = !DILocation(line: 7, column: 5, scope: !6)