[llvm] [LLVM][DWARF] Add support for monolithic types in .debug_names (PR #68131)

[Fangrui Song via llvm-commits]

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@@ -0,0 +1,57 @@
+; This checks that .debug_names is not generated with split-dwarf + -fdebug-type-sections.
+
+; RUN: llc -mtriple=x86_64 -generate-type-units -dwarf-version=5 -filetype=obj -split-dwarf-file=mainTypes.dwo --split-dwarf-output=mainTypes.dwo %s -o %t
+; RUN: llvm-readelf --sections %t | FileCheck %s
+
+; CHECK-NOT: .debug_names
+
+; ModuleID = 'main.cpp'
+source_filename = "main.cpp"
+target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+%struct.Foo = type { ptr }
+
+; Function Attrs: mustprogress noinline norecurse nounwind optnone uwtable
+define dso_local noundef i32 @main() #0 !dbg !10 {
+entry:
+  %retval = alloca i32, align 4
+  %f = alloca %struct.Foo, align 8
+  store i32 0, ptr %retval, align 4
+  call void @llvm.dbg.declare(metadata ptr %f, metadata !15, metadata !DIExpression()), !dbg !21
+  ret i32 0, !dbg !22
+}
+
+; Function Attrs: nocallback nofree nosync nounwind speculatable willreturn memory(none)
+declare void @llvm.dbg.declare(metadata, metadata, metadata) #1
+
+attributes #0 = { mustprogress noinline norecurse nounwind optnone uwtable "frame-pointer"="all" "min-legal-vector-width"="0" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cmov,+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" }
+attributes #1 = { nocallback nofree nosync nounwind speculatable willreturn memory(none) }
+
+!llvm.dbg.cu = !{!0}
+!llvm.module.flags = !{!2, !3, !4, !5, !6, !7, !8}
+!llvm.ident = !{!9}
+
+!0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus_14, file: !1, producer: "clang version 18.0.0 (ssh://git.vip.facebook.com/data/gitrepos/osmeta/external/llvm-project 680deb27e25976d9b74ad7b48ec5cb96be0e44b6)", isOptimized: false, runtimeVersion: 0, splitDebugFilename: "main.dwo", emissionKind: FullDebug, splitDebugInlining: false)
+!1 = !DIFile(filename: "main.cpp", directory: "/home/ayermolo/local/tasks/T138552329/typeSmallSplit", checksumkind: CSK_MD5, checksum: "e5b402e9dbafe24c7adbb087d1f03549")
+!2 = !{i32 7, !"Dwarf Version", i32 5}
+!3 = !{i32 2, !"Debug Info Version", i32 3}
+!4 = !{i32 1, !"wchar_size", i32 4}
+!5 = !{i32 8, !"PIC Level", i32 2}
+!6 = !{i32 7, !"PIE Level", i32 2}
+!7 = !{i32 7, !"uwtable", i32 2}
+!8 = !{i32 7, !"frame-pointer", i32 2}
+!9 = !{!"clang version 18.0.0 (ssh://git.vip.facebook.com/data/gitrepos/osmeta/external/llvm-project 680deb27e25976d9b74ad7b48ec5cb96be0e44b6)"}
----------------
MaskRay wrote:

You may consider `-DLLVM_APPEND_VC_REV=OFF-DLLVM_APPEND_VC_REV=OFF` in the future :)

https://github.com/llvm/llvm-project/pull/68131