llvm/test/CodeGen/Inputs/DbgValueOtherTargets.ll
Adrian Prantl 4eeaa0da04 [PR27284] Reverse the ownership between DICompileUnit and DISubprogram.
Currently each Function points to a DISubprogram and DISubprogram has a
scope field. For member functions the scope is a DICompositeType. DIScopes
point to the DICompileUnit to facilitate type uniquing.

Distinct DISubprograms (with isDefinition: true) are not part of the type
hierarchy and cannot be uniqued. This change removes the subprograms
list from DICompileUnit and instead adds a pointer to the owning compile
unit to distinct DISubprograms. This would make it easy for ThinLTO to
strip unneeded DISubprograms and their transitively referenced debug info.

Motivation
----------

Materializing DISubprograms is currently the most expensive operation when
doing a ThinLTO build of clang.

We want the DISubprogram to be stored in a separate Bitcode block (or the
same block as the function body) so we can avoid having to expensively
deserialize all DISubprograms together with the global metadata. If a
function has been inlined into another subprogram we need to store a
reference the block containing the inlined subprogram.

Attached to https://llvm.org/bugs/show_bug.cgi?id=27284 is a python script
that updates LLVM IR testcases to the new format.

http://reviews.llvm.org/D19034
<rdar://problem/25256815>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@266446 91177308-0d34-0410-b5e6-96231b3b80d8
2016-04-15 15:57:41 +00:00

30 lines
1.4 KiB
LLVM

; Check that DEBUG_VALUE comments come through on a variety of targets.
define i32 @main() nounwind ssp !dbg !0 {
entry:
; CHECK: DEBUG_VALUE
call void @llvm.dbg.value(metadata i32 0, i64 0, metadata !7, metadata !DIExpression()), !dbg !9
ret i32 0, !dbg !10
}
declare void @llvm.dbg.declare(metadata, metadata, metadata) nounwind readnone
declare void @llvm.dbg.value(metadata, i64, metadata, metadata) nounwind readnone
!llvm.dbg.cu = !{!2}
!llvm.module.flags = !{!13}
!0 = distinct !DISubprogram(name: "main", line: 2, isLocal: false, isDefinition: true, virtualIndex: 6, isOptimized: false, unit: !2, file: !12, scope: !1, type: !3)
!1 = !DIFile(filename: "/tmp/x.c", directory: "/Users/manav")
!2 = distinct !DICompileUnit(language: DW_LANG_C99, producer: "clang version 2.9 (trunk 120996)", isOptimized: false, emissionKind: FullDebug, file: !12, enums: !6, retainedTypes: !6)
!3 = !DISubroutineType(types: !4)
!4 = !{!5}
!5 = !DIBasicType(tag: DW_TAG_base_type, name: "int", size: 32, align: 32, encoding: DW_ATE_signed)
!6 = !{}
!7 = !DILocalVariable(name: "i", line: 3, scope: !8, file: !1, type: !5)
!8 = distinct !DILexicalBlock(line: 2, column: 12, file: !12, scope: !0)
!9 = !DILocation(line: 3, column: 11, scope: !8)
!10 = !DILocation(line: 4, column: 2, scope: !8)
!12 = !DIFile(filename: "/tmp/x.c", directory: "/Users/manav")
!13 = !{i32 1, !"Debug Info Version", i32 3}