llvm/test/Linker/2011-08-18-unique-debug-type2.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

27 lines
1.2 KiB
LLVM

; This file is for use with 2011-08-10-unique-debug-type.ll
; RUN: true
target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64"
target triple = "x86_64-apple-macosx10.7.0"
define i32 @bar() nounwind uwtable ssp !dbg !5 {
entry:
ret i32 2, !dbg !10
}
!llvm.dbg.cu = !{!0}
!llvm.module.flags = !{!13}
!0 = distinct !DICompileUnit(language: DW_LANG_C99, producer: "clang version 3.0 (trunk 137954)", isOptimized: true, emissionKind: FullDebug, file: !12, enums: !2, retainedTypes: !2, globals: !2)
!1 = !{!2}
!2 = !{}
!5 = distinct !DISubprogram(name: "bar", line: 1, isLocal: false, isDefinition: true, virtualIndex: 6, isOptimized: false, unit: !0, file: !12, scope: !6, type: !7)
!6 = !DIFile(filename: "two.c", directory: "/private/tmp")
!7 = !DISubroutineType(types: !8)
!8 = !{!9}
!9 = !DIBasicType(tag: DW_TAG_base_type, name: "int", size: 32, align: 32, encoding: DW_ATE_signed)
!10 = !DILocation(line: 1, column: 13, scope: !11)
!11 = distinct !DILexicalBlock(line: 1, column: 11, file: !12, scope: !5)
!12 = !DIFile(filename: "two.c", directory: "/private/tmp")
!13 = !{i32 1, !"Debug Info Version", i32 3}