[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>
llvm-svn: 266446
diff --git a/llvm/test/DebugInfo/X86/earlydup-crash.ll b/llvm/test/DebugInfo/X86/earlydup-crash.ll
index 696d278..aa6f88f 100644
--- a/llvm/test/DebugInfo/X86/earlydup-crash.ll
+++ b/llvm/test/DebugInfo/X86/earlydup-crash.ll
@@ -46,9 +46,9 @@
!llvm.module.flags = !{!47}
!0 = !DILocalVariable(name: "frname_len", line: 517, scope: !1, file: !3, type: !38)
!1 = distinct !DILexicalBlock(line: 515, column: 0, file: !44, scope: !2)
-!2 = distinct !DISubprogram(name: "framework_construct_pathname", line: 515, isLocal: true, isDefinition: true, virtualIndex: 6, flags: DIFlagPrototyped, isOptimized: true, file: !44, scope: null, type: !5)
+!2 = distinct !DISubprogram(name: "framework_construct_pathname", line: 515, isLocal: true, isDefinition: true, virtualIndex: 6, flags: DIFlagPrototyped, isOptimized: true, unit: !4, file: !44, scope: null, type: !5)
!3 = !DIFile(filename: "darwin-c.c", directory: "/Users/espindola/llvm/build-llvm-gcc/gcc/../../llvm-gcc-4.2/gcc/config")
-!4 = distinct !DICompileUnit(language: DW_LANG_C89, producer: "4.2.1 (Based on Apple Inc. build 5658) (LLVM build)", isOptimized: true, emissionKind: FullDebug, file: !44, enums: !46, retainedTypes: !46, subprograms: !45)
+!4 = distinct !DICompileUnit(language: DW_LANG_C89, producer: "4.2.1 (Based on Apple Inc. build 5658) (LLVM build)", isOptimized: true, emissionKind: FullDebug, file: !44, enums: !46, retainedTypes: !46)
!5 = !DISubroutineType(types: !6)
!6 = !{!7, !9, !11}
!7 = !DIDerivedType(tag: DW_TAG_pointer_type, size: 32, align: 32, file: !44, scope: !3, baseType: !8)
@@ -89,6 +89,5 @@
!42 = !DIFile(filename: "types.h", directory: "/usr/include/sys")
!43 = !DIFile(filename: "stddef.h", directory: "/Users/espindola/llvm/build-llvm-gcc/./prev-gcc/include")
!44 = !DIFile(filename: "darwin-c.c", directory: "/Users/espindola/llvm/build-llvm-gcc/gcc/../../llvm-gcc-4.2/gcc/config")
-!45 = !{!2}
!46 = !{}
!47 = !{i32 1, !"Debug Info Version", i32 3}