DI: Reverse direction of subprogram -> function edge.
Previously, subprograms contained a metadata reference to the function they
described. Because most clients need to get or set a subprogram for a given
function rather than the other way around, this created unneeded inefficiency.
For example, many passes needed to call the function llvm::makeSubprogramMap()
to build a mapping from functions to subprograms, and the IR linker needed to
fix up function references in a way that caused quadratic complexity in the IR
linking phase of LTO.
This change reverses the direction of the edge by storing the subprogram as
function-level metadata and removing DISubprogram's function field.
Since this is an IR change, a bitcode upgrade has been provided.
Fixes PR23367. An upgrade script for textual IR for out-of-tree clients is
attached to the PR.
Differential Revision: http://reviews.llvm.org/D14265
llvm-svn: 252219
diff --git a/llvm/test/DebugInfo/X86/reference-argument.ll b/llvm/test/DebugInfo/X86/reference-argument.ll
index 7efe5c5..d45d04d 100644
--- a/llvm/test/DebugInfo/X86/reference-argument.ll
+++ b/llvm/test/DebugInfo/X86/reference-argument.ll
@@ -16,7 +16,7 @@
declare void @llvm.dbg.declare(metadata, metadata, metadata) #1
declare i32 @main()
; Function Attrs: nounwind ssp uwtable
-define linkonce_odr void @_ZN1A3fooE4SVal(%class.A* %this, %class.SVal* %v) nounwind ssp uwtable align 2 {
+define linkonce_odr void @_ZN1A3fooE4SVal(%class.A* %this, %class.SVal* %v) nounwind ssp uwtable align 2 !dbg !35 {
entry:
%this.addr = alloca %class.A*, align 8
store %class.A* %this, %class.A** %this.addr, align 8
@@ -36,7 +36,7 @@
!1 = !DIFile(filename: "aggregate-indirect-arg.cpp", directory: "")
!2 = !{}
!3 = !{!4, !29, !33, !34, !35}
-!4 = distinct !DISubprogram(name: "bar", linkageName: "_Z3barR4SVal", line: 19, isLocal: false, isDefinition: true, virtualIndex: 6, flags: DIFlagPrototyped, isOptimized: false, scopeLine: 19, file: !1, scope: !5, type: !6, function: void (%class.SVal*)* @_Z3barR4SVal, variables: !2)
+!4 = distinct !DISubprogram(name: "bar", linkageName: "_Z3barR4SVal", line: 19, isLocal: false, isDefinition: true, virtualIndex: 6, flags: DIFlagPrototyped, isOptimized: false, scopeLine: 19, file: !1, scope: !5, type: !6, variables: !2)
!5 = !DIFile(filename: "aggregate-indirect-arg.cpp", directory: "")
!6 = !DISubroutineType(types: !7)
!7 = !{null, !8}
@@ -58,13 +58,13 @@
!25 = !{null, !19, !26}
!26 = !DIDerivedType(tag: DW_TAG_reference_type, baseType: !27)
!27 = !DIDerivedType(tag: DW_TAG_const_type, baseType: !9)
-!29 = distinct !DISubprogram(name: "main", line: 25, isLocal: false, isDefinition: true, virtualIndex: 6, flags: DIFlagPrototyped, isOptimized: false, scopeLine: 25, file: !1, scope: !5, type: !30, function: i32 ()* @main, variables: !2)
+!29 = distinct !DISubprogram(name: "main", line: 25, isLocal: false, isDefinition: true, virtualIndex: 6, flags: DIFlagPrototyped, isOptimized: false, scopeLine: 25, file: !1, scope: !5, type: !30, variables: !2)
!30 = !DISubroutineType(types: !31)
!31 = !{!32}
!32 = !DIBasicType(tag: DW_TAG_base_type, name: "int", size: 32, align: 32, encoding: DW_ATE_signed)
-!33 = distinct !DISubprogram(name: "~SVal", linkageName: "_ZN4SValD1Ev", line: 14, isLocal: false, isDefinition: true, virtualIndex: 6, flags: DIFlagPrototyped, isOptimized: false, scopeLine: 14, file: !1, scope: null, type: !17, function: void (%class.SVal*)* @_ZN4SValD1Ev, declaration: !16, variables: !2)
-!34 = distinct !DISubprogram(name: "~SVal", linkageName: "_ZN4SValD2Ev", line: 14, isLocal: false, isDefinition: true, virtualIndex: 6, flags: DIFlagPrototyped, isOptimized: false, scopeLine: 14, file: !1, scope: null, type: !17, function: void (%class.SVal*)* @_ZN4SValD2Ev, declaration: !16, variables: !2)
-!35 = distinct !DISubprogram(name: "foo", linkageName: "_ZN1A3fooE4SVal", line: 22, isLocal: false, isDefinition: true, virtualIndex: 6, flags: DIFlagPrototyped, isOptimized: false, scopeLine: 22, file: !1, scope: null, type: !36, function: void (%class.A*, %class.SVal*)* @_ZN1A3fooE4SVal, declaration: !41, variables: !2)
+!33 = distinct !DISubprogram(name: "~SVal", linkageName: "_ZN4SValD1Ev", line: 14, isLocal: false, isDefinition: true, virtualIndex: 6, flags: DIFlagPrototyped, isOptimized: false, scopeLine: 14, file: !1, scope: null, type: !17, declaration: !16, variables: !2)
+!34 = distinct !DISubprogram(name: "~SVal", linkageName: "_ZN4SValD2Ev", line: 14, isLocal: false, isDefinition: true, virtualIndex: 6, flags: DIFlagPrototyped, isOptimized: false, scopeLine: 14, file: !1, scope: null, type: !17, declaration: !16, variables: !2)
+!35 = distinct !DISubprogram(name: "foo", linkageName: "_ZN1A3fooE4SVal", line: 22, isLocal: false, isDefinition: true, virtualIndex: 6, flags: DIFlagPrototyped, isOptimized: false, scopeLine: 22, file: !1, scope: null, type: !36, declaration: !41, variables: !2)
!36 = !DISubroutineType(types: !37)
!37 = !{null, !38, !9}
!38 = !DIDerivedType(tag: DW_TAG_pointer_type, size: 64, align: 64, flags: DIFlagArtificial | DIFlagObjectPointer, baseType: !39)