DI: Require subprogram definitions to be distinct

As a follow-up to r246098, require `DISubprogram` definitions
(`isDefinition: true`) to be 'distinct'.  Specifically, add an assembler
check, a verifier check, and bitcode upgrading logic to combat testcase
bitrot after the `DIBuilder` change.

While working on the testcases, I realized that
test/Linker/subprogram-linkonce-weak-odr.ll isn't relevant anymore.  Its
purpose was to check for a corner case in PR22792 where two subprogram
definitions match exactly and share the same metadata node.  The new
verifier check, requiring that subprogram definitions are 'distinct',
precludes that possibility.

I updated almost all the IR with the following script:

    git grep -l -E -e '= !DISubprogram\(.* isDefinition: true' |
    grep -v test/Bitcode |
    xargs sed -i '' -e 's/= \(!DISubprogram(.*, isDefinition: true\)/= distinct \1/'

Likely some variant of would work for out-of-tree testcases.

llvm-svn: 246327

1 files changed, 3 insertions, 3 deletions

diff --git a/llvm/test/DebugInfo/incorrect-variable-debugloc.ll b/llvm/test/DebugInfo/incorrect-variable-debugloc.ll
index cff254ee3c6..b5787923d1c 100644
--- a/llvm/test/DebugInfo/incorrect-variable-debugloc.ll
+++ b/llvm/test/DebugInfo/incorrect-variable-debugloc.ll
@@ -358,17 +358,17 @@ attributes #3 = { nounwind readnone }
 !19 = !{null, !20}
 !20 = !DIDerivedType(tag: DW_TAG_pointer_type, size: 64, align: 64, flags: DIFlagArtificial | DIFlagObjectPointer, baseType: !"_ZTS1B")
 !21 = !{!22, !28, !32}
-!22 = !DISubprogram(name: "fn1", linkageName: "_Z3fn1v", line: 16, isLocal: false, isDefinition: true, virtualIndex: 6, flags: DIFlagPrototyped, isOptimized: true, scopeLine: 16, file: !5, scope: !23, type: !24, function: i32 ()* @_Z3fn1v, variables: !26)
+!22 = distinct !DISubprogram(name: "fn1", linkageName: "_Z3fn1v", line: 16, isLocal: false, isDefinition: true, virtualIndex: 6, flags: DIFlagPrototyped, isOptimized: true, scopeLine: 16, file: !5, scope: !23, type: !24, function: i32 ()* @_Z3fn1v, variables: !26)
 !23 = !DIFile(filename: "incorrect-variable-debug-loc.cpp", directory: "/tmp/dbginfo")
 !24 = !DISubroutineType(types: !25)
 !25 = !{!8}
 !26 = !{!27}
 !27 = !DILocalVariable(name: "A", line: 17, scope: !22, file: !23, type: !"_ZTS1C")
-!28 = !DISubprogram(name: "m_fn3", linkageName: "_ZN1C5m_fn3Ev", line: 21, isLocal: false, isDefinition: true, virtualIndex: 6, flags: DIFlagPrototyped, isOptimized: true, scopeLine: 21, file: !5, scope: !"_ZTS1C", type: !11, function: void (%struct.C*)* @_ZN1C5m_fn3Ev, declaration: !10, variables: !29)
+!28 = distinct !DISubprogram(name: "m_fn3", linkageName: "_ZN1C5m_fn3Ev", line: 21, isLocal: false, isDefinition: true, virtualIndex: 6, flags: DIFlagPrototyped, isOptimized: true, scopeLine: 21, file: !5, scope: !"_ZTS1C", type: !11, function: void (%struct.C*)* @_ZN1C5m_fn3Ev, declaration: !10, variables: !29)
 !29 = !{!30}
 !30 = !DILocalVariable(name: "this", arg: 1, flags: DIFlagArtificial | DIFlagObjectPointer, scope: !28, type: !31)
 !31 = !DIDerivedType(tag: DW_TAG_pointer_type, size: 64, align: 64, baseType: !"_ZTS1C")
-!32 = !DISubprogram(name: "m_fn2", linkageName: "_ZN1B5m_fn2Ev", line: 6, isLocal: false, isDefinition: true, virtualIndex: 6, flags: DIFlagPrototyped, isOptimized: true, scopeLine: 6, file: !5, scope: !"_ZTS1B", type: !18, declaration: !17, variables: !33)
+!32 = distinct !DISubprogram(name: "m_fn2", linkageName: "_ZN1B5m_fn2Ev", line: 6, isLocal: false, isDefinition: true, virtualIndex: 6, flags: DIFlagPrototyped, isOptimized: true, scopeLine: 6, file: !5, scope: !"_ZTS1B", type: !18, declaration: !17, variables: !33)
 !33 = !{!34}
 !34 = !DILocalVariable(name: "this", arg: 1, flags: DIFlagArtificial | DIFlagObjectPointer, scope: !32, type: !35)
 !35 = !DIDerivedType(tag: DW_TAG_pointer_type, size: 64, align: 64, baseType: !"_ZTS1B")