DI: Disallow uniquable DICompileUnits

Since r241097, `DIBuilder` has only created distinct `DICompileUnit`s.
The backend is liable to start relying on that (if it hasn't already),
so make uniquable `DICompileUnit`s illegal and automatically upgrade old
bitcode.  This is a nice cleanup, since we can remove an unnecessary
`DenseSet` (and the associated uniquing info) from `LLVMContextImpl`.

Almost all the testcases were updated with this script:

    git grep -e '= !DICompileUnit' -l -- test |
    grep -v test/Bitcode |
    xargs sed -i '' -e 's,= !DICompileUnit,= distinct !DICompileUnit,'

I imagine something similar should work for out-of-tree testcases.

llvm-svn: 243885

1 files changed, 1 insertions, 1 deletions

diff --git a/llvm/test/CodeGen/ARM/debug-info-arg.ll b/llvm/test/CodeGen/ARM/debug-info-arg.ll
index fcea788a132..146a532b7c9 100644
--- a/llvm/test/CodeGen/ARM/debug-info-arg.ll
+++ b/llvm/test/CodeGen/ARM/debug-info-arg.ll
@@ -32,7 +32,7 @@ declare void @llvm.dbg.value(metadata, i64, metadata, metadata) nounwind readnon
 !llvm.dbg.cu = !{!0}
 !llvm.module.flags = !{!33}
 
-!0 = !DICompileUnit(language: DW_LANG_C99, producer: "Apple clang version 3.0 (tags/Apple/clang-211.10.1) (based on LLVM 3.0svn)", isOptimized: true, emissionKind: 1, file: !32, enums: !{}, retainedTypes: !{}, subprograms: !30, imports:  null)
+!0 = distinct !DICompileUnit(language: DW_LANG_C99, producer: "Apple clang version 3.0 (tags/Apple/clang-211.10.1) (based on LLVM 3.0svn)", isOptimized: true, emissionKind: 1, file: !32, enums: !{}, retainedTypes: !{}, subprograms: !30, imports:  null)
 !1 = !DISubprogram(name: "foo", line: 11, isLocal: false, isDefinition: true, virtualIndex: 6, flags: DIFlagPrototyped, isOptimized: true, scopeLine: 11, file: !2, scope: !2, type: !3, function: void (%struct.tag_s*, %struct.tag_s*, i64, i64, %struct.tag_s*, %struct.tag_s*)* @foo, variables: !31)
 !2 = !DIFile(filename: "one.c", directory: "/Volumes/Athwagate/R10048772")
 !3 = !DISubroutineType(types: !4)