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, 3 insertions, 3 deletions

diff --git a/llvm/test/Linker/replaced-function-matches-first-subprogram.ll b/llvm/test/Linker/replaced-function-matches-first-subprogram.ll
index fc7e653786e..1037f0a09a7 100644
--- a/llvm/test/Linker/replaced-function-matches-first-subprogram.ll
+++ b/llvm/test/Linker/replaced-function-matches-first-subprogram.ll
@@ -39,9 +39,9 @@ entry:
 !llvm.ident = !{!13}
 
 ; Extract out the list of subprograms from each compile unit.
-; CHECK-DAG: ![[CU1]] = !DICompileUnit({{.*}} subprograms: ![[SPs1:[0-9]+]]
-; CHECK-DAG: ![[CU2]] = !DICompileUnit({{.*}} subprograms: ![[SPs2:[0-9]+]]
-!0 = !DICompileUnit(language: DW_LANG_C_plus_plus, producer: "clang version 3.6.0 (trunk 224193) (llvm/trunk 224197)", isOptimized: false, emissionKind: 2, file: !1, enums: !2, retainedTypes: !2, subprograms: !3, globals: !2, imports: !2)
+; CHECK-DAG: ![[CU1]] = distinct !DICompileUnit({{.*}} subprograms: ![[SPs1:[0-9]+]]
+; CHECK-DAG: ![[CU2]] = distinct !DICompileUnit({{.*}} subprograms: ![[SPs2:[0-9]+]]
+!0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, producer: "clang version 3.6.0 (trunk 224193) (llvm/trunk 224197)", isOptimized: false, emissionKind: 2, file: !1, enums: !2, retainedTypes: !2, subprograms: !3, globals: !2, imports: !2)
 !1 = !DIFile(filename: "t1.cpp", directory: "/Users/dexonsmith/data/llvm/staging/test/Linker/repro/d1")
 !2 = !{}