Revert "Revert "DI: Fold constant arguments into a single MDString""

This reverts commit r218918, effectively reapplying r218914 after fixing
an Ocaml bindings test and an Asan crash.  The root cause of the latter
was a tightened-up check in `DILexicalBlock::Verify()`, so I'll file a
PR to investigate who requires the loose check (and why).

Original commit message follows.

--

This patch addresses the first stage of PR17891 by folding constant
arguments together into a single MDString.  Integers are stringified and
a `\0` character is used as a separator.

Part of PR17891.

Note: I've attached my testcases upgrade scripts to the PR.  If I've
just broken your out-of-tree testcases, they might help.

llvm-svn: 219010

1 files changed, 8 insertions, 8 deletions

diff --git a/llvm/test/DebugInfo/X86/multiple-aranges.ll b/llvm/test/DebugInfo/X86/multiple-aranges.ll
index 2da29387424..6d796dcef59 100644
--- a/llvm/test/DebugInfo/X86/multiple-aranges.ll
+++ b/llvm/test/DebugInfo/X86/multiple-aranges.ll
@@ -44,17 +44,17 @@ target triple = "x86_64-unknown-linux-gnu"
 !llvm.dbg.cu = !{!0, !7}
 !llvm.module.flags = !{!12, !13}
 
-!0 = metadata !{i32 786449, metadata !1, i32 12, metadata !"clang version 3.4 ", i1 false, metadata !"", i32 0, metadata !2, metadata !2, metadata !2, metadata !3, metadata !2, metadata !""} ; [ DW_TAG_compile_unit ] [/home/kayamon/test1.c] [DW_LANG_C99]
+!0 = metadata !{metadata !"0x11\0012\00clang version 3.4 \000\00\000\00\000", metadata !1, metadata !2, metadata !2, metadata !2, metadata !3, metadata !2} ; [ DW_TAG_compile_unit ] [/home/kayamon/test1.c] [DW_LANG_C99]
 !1 = metadata !{metadata !"test1.c", metadata !"/home/kayamon"}
 !2 = metadata !{}
 !3 = metadata !{metadata !4}
-!4 = metadata !{i32 786484, i32 0, null, metadata !"kittens", metadata !"kittens", metadata !"", metadata !5, i32 1, metadata !6, i32 0, i32 1, i32* @kittens, null} ; [ DW_TAG_variable ] [kittens] [line 1] [def]
-!5 = metadata !{i32 786473, metadata !1}          ; [ DW_TAG_file_type ] [/home/kayamon/test1.c]
-!6 = metadata !{i32 786468, null, null, metadata !"int", i32 0, i64 32, i64 32, i64 0, i32 0, i32 5} ; [ DW_TAG_base_type ] [int] [line 0, size 32, align 32, offset 0, enc DW_ATE_signed]
-!7 = metadata !{i32 786449, metadata !8, i32 12, metadata !"clang version 3.4 ", i1 false, metadata !"", i32 0, metadata !2, metadata !2, metadata !2, metadata !9, metadata !2, metadata !""} ; [ DW_TAG_compile_unit ] [/home/kayamon/test2.c] [DW_LANG_C99]
+!4 = metadata !{metadata !"0x34\00kittens\00kittens\00\001\000\001", null, metadata !5, metadata !6, i32* @kittens, null} ; [ DW_TAG_variable ] [kittens] [line 1] [def]
+!5 = metadata !{metadata !"0x29", metadata !1}          ; [ DW_TAG_file_type ] [/home/kayamon/test1.c]
+!6 = metadata !{metadata !"0x24\00int\000\0032\0032\000\000\005", null, null} ; [ DW_TAG_base_type ] [int] [line 0, size 32, align 32, offset 0, enc DW_ATE_signed]
+!7 = metadata !{metadata !"0x11\0012\00clang version 3.4 \000\00\000\00\000", metadata !8, metadata !2, metadata !2, metadata !2, metadata !9, metadata !2} ; [ DW_TAG_compile_unit ] [/home/kayamon/test2.c] [DW_LANG_C99]
 !8 = metadata !{metadata !"test2.c", metadata !"/home/kayamon"}
 !9 = metadata !{metadata !10}
-!10 = metadata !{i32 786484, i32 0, null, metadata !"rainbows", metadata !"rainbows", metadata !"", metadata !11, i32 1, metadata !6, i32 0, i32 1, i32* @rainbows, null} ; [ DW_TAG_variable ] [rainbows] [line 1] [def]
-!11 = metadata !{i32 786473, metadata !8}         ; [ DW_TAG_file_type ] [/home/kayamon/test2.c]
+!10 = metadata !{metadata !"0x34\00rainbows\00rainbows\00\001\000\001", null, metadata !11, metadata !6, i32* @rainbows, null} ; [ DW_TAG_variable ] [rainbows] [line 1] [def]
+!11 = metadata !{metadata !"0x29", metadata !8}         ; [ DW_TAG_file_type ] [/home/kayamon/test2.c]
 !12 = metadata !{i32 2, metadata !"Dwarf Version", i32 4}
-!13 = metadata !{i32 1, metadata !"Debug Info Version", i32 1}
+!13 = metadata !{i32 1, metadata !"Debug Info Version", i32 2}