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.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219010 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 10 insertions, 9 deletions

diff --git a/test/Linker/2011-08-04-Metadata.ll b/test/Linker/2011-08-04-Metadata.ll
index cdf4f6f1436..7bdbb33fda5 100644
--- a/test/Linker/2011-08-04-Metadata.ll
+++ b/test/Linker/2011-08-04-Metadata.ll
@@ -2,7 +2,8 @@
 ; RUN: llvm-dis < %t.bc | FileCheck %s
 ; Test if internal global variable's debug info is merged appropriately or not.
 
-;CHECK:  metadata !{i32 589876, i32 0, metadata !{{[0-9]+}}, metadata !"x", metadata !"x", metadata !"", metadata !{{[0-9]+}}, i32 1, metadata !{{[0-9]+}}, i32 1, i32 1, i32* @x1}
+;CHECK:  metadata !{metadata !"0x34\00x\00x\00\002\001\001", metadata !{{[0-9]+}}, metadata !{{[0-9]+}}, metadata !{{[0-9]+}}, i32* @x}
+;CHECK:  metadata !{metadata !"0x34\00x\00x\00\001\001\001", metadata !{{[0-9]+}}, metadata !{{[0-9]+}}, metadata !{{[0-9]+}}, i32* @x1}
 target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64"
 target triple = "x86_64-apple-macosx10.7.0"
 
@@ -19,15 +20,15 @@ entry:
 !llvm.dbg.sp = !{!1}
 !llvm.dbg.gv = !{!5}
 
-!0 = metadata !{i32 589841, metadata !9, i32 12, metadata !"clang version 3.0 ()", i1 true, metadata !"", i32 0, metadata !4, metadata !4, metadata !10, null, null, metadata !""}
-!1 = metadata !{i32 589870, metadata !9, metadata !2, metadata !"foo", metadata !"foo", metadata !"", i32 3, metadata !3, i1 false, i1 true, i32 0, i32 0, null, i32 0, i1 false, void ()* @foo, null, null, null, i32 0} ; [ DW_TAG_subprogram ] [line 3] [def] [scope 0] [foo]
-!2 = metadata !{i32 589865, metadata !9}
-!3 = metadata !{i32 589845, metadata !9, metadata !2, metadata !"", i32 0, i64 0, i64 0, i32 0, i32 0, null, metadata !4, i32 0, null, null, null} ; [ DW_TAG_subroutine_type ] [line 0, size 0, align 0, offset 0] [from ]
+!0 = metadata !{metadata !"0x11\0012\00clang version 3.0 ()\001\00\000\00\000", metadata !9, metadata !4, metadata !4, metadata !10, null, null} ; [ DW_TAG_compile_unit ]
+!1 = metadata !{metadata !"0x2e\00foo\00foo\00\003\000\001\000\006\000\000\000", metadata !9, metadata !2, metadata !3, null, void ()* @foo, null, null, null} ; [ DW_TAG_subprogram ] [line 3] [def] [scope 0] [foo]
+!2 = metadata !{metadata !"0x29", metadata !9} ; [ DW_TAG_file_type ]
+!3 = metadata !{metadata !"0x15\00\000\000\000\000\000\000", metadata !9, metadata !2, null, metadata !4, null, null, null} ; [ DW_TAG_subroutine_type ] [line 0, size 0, align 0, offset 0] [from ]
 !4 = metadata !{null}
-!5 = metadata !{i32 589876, i32 0, metadata !0, metadata !"x", metadata !"x", metadata !"", metadata !2, i32 2, metadata !6, i32 1, i32 1, i32* @x}
-!6 = metadata !{i32 589860, null, metadata !0, metadata !"int", i32 0, i64 32, i64 32, i64 0, i32 0, i32 5}
+!5 = metadata !{metadata !"0x34\00x\00x\00\002\001\001", metadata !0, metadata !2, metadata !6, i32* @x} ; [ DW_TAG_variable ]
+!6 = metadata !{metadata !"0x24\00int\000\0032\0032\000\000\005", null, metadata !0} ; [ DW_TAG_base_type ]
 !7 = metadata !{i32 3, i32 14, metadata !8, null}
-!8 = metadata !{i32 589835, metadata !9, metadata !1, i32 3, i32 12, i32 0}
+!8 = metadata !{metadata !"0xb\003\0012\000", metadata !9, metadata !1} ; [ DW_TAG_lexical_block ]
 !9 = metadata !{metadata !"/tmp/one.c", metadata !"/Volumes/Lalgate/Slate/D"}
 !10 = metadata !{metadata !1}
-!11 = metadata !{i32 1, metadata !"Debug Info Version", i32 1}
+!11 = metadata !{i32 1, metadata !"Debug Info Version", i32 2}