Remove the (apparently) unnecessary debug info metadata indirection.

The main lists of debug info metadata attached to the compile_unit had an extra
layer of metadata nodes they went through for no apparent reason. This patch
removes that (& still passes just as much of the GDB 7.5 test suite). If anyone
can show evidence as to why these extra metadata nodes are there I'm open to
reverting this patch & documenting why they're there.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@174266 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/CodeGen/PowerPC/dbg.ll b/test/CodeGen/PowerPC/dbg.ll
index e161cb0..8d87cf7 100644
--- a/test/CodeGen/PowerPC/dbg.ll
+++ b/test/CodeGen/PowerPC/dbg.ll
@@ -17,10 +17,8 @@
 !llvm.dbg.cu = !{!0}
 
 !0 = metadata !{i32 720913, i32 0, i32 12, metadata !"dbg.c", metadata !"/src", metadata !"clang version 3.1", i1 true, i1 true, metadata !"", i32 0, metadata !1, metadata !1, metadata !3, metadata !1} ; [ DW_TAG_compile_unit ]
-!1 = metadata !{metadata !2}
-!2 = metadata !{i32 0}
-!3 = metadata !{metadata !4}
-!4 = metadata !{metadata !5}
+!1 = metadata !{i32 0}
+!3 = metadata !{metadata !5}
 !5 = metadata !{i32 720942, i32 0, metadata !6, metadata !"main", metadata !"main", metadata !"", metadata !6, i32 1, metadata !7, i1 false, i1 true, i32 0, i32 0, null, i32 256, i1 true, i32 (i32, i8**)* @main, null, null, metadata !13} ; [ DW_TAG_subprogram ]
 !6 = metadata !{i32 720937, metadata !"dbg.c", metadata !"/src", null} ; [ DW_TAG_file_type ]
 !7 = metadata !{i32 720917, i32 0, metadata !"", i32 0, i32 0, i64 0, i64 0, i64 0, i32 0, null, metadata !8, i32 0, i32 0} ; [ DW_TAG_subroutine_type ]
diff --git a/test/CodeGen/X86/dbg-declare.ll b/test/CodeGen/X86/dbg-declare.ll
index b73e310..9d13de1 100644
--- a/test/CodeGen/X86/dbg-declare.ll
+++ b/test/CodeGen/X86/dbg-declare.ll
@@ -30,10 +30,8 @@
 !llvm.dbg.cu = !{!0}
 
 !0 = metadata !{i32 786449, i32 0, i32 12, metadata !"20020104-2.c", metadata !"/Volumes/Sandbox/llvm", metadata !"clang version 3.1 (trunk 153698)", i1 true, i1 false, metadata !"", i32 0, metadata !1, metadata !1, metadata !3, metadata !1} ; [ DW_TAG_compile_unit ]
-!1 = metadata !{metadata !2}
-!2 = metadata !{i32 0}
-!3 = metadata !{metadata !4}
-!4 = metadata !{metadata !5}
+!1 = metadata !{i32 0}
+!3 = metadata !{metadata !5}
 !5 = metadata !{i32 786478, i32 0, metadata !6, metadata !"foo", metadata !"foo", metadata !"", metadata !6, i32 6, metadata !7, i1 false, i1 true, i32 0, i32 0, null, i32 256, i1 false, i32 (i32*)* @foo, null, null, metadata !12} ; [ DW_TAG_subprogram ]
 !6 = metadata !{i32 786473, metadata !"20020104-2.c", metadata !"/Volumes/Sandbox/llvm", null} ; [ DW_TAG_file_type ]
 !7 = metadata !{i32 786453, i32 0, metadata !"", i32 0, i32 0, i64 0, i64 0, i64 0, i32 0, null, metadata !8, i32 0, i32 0} ; [ DW_TAG_subroutine_type ]
diff --git a/test/CodeGen/X86/dbg-subrange.ll b/test/CodeGen/X86/dbg-subrange.ll
index 0efb50e..c9be972 100644
--- a/test/CodeGen/X86/dbg-subrange.ll
+++ b/test/CodeGen/X86/dbg-subrange.ll
@@ -15,18 +15,15 @@
 !llvm.dbg.cu = !{!0}
 
 !0 = metadata !{i32 720913, i32 0, i32 12, metadata !"small.c", metadata !"/private/tmp", metadata !"clang version 3.1 (trunk 144833)", i1 true, i1 false, metadata !"", i32 0, metadata !1, metadata !1, metadata !3, metadata !11} ; [ DW_TAG_compile_unit ]
-!1 = metadata !{metadata !2}
-!2 = metadata !{i32 0}
-!3 = metadata !{metadata !4}
-!4 = metadata !{metadata !5}
+!1 = metadata !{i32 0}
+!3 = metadata !{metadata !5}
 !5 = metadata !{i32 720942, i32 0, metadata !6, metadata !"bar", metadata !"bar", metadata !"", metadata !6, i32 4, metadata !7, i1 false, i1 true, i32 0, i32 0, i32 0, i32 256, i1 false, void ()* @bar, null, null, metadata !9} ; [ DW_TAG_subprogram ]
 !6 = metadata !{i32 720937, metadata !"small.c", metadata !"/private/tmp", null} ; [ DW_TAG_file_type ]
 !7 = metadata !{i32 720917, i32 0, metadata !"", i32 0, i32 0, i64 0, i64 0, i32 0, i32 0, i32 0, metadata !8, i32 0, i32 0} ; [ DW_TAG_subroutine_type ]
 !8 = metadata !{null}
 !9 = metadata !{metadata !10}
 !10 = metadata !{i32 720932}                      ; [ DW_TAG_base_type ]
-!11 = metadata !{metadata !12}
-!12 = metadata !{metadata !13}
+!11 = metadata !{metadata !13}
 !13 = metadata !{i32 720948, i32 0, null, metadata !"s", metadata !"s", metadata !"", metadata !6, i32 2, metadata !14, i32 0, i32 1, [4294967296 x i8]* @s} ; [ DW_TAG_variable ]
 !14 = metadata !{i32 720897, null, metadata !"", null, i32 0, i64 34359738368, i64 8, i32 0, i32 0, metadata !15, metadata !16, i32 0, i32 0} ; [ DW_TAG_array_type ]
 !15 = metadata !{i32 720932, null, metadata !"char", null, i32 0, i64 8, i64 8, i64 0, i32 0, i32 6} ; [ DW_TAG_base_type ]