Refactor the DIFile (2nd) parameter to DITypes to be an MDNode reference to a raw directory/file pair

This makes DIType's first non-tag parameter the same as DIFile's, allowing them
to both share the common implementation of getFilename/getDirectory in DIScope.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177467 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/DebugInfo/X86/empty-and-one-elem-array.ll b/test/DebugInfo/X86/empty-and-one-elem-array.ll
index 0ad375f..c5fe575 100644
--- a/test/DebugInfo/X86/empty-and-one-elem-array.ll
+++ b/test/DebugInfo/X86/empty-and-one-elem-array.ll
@@ -69,19 +69,19 @@
 !9 = 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]
 !10 = metadata !{i32 786688, metadata !11, metadata !"my_foo", metadata !6, i32 12, metadata !12, i32 0, i32 0} ; [ DW_TAG_auto_variable ] [my_foo] [line 12]
 !11 = metadata !{i32 786443, metadata !5, i32 11, i32 0, metadata !6, i32 0} ; [ DW_TAG_lexical_block ] [/Volumes/Sandbox/llvm/test.c]
-!12 = metadata !{i32 786451, metadata !6, null, metadata !"foo", i32 1, i64 64, i64 32, i32 0, i32 0, null, metadata !13, i32 0, i32 0, i32 0} ; [ DW_TAG_structure_type ] [foo] [line 1, size 64, align 32, offset 0] [from ]
+!12 = metadata !{i32 786451, metadata !32, null, metadata !"foo", i32 1, i64 64, i64 32, i32 0, i32 0, null, metadata !13, i32 0, i32 0, i32 0} ; [ DW_TAG_structure_type ] [foo] [line 1, size 64, align 32, offset 0] [from ]
 !13 = metadata !{metadata !14, metadata !15}
-!14 = metadata !{i32 786445, metadata !6, metadata !12, metadata !"a", i32 2, i64 32, i64 32, i64 0, i32 0, metadata !9} ; [ DW_TAG_member ] [a] [line 2, size 32, align 32, offset 0] [from int]
-!15 = metadata !{i32 786445, metadata !6, metadata !12, metadata !"b", i32 3, i64 32, i64 32, i64 32, i32 0, metadata !16} ; [ DW_TAG_member ] [b] [line 3, size 32, align 32, offset 32] [from ]
+!14 = metadata !{i32 786445, metadata !32, metadata !12, metadata !"a", i32 2, i64 32, i64 32, i64 0, i32 0, metadata !9} ; [ DW_TAG_member ] [a] [line 2, size 32, align 32, offset 0] [from int]
+!15 = metadata !{i32 786445, metadata !32, metadata !12, metadata !"b", i32 3, i64 32, i64 32, i64 32, i32 0, metadata !16} ; [ DW_TAG_member ] [b] [line 3, size 32, align 32, offset 32] [from ]
 !16 = metadata !{i32 786433, null, null, metadata !"", i32 0, i64 32, i64 32, i32 0, i32 0, metadata !9, metadata !17, i32 0, i32 0} ; [ DW_TAG_array_type ] [line 0, size 32, align 32, offset 0] [from int]
 !17 = metadata !{metadata !18}
 !18 = metadata !{i32 786465, i64 0, i64 1} ; [ DW_TAG_subrange_type ] [0, 1]
 !19 = metadata !{i32 12, i32 0, metadata !11, null}
 !20 = metadata !{i32 786688, metadata !11, metadata !"my_bar", metadata !6, i32 13, metadata !21, i32 0, i32 0} ; [ DW_TAG_auto_variable ] [my_bar] [line 13]
-!21 = metadata !{i32 786451, metadata !6, null, metadata !"bar", i32 6, i64 32, i64 32, i32 0, i32 0, null, metadata !22, i32 0, i32 0, i32 0} ; [ DW_TAG_structure_type ] [bar] [line 6, size 32, align 32, offset 0] [from ]
+!21 = metadata !{i32 786451, metadata !32, null, metadata !"bar", i32 6, i64 32, i64 32, i32 0, i32 0, null, metadata !22, i32 0, i32 0, i32 0} ; [ DW_TAG_structure_type ] [bar] [line 6, size 32, align 32, offset 0] [from ]
 !22 = metadata !{metadata !23, metadata !24}
-!23 = metadata !{i32 786445, metadata !6, metadata !21, metadata !"a", i32 7, i64 32, i64 32, i64 0, i32 0, metadata !9} ; [ DW_TAG_member ] [a] [line 7, size 32, align 32, offset 0] [from int]
-!24 = metadata !{i32 786445, metadata !6, metadata !21, metadata !"b", i32 8, i64 0, i64 32, i64 32, i32 0, metadata !25} ; [ DW_TAG_member ] [b] [line 8, size 0, align 32, offset 32] [from ]
+!23 = metadata !{i32 786445, metadata !32, metadata !21, metadata !"a", i32 7, i64 32, i64 32, i64 0, i32 0, metadata !9} ; [ DW_TAG_member ] [a] [line 7, size 32, align 32, offset 0] [from int]
+!24 = metadata !{i32 786445, metadata !32, metadata !21, metadata !"b", i32 8, i64 0, i64 32, i64 32, i32 0, metadata !25} ; [ DW_TAG_member ] [b] [line 8, size 0, align 32, offset 32] [from ]
 !25 = metadata !{i32 786433, null, null, metadata !"", i32 0, i64 0, i64 32, i32 0, i32 0, metadata !9, metadata !26, i32 0, i32 0} ; [ DW_TAG_array_type ] [line 0, size 0, align 32, offset 0] [from int]
 !26 = metadata !{metadata !27}
 !27 = metadata !{i32 786465, i64 0, i64 0} ; [ DW_TAG_subrange_type ] [0, 0]