Debug info: refactor the first field of DICompileUnit to be a raw file/directory pair

This removes the DICompileUnit special case from DIScope.

llvm-svn: 177610
diff --git a/llvm/test/DebugInfo/AArch64/dwarfdump.ll b/llvm/test/DebugInfo/AArch64/dwarfdump.ll
index 440b791..24ab2f9 100644
--- a/llvm/test/DebugInfo/AArch64/dwarfdump.ll
+++ b/llvm/test/DebugInfo/AArch64/dwarfdump.ll
@@ -22,7 +22,7 @@
 
 !llvm.dbg.cu = !{!0}
 
-!0 = metadata !{i32 786449, metadata !4, i32 12, metadata !"clang version 3.3 ", i1 false, metadata !"", i32 0, metadata !1, metadata !1, metadata !2, metadata !1, metadata !""} ; [ DW_TAG_compile_unit ] [/home/timnor01/llvm/build/tmp.c] [DW_LANG_C99]
+!0 = metadata !{i32 786449, metadata !9, i32 12, metadata !"clang version 3.3 ", i1 false, metadata !"", i32 0, metadata !1, metadata !1, metadata !2, metadata !1, metadata !""} ; [ DW_TAG_compile_unit ] [/home/timnor01/llvm/build/tmp.c] [DW_LANG_C99]
 !1 = metadata !{i32 0}
 !2 = metadata !{metadata !3}
 !3 = metadata !{i32 786478, i32 0, metadata !4, metadata !"main", metadata !"main", metadata !"", metadata !4, i32 1, metadata !5, i1 false, i1 true, i32 0, i32 0, null, i32 0, i1 false, i32 ()* @main, null, null, metadata !1, i32 1} ; [ DW_TAG_subprogram ] [line 1] [def] [main]
diff --git a/llvm/test/DebugInfo/AArch64/variable-loc.ll b/llvm/test/DebugInfo/AArch64/variable-loc.ll
index abafb2a..db54f9a 100644
--- a/llvm/test/DebugInfo/AArch64/variable-loc.ll
+++ b/llvm/test/DebugInfo/AArch64/variable-loc.ll
@@ -69,7 +69,7 @@
 
 !llvm.dbg.cu = !{!0}
 
-!0 = metadata !{i32 786449, metadata !6, i32 12, metadata !"clang version 3.2 ", i1 false, metadata !"", i32 0, metadata !1, metadata !1, metadata !3, metadata !1, metadata !""} ; [ DW_TAG_compile_unit ] [/home/timnor01/a64-trunk/build/simple.c] [DW_LANG_C99]
+!0 = metadata !{i32 786449, metadata !29, i32 12, metadata !"clang version 3.2 ", i1 false, metadata !"", i32 0, metadata !1, metadata !1, metadata !3, metadata !1, metadata !""} ; [ DW_TAG_compile_unit ] [/home/timnor01/a64-trunk/build/simple.c] [DW_LANG_C99]
 !1 = metadata !{i32 0}
 !3 = metadata !{metadata !5, metadata !11, metadata !14}
 !5 = metadata !{i32 786478, i32 0, metadata !6, metadata !"populate_array", metadata !"populate_array", metadata !"", metadata !6, i32 4, metadata !7, i1 false, i1 true, i32 0, i32 0, null, i32 256, i1 false, void (i32*, i32)* @populate_array, null, null, metadata !1, i32 4} ; [ DW_TAG_subprogram ] [line 4] [def] [populate_array]