Refactor filename/directory in DICompileUnit into a DIFile

This is the next step towards making the metadata for DIScopes have a common
prefix rather than having to delegate based on their tag type.

llvm-svn: 176913
diff --git a/llvm/test/CodeGen/X86/2010-05-25-DotDebugLoc.ll b/llvm/test/CodeGen/X86/2010-05-25-DotDebugLoc.ll
index 1553958..0c47cc9 100644
--- a/llvm/test/CodeGen/X86/2010-05-25-DotDebugLoc.ll
+++ b/llvm/test/CodeGen/X86/2010-05-25-DotDebugLoc.ll
@@ -205,7 +205,7 @@
 !0 = metadata !{i32 786689, metadata !1, metadata !"a", metadata !2, i32 1921, metadata !9, i32 0, null} ; [ DW_TAG_arg_variable ]
 !1 = metadata !{i32 786478, i32 0, metadata !2, metadata !"__divsc3", metadata !"__divsc3", metadata !"__divsc3", metadata !2, i32 1922, metadata !4, i1 false, i1 true, i32 0, i32 0, null, i1 false, i1 true, %0 (float, float, float, float)* @__divsc3, null, null, metadata !43, i32 1922} ; [ DW_TAG_subprogram ]
 !2 = metadata !{i32 786473, metadata !"libgcc2.c", metadata !"/Users/yash/clean/LG.D/gcc/../../llvmgcc/gcc", metadata !3} ; [ DW_TAG_file_type ]
-!3 = metadata !{i32 786449, i32 0, i32 1, metadata !"libgcc2.c", metadata !"/Users/yash/clean/LG.D/gcc/../../llvmgcc/gcc", metadata !"4.2.1 (Based on Apple Inc. build 5658) (LLVM build)", i1 true, metadata !"", i32 0, null, null, metadata !44, null, metadata !""} ; [ DW_TAG_compile_unit ]
+!3 = metadata !{i32 786449, i32 0, i32 1, metadata !2, metadata !"4.2.1 (Based on Apple Inc. build 5658) (LLVM build)", i1 true, metadata !"", i32 0, null, null, metadata !44, null, metadata !""} ; [ DW_TAG_compile_unit ]
 !4 = metadata !{i32 786453, metadata !2, metadata !"", metadata !2, i32 0, i64 0, i64 0, i64 0, i32 0, null, metadata !5, i32 0, null} ; [ DW_TAG_subroutine_type ]
 !5 = metadata !{metadata !6, metadata !9, metadata !9, metadata !9, metadata !9}
 !6 = metadata !{i32 786454, metadata !7, metadata !"SCtype", metadata !7, i32 170, i64 0, i64 0, i64 0, i32 0, metadata !8} ; [ DW_TAG_typedef ]