Debug info: Unique types before emitting them to DWARF, where applicable.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@203983 91177308-0d34-0410-b5e6-96231b3b80d8

Author: adrian-prantl

lib/CodeGen/AsmPrinter/DwarfUnit.cpp

@@ -958,6 +958,9 @@ DIE *DwarfUnit::getOrCreateTypeDIE(const MDNode *TyNode) {
   DIE *ContextDIE = getOrCreateContextDIE(Context);
   assert(ContextDIE);
 
+  // Unique the type. This is a noop if the type has no unique identifier.
+  Ty = DIType(resolve(Ty.getRef()));
+
   DIE *TyDIE = getDIE(Ty);
   if (TyDIE)
     return TyDIE;

test/Linker/type-unique-odr-a.ll

@@ -28,6 +28,10 @@
 ; CHECK-NEXT:   DW_AT_MIPS_linkage_name {{.*}} "_ZL3barv"
 ; CHECK:      DW_TAG_class_type
 ; CHECK-NEXT:   DW_AT_name {{.*}} "A"
+; CHECK-NOT:  DW_TAG
+; CHECK:      DW_TAG_member
+; CHECK-NEXT:   DW_AT_name {{.*}} "data"
+; CHECK-NOT:  DW_TAG
 ; CHECK:      DW_TAG_subprogram
 ; CHECK-NEXT:   DW_AT_MIPS_linkage_name {{.*}} "_ZN1A6getFooEv"
 ; CHECK-NEXT:   DW_AT_name {{.*}} "getFoo"