Remove the DW_AT_MIPS_linkage name attribute when we don't need it

output (we're emitting a specification already and the information
isn't changing) and we're not in old gdb compat mode.

Saves 1% on the debug information for a build of llvm.

Fixes rdar://11043421

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@162493 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 59 insertions, 4 deletions

diff --git a/test/DebugInfo/X86/concrete_out_of_line.ll b/test/DebugInfo/X86/concrete_out_of_line.ll
index a22707189b..0f02271f97 100644
--- a/test/DebugInfo/X86/concrete_out_of_line.ll
+++ b/test/DebugInfo/X86/concrete_out_of_line.ll
@@ -7,16 +7,15 @@
 ; first check that we have a TAG_subprogram at a given offset and it has
 ; AT_inline.
 
-; CHECK: 0x00000134:   DW_TAG_subprogram [18]
-; CHECK-NEXT:     DW_AT_MIPS_linkage_name
+; CHECK: 0x00000130:   DW_TAG_subprogram [18]
 ; CHECK-NEXT:     DW_AT_specification
 ; CHECK-NEXT:     DW_AT_inline
 
 
 ; and then that a TAG_subprogram refers to it with AT_abstract_origin.
 
-; CHECK: 0x00000184:   DW_TAG_subprogram [20]
-; CHECK-NEXT: DW_AT_abstract_origin [DW_FORM_ref4]    (cu + 0x0134 => {0x00000134})
+; CHECK: 0x00000174:   DW_TAG_subprogram [20]
+; CHECK-NEXT: DW_AT_abstract_origin [DW_FORM_ref4]    (cu + 0x0130 => {0x00000130})
 
 define i32 @_ZN17nsAutoRefCnt7ReleaseEv() {
 entry:
diff --git a/test/DebugInfo/linkage-name.ll b/test/DebugInfo/linkage-name.ll
new file mode 100644
index 0000000000..b98492383a
--- /dev/null
+++ b/test/DebugInfo/linkage-name.ll
@@ -0,0 +1,56 @@
+; RUN: llc -mtriple=x86_64-macosx -darwin-gdb-compat=Disable %s -o %t -filetype=obj
+; RUN: llvm-dwarfdump %t | FileCheck %s
+
+; CHECK: DW_TAG_subprogram [9] *
+; CHECK-NOT: DW_AT_MIPS_linkage_name
+; CHECK: DW_AT_specification
+
+%class.A = type { i8 }
+
+@a = global %class.A zeroinitializer, align 1
+
+define i32 @_ZN1A1aEi(%class.A* %this, i32 %b) nounwind uwtable ssp align 2 {
+entry:
+  %this.addr = alloca %class.A*, align 8
+  %b.addr = alloca i32, align 4
+  store %class.A* %this, %class.A** %this.addr, align 8
+  call void @llvm.dbg.declare(metadata !{%class.A** %this.addr}, metadata !21), !dbg !23
+  store i32 %b, i32* %b.addr, align 4
+  call void @llvm.dbg.declare(metadata !{i32* %b.addr}, metadata !24), !dbg !25
+  %this1 = load %class.A** %this.addr
+  %0 = load i32* %b.addr, align 4, !dbg !26
+  ret i32 %0, !dbg !26
+}
+
+declare void @llvm.dbg.declare(metadata, metadata) nounwind readnone
+
+!llvm.dbg.cu = !{!0}
+
+!0 = metadata !{i32 786449, i32 0, i32 4, metadata !"foo.cpp", metadata !"/Users/echristo", metadata !"clang version 3.1 (trunk 152691) (llvm/trunk 152692)", i1 true, i1 false, metadata !"", i32 0, metadata !1, metadata !1, metadata !3, metadata !18} ; [ DW_TAG_compile_unit ]
+!1 = metadata !{metadata !2}
+!2 = metadata !{i32 0}
+!3 = metadata !{metadata !4}
+!4 = metadata !{metadata !5}
+!5 = metadata !{i32 786478, i32 0, null, metadata !"a", metadata !"a", metadata !"_ZN1A1aEi", metadata !6, i32 5, metadata !7, i1 false, i1 true, i32 0, i32 0, null, i32 256, i1 false, i32 (%class.A*, i32)* @_ZN1A1aEi, null, metadata !13, metadata !16} ; [ DW_TAG_subprogram ]
+!6 = metadata !{i32 786473, metadata !"foo.cpp", metadata !"/Users/echristo", 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 ]
+!8 = metadata !{metadata !9, metadata !10, metadata !9}
+!9 = metadata !{i32 786468, null, metadata !"int", null, i32 0, i64 32, i64 32, i64 0, i32 0, i32 5} ; [ DW_TAG_base_type ]
+!10 = metadata !{i32 786447, i32 0, metadata !"", i32 0, i32 0, i64 64, i64 64, i64 0, i32 64, metadata !11} ; [ DW_TAG_pointer_type ]
+!11 = metadata !{i32 786434, null, metadata !"A", metadata !6, i32 1, i64 8, i64 8, i32 0, i32 0, null, metadata !12, i32 0, null, null} ; [ DW_TAG_class_type ]
+!12 = metadata !{metadata !13}
+!13 = metadata !{i32 786478, i32 0, metadata !11, metadata !"a", metadata !"a", metadata !"_ZN1A1aEi", metadata !6, i32 2, metadata !7, i1 false, i1 false, i32 0, i32 0, null, i32 257, i1 false, null, null, i32 0, metadata !14} ; [ DW_TAG_subprogram ]
+!14 = metadata !{metadata !15}
+!15 = metadata !{i32 786468}                      ; [ DW_TAG_base_type ]
+!16 = metadata !{metadata !17}
+!17 = metadata !{i32 786468}                      ; [ DW_TAG_base_type ]
+!18 = metadata !{metadata !19}
+!19 = metadata !{metadata !20}
+!20 = metadata !{i32 786484, i32 0, null, metadata !"a", metadata !"a", metadata !"", metadata !6, i32 9, metadata !11, i32 0, i32 1, %class.A* @a} ; [ DW_TAG_variable ]
+!21 = metadata !{i32 786689, metadata !5, metadata !"this", metadata !6, i32 16777221, metadata !22, i32 64, i32 0} ; [ DW_TAG_arg_variable ]
+!22 = metadata !{i32 786447, null, metadata !"", null, i32 0, i64 64, i64 64, i64 0, i32 0, metadata !11} ; [ DW_TAG_pointer_type ]
+!23 = metadata !{i32 5, i32 8, metadata !5, null}
+!24 = metadata !{i32 786689, metadata !5, metadata !"b", metadata !6, i32 33554437, metadata !9, i32 0, i32 0} ; [ DW_TAG_arg_variable ]
+!25 = metadata !{i32 5, i32 14, metadata !5, null}
+!26 = metadata !{i32 6, i32 4, metadata !27, null}
+!27 = metadata !{i32 786443, metadata !5, i32 5, i32 17, metadata !6, i32 0} ; [ DW_TAG_lexical_block ]