llvm-6502/test/DebugInfo/PR20038.ll
David Blaikie e2cf6dc5c9 DebugInfo: Elide lexical scopes which only contain other (inline or lexical) scopes.
DW_TAG_lexical_scopes inform debuggers about the instruction range for
which a given variable (or imported declaration/module/etc) is valid. If
the scope doesn't itself contain any such entities, it's a waste of
space and should be omitted.

We were correctly doing this for entirely empty leaves, but not for
intermediate nodes.

Reduces total (not just debug sections) .o file size for a bootstrap
-gmlt LLVM by 22% and bootstrap -gmlt clang executable by 13%. The wins
for a full -g build will be less as a % (and in absolute terms), but
should still be substantial - with some of that win being fewer
relocations, thus more substantiall reducing link times than fewer bytes
alone would have.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@216861 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-31 21:26:22 +00:00

165 lines
9.2 KiB
LLVM

; REQUIRES: object-emission
; RUN: %llc_dwarf -O0 -filetype=obj < %s | llvm-dwarfdump -debug-dump=info - | FileCheck %s
; IR generated from clang -O0 with:
; struct C {
; ~C();
; };
; extern bool b;
; void fun4() { b && (C(), 1); }
; __attribute__((always_inline)) C::~C() { }
; CHECK: DW_TAG_structure_type
; CHECK-NOT: DW_TAG
; CHECK: DW_AT_name {{.*}} "C"
; CHECK-NOT: {{DW_TAG|NULL}}
; CHECK: [[C_DTOR_DECL:.*]]: DW_TAG_subprogram
; CHECK-NOT: DW_TAG
; CHECK: DW_AT_name {{.*}} "~C"
; CHECK: [[D1_ABS:.*]]: DW_TAG_subprogram
; CHECK-NOT: DW_TAG
; CHECK: DW_AT_MIPS_linkage_name {{.*}} "_ZN1CD1Ev"
; CHECK-NOT: {{DW_TAG|NULL}}
; CHECK: [[D1_THIS_ABS:.*]]: DW_TAG_formal_parameter
; CHECK-NOT: DW_TAG
; CHECK: DW_AT_name {{.*}} "this"
; CHECK: DW_TAG_subprogram
; CHECK-NOT: DW_TAG
; CHECK: DW_AT_name {{.*}} "fun4"
; CHECK-NOT: {{DW_TAG|NULL}}
; CHECK: DW_TAG_inlined_subroutine
; CHECK-NOT: DW_TAG
; CHECK: DW_AT_abstract_origin {{.*}} {[[D1_ABS]]}
; CHECK-NOT: {{DW_TAG|NULL}}
; CHECK: DW_TAG_formal_parameter
; CHECK-NOT: DW_TAG
; CHECK: DW_AT_abstract_origin {{.*}} {[[D1_THIS_ABS]]}
; FIXME: D2 is actually inlined into D1 but doesn't show up here, possibly due
; to there being no work in D2 (calling another member function from the dtor
; causes D2 to show up, calling a free function doesn't).
; CHECK-NOT: DW_TAG
; CHECK: NULL
; CHECK-NOT: DW_TAG
; CHECK: NULL
%struct.C = type { i8 }
@b = external global i8
; Function Attrs: nounwind
define void @_Z4fun4v() #0 {
entry:
%this.addr.i.i = alloca %struct.C*, align 8, !dbg !21
%this.addr.i = alloca %struct.C*, align 8, !dbg !22
%agg.tmp.ensured = alloca %struct.C, align 1
%cleanup.cond = alloca i1
%0 = load i8* @b, align 1, !dbg !24
%tobool = trunc i8 %0 to i1, !dbg !24
store i1 false, i1* %cleanup.cond
br i1 %tobool, label %land.rhs, label %land.end, !dbg !24
land.rhs: ; preds = %entry
store i1 true, i1* %cleanup.cond, !dbg !25
br label %land.end
land.end: ; preds = %land.rhs, %entry
%1 = phi i1 [ false, %entry ], [ true, %land.rhs ]
%cleanup.is_active = load i1* %cleanup.cond, !dbg !27
br i1 %cleanup.is_active, label %cleanup.action, label %cleanup.done, !dbg !27
cleanup.action: ; preds = %land.end
store %struct.C* %agg.tmp.ensured, %struct.C** %this.addr.i, align 8, !dbg !22
call void @llvm.dbg.declare(metadata !{%struct.C** %this.addr.i}, metadata !29), !dbg !31
%this1.i = load %struct.C** %this.addr.i, !dbg !22
store %struct.C* %this1.i, %struct.C** %this.addr.i.i, align 8, !dbg !21
call void @llvm.dbg.declare(metadata !{%struct.C** %this.addr.i.i}, metadata !32), !dbg !33
%this1.i.i = load %struct.C** %this.addr.i.i, !dbg !21
br label %cleanup.done, !dbg !22
cleanup.done: ; preds = %cleanup.action, %land.end
ret void, !dbg !34
}
; Function Attrs: alwaysinline nounwind
define void @_ZN1CD1Ev(%struct.C* %this) unnamed_addr #1 align 2 {
entry:
%this.addr.i = alloca %struct.C*, align 8, !dbg !37
%this.addr = alloca %struct.C*, align 8
store %struct.C* %this, %struct.C** %this.addr, align 8
call void @llvm.dbg.declare(metadata !{%struct.C** %this.addr}, metadata !29), !dbg !38
%this1 = load %struct.C** %this.addr
store %struct.C* %this1, %struct.C** %this.addr.i, align 8, !dbg !37
call void @llvm.dbg.declare(metadata !{%struct.C** %this.addr.i}, metadata !32), !dbg !39
%this1.i = load %struct.C** %this.addr.i, !dbg !37
ret void, !dbg !37
}
; Function Attrs: alwaysinline nounwind
define void @_ZN1CD2Ev(%struct.C* %this) unnamed_addr #1 align 2 {
entry:
%this.addr = alloca %struct.C*, align 8
store %struct.C* %this, %struct.C** %this.addr, align 8
call void @llvm.dbg.declare(metadata !{%struct.C** %this.addr}, metadata !32), !dbg !40
%this1 = load %struct.C** %this.addr
ret void, !dbg !41
}
; Function Attrs: nounwind readnone
declare void @llvm.dbg.declare(metadata, metadata) #2
attributes #0 = { nounwind "less-precise-fpmad"="false" "no-frame-pointer-elim"="false" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "no-realign-stack" "stack-protector-buffer-size"="8" "unsafe-fp-math"="false" "use-soft-float"="false" }
attributes #1 = { alwaysinline nounwind "less-precise-fpmad"="false" "no-frame-pointer-elim"="false" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "no-realign-stack" "stack-protector-buffer-size"="8" "unsafe-fp-math"="false" "use-soft-float"="false" }
attributes #2 = { nounwind readnone }
!llvm.dbg.cu = !{!0}
!llvm.module.flags = !{!18, !19}
!llvm.ident = !{!20}
!0 = metadata !{i32 786449, metadata !1, i32 4, metadata !"clang version 3.5.0 ", i1 false, metadata !"", i32 0, metadata !2, metadata !3, metadata !11, metadata !2, metadata !2, metadata !"", i32 1} ; [ DW_TAG_compile_unit ] [/tmp/dbginfo/<stdin>] [DW_LANG_C_plus_plus]
!1 = metadata !{metadata !"<stdin>", metadata !"/tmp/dbginfo"}
!2 = metadata !{}
!3 = metadata !{metadata !4}
!4 = metadata !{i32 786451, metadata !5, null, metadata !"C", i32 1, i64 8, i64 8, i32 0, i32 0, null, metadata !6, i32 0, null, null, metadata !"_ZTS1C"} ; [ DW_TAG_structure_type ] [C] [line 1, size 8, align 8, offset 0] [def] [from ]
!5 = metadata !{metadata !"PR20038.cpp", metadata !"/tmp/dbginfo"}
!6 = metadata !{metadata !7}
!7 = metadata !{i32 786478, metadata !5, metadata !"_ZTS1C", metadata !"~C", metadata !"~C", metadata !"", i32 2, metadata !8, i1 false, i1 false, i32 0, i32 0, null, i32 256, i1 false, null, null, i32 0, null, i32 2} ; [ DW_TAG_subprogram ] [line 2] [~C]
!8 = metadata !{i32 786453, i32 0, null, metadata !"", i32 0, i64 0, i64 0, i64 0, i32 0, null, metadata !9, i32 0, null, null, null} ; [ DW_TAG_subroutine_type ] [line 0, size 0, align 0, offset 0] [from ]
!9 = metadata !{null, metadata !10}
!10 = metadata !{i32 786447, null, null, metadata !"", i32 0, i64 64, i64 64, i64 0, i32 1088, metadata !"_ZTS1C"} ; [ DW_TAG_pointer_type ] [line 0, size 64, align 64, offset 0] [artificial] [from _ZTS1C]
!11 = metadata !{metadata !12, metadata !16, metadata !17}
!12 = metadata !{i32 786478, metadata !5, metadata !13, metadata !"fun4", metadata !"fun4", metadata !"_Z4fun4v", i32 5, metadata !14, i1 false, i1 true, i32 0, i32 0, null, i32 256, i1 false, void ()* @_Z4fun4v, null, null, metadata !2, i32 5} ; [ DW_TAG_subprogram ] [line 5] [def] [fun4]
!13 = metadata !{i32 786473, metadata !5} ; [ DW_TAG_file_type ] [/tmp/dbginfo/PR20038.cpp]
!14 = metadata !{i32 786453, i32 0, null, metadata !"", i32 0, i64 0, i64 0, i64 0, i32 0, null, metadata !15, i32 0, null, null, null} ; [ DW_TAG_subroutine_type ] [line 0, size 0, align 0, offset 0] [from ]
!15 = metadata !{null}
!16 = metadata !{i32 786478, metadata !5, metadata !"_ZTS1C", metadata !"~C", metadata !"~C", metadata !"_ZN1CD2Ev", i32 6, metadata !8, i1 false, i1 true, i32 0, i32 0, null, i32 256, i1 false, void (%struct.C*)* @_ZN1CD2Ev, null, metadata !7, metadata !2, i32 6} ; [ DW_TAG_subprogram ] [line 6] [def] [~C]
!17 = metadata !{i32 786478, metadata !5, metadata !"_ZTS1C", metadata !"~C", metadata !"~C", metadata !"_ZN1CD1Ev", i32 6, metadata !8, i1 false, i1 true, i32 0, i32 0, null, i32 256, i1 false, void (%struct.C*)* @_ZN1CD1Ev, null, metadata !7, metadata !2, i32 6} ; [ DW_TAG_subprogram ] [line 6] [def] [~C]
!18 = metadata !{i32 2, metadata !"Dwarf Version", i32 4}
!19 = metadata !{i32 2, metadata !"Debug Info Version", i32 1}
!20 = metadata !{metadata !"clang version 3.5.0 "}
!21 = metadata !{i32 6, i32 0, metadata !17, metadata !22}
!22 = metadata !{i32 5, i32 0, metadata !23, null}
!23 = metadata !{i32 786443, metadata !5, metadata !12, i32 5, i32 0, i32 3, i32 3} ; [ DW_TAG_lexical_block ] [/tmp/dbginfo/PR20038.cpp]
!24 = metadata !{i32 5, i32 0, metadata !12, null}
!25 = metadata !{i32 5, i32 0, metadata !26, null}
!26 = metadata !{i32 786443, metadata !5, metadata !12, i32 5, i32 0, i32 1, i32 1} ; [ DW_TAG_lexical_block ] [/tmp/dbginfo/PR20038.cpp]
!27 = metadata !{i32 5, i32 0, metadata !28, null}
!28 = metadata !{i32 786443, metadata !5, metadata !12, i32 5, i32 0, i32 2, i32 2} ; [ DW_TAG_lexical_block ] [/tmp/dbginfo/PR20038.cpp]
!29 = metadata !{i32 786689, metadata !17, metadata !"this", null, i32 16777216, metadata !30, i32 1088, i32 0} ; [ DW_TAG_arg_variable ] [this] [line 0]
!30 = metadata !{i32 786447, null, null, metadata !"", i32 0, i64 64, i64 64, i64 0, i32 0, metadata !"_ZTS1C"} ; [ DW_TAG_pointer_type ] [line 0, size 64, align 64, offset 0] [from _ZTS1C]
!31 = metadata !{i32 0, i32 0, metadata !17, metadata !22}
!32 = metadata !{i32 786689, metadata !16, metadata !"this", null, i32 16777216, metadata !30, i32 1088, i32 0} ; [ DW_TAG_arg_variable ] [this] [line 0]
!33 = metadata !{i32 0, i32 0, metadata !16, metadata !21}
!34 = metadata !{i32 5, i32 0, metadata !35, null}
!35 = metadata !{i32 786443, metadata !5, metadata !36, i32 5, i32 0, i32 5, i32 5} ; [ DW_TAG_lexical_block ] [/tmp/dbginfo/PR20038.cpp]
!36 = metadata !{i32 786443, metadata !5, metadata !12, i32 5, i32 0, i32 4, i32 4} ; [ DW_TAG_lexical_block ] [/tmp/dbginfo/PR20038.cpp]
!37 = metadata !{i32 6, i32 0, metadata !17, null}
!38 = metadata !{i32 0, i32 0, metadata !17, null}
!39 = metadata !{i32 0, i32 0, metadata !16, metadata !37}
!40 = metadata !{i32 0, i32 0, metadata !16, null}
!41 = metadata !{i32 6, i32 0, metadata !16, null}