llvm/test/DebugInfo/X86/fission-ranges.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

201 lines
11 KiB
LLVM

; RUN: llc -split-dwarf=Enable -O0 %s -mtriple=x86_64-unknown-linux-gnu -filetype=obj -o %t
; RUN: llvm-dwarfdump %t | FileCheck %s
; RUN: llvm-objdump -h %t | FileCheck --check-prefix=HDR %s
; CHECK: .debug_info contents:
; CHECK: DW_TAG_compile_unit
; CHECK-NEXT: DW_AT_stmt_list
; CHECK-NEXT: DW_AT_GNU_dwo_name
; CHECK-NEXT: DW_AT_comp_dir
; CHECK-NEXT: DW_AT_GNU_dwo_id
; CHECK-NEXT: DW_AT_GNU_addr_base [DW_FORM_sec_offset] (0x00000000)
; CHECK: .debug_info.dwo contents:
; CHECK: DW_AT_location [DW_FORM_sec_offset] ([[A:0x[0-9a-z]*]])
; CHECK: DW_AT_location [DW_FORM_sec_offset] ([[E:0x[0-9a-z]*]])
; CHECK: DW_AT_location [DW_FORM_sec_offset] ([[B:0x[0-9a-z]*]])
; CHECK: DW_AT_location [DW_FORM_sec_offset] ([[D:0x[0-9a-z]*]])
; CHECK: DW_AT_ranges [DW_FORM_sec_offset] (0x00000000)
; CHECK: .debug_loc contents:
; CHECK-NOT: Beginning address offset
; CHECK: .debug_loc.dwo contents:
; Don't assume these locations are entirely correct - feel free to update them
; if they've changed due to a bugfix, change in register allocation, etc.
; CHECK: [[A]]: Beginning address index: 2
; CHECK-NEXT: Length: 190
; CHECK-NEXT: Location description: 11 00
; CHECK-NEXT: {{^$}}
; CHECK-NEXT: Beginning address index: 3
; CHECK-NEXT: Length: 23
; CHECK-NEXT: Location description: 50 93 04
; CHECK: [[E]]: Beginning address index: 4
; CHECK-NEXT: Length: 21
; CHECK-NEXT: Location description: 50 93 04
; CHECK: [[B]]: Beginning address index: 5
; CHECK-NEXT: Length: 19
; CHECK-NEXT: Location description: 50 93 04
; CHECK: [[D]]: Beginning address index: 6
; CHECK-NEXT: Length: 23
; CHECK-NEXT: Location description: 50 93 04
; Make sure we don't produce any relocations in any .dwo section (though in particular, debug_info.dwo)
; HDR-NOT: .rela.{{.*}}.dwo
; Make sure we have enough stuff in the debug_addr to cover the address indexes
; (6 is the last index in debug_loc.dwo, making 7 entries of 8 bytes each, 7 * 8
; == 56 base 10 == 38 base 16)
; HDR: .debug_addr 00000038
; HDR-NOT: .rela.{{.*}}.dwo
; From the code:
; extern int c;
; static void foo (int p)
; {
; int a, b;
; unsigned int d, e;
; for (a = 0; a < 30; a++)
; for (d = 0; d < 30; d++)
; for (b = 0; b < 30; b++)
; for (e = 0; e < 30; e++)
; {
; int *w = &c;
; *w &= p;
; }
; }
; void
; bar ()
; {
; foo (1);
; }
; compiled with:
; clang -g -S -gsplit-dwarf -O1 small.c
@c = external global i32
; Function Attrs: nounwind uwtable
define void @bar() #0 {
entry:
tail call fastcc void @foo(), !dbg !27
ret void, !dbg !28
}
; Function Attrs: nounwind uwtable
define internal fastcc void @foo() #0 {
entry:
tail call void @llvm.dbg.value(metadata !29, i64 0, metadata !13), !dbg !30
tail call void @llvm.dbg.value(metadata !44, i64 0, metadata !14), !dbg !31
%c.promoted9 = load i32* @c, align 4, !dbg !32, !tbaa !33
br label %for.cond1.preheader, !dbg !31
for.cond1.preheader: ; preds = %for.inc16, %entry
%and.lcssa.lcssa.lcssa10 = phi i32 [ %c.promoted9, %entry ], [ %and, %for.inc16 ]
%a.08 = phi i32 [ 0, %entry ], [ %inc17, %for.inc16 ]
br label %for.cond4.preheader, !dbg !37
for.cond4.preheader: ; preds = %for.inc13, %for.cond1.preheader
%and.lcssa.lcssa7 = phi i32 [ %and.lcssa.lcssa.lcssa10, %for.cond1.preheader ], [ %and, %for.inc13 ]
%d.06 = phi i32 [ 0, %for.cond1.preheader ], [ %inc14, %for.inc13 ]
br label %for.cond7.preheader, !dbg !38
for.cond7.preheader: ; preds = %for.inc10, %for.cond4.preheader
%and.lcssa5 = phi i32 [ %and.lcssa.lcssa7, %for.cond4.preheader ], [ %and, %for.inc10 ]
%b.03 = phi i32 [ 0, %for.cond4.preheader ], [ %inc11, %for.inc10 ]
br label %for.body9, !dbg !39
for.body9: ; preds = %for.body9, %for.cond7.preheader
%and2 = phi i32 [ %and.lcssa5, %for.cond7.preheader ], [ %and, %for.body9 ], !dbg !40
%e.01 = phi i32 [ 0, %for.cond7.preheader ], [ %inc, %for.body9 ]
tail call void @llvm.dbg.value(metadata !41, i64 0, metadata !19), !dbg !40
%and = and i32 %and2, 1, !dbg !32
%inc = add i32 %e.01, 1, !dbg !39
tail call void @llvm.dbg.value(metadata !{i32 %inc}, i64 0, metadata !18), !dbg !39
%exitcond = icmp eq i32 %inc, 30, !dbg !39
br i1 %exitcond, label %for.inc10, label %for.body9, !dbg !39
for.inc10: ; preds = %for.body9
%inc11 = add nsw i32 %b.03, 1, !dbg !38
tail call void @llvm.dbg.value(metadata !{i32 %inc11}, i64 0, metadata !15), !dbg !38
%exitcond11 = icmp eq i32 %inc11, 30, !dbg !38
br i1 %exitcond11, label %for.inc13, label %for.cond7.preheader, !dbg !38
for.inc13: ; preds = %for.inc10
%inc14 = add i32 %d.06, 1, !dbg !37
tail call void @llvm.dbg.value(metadata !{i32 %inc14}, i64 0, metadata !16), !dbg !37
%exitcond12 = icmp eq i32 %inc14, 30, !dbg !37
br i1 %exitcond12, label %for.inc16, label %for.cond4.preheader, !dbg !37
for.inc16: ; preds = %for.inc13
%inc17 = add nsw i32 %a.08, 1, !dbg !31
tail call void @llvm.dbg.value(metadata !{i32 %inc17}, i64 0, metadata !14), !dbg !31
%exitcond13 = icmp eq i32 %inc17, 30, !dbg !31
br i1 %exitcond13, label %for.end18, label %for.cond1.preheader, !dbg !31
for.end18: ; preds = %for.inc16
store i32 %and, i32* @c, align 4, !dbg !32, !tbaa !33
ret void, !dbg !42
}
; Function Attrs: nounwind readnone
declare void @llvm.dbg.value(metadata, i64, metadata) #1
attributes #0 = { nounwind uwtable "less-precise-fpmad"="false" "no-frame-pointer-elim"="false" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "stack-protector-buffer-size"="8" "unsafe-fp-math"="false" "use-soft-float"="false" }
attributes #1 = { nounwind readnone }
!llvm.dbg.cu = !{!0}
!llvm.module.flags = !{!26, !43}
!0 = metadata !{i32 786449, metadata !1, i32 12, metadata !"clang version 3.4 (trunk 191700) (llvm/trunk 191710)", i1 true, metadata !"", i32 0, metadata !2, metadata !2, metadata !3, metadata !2, metadata !2, metadata !"small.dwo"} ; [ DW_TAG_compile_unit ] [/usr/local/google/home/echristo/tmp/small.c] [DW_LANG_C99]
!1 = metadata !{metadata !"small.c", metadata !"/usr/local/google/home/echristo/tmp"}
!2 = metadata !{}
!3 = metadata !{metadata !4, metadata !8}
!4 = metadata !{i32 786478, metadata !1, metadata !5, metadata !"bar", metadata !"bar", metadata !"", i32 18, metadata !6, i1 false, i1 true, i32 0, i32 0, null, i32 0, i1 true, void ()* @bar, null, null, metadata !2, i32 19} ; [ DW_TAG_subprogram ] [line 18] [def] [scope 19] [bar]
!5 = metadata !{i32 786473, metadata !1} ; [ DW_TAG_file_type ] [/usr/local/google/home/echristo/tmp/small.c]
!6 = metadata !{i32 786453, i32 0, null, metadata !"", i32 0, i64 0, i64 0, i64 0, i32 0, null, metadata !7, i32 0, null, null, null} ; [ DW_TAG_subroutine_type ] [line 0, size 0, align 0, offset 0] [from ]
!7 = metadata !{null}
!8 = metadata !{i32 786478, metadata !1, metadata !5, metadata !"foo", metadata !"foo", metadata !"", i32 2, metadata !9, i1 true, i1 true, i32 0, i32 0, null, i32 256, i1 true, void ()* @foo, null, null, metadata !12, i32 3} ; [ DW_TAG_subprogram ] [line 2] [local] [def] [scope 3] [foo]
!9 = metadata !{i32 786453, i32 0, null, metadata !"", i32 0, i64 0, i64 0, i64 0, i32 0, null, metadata !10, i32 0, null, null, null} ; [ DW_TAG_subroutine_type ] [line 0, size 0, align 0, offset 0] [from ]
!10 = metadata !{null, metadata !11}
!11 = metadata !{i32 786468, null, null, metadata !"int", i32 0, i64 32, i64 32, i64 0, i32 0, i32 5} ; [ DW_TAG_base_type ] [int] [line 0, size 32, align 32, offset 0, enc DW_ATE_signed]
!12 = metadata !{metadata !13, metadata !14, metadata !15, metadata !16, metadata !18, metadata !19}
!13 = metadata !{i32 786689, metadata !8, metadata !"p", metadata !5, i32 16777218, metadata !11, i32 0, i32 0} ; [ DW_TAG_arg_variable ] [p] [line 2]
!14 = metadata !{i32 786688, metadata !8, metadata !"a", metadata !5, i32 4, metadata !11, i32 0, i32 0} ; [ DW_TAG_auto_variable ] [a] [line 4]
!15 = metadata !{i32 786688, metadata !8, metadata !"b", metadata !5, i32 4, metadata !11, i32 0, i32 0} ; [ DW_TAG_auto_variable ] [b] [line 4]
!16 = metadata !{i32 786688, metadata !8, metadata !"d", metadata !5, i32 5, metadata !17, i32 0, i32 0} ; [ DW_TAG_auto_variable ] [d] [line 5]
!17 = metadata !{i32 786468, null, null, metadata !"unsigned int", i32 0, i64 32, i64 32, i64 0, i32 0, i32 7} ; [ DW_TAG_base_type ] [unsigned int] [line 0, size 32, align 32, offset 0, enc DW_ATE_unsigned]
!18 = metadata !{i32 786688, metadata !8, metadata !"e", metadata !5, i32 5, metadata !17, i32 0, i32 0} ; [ DW_TAG_auto_variable ] [e] [line 5]
!19 = metadata !{i32 786688, metadata !20, metadata !"w", metadata !5, i32 12, metadata !25, i32 0, i32 0} ; [ DW_TAG_auto_variable ] [w] [line 12]
!20 = metadata !{i32 786443, metadata !1, metadata !21, i32 11, i32 0, i32 4} ; [ DW_TAG_lexical_block ] [/usr/local/google/home/echristo/tmp/small.c]
!21 = metadata !{i32 786443, metadata !1, metadata !22, i32 10, i32 0, i32 3} ; [ DW_TAG_lexical_block ] [/usr/local/google/home/echristo/tmp/small.c]
!22 = metadata !{i32 786443, metadata !1, metadata !23, i32 9, i32 0, i32 2} ; [ DW_TAG_lexical_block ] [/usr/local/google/home/echristo/tmp/small.c]
!23 = metadata !{i32 786443, metadata !1, metadata !24, i32 8, i32 0, i32 1} ; [ DW_TAG_lexical_block ] [/usr/local/google/home/echristo/tmp/small.c]
!24 = metadata !{i32 786443, metadata !1, metadata !8, i32 7, i32 0, i32 0} ; [ DW_TAG_lexical_block ] [/usr/local/google/home/echristo/tmp/small.c]
!25 = metadata !{i32 786447, null, null, metadata !"", i32 0, i64 64, i64 64, i64 0, i32 0, metadata !11} ; [ DW_TAG_pointer_type ] [line 0, size 64, align 64, offset 0] [from int]
!26 = metadata !{i32 2, metadata !"Dwarf Version", i32 4}
!27 = metadata !{i32 20, i32 0, metadata !4, null}
!28 = metadata !{i32 21, i32 0, metadata !4, null}
!29 = metadata !{i32 1}
!30 = metadata !{i32 2, i32 0, metadata !8, null}
!31 = metadata !{i32 7, i32 0, metadata !24, null}
!32 = metadata !{i32 13, i32 0, metadata !20, null}
!33 = metadata !{metadata !34, metadata !34, i64 0}
!34 = metadata !{metadata !"int", metadata !35, i64 0}
!35 = metadata !{metadata !"omnipotent char", metadata !36, i64 0}
!36 = metadata !{metadata !"Simple C/C++ TBAA"}
!37 = metadata !{i32 8, i32 0, metadata !23, null} ; [ DW_TAG_imported_declaration ]
!38 = metadata !{i32 9, i32 0, metadata !22, null}
!39 = metadata !{i32 10, i32 0, metadata !21, null}
!40 = metadata !{i32 12, i32 0, metadata !20, null}
!41 = metadata !{i32* @c}
!42 = metadata !{i32 15, i32 0, metadata !8, null}
!43 = metadata !{i32 1, metadata !"Debug Info Version", i32 1}
!44 = metadata !{i32 0}