llvm-6502/test/DebugInfo/cross-cu-inlining.ll
Adrian Prantl 076fd5dfc1 Move the complex address expression out of DIVariable and into an extra
argument of the llvm.dbg.declare/llvm.dbg.value intrinsics.

Previously, DIVariable was a variable-length field that has an optional
reference to a Metadata array consisting of a variable number of
complex address expressions. In the case of OpPiece expressions this is
wasting a lot of storage in IR, because when an aggregate type is, e.g.,
SROA'd into all of its n individual members, the IR will contain n copies
of the DIVariable, all alike, only differing in the complex address
reference at the end.

By making the complex address into an extra argument of the
dbg.value/dbg.declare intrinsics, all of the pieces can reference the
same variable and the complex address expressions can be uniqued across
the CU, too.
Down the road, this will allow us to move other flags, such as
"indirection" out of the DIVariable, too.

The new intrinsics look like this:
declare void @llvm.dbg.declare(metadata %storage, metadata %var, metadata %expr)
declare void @llvm.dbg.value(metadata %storage, i64 %offset, metadata %var, metadata %expr)

This patch adds a new LLVM-local tag to DIExpressions, so we can detect
and pretty-print DIExpression metadata nodes.

What this patch doesn't do:

This patch does not touch the "Indirect" field in DIVariable; but moving
that into the expression would be a natural next step.

http://reviews.llvm.org/D4919
rdar://problem/17994491

Thanks to dblaikie and dexonsmith for reviewing this patch!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218778 91177308-0d34-0410-b5e6-96231b3b80d8
2014-10-01 17:55:39 +00:00

131 lines
6.4 KiB
LLVM

; REQUIRES: object-emission
; RUN: %llc_dwarf -O0 -filetype=obj < %s | llvm-dwarfdump -debug-dump=info - | FileCheck -implicit-check-not=DW_TAG %s
; Build from source:
; $ clang++ a.cpp b.cpp -g -c -emit-llvm
; $ llvm-link a.bc b.bc -o ab.bc
; $ opt -inline ab.bc -o ab-opt.bc
; $ cat a.cpp
; extern int i;
; int func(int);
; int main() {
; return func(i);
; }
; $ cat b.cpp
; int __attribute__((always_inline)) func(int x) {
; return x * 2;
; }
; Ensure that func inlined into main is described and references the abstract
; definition in b.cpp's CU.
; CHECK: DW_TAG_compile_unit
; CHECK: DW_AT_name {{.*}} "a.cpp"
; CHECK: DW_TAG_subprogram
; CHECK: DW_AT_type [DW_FORM_ref_addr] (0x00000000[[INT:.*]])
; CHECK: DW_TAG_inlined_subroutine
; CHECK: DW_AT_abstract_origin {{.*}}[[ABS_FUNC:........]])
; CHECK: DW_TAG_formal_parameter
; CHECK: DW_AT_abstract_origin {{.*}}[[ABS_VAR:........]])
; Check the abstract definition is in the 'b.cpp' CU and doesn't contain any
; concrete information (address range or variable location)
; CHECK: DW_TAG_compile_unit
; CHECK: DW_AT_name {{.*}} "b.cpp"
; CHECK: 0x[[ABS_FUNC]]: DW_TAG_subprogram
; CHECK-NOT: DW_AT_low_pc
; CHECK: 0x[[ABS_VAR]]: DW_TAG_formal_parameter
; CHECK-NOT: DW_AT_location
; CHECK: DW_AT_type [DW_FORM_ref4] {{.*}} {0x[[INT]]}
; CHECK-NOT: DW_AT_location
; CHECK: 0x[[INT]]: DW_TAG_base_type
; CHECK: DW_AT_name {{.*}} "int"
; Check the concrete out of line definition references the abstract and
; provides the address range and variable location
; CHECK: DW_TAG_subprogram
; CHECK: DW_AT_low_pc
; CHECK: DW_AT_abstract_origin {{.*}} {0x[[ABS_FUNC]]}
; CHECK: DW_TAG_formal_parameter
; CHECK: DW_AT_location
; CHECK: DW_AT_abstract_origin {{.*}} {0x[[ABS_VAR]]}
@i = external global i32
; Function Attrs: uwtable
define i32 @main() #0 {
entry:
%x.addr.i = alloca i32, align 4
%retval = alloca i32, align 4
store i32 0, i32* %retval
%0 = load i32* @i, align 4, !dbg !19
%1 = bitcast i32* %x.addr.i to i8*
call void @llvm.lifetime.start(i64 4, i8* %1)
store i32 %0, i32* %x.addr.i, align 4
call void @llvm.dbg.declare(metadata !{i32* %x.addr.i}, metadata !20, metadata !{}), !dbg !21
%2 = load i32* %x.addr.i, align 4, !dbg !22
%mul.i = mul nsw i32 %2, 2, !dbg !22
%3 = bitcast i32* %x.addr.i to i8*, !dbg !22
call void @llvm.lifetime.end(i64 4, i8* %3), !dbg !22
ret i32 %mul.i, !dbg !19
}
; Function Attrs: alwaysinline nounwind uwtable
define i32 @_Z4funci(i32 %x) #1 {
entry:
%x.addr = alloca i32, align 4
store i32 %x, i32* %x.addr, align 4
call void @llvm.dbg.declare(metadata !{i32* %x.addr}, metadata !20, metadata !{}), !dbg !23
%0 = load i32* %x.addr, align 4, !dbg !24
%mul = mul nsw i32 %0, 2, !dbg !24
ret i32 %mul, !dbg !24
}
; Function Attrs: nounwind readnone
declare void @llvm.dbg.declare(metadata, metadata, metadata) #2
; Function Attrs: nounwind
declare void @llvm.lifetime.start(i64, i8* nocapture) #3
; Function Attrs: nounwind
declare void @llvm.lifetime.end(i64, i8* nocapture) #3
attributes #0 = { uwtable "less-precise-fpmad"="false" "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf" "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 = { alwaysinline nounwind uwtable "less-precise-fpmad"="false" "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "stack-protector-buffer-size"="8" "unsafe-fp-math"="false" "use-soft-float"="false" }
attributes #2 = { nounwind readnone }
attributes #3 = { nounwind }
!llvm.dbg.cu = !{!0, !9}
!llvm.module.flags = !{!16, !17}
!llvm.ident = !{!18, !18}
!0 = metadata !{i32 786449, metadata !1, i32 4, metadata !"clang version 3.5.0 ", i1 false, metadata !"", i32 0, metadata !2, metadata !2, metadata !3, metadata !2, metadata !2, metadata !"", i32 1} ; [ DW_TAG_compile_unit ] [/tmp/dbginfo/a.cpp] [DW_LANG_C_plus_plus]
!1 = metadata !{metadata !"a.cpp", metadata !"/tmp/dbginfo"}
!2 = metadata !{}
!3 = metadata !{metadata !4}
!4 = metadata !{i32 786478, metadata !1, metadata !5, metadata !"main", metadata !"main", metadata !"", i32 3, metadata !6, i1 false, i1 true, i32 0, i32 0, null, i32 256, i1 false, i32 ()* @main, null, null, metadata !2, i32 3} ; [ DW_TAG_subprogram ] [line 3] [def] [main]
!5 = metadata !{i32 786473, metadata !1} ; [ DW_TAG_file_type ] [/tmp/dbginfo/a.cpp]
!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 !{metadata !8}
!8 = 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]
!9 = metadata !{i32 786449, metadata !10, i32 4, metadata !"clang version 3.5.0 ", i1 false, metadata !"", i32 0, metadata !2, metadata !2, metadata !11, metadata !2, metadata !2, metadata !"", i32 1} ; [ DW_TAG_compile_unit ] [/tmp/dbginfo/b.cpp] [DW_LANG_C_plus_plus]
!10 = metadata !{metadata !"b.cpp", metadata !"/tmp/dbginfo"}
!11 = metadata !{metadata !12}
!12 = metadata !{i32 786478, metadata !10, metadata !13, metadata !"func", metadata !"func", metadata !"_Z4funci", i32 1, metadata !14, i1 false, i1 true, i32 0, i32 0, null, i32 256, i1 false, i32 (i32)* @_Z4funci, null, null, metadata !2, i32 1} ; [ DW_TAG_subprogram ] [line 1] [def] [func]
!13 = metadata !{i32 786473, metadata !10} ; [ DW_TAG_file_type ] [/tmp/dbginfo/b.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 !{metadata !8, metadata !8}
!16 = metadata !{i32 2, metadata !"Dwarf Version", i32 4}
!17 = metadata !{i32 2, metadata !"Debug Info Version", i32 1}
!18 = metadata !{metadata !"clang version 3.5.0 "}
!19 = metadata !{i32 4, i32 0, metadata !4, null}
!20 = metadata !{i32 786689, metadata !12, metadata !"x", metadata !13, i32 16777217, metadata !8, i32 0, i32 0} ; [ DW_TAG_arg_variable ] [x] [line 1]
!21 = metadata !{i32 1, i32 0, metadata !12, metadata !19}
!22 = metadata !{i32 2, i32 0, metadata !12, metadata !19}
!23 = metadata !{i32 1, i32 0, metadata !12, null}
!24 = metadata !{i32 2, i32 0, metadata !12, null}