llvm/test/DebugInfo/X86/vla.ll
Keno Fischer bae9026417 Clean up the processing of dbg.value in various places
Summary:
First up is instcombine, where in the dbg.declare -> dbg.value conversion,
the llvm.dbg.value needs to be called on the actual loaded value, rather
than the address (since the whole point of this transformation is to be
able to get rid of the alloca). Further, now that that's cleaned up, we
can remove a hack in the backend, that would add an implicit OP_deref if
the argument to dbg.value was an alloca. This stems from before the
existence of DIExpression and is no longer necessary since the deref can
be expressed explicitly.

Now, in order to make sure that the tests pass with this change, we need to
correct the printing of DEBUG_VALUE comments to take into account the
expression, which wasn't taken into account before.

Unfortunately, for both these changes, there were a number of incorrect
test cases (mostly the wrong number of DW_OP_derefs, but also a couple
where the test itself was broken more badly). aprantl and I have gone
through and adjusted these test case in order to make them pass with
these fixes and in some cases to make sure they're actually testing
what they are meant to test.

Reviewers: aprantl

Subscribers: dsanders

Differential Revision: http://reviews.llvm.org/D14186

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@256077 91177308-0d34-0410-b5e6-96231b3b80d8
2015-12-19 02:02:44 +00:00

108 lines
4.7 KiB
LLVM

; RUN: llc -O0 -mtriple=x86_64-apple-darwin -filetype=asm %s -o - | FileCheck %s
; Ensure that we generate an indirect location for the variable length array a.
; CHECK: ##DEBUG_VALUE: vla:a <- [%RDX+0]
; CHECK: DW_OP_breg1
; rdar://problem/13658587
;
; generated from:
;
; int vla(int n) {
; int a[n];
; a[0] = 42;
; return a[n-1];
; }
;
; int main(int argc, char** argv) {
; return vla(argc);
; }
; ModuleID = 'vla.c'
target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128"
target triple = "x86_64-apple-macosx10.8.0"
; Function Attrs: nounwind ssp uwtable
define i32 @vla(i32 %n) nounwind ssp uwtable !dbg !4 {
entry:
%n.addr = alloca i32, align 4
%saved_stack = alloca i8*
%cleanup.dest.slot = alloca i32
store i32 %n, i32* %n.addr, align 4
call void @llvm.dbg.declare(metadata i32* %n.addr, metadata !15, metadata !DIExpression()), !dbg !16
%0 = load i32, i32* %n.addr, align 4, !dbg !17
%1 = zext i32 %0 to i64, !dbg !17
%2 = call i8* @llvm.stacksave(), !dbg !17
store i8* %2, i8** %saved_stack, !dbg !17
%vla = alloca i32, i64 %1, align 16, !dbg !17
call void @llvm.dbg.declare(metadata i32* %vla, metadata !18, metadata !DIExpression(DW_OP_deref)), !dbg !17
%arrayidx = getelementptr inbounds i32, i32* %vla, i64 0, !dbg !22
store i32 42, i32* %arrayidx, align 4, !dbg !22
%3 = load i32, i32* %n.addr, align 4, !dbg !23
%sub = sub nsw i32 %3, 1, !dbg !23
%idxprom = sext i32 %sub to i64, !dbg !23
%arrayidx1 = getelementptr inbounds i32, i32* %vla, i64 %idxprom, !dbg !23
%4 = load i32, i32* %arrayidx1, align 4, !dbg !23
store i32 1, i32* %cleanup.dest.slot
%5 = load i8*, i8** %saved_stack, !dbg !24
call void @llvm.stackrestore(i8* %5), !dbg !24
ret i32 %4, !dbg !23
}
; Function Attrs: nounwind readnone
declare void @llvm.dbg.declare(metadata, metadata, metadata) nounwind readnone
; Function Attrs: nounwind
declare i8* @llvm.stacksave() nounwind
; Function Attrs: nounwind
declare void @llvm.stackrestore(i8*) nounwind
; Function Attrs: nounwind ssp uwtable
define i32 @main(i32 %argc, i8** %argv) nounwind ssp uwtable !dbg !9 {
entry:
%retval = alloca i32, align 4
%argc.addr = alloca i32, align 4
%argv.addr = alloca i8**, align 8
store i32 0, i32* %retval
store i32 %argc, i32* %argc.addr, align 4
call void @llvm.dbg.declare(metadata i32* %argc.addr, metadata !25, metadata !DIExpression()), !dbg !26
store i8** %argv, i8*** %argv.addr, align 8
call void @llvm.dbg.declare(metadata i8*** %argv.addr, metadata !27, metadata !DIExpression()), !dbg !26
%0 = load i32, i32* %argc.addr, align 4, !dbg !28
%call = call i32 @vla(i32 %0), !dbg !28
ret i32 %call, !dbg !28
}
!llvm.dbg.cu = !{!0}
!llvm.module.flags = !{!29}
!0 = distinct !DICompileUnit(language: DW_LANG_C99, producer: "clang version 3.3 ", isOptimized: false, emissionKind: 1, file: !1, enums: !2, retainedTypes: !2, subprograms: !3, globals: !2, imports: !2)
!1 = !DIFile(filename: "vla.c", directory: "")
!2 = !{}
!3 = !{!4, !9}
!4 = distinct !DISubprogram(name: "vla", line: 1, isLocal: false, isDefinition: true, virtualIndex: 6, flags: DIFlagPrototyped, isOptimized: false, scopeLine: 1, file: !1, scope: !5, type: !6, variables: !2)
!5 = !DIFile(filename: "vla.c", directory: "")
!6 = !DISubroutineType(types: !7)
!7 = !{!8, !8}
!8 = !DIBasicType(tag: DW_TAG_base_type, name: "int", size: 32, align: 32, encoding: DW_ATE_signed)
!9 = distinct !DISubprogram(name: "main", line: 7, isLocal: false, isDefinition: true, virtualIndex: 6, flags: DIFlagPrototyped, isOptimized: false, scopeLine: 7, file: !1, scope: !5, type: !10, variables: !2)
!10 = !DISubroutineType(types: !11)
!11 = !{!8, !8, !12}
!12 = !DIDerivedType(tag: DW_TAG_pointer_type, size: 64, align: 64, baseType: !13)
!13 = !DIDerivedType(tag: DW_TAG_pointer_type, size: 64, align: 64, baseType: !14)
!14 = !DIBasicType(tag: DW_TAG_base_type, name: "char", size: 8, align: 8, encoding: DW_ATE_signed_char)
!15 = !DILocalVariable(name: "n", line: 1, arg: 1, scope: !4, file: !5, type: !8)
!16 = !DILocation(line: 1, scope: !4)
!17 = !DILocation(line: 2, scope: !4)
!18 = !DILocalVariable(name: "a", line: 2, scope: !4, file: !5, type: !19)
!19 = !DICompositeType(tag: DW_TAG_array_type, align: 32, baseType: !8, elements: !20)
!20 = !{!21}
!21 = !DISubrange(count: -1)
!22 = !DILocation(line: 3, scope: !4)
!23 = !DILocation(line: 4, scope: !4)
!24 = !DILocation(line: 5, scope: !4)
!25 = !DILocalVariable(name: "argc", line: 7, arg: 1, scope: !9, file: !5, type: !8)
!26 = !DILocation(line: 7, scope: !9)
!27 = !DILocalVariable(name: "argv", line: 7, arg: 2, scope: !9, file: !5, type: !12)
!28 = !DILocation(line: 8, scope: !9)
!29 = !{i32 1, !"Debug Info Version", i32 3}