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| # RUN: llc -O1 -start-before=greedy -stop-after=virtregrewriter -o /dev/null %s -debug-only=livedebugvars 2>&1 | FileCheck -check-prefix=CHECKDBG %s
# REQUIRES: asserts
# This test case was generated by using the following c program:
# extern void foo(int, int);
#
# int bar[2] = {1, 2};
#
# int main(int argc, char** argv)
# {
# int a0 = bar[0];
# int a1 = bar[1];
# foo(a0, a1);
# return 0;
# }
#
# It was compiled with -g and -O1, and the mir was dumped before ra greedy.
--- |
; ModuleID = 'live-debug-vars-unused-arg.ll'
source_filename = "live-debug-vars-unused-arg.c"
target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-unknown-linux-gnu"
@bar = local_unnamed_addr global [2 x i32] [i32 1, i32 2], align 4, !dbg !0
; Function Attrs: nounwind uwtable
define i32 @main(i32 %argc, i8** nocapture readnone %argv) local_unnamed_addr #0 !dbg !14 {
entry:
tail call void @llvm.dbg.value(metadata i32 %argc, metadata !21, metadata !DIExpression()), !dbg !25
tail call void @llvm.dbg.value(metadata i8** %argv, metadata !22, metadata !DIExpression()), !dbg !26
%0 = load i32, i32* getelementptr inbounds ([2 x i32], [2 x i32]* @bar, i64 0, i64 0), align 4, !dbg !27, !tbaa !28
tail call void @llvm.dbg.value(metadata i32 %0, metadata !23, metadata !DIExpression()), !dbg !32
%1 = load i32, i32* getelementptr inbounds ([2 x i32], [2 x i32]* @bar, i64 0, i64 1), align 4, !dbg !33, !tbaa !28
tail call void @llvm.dbg.value(metadata i32 %1, metadata !24, metadata !DIExpression()), !dbg !34
tail call void @foo(i32 %0, i32 %1) #2, !dbg !35
ret i32 0, !dbg !36
}
declare void @foo(i32, i32) local_unnamed_addr
; Function Attrs: nounwind readnone speculatable
declare void @llvm.dbg.value(metadata, metadata, metadata) #1
; Function Attrs: nounwind
declare void @llvm.stackprotector(i8*, i8**) #2
attributes #0 = { nounwind uwtable }
attributes #1 = { nounwind readnone speculatable }
attributes #2 = { nounwind }
!llvm.dbg.cu = !{!2}
!llvm.module.flags = !{!10, !11, !12}
!llvm.ident = !{!13}
!0 = !DIGlobalVariableExpression(var: !1, expr: !DIExpression())
!1 = distinct !DIGlobalVariable(name: "bar", scope: !2, file: !3, line: 3, type: !6, isLocal: false, isDefinition: true)
!2 = distinct !DICompileUnit(language: DW_LANG_C99, file: !3, producer: "clang version 6.0.0 (trunk 313866) (llvm/trunk 313875)", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !4, globals: !5)
!3 = !DIFile(filename: "live-debug-vars-unused-arg.c", directory: "/repo/uabbpet/master")
!4 = !{}
!5 = !{!0}
!6 = !DICompositeType(tag: DW_TAG_array_type, baseType: !7, size: 64, elements: !8)
!7 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
!8 = !{!9}
!9 = !DISubrange(count: 2)
!10 = !{i32 2, !"Dwarf Version", i32 4}
!11 = !{i32 2, !"Debug Info Version", i32 3}
!12 = !{i32 1, !"wchar_size", i32 4}
!13 = !{!"clang version 6.0.0 (trunk 313866) (llvm/trunk 313875)"}
!14 = distinct !DISubprogram(name: "main", scope: !3, file: !3, line: 5, type: !15, isLocal: false, isDefinition: true, scopeLine: 6, flags: DIFlagPrototyped, isOptimized: true, unit: !2, retainedNodes: !20)
!15 = !DISubroutineType(types: !16)
!16 = !{!7, !7, !17}
!17 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !18, size: 64)
!18 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !19, size: 64)
!19 = !DIBasicType(name: "char", size: 8, encoding: DW_ATE_signed_char)
!20 = !{!21, !22, !23, !24}
!21 = !DILocalVariable(name: "argc", arg: 1, scope: !14, file: !3, line: 5, type: !7)
!22 = !DILocalVariable(name: "argv", arg: 2, scope: !14, file: !3, line: 5, type: !17)
!23 = !DILocalVariable(name: "a0", scope: !14, file: !3, line: 7, type: !7)
!24 = !DILocalVariable(name: "a1", scope: !14, file: !3, line: 8, type: !7)
!25 = !DILocation(line: 5, column: 14, scope: !14)
!26 = !DILocation(line: 5, column: 27, scope: !14)
!27 = !DILocation(line: 7, column: 12, scope: !14)
!28 = !{!29, !29, i64 0}
!29 = !{!"int", !30, i64 0}
!30 = !{!"omnipotent char", !31, i64 0}
!31 = !{!"Simple C/C++ TBAA"}
!32 = !DILocation(line: 7, column: 7, scope: !14)
!33 = !DILocation(line: 8, column: 12, scope: !14)
!34 = !DILocation(line: 8, column: 7, scope: !14)
!35 = !DILocation(line: 9, column: 3, scope: !14)
!36 = !DILocation(line: 10, column: 3, scope: !14)
...
---
name: main
alignment: 16
exposesReturnsTwice: false
legalized: false
regBankSelected: false
selected: false
tracksRegLiveness: true
registers:
- { id: 0, class: gr32, preferred-register: '' }
- { id: 1, class: gr64, preferred-register: '' }
- { id: 2, class: gr32, preferred-register: '' }
- { id: 3, class: gr32, preferred-register: '' }
- { id: 4, class: gr32, preferred-register: '' }
liveins:
frameInfo:
isFrameAddressTaken: false
isReturnAddressTaken: false
hasStackMap: false
hasPatchPoint: false
stackSize: 0
offsetAdjustment: 0
maxAlignment: 0
adjustsStack: false
hasCalls: true
stackProtector: ''
maxCallFrameSize: 4294967295
hasOpaqueSPAdjustment: false
hasVAStart: false
hasMustTailInVarArgFunc: false
savePoint: ''
restorePoint: ''
fixedStack:
stack:
constants:
body: |
bb.0.entry:
DBG_VALUE $edi, _, !21, !DIExpression(), debug-location !25
DBG_VALUE $rsi, _, !22, !DIExpression(), debug-location !26
%2 = MOV32rm $rip, 1, _, @bar, _, debug-location !27 :: (dereferenceable load 4 from `i32* getelementptr inbounds ([2 x i32], [2 x i32]* @bar, i64 0, i64 0)`, !tbaa !28)
DBG_VALUE %2, _, !23, !DIExpression(), debug-location !32
%3 = MOV32rm $rip, 1, _, @bar + 4, _, debug-location !33 :: (dereferenceable load 4 from `i32* getelementptr inbounds ([2 x i32], [2 x i32]* @bar, i64 0, i64 1)`, !tbaa !28)
DBG_VALUE %3, _, !24, !DIExpression(), debug-location !34
ADJCALLSTACKDOWN64 0, 0, 0, implicit-def dead $rsp, implicit-def dead $eflags, implicit-def dead $ssp, implicit $rsp, implicit $ssp, debug-location !35
$edi = COPY %2, debug-location !35
$esi = COPY %3, debug-location !35
CALL64pcrel32 @foo, csr_64, implicit $rsp, implicit $ssp, implicit killed $edi, implicit killed $esi, implicit-def $rsp, debug-location !35
ADJCALLSTACKUP64 0, 0, implicit-def dead $rsp, implicit-def dead $eflags, implicit-def dead $ssp, implicit $rsp, implicit $ssp, debug-location !35
$eax = MOV32r0 implicit-def dead $eflags, debug-location !36
RET 0, killed $eax, debug-location !36
...
# Let's verify that the slot index ranges for the unused variables argc/argv,
# connected to physical regs $edi and $rsi, does not overlap with the ranges
# for %2 and %3. The register allocator is actually allocating the
# virtual registers # to $edi and $esi, so the ranges for argc/argv should
# not cover the whole BB.
#
# CHECKDBG-LABEL: ********** EMITTING LIVE DEBUG VARIABLES **********
# CHECKDBG-NEXT: !"argc,5" [0B;0e):0 Loc0=$edi
# CHECKDBG-NEXT: [0B;0e):0 %bb.0-160B
# CHECKDBG-NEXT: !"argv,5" [0B;0e):0 Loc0=$rsi
# CHECKDBG-NEXT: [0B;0e):0 %bb.0-160B
# CHECKDBG-NEXT: !"a0,7" [16r;64r):0 Loc0=%2
# CHECKDBG-NEXT: [16r;64r):0 %bb.0-160B
# CHECKDBG-NEXT: !"a1,8" [32r;80r):0 Loc0=%3
# CHECKDBG-NEXT: [32r;80r):0 %bb.0-160B
|