--- |
; RUN: llc %s -march=x86-64 -run-pass=livedebugvalues -o - -experimental-debug-variable-locations -emulate-old-livedebugvalues=0 | FileCheck %s -implicit-check-not=DBG_VALUE
; Sometimes, variables can have multiple locations, and when control flow
; merges LiveDebugValues has a hard time picking which one the variable lives
; in. Test two of these scenarios that old LiveDebugValues can't handle: when
; a value is in two registers, and when a value is both in a register and
; on the stack.
; In a register:
; CHECK-LABEL: bb.0.entry:
; CHECK: DBG_VALUE $rbp, $noreg, !16, !DIExpression()
; CHECK-LABEL: bb.1.bb1:
; CHECK: DBG_VALUE $rbp, $noreg, !16, !DIExpression()
; CHECK: DBG_VALUE $rbp, $noreg, !16, !DIExpression()
; CHECK-LABEL: bb.2.bb2:
; CHECK: DBG_VALUE $rbp, $noreg, !16, !DIExpression()
; CHECK-LABEL: bb.3.bb3:
; CHECK: DBG_VALUE $rbp, $noreg, !16, !DIExpression()
; On the stack: we move from $rbp to a stack slot in bb4, but join back on
; $rbp in bb6.
; CHECK-LABEL: bb.4:
; CHECK: DBG_VALUE $rbp, $noreg, !16, !DIExpression()
; CHECK: DBG_VALUE $rsp, 0, !16, !DIExpression()
; CHECK-LABEL: bb.5:
; CHECK: DBG_VALUE $rbp, $noreg, !16, !DIExpression()
; CHECK-LABEL: bb.6:
; CHECK: DBG_VALUE $rbp, $noreg, !16, !DIExpression()
declare i64 @bees(i64 %arg);
define i32 @_Z8bb_to_bb(i64 %arg) local_unnamed_addr !dbg !12 {
entry:
br label %bb1, !dbg !17
bb1:
br label %bb2, !dbg !17
bb2:
br label %bb3, !dbg !17
bb3:
ret i32 0, !dbg !17
}
!llvm.dbg.cu = !{!0}
!llvm.module.flags = !{!7, !8, !9, !10}
!llvm.ident = !{!11}
!0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, file: !1, producer: "clang version 10.0.0", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !2, globals: !3, debugInfoForProfiling: true, nameTableKind: None)
!1 = !DIFile(filename: "main.cpp", directory: "F:\")
!2 = !{}
!3 = !{!4}
!4 = !DIGlobalVariableExpression(var: !5, expr: !DIExpression())
!5 = distinct !DIGlobalVariable(name: "start", scope: !0, file: !1, line: 4, type: !6, isLocal: false, isDefinition: true)
!6 = !DIBasicType(name: "int", size: 64, encoding: DW_ATE_signed)
!7 = !{i32 2, !"Dwarf Version", i32 4}
!8 = !{i32 2, !"Debug Info Version", i32 3}
!9 = !{i32 1, !"wchar_size", i32 2}
!10 = !{i32 7, !"PIC Level", i32 2}
!11 = !{!"clang version 10.0.0"}
!12 = distinct !DISubprogram(name: "bb_to_bb", linkageName: "bb_to_bb", scope: !1, file: !1, line: 6, type: !13, scopeLine: 6, flags: DIFlagPrototyped, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !0, retainedNodes: !15)
!13 = !DISubroutineType(types: !14)
!14 = !{!6, !6}
!15 = !{!16}
!16 = !DILocalVariable(name: "myVar", scope: !12, file: !1, line: 7, type: !6)
!17 = !DILocation(line: 10, scope: !12)
...
---
name: _Z8bb_to_bb
tracksRegLiveness: true
debugInstrRef: true
liveins:
- { reg: '$rdi', virtual-reg: '' }
stack:
- { id: 0, name: '', type: spill-slot, offset: -8, size: 8, alignment: 8,
stack-id: default, callee-saved-register: '', callee-saved-restored: true,
debug-info-variable: '', debug-info-expression: '', debug-info-location: '' }
body: |
bb.0.entry:
liveins: $rdi
successors: %bb.1, %bb.2
$rbp = MOV64rr $rdi, debug-location !17
DBG_VALUE $rbp, $noreg, !16, !DIExpression(), debug-location !17
dead $rcx = MOV64ri 0, debug-location !17
CALL64pcrel32 @bees, csr_64, implicit $rsp, implicit $ssp, implicit $rdi, implicit-def $rsp, implicit-def $ssp, implicit-def $rax, debug-location !17
CMP64ri8 renamable $rax, 1, implicit-def $eflags, debug-location !17
JCC_1 %bb.2, 4, implicit killed $eflags, debug-location !17
bb.1.bb1:
liveins: $rax, $rbp
successors: %bb.3
$rbp = MOV64ri 0, debug-location !17
DBG_VALUE $rbp, $noreg, !16, !DIExpression(), debug-location !17
JMP_1 %bb.3
bb.2.bb2:
liveins: $rax, $rbp
successors: %bb.3
$rax = MOV64ri 0, debug-location !17
bb.3.bb3:
liveins: $rax, $rbp
$rdi = MOV64rr $rbp, debug-location !17
CALL64pcrel32 @bees, csr_64, implicit $rsp, implicit $ssp, implicit $rdi, implicit-def $rsp, implicit-def $ssp, implicit-def $rax, debug-location !17
CMP64ri8 renamable $rax, 1, implicit-def $eflags, debug-location !17
JCC_1 %bb.5, 4, implicit killed $eflags, debug-location !17
bb.4:
liveins: $rax, $rbp
MOV64mr $rsp, 1, $noreg, 8, $noreg, killed renamable $rbp :: (store (s64) into %stack.0)
JMP_1 %bb.6
bb.5:
liveins: $rax, $rbp
bb.6:
liveins: $rax, $rbp
RET64 $rax, debug-location !17
...
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