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|
# RUN: llc -run-pass=livedebugvalues -o - %s | FileCheck %s
# Based on the following C reproducer:
#
# extern void ext(int *);
# extern int interesting(int *);
# extern int *value(void);
#
# static void callee(int *p1, int *p2) {
# if (interesting(p2))
# for (;;)
# ext(p1);
# ext(p2);
# }
#
# void caller() {
# int *local = value();
# callee(local, (int *)0xabcd);
# }
#
# Generated using:
#
# clang -Os -fno-inline -Xclang -femit-debug-entry-values -g --target=armeb.
--- |
target datalayout = "E-m:e-p:32:32-Fi8-i64:64-v128:64:128-a:0:32-n32-S64"
target triple = "armebv4t-unknown-unknown"
; Function Attrs: noinline nounwind optsize
define arm_aapcs_vfpcc void @caller() #0 !dbg !20 {
entry:
unreachable
}
; Function Attrs: noinline nounwind optsize
define internal arm_aapcs_vfpcc void @callee(i32* %p1) unnamed_addr #0 !dbg !29 {
entry:
unreachable
}
declare !dbg !4 arm_aapcs_vfpcc i32* @value()
declare !dbg !9 arm_aapcs_vfpcc i32 @interesting(i32*)
declare !dbg !12 arm_aapcs_vfpcc void @ext(i32*)
; Function Attrs: nounwind readnone speculatable willreturn
declare void @llvm.dbg.value(metadata, metadata, metadata) #1
attributes #0 = { noinline nounwind optsize "frame-pointer"="all" }
attributes #1 = { nounwind readnone speculatable willreturn }
!llvm.dbg.cu = !{!0}
!llvm.module.flags = !{!15, !16, !17, !18}
!llvm.ident = !{!19}
!0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, producer: "clang version 10.0.0", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !2, retainedTypes: !3, nameTableKind: None)
!1 = !DIFile(filename: "armeb.c", directory: "/")
!2 = !{}
!3 = !{!4, !7, !9, !12}
!4 = !DISubprogram(name: "value", scope: !1, file: !1, line: 3, type: !5, flags: DIFlagPrototyped, spFlags: DISPFlagOptimized, retainedNodes: !2)
!5 = !DISubroutineType(types: !6)
!6 = !{!7}
!7 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !8, size: 32)
!8 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
!9 = !DISubprogram(name: "interesting", scope: !1, file: !1, line: 2, type: !10, flags: DIFlagPrototyped, spFlags: DISPFlagOptimized, retainedNodes: !2)
!10 = !DISubroutineType(types: !11)
!11 = !{!8, !7}
!12 = !DISubprogram(name: "ext", scope: !1, file: !1, line: 1, type: !13, flags: DIFlagPrototyped, spFlags: DISPFlagOptimized, retainedNodes: !2)
!13 = !DISubroutineType(types: !14)
!14 = !{null, !7}
!15 = !{i32 2, !"Dwarf Version", i32 4}
!16 = !{i32 2, !"Debug Info Version", i32 3}
!17 = !{i32 1, !"wchar_size", i32 4}
!18 = !{i32 1, !"min_enum_size", i32 4}
!19 = !{!"clang version 10.0.0"}
!20 = distinct !DISubprogram(name: "caller", scope: !1, file: !1, line: 12, type: !21, scopeLine: 12, flags: DIFlagAllCallsDescribed, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !0, retainedNodes: !23)
!21 = !DISubroutineType(types: !22)
!22 = !{null}
!23 = !{!24}
!24 = !DILocalVariable(name: "local", scope: !20, file: !1, line: 13, type: !7)
!25 = !DILocation(line: 13, scope: !20)
!26 = !DILocation(line: 0, scope: !20)
!27 = !DILocation(line: 14, scope: !20)
!28 = !DILocation(line: 15, scope: !20)
!29 = distinct !DISubprogram(name: "callee", scope: !1, file: !1, line: 5, type: !30, scopeLine: 5, flags: DIFlagPrototyped | DIFlagAllCallsDescribed, spFlags: DISPFlagLocalToUnit | DISPFlagDefinition | DISPFlagOptimized, unit: !0, retainedNodes: !32)
!30 = !DISubroutineType(types: !31)
!31 = !{null, !7, !7}
!32 = !{!33, !34}
!33 = !DILocalVariable(name: "p1", arg: 1, scope: !29, file: !1, line: 5, type: !7)
!34 = !DILocalVariable(name: "p2", arg: 2, scope: !29, file: !1, line: 5, type: !7)
!35 = !DILocation(line: 0, scope: !29)
!36 = !DILocation(line: 6, scope: !37)
!37 = distinct !DILexicalBlock(scope: !29, file: !1, line: 6)
!38 = !DILocation(line: 6, scope: !29)
!39 = !DILocation(line: 7, scope: !40)
!40 = distinct !DILexicalBlock(scope: !37, file: !1, line: 7)
!41 = !DILocation(line: 8, scope: !42)
!42 = distinct !DILexicalBlock(scope: !40, file: !1, line: 7)
!43 = !DILocation(line: 7, scope: !42)
!44 = distinct !{!44, !39, !45}
!45 = !DILocation(line: 8, scope: !40)
!46 = !DILocation(line: 9, scope: !29)
!47 = !DILocation(line: 10, scope: !29)
...
---
name: caller
alignment: 4
tracksRegLiveness: true
body: |
bb.0:
liveins: $lr
$sp = frame-setup STMDB_UPD $sp, 14, $noreg, $r11, killed $lr
frame-setup CFI_INSTRUCTION def_cfa_offset 8
frame-setup CFI_INSTRUCTION offset $lr, -4
frame-setup CFI_INSTRUCTION offset $r11, -8
$r11 = frame-setup MOVr $sp, 14, $noreg, $noreg
frame-setup CFI_INSTRUCTION def_cfa_register $r11
BL @value, csr_aapcs, implicit-def dead $lr, implicit $sp, implicit-def $sp, implicit-def $r0, debug-location !25
DBG_VALUE $r0, $noreg, !24, !DIExpression(), debug-location !26
$sp = LDMIA_UPD $sp, 14, $noreg, def $r11, def $lr, debug-location !27
TAILJMPd @callee, implicit $sp, implicit $sp, implicit killed $r0, debug-location !27
...
---
name: callee
tracksRegLiveness: true
stack:
- { id: 0, name: '', type: spill-slot, offset: -4, size: 4, alignment: 4,
stack-id: default, callee-saved-register: '$lr', callee-saved-restored: true,
debug-info-variable: '', debug-info-expression: '', debug-info-location: '' }
- { id: 1, name: '', type: spill-slot, offset: -8, size: 4, alignment: 4,
stack-id: default, callee-saved-register: '$r11', callee-saved-restored: true,
debug-info-variable: '', debug-info-expression: '', debug-info-location: '' }
- { id: 2, name: '', type: spill-slot, offset: -12, size: 4, alignment: 4,
stack-id: default, callee-saved-register: '$r10', callee-saved-restored: true,
debug-info-variable: '', debug-info-expression: '', debug-info-location: '' }
- { id: 3, name: '', type: spill-slot, offset: -16, size: 4, alignment: 4,
stack-id: default, callee-saved-register: '$r4', callee-saved-restored: true,
debug-info-variable: '', debug-info-expression: '', debug-info-location: '' }
body: |
bb.0:
successors: %bb.2(0x30000000), %bb.1(0x50000000)
liveins: $r0, $r4, $r10, $lr
DBG_VALUE $r0, $noreg, !33, !DIExpression(), debug-location !35
$sp = frame-setup STMDB_UPD $sp, 14, $noreg, killed $r4, killed $r10, $r11, killed $lr
frame-setup CFI_INSTRUCTION def_cfa_offset 16
frame-setup CFI_INSTRUCTION offset $lr, -4
frame-setup CFI_INSTRUCTION offset $r11, -8
frame-setup CFI_INSTRUCTION offset $r10, -12
frame-setup CFI_INSTRUCTION offset $r4, -16
$r11 = frame-setup ADDri $sp, 8, 14, $noreg, $noreg
frame-setup CFI_INSTRUCTION def_cfa $r11, 8
$r4 = MOVr killed $r0, 14, $noreg, $noreg
DBG_VALUE $r4, $noreg, !33, !DIExpression(), debug-location !35
$r0 = MOVi 205, 14, $noreg, $noreg
$r0 = ORRri killed $r0, 43776, 14, $noreg, $noreg
; The MOVI and ORRri produce the second parameter's (!34) value which has
; been propagated from caller().
DBG_VALUE $r0, $noreg, !34, !DIExpression(), debug-location !35
BL @interesting, csr_aapcs, implicit-def dead $lr, implicit $sp, implicit killed $r0, implicit-def $sp, implicit-def $r0, debug-location !36
CMPri killed renamable $r0, 0, 14, $noreg, implicit-def $cpsr, debug-location !38
Bcc %bb.2, 0, killed $cpsr, debug-location !38
bb.1:
liveins: $r4
$r0 = MOVr $r4, 14, $noreg, $noreg, debug-location !41
BL @ext, csr_aapcs, implicit-def dead $lr, implicit $sp, implicit killed $r0, implicit-def $sp, debug-location !41
B %bb.1, debug-location !43
bb.2:
$r0 = MOVi 205, 14, $noreg, $noreg
$r0 = ORRri killed $r0, 43776, 14, $noreg, $noreg
$sp = LDMIA_UPD $sp, 14, $noreg, def $r4, def $r10, def $r11, def $lr, debug-location !46
TAILJMPd @ext, implicit $sp, implicit $sp, implicit killed $r0, debug-location !46
...
# In this test case the second parameter's value has been propagated from the
# caller to the callee, so we should not emit any entry value DBG_VALUEs for
# that parameter. The second parameter reuses the first parameter's register
# ($r0), and previously we would incorrectly emit an entry value for the
# parameter using that register.
# CHECK-DAG: ![[P1:[0-9]+]] = !DILocalVariable(name: "p1", arg: 1
# CHECK-DAG: ![[P2:[0-9]+]] = !DILocalVariable(name: "p2", arg: 2
# CHECK-NOT: DBG_VALUE $r0, $noreg, ![[P2]], !DIExpression(DW_OP_LLVM_entry_value
# CHECK: DBG_VALUE $r0, $noreg, ![[P1]], !DIExpression(DW_OP_LLVM_entry_value
# CHECK-NOT: DBG_VALUE $r0, $noreg, ![[P2]], !DIExpression(DW_OP_LLVM_entry_value
|
