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| # RUN: llc -mtriple=x86_64-unknown-unknown -run-pass=machine-sink -o - %s | FileCheck %s
# Check various things when we sink machine instructions:
# a) DBG_VALUEs should sink with defs
# b) Undefs should be left behind
# c) DBG_VALUEs not immediately following the defining inst should sink too
# d) If we generate debug-use-before-defs through sinking, and can copy
# propagate to a different value, we should do that.
--- |
target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-unknown-linux-gnu"
@x = common local_unnamed_addr global i32 0, align 4, !dbg !0
; Function Attrs: noreturn nounwind uwtable
define void @Process(i32* nocapture readonly %p) local_unnamed_addr !dbg !9 {
; Stripped
entry:
br label %nou
nou:
br label %exit
exit:
ret void
}
; Function Attrs: nounwind readnone
declare void @llvm.dbg.value(metadata, i64, metadata, metadata)
!llvm.dbg.cu = !{!1}
!llvm.module.flags = !{!6, !7}
!llvm.ident = !{!8}
!0 = !DIGlobalVariableExpression(var: !DIGlobalVariable(name: "x", scope: !1, file: !2, line: 1, type: !5, isLocal: false, isDefinition: true), expr: !DIExpression())
!1 = distinct !DICompileUnit(language: DW_LANG_C99, file: !2, producer: "clang", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !3, globals: !4)
!2 = !DIFile(filename: "t.c", directory: "")
!3 = !{}
!4 = !{!0}
!5 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
!6 = !{i32 2, !"Dwarf Version", i32 4}
!7 = !{i32 2, !"Debug Info Version", i32 3}
!8 = !{!"clang version 4.0.0 "}
!9 = distinct !DISubprogram(name: "Process", scope: !2, file: !2, line: 2, type: !10, isLocal: false, isDefinition: true, scopeLine: 3, flags: DIFlagPrototyped, isOptimized: true, unit: !1, retainedNodes: !15)
!10 = !DISubroutineType(types: !11)
!11 = !{null, !12}
!12 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !13, size: 64)
!13 = !DIDerivedType(tag: DW_TAG_const_type, baseType: !14)
!14 = !DIBasicType(name: "unsigned int", size: 32, encoding: DW_ATE_unsigned)
!15 = !{!16}
!16 = !DILocalVariable(name: "p", arg: 1, scope: !9, file: !2, line: 2, type: !12)
!17 = !DIExpression()
!18 = !DILocation(line: 2, column: 34, scope: !9)
!28 = !DILexicalBlockFile(scope: !9, file: !2, discriminator: 1)
; CHECK: [[VARNUM:![0-9]+]] = !DILocalVariable(name: "p",
...
---
name: Process
tracksRegLiveness: true
liveins:
- { reg: '$rdi', virtual-reg: '%2' }
- { reg: '$rsi', virtual-reg: '%2' }
body: |
bb.0.entry:
successors: %bb.1.nou(0x80000000), %bb.2.exit
liveins: $rdi, $esi
; This block should have the vreg copy sunk from it, the DBG_VALUE with it,
; and a copy-prop'd DBG_VALUE left over.
; CHECK-LABEL: bb.0.entry:
; CHECK: [[ARG0VREG:%[0-9]+]]:gr64 = COPY $rdi
; CHECK-NEXT: CMP32ri $esi, 0
; CHECK-NEXT: DBG_VALUE [[ARG0VREG]], $noreg, [[VARNUM]]
; CHECK-NEXT: JCC_1 %bb.1, 4
; CHECK-NEXT: JMP_1
%2:gr64 = COPY $rdi
%5:gr64 = COPY %2
CMP32ri $esi, 0, implicit-def $eflags
DBG_VALUE %5, $noreg, !16, !17, debug-location !18
JCC_1 %bb.1.nou, 4, implicit $eflags
JMP_1 %bb.2.exit
bb.1.nou:
successors: %bb.2.exit(0x80000000)
; This block should receive the sunk copy and DBG_VALUE
; CHECK-LABEL: bb.1.nou:
; CHECK: [[SUNKVREG:%[0-9]+]]:gr64 = COPY [[ARG0VREG]]
; CHECK-NEXT: DBG_VALUE [[SUNKVREG]], $noreg, [[VARNUM]]
; CHECK-NEXT: ADD64ri8
; CHECK-NEXT: JMP_1
%1:gr64 = ADD64ri8 %5, 4, implicit-def dead $eflags
JMP_1 %bb.2.exit
bb.2.exit:
; The DBG_VALUE below should have its operand copy-propagated after
; the copy to %5 is sunk.
; CHECK-LABEL: bb.2.exit:
; CHECK: DBG_VALUE [[ARG0VREG]], $noreg, [[VARNUM]]
; CHECK-NEXT: $rax = MOV64rr [[ARG0VREG]]
; CHECK-NEXT: RET 0
DBG_VALUE %5, _, !16, !17, debug-location !18
$rax = MOV64rr %2
RET 0
...
|