pr38952.mir 3.39 KB
# RUN: llc %s -run-pass=postra-machine-sink -o - | FileCheck %s
--- |
  ; Module stripped of everything, MIR below is what's interesting
  ; ModuleID = '<stdin>'
  source_filename = "justacall.cpp"
  target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
  target triple = "x86_64-unknown-linux-gnu"
  
  ; Function Attrs: noinline norecurse nounwind uwtable
  define dso_local i32 @main(i32 %argc, i8** nocapture readnone %argv) local_unnamed_addr #0 {
  entry:
    br label %if.end
  if.end:
    br label %return
  return:
    ret i32 0
  }

  !0 = !{!"dummy metadata"}
  !2 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, file: !3, producer: "clang", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !4, globals: !5, nameTableKind: None)
  !3 = !DIFile(filename: "justacall.cpp", directory: "/tmp")
  !4 = !{}
  !5 = !{!0}
  !7 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
  !14 = distinct !DISubprogram(name: "main", scope: !3, file: !3, line: 7, type: !15, isLocal: false, isDefinition: true, scopeLine: 8, flags: DIFlagPrototyped, isOptimized: true, unit: !2, retainedNodes: !20)
  !15 = !DISubroutineType(types: !16)
  !16 = !{!7, !7}
  !20 = !{!21}
  !21 = !DILocalVariable(name: "argc", arg: 1, scope: !14, file: !3, line: 7, type: !7)

...
---
name:            main
alignment:       16
exposesReturnsTwice: false
legalized:       false
regBankSelected: false
selected:        false
failedISel:      false
tracksRegLiveness: true
hasWinCFI:       false
registers:
liveins:
  - { reg: '$edi', virtual-reg: '' }
frameInfo:
  isFrameAddressTaken: false
  isReturnAddressTaken: false
  hasStackMap:     false
  hasPatchPoint:   false
  stackSize:       0
  offsetAdjustment: 0
  maxAlignment:    0
  adjustsStack:    false
  hasCalls:        true
  stackProtector:  ''
  maxCallFrameSize: 4294967295
  cvBytesOfCalleeSavedRegisters: 0
  hasOpaqueSPAdjustment: false
  hasVAStart:      false
  hasMustTailInVarArgFunc: false
  localFrameSize:  0
  savePoint:       ''
  restorePoint:    ''
fixedStack:
stack:
constants:
body:             |
  bb.0.entry:
    successors: %bb.2(0x40000000), %bb.1(0x40000000)
    liveins: $edi
  
  ; Test that the DBG_VALUE on ebx below is sunk with the def of ebx, despite
  ; not being adjacent to the def, see PR38952

    DBG_VALUE $edi, $noreg, !21, !DIExpression()
    renamable $ebx = COPY $edi
    renamable $eax = MOV32r0 implicit-def dead $eflags
    DBG_VALUE $ebx, $noreg, !21, !DIExpression()
    CMP32ri $edi, 255, implicit-def $eflags
    JCC_1 %bb.2, 15, implicit killed $eflags
    JMP_1 %bb.1
  
  bb.1.if.end:
  ; CHECK-LABEL: bb.1.if.end
    successors: %bb.2(0x80000000)
    liveins: $ebx
  
  ; CHECK: $ebx = COPY $edi
  ; CHECK-NEXT: DBG_VALUE $ebx
    renamable $rdx = MOVSX64rr32 renamable $ebx
    renamable $rdx = nsw SHL64ri killed renamable $rdx, 2, implicit-def dead $eflags
    ADJCALLSTACKDOWN64 0, 0, 0, implicit-def dead $rsp, implicit-def dead $eflags, implicit-def dead $ssp, implicit $rsp, implicit $ssp
    $rdi = MOV32ri64 0
    $esi = MOV32r0 implicit-def dead $eflags
    CALL64pcrel32 &memset, csr_64, implicit $rsp, implicit $ssp, implicit $rdi, implicit killed $esi, implicit $rdx, implicit-def $rsp, implicit-def $ssp, implicit-def dead $rax
    ADJCALLSTACKUP64 0, 0, implicit-def dead $rsp, implicit-def dead $eflags, implicit-def dead $ssp, implicit $rsp, implicit $ssp
  
  bb.2.return:
    liveins: $eax
  
    RET 0, $eax

...