limit-split-cost.mir 6.49 KB
# REQUIRES: asserts
# RUN: llc -mtriple=x86_64-- -run-pass=greedy %s -debug-only=regalloc -huge-size-for-split=0 -o /dev/null 2>&1 | FileCheck %s
# Check no global region split is needed because the live range to split is trivially rematerializable.
# CHECK-NOT: Compact region bundles
--- |
  ; ModuleID = '<stdin>'
  source_filename = "2.cc"
  target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
  target triple = "x86_64-unknown-linux-gnu"
  
  @m = local_unnamed_addr global i32 0, align 4
  @.str = private unnamed_addr constant [4 x i8] c"abc\00", align 1
  @.str.1 = private unnamed_addr constant [4 x i8] c"def\00", align 1
  @.str.2 = private unnamed_addr constant [4 x i8] c"ghi\00", align 1
  
  ; Function Attrs: uwtable
  define void @_Z3fooi(i32 %value) local_unnamed_addr #0 {
  entry:
    br label %do.body
  
  do.body:                                          ; preds = %do.cond, %entry
    tail call void asm sideeffect "", "~{r10},~{r11},~{r12},~{r13},~{r14},~{r15},~{dirflag},~{fpsr},~{flags}"() #2, !srcloc !3
    switch i32 %value, label %do.cond [
      i32 0, label %sw.bb
      i32 1, label %sw.bb1
      i32 2, label %sw.bb2
    ]
  
  sw.bb:                                            ; preds = %do.body
    tail call void @_Z3gooPKc(i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str, i64 0, i64 0))
    br label %sw.bb1
  
  sw.bb1:                                           ; preds = %sw.bb, %do.body
    tail call void @_Z3gooPKc(i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str.1, i64 0, i64 0))
    br label %sw.bb2
  
  sw.bb2:                                           ; preds = %sw.bb1, %do.body
    tail call void @_Z3gooPKc(i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str.2, i64 0, i64 0))
    br label %do.cond
  
  do.cond:                                          ; preds = %sw.bb2, %do.body
    %0 = load i32, i32* @m, align 4, !tbaa !4
    %cmp = icmp eq i32 %0, 5
    br i1 %cmp, label %do.end, label %do.body
  
  do.end:                                           ; preds = %do.cond
    ret void
  }
  
  declare void @_Z3gooPKc(i8*) local_unnamed_addr #1
  
  ; Function Attrs: nounwind
  declare void @llvm.stackprotector(i8*, i8**) #2
  
  attributes #0 = { uwtable "correctly-rounded-divide-sqrt-fp-math"="false" "disable-tail-calls"="false" "less-precise-fpmad"="false" "frame-pointer"="none" "no-infs-fp-math"="false" "no-jump-tables"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="false" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+fxsr,+mmx,+sse,+sse2,+x87" "unsafe-fp-math"="false" "use-soft-float"="false" }
  attributes #1 = { "correctly-rounded-divide-sqrt-fp-math"="false" "disable-tail-calls"="false" "less-precise-fpmad"="false" "frame-pointer"="none" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="false" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+fxsr,+mmx,+sse,+sse2,+x87" "unsafe-fp-math"="false" "use-soft-float"="false" }
  attributes #2 = { nounwind }
  
  !llvm.module.flags = !{!0, !1}
  !llvm.ident = !{!2}
  
  !0 = !{i32 1, !"wchar_size", i32 4}
  !1 = !{i32 7, !"PIC Level", i32 2}
  !2 = !{!"clang version 7.0.0 (trunk 335057)"}
  !3 = !{i32 80}
  !4 = !{!5, !5, i64 0}
  !5 = !{!"int", !6, i64 0}
  !6 = !{!"omnipotent char", !7, i64 0}
  !7 = !{!"Simple C++ TBAA"}

...
---
name:            _Z3fooi
alignment:       16
tracksRegLiveness: true
registers:       
  - { id: 0, class: gr32 }
  - { id: 1, class: gr32 }
  - { id: 2, class: gr32 }
  - { id: 3, class: gr64 }
  - { id: 4, class: gr64 }
  - { id: 5, class: gr64 }
  - { id: 6, class: gr64 }
  - { id: 7, class: gr32 }
  - { id: 8, class: gr32 }
liveins:         
  - { reg: '$edi', virtual-reg: '%0' }
frameInfo:       
  hasCalls:        true
body:             |
  bb.0.entry:
    liveins: $edi
  
    %0:gr32 = COPY $edi
    %5:gr64 = LEA64r $rip, 1, $noreg, @.str.2, $noreg
    %6:gr64 = MOV64rm $rip, 1, $noreg, target-flags(x86-gotpcrel) @m, $noreg :: (load 8 from got)
    %4:gr64 = LEA64r $rip, 1, $noreg, @.str.1, $noreg
    %3:gr64 = LEA64r $rip, 1, $noreg, @.str, $noreg
  
  bb.1.do.body:
    successors: %bb.6(0x20000000), %bb.2(0x60000000)
  
    INLINEASM &"", 1, 12, implicit-def dead early-clobber $r10, 12, implicit-def dead early-clobber $r11, 12, implicit-def dead early-clobber $r12, 12, implicit-def dead early-clobber $r13, 12, implicit-def dead early-clobber $r14, 12, implicit-def dead early-clobber $r15, 12, implicit-def dead early-clobber $eflags, !3
    CMP32ri8 %0, 2, implicit-def $eflags
    JCC_1 %bb.6, 4, implicit killed $eflags
    JMP_1 %bb.2
  
  bb.2.do.body:
    successors: %bb.5(0x2aaaaaab), %bb.3(0x55555555)
  
    CMP32ri8 %0, 1, implicit-def $eflags
    JCC_1 %bb.5, 4, implicit killed $eflags
    JMP_1 %bb.3
  
  bb.3.do.body:
    successors: %bb.4, %bb.7
  
    TEST32rr %0, %0, implicit-def $eflags
    JCC_1 %bb.7, 5, implicit killed $eflags
    JMP_1 %bb.4
  
  bb.4.sw.bb:
    ADJCALLSTACKDOWN64 0, 0, 0, implicit-def dead $rsp, implicit-def dead $eflags, implicit-def dead $ssp, implicit $rsp, implicit $ssp
    $rdi = COPY %3
    CALL64pcrel32 target-flags(x86-plt) @_Z3gooPKc, csr_64, implicit $rsp, implicit $ssp, implicit $rdi, implicit-def $rsp, implicit-def $ssp
    ADJCALLSTACKUP64 0, 0, implicit-def dead $rsp, implicit-def dead $eflags, implicit-def dead $ssp, implicit $rsp, implicit $ssp
  
  bb.5.sw.bb1:
    ADJCALLSTACKDOWN64 0, 0, 0, implicit-def dead $rsp, implicit-def dead $eflags, implicit-def dead $ssp, implicit $rsp, implicit $ssp
    $rdi = COPY %4
    CALL64pcrel32 target-flags(x86-plt) @_Z3gooPKc, csr_64, implicit $rsp, implicit $ssp, implicit $rdi, implicit-def $rsp, implicit-def $ssp
    ADJCALLSTACKUP64 0, 0, implicit-def dead $rsp, implicit-def dead $eflags, implicit-def dead $ssp, implicit $rsp, implicit $ssp
  
  bb.6.sw.bb2:
    ADJCALLSTACKDOWN64 0, 0, 0, implicit-def dead $rsp, implicit-def dead $eflags, implicit-def dead $ssp, implicit $rsp, implicit $ssp
    $rdi = COPY %5
    CALL64pcrel32 target-flags(x86-plt) @_Z3gooPKc, csr_64, implicit $rsp, implicit $ssp, implicit $rdi, implicit-def $rsp, implicit-def $ssp
    ADJCALLSTACKUP64 0, 0, implicit-def dead $rsp, implicit-def dead $eflags, implicit-def dead $ssp, implicit $rsp, implicit $ssp
  
  bb.7.do.cond:
    successors: %bb.8(0x04000000), %bb.1(0x7c000000)
  
    CMP32mi8 %6, 1, $noreg, 0, $noreg, 5, implicit-def $eflags :: (dereferenceable load 4 from @m, !tbaa !4)
    JCC_1 %bb.1, 5, implicit killed $eflags
    JMP_1 %bb.8
  
  bb.8.do.end:
    RET 0

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