tail-call-conditional.mir 2.36 KB
# RUN: llc -mtriple x86_64-- -verify-machineinstrs -run-pass branch-folder -o - %s | FileCheck %s

# Check the TCRETURNdi64cc optimization.

--- |
  target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"

  define i64 @test(i64 %arg, i8* %arg1) optsize {
    %tmp = icmp ult i64 %arg, 100
    br i1 %tmp, label %1, label %4

    %tmp3 = icmp ult i64 %arg, 10
    br i1 %tmp3, label %2, label %3

    %tmp5 = tail call i64 @f1(i8* %arg1, i64 %arg)
    ret i64 %tmp5

    %tmp7 = tail call i64 @f2(i8* %arg1, i64 %arg)
    ret i64 %tmp7

    ret i64 123
  }

  declare i64 @f1(i8*, i64)
  declare i64 @f2(i8*, i64)

...
---
name: test
tracksRegLiveness: true
liveins:
  - { reg: '$rdi' }
  - { reg: '$rsi' }
body:             |
  bb.0:
    successors: %bb.1, %bb.4
    liveins: $rdi, $rsi

    $rax = COPY $rdi
    CMP64ri8 $rax, 99, implicit-def $eflags
    JCC_1 %bb.4, 7, implicit $eflags
    JMP_1 %bb.1

  ; CHECK: bb.1:
  ; CHECK-NEXT: successors: %bb.2({{[^)]+}}){{$}}
  ; CHECK-NEXT: liveins: $rax, $rsi
  ; CHECK-NEXT: {{^  $}}
  ; CHECK-NEXT: $rdi = COPY $rsi
  ; CHECK-NEXT: $rsi = COPY $rax
  ; CHECK-NEXT: CMP64ri8 $rax, 9, implicit-def $eflags
  ; CHECK-NEXT: TCRETURNdi64cc @f1, 0, 6, csr_64, implicit $rsp, implicit $eflags, implicit $ssp, implicit $rsp, implicit $rdi, implicit $rsi, implicit $rdi, implicit-def $rdi, implicit $hsi, implicit-def $hsi, implicit $sih, implicit-def $sih, implicit $sil, implicit-def $sil, implicit $si, implicit-def $si, implicit $esi, implicit-def $esi, implicit $rsi, implicit-def $rsi, implicit $hdi, implicit-def $hdi, implicit $dih, implicit-def $dih, implicit $dil, implicit-def $dil, implicit $di, implicit-def $di, implicit $edi, implicit-def $edi

  bb.1:
    successors: %bb.2, %bb.3
    liveins: $rax, $rsi

    CMP64ri8 $rax, 9, implicit-def $eflags
    JCC_1 %bb.3, 7, implicit $eflags
    JMP_1 %bb.2

  bb.2:
    liveins: $rax, $rsi

    $rdi = COPY $rsi
    $rsi = COPY $rax

    TCRETURNdi64 @f1, 0, csr_64, implicit $rsp, implicit $rdi, implicit $rsi

  ; CHECK: bb.2:
  ; CHECK-NEXT: liveins: $rdi, $rsi
  ; CHECK-NEXT: {{^  $}}
  ; CHECK-NEXT: TCRETURNdi64 @f2, 0, csr_64, implicit $rsp, implicit $rdi, implicit $rsi

  bb.3:
    liveins: $rax, $rsi

    $rdi = COPY $rsi
    $rsi = COPY $rax
    TCRETURNdi64 @f2, 0, csr_64, implicit $rsp, implicit $rdi, implicit $rsi

  bb.4:
    dead $eax = MOV32ri 123, implicit-def $rax
    RET 0, $rax

...