third_party/llvm-7.0/llvm/test/CodeGen/X86/peephole.mir

# RUN: llc -mtriple=x86_64-- -run-pass=peephole-opt %s -o - | FileCheck %s
--- |
  define void @func() { ret void }
...
---
# Check that instructions with MI.isBitcast() are only replaced by COPY if there
# are no SUBREG_TO_REG users.
# CHECK-LABEL: name: func
name: func
registers:
  - { id: 0, class: gr32 }
  - { id: 1, class: fr32 }
  - { id: 2, class: gr32 }

  - { id: 3, class: gr32 }
  - { id: 4, class: fr32 }
  - { id: 5, class: gr32 }
  - { id: 6, class: gr64 }

body: |
  bb.0:
    ; CHECK: %1:fr32 = VMOVDI2SSrr %0
    ; CHECK: %7:gr32 = COPY %0
    ; CHECK: NOOP implicit %7
    %0 = MOV32ri 42
    %1 = VMOVDI2SSrr %0
    %2 = MOVSS2DIrr %1
    NOOP implicit %2

    ; CHECK: %4:fr32 = VMOVDI2SSrr %3
    ; CHECK-NOT: COPY
    ; CHECK: %5:gr32 = MOVSS2DIrr %4
    ; CHECK: %6:gr64 = SUBREG_TO_REG %5, 0
    ; CHECK: NOOP implicit %6
    %3 = MOV32ri 42
    %4 = VMOVDI2SSrr %3
    %5 = MOVSS2DIrr %4
    %6 = SUBREG_TO_REG %5, 0, %subreg.sub_32bit
    NOOP implicit %6
...