# RUN: llc -march=amdgcn -verify-machineinstrs -run-pass si-optimize-exec-masking -o -  %s | FileCheck %s

--- |
  define amdgpu_kernel void @optimize_if_and_saveexec_xor(i32 %z, i32 %v) {
  main_body:
    br i1 undef, label %if, label %end

  if:                                               ; preds = %main_body
    %v.if = load volatile i32, i32 addrspace(1)* undef
    br label %end

  end:                                              ; preds = %if, %main_body
    ret void
  }

  define amdgpu_kernel void @optimize_if_and_saveexec(i32 %z, i32 %v) {
  main_body:
    br i1 undef, label %if, label %end

  if:
    br label %end

  end:
    ret void
  }

  define amdgpu_kernel void @optimize_if_or_saveexec(i32 %z, i32 %v) {
  main_body:
    br i1 undef, label %if, label %end

  if:
    br label %end

  end:
    ret void
  }

  define amdgpu_kernel void @optimize_if_and_saveexec_xor_valu_middle(i32 %z, i32 %v) {
  main_body:
    br i1 undef, label %if, label %end

  if:                                               ; preds = %main_body
    br label %end

  end:                                              ; preds = %if, %main_body
    ret void
  }

  define amdgpu_kernel void @optimize_if_and_saveexec_xor_wrong_reg(i32 %z, i32 %v) {
  main_body:
    br i1 undef, label %if, label %end

  if:
    br label %end

  end:
    ret void
  }

  define amdgpu_kernel void @optimize_if_and_saveexec_xor_modify_copy_to_exec(i32 %z, i32 %v) {
  main_body:
    br i1 undef, label %if, label %end

  if:
    br label %end

  end:
    ret void
  }

  define amdgpu_kernel void @optimize_if_and_saveexec_xor_live_out_setexec(i32 %z, i32 %v) {
  main_body:
    br i1 undef, label %if, label %end

  if:
    br label %end

  end:
    ret void
  }

  define amdgpu_kernel void @optimize_if_unknown_saveexec(i32 %z, i32 %v) {
  main_body:
    br i1 undef, label %if, label %end

  if:
    br label %end

  end:
    ret void
  }

  define amdgpu_kernel void @optimize_if_andn2_saveexec(i32 %z, i32 %v) {
  main_body:
    br i1 undef, label %if, label %end

  if:
    br label %end

  end:
    ret void
  }

  define amdgpu_kernel void @optimize_if_andn2_saveexec_no_commute(i32 %z, i32 %v) {
  main_body:
    br i1 undef, label %if, label %end

  if:
    br label %end

  end:
    ret void
  }

  define amdgpu_kernel void @if_and_xor_read_exec_copy_subreg() {
  main_body:
    br i1 undef, label %if, label %end

  if:                                               ; preds = %main_body
    br label %end

  end:                                              ; preds = %if, %main_body
    ret void
  }

...
---
# CHECK-LABEL: name: optimize_if_and_saveexec_xor{{$}}
# CHECK: $sgpr0_sgpr1 = S_AND_SAVEEXEC_B64 $vcc, implicit-def $exec, implicit-def $scc, implicit $exec
# CHECK-NEXT: $sgpr0_sgpr1 = S_XOR_B64 $exec, killed $sgpr0_sgpr1, implicit-def $scc
# CHECK-NEXT: SI_MASK_BRANCH

name:            optimize_if_and_saveexec_xor
liveins:
  - { reg: '$vgpr0' }
body:             |
  bb.0.main_body:
    liveins: $vgpr0

    $sgpr0_sgpr1 = COPY $exec
    $vcc = V_CMP_EQ_I32_e64 0, killed $vgpr0, implicit $exec
    $vgpr0 = V_MOV_B32_e32 4, implicit $exec
    $sgpr2_sgpr3 = S_AND_B64 $sgpr0_sgpr1, killed $vcc, implicit-def $scc
    $sgpr0_sgpr1 = S_XOR_B64 $sgpr2_sgpr3, killed $sgpr0_sgpr1, implicit-def $scc
    $exec = S_MOV_B64_term killed $sgpr2_sgpr3
    SI_MASK_BRANCH %bb.2, implicit $exec
    S_BRANCH %bb.1

  bb.1.if:
    liveins: $sgpr0_sgpr1

    $sgpr7 = S_MOV_B32 61440
    $sgpr6 = S_MOV_B32 -1
    $vgpr0 = BUFFER_LOAD_DWORD_OFFSET $sgpr4_sgpr5_sgpr6_sgpr7, 0, 0, 0, 0, 0, 0, 0, 0, implicit $exec

  bb.2.end:
    liveins: $vgpr0, $sgpr0_sgpr1

    $exec = S_OR_B64 $exec, killed $sgpr0_sgpr1, implicit-def $scc
    $sgpr3 = S_MOV_B32 61440
    $sgpr2 = S_MOV_B32 -1
    BUFFER_STORE_DWORD_OFFSET killed $vgpr0, $sgpr0_sgpr1_sgpr2_sgpr3, 0, 0, 0, 0, 0, 0, 0, 0, implicit $exec
    S_ENDPGM 0

...
---
# CHECK-LABEL: name: optimize_if_and_saveexec{{$}}
# CHECK: $sgpr0_sgpr1 = S_AND_SAVEEXEC_B64 $vcc, implicit-def $exec, implicit-def $scc, implicit $exec
# CHECK-NEXT: SI_MASK_BRANCH

name:            optimize_if_and_saveexec
liveins:
  - { reg: '$vgpr0' }
body:             |
  bb.0.main_body:
    liveins: $vgpr0

    $sgpr0_sgpr1 = COPY $exec
    $vcc = V_CMP_EQ_I32_e64 0, killed $vgpr0, implicit $exec
    $vgpr0 = V_MOV_B32_e32 4, implicit $exec
    $sgpr2_sgpr3 = S_AND_B64 $sgpr0_sgpr1, killed $vcc, implicit-def $scc
    $exec = S_MOV_B64_term killed $sgpr2_sgpr3
    SI_MASK_BRANCH %bb.2, implicit $exec
    S_BRANCH %bb.1

  bb.1.if:
    liveins: $sgpr0_sgpr1

    $sgpr7 = S_MOV_B32 61440
    $sgpr6 = S_MOV_B32 -1
    $vgpr0 = BUFFER_LOAD_DWORD_OFFSET $sgpr4_sgpr5_sgpr6_sgpr7, 0, 0, 0, 0, 0, 0, 0, 0, implicit $exec

  bb.2.end:
    liveins: $vgpr0, $sgpr0_sgpr1

    $exec = S_OR_B64 $exec, killed $sgpr0_sgpr1, implicit-def $scc
    $sgpr3 = S_MOV_B32 61440
    $sgpr2 = S_MOV_B32 -1
    BUFFER_STORE_DWORD_OFFSET killed $vgpr0, $sgpr0_sgpr1_sgpr2_sgpr3, 0, 0, 0, 0, 0, 0, 0, 0, implicit $exec
    S_ENDPGM 0

...
---
# CHECK-LABEL: name: optimize_if_or_saveexec{{$}}
# CHECK: $sgpr0_sgpr1 = S_OR_SAVEEXEC_B64 $vcc, implicit-def $exec, implicit-def $scc, implicit $exec
# CHECK-NEXT: SI_MASK_BRANCH

name:            optimize_if_or_saveexec
liveins:
  - { reg: '$vgpr0' }
body:             |
  bb.0.main_body:
    liveins: $vgpr0

    $sgpr0_sgpr1 = COPY $exec
    $vcc = V_CMP_EQ_I32_e64 0, killed $vgpr0, implicit $exec
    $vgpr0 = V_MOV_B32_e32 4, implicit $exec
    $sgpr2_sgpr3 = S_OR_B64 $sgpr0_sgpr1, killed $vcc, implicit-def $scc
    $exec = S_MOV_B64_term killed $sgpr2_sgpr3
    SI_MASK_BRANCH %bb.2, implicit $exec
    S_BRANCH %bb.1

  bb.1.if:
    liveins: $sgpr0_sgpr1

    $sgpr7 = S_MOV_B32 61440
    $sgpr6 = S_MOV_B32 -1
    $vgpr0 = BUFFER_LOAD_DWORD_OFFSET $sgpr4_sgpr5_sgpr6_sgpr7, 0, 0, 0, 0, 0, 0, 0, 0, implicit $exec

  bb.2.end:
    liveins: $vgpr0, $sgpr0_sgpr1

    $exec = S_OR_B64 $exec, killed $sgpr0_sgpr1, implicit-def $scc
    $sgpr3 = S_MOV_B32 61440
    $sgpr2 = S_MOV_B32 -1
    BUFFER_STORE_DWORD_OFFSET killed $vgpr0, $sgpr0_sgpr1_sgpr2_sgpr3, 0, 0, 0, 0, 0, 0, 0, 0, implicit $exec
    S_ENDPGM 0

...
---
# CHECK-LABEL: name: optimize_if_and_saveexec_xor_valu_middle
# CHECK: $sgpr2_sgpr3 = S_AND_B64 $sgpr0_sgpr1, killed $vcc, implicit-def $scc
# CHECK-NEXT: BUFFER_STORE_DWORD_OFFSET $vgpr0, undef $sgpr0_sgpr1_sgpr2_sgpr3, 0, 0, 0, 0, 0, 0, 0, 0, implicit $exec
# CHECK-NEXT: $sgpr0_sgpr1 = S_XOR_B64 $sgpr2_sgpr3, killed $sgpr0_sgpr1, implicit-def $scc
# CHECK-NEXT: $exec = COPY killed $sgpr2_sgpr3
# CHECK-NEXT: SI_MASK_BRANCH
name:            optimize_if_and_saveexec_xor_valu_middle
liveins:
  - { reg: '$vgpr0' }
body:             |
  bb.0.main_body:
    liveins: $vgpr0

    $sgpr0_sgpr1 = COPY $exec
    $vcc = V_CMP_EQ_I32_e64 0, killed $vgpr0, implicit $exec
    $vgpr0 = V_MOV_B32_e32 4, implicit $exec
    $sgpr2_sgpr3 = S_AND_B64 $sgpr0_sgpr1, killed $vcc, implicit-def $scc
    BUFFER_STORE_DWORD_OFFSET $vgpr0, undef $sgpr0_sgpr1_sgpr2_sgpr3, 0, 0, 0, 0, 0, 0, 0, 0, implicit $exec
    $sgpr0_sgpr1 = S_XOR_B64 $sgpr2_sgpr3, killed $sgpr0_sgpr1, implicit-def $scc
    $exec = S_MOV_B64_term killed $sgpr2_sgpr3
    SI_MASK_BRANCH %bb.2, implicit $exec
    S_BRANCH %bb.1

  bb.1.if:
    liveins: $sgpr0_sgpr1

    $sgpr7 = S_MOV_B32 61440
    $sgpr6 = S_MOV_B32 -1
    $vgpr0 = BUFFER_LOAD_DWORD_OFFSET $sgpr4_sgpr5_sgpr6_sgpr7, 0, 0, 0, 0, 0, 0, 0, 0, implicit $exec

  bb.2.end:
    liveins: $vgpr0, $sgpr0_sgpr1

    $exec = S_OR_B64 $exec, killed $sgpr0_sgpr1, implicit-def $scc
    $sgpr3 = S_MOV_B32 61440
    $sgpr2 = S_MOV_B32 -1
    BUFFER_STORE_DWORD_OFFSET killed $vgpr0, $sgpr0_sgpr1_sgpr2_sgpr3, 0, 0, 0, 0, 0, 0, 0, 0, implicit $exec
    S_ENDPGM 0

...
---
# CHECK-LABEL: name: optimize_if_and_saveexec_xor_wrong_reg{{$}}
# CHECK: $sgpr0_sgpr1 = S_AND_B64 $sgpr0_sgpr1, killed $vcc, implicit-def $scc
# CHECK-NEXT: $sgpr0_sgpr1 = S_XOR_B64 undef $sgpr2_sgpr3, killed $sgpr0_sgpr1, implicit-def $scc
# CHECK-NEXT: $exec = COPY $sgpr0_sgpr1
# CHECK-NEXT: SI_MASK_BRANCH %bb.2, implicit $exec
name:            optimize_if_and_saveexec_xor_wrong_reg
liveins:
  - { reg: '$vgpr0' }
body:             |
  bb.0.main_body:
    liveins: $vgpr0

    $sgpr6 = S_MOV_B32 -1
    $sgpr7 = S_MOV_B32 61440
    $sgpr0_sgpr1 = COPY $exec
    $vcc = V_CMP_EQ_I32_e64 0, killed $vgpr0, implicit $exec
    $vgpr0 = V_MOV_B32_e32 4, implicit $exec
    $sgpr0_sgpr1 = S_AND_B64 $sgpr0_sgpr1, killed $vcc, implicit-def $scc
    $sgpr0_sgpr1 = S_XOR_B64 undef $sgpr2_sgpr3, killed $sgpr0_sgpr1, implicit-def $scc
    $exec = S_MOV_B64_term $sgpr0_sgpr1
    SI_MASK_BRANCH %bb.2, implicit $exec
    S_BRANCH %bb.1

  bb.1.if:
    liveins: $sgpr0_sgpr1 , $sgpr4_sgpr5_sgpr6_sgpr7
    $vgpr0 = BUFFER_LOAD_DWORD_OFFSET $sgpr4_sgpr5_sgpr6_sgpr7, 0, 0, 0, 0, 0, 0, 0, 0, implicit $exec

  bb.2.end:
    liveins: $vgpr0, $sgpr0_sgpr1, $sgpr4_sgpr5_sgpr6_sgpr7

    $exec = S_OR_B64 $exec, killed $sgpr0_sgpr1, implicit-def $scc
    $sgpr3 = S_MOV_B32 61440
    $sgpr2 = S_MOV_B32 -1
    BUFFER_STORE_DWORD_OFFSET killed $vgpr0, $sgpr4_sgpr5_sgpr6_sgpr7, 0, 0, 0, 0, 0, 0, 0, 0, implicit $exec
    S_ENDPGM 0

...
---
# CHECK-LABEL: name: optimize_if_and_saveexec_xor_modify_copy_to_exec{{$}}
# CHECK: $sgpr2_sgpr3 = S_AND_B64 $sgpr0_sgpr1, killed $vcc, implicit-def $scc
# CHECK-NEXT: $sgpr2_sgpr3 = S_OR_B64 killed $sgpr2_sgpr3, 1, implicit-def $scc
# CHECK-NEXT: $sgpr0_sgpr1 = S_XOR_B64 $sgpr2_sgpr3, killed $sgpr0_sgpr1, implicit-def $scc
# CHECK-NEXT: $exec = COPY killed $sgpr2_sgpr3
# CHECK-NEXT: SI_MASK_BRANCH %bb.2, implicit $exec

name:            optimize_if_and_saveexec_xor_modify_copy_to_exec
liveins:
  - { reg: '$vgpr0' }
body:             |
  bb.0.main_body:
    liveins: $vgpr0

    $sgpr0_sgpr1 = COPY $exec
    $vcc = V_CMP_EQ_I32_e64 0, killed $vgpr0, implicit $exec
    $vgpr0 = V_MOV_B32_e32 4, implicit $exec
    $sgpr2_sgpr3 = S_AND_B64 $sgpr0_sgpr1, killed $vcc, implicit-def $scc
    $sgpr2_sgpr3 = S_OR_B64 killed $sgpr2_sgpr3, 1, implicit-def $scc
    $sgpr0_sgpr1 = S_XOR_B64 $sgpr2_sgpr3, killed $sgpr0_sgpr1, implicit-def $scc
    $exec = S_MOV_B64_term killed $sgpr2_sgpr3
    SI_MASK_BRANCH %bb.2, implicit $exec
    S_BRANCH %bb.1

  bb.1.if:
    liveins: $sgpr0_sgpr1

    $sgpr7 = S_MOV_B32 61440
    $sgpr6 = S_MOV_B32 -1
    $vgpr0 = BUFFER_LOAD_DWORD_OFFSET $sgpr4_sgpr5_sgpr6_sgpr7, 0, 0, 0, 0, 0, 0, 0, 0, implicit $exec

  bb.2.end:
    liveins: $vgpr0, $sgpr0_sgpr1

    $exec = S_OR_B64 $exec, killed $sgpr0_sgpr1, implicit-def $scc
    $sgpr0 = S_MOV_B32 0
    $sgpr1 = S_MOV_B32 1
    $sgpr2 = S_MOV_B32 -1
    $sgpr3 = S_MOV_B32 61440
    BUFFER_STORE_DWORD_OFFSET killed $vgpr0, $sgpr0_sgpr1_sgpr2_sgpr3, 0, 0, 0, 0, 0, 0, 0, 0, implicit $exec
    S_ENDPGM 0

...
---
# CHECK-LABEL: name: optimize_if_and_saveexec_xor_live_out_setexec{{$}}
# CHECK: $sgpr2_sgpr3 = S_AND_B64 $sgpr0_sgpr1, killed $vcc, implicit-def $scc
# CHECK-NEXT: $sgpr0_sgpr1 = S_XOR_B64 $sgpr2_sgpr3, killed $sgpr0_sgpr1, implicit-def $scc
# CHECK-NEXT: $exec = COPY $sgpr2_sgpr3
# CHECK-NEXT: SI_MASK_BRANCH
name:            optimize_if_and_saveexec_xor_live_out_setexec
liveins:
  - { reg: '$vgpr0' }
body:             |
  bb.0.main_body:
    liveins: $vgpr0

    $sgpr0_sgpr1 = COPY $exec
    $vcc = V_CMP_EQ_I32_e64 0, killed $vgpr0, implicit $exec
    $vgpr0 = V_MOV_B32_e32 4, implicit $exec
    $sgpr2_sgpr3 = S_AND_B64 $sgpr0_sgpr1, killed $vcc, implicit-def $scc
    $sgpr0_sgpr1 = S_XOR_B64 $sgpr2_sgpr3, killed $sgpr0_sgpr1, implicit-def $scc
    $exec = S_MOV_B64_term $sgpr2_sgpr3
    SI_MASK_BRANCH %bb.2, implicit $exec
    S_BRANCH %bb.1

  bb.1.if:
    liveins: $sgpr0_sgpr1, $sgpr2_sgpr3
    S_SLEEP 0, implicit $sgpr2_sgpr3
    $sgpr7 = S_MOV_B32 61440
    $sgpr6 = S_MOV_B32 -1
    $vgpr0 = BUFFER_LOAD_DWORD_OFFSET $sgpr4_sgpr5_sgpr6_sgpr7, 0, 0, 0, 0, 0, 0, 0, 0, implicit $exec

  bb.2.end:
    liveins: $vgpr0, $sgpr0_sgpr1

    $exec = S_OR_B64 $exec, killed $sgpr0_sgpr1, implicit-def $scc
    $sgpr3 = S_MOV_B32 61440
    $sgpr2 = S_MOV_B32 -1
    BUFFER_STORE_DWORD_OFFSET killed $vgpr0, $sgpr0_sgpr1_sgpr2_sgpr3, 0, 0, 0, 0, 0, 0, 0, 0, implicit $exec
    S_ENDPGM 0

...

# CHECK-LABEL: name: optimize_if_unknown_saveexec{{$}}
# CHECK: $sgpr0_sgpr1 = COPY $exec
# CHECK: $sgpr2_sgpr3 = S_LSHR_B64 $sgpr0_sgpr1, killed $vcc_lo, implicit-def $scc
# CHECK-NEXT: $exec = COPY killed $sgpr2_sgpr3
# CHECK-NEXT: SI_MASK_BRANCH %bb.2, implicit $exec

name:            optimize_if_unknown_saveexec
liveins:
  - { reg: '$vgpr0' }
body:             |
  bb.0.main_body:
    liveins: $vgpr0

    $sgpr0_sgpr1 = COPY $exec
    $vcc = V_CMP_EQ_I32_e64 0, killed $vgpr0, implicit $exec
    $vgpr0 = V_MOV_B32_e32 4, implicit $exec
    $sgpr2_sgpr3 = S_LSHR_B64 $sgpr0_sgpr1, killed $vcc_lo, implicit-def $scc
    $exec = S_MOV_B64_term killed $sgpr2_sgpr3
    SI_MASK_BRANCH %bb.2, implicit $exec
    S_BRANCH %bb.1

  bb.1.if:
    liveins: $sgpr0_sgpr1

    $sgpr7 = S_MOV_B32 61440
    $sgpr6 = S_MOV_B32 -1
    $vgpr0 = BUFFER_LOAD_DWORD_OFFSET $sgpr4_sgpr5_sgpr6_sgpr7, 0, 0, 0, 0, 0, 0, 0, 0, implicit $exec

  bb.2.end:
    liveins: $vgpr0, $sgpr0_sgpr1

    $exec = S_OR_B64 $exec, killed $sgpr0_sgpr1, implicit-def $scc
    $sgpr3 = S_MOV_B32 61440
    $sgpr2 = S_MOV_B32 -1
    BUFFER_STORE_DWORD_OFFSET killed $vgpr0, $sgpr0_sgpr1_sgpr2_sgpr3, 0, 0, 0, 0, 0, 0, 0, 0, implicit $exec
    S_ENDPGM 0

...
---
# CHECK-LABEL: name: optimize_if_andn2_saveexec{{$}}
# CHECK: $sgpr0_sgpr1 = S_ANDN2_SAVEEXEC_B64 $vcc, implicit-def $exec, implicit-def $scc, implicit $exec
# CHECK-NEXT: SI_MASK_BRANCH

name:            optimize_if_andn2_saveexec
liveins:
  - { reg: '$vgpr0' }
body:             |
  bb.0.main_body:
    liveins: $vgpr0

    $sgpr0_sgpr1 = COPY $exec
    $vcc = V_CMP_EQ_I32_e64 0, killed $vgpr0, implicit $exec
    $vgpr0 = V_MOV_B32_e32 4, implicit $exec
    $sgpr2_sgpr3 = S_ANDN2_B64 $sgpr0_sgpr1, killed $vcc, implicit-def $scc
    $exec = S_MOV_B64_term killed $sgpr2_sgpr3
    SI_MASK_BRANCH %bb.2, implicit $exec
    S_BRANCH %bb.1

  bb.1.if:
    liveins: $sgpr0_sgpr1

    $sgpr7 = S_MOV_B32 61440
    $sgpr6 = S_MOV_B32 -1
    $vgpr0 = BUFFER_LOAD_DWORD_OFFSET $sgpr4_sgpr5_sgpr6_sgpr7, 0, 0, 0, 0, 0, 0, 0, 0, implicit $exec

  bb.2.end:
    liveins: $vgpr0, $sgpr0_sgpr1

    $exec = S_OR_B64 $exec, killed $sgpr0_sgpr1, implicit-def $scc
    $sgpr3 = S_MOV_B32 61440
    $sgpr2 = S_MOV_B32 -1
    BUFFER_STORE_DWORD_OFFSET killed $vgpr0, $sgpr0_sgpr1_sgpr2_sgpr3, 0, 0, 0, 0, 0, 0, 0, 0, implicit $exec
    S_ENDPGM 0

...
---
# CHECK-LABEL: name: optimize_if_andn2_saveexec_no_commute{{$}}
# CHECK: $sgpr2_sgpr3 = S_ANDN2_B64 killed $vcc, $sgpr0_sgpr1, implicit-def $scc
# CHECK-NEXT: $exec = COPY killed $sgpr2_sgpr3
# CHECK-NEXT: SI_MASK_BRANCH %bb.2, implicit $exec
name:            optimize_if_andn2_saveexec_no_commute
liveins:
  - { reg: '$vgpr0' }
body:             |
  bb.0.main_body:
    liveins: $vgpr0

    $sgpr0_sgpr1 = COPY $exec
    $vcc = V_CMP_EQ_I32_e64 0, killed $vgpr0, implicit $exec
    $vgpr0 = V_MOV_B32_e32 4, implicit $exec
    $sgpr2_sgpr3 = S_ANDN2_B64 killed $vcc, $sgpr0_sgpr1, implicit-def $scc
    $exec = S_MOV_B64_term killed $sgpr2_sgpr3
    SI_MASK_BRANCH %bb.2, implicit $exec
    S_BRANCH %bb.1

  bb.1.if:
    liveins: $sgpr0_sgpr1

    $sgpr7 = S_MOV_B32 61440
    $sgpr6 = S_MOV_B32 -1
    $vgpr0 = BUFFER_LOAD_DWORD_OFFSET $sgpr4_sgpr5_sgpr6_sgpr7, 0, 0, 0, 0, 0, 0, 0, 0, implicit $exec

  bb.2.end:
    liveins: $vgpr0, $sgpr0_sgpr1

    $exec = S_OR_B64 $exec, killed $sgpr0_sgpr1, implicit-def $scc
    $sgpr3 = S_MOV_B32 61440
    $sgpr2 = S_MOV_B32 -1
    BUFFER_STORE_DWORD_OFFSET killed $vgpr0, $sgpr0_sgpr1_sgpr2_sgpr3, 0, 0, 0, 0, 0, 0, 0, 0, implicit $exec
    S_ENDPGM 0

...
---
# A read from exec copy subreg prevents optimization
# CHECK-LABEL: name: if_and_xor_read_exec_copy_subreg{{$}}
# CHECK: $sgpr0_sgpr1 = COPY $exec
# CHECK-NEXT: $sgpr4 = S_MOV_B32 $sgpr1
name:            if_and_xor_read_exec_copy_subreg
liveins:
  - { reg: '$vgpr0' }
body:             |
  bb.0.main_body:
    liveins: $vgpr0

    $sgpr0_sgpr1 = COPY $exec
    $sgpr4 = S_MOV_B32 $sgpr1
    $vcc = V_CMP_EQ_I32_e64 0, killed $vgpr0, implicit $exec
    $vgpr0 = V_MOV_B32_e32 4, implicit $exec
    $sgpr2_sgpr3 = S_AND_B64 $sgpr0_sgpr1, killed $vcc, implicit-def $scc
    $sgpr0_sgpr1 = S_XOR_B64 $sgpr2_sgpr3, killed $sgpr0_sgpr1, implicit-def $scc
    $exec = S_MOV_B64_term killed $sgpr2_sgpr3
    SI_MASK_BRANCH %bb.2, implicit $exec
    S_BRANCH %bb.1

  bb.1.if:
    liveins: $sgpr0_sgpr1

    $sgpr7 = S_MOV_B32 61440
    $sgpr6 = S_MOV_B32 -1
    $vgpr0 = BUFFER_LOAD_DWORD_OFFSET $sgpr4_sgpr5_sgpr6_sgpr7, 0, 0, 0, 0, 0, 0, 0, 0, implicit $exec

  bb.2.end:
    liveins: $vgpr0, $sgpr0_sgpr1

    $exec = S_OR_B64 $exec, killed $sgpr0_sgpr1, implicit-def $scc
    $sgpr3 = S_MOV_B32 61440
    $sgpr2 = S_MOV_B32 -1
    BUFFER_STORE_DWORD_OFFSET killed $vgpr0, $sgpr0_sgpr1_sgpr2_sgpr3, 0, 0, 0, 0, 0, 0, 0, 0, implicit $exec
    S_ENDPGM 0
...