llvm/test/CodeGen/AMDGPU/twoaddr-insert-subreg-undef.mir

# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py UTC_ARGS: --version 6
# RUN: llc -mtriple=amdgpu9.42 -run-pass=liveintervals,two-address-instruction -o - %s | FileCheck %s

# An undef super-register source leaves the lanes outside
# sub0_sub1_sub2_sub3 undefined, but they are still read. They need an
# IMPLICIT_DEF.

---
name:            insert_subreg_undef_lanes_read
tracksRegLiveness: true
body: |
  bb.0:
    liveins: $vgpr8_vgpr9_vgpr10_vgpr11

    ; CHECK-LABEL: name: insert_subreg_undef_lanes_read
    ; CHECK: liveins: $vgpr8_vgpr9_vgpr10_vgpr11
    ; CHECK-NEXT: {{  $}}
    ; CHECK-NEXT: dead [[DEF:%[0-9]+]]:vreg_256 = IMPLICIT_DEF
    ; CHECK-NEXT: [[COPY:%[0-9]+]]:vreg_128 = COPY $vgpr8_vgpr9_vgpr10_vgpr11
    ; CHECK-NEXT: [[DEF1:%[0-9]+]]:vreg_256 = IMPLICIT_DEF
    ; CHECK-NEXT: [[DEF1:%[0-9]+]].sub0_sub1_sub2_sub3:vreg_256 = COPY [[COPY]]
    ; CHECK-NEXT: $vgpr12_vgpr13_vgpr14_vgpr15 = COPY [[DEF1]].sub4_sub5_sub6_sub7
    ; CHECK-NEXT: $vgpr8_vgpr9_vgpr10_vgpr11 = COPY [[DEF1]].sub0_sub1_sub2_sub3
    ; CHECK-NEXT: SI_RETURN implicit $vgpr8_vgpr9_vgpr10_vgpr11, implicit $vgpr12_vgpr13_vgpr14_vgpr15
    %0:vreg_256 = IMPLICIT_DEF
    %1:vreg_128 = COPY $vgpr8_vgpr9_vgpr10_vgpr11
    %2:vreg_256 = INSERT_SUBREG undef %0, %1, %subreg.sub0_sub1_sub2_sub3
    $vgpr12_vgpr13_vgpr14_vgpr15 = COPY %2.sub4_sub5_sub6_sub7
    $vgpr8_vgpr9_vgpr10_vgpr11 = COPY %2.sub0_sub1_sub2_sub3
    SI_RETURN implicit $vgpr8_vgpr9_vgpr10_vgpr11, implicit $vgpr12_vgpr13_vgpr14_vgpr15
...

# Nothing reads the undefined lanes, so no IMPLICIT_DEF is needed.

---
name:            insert_subreg_undef_lanes_unused
tracksRegLiveness: true
body: |
  bb.0:
    liveins: $vgpr8_vgpr9_vgpr10_vgpr11

    ; CHECK-LABEL: name: insert_subreg_undef_lanes_unused
    ; CHECK: liveins: $vgpr8_vgpr9_vgpr10_vgpr11
    ; CHECK-NEXT: {{  $}}
    ; CHECK-NEXT: dead [[DEF:%[0-9]+]]:vreg_256 = IMPLICIT_DEF
    ; CHECK-NEXT: [[COPY:%[0-9]+]]:vreg_128 = COPY $vgpr8_vgpr9_vgpr10_vgpr11
    ; CHECK-NEXT: undef [[COPY1:%[0-9]+]].sub0_sub1_sub2_sub3:vreg_256 = COPY [[COPY]]
    ; CHECK-NEXT: $vgpr8_vgpr9_vgpr10_vgpr11 = COPY [[COPY1]].sub0_sub1_sub2_sub3
    ; CHECK-NEXT: SI_RETURN implicit $vgpr8_vgpr9_vgpr10_vgpr11
    %0:vreg_256 = IMPLICIT_DEF
    %1:vreg_128 = COPY $vgpr8_vgpr9_vgpr10_vgpr11
    %2:vreg_256 = INSERT_SUBREG undef %0, %1, %subreg.sub0_sub1_sub2_sub3
    $vgpr8_vgpr9_vgpr10_vgpr11 = COPY %2.sub0_sub1_sub2_sub3
    SI_RETURN implicit $vgpr8_vgpr9_vgpr10_vgpr11
...