llvm-project/llvm/test/CodeGen/AMDGPU/regcoal-subrange-join.mir

# RUN: llc -march=amdgcn -run-pass simple-register-coalescing -o - %s | FileCheck --check-prefix=GCN %s
#
# See bug http://llvm.org/PR33524 for details of the problem being checked here
# This test will provoke a subrange join (see annotations below) during simple register coalescing
# Without a fix for PR33524 this causes an unreachable in SubRange Join
#
# GCN-DAG: undef %[[REG0:[0-9]+]].sub0:sgpr_64 = COPY $sgpr5
# GCN-DAG: undef %[[REG1:[0-9]+]].sub0:sgpr_64 = COPY $sgpr2
# GCN-DAG: %[[REG0]].sub1:sgpr_64 = S_MOV_B32 1
# GCN-DAG: %[[REG1]].sub1:sgpr_64 = S_MOV_B32 1

--- |
  define amdgpu_vs void @regcoal-subrange-join(i32 inreg %arg, i32 inreg %arg1, i32 inreg %arg2, i32 inreg %arg3, i32 inreg %arg4, i32 inreg %arg5, i32 %arg6) local_unnamed_addr #0 {
    ret void
  }

...
---
name:            regcoal-subrange-join
tracksRegLiveness: true
registers:
  - { id: 0, class: sreg_64 }
  - { id: 1, class: vreg_128 }
  - { id: 2, class: vreg_128 }
  - { id: 3, class: vreg_128 }
  - { id: 4, class: sreg_32_xm0 }
  - { id: 5, class: sreg_32_xm0 }
  - { id: 6, class: sreg_32_xm0, preferred-register: '%8' }
  - { id: 7, class: vreg_128 }
  - { id: 8, class: sreg_32_xm0, preferred-register: '%6' }
  - { id: 9, class: vreg_128 }
  - { id: 10, class: sgpr_32 }
  - { id: 11, class: sgpr_32 }
  - { id: 12, class: sgpr_32 }
  - { id: 13, class: sgpr_32 }
  - { id: 14, class: sgpr_32 }
  - { id: 15, class: sgpr_32 }
  - { id: 16, class: vgpr_32 }
  - { id: 17, class: sreg_32_xm0 }
  - { id: 18, class: sreg_64 }
  - { id: 19, class: sreg_32_xm0 }
  - { id: 20, class: sreg_32_xm0 }
  - { id: 21, class: sreg_64 }
  - { id: 22, class: sreg_32_xm0_xexec }
  - { id: 23, class: sreg_32_xm0 }
  - { id: 24, class: sreg_64_xexec }
  - { id: 25, class: sreg_128 }
  - { id: 26, class: sreg_64_xexec }
  - { id: 27, class: sreg_32_xm0_xexec }
  - { id: 28, class: sreg_32_xm0 }
  - { id: 29, class: vgpr_32 }
  - { id: 30, class: vgpr_32 }
  - { id: 31, class: vgpr_32 }
  - { id: 32, class: vgpr_32 }
  - { id: 33, class: vgpr_32 }
  - { id: 34, class: vgpr_32 }
  - { id: 35, class: vgpr_32 }
  - { id: 36, class: vgpr_32 }
  - { id: 37, class: vgpr_32 }
  - { id: 38, class: sreg_128 }
  - { id: 39, class: sreg_64_xexec }
  - { id: 40, class: sreg_32_xm0_xexec }
  - { id: 41, class: sreg_32_xm0 }
  - { id: 42, class: vgpr_32 }
  - { id: 43, class: vgpr_32 }
  - { id: 44, class: vgpr_32 }
  - { id: 45, class: vgpr_32 }
  - { id: 46, class: vgpr_32 }
  - { id: 47, class: vgpr_32 }
  - { id: 48, class: vgpr_32 }
  - { id: 49, class: vgpr_32 }
  - { id: 50, class: vgpr_32 }
  - { id: 51, class: sreg_128 }
  - { id: 52, class: vgpr_32 }
  - { id: 53, class: vgpr_32 }
  - { id: 54, class: vgpr_32 }
  - { id: 55, class: vgpr_32 }
  - { id: 56, class: vreg_128 }
  - { id: 57, class: vreg_128 }
  - { id: 58, class: vreg_128 }
  - { id: 59, class: sreg_32_xm0 }
  - { id: 60, class: sreg_32_xm0 }
  - { id: 61, class: vreg_128 }
liveins:
  - { reg: '$sgpr2', virtual-reg: '%12' }
  - { reg: '$sgpr5', virtual-reg: '%15' }
body:             |
  bb.0:
    liveins: $sgpr2, $sgpr5

    %15 = COPY killed $sgpr5
    %12 = COPY killed $sgpr2
    %17 = S_MOV_B32 1
    undef %18.sub1 = COPY %17
    %0 = COPY %18
    %0.sub0 = COPY killed %12
    %21 = COPY killed %18
    %21.sub0 = COPY killed %15
    %22 = S_LOAD_DWORD_IMM killed %21, 2, 0
    %23 = S_MOV_B32 491436
    undef %24.sub0 = COPY killed %22
    %24.sub1 = COPY killed %23
    %25 = S_LOAD_DWORDX4_IMM killed %24, 0, 0
    %1 = COPY killed %25
    %26 = S_LOAD_DWORDX2_IMM %0, 2, 0
    dead %27 = S_LOAD_DWORD_IMM killed %26, 0, 0
    S_CBRANCH_SCC0 %bb.1, implicit undef $scc

  bb.5:
    %58 = COPY killed %1
    %59 = COPY killed %17
    S_BRANCH %bb.2

  bb.1:
    %30 = V_MOV_B32_e32 1036831949, implicit $exec
    %31 = V_ADD_F32_e32 %30, %1.sub3, implicit $exec
    %33 = V_ADD_F32_e32 %30, %1.sub2, implicit $exec
    %35 = V_ADD_F32_e32 %30, %1.sub1, implicit $exec
    %37 = V_ADD_F32_e32 killed %30, killed %1.sub0, implicit $exec
    undef %56.sub0 = COPY killed %37
    %56.sub1 = COPY killed %35
    %56.sub2 = COPY killed %33
    %56.sub3 = COPY killed %31
    %28 = S_MOV_B32 0
    %2 = COPY killed %56
    %58 = COPY killed %2
    %59 = COPY killed %28

  bb.2:
    %4 = COPY killed %59
    %3 = COPY killed %58
    %39 = S_LOAD_DWORDX2_IMM killed %0, 6, 0
    %40 = S_LOAD_DWORD_IMM killed %39, 0, 0
    %43 = V_MOV_B32_e32 -1102263091, implicit $exec
    %60 = COPY killed %4
    %61 = COPY killed %3

  bb.3:
    successors: %bb.3, %bb.4

    %7 = COPY killed %61
    %6 = COPY killed %60
    %8 = S_ADD_I32 killed %6, 1, implicit-def dead $scc
    %44 = V_ADD_F32_e32 %43, %7.sub3, implicit $exec
    %46 = V_ADD_F32_e32 %43, %7.sub2, implicit $exec
    %48 = V_ADD_F32_e32 %43, %7.sub1, implicit $exec
    %50 = V_ADD_F32_e32 %43, killed %7.sub0, implicit $exec
    undef %57.sub0 = COPY killed %50
    %57.sub1 = COPY killed %48
    %57.sub2 = COPY %46
    %57.sub3 = COPY killed %44
    S_CMP_LT_I32 %8, %40, implicit-def $scc
    %60 = COPY killed %8
    %61 = COPY killed %57
    S_CBRANCH_SCC1 %bb.3, implicit killed $scc
    S_BRANCH %bb.4

  bb.4:
    EXP 32, undef %53, undef %54, killed %46, undef %55, 0, 0, 15, implicit $exec
    S_ENDPGM

...