src/llvm-project/llvm/test/CodeGen/AMDGPU/spill-empty-live-interval.mir

# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py
# RUN: llc -mtriple=amdgcn-amd-amdhsa -verify-machineinstrs -amdgpu-dce-in-ra=0 -stress-regalloc=1 -start-before=register-coalescer -stop-after=greedy,1 -o - %s | FileCheck %s
# https://bugs.llvm.org/show_bug.cgi?id=33620

---
# This would assert due to the empty live interval created for %9
# on the last S_NOP with an undef subreg use.




name: expecting_non_empty_interval
tracksRegLiveness: true
machineFunctionInfo:
  scratchRSrcReg: $sgpr0_sgpr1_sgpr2_sgpr3
  stackPtrOffsetReg: $sgpr32
body:             |
  ; CHECK-LABEL: name: expecting_non_empty_interval
  ; CHECK: bb.0:
  ; CHECK-NEXT:   successors: %bb.1(0x80000000)
  ; CHECK-NEXT: {{  $}}
  ; CHECK-NEXT:   undef %5.sub1:vreg_64 = V_MOV_B32_e32 1786773504, implicit $exec
  ; CHECK-NEXT:   dead [[V_MUL_F32_e32_:%[0-9]+]]:vgpr_32 = V_MUL_F32_e32 0, %5.sub1, implicit $mode, implicit $exec
  ; CHECK-NEXT:   undef %7.sub1:vreg_64 = V_MAC_F32_e32 0, undef %1:vgpr_32, undef %7.sub1, implicit $mode, implicit $exec
  ; CHECK-NEXT:   SI_SPILL_V64_SAVE %7, %stack.0, $sgpr32, 0, implicit $exec :: (store (s64) into %stack.0, align 4, addrspace 5)
  ; CHECK-NEXT: {{  $}}
  ; CHECK-NEXT: bb.1:
  ; CHECK-NEXT:   undef %6.sub1:vreg_64 = V_MOV_B32_e32 1786773504, implicit $exec
  ; CHECK-NEXT:   S_NOP 0, implicit %6.sub1
  ; CHECK-NEXT:   [[SI_SPILL_V64_RESTORE:%[0-9]+]]:vreg_64 = SI_SPILL_V64_RESTORE %stack.0, $sgpr32, 0, implicit $exec :: (load (s64) from %stack.0, align 4, addrspace 5)
  ; CHECK-NEXT:   S_NOP 0, implicit [[SI_SPILL_V64_RESTORE]].sub1
  ; CHECK-NEXT:   S_NOP 0, implicit undef %9.sub0:vreg_64
  bb.0:
    successors: %bb.1

    undef %0.sub1:vreg_64 = V_MAC_F32_e32 0, undef %1:vgpr_32, undef %0.sub1, implicit $mode, implicit $exec
    undef %2.sub1:vreg_64 = V_MOV_B32_e32 1786773504, implicit $exec
    dead %3:vgpr_32 = V_MUL_F32_e32 0, %2.sub1, implicit $mode, implicit $exec

  bb.1:
    S_NOP 0, implicit %2.sub1
    S_NOP 0, implicit %0.sub1
    S_NOP 0, implicit undef %0.sub0

...

# Similar assert which happens when trying to rematerialize.
# https://bugs.llvm.org/show_bug.cgi?id=33884
---


name: rematerialize_empty_interval_has_reference
tracksRegLiveness: true
machineFunctionInfo:
  scratchRSrcReg: $sgpr0_sgpr1_sgpr2_sgpr3
  stackPtrOffsetReg: $sgpr32
body:             |
  ; CHECK-LABEL: name: rematerialize_empty_interval_has_reference
  ; CHECK: bb.0:
  ; CHECK-NEXT:   successors: %bb.1(0x80000000)
  ; CHECK-NEXT: {{  $}}
  ; CHECK-NEXT:   undef %1.sub2:vreg_128 = V_MOV_B32_e32 1786773504, implicit $exec
  ; CHECK-NEXT: {{  $}}
  ; CHECK-NEXT: bb.1:
  ; CHECK-NEXT:   S_NOP 0, implicit %1.sub2
  ; CHECK-NEXT:   undef %2.sub2:vreg_128 = V_MOV_B32_e32 0, implicit $exec
  ; CHECK-NEXT:   S_NOP 0, implicit %2.sub2
  ; CHECK-NEXT:   S_NOP 0, implicit undef %4.sub0:vreg_128
  bb.0:
    successors: %bb.1

    undef %0.sub2:vreg_128 = V_MOV_B32_e32 0, implicit $exec
    undef %1.sub2:vreg_128 = V_MOV_B32_e32 1786773504, implicit $exec

  bb.1:
    S_NOP 0, implicit %1.sub2
    S_NOP 0, implicit undef %0.sub0
    S_NOP 0, implicit %0.sub2

...