llvm/llvm/test/CodeGen/AArch64/scheduledag-constreg.mir

# RUN: llc -o /dev/null %s -mtriple=aarch64-- -run-pass=machine-scheduler -enable-misched -debug-only=machine-scheduler 2>&1 | FileCheck %s
# REQUIRES: asserts
--- |
  define void @func() { ret void }
...
---
# Check that the instructions are not dependent on each other, even though
# they all read/write to the zero register.
# CHECK-LABEL: MI Scheduling
# CHECK: SU(0): dead $wzr = SUBSWri $w1, 0, 0, implicit-def dead $nzcv
# CHECK: # succs left : 0
# CHECK-NOT: Successors:
# CHECK: SU(1): $w2 = COPY $wzr
# CHECK: # succs left : 0
# CHECK-NOT: Successors:
# CHECK: SU(2): dead $wzr = SUBSWri $w3, 0, 0, implicit-def dead $nzcv
# CHECK: # succs left : 0
# CHECK-NOT: Successors:
# CHECK: SU(3): $w4 = COPY $wzr
# CHECK: # succs left : 0
# CHECK-NOT: Successors:
name: func
body: |
  bb.0:
    dead $wzr = SUBSWri $w1, 0, 0, implicit-def dead $nzcv
    $w2 = COPY $wzr
    dead $wzr = SUBSWri $w3, 0, 0, implicit-def dead $nzcv
    $w4 = COPY $wzr
...