test/CodeGen/X86/implicit-use-spill.mir

# RUN: llc -run-pass=greedy -mtriple=x86_64-apple-macosx -o - %s | FileCheck %s

# Make sure we don't assert when we try to reload a value that is just implicitly used.
---
# CHECK: name: foo
# This test forces a spill of %0.
name: foo
registers:
  - { id: 0, class: gr64 }
body: |
  bb.0:
  ; CHECK: NOOP implicit-def [[VAL:%[0-9]+]]
  ; VAL should be spilled before csr_noregs, i.e., before we clobber all the registers
  ; CHECK-NEXT: MOV64mr [[SLOT:%stack.[0-9]+]], 1, _, 0, _, [[VAL]]
  ; CHECK-NEXT: NOOP csr_noregs
  ; We need to reload before the (implicit) use.
  ; CHECK-NEXT: [[RELOADED_VAL:%[0-9]+]] = MOV64rm [[SLOT]], 1, _, 0, _
  ; CHECK-NEXT: NOOP implicit [[RELOADED_VAL]]
  NOOP implicit-def %0
  NOOP csr_noregs
  NOOP implicit %0
...