llvm/llvm/test/CodeGen/SystemZ/machinesink-dead-cc.mir

# RUN: llc -mtriple=s390x-linux-gnu -mcpu=z15 -O3 -run-pass=machine-sink %s -o - \
# RUN:   -verify-machineinstrs | FileCheck %s
#
# Test that the AGHIK can be sunk into %bb.4. It has a def of CC, but it is dead.

--- |
  define void @fun() {  ret void  }
...

# CHECK-LABEL: bb.4:
# CHECK:         %1:gr64bit = nsw AGHIK %0, -4, implicit-def dead $cc
# CHECK-NEXT:    CGHI %1, 0, implicit-def $cc
# CHECK-NEXT:    BRC 14, 6, %bb.1, implicit $cc
# CHECK-NEXT:    J %bb.5


---
name:            fun
alignment:       16
tracksRegLiveness: true
registers:
  - { id: 0, class: gr64bit }
  - { id: 1, class: gr64bit }
  - { id: 2, class: grx32bit }
  - { id: 3, class: gr64bit }
frameInfo:
  maxAlignment:    1
machineFunctionInfo: {}
body:             |
  bb.0:

    %2:grx32bit = LHIMux 0
    %3:gr64bit = IMPLICIT_DEF

  bb.1:

    %0:gr64bit = PHI %3, %bb.0, %1, %bb.4
  
  bb.2:
  
    %1:gr64bit = nsw AGHIK %0, -4, implicit-def dead $cc
    CHIMux %2, 0, implicit-def $cc
    BRC 14, 6, %bb.4, implicit $cc
    J %bb.3
  
  bb.3:
  
  bb.4:
  
    CGHI %1, 0, implicit-def $cc
    BRC 14, 6, %bb.1, implicit $cc
    J %bb.5
  
  bb.5:
    Return

...