Compiler projects using llvm
# RUN: llc -mtriple=x86_64-- -run-pass=regallocfast -o - %s | FileCheck %s

# If the tied use is undef value, fastregalloc should free the def register.
# There is no reload needed for the undef value.
...
---
name:            foo
alignment:       16
tracksRegLiveness: true
registers:
  - { id: 0, class: vr128 }
frameInfo:
  maxAlignment:    16
stack:
  - { id: 0, size: 64, alignment: 16 }
  - { id: 1, size: 16, alignment: 16 }
machineFunctionInfo: {}
body:             |
  bb.0.entry:
    ; CHECK-LABEL: bb.0.entry
    ; CHECK-NEXT: renamable $xmm0 = PXORrr undef renamable $xmm0, undef renamable $xmm0
    ; CHECK-NEXT: MOVAPSmr %stack.1, 1, $noreg, 0, $noreg, renamable $xmm0
    ; CHECK-NEXT: MOVAPSmr %stack.0, 1, $noreg, 0, $noreg, renamable $xmm0
    ; CHECK-NEXT: MOVAPSmr %stack.0, 1, $noreg, 16, $noreg, renamable $xmm0
    ; CHECK-NEXT: MOVAPSmr %stack.0, 1, $noreg, 32, $noreg, renamable $xmm0
    ; CHECK-NEXT: MOVAPSmr %stack.0, 1, $noreg, 48, $noreg, killed renamable $xmm0

    %0:vr128 = PXORrr undef %0, undef %0
    MOVAPSmr %stack.1, 1, $noreg, 0, $noreg, %0
    MOVAPSmr %stack.0, 1, $noreg, 0, $noreg, %0
    MOVAPSmr %stack.0, 1, $noreg, 16, $noreg, %0
    MOVAPSmr %stack.0, 1, $noreg, 32, $noreg, %0
    MOVAPSmr %stack.0, 1, $noreg, 48, $noreg, killed %0
    RET 0

...