# RUN: not llc -march=x86-64 -run-pass none -o /dev/null %s 2>&1 | FileCheck %s
# This test ensures that an error is reported when an unknown subregister index
# is encountered.

--- |

  define zeroext i1 @t(i1 %c) {
  entry:
    ret i1 %c
  }

...
---
name:            t
tracksRegLiveness: true
registers:
  - { id: 0, class: gr32 }
  - { id: 1, class: gr8 }
  - { id: 2, class: gr8 }
body: |
  bb.0.entry:
    %0 = COPY $edi
    ; CHECK: [[@LINE+1]]:18: use of unknown subregister index 'bit8'
    %1 = COPY %0.bit8
    %2 = AND8ri %1, 1, implicit-def $eflags
    $al = COPY %2
    RETQ $al
...