# 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 register is
# encountered.

--- |

  define i32 @foo() {
  entry:
    ret i32 0
  }

...
---
name:            foo
body: |
  bb.0.entry:
    ; CHECK: [[@LINE+1]]:5: unknown register name 'xax'
    $xax = MOV32r0
    RETQ $xax
...