test/CodeGen/MIR/X86/unknown-register.mir

# RUN: not llc -march=x86-64 -start-after branch-folder -stop-after branch-folder -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:
 - id:           0
   name:         entry
   instructions:
     # CHECK: [[@LINE+1]]:9: unknown register name 'xax'
     - '%xax = MOV32r0'
     - 'RETQ %xax'
...