llvm/test/CodeGen/X86/llc-print-machineinstrs.mir

# Check that -print-machineinstrs doesn't assert when it's passed an unknown pass name.
# RUN: llc -mtriple=x86_64-- -start-before=greedy -print-machineinstrs=greedy %s -o /dev/null
# RUN: not --crash llc -mtriple=x86_64-- -start-before=greedy -print-machineinstrs=unknown %s -o /dev/null 2>&1 | FileCheck %s
# CHECK: LLVM ERROR: "unknown" pass is not registered.

...
---
name: fun
tracksRegLiveness: true
body: |
  bb.0:
    RET 0