llvm/llvm/test/CodeGen/AArch64/fast-regalloc-empty-bb-with-liveins.mir

# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py
# RUN: llc -mtriple aarch64-apple-ios -run-pass regallocfast -o - %s | FileCheck %s
# RUN: llc -mtriple aarch64-apple-ios -passes=regallocfast -o - %s | FileCheck %s
# This test used to crash the fast register alloc.
# Basically, when a basic block has liveins, the fast regalloc
# was deferencing the begin iterator of this block. However,
# when this block is empty and it will just crashed!
---
name:            crashing
tracksRegLiveness: true
body:             |
  ; CHECK-LABEL: name: crashing
  ; CHECK: bb.0:
  ; CHECK:   successors: %bb.1(0x80000000)
  ; CHECK:   liveins: $x0, $x1
  ; CHECK: bb.1:
  ; CHECK:   renamable $w0 = MOVi32imm -1
  ; CHECK:   RET_ReallyLR implicit killed $w0
  bb.1:
    liveins: $x0, $x1

  bb.2:
    %0:gpr32 = MOVi32imm -1
    $w0 = COPY %0
    RET_ReallyLR implicit $w0

...