# RUN: not --crash llc -mtriple=amdgcn-amd-amdhsa -mcpu=gfx906 -verify-machineinstrs  -run-pass=machine-scheduler -verify-misched -o /dev/null %s  2>&1  | FileCheck %s

# CHECK: *** Bad machine code: No live subrange at use ***
# CHECK-NEXT: - function:    at_least_one_value_should_be_defined_by_this_mask
# CHECK-NEXT: - basic block: %bb.0
# CHECK-NEXT: - instruction: 48B	dead undef %2.sub0:vreg_128 = COPY %0.sub0:vreg_128
# CHECK-NEXT: - operand 1:   %0.sub0:vreg_128
# CHECK-NEXT: - interval:    %0 [16r,48r:0)  0@16r L000000000000000C [16r,32r:0)  0@16r weight:0.000000e+00

# This used to assert with: !SR.empty() && "At least one value should be defined by this mask"

# This MIR is invalid and should be caught by the verifier. %0.sub0 is
# used, but not defined. There are also lanes in %0 that are not used
# or defined anywhere. Previously there was an assertion in the
# LiveInterval computation, which was more confusing. The invalid
# LiveRange should be produced and the verifier will catch it.

---
name: at_least_one_value_should_be_defined_by_this_mask
tracksRegLiveness: true
body:             |
  bb.0:

    undef %0.sub1:vreg_128 = V_MOV_B32_e32 0, implicit $exec
    %1:vreg_128 = COPY %0
    undef %2.sub0:vreg_128 = COPY %0.sub0

...