# RUN: llc < %s -x=mir -mtriple=x86_64-- -run-pass=simple-register-coalescing | FileCheck %s --- name: f body: | bb.0: JB_1 %bb.2, undef implicit killed $eflags JMP_1 %bb.1 bb.1: %0 : gr64 = IMPLICIT_DEF NOOP implicit-def undef %1.sub_32bit : gr64 NOOP implicit-def %1.sub_16bit : gr64 JMP_1 %bb.3 bb.2: NOOP implicit-def %0 %1 = COPY %0 bb.3: NOOP implicit killed %0 NOOP implicit killed %1 ... # We should have a setting of both sub_32bit and sub_16bit. The first one # should be undef and not dead, and the second should not be undef. # CHECK-NOT: dead # CHECK: NOOP implicit-def undef %1.sub_32bit # CHECK-NOT: undef # CHECK-NEXT: NOOP implicit-def %1.sub_16bit