llvm-project/llvm/test/CodeGen/Hexagon/livephysregs-lane-masks.mir

# RUN: llc -march=hexagon -run-pass if-converter -verify-machineinstrs -o - %s | FileCheck %s

# CHECK-LABEL: name: foo
# CHECK: %p0 = C2_cmpeqi %r16, 0
# Make sure there is no implicit use of r1.
# CHECK: %r1 = L2_ploadruhf_io %p0, %r29, 6

--- |
  define void @foo() {
    ret void
  }
...


---
name: foo
tracksRegLiveness: true

body: |
  bb.0:
    liveins: %r16
    successors: %bb.1, %bb.2
        %p0 = C2_cmpeqi %r16, 0
        J2_jumpt %p0, %bb.2, implicit-def %pc

  bb.1:
    ; The lane mask %d0:0002 is equivalent to %r0. LivePhysRegs would ignore
    ; it and treat it as the whole %d0, which is a pair %r1, %r0. The extra
    ; %r1 would cause an (undefined) implicit use to be added during
    ; if-conversion.
    liveins: %d0:0x00000002, %d15:0x00000001, %r16
    successors: %bb.2
        %r1 = L2_loadruh_io %r29, 6
        S2_storeri_io killed %r16, 0, %r1

  bb.2:
    liveins: %r0
        %d8 = L2_loadrd_io %r29, 8
        %d15 = L4_return %r29, implicit-def %r29, implicit-def %pc, implicit %r30, implicit %framekey