regcoal-undef-lane-4-rm-cp-commuting-def.mir 4.8 KB
# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py
# RUN: llc -run-pass simple-register-coalescing %s -systemz-subreg-liveness -O3 -mtriple s390x-ibm-linux -mcpu z13 -o - | FileCheck %s
#
# When the coalescing tries to coalesce `%20 = COPY %18`,
# %18 has been coalesced all the way up to %15 = ROSBG.
# ROSBG has tied operands and can be commuted, thus it
# maybe possible to swap the arguments of ROSBG to coalesce
# this copy. That's what the coalescer attempts.
#
# This used to produce an assertion failure in the coalescer,
# because this particular coalescing trick is used only on
# full copy. Therefore we were asserting that all the subranges
# at the point of the copy had a value number.
# This is actually not true in that example, because %18 is
# only partial defined before being fully copied.
#
# PR40215.
---
name:            main
alignment:       16
tracksRegLiveness: true
machineFunctionInfo: {}
body:             |
  ; CHECK-LABEL: name: main
  ; CHECK: bb.0:
  ; CHECK:   successors: %bb.1(0x80000000)
  ; CHECK:   [[LGHI:%[0-9]+]]:addr64bit = LGHI -30
  ; CHECK:   [[LHIMux:%[0-9]+]]:grx32bit = LHIMux 1
  ; CHECK:   [[LHIMux1:%[0-9]+]]:grx32bit = LHIMux 0
  ; CHECK:   undef %20.subreg_l32:gr64bit = IMPLICIT_DEF
  ; CHECK: bb.1:
  ; CHECK:   successors: %bb.3(0x00000001), %bb.4(0x7fffffff)
  ; CHECK:   CHIMux [[LHIMux]], 0, implicit-def $cc
  ; CHECK:   BRC 14, 6, %bb.3, implicit killed $cc
  ; CHECK:   J %bb.4
  ; CHECK: bb.2:
  ; CHECK:   successors:
  ; CHECK:   STMux %20.subreg_l32, undef %8:addr64bit, 0, $noreg :: (store 4 into `i32* undef`)
  ; CHECK: bb.3:
  ; CHECK:   successors:
  ; CHECK: bb.4:
  ; CHECK:   successors: %bb.5(0x30000000), %bb.6(0x50000000)
  ; CHECK:   [[LAY:%[0-9]+]]:gr64bit = LAY [[LGHI]], 19838, $noreg
  ; CHECK:   [[LAY1:%[0-9]+]]:gr64bit = LAY [[LGHI]], 19840, $noreg
  ; CHECK:   [[LAY2:%[0-9]+]]:gr64bit = LAY [[LGHI]], 19844, $noreg
  ; CHECK:   [[OGR:%[0-9]+]]:gr64bit = OGR [[OGR]], [[LAY]], implicit-def dead $cc
  ; CHECK:   undef %19.subreg_l32:gr64bit = AHIMuxK [[LGHI]].subreg_l32, 19843, implicit-def dead $cc
  ; CHECK:   [[ROSBG:%[0-9]+]]:gr64bit = ROSBG [[ROSBG]], [[OGR]], 32, 63, 0, implicit-def dead $cc
  ; The coalescer should have been able to swap the operands of
  ; the OR, hence eliminating the copy of %20 and %18.
  ; This is also visible here because the ROSBG operand was LHS
  ; before the coalescer, now it is RHS.
  ; CHECK:   %20.subreg_l32:gr64bit = OR %20.subreg_l32, [[ROSBG]].subreg_l32, implicit-def dead $cc
  ; CHECK:   [[ROSBG1:%[0-9]+]]:gr64bit = ROSBG [[ROSBG1]], [[LAY1]], 32, 63, 0, implicit-def dead $cc
  ; CHECK:   CHIMux [[LHIMux1]], 0, implicit-def $cc
  ; CHECK:   BRC 14, 6, %bb.6, implicit killed $cc
  ; CHECK:   J %bb.5
  ; CHECK: bb.5:
  ; CHECK:   successors: %bb.6(0x80000000)
  ; CHECK: bb.6:
  ; CHECK:   successors: %bb.2(0x00000001), %bb.7(0x7fffffff)
  ; CHECK:   [[LGHI]]:addr64bit = nuw nsw LA [[LGHI]], 6, $noreg
  ; CHECK:   CGHI [[LGHI]], 0, implicit-def $cc
  ; CHECK:   BRC 14, 8, %bb.2, implicit killed $cc
  ; CHECK: bb.7:
  ; CHECK:   successors: %bb.1(0x80000000)
  ; CHECK:   J %bb.1
  bb.0:
    %6:gr64bit = LGHI -30
    %8:grx32bit = LHIMux 1
    %21:grx32bit = LHIMux 0
    %23:addr64bit = COPY killed %6
    %24:gr32bit = IMPLICIT_DEF

  bb.1:
    successors: %bb.3(0x00000001), %bb.4(0x7fffffff)

    %1:gr32bit = COPY killed %24
    %0:addr64bit = COPY killed %23
    CHIMux %8, 0, implicit-def $cc
    BRC 14, 6, %bb.3, implicit killed $cc
    J %bb.4

  bb.2:
    successors:

    STMux killed %4, undef %22:addr64bit, 0, $noreg :: (store 4 into `i32* undef`)

  bb.3:
    successors:


  bb.4:
    successors: %bb.5(0x30000000), %bb.6(0x50000000)

    %2:gr64bit = LAY %0, 19838, $noreg
    %3:gr64bit = LAY %0, 19840, $noreg
    %9:gr64bit = LAY %0, 19844, $noreg
    %10:gr64bit = COPY killed %9
    %10:gr64bit = OGR %10, killed %2, implicit-def dead $cc
    %11:gr32bit = COPY %0.subreg_l32
    %12:gr32bit = AHIMuxK killed %11, 19843, implicit-def dead $cc
    undef %13.subreg_l32:gr64bit = COPY killed %12
    %15:gr64bit = COPY killed %13
    %15:gr64bit = ROSBG %15, killed %10, 32, 63, 0, implicit-def dead $cc
    %16:gr32bit = COPY killed %15.subreg_l32
    %17:gr32bit = COPY killed %16
    %17:gr32bit = OR %17, killed %1, implicit-def dead $cc
    undef %18.subreg_l32:gr64bit = COPY killed %17
    %20:gr64bit = COPY killed %18
    %20:gr64bit = ROSBG %20, killed %3, 32, 63, 0, implicit-def dead $cc
    CHIMux %21, 0, implicit-def $cc
    BRC 14, 6, %bb.6, implicit killed $cc
    J %bb.5

  bb.5:

  bb.6:
    successors: %bb.2(0x00000001), %bb.7(0x7fffffff)

    %4:grx32bit = COPY killed %20.subreg_l32
    %5:gr64bit = nuw nsw LA killed %0, 6, $noreg
    CGHI %5, 0, implicit-def $cc
    BRC 14, 8, %bb.2, implicit killed $cc

  bb.7:
    %23:addr64bit = COPY killed %5
    %24:gr32bit = COPY killed %4
    J %bb.1

...