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|
# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py UTC_ARGS: --version 5
# RUN: llc -verify-machineinstrs -mtriple aarch64-none-linux-gnu -run-pass early-tailduplication -o - %s | FileCheck %s
# These tests used to hit verification failure due to register class
# mismatches after tail dupilication (and the SSA form updates).
# In test1 we have a simple case when the COPY already is duplicated, but
# TailDuplication will try to eliminate the PHI in bb.2 by adding a new PHI in
# bb.4. The presence of a PHI node in bb.4, which happens to assign to a
# fpr32 register, was enough to mess up the result. The PHI node was reused
# and the use of %2 in the CBNZW was changed into using %3 instead. But the
# register class of %3 is not correct for CBNZW.
# The fix involves adding a COPY instruction that moves the value to
# a register of correct regclass.
---
name: test1
tracksRegLiveness: true
body: |
; CHECK-LABEL: name: test1
; CHECK: bb.0:
; CHECK-NEXT: successors: %bb.4(0x80000000)
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: $x0 = COPY undef $x0, implicit-def %0
; CHECK-NEXT: B %bb.4
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: bb.1:
; CHECK-NEXT: successors: %bb.4(0x80000000)
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: $x0 = COPY undef $x0, implicit-def %1
; CHECK-NEXT: B %bb.4
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: bb.3:
; CHECK-NEXT: successors: %bb.3(0x80000000)
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: B %bb.3
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: bb.4:
; CHECK-NEXT: successors: %bb.5(0x80000000)
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: [[PHI:%[0-9]+]]:fpr32 = PHI %0, %bb.0, %1, %bb.1
; CHECK-NEXT: [[COPY:%[0-9]+]]:gpr32 = COPY [[PHI]]
; CHECK-NEXT: $x0 = COPY undef $x0, implicit [[PHI]]
; CHECK-NEXT: CBNZW [[COPY]], %bb.5
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: bb.5:
bb.0:
$x0 = COPY undef $x0, implicit-def %0:gpr32
B %bb.2
bb.1:
$x0 = COPY undef $x0, implicit-def %1:gpr32
bb.2:
%2:gpr32 = PHI %1, %bb.1, %0, %bb.0
B %bb.4
bb.3:
B %bb.3
bb.4:
%3:fpr32 = PHI %2, %bb.2
$x0 = COPY undef $x0, implicit %3:fpr32
CBNZW %2, %bb.5
bb.5:
...
# In test2 there are two PHIs already present, one with the wanted register
# class. No idea if this is a common scenario in reality (hand written mir
# test case).
# FIXME: Can we pick the best PHI directly instead of getting a COPY from the
# one with wrong register class?
---
name: test2
tracksRegLiveness: true
body: |
; CHECK-LABEL: name: test2
; CHECK: bb.0:
; CHECK-NEXT: successors: %bb.4(0x80000000)
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: $x0 = COPY undef $x0, implicit-def %0
; CHECK-NEXT: B %bb.4
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: bb.1:
; CHECK-NEXT: successors: %bb.4(0x80000000)
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: $x0 = COPY undef $x0, implicit-def %1
; CHECK-NEXT: B %bb.4
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: bb.3:
; CHECK-NEXT: successors: %bb.3(0x80000000)
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: B %bb.3
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: bb.4:
; CHECK-NEXT: successors: %bb.5(0x80000000)
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: [[PHI:%[0-9]+]]:fpr32 = PHI %0, %bb.0, %1, %bb.1
; CHECK-NEXT: [[PHI1:%[0-9]+]]:gpr32 = PHI %0, %bb.0, %1, %bb.1
; CHECK-NEXT: [[COPY:%[0-9]+]]:gpr32 = COPY [[PHI]]
; CHECK-NEXT: CBNZW [[COPY]], %bb.5
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: bb.5:
; CHECK-NEXT: $x0 = COPY undef $x0, implicit [[PHI]]
bb.0:
$x0 = COPY undef $x0, implicit-def %0:gpr32
B %bb.2
bb.1:
$x0 = COPY undef $x0, implicit-def %1:gpr32
bb.2:
%2:gpr32 = PHI %1, %bb.1, %0, %bb.0
B %bb.4
bb.3:
B %bb.3
bb.4:
%3:fpr32 = PHI %2, %bb.2
%4:gpr32 = PHI %2, %bb.2
CBNZW %2, %bb.5
bb.5:
$x0 = COPY undef $x0, implicit %3:fpr32
...
# In test3 we have multiple uses, and in multiple BBs. This test is to show
# that we get one COPY instruction inserted for each BB where there is a use.
---
name: test3
tracksRegLiveness: true
body: |
; CHECK-LABEL: name: test3
; CHECK: bb.0:
; CHECK-NEXT: successors: %bb.4(0x80000000)
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: $x0 = COPY undef $x0, implicit-def %0
; CHECK-NEXT: B %bb.4
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: bb.1:
; CHECK-NEXT: successors: %bb.4(0x80000000)
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: $x0 = COPY undef $x0, implicit-def %1
; CHECK-NEXT: B %bb.4
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: bb.3:
; CHECK-NEXT: successors: %bb.3(0x80000000)
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: B %bb.3
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: bb.4:
; CHECK-NEXT: successors: %bb.5(0x80000000)
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: [[PHI:%[0-9]+]]:fpr32 = PHI %0, %bb.0, %1, %bb.1
; CHECK-NEXT: $x0 = COPY undef $x0, implicit [[PHI]]
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: bb.5:
; CHECK-NEXT: successors: %bb.6(0x80000000)
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: [[COPY:%[0-9]+]]:gpr32 = COPY [[PHI]]
; CHECK-NEXT: CBNZW [[COPY]], %bb.6
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: bb.6:
; CHECK-NEXT: successors: %bb.7(0x80000000)
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: [[COPY1:%[0-9]+]]:gpr32 = COPY [[PHI]]
; CHECK-NEXT: CBNZW [[COPY1]], %bb.7
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: bb.7:
bb.0:
$x0 = COPY undef $x0, implicit-def %0:gpr32
B %bb.2
bb.1:
$x0 = COPY undef $x0, implicit-def %1:gpr32
bb.2:
%2:gpr32 = PHI %1, %bb.1, %0, %bb.0
B %bb.4
bb.3:
B %bb.3
bb.4:
%3:fpr32 = PHI %2, %bb.2
$x0 = COPY undef $x0, implicit %3:fpr32
bb.5:
CBNZW %2, %bb.6
bb.6:
CBNZW %2, %bb.7
bb.7:
...
# In test4 we do not need to insert a COPY.
# The register class can be constrained instead.
---
name: test4
tracksRegLiveness: true
body: |
; CHECK-LABEL: name: test4
; CHECK: bb.0:
; CHECK-NEXT: successors: %bb.4(0x80000000)
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: $x0 = COPY undef $x0, implicit-def %0
; CHECK-NEXT: B %bb.4
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: bb.1:
; CHECK-NEXT: successors: %bb.4(0x80000000)
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: $x0 = COPY undef $x0, implicit-def %1
; CHECK-NEXT: B %bb.4
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: bb.3:
; CHECK-NEXT: successors: %bb.3(0x80000000)
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: B %bb.3
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: bb.4:
; CHECK-NEXT: successors: %bb.5(0x80000000)
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: [[PHI:%[0-9]+]]:gpr32common = PHI %0, %bb.0, %1, %bb.1
; CHECK-NEXT: CBNZW [[PHI]], %bb.5
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: bb.5:
bb.0:
$x0 = COPY undef $x0, implicit-def %0:gpr32
B %bb.2
bb.1:
$x0 = COPY undef $x0, implicit-def %1:gpr32
bb.2:
%2:gpr32 = PHI %1, %bb.1, %0, %bb.0
B %bb.4
bb.3:
B %bb.3
bb.4:
%3:gpr32sp = PHI %2, %bb.2
CBNZW %2, %bb.5
bb.5:
...
# In test5 we do not need to insert a COPY.
# The register class can be constrained instead.
---
name: test5
tracksRegLiveness: true
body: |
; CHECK-LABEL: name: test5
; CHECK: bb.0:
; CHECK-NEXT: successors: %bb.4(0x80000000)
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: $x0 = COPY undef $x0, implicit-def %0
; CHECK-NEXT: B %bb.4
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: bb.1:
; CHECK-NEXT: successors: %bb.4(0x80000000)
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: $x0 = COPY undef $x0, implicit-def %1
; CHECK-NEXT: B %bb.4
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: bb.3:
; CHECK-NEXT: successors: %bb.3(0x80000000)
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: B %bb.3
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: bb.4:
; CHECK-NEXT: successors: %bb.5(0x80000000)
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: [[PHI:%[0-9]+]]:gpr32common = PHI %0, %bb.0, %1, %bb.1
; CHECK-NEXT: CBNZW [[PHI]], %bb.5
; CHECK-NEXT: {{ $}}
; CHECK-NEXT: bb.5:
bb.0:
$x0 = COPY undef $x0, implicit-def %0:gpr32common
B %bb.2
bb.1:
$x0 = COPY undef $x0, implicit-def %1:gpr32common
bb.2:
%2:gpr32common = PHI %1, %bb.1, %0, %bb.0
B %bb.4
bb.3:
B %bb.3
bb.4:
%3:gpr32 = PHI %2, %bb.2
CBNZW %2, %bb.5
bb.5:
...
|
