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|
# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py
# RUN: llc -mtriple aarch64 -run-pass=aarch64-prelegalizer-combiner -verify-machineinstrs %s -o - | FileCheck %s
--- |
declare void @foo()
define void @self() { ret void }
define void @self_with_copy() { ret void }
define void @self_not_equivalent_overwrite_w0() { ret void }
define void @self_not_equivalent_overwrite_w0_implicit() { ret void }
define void @self_not_equivalent_different_copies() { ret void }
define void @self_with_assert_zext() { ret void }
...
---
name: self
tracksRegLiveness: true
body: |
bb.0:
liveins: $w0, $w1
; Optimize (cond ? %a : %a) -> %a
; CHECK-LABEL: name: self
; CHECK: liveins: $w0, $w1
; CHECK: %a:_(s32) = COPY $w0
; CHECK: $w0 = COPY %a(s32)
; CHECK: RET_ReallyLR implicit $w0
%a:_(s32) = COPY $w0
%cond_wide:gpr(s32) = COPY $w1
%cond:gpr(s1) = G_TRUNC %cond_wide(s32)
%select:_(s32) = G_SELECT %cond(s1), %a, %a
$w0 = COPY %select(s32)
RET_ReallyLR implicit $w0
...
---
name: self_with_copy
tracksRegLiveness: true
body: |
bb.0:
liveins: $w0, $w1
; Optimize (cond ? %a : %b) -> %a
;
; This shows that we are looking through copies correctly and deduce that
; %b is a copy from %a.
;
; CHECK-LABEL: name: self_with_copy
; CHECK: liveins: $w0, $w1
; CHECK: %a:_(s32) = COPY $w0
; CHECK: $w0 = COPY %a(s32)
; CHECK: RET_ReallyLR implicit $w0
%a:_(s32) = COPY $w0
%b:_(s32) = COPY %a
%cond_wide:gpr(s32) = COPY $w1
%cond:gpr(s1) = G_TRUNC %cond_wide(s32)
%select:_(s32) = G_SELECT %cond(s1), %a, %b
$w0 = COPY %select(s32)
RET_ReallyLR implicit $w0
...
---
name: self_not_equivalent_overwrite_w0
tracksRegLiveness: true
body: |
bb.0:
liveins: $w0, $w1
;
; $w0 is overwritten by a copy from $w1, so the copies for %a and %b are
; not the same.
;
; CHECK-LABEL: name: self_not_equivalent_overwrite_w0
; CHECK: liveins: $w0, $w1
; CHECK: %a:_(s32) = COPY $w0
; CHECK: $w0 = COPY $w1
; CHECK: %b:_(s32) = COPY $w0
; CHECK: %cond_wide:gpr(s32) = COPY $w1
; CHECK: %cond:gpr(s1) = G_TRUNC %cond_wide(s32)
; CHECK: %select:_(s32) = G_SELECT %cond(s1), %a, %b
; CHECK: $w0 = COPY %select(s32)
; CHECK: RET_ReallyLR implicit $w0
%a:_(s32) = COPY $w0
$w0 = COPY $w1
%b:_(s32) = COPY $w0
%cond_wide:gpr(s32) = COPY $w1
%cond:gpr(s1) = G_TRUNC %cond_wide(s32)
%select:_(s32) = G_SELECT %cond(s1), %a, %b
$w0 = COPY %select(s32)
RET_ReallyLR implicit $w0
...
---
name: self_not_equivalent_overwrite_w0_implicit
tracksRegLiveness: true
body: |
bb.0:
liveins: $w0, $w1
;
; $w0 is overwritten by a call which defines it implicitly, so the copies
; are not the same.
;
; CHECK-LABEL: name: self_not_equivalent_overwrite_w0_implicit
; CHECK: liveins: $w0, $w1
; CHECK: %a:_(s32) = COPY $w0
; CHECK: BL @foo, implicit-def $w0
; CHECK: %b:_(s32) = COPY $w0
; CHECK: %cond_wide:gpr(s32) = COPY $w1
; CHECK: %cond:gpr(s1) = G_TRUNC %cond_wide(s32)
; CHECK: %select:_(s32) = G_SELECT %cond(s1), %a, %b
; CHECK: $w0 = COPY %select(s32)
; CHECK: RET_ReallyLR implicit $w0
%a:_(s32) = COPY $w0
BL @foo, implicit-def $w0
%b:_(s32) = COPY $w0
%cond_wide:gpr(s32) = COPY $w1
%cond:gpr(s1) = G_TRUNC %cond_wide(s32)
%select:_(s32) = G_SELECT %cond(s1), %a, %b
$w0 = COPY %select(s32)
RET_ReallyLR implicit $w0
...
---
name: self_not_equivalent_different_copies
tracksRegLiveness: true
body: |
bb.0:
liveins: $w0, $w1
; In this case, the copies are not equivalent, so there is no optimization.
;
; CHECK-LABEL: name: self_not_equivalent_different_copies
; CHECK: liveins: $w0, $w1
; CHECK: %a:_(s32) = COPY $w0
; CHECK: %b:_(s32) = COPY $w1
; CHECK: %cond_wide:gpr(s32) = COPY $w1
; CHECK: %cond:gpr(s1) = G_TRUNC %cond_wide(s32)
; CHECK: %select:_(s32) = G_SELECT %cond(s1), %a, %b
; CHECK: $w0 = COPY %select(s32)
; CHECK: RET_ReallyLR implicit $w0
%a:_(s32) = COPY $w0
%b:_(s32) = COPY $w1
%c:_(s32) = COPY %b
%cond_wide:gpr(s32) = COPY $w1
%cond:gpr(s1) = G_TRUNC %cond_wide(s32)
%select:_(s32) = G_SELECT %cond(s1), %a, %c
$w0 = COPY %select(s32)
RET_ReallyLR implicit $w0
...
---
name: self_with_assert_zext
tracksRegLiveness: true
body: |
bb.0:
liveins: $w0, $w1
; We should walk through G_ASSERT_ZEXT as if it's a copy, and remove the
; G_SELECT.
;
; CHECK-LABEL: name: self_with_assert_zext
; CHECK: liveins: $w0, $w1
; CHECK: %a:_(s32) = COPY $w0
; CHECK: %a_assert_zext:_(s32) = G_ASSERT_ZEXT %a, 16
; CHECK: $w0 = COPY %a_assert_zext(s32)
; CHECK: RET_ReallyLR implicit $w0
%a:_(s32) = COPY $w0
%a_assert_zext:_(s32) = G_ASSERT_ZEXT %a, 16
%b:_(s32) = COPY %a_assert_zext
%cond_wide:gpr(s32) = COPY $w1
%cond:gpr(s1) = G_TRUNC %cond_wide(s32)
%select:_(s32) = G_SELECT %cond(s1), %a_assert_zext, %b
$w0 = COPY %select(s32)
RET_ReallyLR implicit $w0
|
