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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
--- |
@g = external hidden unnamed_addr global i32, align 4
define void @not_necessarily_equiv_loads() { ret void }
define void @invariant_loads() { ret void }
define void @both_have_to_be_invariant() { ret void }
...
---
name: not_necessarily_equiv_loads
tracksRegLiveness: true
machineFunctionInfo: {}
body: |
bb.0:
; %load1 || %load2 == %load1 is not necessarily true, even though they
; both load from the same address. Whatever is in that address may be
; changed by another instruction which appears between them.
;
; Check that we don't remove the G_OR.
; CHECK-LABEL: name: not_necessarily_equiv_loads
; CHECK: %ptr:_(p0) = G_GLOBAL_VALUE @g
; CHECK: %load1:_(s32) = G_LOAD %ptr(p0) :: (load (s32) from @g)
; CHECK: %load2:_(s32) = G_LOAD %ptr(p0) :: (load (s32) from @g)
; CHECK: %or:_(s32) = G_OR %load2, %load1
; CHECK: G_STORE %or(s32), %ptr(p0) :: (store (s32) into @g)
; CHECK: RET_ReallyLR
%ptr:_(p0) = G_GLOBAL_VALUE @g
%load1:_(s32) = G_LOAD %ptr(p0) :: (load (s32) from @g)
%load2:_(s32) = G_LOAD %ptr(p0) :: (load (s32) from @g)
%or:_(s32) = G_OR %load2, %load1
G_STORE %or(s32), %ptr(p0) :: (store (s32) into @g)
RET_ReallyLR
...
---
name: invariant_loads
tracksRegLiveness: true
machineFunctionInfo: {}
body: |
bb.0:
; %load1 || %load2 == %load1 is fine here, because the loads are invariant.
; CHECK-LABEL: name: invariant_loads
; CHECK: %ptr:_(p0) = G_GLOBAL_VALUE @g
; CHECK: %load2:_(s32) = G_LOAD %ptr(p0) :: (dereferenceable invariant load (s32) from @g)
; CHECK: G_STORE %load2(s32), %ptr(p0) :: (store (s32) into @g)
; CHECK: RET_ReallyLR
%ptr:_(p0) = G_GLOBAL_VALUE @g
%load1:_(s32) = G_LOAD %ptr(p0) :: (dereferenceable invariant load (s32) from @g)
%load2:_(s32) = G_LOAD %ptr(p0) :: (dereferenceable invariant load (s32) from @g)
%or:_(s32) = G_OR %load2, %load1
G_STORE %or(s32), %ptr(p0) :: (store (s32) into @g)
RET_ReallyLR
...
---
name: both_have_to_be_invariant
tracksRegLiveness: true
machineFunctionInfo: {}
body: |
bb.0:
; We shouldn't combine here, because the loads both have to be invariant.
; CHECK-LABEL: name: both_have_to_be_invariant
; CHECK: %ptr:_(p0) = G_GLOBAL_VALUE @g
; CHECK: %load1:_(s32) = G_LOAD %ptr(p0) :: (dereferenceable invariant load (s32) from @g)
; CHECK: %load2:_(s32) = G_LOAD %ptr(p0) :: (dereferenceable load (s32) from @g)
; CHECK: %or:_(s32) = G_OR %load2, %load1
; CHECK: G_STORE %or(s32), %ptr(p0) :: (store (s32) into @g)
; CHECK: RET_ReallyLR
%ptr:_(p0) = G_GLOBAL_VALUE @g
%load1:_(s32) = G_LOAD %ptr(p0) :: (dereferenceable invariant load (s32) from @g)
%load2:_(s32) = G_LOAD %ptr(p0) :: (dereferenceable load (s32) from @g)
%or:_(s32) = G_OR %load2, %load1
G_STORE %or(s32), %ptr(p0) :: (store (s32) into @g)
RET_ReallyLR
...
|
