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; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt -S -passes=early-cse -earlycse-debug-hash < %s | FileCheck %s --check-prefixes=CHECK,NO-MSSA
; RUN: opt -S -passes='early-cse<memssa>' < %s | FileCheck %s --check-prefixes=CHECK,MSSA
@var = global i32 undef
declare void @foo() nounwind
define void @test() {
; CHECK-LABEL: @test(
; CHECK-NEXT: call void @foo() #[[ATTR1:[0-9]+]]
; CHECK-NEXT: store i32 2, ptr @var, align 4
; CHECK-NEXT: ret void
;
store i32 1, ptr @var
call void @foo() writeonly
store i32 2, ptr @var
ret void
}
declare void @writeonly_void() memory(write)
; Can CSE writeonly calls, including non-nounwind/willreturn.
define void @writeonly_cse() {
; CHECK-LABEL: @writeonly_cse(
; CHECK-NEXT: call void @writeonly_void()
; CHECK-NEXT: ret void
;
call void @writeonly_void()
call void @writeonly_void()
ret void
}
; Can CSE, loads do not matter.
define i32 @writeonly_cse_intervening_load(ptr %p) {
; CHECK-LABEL: @writeonly_cse_intervening_load(
; CHECK-NEXT: call void @writeonly_void()
; CHECK-NEXT: [[V:%.*]] = load i32, ptr [[P:%.*]], align 4
; CHECK-NEXT: ret i32 [[V]]
;
call void @writeonly_void()
%v = load i32, ptr %p
call void @writeonly_void()
ret i32 %v
}
; Cannot CSE, the store may be to the same memory.
define void @writeonly_cse_intervening_store(ptr %p) {
; CHECK-LABEL: @writeonly_cse_intervening_store(
; CHECK-NEXT: call void @writeonly_void()
; CHECK-NEXT: store i32 0, ptr [[P:%.*]], align 4
; CHECK-NEXT: call void @writeonly_void()
; CHECK-NEXT: ret void
;
call void @writeonly_void()
store i32 0, ptr %p
call void @writeonly_void()
ret void
}
; Can CSE, the store does not alias the writeonly call.
define void @writeonly_cse_intervening_noalias_store(ptr noalias %p) {
; NO-MSSA-LABEL: @writeonly_cse_intervening_noalias_store(
; NO-MSSA-NEXT: call void @writeonly_void()
; NO-MSSA-NEXT: store i32 0, ptr [[P:%.*]], align 4
; NO-MSSA-NEXT: call void @writeonly_void()
; NO-MSSA-NEXT: ret void
;
; MSSA-LABEL: @writeonly_cse_intervening_noalias_store(
; MSSA-NEXT: call void @writeonly_void()
; MSSA-NEXT: store i32 0, ptr [[P:%.*]], align 4
; MSSA-NEXT: ret void
;
call void @writeonly_void()
store i32 0, ptr %p
call void @writeonly_void()
ret void
}
; Cannot CSE loads across writeonly call.
define i32 @load_cse_across_writeonly(ptr %p) {
; CHECK-LABEL: @load_cse_across_writeonly(
; CHECK-NEXT: [[V1:%.*]] = load i32, ptr [[P:%.*]], align 4
; CHECK-NEXT: call void @writeonly_void()
; CHECK-NEXT: [[V2:%.*]] = load i32, ptr [[P]], align 4
; CHECK-NEXT: [[RES:%.*]] = sub i32 [[V1]], [[V2]]
; CHECK-NEXT: ret i32 [[RES]]
;
%v1 = load i32, ptr %p
call void @writeonly_void()
%v2 = load i32, ptr %p
%res = sub i32 %v1, %v2
ret i32 %res
}
; Can CSE loads across eliminated writeonly call.
define i32 @load_cse_across_csed_writeonly(ptr %p) {
; CHECK-LABEL: @load_cse_across_csed_writeonly(
; CHECK-NEXT: call void @writeonly_void()
; CHECK-NEXT: [[V2:%.*]] = load i32, ptr [[P:%.*]], align 4
; CHECK-NEXT: ret i32 0
;
call void @writeonly_void()
%v1 = load i32, ptr %p
call void @writeonly_void()
%v2 = load i32, ptr %p
%res = sub i32 %v1, %v2
ret i32 %res
}
declare i32 @writeonly(ptr %p) memory(write)
; Can CSE writeonly calls with arg and return.
define i32 @writeonly_ret_cse(ptr %p) {
; CHECK-LABEL: @writeonly_ret_cse(
; CHECK-NEXT: [[V2:%.*]] = call i32 @writeonly(ptr [[P:%.*]])
; CHECK-NEXT: ret i32 0
;
%v1 = call i32 @writeonly(ptr %p)
%v2 = call i32 @writeonly(ptr %p)
%res = sub i32 %v1, %v2
ret i32 %res
}
; Cannot CSE writeonly calls with different arguments.
define i32 @writeonly_different_args(ptr %p1, ptr %p2) {
; CHECK-LABEL: @writeonly_different_args(
; CHECK-NEXT: [[V1:%.*]] = call i32 @writeonly(ptr [[P1:%.*]])
; CHECK-NEXT: [[V2:%.*]] = call i32 @writeonly(ptr [[P2:%.*]])
; CHECK-NEXT: [[RES:%.*]] = sub i32 [[V1]], [[V2]]
; CHECK-NEXT: ret i32 [[RES]]
;
%v1 = call i32 @writeonly(ptr %p1)
%v2 = call i32 @writeonly(ptr %p2)
%res = sub i32 %v1, %v2
ret i32 %res
}
declare void @callee()
; These are weird cases where the same call is both readonly and writeonly
; based on call-site attributes. I believe this implies that both calls are
; actually readnone and safe to CSE, but leave them alone to be conservative.
define void @readonly_and_writeonly() {
; CHECK-LABEL: @readonly_and_writeonly(
; CHECK-NEXT: call void @callee() #[[ATTR2:[0-9]+]]
; CHECK-NEXT: call void @callee() #[[ATTR1]]
; CHECK-NEXT: ret void
;
call void @callee() memory(read)
call void @callee() memory(write)
ret void
}
define void @writeonly_and_readonly() {
; CHECK-LABEL: @writeonly_and_readonly(
; CHECK-NEXT: call void @callee() #[[ATTR1]]
; CHECK-NEXT: call void @callee() #[[ATTR2]]
; CHECK-NEXT: ret void
;
call void @callee() memory(write)
call void @callee() memory(read)
ret void
}
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