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|
; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt -passes=dse -S %s | FileCheck %s
; Both the stores in %then and %else can be eliminated by translating %p
; through the phi.
define void @memoryphi_translate_1(i1 %c) {
; CHECK-LABEL: @memoryphi_translate_1(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[A_1:%.*]] = alloca i8, align 1
; CHECK-NEXT: [[A_2:%.*]] = alloca i8, align 1
; CHECK-NEXT: br i1 [[C:%.*]], label [[THEN:%.*]], label [[ELSE:%.*]]
; CHECK: then:
; CHECK-NEXT: br label [[END:%.*]]
; CHECK: else:
; CHECK-NEXT: br label [[END]]
; CHECK: end:
; CHECK-NEXT: [[P:%.*]] = phi ptr [ [[A_1]], [[THEN]] ], [ [[A_2]], [[ELSE]] ]
; CHECK-NEXT: store i8 10, ptr [[P]], align 1
; CHECK-NEXT: ret void
;
entry:
%a.1 = alloca i8
%a.2 = alloca i8
br i1 %c, label %then, label %else
then:
store i8 0, ptr %a.1
br label %end
else:
store i8 9, ptr %a.2
br label %end
end:
%p = phi ptr [ %a.1, %then ], [ %a.2, %else ]
store i8 10, ptr %p
ret void
}
; The store in %else can be eliminated by translating %p through the phi.
; The store in %then cannot be eliminated, because %a.1 is read before the final
; store.
define i8 @memoryphi_translate_2(i1 %c) {
; CHECK-LABEL: @memoryphi_translate_2(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[A_1:%.*]] = alloca i8, align 1
; CHECK-NEXT: [[A_2:%.*]] = alloca i8, align 1
; CHECK-NEXT: br i1 [[C:%.*]], label [[THEN:%.*]], label [[ELSE:%.*]]
; CHECK: then:
; CHECK-NEXT: store i8 0, ptr [[A_1]], align 1
; CHECK-NEXT: br label [[END:%.*]]
; CHECK: else:
; CHECK-NEXT: br label [[END]]
; CHECK: end:
; CHECK-NEXT: [[P:%.*]] = phi ptr [ [[A_1]], [[THEN]] ], [ [[A_2]], [[ELSE]] ]
; CHECK-NEXT: [[L:%.*]] = load i8, ptr [[A_1]], align 1
; CHECK-NEXT: store i8 10, ptr [[P]], align 1
; CHECK-NEXT: ret i8 [[L]]
;
entry:
%a.1 = alloca i8
%a.2 = alloca i8
br i1 %c, label %then, label %else
then:
store i8 0, ptr %a.1
br label %end
else:
store i8 9, ptr %a.2
br label %end
end:
%p = phi ptr [ %a.1, %then ], [ %a.2, %else ]
%l = load i8, ptr %a.1
store i8 10, ptr %p
ret i8 %l
}
; The store in %then can be eliminated by translating %p through the phi.
; The store in %else cannot be eliminated, because %a.2 is read before the final
; store.
define i8 @memoryphi_translate_3(i1 %c) {
; CHECK-LABEL: @memoryphi_translate_3(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[A_1:%.*]] = alloca i8, align 1
; CHECK-NEXT: [[A_2:%.*]] = alloca i8, align 1
; CHECK-NEXT: br i1 [[C:%.*]], label [[THEN:%.*]], label [[ELSE:%.*]]
; CHECK: then:
; CHECK-NEXT: br label [[END:%.*]]
; CHECK: else:
; CHECK-NEXT: store i8 9, ptr [[A_2]], align 1
; CHECK-NEXT: br label [[END]]
; CHECK: end:
; CHECK-NEXT: [[P:%.*]] = phi ptr [ [[A_1]], [[THEN]] ], [ [[A_2]], [[ELSE]] ]
; CHECK-NEXT: [[L:%.*]] = load i8, ptr [[A_2]], align 1
; CHECK-NEXT: store i8 10, ptr [[P]], align 1
; CHECK-NEXT: ret i8 [[L]]
;
entry:
%a.1 = alloca i8
%a.2 = alloca i8
br i1 %c, label %then, label %else
then:
store i8 0, ptr %a.1
br label %end
else:
store i8 9, ptr %a.2
br label %end
end:
%p = phi ptr [ %a.1, %then ], [ %a.2, %else ]
%l = load i8, ptr %a.2
store i8 10, ptr %p
ret i8 %l
}
; No stores can be eliminated, because there's a load from the phi.
define i8 @memoryphi_translate_4(i1 %c) {
; CHECK-LABEL: @memoryphi_translate_4(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[A_1:%.*]] = alloca i8, align 1
; CHECK-NEXT: [[A_2:%.*]] = alloca i8, align 1
; CHECK-NEXT: br i1 [[C:%.*]], label [[THEN:%.*]], label [[ELSE:%.*]]
; CHECK: then:
; CHECK-NEXT: store i8 0, ptr [[A_1]], align 1
; CHECK-NEXT: br label [[END:%.*]]
; CHECK: else:
; CHECK-NEXT: store i8 9, ptr [[A_2]], align 1
; CHECK-NEXT: br label [[END]]
; CHECK: end:
; CHECK-NEXT: [[P:%.*]] = phi ptr [ [[A_1]], [[THEN]] ], [ [[A_2]], [[ELSE]] ]
; CHECK-NEXT: [[L:%.*]] = load i8, ptr [[P]], align 1
; CHECK-NEXT: store i8 10, ptr [[P]], align 1
; CHECK-NEXT: ret i8 [[L]]
;
entry:
%a.1 = alloca i8
%a.2 = alloca i8
br i1 %c, label %then, label %else
then:
store i8 0, ptr %a.1
br label %end
else:
store i8 9, ptr %a.2
br label %end
end:
%p = phi ptr [ %a.1, %then ], [ %a.2, %else ]
%l = load i8, ptr %p
store i8 10, ptr %p
ret i8 %l
}
; TODO: The store in %entry can be removed by translating %p through the phi.
define void @memoryphi_translate_5(i1 %cond) {
; CHECK-LABEL: @memoryphi_translate_5(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[A:%.*]] = alloca i8, align 1
; CHECK-NEXT: [[B:%.*]] = alloca i8, align 1
; CHECK-NEXT: store i8 0, ptr [[A]], align 1
; CHECK-NEXT: br i1 [[COND:%.*]], label [[COND_TRUE:%.*]], label [[COND_END:%.*]]
; CHECK: cond.true:
; CHECK-NEXT: br label [[COND_END]]
; CHECK: cond.end:
; CHECK-NEXT: [[P:%.*]] = phi ptr [ [[B]], [[COND_TRUE]] ], [ [[A]], [[ENTRY:%.*]] ]
; CHECK-NEXT: store i8 0, ptr [[P]], align 1
; CHECK-NEXT: call void @use(ptr [[P]])
; CHECK-NEXT: ret void
;
entry:
%a = alloca i8
%b = alloca i8
%c = alloca i8
store i8 0, ptr %a
br i1 %cond, label %cond.true, label %cond.end
cond.true:
store i8 0, ptr %c
br label %cond.end
cond.end:
%p = phi ptr [ %b, %cond.true ], [ %a, %entry ]
store i8 0, ptr %p
call void @use(ptr %p)
ret void
}
; TODO: The store in %entry can be removed by translating %p through the phi.
; Same as @memoryphi_translate_5, but without stores in %cond.true, so there
; is no MemoryPhi.
define void @translate_without_memoryphi_1(i1 %cond) {
; CHECK-LABEL: @translate_without_memoryphi_1(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[A:%.*]] = alloca i8, align 1
; CHECK-NEXT: [[B:%.*]] = alloca i8, align 1
; CHECK-NEXT: store i8 0, ptr [[A]], align 1
; CHECK-NEXT: br i1 [[COND:%.*]], label [[COND_TRUE:%.*]], label [[COND_END:%.*]]
; CHECK: cond.true:
; CHECK-NEXT: br label [[COND_END]]
; CHECK: cond.end:
; CHECK-NEXT: [[P:%.*]] = phi ptr [ [[B]], [[COND_TRUE]] ], [ [[A]], [[ENTRY:%.*]] ]
; CHECK-NEXT: store i8 0, ptr [[P]], align 1
; CHECK-NEXT: call void @use(ptr [[P]])
; CHECK-NEXT: ret void
;
entry:
%a = alloca i8
%b = alloca i8
store i8 0, ptr %a
br i1 %cond, label %cond.true, label %cond.end
cond.true:
br label %cond.end
cond.end:
%p = phi ptr [ %b, %cond.true ], [ %a, %entry ]
store i8 0, ptr %p
call void @use(ptr %p)
ret void
}
; In the test, translating through the phi results in a null address. Make sure
; this does not cause a crash.
define void @test_trans_null(i1 %c, ptr %ptr) {
; CHECK-LABEL: @test_trans_null(
; CHECK-NEXT: entry:
; CHECK-NEXT: br i1 [[C:%.*]], label [[THEN:%.*]], label [[ELSE:%.*]]
; CHECK: then:
; CHECK-NEXT: br label [[EXIT:%.*]]
; CHECK: else:
; CHECK-NEXT: call void @fn()
; CHECK-NEXT: [[GEP_1:%.*]] = getelementptr inbounds i16, ptr undef, i64 2
; CHECK-NEXT: store i16 8, ptr [[GEP_1]], align 2
; CHECK-NEXT: br label [[EXIT]]
; CHECK: exit:
; CHECK-NEXT: [[P:%.*]] = phi ptr [ [[PTR:%.*]], [[THEN]] ], [ undef, [[ELSE]] ]
; CHECK-NEXT: [[GEP_2:%.*]] = getelementptr inbounds i16, ptr [[P]], i64 2
; CHECK-NEXT: store i16 8, ptr [[GEP_2]], align 2
; CHECK-NEXT: ret void
;
entry:
br i1 %c, label %then, label %else
then:
br label %exit
else:
call void @fn()
%gep.1 = getelementptr inbounds i16, ptr undef, i64 2
store i16 8, ptr %gep.1, align 2
br label %exit
exit:
%p = phi ptr [ %ptr, %then ], [ undef, %else ]
%gep.2 = getelementptr inbounds i16, ptr %p, i64 2
store i16 8, ptr %gep.2, align 2
ret void
}
declare void @use(ptr)
declare void @fn()
|
