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; XFAIL: *
; RUN: opt -S -passes=dse < %s | FileCheck %s
; We DSE stack alloc'ed and byval locations, in the presence of fences.
; Fence does not make an otherwise thread local store visible.
; Right now the DSE in presence of fence is only done in end blocks (with no successors),
; but the same logic applies to other basic blocks as well.
; The store to %addr.i can be removed since it is a byval attribute
define void @test3(ptr byval(i32) %addr.i) {
; CHECK-LABEL: @test3
; CHECK-NOT: store
; CHECK: fence
; CHECK: ret
store i32 5, ptr %addr.i, align 4
fence release
ret void
}
declare void @foo(ptr nocapture %p)
declare noalias ptr @malloc(i32)
; DSE of stores in locations allocated through library calls.
define void @test_nocapture() {
; CHECK-LABEL: @test_nocapture
; CHECK: malloc
; CHECK: foo
; CHECK-NOT: store
; CHECK: fence
%m = call ptr @malloc(i32 24)
call void @foo(ptr %m)
store i8 4, ptr %m
fence release
ret void
}
; This is a full fence, but it does not make a thread local store visible.
; We can DSE the store in presence of the fence.
define void @fence_seq_cst() {
; CHECK-LABEL: @fence_seq_cst
; CHECK-NEXT: fence seq_cst
; CHECK-NEXT: ret void
%P1 = alloca i32
store i32 0, ptr %P1, align 4
fence seq_cst
store i32 4, ptr %P1, align 4
ret void
}
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