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; RUN: opt -basicaa -gvn -S < %s | FileCheck %s
target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64"
target triple = "x86_64-apple-macosx10.7.0"
@x = common global i32 0, align 4
@y = common global i32 0, align 4
; GVN across unordered store (allowed)
define i32 @test1() nounwind uwtable ssp {
; CHECK-LABEL: test1
; CHECK: add i32 %x, %x
entry:
%x = load i32, i32* @y
store atomic i32 %x, i32* @x unordered, align 4
%y = load i32, i32* @y
%z = add i32 %x, %y
ret i32 %z
}
; GVN across unordered load (allowed)
define i32 @test3() nounwind uwtable ssp {
; CHECK-LABEL: test3
; CHECK: add i32 %x, %x
entry:
%x = load i32, i32* @y
%y = load atomic i32, i32* @x unordered, align 4
%z = load i32, i32* @y
%a = add i32 %x, %z
%b = add i32 %y, %a
ret i32 %b
}
; GVN load to unordered load (allowed)
define i32 @test5() nounwind uwtable ssp {
; CHECK-LABEL: test5
; CHECK: add i32 %x, %x
entry:
%x = load atomic i32, i32* @x unordered, align 4
%y = load i32, i32* @x
%z = add i32 %x, %y
ret i32 %z
}
; GVN unordered load to load (unordered load must not be removed)
define i32 @test6() nounwind uwtable ssp {
; CHECK-LABEL: test6
; CHECK: load atomic i32, i32* @x unordered
entry:
%x = load i32, i32* @x
%x2 = load atomic i32, i32* @x unordered, align 4
%x3 = add i32 %x, %x2
ret i32 %x3
}
; GVN across release-acquire pair (forbidden)
define i32 @test7() nounwind uwtable ssp {
; CHECK-LABEL: test7
; CHECK: add i32 %x, %y
entry:
%x = load i32, i32* @y
store atomic i32 %x, i32* @x release, align 4
%w = load atomic i32, i32* @x acquire, align 4
%y = load i32, i32* @y
%z = add i32 %x, %y
ret i32 %z
}
; GVN across monotonic store (allowed)
define i32 @test9() nounwind uwtable ssp {
; CHECK-LABEL: test9
; CHECK: add i32 %x, %x
entry:
%x = load i32, i32* @y
store atomic i32 %x, i32* @x monotonic, align 4
%y = load i32, i32* @y
%z = add i32 %x, %y
ret i32 %z
}
; GVN of an unordered across monotonic load (not allowed)
define i32 @test10() nounwind uwtable ssp {
; CHECK-LABEL: test10
; CHECK: add i32 %x, %y
entry:
%x = load atomic i32, i32* @y unordered, align 4
%clobber = load atomic i32, i32* @x monotonic, align 4
%y = load atomic i32, i32* @y monotonic, align 4
%z = add i32 %x, %y
ret i32 %z
}
define i32 @PR22708(i1 %flag) {
; CHECK-LABEL: PR22708
entry:
br i1 %flag, label %if.then, label %if.end
if.then:
store i32 43, i32* @y, align 4
; CHECK: store i32 43, i32* @y, align 4
br label %if.end
if.end:
load atomic i32, i32* @x acquire, align 4
%load = load i32, i32* @y, align 4
; CHECK: load atomic i32, i32* @x acquire, align 4
; CHECK: load i32, i32* @y, align 4
ret i32 %load
}
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