File: 2004-02-23-ShiftShiftOverflow.ll

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llvm-toolchain-4.0 1%3A4.0.1-10~deb9u2
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; RUN: opt < %s -instcombine -S | not grep 34

define i32 @test(i32 %X) {
        ; Do not fold into shr X, 34, as this uses undefined behavior!
        %Y = ashr i32 %X, 17            ; <i32> [#uses=1]
        %Z = ashr i32 %Y, 17            ; <i32> [#uses=1]
        ret i32 %Z
}

define i32 @test2(i32 %X) {
        ; Do not fold into shl X, 34, as this uses undefined behavior!
        %Y = shl i32 %X, 17             ; <i32> [#uses=1]
        %Z = shl i32 %Y, 17             ; <i32> [#uses=1]
        ret i32 %Z
}