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; RUN: opt -S -instcombine < %s | FileCheck %s
; https://llvm.org/bugs/show_bug.cgi?id=25900
; An arithmetic shift right of a power of two is not a power
; of two if the original value is the sign bit. Therefore,
; we can't transform the sdiv into a udiv.
define i32 @pr25900(i32 %d) {
%and = and i32 %d, -2147483648
; The next 3 lines prevent another fold from masking the bug.
%ext = zext i32 %and to i64
%or = or i64 %ext, 4294967296
%trunc = trunc i64 %or to i32
%ashr = ashr exact i32 %trunc, 31
%div = sdiv i32 4, %ashr
ret i32 %div
; CHECK: sdiv
}
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