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; This file contains various testcases that require tracking whether bits are
; set or cleared by various instructions.
; RUN: opt %s -instcombine -instcombine -S |\
; RUN: not grep %ELIM
; Reduce down to a single XOR
define i32 @test3(i32 %B) {
%ELIMinc = and i32 %B, 1 ; <i32> [#uses=1]
%tmp.5 = xor i32 %ELIMinc, 1 ; <i32> [#uses=1]
%ELIM7 = and i32 %B, -2 ; <i32> [#uses=1]
%tmp.8 = or i32 %tmp.5, %ELIM7 ; <i32> [#uses=1]
ret i32 %tmp.8
}
; Finally, a bigger case where we chain things together. This corresponds to
; incrementing a single-bit bitfield, which should become just an xor.
define i32 @test4(i32 %B) {
%ELIM3 = shl i32 %B, 31 ; <i32> [#uses=1]
%ELIM4 = ashr i32 %ELIM3, 31 ; <i32> [#uses=1]
%inc = add i32 %ELIM4, 1 ; <i32> [#uses=1]
%ELIM5 = and i32 %inc, 1 ; <i32> [#uses=1]
%ELIM7 = and i32 %B, -2 ; <i32> [#uses=1]
%tmp.8 = or i32 %ELIM5, %ELIM7 ; <i32> [#uses=1]
ret i32 %tmp.8
}
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