test/Transforms/InstCombine/shift-sra.ll


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; RUN: opt %s -instcombine | llvm-dis | \
; RUN:    grep {lshr i32} | count 2
; RUN: opt %s -instcombine | llvm-dis | not grep ashr


define i32 @test1(i32 %X, i8 %A) {
        %shift.upgrd.1 = zext i8 %A to i32              ; <i32> [#uses=1]
        ; can be logical shift.
        %Y = ashr i32 %X, %shift.upgrd.1                ; <i32> [#uses=1]
        %Z = and i32 %Y, 1              ; <i32> [#uses=1]
        ret i32 %Z
}

define i32 @test2(i8 %tmp) {
        %tmp3 = zext i8 %tmp to i32             ; <i32> [#uses=1]
        %tmp4 = add i32 %tmp3, 7                ; <i32> [#uses=1]
        %tmp5 = ashr i32 %tmp4, 3               ; <i32> [#uses=1]
        ret i32 %tmp5
}