test/Transforms/InstCombine/cast2.ll


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; Tests to make sure elimination of casts is working correctly
; RUN: opt < %s -instcombine -S | FileCheck %s

define i16 @test1(i16 %a) {
        %tmp = zext i16 %a to i32               ; <i32> [#uses=2]
        %tmp21 = lshr i32 %tmp, 8               ; <i32> [#uses=1]
        %tmp5 = shl i32 %tmp, 8         ; <i32> [#uses=1]
        %tmp.upgrd.32 = or i32 %tmp21, %tmp5            ; <i32> [#uses=1]
        %tmp.upgrd.3 = trunc i32 %tmp.upgrd.32 to i16           ; <i16> [#uses=1]
        ret i16 %tmp.upgrd.3
; CHECK: %tmp.upgrd.32 = call i16 @llvm.bswap.i16(i16 %a)
; CHECK: ret i16 %tmp.upgrd.32
}

define i16 @test2(i16 %a) {
        %tmp = zext i16 %a to i32               ; <i32> [#uses=2]
        %tmp21 = lshr i32 %tmp, 9               ; <i32> [#uses=1]
        %tmp5 = shl i32 %tmp, 8         ; <i32> [#uses=1]
        %tmp.upgrd.32 = or i32 %tmp21, %tmp5            ; <i32> [#uses=1]
        %tmp.upgrd.3 = trunc i32 %tmp.upgrd.32 to i16           ; <i16> [#uses=1]
        ret i16 %tmp.upgrd.3
; CHECK: %tmp21 = lshr i16 %a, 9
; CHECK: %tmp5 = shl i16 %a, 8
; CHECK: %tmp.upgrd.32 = or i16 %tmp21, %tmp5
; CHECK: ret i16 %tmp.upgrd.32
}

; PR1263
define i32* @test3(i32* %tmp1) {
        %tmp64 = bitcast i32* %tmp1 to { i32 }*         ; <{ i32 }*> [#uses=1]
        %tmp65 = getelementptr { i32 }* %tmp64, i32 0, i32 0            ; <i32*> [#uses=1]
        ret i32* %tmp65
; CHECK: ret i32* %tmp1
}