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; ModuleID = 'test1.c'
; RUN: opt -S -instcombine < %s | FileCheck %s
target triple = "x86_64-apple-macosx10.6.6"
define zeroext i16 @foo(i32 %on_off, i16* %puls) nounwind uwtable ssp {
entry:
%on_off.addr = alloca i32, align 4
%puls.addr = alloca i16*, align 8
%a = alloca i32, align 4
store i32 %on_off, i32* %on_off.addr, align 4
store i16* %puls, i16** %puls.addr, align 8
%tmp = load i32* %on_off.addr, align 4
; CHECK-NOT: sub
; CHECK-NOT: mul
; (1 - %tmp) * (-2) -> (%tmp - 1) * 2
%sub = sub i32 1, %tmp
%mul = mul i32 %sub, -2
; CHECK: shl
; CHECK-NEXT: add
store i32 %mul, i32* %a, align 4
%tmp1 = load i32* %a, align 4
%conv = trunc i32 %tmp1 to i16
ret i16 %conv
}
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