; ModuleID = 'test1.c' ; RUN: opt -S -instcombine < %s | FileCheck %s target triple = "x86_64-apple-macosx10.6.6" define zeroext i16 @foo1(i32 %on_off) nounwind uwtable ssp { entry: %on_off.addr = alloca i32, align 4 %a = alloca i32, align 4 store i32 %on_off, i32* %on_off.addr, align 4 %tmp = load i32* %on_off.addr, align 4 %sub = sub i32 1, %tmp ; CHECK-NOT: mul i32 %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 } define zeroext i16 @foo2(i32 %on_off, i32 %q) nounwind uwtable ssp { entry: %on_off.addr = alloca i32, align 4 %q.addr = alloca i32, align 4 %a = alloca i32, align 4 store i32 %on_off, i32* %on_off.addr, align 4 store i32 %q, i32* %q.addr, align 4 %tmp = load i32* %q.addr, align 4 %tmp1 = load i32* %on_off.addr, align 4 %sub = sub i32 %tmp, %tmp1 ; CHECK-NOT: mul i32 %mul = mul i32 %sub, -4 ; CHECK: sub i32 ; CHECK-NEXT: shl store i32 %mul, i32* %a, align 4 %tmp2 = load i32* %a, align 4 %conv = trunc i32 %tmp2 to i16 ret i16 %conv } define zeroext i16 @foo3(i32 %on_off) nounwind uwtable ssp { entry: %on_off.addr = alloca i32, align 4 %a = alloca i32, align 4 store i32 %on_off, i32* %on_off.addr, align 4 %tmp = load i32* %on_off.addr, align 4 %sub = sub i32 7, %tmp ; CHECK-NOT: mul i32 %mul = mul i32 %sub, -4 ; 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 }