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1//===-- ashlti3.c - Implement __ashlti3 -----------------------------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8//9// This file implements __ashlti3 for the compiler_rt library.10//11//===----------------------------------------------------------------------===//12 13#include "int_lib.h"14 15#ifdef CRT_HAS_128BIT16 17// Returns: a << b18 19// Precondition: 0 <= b < bits_in_tword20 21COMPILER_RT_ABI ti_int __ashlti3(ti_int a, int b) {22 const int bits_in_dword = (int)(sizeof(di_int) * CHAR_BIT);23 twords input;24 twords result;25 input.all = a;26 if (b & bits_in_dword) /* bits_in_dword <= b < bits_in_tword */ {27 result.s.low = 0;28 result.s.high = input.s.low << (b - bits_in_dword);29 } else /* 0 <= b < bits_in_dword */ {30 if (b == 0)31 return a;32 result.s.low = input.s.low << b;33 result.s.high =34 ((du_int)input.s.high << b) | (input.s.low >> (bits_in_dword - b));35 }36 return result.all;37}38 39#endif // CRT_HAS_128BIT40