1// ====-- ashldi3.c - Implement __ashldi3 ---------------------------------===//
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-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This file implements __ashldi3 for the compiler_rt library.
10//
11//===----------------------------------------------------------------------===//
12
13#include "int_lib.h"
14
15// Returns: a << b
16
17// Precondition:  0 <= b < bits_in_dword
18
19COMPILER_RT_ABI di_int __ashldi3(di_int a, si_int b) {
20  const int bits_in_word = (int)(sizeof(si_int) * CHAR_BIT);
21  dwords input;
22  dwords result;
23  input.all = a;
24  if (b & bits_in_word) /* bits_in_word <= b < bits_in_dword */ {
25    result.s.low = 0;
26    result.s.high = input.s.low << (b - bits_in_word);
27  } else /* 0 <= b < bits_in_word */ {
28    if (b == 0)
29      return a;
30    result.s.low = input.s.low << b;
31    result.s.high = (input.s.high << b) | (input.s.low >> (bits_in_word - b));
32  }
33  return result.all;
34}
35
36#if defined(__ARM_EABI__)
37COMPILER_RT_ALIAS(__ashldi3, __aeabi_llsl)
38#endif
39