| // Copyright (c) 2015, the Dart project authors. Please see the AUTHORS file |
| // for details. All rights reserved. Use of this source code is governed by a |
| // BSD-style license that can be found in the LICENSE file. |
| |
| /// A bitmask that limits an integer to 32 bits. |
| const mask32 = 0xFFFFFFFF; |
| |
| /// The number of bits in a byte. |
| const bitsPerByte = 8; |
| |
| /// The number of bytes in a 32-bit word. |
| const bytesPerWord = 4; |
| |
| /// Adds [x] and [y] with 32-bit overflow semantics. |
| int add32(int x, int y) => (x + y) & mask32; |
| |
| /// Bitwise rotates [val] to the left by [shift], obeying 32-bit overflow |
| /// semantics. |
| int rotl32(int val, int shift) { |
| var modShift = shift & 31; |
| return ((val << modShift) & mask32) | ((val & mask32) >> (32 - modShift)); |
| } |
