1 /* $NetBSD: math.c,v 1.1.1.1 2018/08/16 18:17:47 jmcneill Exp $ */ 2 3 /* 4 * Copright (C) 2014 Linaro Ltd. 5 * Author: Ard Biesheuvel <ard.biesheuvel@linaro.org> 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice and this list of conditions, without modification. 12 * 2. The name of the author may not be used to endorse or promote products 13 * derived from this software without specific prior written permission. 14 * 15 * Alternatively, this software may be distributed under the terms of the 16 * GNU General Public License as published by the Free Software Foundation; 17 * either version 2 of the License, or (at your option) any later version. 18 */ 19 20 #include "lib.h" 21 22 UINT64 23 LShiftU64 ( 24 IN UINT64 Operand, 25 IN UINTN Count 26 ) 27 // Left shift 64bit by 32bit and get a 64bit result 28 { 29 return Operand << Count; 30 } 31 32 UINT64 33 RShiftU64 ( 34 IN UINT64 Operand, 35 IN UINTN Count 36 ) 37 // Right shift 64bit by 32bit and get a 64bit result 38 { 39 return Operand >> Count; 40 } 41 42 43 UINT64 44 MultU64x32 ( 45 IN UINT64 Multiplicand, 46 IN UINTN Multiplier 47 ) 48 // Multiple 64bit by 32bit and get a 64bit result 49 { 50 return Multiplicand * Multiplier; 51 } 52 53 UINT64 54 DivU64x32 ( 55 IN UINT64 Dividend, 56 IN UINTN Divisor, 57 OUT UINTN *Remainder OPTIONAL 58 ) 59 // divide 64bit by 32bit and get a 64bit result 60 // N.B. only works for 31bit divisors!! 61 { 62 if (Remainder) 63 *Remainder = Dividend % Divisor; 64 return Dividend / Divisor; 65 } 66