quad.h revision 40874
1130803Smarcel/*- 2130803Smarcel * Copyright (c) 1992, 1993 3130803Smarcel * The Regents of the University of California. All rights reserved. 4130803Smarcel * 5130803Smarcel * This software was developed by the Computer Systems Engineering group 6130803Smarcel * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and 7130803Smarcel * contributed to Berkeley. 8130803Smarcel * 9130803Smarcel * Redistribution and use in source and binary forms, with or without 10130803Smarcel * modification, are permitted provided that the following conditions 11130803Smarcel * are met: 12130803Smarcel * 1. Redistributions of source code must retain the above copyright 13130803Smarcel * notice, this list of conditions and the following disclaimer. 14130803Smarcel * 2. Redistributions in binary form must reproduce the above copyright 15130803Smarcel * notice, this list of conditions and the following disclaimer in the 16130803Smarcel * documentation and/or other materials provided with the distribution. 17130803Smarcel * 3. All advertising materials mentioning features or use of this software 18130803Smarcel * must display the following acknowledgement: 19130803Smarcel * This product includes software developed by the University of 20130803Smarcel * California, Berkeley and its contributors. 21130803Smarcel * 4. Neither the name of the University nor the names of its contributors 22130803Smarcel * may be used to endorse or promote products derived from this software 23130803Smarcel * without specific prior written permission. 24130803Smarcel * 25130803Smarcel * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 26130803Smarcel * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 27130803Smarcel * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 28130803Smarcel * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 29130803Smarcel * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 30130803Smarcel * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 31130803Smarcel * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 32130803Smarcel * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 33130803Smarcel * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 34130803Smarcel * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 35130803Smarcel * SUCH DAMAGE. 36130803Smarcel * 37130803Smarcel * @(#)quad.h 8.1 (Berkeley) 6/4/93 38130803Smarcel * $Id: quad.h,v 1.6 1997/02/22 09:39:58 peter Exp $ 39130803Smarcel */ 40130803Smarcel 41130803Smarcel/* 42130803Smarcel * Quad arithmetic. 43130803Smarcel * 44130803Smarcel * This library makes the following assumptions: 45130803Smarcel * 46130803Smarcel * - The type long long (aka quad_t) exists. 47130803Smarcel * 48130803Smarcel * - A quad variable is exactly twice as long as `long'. 49130803Smarcel * 50130803Smarcel * - The machine's arithmetic is two's complement. 51130803Smarcel * 52130803Smarcel * This library can provide 128-bit arithmetic on a machine with 128-bit 53130803Smarcel * quads and 64-bit longs, for instance, or 96-bit arithmetic on machines 54130803Smarcel * with 48-bit longs. 55130803Smarcel */ 56130803Smarcel 57130803Smarcel#include <sys/cdefs.h> 58130803Smarcel#include <sys/types.h> 59130803Smarcel#include <limits.h> 60130803Smarcel 61130803Smarcel/* 62130803Smarcel * Depending on the desired operation, we view a `long long' (aka quad_t) in 63130803Smarcel * one or more of the following formats. 64130803Smarcel */ 65130803Smarcelunion uu { 66130803Smarcel quad_t q; /* as a (signed) quad */ 67130803Smarcel quad_t uq; /* as an unsigned quad */ 68130803Smarcel long sl[2]; /* as two signed longs */ 69130803Smarcel u_long ul[2]; /* as two unsigned longs */ 70130803Smarcel}; 71130803Smarcel 72130803Smarcel/* 73130803Smarcel * Define high and low longwords. 74130803Smarcel */ 75130803Smarcel#define H _QUAD_HIGHWORD 76130803Smarcel#define L _QUAD_LOWWORD 77130803Smarcel 78130803Smarcel/* 79130803Smarcel * Total number of bits in a quad_t and in the pieces that make it up. 80130803Smarcel * These are used for shifting, and also below for halfword extraction 81130803Smarcel * and assembly. 82130803Smarcel */ 83130803Smarcel#define QUAD_BITS (sizeof(quad_t) * CHAR_BIT) 84130803Smarcel#define LONG_BITS (sizeof(long) * CHAR_BIT) 85130803Smarcel#define HALF_BITS (sizeof(long) * CHAR_BIT / 2) 86130803Smarcel 87130803Smarcel/* 88130803Smarcel * Extract high and low shortwords from longword, and move low shortword of 89130803Smarcel * longword to upper half of long, i.e., produce the upper longword of 90130803Smarcel * ((quad_t)(x) << (number_of_bits_in_long/2)). (`x' must actually be u_long.) 91130803Smarcel * 92130803Smarcel * These are used in the multiply code, to split a longword into upper 93130803Smarcel * and lower halves, and to reassemble a product as a quad_t, shifted left 94130803Smarcel * (sizeof(long)*CHAR_BIT/2). 95130803Smarcel */ 96130803Smarcel#define HHALF(x) ((x) >> HALF_BITS) 97130803Smarcel#define LHALF(x) ((x) & ((1 << HALF_BITS) - 1)) 98130803Smarcel#define LHUP(x) ((x) << HALF_BITS) 99130803Smarcel 100130803Smarcelquad_t __divdi3 __P((quad_t a, quad_t b)); 101130803Smarcelquad_t __moddi3 __P((quad_t a, quad_t b)); 102130803Smarcelu_quad_t __qdivrem __P((u_quad_t u, u_quad_t v, u_quad_t *rem)); 103130803Smarcelu_quad_t __udivdi3 __P((u_quad_t a, u_quad_t b)); 104130803Smarcelu_quad_t __umoddi3 __P((u_quad_t a, u_quad_t b)); 105130803Smarcel 106130803Smarcel/* 107130803Smarcel * XXX 108130803Smarcel * Compensate for gcc 1 vs gcc 2. Gcc 1 defines ?sh?di3's second argument 109130803Smarcel * as u_quad_t, while gcc 2 correctly uses int. Unfortunately, we still use 110130803Smarcel * both compilers. 111130803Smarcel */ 112130803Smarcel#if __GNUC__ >= 2 113130803Smarceltypedef unsigned int qshift_t; 114130803Smarcel#else 115130803Smarceltypedef u_quad_t qshift_t; 116130803Smarcel#endif 117130803Smarcel