intmath.hh revision 1642
15081Sgblack@eecs.umich.edu/* 25081Sgblack@eecs.umich.edu * Copyright (c) 2001, 2003 The Regents of The University of Michigan 35081Sgblack@eecs.umich.edu * All rights reserved. 45081Sgblack@eecs.umich.edu * 55081Sgblack@eecs.umich.edu * Redistribution and use in source and binary forms, with or without 65081Sgblack@eecs.umich.edu * modification, are permitted provided that the following conditions are 75081Sgblack@eecs.umich.edu * met: redistributions of source code must retain the above copyright 85081Sgblack@eecs.umich.edu * notice, this list of conditions and the following disclaimer; 95081Sgblack@eecs.umich.edu * redistributions in binary form must reproduce the above copyright 105081Sgblack@eecs.umich.edu * notice, this list of conditions and the following disclaimer in the 115081Sgblack@eecs.umich.edu * documentation and/or other materials provided with the distribution; 125081Sgblack@eecs.umich.edu * neither the name of the copyright holders nor the names of its 135081Sgblack@eecs.umich.edu * contributors may be used to endorse or promote products derived from 145081Sgblack@eecs.umich.edu * this software without specific prior written permission. 155081Sgblack@eecs.umich.edu * 165081Sgblack@eecs.umich.edu * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 175081Sgblack@eecs.umich.edu * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 185081Sgblack@eecs.umich.edu * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 195081Sgblack@eecs.umich.edu * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 205081Sgblack@eecs.umich.edu * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 215081Sgblack@eecs.umich.edu * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 225081Sgblack@eecs.umich.edu * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 235081Sgblack@eecs.umich.edu * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 245081Sgblack@eecs.umich.edu * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 255081Sgblack@eecs.umich.edu * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 265081Sgblack@eecs.umich.edu * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 275081Sgblack@eecs.umich.edu */ 285081Sgblack@eecs.umich.edu 295081Sgblack@eecs.umich.edu#ifndef __INTMATH_HH__ 305081Sgblack@eecs.umich.edu#define __INTMATH_HH__ 315081Sgblack@eecs.umich.edu 325081Sgblack@eecs.umich.edu#include <assert.h> 335081Sgblack@eecs.umich.edu 345081Sgblack@eecs.umich.edu#include "sim/host.hh" 355081Sgblack@eecs.umich.edu 365081Sgblack@eecs.umich.edu// Returns the prime number one less than n. 375081Sgblack@eecs.umich.eduint PrevPrime(int n); 385081Sgblack@eecs.umich.edu 395081Sgblack@eecs.umich.edu// Determine if a number is prime 405081Sgblack@eecs.umich.edutemplate <class T> 415081Sgblack@eecs.umich.eduinline bool 425081Sgblack@eecs.umich.eduIsPrime(T n) 435081Sgblack@eecs.umich.edu{ 445081Sgblack@eecs.umich.edu T i; 455081Sgblack@eecs.umich.edu 465081Sgblack@eecs.umich.edu if (n == 2 || n == 3) 475081Sgblack@eecs.umich.edu return true; 485081Sgblack@eecs.umich.edu 495081Sgblack@eecs.umich.edu // Don't try every odd number to prove if it is a prime. 505081Sgblack@eecs.umich.edu // Toggle between every 2nd and 4th number. 515081Sgblack@eecs.umich.edu // (This is because every 6th odd number is divisible by 3.) 525081Sgblack@eecs.umich.edu for (i = 5; i*i <= n; i += 6) { 535081Sgblack@eecs.umich.edu if (((n % i) == 0 ) || ((n % (i + 2)) == 0) ) { 545081Sgblack@eecs.umich.edu return false; 555081Sgblack@eecs.umich.edu } 565081Sgblack@eecs.umich.edu } 575081Sgblack@eecs.umich.edu 585081Sgblack@eecs.umich.edu return true; 595081Sgblack@eecs.umich.edu} 605081Sgblack@eecs.umich.edu 615081Sgblack@eecs.umich.edutemplate <class T> 625081Sgblack@eecs.umich.eduinline T 635081Sgblack@eecs.umich.eduLeastSigBit(T n) 645119Sgblack@eecs.umich.edu{ 655081Sgblack@eecs.umich.edu return n & ~(n - 1); 665081Sgblack@eecs.umich.edu} 675081Sgblack@eecs.umich.edu 685081Sgblack@eecs.umich.edutemplate <class T> 695081Sgblack@eecs.umich.eduinline bool 705081Sgblack@eecs.umich.eduIsPowerOf2(T n) 715081Sgblack@eecs.umich.edu{ 725119Sgblack@eecs.umich.edu return n != 0 && LeastSigBit(n) == n; 735081Sgblack@eecs.umich.edu} 745081Sgblack@eecs.umich.edu 755081Sgblack@eecs.umich.eduinline int 765081Sgblack@eecs.umich.eduFloorLog2(unsigned x) 776091Sgblack@eecs.umich.edu{ 786091Sgblack@eecs.umich.edu assert(x > 0); 796091Sgblack@eecs.umich.edu 806091Sgblack@eecs.umich.edu int y = 0; 816091Sgblack@eecs.umich.edu 826091Sgblack@eecs.umich.edu if (x & 0xffff0000) { y += 16; x >>= 16; } 836091Sgblack@eecs.umich.edu if (x & 0x0000ff00) { y += 8; x >>= 8; } 846091Sgblack@eecs.umich.edu if (x & 0x000000f0) { y += 4; x >>= 4; } 856091Sgblack@eecs.umich.edu if (x & 0x0000000c) { y += 2; x >>= 2; } 866091Sgblack@eecs.umich.edu if (x & 0x00000002) { y += 1; } 876091Sgblack@eecs.umich.edu 886091Sgblack@eecs.umich.edu return y; 896091Sgblack@eecs.umich.edu} 906091Sgblack@eecs.umich.edu 916091Sgblack@eecs.umich.eduinline int 925081Sgblack@eecs.umich.eduFloorLog2(unsigned long x) 935081Sgblack@eecs.umich.edu{ 945081Sgblack@eecs.umich.edu assert(x > 0); 955081Sgblack@eecs.umich.edu 965081Sgblack@eecs.umich.edu int y = 0; 975081Sgblack@eecs.umich.edu 985081Sgblack@eecs.umich.edu#if defined(__LP64__) 995119Sgblack@eecs.umich.edu if (x & ULL(0xffffffff00000000)) { y += 32; x >>= 32; } 1005081Sgblack@eecs.umich.edu#endif 1015081Sgblack@eecs.umich.edu if (x & 0xffff0000) { y += 16; x >>= 16; } 1025081Sgblack@eecs.umich.edu if (x & 0x0000ff00) { y += 8; x >>= 8; } 1035081Sgblack@eecs.umich.edu if (x & 0x000000f0) { y += 4; x >>= 4; } 1045081Sgblack@eecs.umich.edu if (x & 0x0000000c) { y += 2; x >>= 2; } 1055081Sgblack@eecs.umich.edu if (x & 0x00000002) { y += 1; } 1065081Sgblack@eecs.umich.edu 1075119Sgblack@eecs.umich.edu return y; 1085081Sgblack@eecs.umich.edu} 1095081Sgblack@eecs.umich.edu 1105081Sgblack@eecs.umich.eduinline int 1116092Sgblack@eecs.umich.eduFloorLog2(unsigned long long x) 1126092Sgblack@eecs.umich.edu{ 1136092Sgblack@eecs.umich.edu assert(x > 0); 1146092Sgblack@eecs.umich.edu 1156092Sgblack@eecs.umich.edu int y = 0; 1166092Sgblack@eecs.umich.edu 1176092Sgblack@eecs.umich.edu if (x & ULL(0xffffffff00000000)) { y += 32; x >>= 32; } 1186092Sgblack@eecs.umich.edu if (x & ULL(0x00000000ffff0000)) { y += 16; x >>= 16; } 1196092Sgblack@eecs.umich.edu if (x & ULL(0x000000000000ff00)) { y += 8; x >>= 8; } 1206092Sgblack@eecs.umich.edu if (x & ULL(0x00000000000000f0)) { y += 4; x >>= 4; } 1216092Sgblack@eecs.umich.edu if (x & ULL(0x000000000000000c)) { y += 2; x >>= 2; } 1226092Sgblack@eecs.umich.edu if (x & ULL(0x0000000000000002)) { y += 1; } 1236092Sgblack@eecs.umich.edu 1246092Sgblack@eecs.umich.edu return y; 1256092Sgblack@eecs.umich.edu} 1265081Sgblack@eecs.umich.edu 127inline int 128FloorLog2(int x) 129{ 130 assert(x > 0); 131 return FloorLog2((unsigned)x); 132} 133 134inline int 135FloorLog2(long x) 136{ 137 assert(x > 0); 138 return FloorLog2((unsigned long)x); 139} 140 141inline int 142FloorLog2(long long x) 143{ 144 assert(x > 0); 145 return FloorLog2((unsigned long long)x); 146} 147 148#if defined(__APPLE__) 149inline int 150FloorLog2(size_t x) 151{ 152 assert(x > 0); 153 assert(sizeof(size_t) == 4 || sizeof(size_t) == 8); 154 155 // It's my hope that this is optimized away? 156 if (sizeof(size_t) == 4) 157 return FloorLog2((uint32_t)x); 158 else if (sizeof(size_t) == 8) 159 return FloorLog2((uint64_t)x); 160 161} 162#endif 163 164template <class T> 165inline int 166CeilLog2(T n) 167{ 168 if (n == 1) 169 return 0; 170 171 return FloorLog2(n - (T)1) + 1; 172} 173 174template <class T> 175inline T 176FloorPow2(T n) 177{ 178 return (T)1 << FloorLog2(n); 179} 180 181template <class T> 182inline T 183CeilPow2(T n) 184{ 185 return (T)1 << CeilLog2(n); 186} 187 188template <class T> 189inline T 190DivCeil(T a, T b) 191{ 192 return (a + b - 1) / b; 193} 194 195template <class T> 196inline T 197RoundUp(T val, T align) 198{ 199 T mask = align - 1; 200 return (val + mask) & ~mask; 201} 202 203template <class T> 204inline T 205RoundDown(T val, T align) 206{ 207 T mask = align - 1; 208 return val & ~mask; 209} 210 211inline bool 212IsHex(char c) 213{ 214 return c >= '0' && c <= '9' || 215 c >= 'A' && c <= 'F' || 216 c >= 'a' && c <= 'f'; 217} 218 219inline bool 220IsOct(char c) 221{ 222 return c >= '0' && c <= '7'; 223} 224 225inline bool 226IsDec(char c) 227{ 228 return c >= '0' && c <= '9'; 229} 230 231inline int 232Hex2Int(char c) 233{ 234 if (c >= '0' && c <= '9') 235 return (c - '0'); 236 237 if (c >= 'A' && c <= 'F') 238 return (c - 'A') + 10; 239 240 if (c >= 'a' && c <= 'f') 241 return (c - 'a') + 10; 242 243 return 0; 244} 245 246#endif // __INTMATH_HH__ 247