MathExtras.h revision 0683c8cad920d241d44b126972d5cdd164dcc213
1551ccae044b0ff658fe629dd67edd5ffe75d10e8Reid Spencer//===-- llvm/Support/MathExtras.h - Useful math functions -------*- C++ -*-===// 263b3afa98460ce38a1c48d3c44ef6edfdaf37b77Misha Brukman// 3b2109ce97881269a610fa4afbcbca350e975174dJohn Criswell// The LLVM Compiler Infrastructure 4b2109ce97881269a610fa4afbcbca350e975174dJohn Criswell// 5b2109ce97881269a610fa4afbcbca350e975174dJohn Criswell// This file was developed by the LLVM research group and is distributed under 6b2109ce97881269a610fa4afbcbca350e975174dJohn Criswell// the University of Illinois Open Source License. See LICENSE.TXT for details. 763b3afa98460ce38a1c48d3c44ef6edfdaf37b77Misha Brukman// 8b2109ce97881269a610fa4afbcbca350e975174dJohn Criswell//===----------------------------------------------------------------------===// 954ea60c69e69b8e5a464a1d7688ceec5c68bacd5Chris Lattner// 1054ea60c69e69b8e5a464a1d7688ceec5c68bacd5Chris Lattner// This file contains some functions that are useful for math stuff. 1154ea60c69e69b8e5a464a1d7688ceec5c68bacd5Chris Lattner// 1254ea60c69e69b8e5a464a1d7688ceec5c68bacd5Chris Lattner//===----------------------------------------------------------------------===// 13cee8f9ae67104576b2028125b56e9ba4856a1d66Chris Lattner 14551ccae044b0ff658fe629dd67edd5ffe75d10e8Reid Spencer#ifndef LLVM_SUPPORT_MATHEXTRAS_H 15551ccae044b0ff658fe629dd67edd5ffe75d10e8Reid Spencer#define LLVM_SUPPORT_MATHEXTRAS_H 16cee8f9ae67104576b2028125b56e9ba4856a1d66Chris Lattner 17551ccae044b0ff658fe629dd67edd5ffe75d10e8Reid Spencer#include "llvm/Support/DataTypes.h" 18cee8f9ae67104576b2028125b56e9ba4856a1d66Chris Lattner 19d0fde30ce850b78371fd1386338350591f9ff494Brian Gaekenamespace llvm { 20d0fde30ce850b78371fd1386338350591f9ff494Brian Gaeke 2189bfcd34cbd2f4c6bb2cafff0a5c2bff147fae11Chris Lattner// NOTE: The following support functions use the _32/_64 extensions instead of 2289bfcd34cbd2f4c6bb2cafff0a5c2bff147fae11Chris Lattner// type overloading so that signed and unsigned integers can be used without 2389bfcd34cbd2f4c6bb2cafff0a5c2bff147fae11Chris Lattner// ambiguity. 2488c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattner 2588c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattner 2688c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattner// Hi_32 - This function returns the high 32 bits of a 64 bit value. 2788c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattnerinline unsigned Hi_32(uint64_t Value) { 2872a8e6f58cc7fd666f74a03c42cab616ddac7402Reid Spencer return static_cast<unsigned>(Value >> 32); 2988c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattner} 3088c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattner 3188c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattner// Lo_32 - This function returns the low 32 bits of a 64 bit value. 3288c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattnerinline unsigned Lo_32(uint64_t Value) { 3372a8e6f58cc7fd666f74a03c42cab616ddac7402Reid Spencer return static_cast<unsigned>(Value); 3488c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattner} 3588c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattner 3688c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattner// is?Type - these functions produce optimal testing for integer data types. 3754cb98578ac2eff4d5986eff7d2b18c66561d683Reid Spencerinline bool isInt8 (int Value) { 3854cb98578ac2eff4d5986eff7d2b18c66561d683Reid Spencer return static_cast<signed char>(Value) == Value; 3954cb98578ac2eff4d5986eff7d2b18c66561d683Reid Spencer} 4054cb98578ac2eff4d5986eff7d2b18c66561d683Reid Spencerinline bool isUInt8 (int Value) { 4154cb98578ac2eff4d5986eff7d2b18c66561d683Reid Spencer return static_cast<unsigned char>(Value) == Value; 4254cb98578ac2eff4d5986eff7d2b18c66561d683Reid Spencer} 4354cb98578ac2eff4d5986eff7d2b18c66561d683Reid Spencerinline bool isInt16 (int Value) { 4454cb98578ac2eff4d5986eff7d2b18c66561d683Reid Spencer return static_cast<signed short>(Value) == Value; 4554cb98578ac2eff4d5986eff7d2b18c66561d683Reid Spencer} 4654cb98578ac2eff4d5986eff7d2b18c66561d683Reid Spencerinline bool isUInt16(int Value) { 4754cb98578ac2eff4d5986eff7d2b18c66561d683Reid Spencer return static_cast<unsigned short>(Value) == Value; 4854cb98578ac2eff4d5986eff7d2b18c66561d683Reid Spencer} 4954cb98578ac2eff4d5986eff7d2b18c66561d683Reid Spencerinline bool isInt32 (int64_t Value) { 5054cb98578ac2eff4d5986eff7d2b18c66561d683Reid Spencer return static_cast<signed int>(Value) == Value; 5154cb98578ac2eff4d5986eff7d2b18c66561d683Reid Spencer} 5254cb98578ac2eff4d5986eff7d2b18c66561d683Reid Spencerinline bool isUInt32(int64_t Value) { 5354cb98578ac2eff4d5986eff7d2b18c66561d683Reid Spencer return static_cast<unsigned int>(Value) == Value; 5454cb98578ac2eff4d5986eff7d2b18c66561d683Reid Spencer} 5588c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattner 5689bfcd34cbd2f4c6bb2cafff0a5c2bff147fae11Chris Lattner// isMask_32 - This function returns true if the argument is a sequence of ones 5789bfcd34cbd2f4c6bb2cafff0a5c2bff147fae11Chris Lattner// starting at the least significant bit with the remainder zero (32 bit version.) 5888c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattner// Ex. isMask_32(0x0000FFFFU) == true. 5988c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattnerinline const bool isMask_32(unsigned Value) { 6088c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattner return Value && ((Value + 1) & Value) == 0; 6188c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattner} 6288c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattner 6389bfcd34cbd2f4c6bb2cafff0a5c2bff147fae11Chris Lattner// isMask_64 - This function returns true if the argument is a sequence of ones 6489bfcd34cbd2f4c6bb2cafff0a5c2bff147fae11Chris Lattner// starting at the least significant bit with the remainder zero (64 bit version.) 6588c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattnerinline const bool isMask_64(uint64_t Value) { 6688c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattner return Value && ((Value + 1) & Value) == 0; 6788c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattner} 6888c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattner 6989bfcd34cbd2f4c6bb2cafff0a5c2bff147fae11Chris Lattner// isShiftedMask_32 - This function returns true if the argument contains a 7089bfcd34cbd2f4c6bb2cafff0a5c2bff147fae11Chris Lattner// sequence of ones with the remainder zero (32 bit version.) 7188c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattner// Ex. isShiftedMask_32(0x0000FF00U) == true. 7288c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattnerinline const bool isShiftedMask_32(unsigned Value) { 7388c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattner return isMask_32((Value - 1) | Value); 7488c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattner} 7588c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattner 7689bfcd34cbd2f4c6bb2cafff0a5c2bff147fae11Chris Lattner// isShiftedMask_64 - This function returns true if the argument contains a 7789bfcd34cbd2f4c6bb2cafff0a5c2bff147fae11Chris Lattner// sequence of ones with the remainder zero (64 bit version.) 7888c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattnerinline const bool isShiftedMask_64(uint64_t Value) { 7988c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattner return isMask_64((Value - 1) | Value); 8088c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattner} 8188c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattner 8289bfcd34cbd2f4c6bb2cafff0a5c2bff147fae11Chris Lattner// isPowerOf2_32 - This function returns true if the argument is a power of 8389bfcd34cbd2f4c6bb2cafff0a5c2bff147fae11Chris Lattner// two > 0. Ex. isPowerOf2_32(0x00100000U) == true (32 bit edition.) 8488c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattnerinline bool isPowerOf2_32(unsigned Value) { 8588c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattner return Value && !(Value & (Value - 1)); 8688c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattner} 8788c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattner 88e6ec587059eb142467cc8a5915946a3b308cb9b7Chris Lattner// isPowerOf2_64 - This function returns true if the argument is a power of two 89e6ec587059eb142467cc8a5915946a3b308cb9b7Chris Lattner// > 0 (64 bit edition.) 9088c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattnerinline bool isPowerOf2_64(uint64_t Value) { 9119b7e0e0cabfa6dfc559c64e3d6ed053832c4047Reid Spencer return Value && !(Value & (Value - int64_t(1L))); 9288c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattner} 9388c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattner 946fb3bd6a658940287789198d3207b0da04c0a4e6Nate Begeman// ByteSwap_16 - This function returns a byte-swapped representation of the 956fb3bd6a658940287789198d3207b0da04c0a4e6Nate Begeman// 16-bit argument, Value. 966fb3bd6a658940287789198d3207b0da04c0a4e6Nate Begemaninline unsigned short ByteSwap_16(unsigned short Value) { 976fb3bd6a658940287789198d3207b0da04c0a4e6Nate Begeman unsigned short Hi = Value << 8; 986fb3bd6a658940287789198d3207b0da04c0a4e6Nate Begeman unsigned short Lo = Value >> 8; 996fb3bd6a658940287789198d3207b0da04c0a4e6Nate Begeman return Hi | Lo; 1006fb3bd6a658940287789198d3207b0da04c0a4e6Nate Begeman} 1016fb3bd6a658940287789198d3207b0da04c0a4e6Nate Begeman 1026fb3bd6a658940287789198d3207b0da04c0a4e6Nate Begeman// ByteSwap_32 - This function returns a byte-swapped representation of the 1036fb3bd6a658940287789198d3207b0da04c0a4e6Nate Begeman// 32-bit argument, Value. 1046fb3bd6a658940287789198d3207b0da04c0a4e6Nate Begemaninline unsigned ByteSwap_32(unsigned Value) { 1056fb3bd6a658940287789198d3207b0da04c0a4e6Nate Begeman unsigned Byte0 = Value & 0x000000FF; 1066fb3bd6a658940287789198d3207b0da04c0a4e6Nate Begeman unsigned Byte1 = Value & 0x0000FF00; 1076fb3bd6a658940287789198d3207b0da04c0a4e6Nate Begeman unsigned Byte2 = Value & 0x00FF0000; 1086fb3bd6a658940287789198d3207b0da04c0a4e6Nate Begeman unsigned Byte3 = Value & 0xFF000000; 1096fb3bd6a658940287789198d3207b0da04c0a4e6Nate Begeman return (Byte0 << 24) | (Byte1 << 8) | (Byte2 >> 8) | (Byte3 >> 24); 1106fb3bd6a658940287789198d3207b0da04c0a4e6Nate Begeman} 1116fb3bd6a658940287789198d3207b0da04c0a4e6Nate Begeman 1126fb3bd6a658940287789198d3207b0da04c0a4e6Nate Begeman// ByteSwap_64 - This function returns a byte-swapped representation of the 1136fb3bd6a658940287789198d3207b0da04c0a4e6Nate Begeman// 64-bit argument, Value. 1146fb3bd6a658940287789198d3207b0da04c0a4e6Nate Begemaninline uint64_t ByteSwap_64(uint64_t Value) { 115b69c190c26da6d83391a4956ed2dfc0fe45b5bfaJeff Cohen uint64_t Hi = ByteSwap_32(unsigned(Value)); 116b69c190c26da6d83391a4956ed2dfc0fe45b5bfaJeff Cohen uint64_t Lo = ByteSwap_32(unsigned(Value >> 32)); 1176fb3bd6a658940287789198d3207b0da04c0a4e6Nate Begeman return (Hi << 32) | Lo; 1186fb3bd6a658940287789198d3207b0da04c0a4e6Nate Begeman} 1196fb3bd6a658940287789198d3207b0da04c0a4e6Nate Begeman 120e6ec587059eb142467cc8a5915946a3b308cb9b7Chris Lattner// CountLeadingZeros_32 - this function performs the platform optimal form of 121e6ec587059eb142467cc8a5915946a3b308cb9b7Chris Lattner// counting the number of zeros from the most significant bit to the first one 122e6ec587059eb142467cc8a5915946a3b308cb9b7Chris Lattner// bit. Ex. CountLeadingZeros_32(0x00F000FF) == 8. 123e6ec587059eb142467cc8a5915946a3b308cb9b7Chris Lattner// Returns 32 if the word is zero. 12488c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattnerinline unsigned CountLeadingZeros_32(unsigned Value) { 12588c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattner unsigned Count; // result 126e6ec587059eb142467cc8a5915946a3b308cb9b7Chris Lattner#if __GNUC__ >= 4 127e6ec587059eb142467cc8a5915946a3b308cb9b7Chris Lattner // PowerPC is defined for __builtin_clz(0) 128e6ec587059eb142467cc8a5915946a3b308cb9b7Chris Lattner#if !defined(__ppc__) && !defined(__ppc64__) 129e6ec587059eb142467cc8a5915946a3b308cb9b7Chris Lattner if (!Value) return 32; 130e6ec587059eb142467cc8a5915946a3b308cb9b7Chris Lattner#endif 131e6ec587059eb142467cc8a5915946a3b308cb9b7Chris Lattner Count = __builtin_clz(Value); 132e6ec587059eb142467cc8a5915946a3b308cb9b7Chris Lattner#else 133e6ec587059eb142467cc8a5915946a3b308cb9b7Chris Lattner if (!Value) return 32; 134e6ec587059eb142467cc8a5915946a3b308cb9b7Chris Lattner Count = 0; 135e6ec587059eb142467cc8a5915946a3b308cb9b7Chris Lattner // bisecton method for count leading zeros 136e6ec587059eb142467cc8a5915946a3b308cb9b7Chris Lattner for (unsigned Shift = 32 >> 1; Shift; Shift >>= 1) { 137e6ec587059eb142467cc8a5915946a3b308cb9b7Chris Lattner unsigned Tmp = Value >> Shift; 138e6ec587059eb142467cc8a5915946a3b308cb9b7Chris Lattner if (Tmp) { 139e6ec587059eb142467cc8a5915946a3b308cb9b7Chris Lattner Value = Tmp; 140e6ec587059eb142467cc8a5915946a3b308cb9b7Chris Lattner } else { 141e6ec587059eb142467cc8a5915946a3b308cb9b7Chris Lattner Count |= Shift; 14288c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattner } 143e6ec587059eb142467cc8a5915946a3b308cb9b7Chris Lattner } 144e6ec587059eb142467cc8a5915946a3b308cb9b7Chris Lattner#endif 14588c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattner return Count; 14688c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattner} 147bb92f6fbf2c36b3530f33eb2e8d1842764ec9fddBrian Gaeke 14888c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattner// CountLeadingZeros_64 - This function performs the platform optimal form 14989bfcd34cbd2f4c6bb2cafff0a5c2bff147fae11Chris Lattner// of counting the number of zeros from the most significant bit to the first 15089bfcd34cbd2f4c6bb2cafff0a5c2bff147fae11Chris Lattner// one bit (64 bit edition.) 15188c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattner// Returns 64 if the word is zero. 15288c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattnerinline unsigned CountLeadingZeros_64(uint64_t Value) { 15388c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattner unsigned Count; // result 154e6ec587059eb142467cc8a5915946a3b308cb9b7Chris Lattner#if __GNUC__ >= 4 155e6ec587059eb142467cc8a5915946a3b308cb9b7Chris Lattner // PowerPC is defined for __builtin_clzll(0) 15689bfcd34cbd2f4c6bb2cafff0a5c2bff147fae11Chris Lattner#if !defined(__ppc__) && !defined(__ppc64__) 157e6ec587059eb142467cc8a5915946a3b308cb9b7Chris Lattner if (!Value) return 64; 158e6ec587059eb142467cc8a5915946a3b308cb9b7Chris Lattner#endif 159e6ec587059eb142467cc8a5915946a3b308cb9b7Chris Lattner Count = __builtin_clzll(Value); 160e6ec587059eb142467cc8a5915946a3b308cb9b7Chris Lattner#else 1613b65576527b7e0098a401289f9245eb5266fda31Chris Lattner if (sizeof(long) == sizeof(int64_t)) { 16288c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattner if (!Value) return 64; 16388c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattner Count = 0; 16488c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattner // bisecton method for count leading zeros 16588c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattner for (uint64_t Shift = 64 >> 1; Shift; Shift >>= 1) { 16688c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattner uint64_t Tmp = Value >> Shift; 16788c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattner if (Tmp) { 16888c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattner Value = Tmp; 169e6ec587059eb142467cc8a5915946a3b308cb9b7Chris Lattner } else { 170e6ec587059eb142467cc8a5915946a3b308cb9b7Chris Lattner Count |= Shift; 17188c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattner } 1723b65576527b7e0098a401289f9245eb5266fda31Chris Lattner } 1733b65576527b7e0098a401289f9245eb5266fda31Chris Lattner } else { 17488c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattner // get hi portion 17588c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattner unsigned Hi = Hi_32(Value); 176cee8f9ae67104576b2028125b56e9ba4856a1d66Chris Lattner 17788c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattner // if some bits in hi portion 17888c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattner if (Hi) { 17988c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattner // leading zeros in hi portion plus all bits in lo portion 180865dc8f64f50b72dbc8acb7851e606357f9d81f1Chris Lattner Count = CountLeadingZeros_32(Hi); 18188c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattner } else { 18288c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattner // get lo portion 18388c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattner unsigned Lo = Lo_32(Value); 18488c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattner // same as 32 bit value 185865dc8f64f50b72dbc8acb7851e606357f9d81f1Chris Lattner Count = CountLeadingZeros_32(Lo)+32; 18688c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattner } 1873b65576527b7e0098a401289f9245eb5266fda31Chris Lattner } 1883b65576527b7e0098a401289f9245eb5266fda31Chris Lattner#endif 18988c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattner return Count; 190e265504e82310266271fa2329b6ef8115bbe8244Chris Lattner} 191e265504e82310266271fa2329b6ef8115bbe8244Chris Lattner 19216d6ea526482e733fe3bc63929e94c9e88b6708dNate Begeman// CountTrailingZeros_32 - this function performs the platform optimal form of 19316d6ea526482e733fe3bc63929e94c9e88b6708dNate Begeman// counting the number of zeros from the least significant bit to the first one 19416d6ea526482e733fe3bc63929e94c9e88b6708dNate Begeman// bit. Ex. CountTrailingZeros_32(0xFF00FF00) == 8. 19516d6ea526482e733fe3bc63929e94c9e88b6708dNate Begeman// Returns 32 if the word is zero. 19616d6ea526482e733fe3bc63929e94c9e88b6708dNate Begemaninline unsigned CountTrailingZeros_32(unsigned Value) { 19716d6ea526482e733fe3bc63929e94c9e88b6708dNate Begeman return 32 - CountLeadingZeros_32(~Value & (Value - 1)); 19816d6ea526482e733fe3bc63929e94c9e88b6708dNate Begeman} 19916d6ea526482e733fe3bc63929e94c9e88b6708dNate Begeman 20016d6ea526482e733fe3bc63929e94c9e88b6708dNate Begeman// CountTrailingZeros_64 - This function performs the platform optimal form 20116d6ea526482e733fe3bc63929e94c9e88b6708dNate Begeman// of counting the number of zeros from the least significant bit to the first 20216d6ea526482e733fe3bc63929e94c9e88b6708dNate Begeman// one bit (64 bit edition.) 20316d6ea526482e733fe3bc63929e94c9e88b6708dNate Begeman// Returns 64 if the word is zero. 20416d6ea526482e733fe3bc63929e94c9e88b6708dNate Begemaninline unsigned CountTrailingZeros_64(uint64_t Value) { 20516d6ea526482e733fe3bc63929e94c9e88b6708dNate Begeman return 64 - CountLeadingZeros_64(~Value & (Value - 1)); 20616d6ea526482e733fe3bc63929e94c9e88b6708dNate Begeman} 20716d6ea526482e733fe3bc63929e94c9e88b6708dNate Begeman 20816d6ea526482e733fe3bc63929e94c9e88b6708dNate Begeman// CountPopulation_32 - this function counts the number of set bits in a value. 20916d6ea526482e733fe3bc63929e94c9e88b6708dNate Begeman// Ex. CountPopulation(0xF000F000) = 8 21016d6ea526482e733fe3bc63929e94c9e88b6708dNate Begeman// Returns 0 if the word is zero. 21116d6ea526482e733fe3bc63929e94c9e88b6708dNate Begemaninline unsigned CountPopulation_32(unsigned Value) { 21216d6ea526482e733fe3bc63929e94c9e88b6708dNate Begeman unsigned x, t; 21316d6ea526482e733fe3bc63929e94c9e88b6708dNate Begeman x = Value - ((Value >> 1) & 0x55555555); 21416d6ea526482e733fe3bc63929e94c9e88b6708dNate Begeman t = ((x >> 2) & 0x33333333); 21516d6ea526482e733fe3bc63929e94c9e88b6708dNate Begeman x = (x & 0x33333333) + t; 21616d6ea526482e733fe3bc63929e94c9e88b6708dNate Begeman x = (x + (x >> 4)) & 0x0F0F0F0F; 21716d6ea526482e733fe3bc63929e94c9e88b6708dNate Begeman x = x + (x << 8); 21816d6ea526482e733fe3bc63929e94c9e88b6708dNate Begeman x = x + (x << 16); 21916d6ea526482e733fe3bc63929e94c9e88b6708dNate Begeman return x >> 24; 22016d6ea526482e733fe3bc63929e94c9e88b6708dNate Begeman} 22116d6ea526482e733fe3bc63929e94c9e88b6708dNate Begeman 22216d6ea526482e733fe3bc63929e94c9e88b6708dNate Begeman// CountPopulation_64 - this function counts the number of set bits in a value, 22316d6ea526482e733fe3bc63929e94c9e88b6708dNate Begeman// (64 bit edition.) 22416d6ea526482e733fe3bc63929e94c9e88b6708dNate Begemaninline unsigned CountPopulation_64(uint64_t Value) { 225cadee65f5411a09f6a75157febaac668fc1bd56eJeff Cohen return CountPopulation_32(unsigned(Value >> 32)) + 226cadee65f5411a09f6a75157febaac668fc1bd56eJeff Cohen CountPopulation_32(unsigned(Value)); 22716d6ea526482e733fe3bc63929e94c9e88b6708dNate Begeman} 22816d6ea526482e733fe3bc63929e94c9e88b6708dNate Begeman 22989bfcd34cbd2f4c6bb2cafff0a5c2bff147fae11Chris Lattner// Log2_32 - This function returns the floor log base 2 of the specified value, 23089bfcd34cbd2f4c6bb2cafff0a5c2bff147fae11Chris Lattner// -1 if the value is zero. (32 bit edition.) 2310683c8cad920d241d44b126972d5cdd164dcc213Chris Lattner// Ex. Log2_32(32) == 5, Log2_32(1) == 0, Log2_32(0) == -1, Log2_32(6) == 2 23288c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattnerinline unsigned Log2_32(unsigned Value) { 23388c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattner return 31 - CountLeadingZeros_32(Value); 23416d6ea526482e733fe3bc63929e94c9e88b6708dNate Begeman} 23554ea60c69e69b8e5a464a1d7688ceec5c68bacd5Chris Lattner 23689bfcd34cbd2f4c6bb2cafff0a5c2bff147fae11Chris Lattner// Log2_64 - This function returns the floor log base 2 of the specified value, 23789bfcd34cbd2f4c6bb2cafff0a5c2bff147fae11Chris Lattner// -1 if the value is zero. (64 bit edition.) 2382be12faabb3ce2d2d3979c73ac65d466fdea5ec5Chris Lattnerinline unsigned Log2_64(uint64_t Value) { 23988c606eb0cc5415ed367c24e073f7bb478501d34Chris Lattner return 63 - CountLeadingZeros_64(Value); 240cee8f9ae67104576b2028125b56e9ba4856a1d66Chris Lattner} 241cee8f9ae67104576b2028125b56e9ba4856a1d66Chris Lattner 2420683c8cad920d241d44b126972d5cdd164dcc213Chris Lattner// Log2_32_Ceil - This function returns the ceil log base 2 of the specified 2430683c8cad920d241d44b126972d5cdd164dcc213Chris Lattner// value, 32 if the value is zero. (32 bit edition). 2440683c8cad920d241d44b126972d5cdd164dcc213Chris Lattner// Ex. Log2_32_Ceil(32) == 5, Log2_32_Ceil(1) == 0, Log2_32_Ceil(6) == 3 2450683c8cad920d241d44b126972d5cdd164dcc213Chris Lattnerinline unsigned Log2_32_Ceil(unsigned Value) { 2460683c8cad920d241d44b126972d5cdd164dcc213Chris Lattner return 32-CountLeadingZeros_32(Value-1); 2470683c8cad920d241d44b126972d5cdd164dcc213Chris Lattner} 2480683c8cad920d241d44b126972d5cdd164dcc213Chris Lattner 2490683c8cad920d241d44b126972d5cdd164dcc213Chris Lattner// Log2_64 - This function returns the ceil log base 2 of the specified value, 2500683c8cad920d241d44b126972d5cdd164dcc213Chris Lattner// 64 if the value is zero. (64 bit edition.) 2510683c8cad920d241d44b126972d5cdd164dcc213Chris Lattnerinline unsigned Log2_64_Ceil(uint64_t Value) { 2520683c8cad920d241d44b126972d5cdd164dcc213Chris Lattner return 64-CountLeadingZeros_64(Value-1); 2530683c8cad920d241d44b126972d5cdd164dcc213Chris Lattner} 2540683c8cad920d241d44b126972d5cdd164dcc213Chris Lattner 25559b8fcfa5f736dff4a08ebcac032935b6fd92f34Jim Laskey// BitsToDouble - This function takes a 64-bit integer and returns the bit 25659b8fcfa5f736dff4a08ebcac032935b6fd92f34Jim Laskey// equivalent double. 25759b8fcfa5f736dff4a08ebcac032935b6fd92f34Jim Laskeyinline double BitsToDouble(uint64_t Bits) { 25859b8fcfa5f736dff4a08ebcac032935b6fd92f34Jim Laskey union { 25959b8fcfa5f736dff4a08ebcac032935b6fd92f34Jim Laskey uint64_t L; 26059b8fcfa5f736dff4a08ebcac032935b6fd92f34Jim Laskey double D; 26159b8fcfa5f736dff4a08ebcac032935b6fd92f34Jim Laskey } T; 26259b8fcfa5f736dff4a08ebcac032935b6fd92f34Jim Laskey T.L = Bits; 26359b8fcfa5f736dff4a08ebcac032935b6fd92f34Jim Laskey return T.D; 26459b8fcfa5f736dff4a08ebcac032935b6fd92f34Jim Laskey} 26559b8fcfa5f736dff4a08ebcac032935b6fd92f34Jim Laskey 26659b8fcfa5f736dff4a08ebcac032935b6fd92f34Jim Laskey// BitsToFloat - This function takes a 32-bit integer and returns the bit 26759b8fcfa5f736dff4a08ebcac032935b6fd92f34Jim Laskey// equivalent float. 268104338913500d007996056ad092e195009883a84Jim Laskeyinline float BitsToFloat(uint32_t Bits) { 26959b8fcfa5f736dff4a08ebcac032935b6fd92f34Jim Laskey union { 270104338913500d007996056ad092e195009883a84Jim Laskey uint32_t I; 27159b8fcfa5f736dff4a08ebcac032935b6fd92f34Jim Laskey float F; 27259b8fcfa5f736dff4a08ebcac032935b6fd92f34Jim Laskey } T; 27359b8fcfa5f736dff4a08ebcac032935b6fd92f34Jim Laskey T.I = Bits; 27459b8fcfa5f736dff4a08ebcac032935b6fd92f34Jim Laskey return T.F; 27559b8fcfa5f736dff4a08ebcac032935b6fd92f34Jim Laskey} 27659b8fcfa5f736dff4a08ebcac032935b6fd92f34Jim Laskey 27759b8fcfa5f736dff4a08ebcac032935b6fd92f34Jim Laskey// DoubleToBits - This function takes a double and returns the bit 27859b8fcfa5f736dff4a08ebcac032935b6fd92f34Jim Laskey// equivalent 64-bit integer. 27959b8fcfa5f736dff4a08ebcac032935b6fd92f34Jim Laskeyinline uint64_t DoubleToBits(double Double) { 28059b8fcfa5f736dff4a08ebcac032935b6fd92f34Jim Laskey union { 28159b8fcfa5f736dff4a08ebcac032935b6fd92f34Jim Laskey uint64_t L; 28259b8fcfa5f736dff4a08ebcac032935b6fd92f34Jim Laskey double D; 28359b8fcfa5f736dff4a08ebcac032935b6fd92f34Jim Laskey } T; 28459b8fcfa5f736dff4a08ebcac032935b6fd92f34Jim Laskey T.D = Double; 28559b8fcfa5f736dff4a08ebcac032935b6fd92f34Jim Laskey return T.L; 28659b8fcfa5f736dff4a08ebcac032935b6fd92f34Jim Laskey} 28759b8fcfa5f736dff4a08ebcac032935b6fd92f34Jim Laskey 28859b8fcfa5f736dff4a08ebcac032935b6fd92f34Jim Laskey// FloatToBits - This function takes a float and returns the bit 28959b8fcfa5f736dff4a08ebcac032935b6fd92f34Jim Laskey// equivalent 32-bit integer. 290104338913500d007996056ad092e195009883a84Jim Laskeyinline uint32_t FloatToBits(float Float) { 29159b8fcfa5f736dff4a08ebcac032935b6fd92f34Jim Laskey union { 292104338913500d007996056ad092e195009883a84Jim Laskey uint32_t I; 29359b8fcfa5f736dff4a08ebcac032935b6fd92f34Jim Laskey float F; 29459b8fcfa5f736dff4a08ebcac032935b6fd92f34Jim Laskey } T; 29559b8fcfa5f736dff4a08ebcac032935b6fd92f34Jim Laskey T.F = Float; 29659b8fcfa5f736dff4a08ebcac032935b6fd92f34Jim Laskey return T.I; 29759b8fcfa5f736dff4a08ebcac032935b6fd92f34Jim Laskey} 29859b8fcfa5f736dff4a08ebcac032935b6fd92f34Jim Laskey 2997764f4b2e0e550dc23f3c536f236f9abf86879dcBrian Gaeke// Platform-independent wrappers for the C99 isnan() function. 3007764f4b2e0e550dc23f3c536f236f9abf86879dcBrian Gaekeint IsNAN (float f); 3017764f4b2e0e550dc23f3c536f236f9abf86879dcBrian Gaekeint IsNAN (double d); 3027764f4b2e0e550dc23f3c536f236f9abf86879dcBrian Gaeke 303a7d03b466a41e68e11480ae6ca275140fe4c4507Brian Gaeke// Platform-independent wrappers for the C99 isinf() function. 304a7d03b466a41e68e11480ae6ca275140fe4c4507Brian Gaekeint IsInf (float f); 305a7d03b466a41e68e11480ae6ca275140fe4c4507Brian Gaekeint IsInf (double d); 306a7d03b466a41e68e11480ae6ca275140fe4c4507Brian Gaeke 307d0fde30ce850b78371fd1386338350591f9ff494Brian Gaeke} // End llvm namespace 308d0fde30ce850b78371fd1386338350591f9ff494Brian Gaeke 30954ea60c69e69b8e5a464a1d7688ceec5c68bacd5Chris Lattner#endif 310