-//===-- Support/MathExtras.h - Useful math functions -------------*- C++ -*--=//
+//===-- llvm/Support/MathExtras.h - Useful math functions -------*- C++ -*-===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
//
// This file contains some functions that are useful for math stuff.
//
//===----------------------------------------------------------------------===//
-#ifndef SUPPORT_MATH_EXTRAS_H
-#define SUPPORT_MATH_EXTRAS_H
+#ifndef LLVM_SUPPORT_MATHEXTRAS_H
+#define LLVM_SUPPORT_MATHEXTRAS_H
+
+#include "llvm/Support/DataTypes.h"
+
+namespace llvm {
+
+// NOTE: The following support functions use the _32/_64 extensions instead of
+// type overloading so that signed and unsigned integers can be used without
+// ambiguity.
+
+/// Hi_32 - This function returns the high 32 bits of a 64 bit value.
+inline uint32_t Hi_32(uint64_t Value) {
+ return static_cast<uint32_t>(Value >> 32);
+}
+
+/// Lo_32 - This function returns the low 32 bits of a 64 bit value.
+inline uint32_t Lo_32(uint64_t Value) {
+ return static_cast<uint32_t>(Value);
+}
+
+/// is?Type - these functions produce optimal testing for integer data types.
+inline bool isInt8 (int64_t Value) {
+ return static_cast<int8_t>(Value) == Value;
+}
+inline bool isUInt8 (int64_t Value) {
+ return static_cast<uint8_t>(Value) == Value;
+}
+inline bool isInt16 (int64_t Value) {
+ return static_cast<int16_t>(Value) == Value;
+}
+inline bool isUInt16(int64_t Value) {
+ return static_cast<uint16_t>(Value) == Value;
+}
+inline bool isInt32 (int64_t Value) {
+ return static_cast<int32_t>(Value) == Value;
+}
+inline bool isUInt32(int64_t Value) {
+ return static_cast<uint32_t>(Value) == Value;
+}
+
+/// isMask_32 - This function returns true if the argument is a sequence of ones
+/// starting at the least significant bit with the remainder zero (32 bit
+/// version). Ex. isMask_32(0x0000FFFFU) == true.
+inline bool isMask_32(uint32_t Value) {
+ return Value && ((Value + 1) & Value) == 0;
+}
+
+/// isMask_64 - This function returns true if the argument is a sequence of ones
+/// starting at the least significant bit with the remainder zero (64 bit
+/// version).
+inline bool isMask_64(uint64_t Value) {
+ return Value && ((Value + 1) & Value) == 0;
+}
+
+/// isShiftedMask_32 - This function returns true if the argument contains a
+/// sequence of ones with the remainder zero (32 bit version.)
+/// Ex. isShiftedMask_32(0x0000FF00U) == true.
+inline bool isShiftedMask_32(uint32_t Value) {
+ return isMask_32((Value - 1) | Value);
+}
+
+/// isShiftedMask_64 - This function returns true if the argument contains a
+/// sequence of ones with the remainder zero (64 bit version.)
+inline bool isShiftedMask_64(uint64_t Value) {
+ return isMask_64((Value - 1) | Value);
+}
+
+/// isPowerOf2_32 - This function returns true if the argument is a power of
+/// two > 0. Ex. isPowerOf2_32(0x00100000U) == true (32 bit edition.)
+inline bool isPowerOf2_32(uint32_t Value) {
+ return Value && !(Value & (Value - 1));
+}
+
+/// isPowerOf2_64 - This function returns true if the argument is a power of two
+/// > 0 (64 bit edition.)
+inline bool isPowerOf2_64(uint64_t Value) {
+ return Value && !(Value & (Value - int64_t(1L)));
+}
+
+/// ByteSwap_16 - This function returns a byte-swapped representation of the
+/// 16-bit argument, Value.
+inline uint16_t ByteSwap_16(uint16_t Value) {
+#if defined(_MSC_VER) && !defined(_DEBUG)
+ // The DLL version of the runtime lacks these functions (bug!?), but in a
+ // release build they're replaced with BSWAP instructions anyway.
+ return _byteswap_ushort(Value);
+#else
+ uint16_t Hi = Value << 8;
+ uint16_t Lo = Value >> 8;
+ return Hi | Lo;
+#endif
+}
-#include <Support/DataTypes.h>
+/// ByteSwap_32 - This function returns a byte-swapped representation of the
+/// 32-bit argument, Value.
+inline uint32_t ByteSwap_32(uint32_t Value) {
+#if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 3)
+ return __builtin_bswap32(Value);
+#elif defined(_MSC_VER) && !defined(_DEBUG)
+ return _byteswap_ulong(Value);
+#else
+ uint32_t Byte0 = Value & 0x000000FF;
+ uint32_t Byte1 = Value & 0x0000FF00;
+ uint32_t Byte2 = Value & 0x00FF0000;
+ uint32_t Byte3 = Value & 0xFF000000;
+ return (Byte0 << 24) | (Byte1 << 8) | (Byte2 >> 8) | (Byte3 >> 24);
+#endif
+}
-inline unsigned log2(uint64_t C) {
- unsigned getPow;
- for (getPow = 0; C > 1; ++getPow)
- C >>= 1;
- return getPow;
+/// ByteSwap_64 - This function returns a byte-swapped representation of the
+/// 64-bit argument, Value.
+inline uint64_t ByteSwap_64(uint64_t Value) {
+#if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 3)
+ return __builtin_bswap64(Value);
+#elif defined(_MSC_VER) && !defined(_DEBUG)
+ return _byteswap_uint64(Value);
+#else
+ uint64_t Hi = ByteSwap_32(uint32_t(Value));
+ uint32_t Lo = ByteSwap_32(uint32_t(Value >> 32));
+ return (Hi << 32) | Lo;
+#endif
}
-inline bool isPowerOf2(int64_t C, unsigned &getPow) {
- if (C < 0) C = -C;
- if (C > 0 && C == (C & ~(C - 1))) {
- getPow = log2((uint64_t)C);
- return true;
+/// CountLeadingZeros_32 - this function performs the platform optimal form of
+/// counting the number of zeros from the most significant bit to the first one
+/// bit. Ex. CountLeadingZeros_32(0x00F000FF) == 8.
+/// Returns 32 if the word is zero.
+inline unsigned CountLeadingZeros_32(uint32_t Value) {
+ unsigned Count; // result
+#if __GNUC__ >= 4
+ // PowerPC is defined for __builtin_clz(0)
+#if !defined(__ppc__) && !defined(__ppc64__)
+ if (!Value) return 32;
+#endif
+ Count = __builtin_clz(Value);
+#else
+ if (!Value) return 32;
+ Count = 0;
+ // bisecton method for count leading zeros
+ for (unsigned Shift = 32 >> 1; Shift; Shift >>= 1) {
+ uint32_t Tmp = Value >> Shift;
+ if (Tmp) {
+ Value = Tmp;
+ } else {
+ Count |= Shift;
+ }
}
+#endif
+ return Count;
+}
+
+/// CountLeadingOnes_32 - this function performs the operation of
+/// counting the number of ones from the most significant bit to the first zero
+/// bit. Ex. CountLeadingOnes_32(0xFF0FFF00) == 8.
+/// Returns 32 if the word is all ones.
+inline unsigned CountLeadingOnes_32(uint32_t Value) {
+ return CountLeadingZeros_32(~Value);
+}
+
+/// CountLeadingZeros_64 - This function performs the platform optimal form
+/// of counting the number of zeros from the most significant bit to the first
+/// one bit (64 bit edition.)
+/// Returns 64 if the word is zero.
+inline unsigned CountLeadingZeros_64(uint64_t Value) {
+ unsigned Count; // result
+#if __GNUC__ >= 4
+ // PowerPC is defined for __builtin_clzll(0)
+#if !defined(__ppc__) && !defined(__ppc64__)
+ if (!Value) return 64;
+#endif
+ Count = __builtin_clzll(Value);
+#else
+ if (sizeof(long) == sizeof(int64_t)) {
+ if (!Value) return 64;
+ Count = 0;
+ // bisecton method for count leading zeros
+ for (unsigned Shift = 64 >> 1; Shift; Shift >>= 1) {
+ uint64_t Tmp = Value >> Shift;
+ if (Tmp) {
+ Value = Tmp;
+ } else {
+ Count |= Shift;
+ }
+ }
+ } else {
+ // get hi portion
+ uint32_t Hi = Hi_32(Value);
+
+ // if some bits in hi portion
+ if (Hi) {
+ // leading zeros in hi portion plus all bits in lo portion
+ Count = CountLeadingZeros_32(Hi);
+ } else {
+ // get lo portion
+ uint32_t Lo = Lo_32(Value);
+ // same as 32 bit value
+ Count = CountLeadingZeros_32(Lo)+32;
+ }
+ }
+#endif
+ return Count;
+}
+
+/// CountLeadingOnes_64 - This function performs the operation
+/// of counting the number of ones from the most significant bit to the first
+/// zero bit (64 bit edition.)
+/// Returns 64 if the word is all ones.
+inline unsigned CountLeadingOnes_64(uint64_t Value) {
+ return CountLeadingZeros_64(~Value);
+}
+
+/// CountTrailingZeros_32 - this function performs the platform optimal form of
+/// counting the number of zeros from the least significant bit to the first one
+/// bit. Ex. CountTrailingZeros_32(0xFF00FF00) == 8.
+/// Returns 32 if the word is zero.
+inline unsigned CountTrailingZeros_32(uint32_t Value) {
+#if __GNUC__ >= 4
+ return Value ? __builtin_ctz(Value) : 32;
+#else
+ static const unsigned Mod37BitPosition[] = {
+ 32, 0, 1, 26, 2, 23, 27, 0, 3, 16, 24, 30, 28, 11, 0, 13,
+ 4, 7, 17, 0, 25, 22, 31, 15, 29, 10, 12, 6, 0, 21, 14, 9,
+ 5, 20, 8, 19, 18
+ };
+ return Mod37BitPosition[(-Value & Value) % 37];
+#endif
+}
+
+/// CountTrailingOnes_32 - this function performs the operation of
+/// counting the number of ones from the least significant bit to the first zero
+/// bit. Ex. CountTrailingOnes_32(0x00FF00FF) == 8.
+/// Returns 32 if the word is all ones.
+inline unsigned CountTrailingOnes_32(uint32_t Value) {
+ return CountTrailingZeros_32(~Value);
+}
+
+/// CountTrailingZeros_64 - This function performs the platform optimal form
+/// of counting the number of zeros from the least significant bit to the first
+/// one bit (64 bit edition.)
+/// Returns 64 if the word is zero.
+inline unsigned CountTrailingZeros_64(uint64_t Value) {
+#if __GNUC__ >= 4
+ return Value ? __builtin_ctzll(Value) : 64;
+#else
+ static const unsigned Mod67Position[] = {
+ 64, 0, 1, 39, 2, 15, 40, 23, 3, 12, 16, 59, 41, 19, 24, 54,
+ 4, 64, 13, 10, 17, 62, 60, 28, 42, 30, 20, 51, 25, 44, 55,
+ 47, 5, 32, 65, 38, 14, 22, 11, 58, 18, 53, 63, 9, 61, 27,
+ 29, 50, 43, 46, 31, 37, 21, 57, 52, 8, 26, 49, 45, 36, 56,
+ 7, 48, 35, 6, 34, 33, 0
+ };
+ return Mod67Position[(-Value & Value) % 67];
+#endif
+}
+
+/// CountTrailingOnes_64 - This function performs the operation
+/// of counting the number of ones from the least significant bit to the first
+/// zero bit (64 bit edition.)
+/// Returns 64 if the word is all ones.
+inline unsigned CountTrailingOnes_64(uint64_t Value) {
+ return CountTrailingZeros_64(~Value);
+}
+
+/// CountPopulation_32 - this function counts the number of set bits in a value.
+/// Ex. CountPopulation(0xF000F000) = 8
+/// Returns 0 if the word is zero.
+inline unsigned CountPopulation_32(uint32_t Value) {
+#if __GNUC__ >= 4
+ return __builtin_popcount(Value);
+#else
+ uint32_t v = Value - ((Value >> 1) & 0x55555555);
+ v = (v & 0x33333333) + ((v >> 2) & 0x33333333);
+ return ((v + (v >> 4) & 0xF0F0F0F) * 0x1010101) >> 24;
+#endif
+}
+
+/// CountPopulation_64 - this function counts the number of set bits in a value,
+/// (64 bit edition.)
+inline unsigned CountPopulation_64(uint64_t Value) {
+#if __GNUC__ >= 4
+ return __builtin_popcountll(Value);
+#else
+ uint64_t v = Value - ((Value >> 1) & 0x5555555555555555ULL);
+ v = (v & 0x3333333333333333ULL) + ((v >> 2) & 0x3333333333333333ULL);
+ v = (v + (v >> 4)) & 0x0F0F0F0F0F0F0F0FULL;
+ return unsigned((uint64_t)(v * 0x0101010101010101ULL) >> 56);
+#endif
+}
+
+/// Log2_32 - This function returns the floor log base 2 of the specified value,
+/// -1 if the value is zero. (32 bit edition.)
+/// Ex. Log2_32(32) == 5, Log2_32(1) == 0, Log2_32(0) == -1, Log2_32(6) == 2
+inline unsigned Log2_32(uint32_t Value) {
+ return 31 - CountLeadingZeros_32(Value);
+}
+
+/// Log2_64 - This function returns the floor log base 2 of the specified value,
+/// -1 if the value is zero. (64 bit edition.)
+inline unsigned Log2_64(uint64_t Value) {
+ return 63 - CountLeadingZeros_64(Value);
+}
+
+/// Log2_32_Ceil - This function returns the ceil log base 2 of the specified
+/// value, 32 if the value is zero. (32 bit edition).
+/// Ex. Log2_32_Ceil(32) == 5, Log2_32_Ceil(1) == 0, Log2_32_Ceil(6) == 3
+inline unsigned Log2_32_Ceil(uint32_t Value) {
+ return 32-CountLeadingZeros_32(Value-1);
+}
+
+/// Log2_64 - This function returns the ceil log base 2 of the specified value,
+/// 64 if the value is zero. (64 bit edition.)
+inline unsigned Log2_64_Ceil(uint64_t Value) {
+ return 64-CountLeadingZeros_64(Value-1);
+}
+
+/// GreatestCommonDivisor64 - Return the greatest common divisor of the two
+/// values using Euclid's algorithm.
+inline uint64_t GreatestCommonDivisor64(uint64_t A, uint64_t B) {
+ while (B) {
+ uint64_t T = B;
+ B = A % B;
+ A = T;
+ }
+ return A;
+}
+
+/// BitsToDouble - This function takes a 64-bit integer and returns the bit
+/// equivalent double.
+inline double BitsToDouble(uint64_t Bits) {
+ union {
+ uint64_t L;
+ double D;
+ } T;
+ T.L = Bits;
+ return T.D;
+}
+
+/// BitsToFloat - This function takes a 32-bit integer and returns the bit
+/// equivalent float.
+inline float BitsToFloat(uint32_t Bits) {
+ union {
+ uint32_t I;
+ float F;
+ } T;
+ T.I = Bits;
+ return T.F;
+}
+
+/// DoubleToBits - This function takes a double and returns the bit
+/// equivalent 64-bit integer.
+inline uint64_t DoubleToBits(double Double) {
+ union {
+ uint64_t L;
+ double D;
+ } T;
+ T.D = Double;
+ return T.L;
+}
+
+/// FloatToBits - This function takes a float and returns the bit
+/// equivalent 32-bit integer.
+inline uint32_t FloatToBits(float Float) {
+ union {
+ uint32_t I;
+ float F;
+ } T;
+ T.F = Float;
+ return T.I;
+}
+
+/// Platform-independent wrappers for the C99 isnan() function.
+int IsNAN(float f);
+int IsNAN(double d);
+
+/// Platform-independent wrappers for the C99 isinf() function.
+int IsInf(float f);
+int IsInf(double d);
+
+/// MinAlign - A and B are either alignments or offsets. Return the minimum
+/// alignment that may be assumed after adding the two together.
+static inline uint64_t MinAlign(uint64_t A, uint64_t B) {
+ // The largest power of 2 that divides both A and B.
+ return (A | B) & -(A | B);
+}
- return false;
+/// NextPowerOf2 - Returns the next power of two (in 64-bits)
+/// that is strictly greater than A. Returns zero on overflow.
+static inline uint64_t NextPowerOf2(uint64_t A) {
+ A |= (A >> 1);
+ A |= (A >> 2);
+ A |= (A >> 4);
+ A |= (A >> 8);
+ A |= (A >> 16);
+ A |= (A >> 32);
+ return A + 1;
}
+
+} // End llvm namespace
#endif
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