#ifndef _DEINT32_H
#define _DEINT32_H
/*-------------------------------------------------------------------------
* drawElements Base Portability Library
* -------------------------------------
*
* Copyright 2014 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
*//*!
* \file
* \brief 32-bit integer math.
*//*--------------------------------------------------------------------*/
#include "deDefs.h"
#if (DE_COMPILER == DE_COMPILER_MSC)
# include <intrin.h>
#endif
DE_BEGIN_EXTERN_C
enum
{
DE_RCP_FRAC_BITS = 30 /*!< Number of fractional bits in deRcp32() result. */
};
void deRcp32 (deUint32 a, deUint32* rcp, int* exp);
void deInt32_computeLUTs (void);
void deInt32_selfTest (void);
/*--------------------------------------------------------------------*//*!
* \brief Compute the absolute of an int.
* \param a Input value.
* \return Absolute of the input value.
*
* \note The input 0x80000000u (for which the abs value cannot be
* represented), is asserted and returns the value itself.
*//*--------------------------------------------------------------------*/
DE_INLINE int deAbs32 (int a)
{
DE_ASSERT((unsigned int) a != 0x80000000u);
return (a < 0) ? -a : a;
}
/*--------------------------------------------------------------------*//*!
* \brief Compute the signed minimum of two values.
* \param a First input value.
* \param b Second input value.
* \return The smallest of the two input values.
*//*--------------------------------------------------------------------*/
DE_INLINE int deMin32 (int a, int b)
{
return (a <= b) ? a : b;
}
/*--------------------------------------------------------------------*//*!
* \brief Compute the signed maximum of two values.
* \param a First input value.
* \param b Second input value.
* \return The largest of the two input values.
*//*--------------------------------------------------------------------*/
DE_INLINE int deMax32 (int a, int b)
{
return (a >= b) ? a : b;
}
/*--------------------------------------------------------------------*//*!
* \brief Compute the unsigned minimum of two values.
* \param a First input value.
* \param b Second input value.
* \return The smallest of the two input values.
*//*--------------------------------------------------------------------*/
DE_INLINE deUint32 deMinu32 (deUint32 a, deUint32 b)
{
return (a <= b) ? a : b;
}
/*--------------------------------------------------------------------*//*!
* \brief Compute the unsigned maximum of two values.
* \param a First input value.
* \param b Second input value.
* \return The largest of the two input values.
*//*--------------------------------------------------------------------*/
DE_INLINE deUint32 deMaxu32 (deUint32 a, deUint32 b)
{
return (a >= b) ? a : b;
}
/*--------------------------------------------------------------------*//*!
* \brief Check if a value is in the <b>inclusive<b> range [mn, mx].
* \param a Value to check for range.
* \param mn Range minimum value.
* \param mx Range maximum value.
* \return True if (a >= mn) and (a <= mx), false otherwise.
*
* \see deInBounds32()
*//*--------------------------------------------------------------------*/
DE_INLINE deBool deInRange32 (int a, int mn, int mx)
{
return (a >= mn) && (a <= mx);
}
/*--------------------------------------------------------------------*//*!
* \brief Check if a value is in the half-inclusive bounds [mn, mx[.
* \param a Value to check for range.
* \param mn Range minimum value.
* \param mx Range maximum value.
* \return True if (a >= mn) and (a < mx), false otherwise.
*
* \see deInRange32()
*//*--------------------------------------------------------------------*/
DE_INLINE deBool deInBounds32 (int a, int mn, int mx)
{
return (a >= mn) && (a < mx);
}
/*--------------------------------------------------------------------*//*!
* \brief Clamp a value into the range [mn, mx].
* \param a Value to clamp.
* \param mn Minimum value.
* \param mx Maximum value.
* \return The clamped value in [mn, mx] range.
*//*--------------------------------------------------------------------*/
DE_INLINE int deClamp32 (int a, int mn, int mx)
{
DE_ASSERT(mn <= mx);
if (a < mn) return mn;
if (a > mx) return mx;
return a;
}
/*--------------------------------------------------------------------*//*!
* \brief Get the sign of an integer.
* \param a Input value.
* \return +1 if a>0, 0 if a==0, -1 if a<0.
*//*--------------------------------------------------------------------*/
DE_INLINE int deSign32 (int a)
{
if (a > 0) return +1;
if (a < 0) return -1;
return 0;
}
/*--------------------------------------------------------------------*//*!
* \brief Extract the sign bit of a.
* \param a Input value.
* \return 0x80000000 if a<0, 0 otherwise.
*//*--------------------------------------------------------------------*/
DE_INLINE deInt32 deSignBit32 (deInt32 a)
{
return (deInt32)((deUint32)a & 0x80000000u);
}
/*--------------------------------------------------------------------*//*!
* \brief Integer rotate right.
* \param val Value to rotate.
* \param r Number of bits to rotate (in range [0, 32]).
* \return The rotated value.
*//*--------------------------------------------------------------------*/
DE_INLINE int deRor32 (int val, int r)
{
DE_ASSERT(r >= 0 && r <= 32);
if (r == 0 || r == 32)
return val;
else
return (int)(((deUint32)val >> r) | ((deUint32)val << (32-r)));
}
/*--------------------------------------------------------------------*//*!
* \brief Integer rotate left.
* \param val Value to rotate.
* \param r Number of bits to rotate (in range [0, 32]).
* \return The rotated value.
*//*--------------------------------------------------------------------*/
DE_INLINE int deRol32 (int val, int r)
{
DE_ASSERT(r >= 0 && r <= 32);
if (r == 0 || r == 32)
return val;
else
return (int)(((deUint32)val << r) | ((deUint32)val >> (32-r)));
}
/*--------------------------------------------------------------------*//*!
* \brief Check if a value is a power-of-two.
* \param a Input value.
* \return True if input is a power-of-two value, false otherwise.
*
* \note Also returns true for zero.
*//*--------------------------------------------------------------------*/
DE_INLINE deBool deIsPowerOfTwo32 (int a)
{
return ((a & (a - 1)) == 0);
}
/*--------------------------------------------------------------------*//*!
* \brief Check if a value is a power-of-two.
* \param a Input value.
* \return True if input is a power-of-two value, false otherwise.
*
* \note Also returns true for zero.
*//*--------------------------------------------------------------------*/
DE_INLINE deBool deIsPowerOfTwo64 (deUint64 a)
{
return ((a & (a - 1ull)) == 0);
}
/*--------------------------------------------------------------------*//*!
* \brief Check if a value is a power-of-two.
* \param a Input value.
* \return True if input is a power-of-two value, false otherwise.
*
* \note Also returns true for zero.
*//*--------------------------------------------------------------------*/
DE_INLINE deBool deIsPowerOfTwoSize (size_t a)
{
#if (DE_PTR_SIZE == 4)
return deIsPowerOfTwo32(a);
#elif (DE_PTR_SIZE == 8)
return deIsPowerOfTwo64(a);
#else
# error "Invalid DE_PTR_SIZE"
#endif
}
/*--------------------------------------------------------------------*//*!
* \brief Check if an integer is aligned to given power-of-two size.
* \param a Input value.
* \param align Alignment to check for.
* \return True if input is aligned, false otherwise.
*//*--------------------------------------------------------------------*/
DE_INLINE deBool deIsAligned32 (int a, int align)
{
DE_ASSERT(deIsPowerOfTwo32(align));
return ((a & (align-1)) == 0);
}
/*--------------------------------------------------------------------*//*!
* \brief Check if a pointer is aligned to given power-of-two size.
* \param ptr Input pointer.
* \param align Alignment to check for (power-of-two).
* \return True if input is aligned, false otherwise.
*//*--------------------------------------------------------------------*/
DE_INLINE deBool deIsAlignedPtr (const void* ptr, deUintptr align)
{
DE_ASSERT((align & (align-1)) == 0); /* power of two */
return (((deUintptr)ptr & (align-1)) == 0);
}
/*--------------------------------------------------------------------*//*!
* \brief Align an integer to given power-of-two size.
* \param val Input to align.
* \param align Alignment to check for (power-of-two).
* \return The aligned value (larger or equal to input).
*//*--------------------------------------------------------------------*/
DE_INLINE deInt32 deAlign32 (deInt32 val, deInt32 align)
{
DE_ASSERT(deIsPowerOfTwo32(align));
return (val + align - 1) & ~(align - 1);
}
/*--------------------------------------------------------------------*//*!
* \brief Align a pointer to given power-of-two size.
* \param ptr Input pointer to align.
* \param align Alignment to check for (power-of-two).
* \return The aligned pointer (larger or equal to input).
*//*--------------------------------------------------------------------*/
DE_INLINE void* deAlignPtr (void* ptr, deUintptr align)
{
deUintptr val = (deUintptr)ptr;
DE_ASSERT((align & (align-1)) == 0); /* power of two */
return (void*)((val + align - 1) & ~(align - 1));
}
/*--------------------------------------------------------------------*//*!
* \brief Align a size_t value to given power-of-two size.
* \param ptr Input value to align.
* \param align Alignment to check for (power-of-two).
* \return The aligned size (larger or equal to input).
*//*--------------------------------------------------------------------*/
DE_INLINE size_t deAlignSize (size_t val, size_t align)
{
DE_ASSERT(deIsPowerOfTwoSize(align));
return (val + align - 1) & ~(align - 1);
}
extern const deInt8 g_clzLUT[256];
/*--------------------------------------------------------------------*//*!
* \brief Compute number of leading zeros in an integer.
* \param a Input value.
* \return The number of leading zero bits in the input.
*//*--------------------------------------------------------------------*/
DE_INLINE int deClz32 (deUint32 a)
{
#if (DE_COMPILER == DE_COMPILER_MSC)
unsigned long i;
if (_BitScanReverse(&i, (unsigned long)a) == 0)
return 32;
else
return 31-i;
#elif (DE_COMPILER == DE_COMPILER_GCC) || (DE_COMPILER == DE_COMPILER_CLANG)
if (a == 0)
return 32;
else
return __builtin_clz((unsigned int)a);
#else
if ((a & 0xFF000000u) != 0)
return (int)g_clzLUT[a >> 24];
if ((a & 0x00FF0000u) != 0)
return 8 + (int)g_clzLUT[a >> 16];
if ((a & 0x0000FF00u) != 0)
return 16 + (int)g_clzLUT[a >> 8];
return 24 + (int)g_clzLUT[a];
#endif
}
extern const deInt8 g_ctzLUT[256];
/*--------------------------------------------------------------------*//*!
* \brief Compute number of trailing zeros in an integer.
* \param a Input value.
* \return The number of trailing zero bits in the input.
*//*--------------------------------------------------------------------*/
DE_INLINE int deCtz32 (deUint32 a)
{
#if (DE_COMPILER == DE_COMPILER_MSC)
unsigned long i;
if (_BitScanForward(&i, (unsigned long)a) == 0)
return 32;
else
return i;
#elif (DE_COMPILER == DE_COMPILER_GCC) || (DE_COMPILER == DE_COMPILER_CLANG)
if (a == 0)
return 32;
else
return __builtin_ctz((unsigned int)a);
#else
if ((a & 0x00FFFFFFu) == 0)
return (int)g_ctzLUT[a >> 24] + 24;
if ((a & 0x0000FFFFu) == 0)
return (int)g_ctzLUT[(a >> 16) & 0xffu] + 16;
if ((a & 0x000000FFu) == 0)
return (int)g_ctzLUT[(a >> 8) & 0xffu] + 8;
return (int)g_ctzLUT[a & 0xffu];
#endif
}
/*--------------------------------------------------------------------*//*!
* \brief Compute integer 'floor' of 'log2' for a positive integer.
* \param a Input value.
* \return floor(log2(a)).
*//*--------------------------------------------------------------------*/
DE_INLINE int deLog2Floor32 (deInt32 a)
{
DE_ASSERT(a > 0);
return 31 - deClz32((deUint32)a);
}
/*--------------------------------------------------------------------*//*!
* \brief Compute integer 'ceil' of 'log2' for a positive integer.
* \param a Input value.
* \return ceil(log2(a)).
*//*--------------------------------------------------------------------*/
DE_INLINE int deLog2Ceil32 (deInt32 a)
{
int log2floor = deLog2Floor32(a);
if (deIsPowerOfTwo32(a))
return log2floor;
else
return log2floor+1;
}
/* \todo [2012-04-28 pyry] Badly named, deprecated variant of deLog2Ceil32(). Remove once code has been fixed. */
DE_INLINE deUint32 deLog2Clz(deInt32 a)
{
return (deUint32)deLog2Ceil32(a);
}
/*--------------------------------------------------------------------*//*!
* \brief Compute the bit population count of an integer.
* \param a Input value.
* \return The number of one bits in the input.
*//*--------------------------------------------------------------------*/
DE_INLINE int dePop32 (deUint32 a)
{
deUint32 mask0 = 0x55555555; /* 1-bit values. */
deUint32 mask1 = 0x33333333; /* 2-bit values. */
deUint32 mask2 = 0x0f0f0f0f; /* 4-bit values. */
deUint32 mask3 = 0x00ff00ff; /* 8-bit values. */
deUint32 mask4 = 0x0000ffff; /* 16-bit values. */
deUint32 t = (deUint32)a;
t = (t & mask0) + ((t>>1) & mask0);
t = (t & mask1) + ((t>>2) & mask1);
t = (t & mask2) + ((t>>4) & mask2);
t = (t & mask3) + ((t>>8) & mask3);
t = (t & mask4) + (t>>16);
return (int)t;
}
DE_INLINE int dePop64 (deUint64 a)
{
return dePop32((deUint32)(a & 0xffffffffull)) + dePop32((deUint32)(a >> 32));
}
/*--------------------------------------------------------------------*//*!
* \brief Reverse bytes in 32-bit integer (for example MSB -> LSB).
* \param a Input value.
* \return The input with bytes reversed
*//*--------------------------------------------------------------------*/
DE_INLINE deUint32 deReverseBytes32 (deUint32 v)
{
deUint32 b0 = v << 24;
deUint32 b1 = (v & 0x0000ff00) << 8;
deUint32 b2 = (v & 0x00ff0000) >> 8;
deUint32 b3 = v >> 24;
return b0|b1|b2|b3;
}
/*--------------------------------------------------------------------*//*!
* \brief Reverse bytes in 16-bit integer (for example MSB -> LSB).
* \param a Input value.
* \return The input with bytes reversed
*//*--------------------------------------------------------------------*/
DE_INLINE deUint16 deReverseBytes16 (deUint16 v)
{
return (deUint16)((v << 8) | (v >> 8));
}
DE_INLINE deInt32 deSafeMul32 (deInt32 a, deInt32 b)
{
deInt32 res = a * b;
DE_ASSERT((deInt64)res == ((deInt64)a * (deInt64)b));
return res;
}
DE_INLINE deInt32 deSafeAdd32 (deInt32 a, deInt32 b)
{
DE_ASSERT((deInt64)a + (deInt64)b == (deInt64)(a + b));
return (a + b);
}
DE_INLINE deInt32 deDivRoundUp32 (deInt32 a, deInt32 b)
{
return a/b + ((a%b) ? 1 : 0);
}
/* \todo [petri] Move to deInt64.h? */
DE_INLINE deInt32 deMulAsr32 (deInt32 a, deInt32 b, int shift)
{
return (deInt32)(((deInt64)a * (deInt64)b) >> shift);
}
DE_INLINE deInt32 deSafeMulAsr32 (deInt32 a, deInt32 b, int shift)
{
deInt64 res = ((deInt64)a * (deInt64)b) >> shift;
DE_ASSERT(res == (deInt64)(deInt32)res);
return (deInt32)res;
}
DE_INLINE deUint32 deSafeMuluAsr32 (deUint32 a, deUint32 b, int shift)
{
deUint64 res = ((deUint64)a * (deUint64)b) >> shift;
DE_ASSERT(res == (deUint64)(deUint32)res);
return (deUint32)res;
}
DE_INLINE deInt64 deMul32_32_64 (deInt32 a, deInt32 b)
{
return ((deInt64)a * (deInt64)b);
}
DE_INLINE deInt64 deAbs64 (deInt64 a)
{
DE_ASSERT((deUint64) a != 0x8000000000000000LL);
return (a >= 0) ? a : -a;
}
DE_INLINE int deClz64 (deUint64 a)
{
if ((a >> 32) != 0)
return deClz32((deUint32)(a >> 32));
return deClz32((deUint32)a) + 32;
}
/* Common hash & compare functions. */
DE_INLINE deUint32 deInt32Hash (deInt32 a)
{
/* From: http://www.concentric.net/~Ttwang/tech/inthash.htm */
deUint32 key = (deUint32)a;
key = (key ^ 61) ^ (key >> 16);
key = key + (key << 3);
key = key ^ (key >> 4);
key = key * 0x27d4eb2d; /* prime/odd constant */
key = key ^ (key >> 15);
return key;
}
DE_INLINE deUint32 deInt64Hash (deInt64 a)
{
/* From: http://www.concentric.net/~Ttwang/tech/inthash.htm */
deUint64 key = (deUint64)a;
key = (~key) + (key << 21); /* key = (key << 21) - key - 1; */
key = key ^ (key >> 24);
key = (key + (key << 3)) + (key << 8); /* key * 265 */
key = key ^ (key >> 14);
key = (key + (key << 2)) + (key << 4); /* key * 21 */
key = key ^ (key >> 28);
key = key + (key << 31);
return (deUint32)key;
}
DE_INLINE deUint32 deInt16Hash (deInt16 v) { return deInt32Hash(v); }
DE_INLINE deUint32 deUint16Hash (deUint16 v) { return deInt32Hash((deInt32)v); }
DE_INLINE deUint32 deUint32Hash (deUint32 v) { return deInt32Hash((deInt32)v); }
DE_INLINE deUint32 deUint64Hash (deUint64 v) { return deInt64Hash((deInt64)v); }
DE_INLINE deBool deInt16Equal (deInt16 a, deInt16 b) { return (a == b); }
DE_INLINE deBool deUint16Equal (deUint16 a, deUint16 b) { return (a == b); }
DE_INLINE deBool deInt32Equal (deInt32 a, deInt32 b) { return (a == b); }
DE_INLINE deBool deUint32Equal (deUint32 a, deUint32 b) { return (a == b); }
DE_INLINE deBool deInt64Equal (deInt64 a, deInt64 b) { return (a == b); }
DE_INLINE deBool deUint64Equal (deUint64 a, deUint64 b) { return (a == b); }
DE_INLINE deUint32 dePointerHash (const void* ptr)
{
deUintptr val = (deUintptr)ptr;
#if (DE_PTR_SIZE == 4)
return deInt32Hash((int)val);
#elif (DE_PTR_SIZE == 8)
return deInt64Hash((deInt64)val);
#else
# error Unsupported pointer size.
#endif
}
DE_INLINE deBool dePointerEqual (const void* a, const void* b)
{
return (a == b);
}
/**
* \brief Modulo that generates the same sign as divisor and rounds toward
* negative infinity -- assuming c99 %-operator.
*/
DE_INLINE deInt32 deInt32ModF (deInt32 n, deInt32 d)
{
deInt32 r = n%d;
if ((r > 0 && d < 0) || (r < 0 && d > 0)) r = r+d;
return r;
}
DE_INLINE deBool deInt64InInt32Range (deInt64 x)
{
return ((x >= (((deInt64)((deInt32)(-0x7FFFFFFF - 1))))) && (x <= ((1ll<<31)-1)));
}
DE_INLINE deUint32 deBitMask32 (int leastSignificantBitNdx, int numBits)
{
DE_ASSERT(deInRange32(leastSignificantBitNdx, 0, 32));
DE_ASSERT(deInRange32(numBits, 0, 32));
DE_ASSERT(deInRange32(leastSignificantBitNdx+numBits, 0, 32));
if (numBits < 32 && leastSignificantBitNdx < 32)
return ((1u<<numBits)-1u) << (deUint32)leastSignificantBitNdx;
else if (numBits == 0 && leastSignificantBitNdx == 32)
return 0u;
else
{
DE_ASSERT(numBits == 32 && leastSignificantBitNdx == 0);
return 0xFFFFFFFFu;
}
}
DE_INLINE deUint32 deUintMaxValue32 (int numBits)
{
DE_ASSERT(deInRange32(numBits, 1, 32));
if (numBits < 32)
return ((1u<<numBits)-1u);
else
return 0xFFFFFFFFu;
}
DE_INLINE deInt32 deIntMaxValue32 (int numBits)
{
DE_ASSERT(deInRange32(numBits, 1, 32));
if (numBits < 32)
return ((deInt32)1 << (numBits - 1)) - 1;
else
{
/* avoid undefined behavior of int overflow when shifting */
return 0x7FFFFFFF;
}
}
DE_INLINE deInt32 deIntMinValue32 (int numBits)
{
DE_ASSERT(deInRange32(numBits, 1, 32));
if (numBits < 32)
return -((deInt32)1 << (numBits - 1));
else
{
/* avoid undefined behavior of int overflow when shifting */
return (deInt32)(-0x7FFFFFFF - 1);
}
}
DE_INLINE deInt32 deSignExtendTo32 (deInt32 value, int numBits)
{
DE_ASSERT(deInRange32(numBits, 1, 32));
if (numBits < 32)
{
deBool signSet = ((deUint32)value & (1u<<(numBits-1))) != 0;
deUint32 signMask = deBitMask32(numBits, 32-numBits);
DE_ASSERT(((deUint32)value & signMask) == 0u);
return (deInt32)((deUint32)value | (signSet ? signMask : 0u));
}
else
return value;
}
DE_END_EXTERN_C
#endif /* _DEINT32_H */