kc3-lang/angle/src/common/mathutil.h

Branch : - branch - main - tag -

• Show log

  Commit

• Author : Arun Patole
  Date : 2015-07-07 18:18:23
  Hash : 551279e5
  Message : Support constant folding of more common built-ins This change adds const folding support for below mentioned common built-ins: - isnan, ininf, floatBitsToInt, floatBitsToUint, intBitsToFloat and uintBitsToFloat BUG=angleproject:913 TEST=angle_unittests(new: MathUtilTest.isNan/inInf), dEQP Tests dEQP-GLES3.functional.shaders.constant_expressions.builtin_functions.common.* (20 more tests started passing with this change) Change-Id: Ifdedb251cd8b183b4999314c0f5de857bc20702f Reviewed-on: https://chromium-review.googlesource.com/283767 Reviewed-by: Olli Etuaho <oetuaho@nvidia.com> Tested-by: Olli Etuaho <oetuaho@nvidia.com> Reviewed-by: Jamie Madill <jmadill@chromium.org>

• src/common/mathutil.h

• //
  // Copyright (c) 2002-2013 The ANGLE Project Authors. All rights reserved.
  // Use of this source code is governed by a BSD-style license that can be
  // found in the LICENSE file.
  //
  
  // mathutil.h: Math and bit manipulation functions.
  
  #ifndef COMMON_MATHUTIL_H_
  #define COMMON_MATHUTIL_H_
  
  #include "common/debug.h"
  #include "common/platform.h"
  
  #include <limits>
  #include <algorithm>
  #include <math.h>
  #include <string.h>
  #include <stdint.h>
  #include <stdlib.h>
  
  namespace gl
  {
  
  const unsigned int Float32One = 0x3F800000;
  const unsigned short Float16One = 0x3C00;
  
  struct Vector4
  {
      Vector4() {}
      Vector4(float x, float y, float z, float w) : x(x), y(y), z(z), w(w) {}
  
      float x;
      float y;
      float z;
      float w;
  };
  
  inline bool isPow2(int x)
  {
      return (x & (x - 1)) == 0 && (x != 0);
  }
  
  inline int log2(int x)
  {
      int r = 0;
      while ((x >> r) > 1) r++;
      return r;
  }
  
  inline unsigned int ceilPow2(unsigned int x)
  {
      if (x != 0) x--;
      x |= x >> 1;
      x |= x >> 2;
      x |= x >> 4;
      x |= x >> 8;
      x |= x >> 16;
      x++;
  
      return x;
  }
  
  inline int clampToInt(unsigned int x)
  {
      return static_cast<int>(std::min(x, static_cast<unsigned int>(std::numeric_limits<int>::max())));
  }
  
  template <typename DestT, typename SrcT>
  inline DestT clampCast(SrcT value)
  {
      // This assumes SrcT can properly represent DestT::min/max
      // Unfortunately we can't use META_ASSERT without C++11 constexpr support
      ASSERT(static_cast<DestT>(static_cast<SrcT>(std::numeric_limits<DestT>::min())) == std::numeric_limits<DestT>::min());
      ASSERT(static_cast<DestT>(static_cast<SrcT>(std::numeric_limits<DestT>::max())) == std::numeric_limits<DestT>::max());
  
      SrcT lo = static_cast<SrcT>(std::numeric_limits<DestT>::min());
      SrcT hi = static_cast<SrcT>(std::numeric_limits<DestT>::max());
      return static_cast<DestT>(value > lo ? (value > hi ? hi : value) : lo);
  }
  
  template<typename T, typename MIN, typename MAX>
  inline T clamp(T x, MIN min, MAX max)
  {
      // Since NaNs fail all comparison tests, a NaN value will default to min
      return x > min ? (x > max ? max : x) : min;
  }
  
  inline float clamp01(float x)
  {
      return clamp(x, 0.0f, 1.0f);
  }
  
  template<const int n>
  inline unsigned int unorm(float x)
  {
      const unsigned int max = 0xFFFFFFFF >> (32 - n);
  
      if (x > 1)
      {
          return max;
      }
      else if (x < 0)
      {
          return 0;
      }
      else
      {
          return (unsigned int)(max * x + 0.5f);
      }
  }
  
  inline bool supportsSSE2()
  {
  #if defined(ANGLE_PLATFORM_WINDOWS) && !defined(_M_ARM)
      static bool checked = false;
      static bool supports = false;
  
      if (checked)
      {
          return supports;
      }
  
      int info[4];
      __cpuid(info, 0);
  
      if (info[0] >= 1)
      {
          __cpuid(info, 1);
  
          supports = (info[3] >> 26) & 1;
      }
  
      checked = true;
  
      return supports;
  #else
      UNIMPLEMENTED();
      return false;
  #endif
  }
  
  template <typename destType, typename sourceType>
  destType bitCast(const sourceType &source)
  {
      size_t copySize = std::min(sizeof(destType), sizeof(sourceType));
      destType output;
      memcpy(&output, &source, copySize);
      return output;
  }
  
  inline unsigned short float32ToFloat16(float fp32)
  {
      unsigned int fp32i = (unsigned int&)fp32;
      unsigned int sign = (fp32i & 0x80000000) >> 16;
      unsigned int abs = fp32i & 0x7FFFFFFF;
  
      if(abs > 0x47FFEFFF)   // Infinity
      {
          return static_cast<unsigned short>(sign | 0x7FFF);
      }
      else if(abs < 0x38800000)   // Denormal
      {
          unsigned int mantissa = (abs & 0x007FFFFF) | 0x00800000;
          int e = 113 - (abs >> 23);
  
          if(e < 24)
          {
              abs = mantissa >> e;
          }
          else
          {
              abs = 0;
          }
  
          return static_cast<unsigned short>(sign | (abs + 0x00000FFF + ((abs >> 13) & 1)) >> 13);
      }
      else
      {
          return static_cast<unsigned short>(sign | (abs + 0xC8000000 + 0x00000FFF + ((abs >> 13) & 1)) >> 13);
      }
  }
  
  float float16ToFloat32(unsigned short h);
  
  unsigned int convertRGBFloatsTo999E5(float red, float green, float blue);
  void convert999E5toRGBFloats(unsigned int input, float *red, float *green, float *blue);
  
  inline unsigned short float32ToFloat11(float fp32)
  {
      const unsigned int float32MantissaMask = 0x7FFFFF;
      const unsigned int float32ExponentMask = 0x7F800000;
      const unsigned int float32SignMask = 0x80000000;
      const unsigned int float32ValueMask = ~float32SignMask;
      const unsigned int float32ExponentFirstBit = 23;
      const unsigned int float32ExponentBias = 127;
  
      const unsigned short float11Max = 0x7BF;
      const unsigned short float11MantissaMask = 0x3F;
      const unsigned short float11ExponentMask = 0x7C0;
      const unsigned short float11BitMask = 0x7FF;
      const unsigned int float11ExponentBias = 14;
  
      const unsigned int float32Maxfloat11 = 0x477E0000;
      const unsigned int float32Minfloat11 = 0x38800000;
  
      const unsigned int float32Bits = bitCast<unsigned int>(fp32);
      const bool float32Sign = (float32Bits & float32SignMask) == float32SignMask;
  
      unsigned int float32Val = float32Bits & float32ValueMask;
  
      if ((float32Val & float32ExponentMask) == float32ExponentMask)
      {
          // INF or NAN
          if ((float32Val & float32MantissaMask) != 0)
          {
              return float11ExponentMask | (((float32Val >> 17) | (float32Val >> 11) | (float32Val >> 6) | (float32Val)) & float11MantissaMask);
          }
          else if (float32Sign)
          {
              // -INF is clamped to 0 since float11 is positive only
              return 0;
          }
          else
          {
              return float11ExponentMask;
          }
      }
      else if (float32Sign)
      {
          // float11 is positive only, so clamp to zero
          return 0;
      }
      else if (float32Val > float32Maxfloat11)
      {
          // The number is too large to be represented as a float11, set to max
          return float11Max;
      }
      else
      {
          if (float32Val < float32Minfloat11)
          {
              // The number is too small to be represented as a normalized float11
              // Convert it to a denormalized value.
              const unsigned int shift = (float32ExponentBias - float11ExponentBias) - (float32Val >> float32ExponentFirstBit);
              float32Val = ((1 << float32ExponentFirstBit) | (float32Val & float32MantissaMask)) >> shift;
          }
          else
          {
              // Rebias the exponent to represent the value as a normalized float11
              float32Val += 0xC8000000;
          }
  
          return ((float32Val + 0xFFFF + ((float32Val >> 17) & 1)) >> 17) & float11BitMask;
      }
  }
  
  inline unsigned short float32ToFloat10(float fp32)
  {
      const unsigned int float32MantissaMask = 0x7FFFFF;
      const unsigned int float32ExponentMask = 0x7F800000;
      const unsigned int float32SignMask = 0x80000000;
      const unsigned int float32ValueMask = ~float32SignMask;
      const unsigned int float32ExponentFirstBit = 23;
      const unsigned int float32ExponentBias = 127;
  
      const unsigned short float10Max = 0x3DF;
      const unsigned short float10MantissaMask = 0x1F;
      const unsigned short float10ExponentMask = 0x3E0;
      const unsigned short float10BitMask = 0x3FF;
      const unsigned int float10ExponentBias = 14;
  
      const unsigned int float32Maxfloat10 = 0x477C0000;
      const unsigned int float32Minfloat10 = 0x38800000;
  
      const unsigned int float32Bits = bitCast<unsigned int>(fp32);
      const bool float32Sign = (float32Bits & float32SignMask) == float32SignMask;
  
      unsigned int float32Val = float32Bits & float32ValueMask;
  
      if ((float32Val & float32ExponentMask) == float32ExponentMask)
      {
          // INF or NAN
          if ((float32Val & float32MantissaMask) != 0)
          {
              return float10ExponentMask | (((float32Val >> 18) | (float32Val >> 13) | (float32Val >> 3) | (float32Val)) & float10MantissaMask);
          }
          else if (float32Sign)
          {
              // -INF is clamped to 0 since float11 is positive only
              return 0;
          }
          else
          {
              return float10ExponentMask;
          }
      }
      else if (float32Sign)
      {
          // float10 is positive only, so clamp to zero
          return 0;
      }
      else if (float32Val > float32Maxfloat10)
      {
          // The number is too large to be represented as a float11, set to max
          return float10Max;
      }
      else
      {
          if (float32Val < float32Minfloat10)
          {
              // The number is too small to be represented as a normalized float11
              // Convert it to a denormalized value.
              const unsigned int shift = (float32ExponentBias - float10ExponentBias) - (float32Val >> float32ExponentFirstBit);
              float32Val = ((1 << float32ExponentFirstBit) | (float32Val & float32MantissaMask)) >> shift;
          }
          else
          {
              // Rebias the exponent to represent the value as a normalized float11
              float32Val += 0xC8000000;
          }
  
          return ((float32Val + 0x1FFFF + ((float32Val >> 18) & 1)) >> 18) & float10BitMask;
      }
  }
  
  inline float float11ToFloat32(unsigned short fp11)
  {
      unsigned short exponent = (fp11 >> 6) & 0x1F;
      unsigned short mantissa = fp11 & 0x3F;
  
      if (exponent == 0x1F)
      {
          // INF or NAN
          return bitCast<float>(0x7f800000 | (mantissa << 17));
      }
      else
      {
          if (exponent != 0)
          {
              // normalized
          }
          else if (mantissa != 0)
          {
              // The value is denormalized
              exponent = 1;
  
              do
              {
                  exponent--;
                  mantissa <<= 1;
              }
              while ((mantissa & 0x40) == 0);
  
              mantissa = mantissa & 0x3F;
          }
          else // The value is zero
          {
              exponent = static_cast<unsigned short>(-112);
          }
  
          return bitCast<float>(((exponent + 112) << 23) | (mantissa << 17));
      }
  }
  
  inline float float10ToFloat32(unsigned short fp11)
  {
      unsigned short exponent = (fp11 >> 5) & 0x1F;
      unsigned short mantissa = fp11 & 0x1F;
  
      if (exponent == 0x1F)
      {
          // INF or NAN
          return bitCast<float>(0x7f800000 | (mantissa << 17));
      }
      else
      {
          if (exponent != 0)
          {
              // normalized
          }
          else if (mantissa != 0)
          {
              // The value is denormalized
              exponent = 1;
  
              do
              {
                  exponent--;
                  mantissa <<= 1;
              }
              while ((mantissa & 0x20) == 0);
  
              mantissa = mantissa & 0x1F;
          }
          else // The value is zero
          {
              exponent = static_cast<unsigned short>(-112);
          }
  
          return bitCast<float>(((exponent + 112) << 23) | (mantissa << 18));
      }
  }
  
  template <typename T>
  inline float normalizedToFloat(T input)
  {
      static_assert(std::numeric_limits<T>::is_integer, "T must be an integer.");
  
      const float inverseMax = 1.0f / std::numeric_limits<T>::max();
      return input * inverseMax;
  }
  
  template <unsigned int inputBitCount, typename T>
  inline float normalizedToFloat(T input)
  {
      static_assert(std::numeric_limits<T>::is_integer, "T must be an integer.");
      static_assert(inputBitCount < (sizeof(T) * 8), "T must have more bits than inputBitCount.");
  
      const float inverseMax = 1.0f / ((1 << inputBitCount) - 1);
      return input * inverseMax;
  }
  
  template <typename T>
  inline T floatToNormalized(float input)
  {
      return static_cast<T>(std::numeric_limits<T>::max() * input + 0.5f);
  }
  
  template <unsigned int outputBitCount, typename T>
  inline T floatToNormalized(float input)
  {
      static_assert(outputBitCount < (sizeof(T) * 8), "T must have more bits than outputBitCount.");
      return static_cast<T>(((1 << outputBitCount) - 1) * input + 0.5f);
  }
  
  template <unsigned int inputBitCount, unsigned int inputBitStart, typename T>
  inline T getShiftedData(T input)
  {
      static_assert(inputBitCount + inputBitStart <= (sizeof(T) * 8),
                    "T must have at least as many bits as inputBitCount + inputBitStart.");
      const T mask = (1 << inputBitCount) - 1;
      return (input >> inputBitStart) & mask;
  }
  
  template <unsigned int inputBitCount, unsigned int inputBitStart, typename T>
  inline T shiftData(T input)
  {
      static_assert(inputBitCount + inputBitStart <= (sizeof(T) * 8),
                    "T must have at least as many bits as inputBitCount + inputBitStart.");
      const T mask = (1 << inputBitCount) - 1;
      return (input & mask) << inputBitStart;
  }
  
  
  inline unsigned char average(unsigned char a, unsigned char b)
  {
      return ((a ^ b) >> 1) + (a & b);
  }
  
  inline signed char average(signed char a, signed char b)
  {
      return ((short)a + (short)b) / 2;
  }
  
  inline unsigned short average(unsigned short a, unsigned short b)
  {
      return ((a ^ b) >> 1) + (a & b);
  }
  
  inline signed short average(signed short a, signed short b)
  {
      return ((int)a + (int)b) / 2;
  }
  
  inline unsigned int average(unsigned int a, unsigned int b)
  {
      return ((a ^ b) >> 1) + (a & b);
  }
  
  inline signed int average(signed int a, signed int b)
  {
      return ((long long)a + (long long)b) / 2;
  }
  
  inline float average(float a, float b)
  {
      return (a + b) * 0.5f;
  }
  
  inline unsigned short averageHalfFloat(unsigned short a, unsigned short b)
  {
      return float32ToFloat16((float16ToFloat32(a) + float16ToFloat32(b)) * 0.5f);
  }
  
  inline unsigned int averageFloat11(unsigned int a, unsigned int b)
  {
      return float32ToFloat11((float11ToFloat32(static_cast<unsigned short>(a)) + float11ToFloat32(static_cast<unsigned short>(b))) * 0.5f);
  }
  
  inline unsigned int averageFloat10(unsigned int a, unsigned int b)
  {
      return float32ToFloat10((float10ToFloat32(static_cast<unsigned short>(a)) + float10ToFloat32(static_cast<unsigned short>(b))) * 0.5f);
  }
  
  // Represents intervals of the type [a, b)
  template <typename T>
  struct Range
  {
      Range() {}
      Range(T lo, T hi) : start(lo), end(hi) { ASSERT(lo <= hi); }
  
      T start;
      T end;
  
      T length() const { return end - start; }
  
      bool intersects(Range<T> other)
      {
          if (start <= other.start)
          {
              return other.start < end;
          }
          else
          {
              return start < other.end;
          }
      }
  
      void extend(T value)
      {
          start = value > start ? value : start;
          end = value < end ? value : end;
      }
  
      bool empty() const
      {
          return end <= start;
      }
  };
  
  typedef Range<int> RangeI;
  typedef Range<unsigned int> RangeUI;
  
  // First, both normalized floating-point values are converted into 16-bit integer values.
  // Then, the results are packed into the returned 32-bit unsigned integer.
  // The first float value will be written to the least significant bits of the output;
  // the last float value will be written to the most significant bits.
  // The conversion of each value to fixed point is done as follows :
  // packSnorm2x16 : round(clamp(c, -1, +1) * 32767.0)
  inline uint32_t packSnorm2x16(float f1, float f2)
  {
      uint16_t leastSignificantBits = static_cast<uint16_t>(roundf(clamp(f1, -1.0f, 1.0f) * 32767.0f));
      uint16_t mostSignificantBits = static_cast<uint16_t>(roundf(clamp(f2, -1.0f, 1.0f) * 32767.0f));
      return static_cast<uint32_t>(mostSignificantBits) << 16 | static_cast<uint32_t>(leastSignificantBits);
  }
  
  // First, unpacks a single 32-bit unsigned integer u into a pair of 16-bit unsigned integers. Then, each
  // component is converted to a normalized floating-point value to generate the returned two float values.
  // The first float value will be extracted from the least significant bits of the input;
  // the last float value will be extracted from the most-significant bits.
  // The conversion for unpacked fixed-point value to floating point is done as follows:
  // unpackSnorm2x16 : clamp(f / 32767.0, -1, +1)
  inline void unpackSnorm2x16(uint32_t u, float *f1, float *f2)
  {
      int16_t leastSignificantBits = static_cast<int16_t>(u & 0xFFFF);
      int16_t mostSignificantBits = static_cast<int16_t>(u >> 16);
      *f1 = clamp(static_cast<float>(leastSignificantBits) / 32767.0f, -1.0f, 1.0f);
      *f2 = clamp(static_cast<float>(mostSignificantBits) / 32767.0f, -1.0f, 1.0f);
  }
  
  // First, both normalized floating-point values are converted into 16-bit integer values.
  // Then, the results are packed into the returned 32-bit unsigned integer.
  // The first float value will be written to the least significant bits of the output;
  // the last float value will be written to the most significant bits.
  // The conversion of each value to fixed point is done as follows:
  // packUnorm2x16 : round(clamp(c, 0, +1) * 65535.0)
  inline uint32_t packUnorm2x16(float f1, float f2)
  {
      uint16_t leastSignificantBits = static_cast<uint16_t>(roundf(clamp(f1, 0.0f, 1.0f) * 65535.0f));
      uint16_t mostSignificantBits = static_cast<uint16_t>(roundf(clamp(f2, 0.0f, 1.0f) * 65535.0f));
      return static_cast<uint32_t>(mostSignificantBits) << 16 | static_cast<uint32_t>(leastSignificantBits);
  }
  
  // First, unpacks a single 32-bit unsigned integer u into a pair of 16-bit unsigned integers. Then, each
  // component is converted to a normalized floating-point value to generate the returned two float values.
  // The first float value will be extracted from the least significant bits of the input;
  // the last float value will be extracted from the most-significant bits.
  // The conversion for unpacked fixed-point value to floating point is done as follows:
  // unpackUnorm2x16 : f / 65535.0
  inline void unpackUnorm2x16(uint32_t u, float *f1, float *f2)
  {
      uint16_t leastSignificantBits = static_cast<uint16_t>(u & 0xFFFF);
      uint16_t mostSignificantBits = static_cast<uint16_t>(u >> 16);
      *f1 = static_cast<float>(leastSignificantBits) / 65535.0f;
      *f2 = static_cast<float>(mostSignificantBits) / 65535.0f;
  }
  
  // Returns an unsigned integer obtained by converting the two floating-point values to the 16-bit
  // floating-point representation found in the OpenGL ES Specification, and then packing these
  // two 16-bit integers into a 32-bit unsigned integer.
  // f1: The 16 least-significant bits of the result;
  // f2: The 16 most-significant bits.
  inline uint32_t packHalf2x16(float f1, float f2)
  {
      uint16_t leastSignificantBits = static_cast<uint16_t>(float32ToFloat16(f1));
      uint16_t mostSignificantBits = static_cast<uint16_t>(float32ToFloat16(f2));
      return static_cast<uint32_t>(mostSignificantBits) << 16 | static_cast<uint32_t>(leastSignificantBits);
  }
  
  // Returns two floating-point values obtained by unpacking a 32-bit unsigned integer into a pair of 16-bit values,
  // interpreting those values as 16-bit floating-point numbers according to the OpenGL ES Specification,
  // and converting them to 32-bit floating-point values.
  // The first float value is obtained from the 16 least-significant bits of u;
  // the second component is obtained from the 16 most-significant bits of u.
  inline void unpackHalf2x16(uint32_t u, float *f1, float *f2)
  {
      uint16_t leastSignificantBits = static_cast<uint16_t>(u & 0xFFFF);
      uint16_t mostSignificantBits = static_cast<uint16_t>(u >> 16);
  
      *f1 = float16ToFloat32(leastSignificantBits);
      *f2 = float16ToFloat32(mostSignificantBits);
  }
  
  // Returns whether the argument is Not a Number.
  // IEEE 754 single precision NaN representation: Exponent(8 bits) - 255, Mantissa(23 bits) - non-zero.
  inline bool isNaN(float f)
  {
      // Exponent mask: ((1u << 8) - 1u) << 23 = 0x7f800000u
      // Mantissa mask: ((1u << 23) - 1u) = 0x7fffffu
      return ((bitCast<uint32_t>(f) & 0x7f800000u) == 0x7f800000u) && (bitCast<uint32_t>(f) & 0x7fffffu);
  }
  
  // Returns whether the argument is infinity.
  // IEEE 754 single precision infinity representation: Exponent(8 bits) - 255, Mantissa(23 bits) - zero.
  inline bool isInf(float f)
  {
      // Exponent mask: ((1u << 8) - 1u) << 23 = 0x7f800000u
      // Mantissa mask: ((1u << 23) - 1u) = 0x7fffffu
      return ((bitCast<uint32_t>(f) & 0x7f800000u) == 0x7f800000u) && !(bitCast<uint32_t>(f) & 0x7fffffu);
  }
  
  }
  
  namespace rx
  {
  
  template <typename T>
  T roundUp(const T value, const T alignment)
  {
      return value + alignment - 1 - (value - 1) % alignment;
  }
  
  inline unsigned int UnsignedCeilDivide(unsigned int value, unsigned int divisor)
  {
      unsigned int divided = value / divisor;
      return (divided + ((value % divisor == 0) ? 0 : 1));
  }
  
  template <class T>
  inline bool IsUnsignedAdditionSafe(T lhs, T rhs)
  {
      static_assert(!std::numeric_limits<T>::is_signed, "T must be unsigned.");
      return (rhs <= std::numeric_limits<T>::max() - lhs);
  }
  
  template <class T>
  inline bool IsUnsignedMultiplicationSafe(T lhs, T rhs)
  {
      static_assert(!std::numeric_limits<T>::is_signed, "T must be unsigned.");
      return (lhs == T(0) || rhs == T(0) || (rhs <= std::numeric_limits<T>::max() / lhs));
  }
  
  template <class SmallIntT, class BigIntT>
  inline bool IsIntegerCastSafe(BigIntT bigValue)
  {
      return (static_cast<BigIntT>(static_cast<SmallIntT>(bigValue)) == bigValue);
  }
  
  #if defined(_MSC_VER)
  
  #define ANGLE_ROTL(x,y) _rotl(x,y)
  #define ANGLE_ROTR16(x,y) _rotr16(x,y)
  
  #else
  
  inline uint32_t RotL(uint32_t x, int8_t r)
  {
      return (x << r) | (x >> (32 - r));
  }
  
  inline uint16_t RotR16(uint16_t x, int8_t r)
  {
      return (x >> r) | (x << (16 - r));
  }
  
  #define ANGLE_ROTL(x,y) RotL(x,y)
  #define ANGLE_ROTR16(x,y) RotR16(x,y)
  
  #endif // namespace rx
  
  }
  
  #endif   // COMMON_MATHUTIL_H_