binary32.hh

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#ifndef __ARCH_AMDGPU_COMMON_DTYPE_BINARY32_HH__
#define __ARCH_AMDGPU_COMMON_DTYPE_BINARY32_HH__
 
namespace gem5
{
 
namespace AMDGPU
{
 
// Same as IEEE 754 binary 32 - Microscaling types are converted to/from
// this format by default. For now as there do not seem to be any MI300
// instructions operating directly on the types (i.e., they all cast to FP32
// first and then perform arithmetic operations).
typedef union binary32_u
{
    enum bitSizes
    {
        ebits = 8,
        mbits = 23,
        sbits = 1,
        bias = 127,
 
        inf = 0x7f800000,
        nan = 0x7f800100,
        max = 0x7f7fffff
    };
 
    uint32_t storage;
    float    fp32;
    struct
    {
        unsigned mant : 23;
        unsigned exp  : 8;
        unsigned sign : 1;
    };
 
    // To help with stdlib functions with T = float.
    operator float() const
    {
        return fp32;
    }
} binary32;
static_assert(sizeof(binary32) == 4);
 
} // namespace AMDGPU
 
} // namespace gem5
 
namespace std
{
 
template<>
class numeric_limits<gem5::AMDGPU::binary32>
{
  public:
    static constexpr bool has_quiet_NaN = true;
    static gem5::AMDGPU::binary32 quiet_NaN()
    {
        gem5::AMDGPU::binary32 tmp;
        tmp.fp32 = std::numeric_limits<float>::quiet_NaN();
        return tmp;
    }
 
    static constexpr bool has_infinity = true;
    static gem5::AMDGPU::binary32 infinity()
    {
        gem5::AMDGPU::binary32 tmp;
        tmp.fp32 = std::numeric_limits<float>::infinity();
        return tmp;
    }
 
    static gem5::AMDGPU::binary32 max()
    {
        gem5::AMDGPU::binary32 tmp;
        tmp.fp32 = std::numeric_limits<float>::max();
        return tmp;
    }
};
 
} // namespace std
 
#endif // __ARCH_AMDGPU_COMMON_DTYPE_BINARY32_HH__