cutlass_math.h
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#pragma once
#include <cutlass/util/platform.h>
namespace cutlass {
/******************************************************************************
* Static math utilities
******************************************************************************/
template <int N>
struct is_pow2 : platform::integral_constant<bool, (N & (N - 1)) == 0> {};
template <int N, int CurrentVal = N, int Count = 0>
struct log2_down {
enum { value = log2_down<N, (CurrentVal >> 1), Count + 1>::value };
};
// Base case
template <int N, int Count>
struct log2_down<N, 1, Count> {
enum { value = Count };
};
template <int N, int CurrentVal = N, int Count = 0>
struct log2_up {
enum { value = log2_up<N, (CurrentVal >> 1), Count + 1>::value };
};
// Base case
template <int N, int Count>
struct log2_up<N, 1, Count> {
enum { value = ((1 << Count) < N) ? Count + 1 : Count };
};
template <int N>
struct sqrt_est {
enum { value = 1 << (log2_up<N>::value / 2) };
};
template <int Dividend, int Divisor>
struct divide_assert {
enum { value = Dividend / Divisor };
static_assert((Dividend % Divisor == 0), "Not an even multiple");
};
/******************************************************************************
* Rounding
******************************************************************************/
template <typename dividend_t, typename divisor_t>
CUTLASS_HOST_DEVICE dividend_t round_nearest(dividend_t dividend, divisor_t divisor) {
return ((dividend + divisor - 1) / divisor) * divisor;
}
template <typename value_t>
CUTLASS_HOST_DEVICE value_t gcd(value_t a, value_t b) {
for (;;) {
if (a == 0) return b;
b %= a;
if (b == 0) return a;
a %= b;
}
}
template <typename value_t>
CUTLASS_HOST_DEVICE value_t lcm(value_t a, value_t b) {
value_t temp = gcd(a, b);
return temp ? (a / temp * b) : 0;
}
} // namespace cutlass
cutlass::divide_assert::value
Definition: cutlass_math.h:91
cutlass
Definition: convert.h:33
cutlass::log2_down
Definition: cutlass_math.h:51
platform.h
C++ features that may be otherwise unimplemented for CUDA device functions.
cutlass::log2_down::value
Definition: cutlass_math.h:53
cutlass::lcm
CUTLASS_HOST_DEVICE value_t lcm(value_t a, value_t b)
Definition: cutlass_math.h:125
cutlass::round_nearest
CUTLASS_HOST_DEVICE dividend_t round_nearest(dividend_t dividend, divisor_t divisor)
Definition: cutlass_math.h:104
cutlass::log2_up::value
Definition: cutlass_math.h:68
cutlass::platform::integral_constant
std::integral_constant
Definition: platform.h:274
CUTLASS_HOST_DEVICE
#define CUTLASS_HOST_DEVICE
Definition: cutlass.h:46
static_assert
#define static_assert(__e, __m)
Definition: platform.h:145
cutlass::sqrt_est::value
Definition: cutlass_math.h:82
cutlass::gcd
CUTLASS_HOST_DEVICE value_t gcd(value_t a, value_t b)
Definition: cutlass_math.h:112
cutlass::divide_assert
Definition: cutlass_math.h:90
cutlass::log2_up
Definition: cutlass_math.h:66
cutlass::is_pow2
Definition: cutlass_math.h:45
cutlass::sqrt_est
Definition: cutlass_math.h:81