/**
* \file dnn/src/cuda/integer_subbyte_utils.cuh
* MegEngine is Licensed under the Apache License, Version 2.0 (the "License")
*
* Copyright (c) 2014-2021 Megvii Inc. All rights reserved.
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT ARRANTIES OR CONDITIONS OF ANY KIND, either express or
* implied.
*/
#if MEGDNN_CC_CUDA
#pragma once
#include "src/cuda/utils.cuh"
namespace megdnn {
namespace cuda {
namespace integer_subbyte {
template <bool signedness>
struct integer_trait;
template <>
struct integer_trait<true> {
using type = int;
};
template <>
struct integer_trait<false> {
using type = unsigned;
};
MEGDNN_DEVICE __forceinline__ static int transform_int8_to_int4x8(
int s0, int s1, int s2, int s3, int s4, int s5, int s6, int s7) {
unsigned out;
#if __CUDA_ARCH__ >= 750 && \
((__CUDACC_VER_MAJOR__ > 10) || \
((__CUDACC_VER_MAJOR__ >= 10) && (__CUDACC_VER_MINOR__ >= 2)))
asm volatile(
"{ .reg .u32 r4;"
"cvt.pack.sat.s4.s32.b32 r4, %8, %7, 0;"
"cvt.pack.sat.s4.s32.b32 r4, %6, %5, r4;"
"cvt.pack.sat.s4.s32.b32 r4, %4, %3, r4;"
"cvt.pack.sat.s4.s32.b32 %0, %2, %1, r4;"
"}"
: "=r"(out)
: "r"(s0), "r"(s1), "r"(s2), "r"(s3), "r"(s4), "r"(s5), "r"(s6), "r"(s7));
#else
#define CVT_SAT_S4_S32(r, bits) \
r = r <= -8 ? -8 : r; \
r = r > 7 ? 7 : r; \
r = (((unsigned)r & 0xf) << bits);
CVT_SAT_S4_S32(s0, 0)
CVT_SAT_S4_S32(s1, 4)
CVT_SAT_S4_S32(s2, 8)
CVT_SAT_S4_S32(s3, 12)
CVT_SAT_S4_S32(s4, 16)
CVT_SAT_S4_S32(s5, 20)
CVT_SAT_S4_S32(s6, 24)
CVT_SAT_S4_S32(s7, 28)
out = s0 + s1 + s2 + s3 + s4 + s5 + s6 + s7;
#undef CVT_SAT_S4_S32
#endif
return reinterpret_cast<int const&>(out);
}
MEGDNN_DEVICE __forceinline__ static int transform_int8_to_uint4x8(
int s0, int s1, int s2, int s3, int s4, int s5, int s6, int s7) {
unsigned out;
#if __CUDA_ARCH__ >= 750 && \
((__CUDACC_VER_MAJOR__ > 10) || \
((__CUDACC_VER_MAJOR__ >= 10) && (__CUDACC_VER_MINOR__ >= 2)))
asm volatile(
"{ .reg .u32 r4;"
"cvt.pack.sat.u4.s32.b32 r4, %8, %7, 0;"
"cvt.pack.sat.u4.s32.b32 r4, %6, %5, r4;"
"cvt.pack.sat.u4.s32.b32 r4, %4, %3, r4;"
"cvt.pack.sat.u4.s32.b32 %0, %2, %1, r4;"
"}"
: "=r"(out)
: "r"(s0), "r"(s1), "r"(s2), "r"(s3), "r"(s4), "r"(s5), "r"(s6), "r"(s7));
#else
#define CVT_SAT_U4_S32(r, bits) \
r = r <= 0 ? 0 : r; \
r = r > 15 ? 15 : r; \
r = (((unsigned)r & 0xf) << bits);
CVT_SAT_U4_S32(s0, 0)
CVT_SAT_U4_S32(s1, 4)
CVT_SAT_U4_S32(s2, 8)
CVT_SAT_U4_S32(s3, 12)
CVT_SAT_U4_S32(s4, 16)
CVT_SAT_U4_S32(s5, 20)
CVT_SAT_U4_S32(s6, 24)
CVT_SAT_U4_S32(s7, 28)
out = s0 + s1 + s2 + s3 + s4 + s5 + s6 + s7;
#undef CVT_SAT_U4_S32
#endif
return reinterpret_cast<int const&>(out);
}
template <bool signedness, typename T>
MEGDNN_DEVICE __forceinline__ static int unpack_integer_4bits(T storage, int bits) {
//! size in bits of 32 bit integer - 4 bits
static constexpr int shift = 28;
using type = typename integer_trait<signedness>::type;
unsigned intermediate = static_cast<unsigned>(storage);
type result = reinterpret_cast<type&>(intermediate);
return (result << (shift - bits)) >> shift;
}
template <bool signedness>
MEGDNN_DEVICE __forceinline__ static void transform_b4x8_to_int8(
int (&result)[8], const int& source) {
#pragma unroll
for (int i = 0; i < 8; i++) {
result[i] = unpack_integer_4bits<signedness>(
reinterpret_cast<unsigned const&>(source), (i << 2));
}
}
template <bool signedness>
MEGDNN_DEVICE __forceinline__ static void transform_b4x2_to_int8(
int (&result)[2], const uint8_t& source) {
result[0] = unpack_integer_4bits<signedness>(source, 0);
result[1] = unpack_integer_4bits<signedness>(source, 4);
}
template <bool signedness>
MEGDNN_DEVICE __forceinline__ static int transform_int8_to_b4x8(
int s0, int s1, int s2, int s3, int s4, int s5, int s6, int s7) {
if (signedness) {
return transform_int8_to_int4x8(s0, s1, s2, s3, s4, s5, s6, s7);
} else {
return transform_int8_to_uint4x8(s0, s1, s2, s3, s4, s5, s6, s7);
}
}
} // namespace integer_subbyte
} // namespace cuda
} // namespace megdnn
#endif
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