| // Copyright (c) Facebook, Inc. and its affiliates. |
| // All rights reserved. |
| // |
| // Copyright 2019 Google LLC |
| // |
| // This source code is licensed under the BSD-style license found in the |
| // LICENSE file in the root directory of this source tree. |
| |
| #include <assert.h> |
| #include <stdint.h> |
| |
| #include <emmintrin.h> |
| |
| #include <fp16/bitcasts.h> |
| |
| #include <xnnpack/requantization-stubs.h> |
| |
| #include "gemmlowp-requantization.h" |
| |
| |
| void xnn_requantize_gemmlowp__sse2( |
| size_t n, |
| const int32_t* input, |
| float scale, |
| uint8_t zero_point, |
| uint8_t qmin, |
| uint8_t qmax, |
| uint8_t* output) |
| { |
| assert(n % 16 == 0); |
| assert(scale < 1.0f); |
| assert(scale >= 0x1.0p-32f); |
| |
| const uint32_t scale_bits = fp32_to_bits(scale); |
| |
| // Compute requantization parameters. |
| const uint32_t multiplier = ((scale_bits & UINT32_C(0x007FFFFF)) | UINT32_C(0x00800000)) << 7; |
| const int32_t exponent = (fp32_to_bits(scale) >> 23) - 127 - 23 - 7; |
| const int32_t shift = -(32 /* using high 32 bits in VQRDMUL */ - 1 /* doubling in VQRDMUL */ + exponent); |
| |
| const __m128i vmultiplier = _mm_set1_epi32(multiplier); |
| const __m128i vzero_point = _mm_set1_epi16((short) (uint16_t) zero_point); |
| const __m128i vqmin = _mm_set1_epi8((char) qmin); |
| const __m128i vqmax = _mm_set1_epi8((char) qmax); |
| for (; n != 0; n -= 16) { |
| const __m128i x = _mm_loadu_si128((const __m128i*) input); |
| const __m128i y = _mm_loadu_si128((const __m128i*) (input + 4)); |
| const __m128i z = _mm_loadu_si128((const __m128i*) (input + 8)); |
| const __m128i w = _mm_loadu_si128((const __m128i*) (input + 12)); |
| input += 16; |
| |
| const __m128i x_product = gemmlowp_sse_vqrdmulh_s32(x, vmultiplier); |
| const __m128i y_product = gemmlowp_sse_vqrdmulh_s32(y, vmultiplier); |
| const __m128i z_product = gemmlowp_sse_vqrdmulh_s32(z, vmultiplier); |
| const __m128i w_product = gemmlowp_sse_vqrdmulh_s32(w, vmultiplier); |
| |
| const __m128i x_scaled = gemmlowp_sse_rdivbypo2_s32(x_product, shift); |
| const __m128i y_scaled = gemmlowp_sse_rdivbypo2_s32(y_product, shift); |
| const __m128i z_scaled = gemmlowp_sse_rdivbypo2_s32(z_product, shift); |
| const __m128i w_scaled = gemmlowp_sse_rdivbypo2_s32(w_product, shift); |
| |
| const __m128i xy_packed = _mm_adds_epi16(_mm_packs_epi32(x_scaled, y_scaled), vzero_point); |
| const __m128i zw_packed = _mm_adds_epi16(_mm_packs_epi32(z_scaled, w_scaled), vzero_point); |
| const __m128i xyzw_packed = _mm_packus_epi16(xy_packed, zw_packed); |
| const __m128i xyzw_clamped = _mm_max_epu8(_mm_min_epu8(xyzw_packed, vqmax), vqmin); |
| |
| _mm_storeu_si128((__m128i*) output, xyzw_clamped); |
| output += 16; |
| } |
| } |