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Diffstat (limited to 'third_party/libwebrtc/common_audio/signal_processing/downsample_fast_neon.c')
-rw-r--r-- | third_party/libwebrtc/common_audio/signal_processing/downsample_fast_neon.c | 217 |
1 files changed, 217 insertions, 0 deletions
diff --git a/third_party/libwebrtc/common_audio/signal_processing/downsample_fast_neon.c b/third_party/libwebrtc/common_audio/signal_processing/downsample_fast_neon.c new file mode 100644 index 0000000000..36fc0c8aee --- /dev/null +++ b/third_party/libwebrtc/common_audio/signal_processing/downsample_fast_neon.c @@ -0,0 +1,217 @@ +/* + * Copyright (c) 2014 The WebRTC 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 in the root of the source + * tree. An additional intellectual property rights grant can be found + * in the file PATENTS. All contributing project authors may + * be found in the AUTHORS file in the root of the source tree. + */ + +#include "common_audio/signal_processing/include/signal_processing_library.h" + +#include <arm_neon.h> + +// NEON intrinsics version of WebRtcSpl_DownsampleFast() +// for ARM 32-bit/64-bit platforms. +int WebRtcSpl_DownsampleFastNeon(const int16_t* data_in, + size_t data_in_length, + int16_t* data_out, + size_t data_out_length, + const int16_t* __restrict coefficients, + size_t coefficients_length, + int factor, + size_t delay) { + size_t i = 0; + size_t j = 0; + int32_t out_s32 = 0; + size_t endpos = delay + factor * (data_out_length - 1) + 1; + size_t res = data_out_length & 0x7; + size_t endpos1 = endpos - factor * res; + + // Return error if any of the running conditions doesn't meet. + if (data_out_length == 0 || coefficients_length == 0 + || data_in_length < endpos) { + return -1; + } + + // First part, unroll the loop 8 times, with 3 subcases + // (factor == 2, 4, others). + switch (factor) { + case 2: { + for (i = delay; i < endpos1; i += 16) { + // Round value, 0.5 in Q12. + int32x4_t out32x4_0 = vdupq_n_s32(2048); + int32x4_t out32x4_1 = vdupq_n_s32(2048); + +#if defined(WEBRTC_ARCH_ARM64) + // Unroll the loop 2 times. + for (j = 0; j < coefficients_length - 1; j += 2) { + int32x2_t coeff32 = vld1_dup_s32((int32_t*)&coefficients[j]); + int16x4_t coeff16x4 = vreinterpret_s16_s32(coeff32); + int16x8x2_t in16x8x2 = vld2q_s16(&data_in[i - j - 1]); + + // Mul and accumulate low 64-bit data. + int16x4_t in16x4_0 = vget_low_s16(in16x8x2.val[0]); + int16x4_t in16x4_1 = vget_low_s16(in16x8x2.val[1]); + out32x4_0 = vmlal_lane_s16(out32x4_0, in16x4_0, coeff16x4, 1); + out32x4_0 = vmlal_lane_s16(out32x4_0, in16x4_1, coeff16x4, 0); + + // Mul and accumulate high 64-bit data. + // TODO: vget_high_s16 need extra cost on ARM64. This could be + // replaced by vmlal_high_lane_s16. But for the interface of + // vmlal_high_lane_s16, there is a bug in gcc 4.9. + // This issue need to be tracked in the future. + int16x4_t in16x4_2 = vget_high_s16(in16x8x2.val[0]); + int16x4_t in16x4_3 = vget_high_s16(in16x8x2.val[1]); + out32x4_1 = vmlal_lane_s16(out32x4_1, in16x4_2, coeff16x4, 1); + out32x4_1 = vmlal_lane_s16(out32x4_1, in16x4_3, coeff16x4, 0); + } + + for (; j < coefficients_length; j++) { + int16x4_t coeff16x4 = vld1_dup_s16(&coefficients[j]); + int16x8x2_t in16x8x2 = vld2q_s16(&data_in[i - j]); + + // Mul and accumulate low 64-bit data. + int16x4_t in16x4_0 = vget_low_s16(in16x8x2.val[0]); + out32x4_0 = vmlal_lane_s16(out32x4_0, in16x4_0, coeff16x4, 0); + + // Mul and accumulate high 64-bit data. + // TODO: vget_high_s16 need extra cost on ARM64. This could be + // replaced by vmlal_high_lane_s16. But for the interface of + // vmlal_high_lane_s16, there is a bug in gcc 4.9. + // This issue need to be tracked in the future. + int16x4_t in16x4_1 = vget_high_s16(in16x8x2.val[0]); + out32x4_1 = vmlal_lane_s16(out32x4_1, in16x4_1, coeff16x4, 0); + } +#else + // On ARMv7, the loop unrolling 2 times results in performance + // regression. + for (j = 0; j < coefficients_length; j++) { + int16x4_t coeff16x4 = vld1_dup_s16(&coefficients[j]); + int16x8x2_t in16x8x2 = vld2q_s16(&data_in[i - j]); + + // Mul and accumulate. + int16x4_t in16x4_0 = vget_low_s16(in16x8x2.val[0]); + int16x4_t in16x4_1 = vget_high_s16(in16x8x2.val[0]); + out32x4_0 = vmlal_lane_s16(out32x4_0, in16x4_0, coeff16x4, 0); + out32x4_1 = vmlal_lane_s16(out32x4_1, in16x4_1, coeff16x4, 0); + } +#endif + + // Saturate and store the output. + int16x4_t out16x4_0 = vqshrn_n_s32(out32x4_0, 12); + int16x4_t out16x4_1 = vqshrn_n_s32(out32x4_1, 12); + vst1q_s16(data_out, vcombine_s16(out16x4_0, out16x4_1)); + data_out += 8; + } + break; + } + case 4: { + for (i = delay; i < endpos1; i += 32) { + // Round value, 0.5 in Q12. + int32x4_t out32x4_0 = vdupq_n_s32(2048); + int32x4_t out32x4_1 = vdupq_n_s32(2048); + + // Unroll the loop 4 times. + for (j = 0; j < coefficients_length - 3; j += 4) { + int16x4_t coeff16x4 = vld1_s16(&coefficients[j]); + int16x8x4_t in16x8x4 = vld4q_s16(&data_in[i - j - 3]); + + // Mul and accumulate low 64-bit data. + int16x4_t in16x4_0 = vget_low_s16(in16x8x4.val[0]); + int16x4_t in16x4_2 = vget_low_s16(in16x8x4.val[1]); + int16x4_t in16x4_4 = vget_low_s16(in16x8x4.val[2]); + int16x4_t in16x4_6 = vget_low_s16(in16x8x4.val[3]); + out32x4_0 = vmlal_lane_s16(out32x4_0, in16x4_0, coeff16x4, 3); + out32x4_0 = vmlal_lane_s16(out32x4_0, in16x4_2, coeff16x4, 2); + out32x4_0 = vmlal_lane_s16(out32x4_0, in16x4_4, coeff16x4, 1); + out32x4_0 = vmlal_lane_s16(out32x4_0, in16x4_6, coeff16x4, 0); + + // Mul and accumulate high 64-bit data. + // TODO: vget_high_s16 need extra cost on ARM64. This could be + // replaced by vmlal_high_lane_s16. But for the interface of + // vmlal_high_lane_s16, there is a bug in gcc 4.9. + // This issue need to be tracked in the future. + int16x4_t in16x4_1 = vget_high_s16(in16x8x4.val[0]); + int16x4_t in16x4_3 = vget_high_s16(in16x8x4.val[1]); + int16x4_t in16x4_5 = vget_high_s16(in16x8x4.val[2]); + int16x4_t in16x4_7 = vget_high_s16(in16x8x4.val[3]); + out32x4_1 = vmlal_lane_s16(out32x4_1, in16x4_1, coeff16x4, 3); + out32x4_1 = vmlal_lane_s16(out32x4_1, in16x4_3, coeff16x4, 2); + out32x4_1 = vmlal_lane_s16(out32x4_1, in16x4_5, coeff16x4, 1); + out32x4_1 = vmlal_lane_s16(out32x4_1, in16x4_7, coeff16x4, 0); + } + + for (; j < coefficients_length; j++) { + int16x4_t coeff16x4 = vld1_dup_s16(&coefficients[j]); + int16x8x4_t in16x8x4 = vld4q_s16(&data_in[i - j]); + + // Mul and accumulate low 64-bit data. + int16x4_t in16x4_0 = vget_low_s16(in16x8x4.val[0]); + out32x4_0 = vmlal_lane_s16(out32x4_0, in16x4_0, coeff16x4, 0); + + // Mul and accumulate high 64-bit data. + // TODO: vget_high_s16 need extra cost on ARM64. This could be + // replaced by vmlal_high_lane_s16. But for the interface of + // vmlal_high_lane_s16, there is a bug in gcc 4.9. + // This issue need to be tracked in the future. + int16x4_t in16x4_1 = vget_high_s16(in16x8x4.val[0]); + out32x4_1 = vmlal_lane_s16(out32x4_1, in16x4_1, coeff16x4, 0); + } + + // Saturate and store the output. + int16x4_t out16x4_0 = vqshrn_n_s32(out32x4_0, 12); + int16x4_t out16x4_1 = vqshrn_n_s32(out32x4_1, 12); + vst1q_s16(data_out, vcombine_s16(out16x4_0, out16x4_1)); + data_out += 8; + } + break; + } + default: { + for (i = delay; i < endpos1; i += factor * 8) { + // Round value, 0.5 in Q12. + int32x4_t out32x4_0 = vdupq_n_s32(2048); + int32x4_t out32x4_1 = vdupq_n_s32(2048); + + for (j = 0; j < coefficients_length; j++) { + int16x4_t coeff16x4 = vld1_dup_s16(&coefficients[j]); + int16x4_t in16x4_0 = vld1_dup_s16(&data_in[i - j]); + in16x4_0 = vld1_lane_s16(&data_in[i + factor - j], in16x4_0, 1); + in16x4_0 = vld1_lane_s16(&data_in[i + factor * 2 - j], in16x4_0, 2); + in16x4_0 = vld1_lane_s16(&data_in[i + factor * 3 - j], in16x4_0, 3); + int16x4_t in16x4_1 = vld1_dup_s16(&data_in[i + factor * 4 - j]); + in16x4_1 = vld1_lane_s16(&data_in[i + factor * 5 - j], in16x4_1, 1); + in16x4_1 = vld1_lane_s16(&data_in[i + factor * 6 - j], in16x4_1, 2); + in16x4_1 = vld1_lane_s16(&data_in[i + factor * 7 - j], in16x4_1, 3); + + // Mul and accumulate. + out32x4_0 = vmlal_lane_s16(out32x4_0, in16x4_0, coeff16x4, 0); + out32x4_1 = vmlal_lane_s16(out32x4_1, in16x4_1, coeff16x4, 0); + } + + // Saturate and store the output. + int16x4_t out16x4_0 = vqshrn_n_s32(out32x4_0, 12); + int16x4_t out16x4_1 = vqshrn_n_s32(out32x4_1, 12); + vst1q_s16(data_out, vcombine_s16(out16x4_0, out16x4_1)); + data_out += 8; + } + break; + } + } + + // Second part, do the rest iterations (if any). + for (; i < endpos; i += factor) { + out_s32 = 2048; // Round value, 0.5 in Q12. + + for (j = 0; j < coefficients_length; j++) { + out_s32 = WebRtc_MulAccumW16(coefficients[j], data_in[i - j], out_s32); + } + + // Saturate and store the output. + out_s32 >>= 12; + *data_out++ = WebRtcSpl_SatW32ToW16(out_s32); + } + + return 0; +} |