diff options
Diffstat (limited to 'third_party/webrtc/src/webrtc/common_audio/signal_processing/filter_ar_fast_q12_armv7.S')
| -rw-r--r-- | third_party/webrtc/src/webrtc/common_audio/signal_processing/filter_ar_fast_q12_armv7.S | 218 |
1 files changed, 218 insertions, 0 deletions
diff --git a/third_party/webrtc/src/webrtc/common_audio/signal_processing/filter_ar_fast_q12_armv7.S b/third_party/webrtc/src/webrtc/common_audio/signal_processing/filter_ar_fast_q12_armv7.S new file mode 100644 index 00000000..76c8eee7 --- /dev/null +++ b/third_party/webrtc/src/webrtc/common_audio/signal_processing/filter_ar_fast_q12_armv7.S @@ -0,0 +1,218 @@ +@ +@ Copyright (c) 2012 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. +@ + +@ This file contains the function WebRtcSpl_FilterARFastQ12(), optimized for +@ ARMv7 platform. The description header can be found in +@ signal_processing_library.h +@ +@ Output is bit-exact with the generic C code as in filter_ar_fast_q12.c, and +@ the reference C code at end of this file. + +@ Assumptions: +@ (1) data_length > 0 +@ (2) coefficients_length > 1 + +@ Register usage: +@ +@ r0: &data_in[i] +@ r1: &data_out[i], for result ouput +@ r2: &coefficients[0] +@ r3: coefficients_length +@ r4: Iteration counter for the outer loop. +@ r5: data_out[j] as multiplication inputs +@ r6: Calculated value for output data_out[]; interation counter for inner loop +@ r7: Partial sum of a filtering multiplication results +@ r8: Partial sum of a filtering multiplication results +@ r9: &data_out[], for filtering input; data_in[i] +@ r10: coefficients[j] +@ r11: Scratch +@ r12: &coefficients[j] + +#include "webrtc/system_wrappers/interface/asm_defines.h" + +GLOBAL_FUNCTION WebRtcSpl_FilterARFastQ12 +.align 2 +DEFINE_FUNCTION WebRtcSpl_FilterARFastQ12 + push {r4-r11} + + ldrsh r12, [sp, #32] @ data_length + subs r4, r12, #1 + beq ODD_LENGTH @ jump if data_length == 1 + +LOOP_LENGTH: + add r12, r2, r3, lsl #1 + sub r12, #4 @ &coefficients[coefficients_length - 2] + sub r9, r1, r3, lsl #1 + add r9, #2 @ &data_out[i - coefficients_length + 1] + ldr r5, [r9], #4 @ data_out[i - coefficients_length + {1,2}] + + mov r7, #0 @ sum1 + mov r8, #0 @ sum2 + subs r6, r3, #3 @ Iteration counter for inner loop. + beq ODD_A_LENGTH @ branch if coefficients_length == 3 + blt POST_LOOP_A_LENGTH @ branch if coefficients_length == 2 + +LOOP_A_LENGTH: + ldr r10, [r12], #-4 @ coefficients[j - 1], coefficients[j] + subs r6, #2 + smlatt r8, r10, r5, r8 @ sum2 += coefficients[j] * data_out[i - j + 1]; + smlatb r7, r10, r5, r7 @ sum1 += coefficients[j] * data_out[i - j]; + smlabt r7, r10, r5, r7 @ coefficients[j - 1] * data_out[i - j + 1]; + ldr r5, [r9], #4 @ data_out[i - j + 2], data_out[i - j + 3] + smlabb r8, r10, r5, r8 @ coefficients[j - 1] * data_out[i - j + 2]; + bgt LOOP_A_LENGTH + blt POST_LOOP_A_LENGTH + +ODD_A_LENGTH: + ldrsh r10, [r12, #2] @ Filter coefficients coefficients[2] + sub r12, #2 @ &coefficients[0] + smlabb r7, r10, r5, r7 @ sum1 += coefficients[2] * data_out[i - 2]; + smlabt r8, r10, r5, r8 @ sum2 += coefficients[2] * data_out[i - 1]; + ldr r5, [r9, #-2] @ data_out[i - 1], data_out[i] + +POST_LOOP_A_LENGTH: + ldr r10, [r12] @ coefficients[0], coefficients[1] + smlatb r7, r10, r5, r7 @ sum1 += coefficients[1] * data_out[i - 1]; + + ldr r9, [r0], #4 @ data_in[i], data_in[i + 1] + smulbb r6, r10, r9 @ output1 = coefficients[0] * data_in[i]; + sub r6, r7 @ output1 -= sum1; + + sbfx r11, r6, #12, #16 + ssat r7, #16, r6, asr #12 + cmp r7, r11 + addeq r6, r6, #2048 + ssat r6, #16, r6, asr #12 + strh r6, [r1], #2 @ Store data_out[i] + + smlatb r8, r10, r6, r8 @ sum2 += coefficients[1] * data_out[i]; + smulbt r6, r10, r9 @ output2 = coefficients[0] * data_in[i + 1]; + sub r6, r8 @ output1 -= sum1; + + sbfx r11, r6, #12, #16 + ssat r7, #16, r6, asr #12 + cmp r7, r11 + addeq r6, r6, #2048 + ssat r6, #16, r6, asr #12 + strh r6, [r1], #2 @ Store data_out[i + 1] + + subs r4, #2 + bgt LOOP_LENGTH + blt END @ For even data_length, it's done. Jump to END. + +@ Process i = data_length -1, for the case of an odd length. +ODD_LENGTH: + add r12, r2, r3, lsl #1 + sub r12, #4 @ &coefficients[coefficients_length - 2] + sub r9, r1, r3, lsl #1 + add r9, #2 @ &data_out[i - coefficients_length + 1] + mov r7, #0 @ sum1 + mov r8, #0 @ sum1 + subs r6, r3, #2 @ inner loop counter + beq EVEN_A_LENGTH @ branch if coefficients_length == 2 + +LOOP2_A_LENGTH: + ldr r10, [r12], #-4 @ coefficients[j - 1], coefficients[j] + ldr r5, [r9], #4 @ data_out[i - j], data_out[i - j + 1] + subs r6, #2 + smlatb r7, r10, r5, r7 @ sum1 += coefficients[j] * data_out[i - j]; + smlabt r8, r10, r5, r8 @ coefficients[j - 1] * data_out[i - j + 1]; + bgt LOOP2_A_LENGTH + addlt r12, #2 + blt POST_LOOP2_A_LENGTH + +EVEN_A_LENGTH: + ldrsh r10, [r12, #2] @ Filter coefficients coefficients[1] + ldrsh r5, [r9] @ data_out[i - 1] + smlabb r7, r10, r5, r7 @ sum1 += coefficients[1] * data_out[i - 1]; + +POST_LOOP2_A_LENGTH: + ldrsh r10, [r12] @ Filter coefficients coefficients[0] + ldrsh r9, [r0] @ data_in[i] + smulbb r6, r10, r9 @ output1 = coefficients[0] * data_in[i]; + sub r6, r7 @ output1 -= sum1; + sub r6, r8 @ output1 -= sum1; + sbfx r8, r6, #12, #16 + ssat r7, #16, r6, asr #12 + cmp r7, r8 + addeq r6, r6, #2048 + ssat r6, #16, r6, asr #12 + strh r6, [r1] @ Store the data_out[i] + +END: + pop {r4-r11} + bx lr + +@Reference C code: +@ +@void WebRtcSpl_FilterARFastQ12(int16_t* data_in, +@ int16_t* data_out, +@ int16_t* __restrict coefficients, +@ size_t coefficients_length, +@ size_t data_length) { +@ size_t i = 0; +@ size_t j = 0; +@ +@ assert(data_length > 0); +@ assert(coefficients_length > 1); +@ +@ for (i = 0; i < data_length - 1; i += 2) { +@ int32_t output1 = 0; +@ int32_t sum1 = 0; +@ int32_t output2 = 0; +@ int32_t sum2 = 0; +@ +@ for (j = coefficients_length - 1; j > 2; j -= 2) { +@ sum1 += coefficients[j] * data_out[i - j]; +@ sum1 += coefficients[j - 1] * data_out[i - j + 1]; +@ sum2 += coefficients[j] * data_out[i - j + 1]; +@ sum2 += coefficients[j - 1] * data_out[i - j + 2]; +@ } +@ +@ if (j == 2) { +@ sum1 += coefficients[2] * data_out[i - 2]; +@ sum2 += coefficients[2] * data_out[i - 1]; +@ } +@ +@ sum1 += coefficients[1] * data_out[i - 1]; +@ output1 = coefficients[0] * data_in[i]; +@ output1 -= sum1; +@ // Saturate and store the output. +@ output1 = WEBRTC_SPL_SAT(134215679, output1, -134217728); +@ data_out[i] = (int16_t)((output1 + 2048) >> 12); +@ +@ sum2 += coefficients[1] * data_out[i]; +@ output2 = coefficients[0] * data_in[i + 1]; +@ output2 -= sum2; +@ // Saturate and store the output. +@ output2 = WEBRTC_SPL_SAT(134215679, output2, -134217728); +@ data_out[i + 1] = (int16_t)((output2 + 2048) >> 12); +@ } +@ +@ if (i == data_length - 1) { +@ int32_t output1 = 0; +@ int32_t sum1 = 0; +@ +@ for (j = coefficients_length - 1; j > 1; j -= 2) { +@ sum1 += coefficients[j] * data_out[i - j]; +@ sum1 += coefficients[j - 1] * data_out[i - j + 1]; +@ } +@ +@ if (j == 1) { +@ sum1 += coefficients[1] * data_out[i - 1]; +@ } +@ +@ output1 = coefficients[0] * data_in[i]; +@ output1 -= sum1; +@ // Saturate and store the output. +@ output1 = WEBRTC_SPL_SAT(134215679, output1, -134217728); +@ data_out[i] = (int16_t)((output1 + 2048) >> 12); +@ } +@} |