diff options
Diffstat (limited to 'third_party/webrtc/src/webrtc/common_audio/signal_processing/complex_bit_reverse_arm.S')
| -rw-r--r-- | third_party/webrtc/src/webrtc/common_audio/signal_processing/complex_bit_reverse_arm.S | 119 |
1 files changed, 119 insertions, 0 deletions
diff --git a/third_party/webrtc/src/webrtc/common_audio/signal_processing/complex_bit_reverse_arm.S b/third_party/webrtc/src/webrtc/common_audio/signal_processing/complex_bit_reverse_arm.S new file mode 100644 index 00000000..e7f8a819 --- /dev/null +++ b/third_party/webrtc/src/webrtc/common_audio/signal_processing/complex_bit_reverse_arm.S @@ -0,0 +1,119 @@ +@ +@ 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_ComplexBitReverse(), optimized +@ for ARMv5 platforms. +@ Reference C code is in file complex_bit_reverse.c. Bit-exact. + +#include "webrtc/system_wrappers/interface/asm_defines.h" + +GLOBAL_FUNCTION WebRtcSpl_ComplexBitReverse +.align 2 +DEFINE_FUNCTION WebRtcSpl_ComplexBitReverse + push {r4-r7} + + cmp r1, #7 + adr r3, index_7 @ Table pointer. + mov r4, #112 @ Number of interations. + beq PRE_LOOP_STAGES_7_OR_8 + + cmp r1, #8 + adr r3, index_8 @ Table pointer. + mov r4, #240 @ Number of interations. + beq PRE_LOOP_STAGES_7_OR_8 + + mov r3, #1 @ Initialize m. + mov r1, r3, asl r1 @ n = 1 << stages; + subs r6, r1, #1 @ nn = n - 1; + ble END + + mov r5, r0 @ &complex_data + mov r4, #0 @ ml + +LOOP_GENERIC: + rsb r12, r4, r6 @ l > nn - mr + mov r2, r1 @ n + +LOOP_SHIFT: + asr r2, #1 @ l >>= 1; + cmp r2, r12 + bgt LOOP_SHIFT + + sub r12, r2, #1 + and r4, r12, r4 + add r4, r2 @ mr = (mr & (l - 1)) + l; + cmp r4, r3 @ mr <= m ? + ble UPDATE_REGISTERS + + mov r12, r4, asl #2 + ldr r7, [r5, #4] @ complex_data[2 * m, 2 * m + 1]. + @ Offset 4 due to m incrementing from 1. + ldr r2, [r0, r12] @ complex_data[2 * mr, 2 * mr + 1]. + str r7, [r0, r12] + str r2, [r5, #4] + +UPDATE_REGISTERS: + add r3, r3, #1 + add r5, #4 + cmp r3, r1 + bne LOOP_GENERIC + + b END + +PRE_LOOP_STAGES_7_OR_8: + add r4, r3, r4, asl #1 + +LOOP_STAGES_7_OR_8: + ldrsh r2, [r3], #2 @ index[m] + ldrsh r5, [r3], #2 @ index[m + 1] + ldr r1, [r0, r2] @ complex_data[index[m], index[m] + 1] + ldr r12, [r0, r5] @ complex_data[index[m + 1], index[m + 1] + 1] + cmp r3, r4 + str r1, [r0, r5] + str r12, [r0, r2] + bne LOOP_STAGES_7_OR_8 + +END: + pop {r4-r7} + bx lr + +@ The index tables. Note the values are doubles of the actual indexes for 16-bit +@ elements, different from the generic C code. It actually provides byte offsets +@ for the indexes. + +.align 2 +index_7: @ Indexes for stages == 7. + .short 4, 256, 8, 128, 12, 384, 16, 64, 20, 320, 24, 192, 28, 448, 36, 288 + .short 40, 160, 44, 416, 48, 96, 52, 352, 56, 224, 60, 480, 68, 272, 72, 144 + .short 76, 400, 84, 336, 88, 208, 92, 464, 100, 304, 104, 176, 108, 432, 116 + .short 368, 120, 240, 124, 496, 132, 264, 140, 392, 148, 328, 152, 200, 156 + .short 456, 164, 296, 172, 424, 180, 360, 184, 232, 188, 488, 196, 280, 204 + .short 408, 212, 344, 220, 472, 228, 312, 236, 440, 244, 376, 252, 504, 268 + .short 388, 276, 324, 284, 452, 300, 420, 308, 356, 316, 484, 332, 404, 348 + .short 468, 364, 436, 380, 500, 412, 460, 444, 492 + +index_8: @ Indexes for stages == 8. + .short 4, 512, 8, 256, 12, 768, 16, 128, 20, 640, 24, 384, 28, 896, 32, 64 + .short 36, 576, 40, 320, 44, 832, 48, 192, 52, 704, 56, 448, 60, 960, 68, 544 + .short 72, 288, 76, 800, 80, 160, 84, 672, 88, 416, 92, 928, 100, 608, 104 + .short 352, 108, 864, 112, 224, 116, 736, 120, 480, 124, 992, 132, 528, 136 + .short 272, 140, 784, 148, 656, 152, 400, 156, 912, 164, 592, 168, 336, 172 + .short 848, 176, 208, 180, 720, 184, 464, 188, 976, 196, 560, 200, 304, 204 + .short 816, 212, 688, 216, 432, 220, 944, 228, 624, 232, 368, 236, 880, 244 + .short 752, 248, 496, 252, 1008, 260, 520, 268, 776, 276, 648, 280, 392, 284 + .short 904, 292, 584, 296, 328, 300, 840, 308, 712, 312, 456, 316, 968, 324 + .short 552, 332, 808, 340, 680, 344, 424, 348, 936, 356, 616, 364, 872, 372 + .short 744, 376, 488, 380, 1000, 388, 536, 396, 792, 404, 664, 412, 920, 420 + .short 600, 428, 856, 436, 728, 440, 472, 444, 984, 452, 568, 460, 824, 468 + .short 696, 476, 952, 484, 632, 492, 888, 500, 760, 508, 1016, 524, 772, 532 + .short 644, 540, 900, 548, 580, 556, 836, 564, 708, 572, 964, 588, 804, 596 + .short 676, 604, 932, 620, 868, 628, 740, 636, 996, 652, 788, 668, 916, 684 + .short 852, 692, 724, 700, 980, 716, 820, 732, 948, 748, 884, 764, 1012, 796 + .short 908, 812, 844, 828, 972, 860, 940, 892, 1004, 956, 988 |