/* * Copyright (c) 2014 RISC OS Open Ltd * Author: Ben Avison * * This file is part of Libav. * * Libav is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * Libav is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with Libav; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ #include "libavutil/arm/asm.S" #define MAX_CHANNELS 8 #define MAX_FIR_ORDER 8 #define MAX_IIR_ORDER 4 #define MAX_RATEFACTOR 4 #define MAX_BLOCKSIZE (40 * MAX_RATEFACTOR) PST .req a1 PCO .req a2 AC0 .req a3 AC1 .req a4 CO0 .req v1 CO1 .req v2 CO2 .req v3 CO3 .req v4 ST0 .req v5 ST1 .req v6 ST2 .req sl ST3 .req fp I .req ip PSAMP .req lr // Some macros that do loads/multiplies where the register number is determined // from an assembly-time expression. Boy is GNU assembler's syntax ugly... .macro load group, index, base, offset .altmacro load_ \group, %(\index), \base, \offset .noaltmacro .endm .macro load_ group, index, base, offset ldr \group\index, [\base, #\offset] .endm .macro loadd group, index, base, offset .altmacro loadd_ \group, %(\index), %(\index+1), \base, \offset .noaltmacro .endm .macro loadd_ group, index0, index1, base, offset A .if \offset >= 256 A ldr \group\index0, [\base, #\offset] A ldr \group\index1, [\base, #(\offset) + 4] A .else ldrd \group\index0, \group\index1, [\base, #\offset] A .endif .endm .macro multiply index, accumulate, long .altmacro multiply_ %(\index), \accumulate, \long .noaltmacro .endm .macro multiply_ index, accumulate, long .if \long .if \accumulate smlal AC0, AC1, CO\index, ST\index .else smull AC0, AC1, CO\index, ST\index .endif .else .if \accumulate mla AC0, CO\index, ST\index, AC0 .else mul AC0, CO\index, ST\index .endif .endif .endm // A macro to update the load register number and load offsets .macro inc howmany .set LOAD_REG, (LOAD_REG + \howmany) & 3 .set OFFSET_CO, OFFSET_CO + 4 * \howmany .set OFFSET_ST, OFFSET_ST + 4 * \howmany .if FIR_REMAIN > 0 .set FIR_REMAIN, FIR_REMAIN - \howmany .if FIR_REMAIN == 0 .set OFFSET_CO, 4 * MAX_FIR_ORDER .set OFFSET_ST, 4 * (MAX_BLOCKSIZE + MAX_FIR_ORDER) .endif .elseif IIR_REMAIN > 0 .set IIR_REMAIN, IIR_REMAIN - \howmany .endif .endm // Macro to implement the inner loop for one specific combination of parameters .macro implement_filter mask_minus1, shift_0, shift_8, iir_taps, fir_taps .set TOTAL_TAPS, \iir_taps + \fir_taps // Deal with register allocation... .set DEFINED_SHIFT, 0 .set DEFINED_MASK, 0 .set SHUFFLE_SHIFT, 0 .set SHUFFLE_MASK, 0 .set SPILL_SHIFT, 0 .set SPILL_MASK, 0 .if TOTAL_TAPS == 0 // Little register pressure in this case - just keep MASK where it was .if !\mask_minus1 MASK .req ST1 .set DEFINED_MASK, 1 .endif .else .if \shift_0 .if !\mask_minus1 // AC1 is unused with shift 0 MASK .req AC1 .set DEFINED_MASK, 1 .set SHUFFLE_MASK, 1 .endif .elseif \shift_8 .if !\mask_minus1 .if TOTAL_TAPS <= 4 // All coefficients are preloaded (so pointer not needed) MASK .req PCO .set DEFINED_MASK, 1 .set SHUFFLE_MASK, 1 .else .set SPILL_MASK, 1 .endif .endif .else // shift not 0 or 8 .if TOTAL_TAPS <= 3 // All coefficients are preloaded, and at least one CO register is unused .if \fir_taps & 1 SHIFT .req CO0 .set DEFINED_SHIFT, 1 .set SHUFFLE_SHIFT, 1 .else SHIFT .req CO3 .set DEFINED_SHIFT, 1 .set SHUFFLE_SHIFT, 1 .endif .if !\mask_minus1 MASK .req PCO .set DEFINED_MASK, 1 .set SHUFFLE_MASK, 1 .endif .elseif TOTAL_TAPS == 4 // All coefficients are preloaded SHIFT .req PCO .set DEFINED_SHIFT, 1 .set SHUFFLE_SHIFT, 1 .if !\mask_minus1 .set SPILL_MASK, 1 .endif .else .set SPILL_SHIFT, 1 .if !\mask_minus1 .set SPILL_MASK, 1 .endif .endif .endif .endif .if SPILL_SHIFT SHIFT .req ST0 .set DEFINED_SHIFT, 1 .endif .if SPILL_MASK MASK .req ST1 .set DEFINED_MASK, 1 .endif // Preload coefficients if possible .if TOTAL_TAPS <= 4 .set OFFSET_CO, 0 .if \fir_taps & 1 .set LOAD_REG, 1 .else .set LOAD_REG, 0 .endif .rept \fir_taps load CO, LOAD_REG, PCO, OFFSET_CO .set LOAD_REG, (LOAD_REG + 1) & 3 .set OFFSET_CO, OFFSET_CO + 4 .endr .set OFFSET_CO, 4 * MAX_FIR_ORDER .rept \iir_taps load CO, LOAD_REG, PCO, OFFSET_CO .set LOAD_REG, (LOAD_REG + 1) & 3 .set OFFSET_CO, OFFSET_CO + 4 .endr .endif // Move mask/shift to final positions if necessary // Need to do this after preloading, because in some cases we // reuse the coefficient pointer register .if SHUFFLE_SHIFT mov SHIFT, ST0 .endif .if SHUFFLE_MASK mov MASK, ST1 .endif // Begin loop 01: .if TOTAL_TAPS == 0 // Things simplify a lot in this case // In fact this could be pipelined further if it's worth it... ldr ST0, [PSAMP] subs I, I, #1 .if !\mask_minus1 and ST0, ST0, MASK .endif str ST0, [PST, #-4]! str ST0, [PST, #4 * (MAX_BLOCKSIZE + MAX_FIR_ORDER)] str ST0, [PSAMP], #4 * MAX_CHANNELS bne 01b .else .if \fir_taps & 1 .set LOAD_REG, 1 .else .set LOAD_REG, 0 .endif .set LOAD_BANK, 0 .set FIR_REMAIN, \fir_taps .set IIR_REMAIN, \iir_taps .if FIR_REMAIN == 0 // only IIR terms .set OFFSET_CO, 4 * MAX_FIR_ORDER .set OFFSET_ST, 4 * (MAX_BLOCKSIZE + MAX_FIR_ORDER) .else .set OFFSET_CO, 0 .set OFFSET_ST, 0 .endif .set MUL_REG, LOAD_REG .set COUNTER, 0 .rept TOTAL_TAPS + 2 // Do load(s) .if FIR_REMAIN != 0 || IIR_REMAIN != 0 .if COUNTER == 0 .if TOTAL_TAPS > 4 load CO, LOAD_REG, PCO, OFFSET_CO .endif load ST, LOAD_REG, PST, OFFSET_ST inc 1 .elseif COUNTER == 1 && (\fir_taps & 1) == 0 .if TOTAL_TAPS > 4 load CO, LOAD_REG, PCO, OFFSET_CO .endif load ST, LOAD_REG, PST, OFFSET_ST inc 1 .elseif LOAD_BANK == 0 .if TOTAL_TAPS > 4 .if FIR_REMAIN == 0 && IIR_REMAIN == 1 load CO, LOAD_REG, PCO, OFFSET_CO .else loadd CO, LOAD_REG, PCO, OFFSET_CO .endif .endif .set LOAD_BANK, 1 .else .if FIR_REMAIN == 0 && IIR_REMAIN == 1 load ST, LOAD_REG, PST, OFFSET_ST inc 1 .else loadd ST, LOAD_REG, PST, OFFSET_ST inc 2 .endif .set LOAD_BANK, 0 .endif .endif // Do interleaved multiplies, slightly delayed .if COUNTER >= 2 multiply MUL_REG, COUNTER > 2, !\shift_0 .set MUL_REG, (MUL_REG + 1) & 3 .endif .set COUNTER, COUNTER + 1 .endr // Post-process the result of the multiplies .if SPILL_SHIFT ldr SHIFT, [sp, #9*4 + 0*4] .endif .if SPILL_MASK ldr MASK, [sp, #9*4 + 1*4] .endif ldr ST2, [PSAMP] subs I, I, #1 .if \shift_8 mov AC0, AC0, lsr #8 orr AC0, AC0, AC1, lsl #24 .elseif !\shift_0 rsb ST3, SHIFT, #32 mov AC0, AC0, lsr SHIFT A orr AC0, AC0, AC1, lsl ST3 T mov AC1, AC1, lsl ST3 T orr AC0, AC0, AC1 .endif .if \mask_minus1 add ST3, ST2, AC0 .else add ST2, ST2, AC0 and ST3, ST2, MASK sub ST2, ST3, AC0 .endif str ST3, [PST, #-4]! str ST2, [PST, #4 * (MAX_BLOCKSIZE + MAX_FIR_ORDER)] str ST3, [PSAMP], #4 * MAX_CHANNELS bne 01b .endif b 99f .if DEFINED_SHIFT .unreq SHIFT .endif .if DEFINED_MASK .unreq MASK .endif .endm .macro switch_on_fir_taps mask_minus1, shift_0, shift_8, iir_taps A ldr pc, [pc, a3, LSL #2] // firorder is in range 0-(8-iir_taps) T tbh [pc, a3, lsl #1] 0: A .word 0, 70f, 71f, 72f, 73f, 74f T .hword (70f - 0b) / 2, (71f - 0b) / 2, (72f - 0b) / 2, (73f - 0b) / 2, (74f - 0b) / 2 .if \iir_taps <= 3 A .word 75f T .hword (75f - 0b) / 2 .if \iir_taps <= 2 A .word 76f T .hword (76f - 0b) / 2 .if \iir_taps <= 1 A .word 77f T .hword (77f - 0b) / 2 .if \iir_taps == 0 A .word 78f T .hword (78f - 0b) / 2 .endif .endif .endif .endif 70: implement_filter \mask_minus1, \shift_0, \shift_8, \iir_taps, 0 71: implement_filter \mask_minus1, \shift_0, \shift_8, \iir_taps, 1 72: implement_filter \mask_minus1, \shift_0, \shift_8, \iir_taps, 2 73: implement_filter \mask_minus1, \shift_0, \shift_8, \iir_taps, 3 74: implement_filter \mask_minus1, \shift_0, \shift_8, \iir_taps, 4 .if \iir_taps <= 3 75: implement_filter \mask_minus1, \shift_0, \shift_8, \iir_taps, 5 .if \iir_taps <= 2 76: implement_filter \mask_minus1, \shift_0, \shift_8, \iir_taps, 6 .if \iir_taps <= 1 77: implement_filter \mask_minus1, \shift_0, \shift_8, \iir_taps, 7 .if \iir_taps == 0 78: implement_filter \mask_minus1, \shift_0, \shift_8, \iir_taps, 8 .endif .endif .endif .endif .endm .macro switch_on_iir_taps mask_minus1, shift_0, shift_8 A ldr pc, [pc, a4, LSL #2] // irorder is in range 0-4 T tbh [pc, a4, lsl #1] 0: A .word 0, 60f, 61f, 62f, 63f, 64f T .hword (60f - 0b) / 2, (61f - 0b) / 2, (62f - 0b) / 2, (63f - 0b) / 2, (64f - 0b) / 2 60: switch_on_fir_taps \mask_minus1, \shift_0, \shift_8, 0 61: switch_on_fir_taps \mask_minus1, \shift_0, \shift_8, 1 62: switch_on_fir_taps \mask_minus1, \shift_0, \shift_8, 2 63: switch_on_fir_taps \mask_minus1, \shift_0, \shift_8, 3 64: switch_on_fir_taps \mask_minus1, \shift_0, \shift_8, 4 .endm /* void ff_mlp_filter_channel_arm(int32_t *state, const int32_t *coeff, * int firorder, int iirorder, * unsigned int filter_shift, int32_t mask, * int blocksize, int32_t *sample_buffer); */ function ff_mlp_filter_channel_arm, export=1 push {v1-fp,lr} add v1, sp, #9*4 // point at arguments on stack ldm v1, {ST0,ST1,I,PSAMP} cmp ST1, #-1 bne 30f movs ST2, ST0, lsl #29 // shift is in range 0-15; we want to special-case 0 and 8 bne 20f bcs 10f switch_on_iir_taps 1, 1, 0 10: switch_on_iir_taps 1, 0, 1 20: switch_on_iir_taps 1, 0, 0 30: movs ST2, ST0, lsl #29 // shift is in range 0-15; we want to special-case 0 and 8 bne 50f bcs 40f switch_on_iir_taps 0, 1, 0 40: switch_on_iir_taps 0, 0, 1 50: switch_on_iir_taps 0, 0, 0 99: pop {v1-fp,pc} endfunc .unreq PST .unreq PCO .unreq AC0 .unreq AC1 .unreq CO0 .unreq CO1 .unreq CO2 .unreq CO3 .unreq ST0 .unreq ST1 .unreq ST2 .unreq ST3 .unreq I .unreq PSAMP