To avoid data dependencies, this does the following unroll, which
requires one extra but probably free addition:
    coeff = (b * left_weight) >> decorr_shift;
    b += a;
    a -= coeff;
    b -= coeff;
    swap(a, b);
		
	
			
		
			
				
	
	
		
			36 lines
		
	
	
		
			1.3 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			36 lines
		
	
	
		
			1.3 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * This file is part of FFmpeg.
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|  *
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|  * FFmpeg is free software; you can redistribute it and/or
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|  * modify it under the terms of the GNU Lesser General Public
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|  * License as published by the Free Software Foundation; either
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|  * version 2.1 of the License, or (at your option) any later version.
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|  *
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|  * FFmpeg is distributed in the hope that it will be useful,
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|  * but WITHOUT ANY WARRANTY; without even the implied warranty of
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|  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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|  * Lesser General Public License for more details.
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|  *
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|  * You should have received a copy of the GNU Lesser General Public
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|  * License along with FFmpeg; if not, write to the Free Software
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|  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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|  */
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| 
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| #ifndef AVCODEC_ALACDSP_H
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| #define AVCODEC_ALACDSP_H
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| 
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| #include <stdint.h>
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| 
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| typedef struct ALACDSPContext {
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|     void (*decorrelate_stereo)(int32_t *buffer[2], int nb_samples,
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|                                int decorr_shift, int decorr_left_weight);
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|     void (*append_extra_bits[2])(int32_t *buffer[2], int32_t *extra_bits_buffer[2],
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|                                  int extra_bits, int channels, int nb_samples);
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| } ALACDSPContext;
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| 
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| void ff_alacdsp_init(ALACDSPContext *c);
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| void ff_alacdsp_init_riscv(ALACDSPContext *c);
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| void ff_alacdsp_init_x86(ALACDSPContext *c);
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| 
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| #endif /* AVCODEC_ALACDSP_H */
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