;* ======================================================================== *;
;* TEXAS INSTRUMENTS, INC. *;
;* *;
;* DSPLIB DSP Signal Processing Library *;
;* *;
;* Release: Version 1.02 *;
;* CVS Revision: 1.4 Fri Mar 29 21:10:31 2002 (UTC) *;
;* Snapshot date: 18-Apr-2002 *;
;* *;
;* This library contains proprietary intellectual property of Texas *;
;* Instruments, Inc. The library and its source code are protected by *;
;* various copyrights, and portions may also be protected by patents or *;
;* other legal protections. *;
;* *;
;* This software is licensed for use with Texas Instruments TMS320 *;
;* family DSPs. This license was provided to you prior to installing *;
;* the software. You may review this license by consulting the file *;
;* TI_license.PDF which accompanies the files in this library. *;
;* ------------------------------------------------------------------------ *;
;* Copyright (C) 2002 Texas Instruments, Incorporated. *;
;* All Rights Reserved. *;
;* ======================================================================== *;
* ========================================================================= *
* TEXAS INSTRUMENTS, INC. *
* *
* NAME *
* DSP_w_vec: Weighted vector sum *
* *
* *
* REVISION DATE *
* 29-Mar-2002 *
* *
* USAGE *
* This routine is C-callable and can be called as: *
* *
* void DSP_w_vec *
* ( *
* const short *x, /* Vector being weighted */ *
* const short *y, /* Non-weighted vector */ *
* short m, /* weighting factor */ *
* short *restrict r, /* Result vector */ *
* int nr /* Number of samples. */ *
* ); *
* *
* DESCRIPTION *
* The benchmark performs a weighted vector sum. The elements *
* of the x[] vector are weighted according to the Q15 value 'm', *
* and then added to the corresponding elements of the y[] vector. *
* The results are written to the r[] vector. *
* *
* C CODE *
* The following is a C code description of the algorithm. This *
* implementation may have restrictions, as noted under *
* "ASSUMPTIONS" below. *
* *
* void DSP_w_vec *
* ( *
* const short *x, /* Vector being weighted */ *
* const short *y, /* Non-weighted vector */ *
* short m, /* weighting factor */ *
* short *restrict r, /* Result vector */ *
* int nr /* Number of samples. */ *
* ) *
* { *
* int i; *
* *
* for (i = 0; i < nr; i++) *
* r[i] = ((m * x[i]) >> 15) + y[i]; *
* } *
* *
* ASSUMPTIONS *
* m is not -32768. *
* nr >= 4, nr is multiple of four. *
* Input and output arrays must be word aligned. *
* *
* MEMORY NOTE *
* No bank conflicts occur. *
* This code is endian neutral. *
* *
* TECHNIQUES *
* This loop is unrolled 4x to make full use of the available *
* memory bandwidth. *
* *
* SMPY is used in conjunction with shifts and masks so that the *
* m * x[i] terms may be packed pairs within 32-bit registers. This *
* allows us to use packed-data processing for the rest of the *
* algorithm, thereby maximizing our load/store bandwidth. *
* *
* NOTES *
* This code is interrupt tolerant but not interruptible. *
* *
* CYCLES *
* 3*nr/4 + 19 *
* For nr = 256, cycles = 211. *
* For nr = 1000, cycles = 770. *
* *
* CODESIZE *
* 192 bytes *
* *
* SOURCE *
* DSPLIB. *
* ------------------------------------------------------------------------- *
* Copyright (c) 2002 Texas Instruments, Incorporated. *
* All Rights Reserved. *
* ========================================================================= *
.global _DSP_w_vec
* ========================================================================= *
* End of file: dsp_w_vec.h62 *
* ------------------------------------------------------------------------- *
* Copyright (c) 2002 Texas Instruments, Incorporated. *
* All Rights Reserved. *
* ========================================================================= *