dsp_dotp_sqr.h64

来自「dm642函数库」· H64 代码 · 共 124 行

;* ======================================================================== *;
;*  TEXAS INSTRUMENTS, INC.                                                 *;
;*                                                                          *;
;*  DSPLIB  DSP Signal Processing Library                                   *;
;*                                                                          *;
;*      Release:        Revision 1.04b                                      *;
;*      CVS Revision:   1.10    Sun Sep 29 03:32:20 2002 (UTC)              *;
;*      Snapshot date:  23-Oct-2003                                         *;
;*                                                                          *;
;*  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) 2003 Texas Instruments, Incorporated.             *;
;*                          All Rights Reserved.                            *;
;* ======================================================================== *;
;* ======================================================================== *;
;*  Assembler compatibility shim for assembling 4.30 and later code on      *;
;*  tools prior to 4.30.                                                    *;
;* ======================================================================== *;
;* ======================================================================== *;
;*  End of assembler compatibility shim.                                    *;
;* ======================================================================== *;
* ========================================================================= *
*                                                                           *
*    TEXAS INSTRUMENTS, INC.                                                *
*                                                                           *
*   NAME                                                                    *
*       DSP_dotp_sqr                                                        *
*                                                                           *
*   REVISION DATE                                                           *
*       29-Mar-2002                                                         *
*                                                                           *
*   USAGE                                                                   *
*       This routine is C callable, and can be called as:                   *
*                                                                           *
*           int DSP_dotp_sqr                                                *
*           (                                                               *
*               int G,            /* Sum-of-y-squared initial value */      *
*               const short  *x,  /* First input array.             */      *
*               const short  *y,  /* Second input array.            */      *
*               int *restrict r,  /* Accumulation of x[] * y[].     */      *
*               int nx            /* Length of the input vector.    */      *
*           );                                                              *
*                                                                           *
*   DESCRIPTION                                                             *
*       This routine computes the dot product of x[] and y[] arrays,        *
*       adding it to the value in the location pointed to by 'd'.           *
*                                                                           *
*       Additionally, it computes the sum of the squares of the terms       *
*       in the y[] array, adding it to the argument G.  The final value     *
*       of G is given as the return value of the function.  This value      *
*       is used by the VSELP vocoder.                                       *
*                                                                           *
*       The following C code is an implementation of the algorithm          *
*       without restrictions.  Optimized implementations may add            *
*       restrictions as noted under the heading "ASSUMPTIONS."              *
*                                                                           *
*       int DSP_dotp_sqr                                                    *
*       (                                                                   *
*           int G,            /* Sum-of-y-squared initial value */          *
*           const short  *x,  /* First input array.             */          *
*           const short  *y,  /* Second input array.            */          *
*           int *restrict r,  /* Accumulation of x[] * y[].     */          *
*           int nx            /* Length of the input vector.    */          *
*       )                                                                   *
*       {                                                                   *
*           int i;                                                          *
*                                                                           *
*           for (i = 0; i < nx; i++)                                        *
*           {                                                               *
*               *r += x[i] * y[i];                                          *
*               G  += y[i] * y[i];                                          *
*           }                                                               *
*                                                                           *
*           return G;                                                       *
*       }                                                                   *
*                                                                           *
*   ASSUMPTIONS                                                             *
*       nx >= 12, nx % 4 == 0.                                              *
*                                                                           *
*   TECHNIQUES                                                              *
*       Unrolled 4 times to maximize multiplier utilization.                *
*                                                                           *
*   NOTES                                                                   *
*       This function is interrupt tolerant, but not interruptible.         *
*       It locks out interrupts for its entire duration.                    *
*                                                                           *
*   MEMORY NOTE                                                             *
*       Non-aligned accesses are used, so there are no alignment            *
*       constraints.  Also, as a result, no bank conflicts should occur.    *
*       This code is ENDIAN NEUTRAL.                                        *
*                                                                           *
*   CYCLES                                                                  *
*       cycles = nx/2 + 21.                                                 *
*       For nx == 16,  cycles == 29.                                        *
*       For nx == 100, cycles == 71.                                        *
*                                                                           *
*   CODESIZE                                                                *
*       152 bytes.                                                          *
*                                                                           *
*   SOURCE                                                                  *
*       DSPLIB.                                                             *
*                                                                           *
* ------------------------------------------------------------------------- *
*             Copyright (c) 2003 Texas Instruments, Incorporated.           *
*                            All Rights Reserved.                           *
* ========================================================================= *

        .global _DSP_dotp_sqr

* ========================================================================= *
*   End of file:  dsp_dotp_sqr.h64                                          *
* ------------------------------------------------------------------------- *
*             Copyright (c) 2003 Texas Instruments, Incorporated.           *
*                            All Rights Reserved.                           *
* ========================================================================= *