energy_new.asm

来自「基于TMS320F2812的AMR+RS编解码+OFDM调制解调源程序。是sta」· 汇编 代码 · 共 60 行

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** Description:     energy_new() in agc.c                                  **
**                                                                         **
** Inputs                                                                  **
**                                                                         **
**   xar3---Word16 in[]                                                    **
**                                                                         **
** Outputs:                                                                **
**                                                                         ** 
**                                                                         **
** Return value :       acc                                                **
**                                                                         **
** Attribute    :       Cycles:834      Pm: 16                             **
**                      Modified Registers:  xar2,3,7                      **
**                                                                         **
** Programmer   :       Qi Ying                                            **
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            .global    _energy_new
            .ref       _energy_old 
_energy_new:
            movl   xar7,         xar3
            mov    T,            *xar7           ;in[0]
            mpy    P,     T,     *xar7++
            movb   acc,          #0 
            movb   xar2,         #38 
            SETC   OVM,SXM
_Loop_81:            
            mac    P,   *xar7++, *xar7++
            banz   _Loop_81,     ar2--
            addl   acc,          P<<pm           ;acc=s
            cmp    al,           #0xffff
            sb     _Line_93,     NEQ
            cmp    ah,           #0x7fff
            sb     _Line_93,     NEQ
            LCR    _energy_old
            LRETR
_Line_93:
            movb   ar7,         #4
            mov    T,           ar7
            asrl   acc,         T
            LRETR