dif8_8.dsp

来自「平台：ADSP21xx 编程语言：ASM 说明：ADSP21xx-离散余弦变」· DSP 代码 · 共 31 行

.module/ram do_DIF8_8;        {*** 1 8-way DIFs ***}
.external tmp;
.entry DIF8_8;

DIF8_8:
        i0=^tmp;
        i1=^tmp+4;
        m1=1;

        ax1=dm(i3,m3);
        af=pass ax1, ax0=dm(i2,m2);
        ar=ax0+af, ax1=dm(i3,m3), my0=pm(i6,m6);
        ar=ax0-af, dm(i0,m1)=ar;
        mr=ar*my0(ss);
        
        cntr=2;
        do d8x8 until ce;
                af=pass ax1, ax0=dm(i2,m2);
                ar=ax0+af, ax1=dm(i3,m3), my0=pm(i6,m6);
                ar=ax0-af, dm(i0,m1)=ar;
        d8x8:   mr=ar*my0(ss), dm(i1,m1)=mr1;
 
        af=pass ax1, ax0=dm(i2,m2);
        ar=ax0+af,                my0=pm(i6,m6);
        ar=ax0-af, dm(i0,m1)=ar;
        mr=ar*my0(ss), dm(i1,m1)=mr1;
        dm(i1,m1)=mr1;

        rts;                               {*** end 1 8-way DIFs ***}
.endmod;