dive.sa

DSP开发CCS里面FFT程序的线性汇编

        .global   _dive
_dive   .cproc    dataR,dataI
        .reg      i,k,l,n,p,x0,x1,x2,x3,x4,x5,x6,x7,xx
        .reg      xx0,xx1,xx2,xx3,xx4,xx5,xx6,xx7,xxt,xxk
        .reg      xa1,xa2,xa3,xa4,xa5,xa6,xa7,xa8
        .reg      cntr,cm,temp1,temp2,dr,di,drx,dix
        ZERO      i
        MVk       256,cntr
        MVk       128,xx0
        MVk       64,xx1
        MVk       32,xx2
        MVk       16,xx3
        MVK       8,xx4
        MVK       4,xx5
        MVK       2,xx6
        MVK       1,xx7
        
LOOP:   .trip     256,256,0
        
        MV        i,k
        MV        i,l
        MV        i,p
      ZERO      xxt
      ZERO      xxk
      AND       i,1,x7
      AND       i,2,x6
      AND       k,4,x5
      AND       k,8,x4
      AND       i,xx3,x3
      AND       i,xx2,x2
      AND       k,xx1,x1
      AND       k,xx0,x0
 [x7] ADD      xx0,xxt,xxt
 [x6] ADD      xx1,xxt,xxt
 [x5] ADD      xx2,xxt,xxt
 [x4] ADD      xx3,xxt,xxt
 [x3] ADD      xx4,xxk,xxk
 [x2] ADD      xx5,xxk,xxk
 [x1] ADD      xx6,xxk,xxk
 [x0] ADD      xx7,xxk,xxk
      ADD      xxt,xxk,xx
      CMPLT     l,xx,cm
  [cm]  LDW   .D1    *+dataR[l],dr
  [cm]  LDW   .D2    *+dataI[l],di
  [cm]  LDW   .D1    *+dataR[xx],drx
  [cm]  LDW   .D2    *+dataI[xx],dix
  [cm]  MV        dr,temp1
  [cm]  MV        di,temp2
  [cm]  STW   .D1    drx,*+dataR[l]
  [cm]  STW   .D2    dix,*+dataI[l]
  [cm]  STW   .D1    temp1,*+dataR[xx]
  [cm]  STW   .D2    temp2,*+dataI[xx]
        ADD         i,1,i
  [cntr]      SUB       cntr,1,cntr
       
  [cntr]  B        LOOP      
        .endproc