text: /* Copyright (C) 2005 Analog Devices */
  /**
     @file ltp_bfin.h
     @author Jean-Marc Valin
     @brief Long-Term Prediction functions (Blackfin version)
  */
  /*
     Redistribution and use in source and binary forms, with or without
     modification, are permitted provided that the following conditions
     are met:
     
     - Redistributions of source code must retain the above copyright
     notice, this list of conditions and the following disclaimer.
     
     - Redistributions in binary form must reproduce the above copyright
     notice, this list of conditions and the following disclaimer in the
     documentation and/or other materials provided with the distribution.
     
     - Neither the name of the Xiph.org Foundation nor the names of its
     contributors may be used to endorse or promote products derived from
     this software without specific prior written permission.
     
     THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
     ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
     LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
     A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR
     CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
     EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
     PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
     PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
     LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
     NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
     SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
  
  #include "bfin.h"
  
  #define OVERRIDE_INNER_PROD
  spx_word32_t inner_prod(const spx_word16_t *x, const spx_word16_t *y, int len)
  {
     spx_word32_t sum=0;
     __asm__ __volatile__ (
        "P0 = %3;\n\t"
        "P1 = %1;\n\t"
        "P2 = %2;\n\t"
        "I0 = P1;\n\t"
        "I1 = P2;\n\t"
        "L0 = 0;\n\t"
        "L1 = 0;\n\t"
        "A0 = 0;\n\t"
        "R0.L = W[I0++] || R1.L = W[I1++];\n\t"
        "LOOP inner%= LC0 = P0;\n\t"
        "LOOP_BEGIN inner%=;\n\t"
           "A0 += R0.L*R1.L (IS) || R0.L = W[I0++] || R1.L = W[I1++];\n\t"
        "LOOP_END inner%=;\n\t"
        "A0 += R0.L*R1.L (IS);\n\t"
        "A0 = A0 >>> 6;\n\t"
        "R0 = A0;\n\t"
        "%0 = R0;\n\t"
     : "=m" (sum)
     : "m" (x), "m" (y), "d" (len-1)
     : "P0", "P1", "P2", "R0", "R1", "A0", "I0", "I1", "L0", "L1", "R3", "ASTAT" BFIN_HWLOOP0_REGS
     );
     return sum;
  }
  
  #define OVERRIDE_PITCH_XCORR
  void pitch_xcorr(const spx_word16_t *_x, const spx_word16_t *_y, spx_word32_t *corr, int len, int nb_pitch, char *stack)
  {
     corr += nb_pitch - 1;
     __asm__ __volatile__ (
        "P2 = %0;\n\t"
        "I0 = P2;\n\t" /* x in I0 */
        "B0 = P2;\n\t" /* x in B0 */
        "R0 = %3;\n\t" /* len in R0 */
        "P3 = %3;\n\t"
        "P3 += -2;\n\t" /* len in R0 */
        "P4 = %4;\n\t" /* nb_pitch in R0 */
        "R1 = R0 << 1;\n\t" /* number of bytes in x */
        "L0 = R1;\n\t"
        "P0 = %1;\n\t"
  
        "P1 = %2;\n\t"
        "B1 = P1;\n\t"
        "L1 = 0;\n\t" /*Disable looping on I1*/
  
        "r0 = [I0++];\n\t"
        "LOOP pitch%= LC0 = P4 >> 1;\n\t"
        "LOOP_BEGIN pitch%=;\n\t"
           "I1 = P0;\n\t"
           "A1 = A0 = 0;\n\t"
           "R1 = [I1++];\n\t"
           "LOOP inner_prod%= LC1 = P3 >> 1;\n\t"
           "LOOP_BEGIN inner_prod%=;\n\t"
              "A1 += R0.L*R1.H, A0 += R0.L*R1.L (IS) || R1.L = W[I1++];\n\t"
              "A1 += R0.H*R1.L, A0 += R0.H*R1.H (IS) || R1.H = W[I1++] || R0 = [I0++];\n\t"
           "LOOP_END inner_prod%=;\n\t"
           "A1 += R0.L*R1.H, A0 += R0.L*R1.L (IS) || R1.L = W[I1++];\n\t"
           "A1 += R0.H*R1.L, A0 += R0.H*R1.H (IS) || R0 = [I0++];\n\t"
           "A0 = A0 >>> 6;\n\t"
           "A1 = A1 >>> 6;\n\t"
           "R2 = A0, R3 = A1;\n\t"
           "[P1--] = r2;\n\t"
           "[P1--] = r3;\n\t"
           "P0 += 4;\n\t"
        "LOOP_END pitch%=;\n\t"
        "L0 = 0;\n\t"
     : : "m" (_x), "m" (_y), "m" (corr), "m" (len), "m" (nb_pitch)
     : "A0", "A1", "P0", "P1", "P2", "P3", "P4", "R0", "R1", "R2", "R3", "I0", "I1", "L0", "L1", "B0", "B1", "memory",
       "ASTAT" BFIN_HWLOOP0_REGS BFIN_HWLOOP1_REGS
     );
  }
  
  #define OVERRIDE_COMPUTE_PITCH_ERROR
  static inline spx_word32_t compute_pitch_error(spx_word16_t *C, spx_word16_t *g, spx_word16_t pitch_control)
  {
     spx_word32_t sum;
     __asm__ __volatile__
           (
           "A0 = 0;\n\t"
           
           "R0 = W[%1++];\n\t"
           "R1.L = %2.L*%5.L (IS);\n\t"
           "A0 += R1.L*R0.L (IS) || R0 = W[%1++];\n\t"
           
           "R1.L = %3.L*%5.L (IS);\n\t"
           "A0 += R1.L*R0.L (IS) || R0 = W[%1++];\n\t"
           
           "R1.L = %4.L*%5.L (IS);\n\t"
           "A0 += R1.L*R0.L (IS) || R0 = W[%1++];\n\t"
           
           "R1.L = %2.L*%3.L (IS);\n\t"
           "A0 -= R1.L*R0.L (IS) || R0 = W[%1++];\n\t"
  
           "R1.L = %4.L*%3.L (IS);\n\t"
           "A0 -= R1.L*R0.L (IS) || R0 = W[%1++];\n\t"
           
           "R1.L = %4.L*%2.L (IS);\n\t"
           "A0 -= R1.L*R0.L (IS) || R0 = W[%1++];\n\t"
           
           "R1.L = %2.L*%2.L (IS);\n\t"
           "A0 -= R1.L*R0.L (IS) || R0 = W[%1++];\n\t"
  
           "R1.L = %3.L*%3.L (IS);\n\t"
           "A0 -= R1.L*R0.L (IS) || R0 = W[%1++];\n\t"
           
           "R1.L = %4.L*%4.L (IS);\n\t"
           "A0 -= R1.L*R0.L (IS);\n\t"
           
           "%0 = A0;\n\t"
     : "=&D" (sum), "=a" (C)
     : "d" (g[0]), "d" (g[1]), "d" (g[2]), "d" (pitch_control), "1" (C)
     : "R0", "R1", "R2", "A0", "ASTAT"
           );
     return sum;
  }
  
  #define OVERRIDE_OPEN_LOOP_NBEST_PITCH
  #ifdef OVERRIDE_OPEN_LOOP_NBEST_PITCH
  void open_loop_nbest_pitch(spx_word16_t *sw, int start, int end, int len, int *pitch, spx_word16_t *gain, int N, char *stack)
  {
     int i,j,k;
     VARDECL(spx_word32_t *best_score);
     VARDECL(spx_word32_t *best_ener);
     spx_word32_t e0;
     VARDECL(spx_word32_t *corr);
     VARDECL(spx_word32_t *energy);
  
     ALLOC(best_score, N, spx_word32_t);
     ALLOC(best_ener, N, spx_word32_t);
     ALLOC(corr, end-start+1, spx_word32_t);
     ALLOC(energy, end-start+2, spx_word32_t);
  
     for (i=0;i<N;i++)
     {
          best_score[i]=-1;
          best_ener[i]=0;
          pitch[i]=start;
     }
  
     energy[0]=inner_prod(sw-start, sw-start, len);
     e0=inner_prod(sw, sw, len);
  
     /* energy update -------------------------------------*/
  
        __asm__ __volatile__
        (
  "        P0 = %0;\n\t"
  "        I1 = %1;\n\t"
  "        L1 = 0;\n\t"
  "        I2 = %2;\n\t"
  "        L2 = 0;\n\t"
  "        R2 = [P0++];\n\t"
  "        R3 = 0;\n\t"
  "        LSETUP (eu1, eu2) LC1 = %3;\n\t"
  "eu1:      R1.L = W [I1--] || R0.L = W [I2--] ;\n\t"
  "          R1 = R1.L * R1.L (IS);\n\t"
  "          R0 = R0.L * R0.L (IS);\n\t"
  "          R1 >>>= 6;\n\t"
  "          R1 = R1 + R2;\n\t"
  "          R0 >>>= 6;\n\t"
  "          R1 = R1 - R0;\n\t"
  "          R2 = MAX(R1,R3);\n\t"
  "eu2:      [P0++] = R2;\n\t"
         : : "d" (energy), "d" (&sw[-start-1]), "d" (&sw[-start+len-1]),
             "a" (end-start)  
         : "P0", "I1", "I2", "R0", "R1", "R2", "R3", "ASTAT" BFIN_HWLOOP1_REGS
         );
  
     pitch_xcorr(sw, sw-end, corr, len, end-start+1, stack);
  
     /* FIXME: Fixed-point and floating-point code should be merged */
     {
        VARDECL(spx_word16_t *corr16);
        VARDECL(spx_word16_t *ener16);
        ALLOC(corr16, end-start+1, spx_word16_t);
        ALLOC(ener16, end-start+1, spx_word16_t);
        /* Normalize to 180 so we can square it and it still fits in 16 bits */
        normalize16(corr, corr16, 180, end-start+1);
        normalize16(energy, ener16, 180, end-start+1);
  
        if (N == 1) {
  	/* optimised asm to handle N==1 case */
        __asm__ __volatile__
        (
  "        I0 = %1;\n\t"                     /* I0: corr16[]    */
  "        L0 = 0;\n\t"
  "        I1 = %2;\n\t"                     /* I1: energy      */
  "        L1 = 0;\n\t"
  "        R2 = -1;\n\t"                     /* R2: best score  */
  "        R3 = 0;\n\t"                      /* R3: best energy */
  "        P0 = %4;\n\t"                     /* P0: best pitch  */
  "        P1 = %4;\n\t"                     /* P1: counter     */
  "        LSETUP (sl1, sl2) LC1 = %3;\n\t"
  "sl1:      R0.L = W [I0++] || R1.L = W [I1++];\n\t"         
  "          R0 = R0.L * R0.L (IS);\n\t"
  "          R1   += 1;\n\t"
  "          R4   = R0.L * R3.L;\n\t"
  "          R5   = R2.L * R1.L;\n\t"
  "          cc   = R5 < R4;\n\t"
  "          if cc R2 = R0;\n\t"
  "          if cc R3 = R1;\n\t"
  "          if cc P0 = P1;\n\t"
  "sl2:      P1 += 1;\n\t"
  "        %0 = P0;\n\t"
         : "=&d" (pitch[0])
         : "a" (corr16), "a" (ener16), "a" (end+1-start), "d" (start) 
         : "P0", "P1", "I0", "I1", "R0", "R1", "R2", "R3", "R4", "R5",
           "ASTAT", "CC" BFIN_HWLOOP1_REGS
         );
  
        }
        else {
  	for (i=start;i<=end;i++)
  	  {
  	    spx_word16_t tmp = MULT16_16_16(corr16[i-start],corr16[i-start]);
  	    /* Instead of dividing the tmp by the energy, we multiply on the other side */
  	    if (MULT16_16(tmp,best_ener[N-1])>MULT16_16(best_score[N-1],ADD16(1,ener16[i-start])))
  	      {
  		/* We can safely put it last and then check */
  		best_score[N-1]=tmp;
  		best_ener[N-1]=ener16[i-start]+1;
  		pitch[N-1]=i;
  		/* Check if it comes in front of others */
  		for (j=0;j<N-1;j++)
  		  {
  		    if (MULT16_16(tmp,best_ener[j])>MULT16_16(best_score[j],ADD16(1,ener16[i-start])))
  		      {
  			for (k=N-1;k>j;k--)
  			  {
  			    best_score[k]=best_score[k-1];
  			    best_ener[k]=best_ener[k-1];
  			    pitch[k]=pitch[k-1];
  			  }
  			best_score[j]=tmp;
  			best_ener[j]=ener16[i-start]+1;
  			pitch[j]=i;
  			break;
  		      }
  		  }
  	      }
  	  }
        }
     }
  
     /* Compute open-loop gain */
     if (gain)
     {
         for (j=0;j<N;j++)
         {
            spx_word16_t g;
            i=pitch[j];
            g = DIV32(corr[i-start], 10+SHR32(MULT16_16(spx_sqrt(e0),spx_sqrt(energy[i-start])),6));
            /* FIXME: g = max(g,corr/energy) */
                     if (g<0)
                     g = 0;
               gain[j]=g;
         }
     }
  }
  #endif
  
  #define OVERRIDE_PITCH_GAIN_SEARCH_3TAP_VQ
  #ifdef OVERRIDE_PITCH_GAIN_SEARCH_3TAP_VQ
  static int pitch_gain_search_3tap_vq(
    const signed char *gain_cdbk,
    int                gain_cdbk_size,
    spx_word16_t      *C16,
    spx_word16_t       max_gain
  )
  {
    const signed char *ptr=gain_cdbk;
    int                best_cdbk=0;
    spx_word32_t       best_sum=-VERY_LARGE32;
    spx_word32_t       sum=0;
    spx_word16_t       g[3];
    spx_word16_t       pitch_control=64;
    spx_word16_t       gain_sum;
    int                i;
  
        /* fast asm version of VQ codebook search */
  
        __asm__ __volatile__
        (
  
  "        P0 = %2;\n\t"                     /* P0: ptr to gain_cdbk */
  "        L1 = 0;\n\t"                      /* no circ addr for L1  */
  "        %0 = 0;\n\t"                      /* %0: best_sum         */
  "        %1 = 0;\n\t"                      /* %1: best_cbdk        */
  "        P1 = 0;\n\t"                      /* P1: loop counter     */
  
  "        LSETUP (pgs1, pgs2) LC1 = %4;\n\t"
  "pgs1:     R2  = B [P0++] (X);\n\t"        /* R2: g[0]             */
  "          R3  = B [P0++] (X);\n\t"        /* R3: g[1]             */
  "          R4  = B [P0++] (X);\n\t"        /* R4: g[2]             */
  "          R2 += 32;\n\t"
  "          R3 += 32;\n\t"
  "          R4 += 32;\n\t"
  "          R4.H = 64;\n\t"                 /* R4.H: pitch_control    */
  
  "          R0  = B [P0++] (X);\n\t"              
  "          B0  = R0;\n\t"                  /* BO: gain_sum         */
            
             /* compute_pitch_error() -------------------------------*/
  
  "          I1 = %3;\n\t"                   /* I1: ptr to C         */
  "          A0 = 0;\n\t"
           
  "          R0.L = W[I1++];\n\t"
  "          R1.L = R2.L*R4.H (IS);\n\t"
  "          A0 += R1.L*R0.L (IS) || R0.L = W[I1++];\n\t"
           
  "          R1.L = R3.L*R4.H (IS);\n\t"
  "          A0 += R1.L*R0.L (IS) || R0.L = W[I1++];\n\t"
           
  "          R1.L = R4.L*R4.H (IS);\n\t"
  "          A0 += R1.L*R0.L (IS) || R0.L = W[I1++];\n\t"
           
  "          R1.L = R2.L*R3.L (IS);\n\t"
  "          A0 -= R1.L*R0.L (IS) || R0.L = W[I1++];\n\t"
  
  "          R1.L = R4.L*R3.L (IS);\n\t"
  "          A0 -= R1.L*R0.L (IS) || R0.L = W[I1++];\n\t"
           
  "          R1.L = R4.L*R2.L (IS);\n\t"
  "          A0 -= R1.L*R0.L (IS) || R0.L = W[I1++];\n\t"
           
  "          R1.L = R2.L*R2.L (IS);\n\t"
  "          A0 -= R1.L*R0.L (IS) || R0.L = W[I1++];\n\t"
  
  "          R1.L = R3.L*R3.L (IS);\n\t"
  "          A0 -= R1.L*R0.L (IS) || R0.L = W[I1++];\n\t"
           
  "          R1.L = R4.L*R4.L (IS);\n\t"
  "          R0 = (A0 -= R1.L*R0.L) (IS);\n\t"
  
  /*
      Re-arrange the if-then to code efficiently on the Blackfin:
  
        if (sum>best_sum && gain_sum<=max_gain)   ------ (1)
  
        if (sum>best_sum && !(gain_sum>max_gain)) ------ (2)
  
        if (max_gain<=gain_sum) {                 ------ (3)
        sum = -VERY_LARGE32;
        }
        if (best_sum<=sum)
  
      The blackin cc instructions are all of the form:
  
        cc = x < y (or cc = x <= y)
  */
  "          R1 = B0\n\t"
  "          R2 = %5\n\t"
  "          R3 = %6\n\t"
  "          cc = R2 <= R1;\n\t" 
  "          if cc R0 = R3;\n\t"
  "          cc = %0 <= R0;\n\t"
  "          if cc %0 = R0;\n\t"
  "          if cc %1 = P1;\n\t"
  
  "pgs2:     P1 += 1;\n\t"
     
         : "=&d" (best_sum), "=&d" (best_cdbk) 
         : "a" (gain_cdbk), "a" (C16), "a" (gain_cdbk_size), "a" (max_gain),
           "b" (-VERY_LARGE32)
         : "R0", "R1", "R2", "R3", "R4", "P0", 
           "P1", "I1", "L1", "A0", "B0", "CC", "ASTAT" BFIN_HWLOOP1_REGS
         );
  
    return best_cdbk;
  }
  #endif
  
  