20030225-1.c

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/* PR target/9732
   This testcase segfaulted on PPC because PIC_OFFSET_TABLE_REGNUM was no
   fixed register.
   Distilled from the xvid sources by Guillaume Morin <[e-mail]>
   and Benjamin Herrenschmidt <[e-mail]>.  */
/* { dg-do run } */
/* { dg-options "-O2 -fPIC" } */
/* { dg-warning "not supported" "PIC unsupported" { target cris-*-elf* mmix-*-* } 0 } */


extern void exit (int);

#define W1 2841					/* 2048*sqrt(2)*cos(1*pi/16) */
#define W2 2676					/* 2048*sqrt(2)*cos(2*pi/16) */
#define W3 2408					/* 2048*sqrt(2)*cos(3*pi/16) */
#define W5 1609					/* 2048*sqrt(2)*cos(5*pi/16) */
#define W6 1108					/* 2048*sqrt(2)*cos(6*pi/16) */
#define W7 565					/* 2048*sqrt(2)*cos(7*pi/16) */


/* private data */
static short iclip[1024];		/* clipping table */
static short *iclp;

void
idct_int32(short *const block)
{
  static short *blk;
  static long i;
  static long X0, X1, X2, X3, X4, X5, X6, X7, X8;

  for (i = 0; i < 8; i++)		/* idct columns */
    {
      blk = block + i;
      /* shortcut  */
      if (! ((X1 = (blk[8 * 4] << 8)) | (X2 = blk[8 * 6])
	     | (X3 = blk[8 * 2]) | (X4 = blk[8 * 1]) | (X5 = blk[8 * 7])
	     | (X6 = blk[8 * 5]) | (X7 = blk[8 * 3])))
	{
	  blk[8 * 0] = blk[8 * 1] = blk[8 * 2] = 
	    blk[8 * 3] = blk[8 * 4] =
	    blk[8 * 5] = blk[8 * 6] = blk[8 * 7] =
	    iclp[(blk[8 * 0] + 32) >> 6];
	  continue;
	}
      X0 = (blk[8 * 0] << 8) + 8192;

      /* first stage  */
      X8 = W7 * (X4 + X5) + 4;
      X4 = (X8 + (W1 - W7) * X4) >> 3;
      X5 = (X8 - (W1 + W7) * X5) >> 3;
      X8 = W3 * (X6 + X7) + 4;
      X6 = (X8 - (W3 - W5) * X6) >> 3;
      X7 = (X8 - (W3 + W5) * X7) >> 3;

      /* second stage  */
      X8 = X0 + X1;
      X0 -= X1;
      X1 = W6 * (X3 + X2) + 4;
      X2 = (X1 - (W2 + W6) * X2) >> 3;
      X3 = (X1 + (W2 - W6) * X3) >> 3;
      X1 = X4 + X6;
      X4 -= X6;
      X6 = X5 + X7;
      X5 -= X7;

      /* third stage  */
      X7 = X8 + X3;
      X8 -= X3;
      X3 = X0 + X2;
      X0 -= X2;
      X2 = (181 * (X4 + X5) + 128) >> 8;
      X4 = (181 * (X4 - X5) + 128) >> 8;

      /* fourth stage  */
      blk[8 * 0] = iclp[(X7 + X1) >> 14];
      blk[8 * 1] = iclp[(X3 + X2) >> 14];
      blk[8 * 2] = iclp[(X0 + X4) >> 14];
      blk[8 * 3] = iclp[(X8 + X6) >> 14];
      blk[8 * 4] = iclp[(X8 - X6) >> 14];
      blk[8 * 5] = iclp[(X0 - X4) >> 14];
      blk[8 * 6] = iclp[(X3 - X2) >> 14];
      blk[8 * 7] = iclp[(X7 - X1) >> 14];
    }
}								/* end function idct_int32(block) */


int main(void) {
  int i;
  unsigned short tab[64];

  for (i = 0 ; i < 64 ; ++i) 
    {  
      tab[i] = (1+(int) (65535)*8000/(2147483647+1.0));
    }
  
  iclp = iclip + 512;
  for (i = -512; i < 512; i++)
    iclp[i] = (i < -256) ? -256 : ((i > 255) ? 255 : i);

  idct_int32((short *) tab);
  exit (0);
}