ARM: More intrinsics

[Andrew Haley]

On 03/15/2012 07:06 PM, pcpa at mandriva.com.br wrote:
>   I just made the attached simple test program, that may be useful
> for adapting it to the logic you use, and validate it.

Thanks.  It gives the same results, and as because the test is
exhaustive proves that the logic in my it() is correct.

Ta,
Andrew.



static void
tcit(unsigned int tc, int it)
{
    int		m;

    assert(!(tc & 0xfffffff) && tc != ARM_CC_NV);
    switch (it) {
	case THUMB2_IT:		m =   1<<3; 			break;
	case THUMB2_ITT:	m =  (0<<3)| (1<<2);		break;
	case THUMB2_ITE:	m = (1<<3)| (1<<2);		break;
	case THUMB2_ITTT:	m =  (0<<3)| (0<<2)| (1<<1);	break;
	case THUMB2_ITET:	m = (1<<3)| (0<<2)| (1<<1);	break;
	case THUMB2_ITTE:	m =  (0<<3)|(1<<2)| (1<<1);	break;
	case THUMB2_ITEE:	m = (1<<3)|(1<<2)| (1<<1);	break;
	case THUMB2_ITTTT:	m =  (0<<3)| (0<<2)| (0<<1)|1;	break;
	case THUMB2_ITETT:	m = (1<<3)| (0<<2)| (0<<1)|1;	break;
	case THUMB2_ITTET:	m =  (0<<3)|(1<<2)| (0<<1)|1;	break;
	case THUMB2_ITEET:	m = (1<<3)|(1<<2)| (0<<1)|1;	break;
	case THUMB2_ITTTE:	m =  (0<<3)| (0<<2)|(1<<1)|1;	break;
	case THUMB2_ITETE:	m = (1<<3)| (0<<2)|(1<<1)|1;	break;
	case THUMB2_ITTEE:	m =  (0<<3)|(1<<2)|(1<<1)|1;	break;
	case THUMB2_ITEEE:	m = (1<<3)|(1<<2)|(1<<1)|1;	break;
	default:		abort();
    }

    int negated = (tc >> 28) & 1;

    if ((tc >> 28) & 1) {
      // If this is a negated condition, flip all the bits above the
      // least significant bit that is 1.  Note that at least one bit is
      // always 1 in mask
      switch (m & (-m)) {
      case 8:
	break;
      case 4:
	m ^= 8;
	break;
      case 2:
	m ^= 0x0c;
	break;
      case 1:
	m ^= 0x0e;
	break;
      default:
	// Impossible unless someone specified an incorrect mask
	abort();
      }
    }
      assert(m && (tc != ARM_CC_AL || !(m & (m - 1))));
      is(0xbf00 | (tc >> 24) | m);
}