#define mpn_toomN_sqr mpn_toom2_sqr #define mpn_toomN_sqr_itch mpn_toom2_sqr_itch #define MIN_AN MPN_TOOM2_SQR_MINSIZE #define MAX_AN SQR_TOOM3_THRESHOLD #define MORE_SQR_TESTS explore_unlikely_branch #include "toom-sqr-shared.h" void explore_unlikely_branch (gmp_randstate_ptr rands) { mp_ptr ap, refp, pp, scratch; mp_size_t an; mp_bitcnt_t bit; TMP_DECL; TMP_MARK; ap = TMP_ALLOC_LIMBS (MAX_AN); refp = TMP_ALLOC_LIMBS (MAX_AN * 2); pp = 1 + TMP_ALLOC_LIMBS (MAX_AN * 2 + 2); scratch = 1+TMP_ALLOC_LIMBS (mpn_toomN_sqr_itch (MAX_AN) + 2); for (an = MIN_AN + (MIN_AN & 1); an < MAX_AN; an+=2) { mp_size_t itch; mp_limb_t p_before, p_after, s_before, s_after; bit = an / 2 * GMP_NUMB_BITS + gmp_urandomm_ui (rands, an / 2 * GMP_NUMB_BITS - 1); mpn_zero (ap, an); mpn_zero (pp, an * 2); pp [an - 1] |= GMP_NUMB_HIGHBIT; pp [bit / GMP_NUMB_BITS] |= CNST_LIMB (1) << (bit % GMP_NUMB_BITS); mpn_sqrtrem (ap, NULL, pp, an); /* We need {ap, an} such that {ap + an/2, an/2} is zero and the result {pp, 2*an} is such that the sum {pp, an/2} + {pp + an/2, an/2} gives a carry. */ mpn_random2 (pp-1, an * 2 + 2); p_before = pp[-1]; p_after = pp[an * 2]; itch = mpn_toomN_sqr_itch (an); ASSERT_ALWAYS (itch <= mpn_toomN_sqr_itch (MAX_AN)); mpn_random2 (scratch-1, itch+2); s_before = scratch[-1]; s_after = scratch[itch]; mpn_toomN_sqr (pp, ap, an, scratch); refmpn_mul (refp, ap, an, ap, an); if (pp[-1] != p_before || pp[an * 2] != p_after || scratch[-1] != s_before || scratch[itch] != s_after || mpn_cmp (refp, pp, an * 2) != 0) { printf ("ERROR with bit %lu, an = %d\n", (unsigned long) bit, (int) an); if (pp[-1] != p_before) { printf ("before pp:"); mpn_dump (pp -1, 1); printf ("keep: "); mpn_dump (&p_before, 1); } if (pp[an * 2] != p_after) { printf ("after pp:"); mpn_dump (pp + an * 2, 1); printf ("keep: "); mpn_dump (&p_after, 1); } if (scratch[-1] != s_before) { printf ("before scratch:"); mpn_dump (scratch-1, 1); printf ("keep: "); mpn_dump (&s_before, 1); } if (scratch[itch] != s_after) { printf ("after scratch:"); mpn_dump (scratch + itch, 1); printf ("keep: "); mpn_dump (&s_after, 1); } mpn_dump (ap, an); mpn_dump (pp, an * 2); mpn_dump (refp, an * 2); abort(); } } TMP_FREE; }