h48

portable.h (5293B)

---

 #define STATIC_CUBE(c_ufr, c_ubl, c_dfl, c_dbr, c_ufl, c_ubr, c_dfr, c_dbl, \
     e_uf, e_ub, e_db, e_df, e_ur, e_ul, e_dl, e_dr, e_fr, e_fl, e_bl, e_br) \
     ((cube_t) { \
         .corner = { c_ufr, c_ubl, c_dfl, c_dbr, c_ufl, c_ubr, c_dfr, c_dbl }, \
         .edge = { e_uf, e_ub, e_db, e_df, e_ur, e_ul, \
                   e_dl, e_dr, e_fr, e_fl, e_bl, e_br } })
 #define ZERO_CUBE STATIC_CUBE( \
     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0)
 #define SOLVED_CUBE STATIC_CUBE( \
     0, 1, 2, 3, 4, 5, 6, 7, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11)
 
 /* TODO: optimize this (use bit tricks?) */
 STATIC_INLINE int
 popcount_u32(uint32_t x)
 {
 	int ret;
 
 	for (ret = 0; x != 0; x >>= 1)
 		ret += x & 1;
 
 	return ret;
 }
 
 STATIC void
 pieces(cube_t *cube, uint8_t c[static 8], uint8_t e[static 12])
 {
 	memcpy(c, cube->corner, 8);
 	memcpy(e, cube->edge, 12);
 }
 
 STATIC_INLINE bool
 equal(cube_t c1, cube_t c2)
 {
 	uint8_t i;
 	bool ret;
 
 	ret = true;
 	for (i = 0; i < 8; i++)
 		ret = ret && c1.corner[i] == c2.corner[i];
 	for (i = 0; i < 12; i++)
 		ret = ret && c1.edge[i] == c2.edge[i];
 
 	return ret;
 }
 
 STATIC_INLINE cube_t
 invertco(cube_t c)
 {
 	uint8_t i, piece, orien;
 	cube_t ret;
 
 	ret = c;
 	for (i = 0; i < 8; i++) {
 		piece = c.corner[i];
 		orien = ((piece << 1) | (piece >> 1)) & COBITS_2;
 		ret.corner[i] = (piece & PBITS) | orien;
 	}
 
 	return ret;
 }
 
 STATIC_INLINE void
 compose_edges_inplace(cube_t c1, cube_t c2, cube_t *ret)
 {
 	uint8_t i, piece1, piece2, p, orien;
 
 	for (i = 0; i < 12; i++) {
 		piece2 = c2.edge[i];
 		p = piece2 & PBITS;
 		piece1 = c1.edge[p];
 		orien = (piece2 ^ piece1) & EOBIT;
 		ret->edge[i] = (piece1 & PBITS) | orien;
 	}
 }
 
 STATIC_INLINE void
 compose_corners_inplace(cube_t c1, cube_t c2, cube_t *ret)
 {
 	uint8_t i, piece1, piece2, p, orien, aux, auy;
 
 	for (i = 0; i < 8; i++) {
 		piece2 = c2.corner[i];
 		p = piece2 & PBITS;
 		piece1 = c1.corner[p];
 		aux = (piece2 & COBITS) + (piece1 & COBITS);
 		auy = (aux + CTWIST_CW) >> 2;
 		orien = (aux + auy) & COBITS_2;
 		ret->corner[i] = (piece1 & PBITS) | orien;
 	}
 }
 
 STATIC_INLINE cube_t
 compose_edges(cube_t c1, cube_t c2)
 {
 	cube_t ret = ZERO_CUBE;
 
 	compose_edges_inplace(c1, c2, &ret);
 
 	return ret;
 }
 
 STATIC_INLINE cube_t
 compose_corners(cube_t c1, cube_t c2)
 {
 	cube_t ret = ZERO_CUBE;
 
 	compose_corners_inplace(c1, c2, &ret);
 
 	return ret;
 }
 
 STATIC_INLINE cube_t
 compose(cube_t c1, cube_t c2)
 {
 	cube_t ret = ZERO_CUBE;
 
 	compose_edges_inplace(c1, c2, &ret);
 	compose_corners_inplace(c1, c2, &ret);
 
 	return ret;
 }
 
 cube_t
 inverse(cube_t cube)
 {
 	uint8_t i, piece, orien;
 	cube_t ret;
 
 	for (i = 0; i < 12; i++) {
 		piece = cube.edge[i];
 		orien = piece & EOBIT;
 		ret.edge[piece & PBITS] = i | orien;
 	}
 
 	for (i = 0; i < 8; i++) {
 		piece = cube.corner[i];
 		orien = ((piece << 1) | (piece >> 1)) & COBITS_2;
 		ret.corner[piece & PBITS] = i | orien;
 	}
 
 	return ret;
 }
 
 STATIC_INLINE int64_t
 coord_co(cube_t c)
 {
 	int i, p;
 	int64_t ret;
 
 	for (ret = 0, i = 0, p = 1; i < 7; i++, p *= 3)
 		ret += p * (c.corner[i] >> COSHIFT);
 
 	return ret;
 }
 
 /*
 For corner separation, we consider the axis (a.k.a. tetrad) each
 corner belongs to as 0 or 1 and we translate this sequence into binary.
 Ignoring the last bit, we have a value up to 2^7, but not all values are
 possible. Encoding this as a number from 0 to C(8,4) would save about 40%
 of space, but we are not going to use this coordinate in large tables.
 */
 STATIC_INLINE int64_t
 coord_csep(cube_t c)
 {
 	int i, p;
 	int64_t ret;
 
 	for (ret = 0, i = 0, p = 1; i < 7; i++, p *= 2)
 		ret += p * ((c.corner[i] & CSEPBIT) >> 2);
 
 	return ret;
 }
 
 STATIC_INLINE int64_t
 coord_cocsep(cube_t c)
 {
 	return (coord_co(c) << 7) + coord_csep(c);
 }
 
 STATIC_INLINE int64_t
 coord_eo(cube_t c)
 {
 	int i, p;
 	int64_t ret;
 
 	for (ret = 0, i = 1, p = 1; i < 12; i++, p *= 2)
 		ret += p * (c.edge[i] >> EOSHIFT);
 
 	return ret;
 }
 
 /*
 We encode the edge separation as a number from 0 to C(12,4)*C(8,4).
 It can be seen as the composition of two "subset index" coordinates.
 */
 STATIC_INLINE int64_t
 coord_esep(cube_t c)
 {
 	int64_t i, j, jj, k, l, ret1, ret2, bit1, bit2, is1;
 
 	for (i = 0, j = 0, k = 4, l = 4, ret1 = 0, ret2 = 0; i < 12; i++) {
 		/* Simple version:
 		if (c.edge[i] & ESEPBIT_2) {
 			ret1 += binomial[11-i][k--];
 		} else {
 			if (c.edge[i] & ESEPBIT_1)
 				ret2 += binomial[7-j][l--];
 			j++;
 		}
 		*/
 
 		bit1 = (c.edge[i] & ESEPBIT_1) >> 2;
 		bit2 = (c.edge[i] & ESEPBIT_2) >> 3;
 		is1 = (1 - bit2) * bit1;
 
 		ret1 += bit2 * binomial[11-i][k];
 		k -= bit2;
 
 		jj = j < 8;
 		ret2 += jj * is1 * binomial[7-(j*jj)][l];
 		l -= is1;
 		j += (1-bit2);
 	}
 
 	return ret1 * 70 + ret2;
 }
 
 STATIC_INLINE void
 copy_corners(cube_t *dest, cube_t src)
 {
 	memcpy(&dest->corner, src.corner, sizeof(src.corner));
 }
 
 STATIC_INLINE void
 copy_edges(cube_t *dest, cube_t src)
 {
 	memcpy(&dest->edge, src.edge, sizeof(src.edge));
 }
 
 STATIC_INLINE void
 set_eo(cube_t *cube, int64_t eo)
 {
 	uint8_t i, sum, flip;
 
 	for (sum = 0, i = 1; i < 12; i++, eo >>= 1) {
 		flip = eo % 2;
 		sum += flip;
 		cube->edge[i] = (cube->edge[i] & ~EOBIT) | (EOBIT * flip);
 	}
 	cube->edge[0] = (cube->edge[0] & ~EOBIT) | (EOBIT * (sum % 2));
 }
 
 STATIC_INLINE cube_t
 invcoord_esep(int64_t esep)
 {
 	cube_t ret;
 
 	ret = SOLVED_CUBE;
 	invcoord_esep_array(esep % 70, esep / 70, ret.edge);
 
 	return ret;
 }