1 files changed, 319 insertions, 0 deletions

diff --git a/src/arch/avx2.h b/src/arch/avx2.h
new file mode 100644
index 0000000..59a0d6c
--- /dev/null
+++ b/src/arch/avx2.h
@@ -0,0 +1,319 @@
+#define _co2_avx2 _mm256_set_epi64x(0, 0, 0, INT64_C(0x6060606060606060))
+#define _cocw_avx2 _mm256_set_epi64x(0, 0, 0, INT64_C(0x2020202020202020))
+#define _cp_avx2 _mm256_set_epi64x(0, 0, 0, INT64_C(0x0707070707070707))
+#define _ep_avx2 \
+    _mm256_set_epi64x(INT64_C(0x0F0F0F0F), INT64_C(0x0F0F0F0F0F0F0F0F), 0, 0)
+#define _eo_avx2 \
+    _mm256_set_epi64x(INT64_C(0x10101010), INT64_C(0x1010101010101010), 0, 0)
+
+#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) \
+    _mm256_set_epi8(0, 0, 0, 0, e_br, e_bl, e_fl, e_fr, \
+        e_dr, e_dl, e_ul, e_ur, e_df, e_db, e_ub, e_uf, \
+        0, 0, 0, 0, 0, 0, 0, 0, \
+        c_dbl, c_dfr, c_ubr, c_ufl, c_dbr, c_dfl, c_ubl, c_ufr)
+#define zero _mm256_set_epi64x(0, 0, 0, 0)
+#define solved static_cube( \
+    0, 1, 2, 3, 4, 5, 6, 7, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11)
+
+_static void
+pieces(cube_t *cube, uint8_t c[static 8], uint8_t e[static 12])
+{
+        uint8_t aux[32];
+
+        _mm256_storeu_si256((__m256i_u *)aux, *cube);
+        memcpy(c, aux, 8);
+        memcpy(e, aux+16, 12);
+}
+
+_static_inline bool
+equal(cube_t c1, cube_t c2)
+{
+        int32_t mask;
+        __m256i cmp;
+
+        cmp = _mm256_cmpeq_epi8(c1, c2);
+        mask = _mm256_movemask_epi8(cmp);
+
+        return mask == ~0;
+}
+
+_static_inline cube_t
+invertco(cube_t c)
+{
+        cube_t co, shleft, shright, summed, newco, cleanco, ret;
+
+        co = _mm256_and_si256(c, _co2_avx2);
+        shleft = _mm256_slli_epi32(co, 1);
+        shright = _mm256_srli_epi32(co, 1);
+        summed = _mm256_or_si256(shleft, shright);
+        newco = _mm256_and_si256(summed, _co2_avx2);
+        cleanco = _mm256_xor_si256(c, co);
+        ret = _mm256_or_si256(cleanco, newco);
+
+        return ret;
+}
+
+_static_inline cube_t
+compose_epcpeo(cube_t c1, cube_t c2)
+{
+        cube_t b, s, eo2;
+
+        /* Permute and clean unused bits */
+        s = _mm256_shuffle_epi8(c1, c2);
+        b = _mm256_set_epi8(
+                ~0, ~0, ~0, ~0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+                ~0, ~0, ~0, ~0, ~0, ~0, ~0, ~0, 0, 0, 0, 0, 0, 0, 0, 0
+        );
+        s = _mm256_andnot_si256(b, s);
+
+        /* Change EO */
+        eo2 = _mm256_and_si256(c2, _eo_avx2);
+        s = _mm256_xor_si256(s, eo2);
+
+        return s;
+}
+
+_static_inline cube_t
+compose_edges(cube_t c1, cube_t c2)
+{
+        return compose_epcpeo(c1, c2);
+}
+
+_static_inline cube_t
+compose_corners(cube_t c1, cube_t c2)
+{
+        /*
+         * We do a full compose. Minor optimizations are possible, like
+         * saving one instruction by not doing EO, but it should not
+         * be significant.
+         */
+        return compose(c1, c2);
+}
+
+_static_inline cube_t
+compose(cube_t c1, cube_t c2)
+{
+        cube_t s, co1, co2, aux, auy1, auy2, auz1, auz2;
+
+        s = compose_epcpeo(c1, c2);
+
+        /* Change CO */
+        co1 = _mm256_and_si256(s, _co2_avx2);
+        co2 = _mm256_and_si256(c2, _co2_avx2);
+        aux = _mm256_add_epi8(co1, co2);
+        auy1 = _mm256_add_epi8(aux, _cocw_avx2);
+        auy2 = _mm256_srli_epi32(auy1, 2);
+        auz1 = _mm256_add_epi8(aux, auy2);
+        auz2 = _mm256_and_si256(auz1, _co2_avx2);
+
+        /* Put together */
+        s = _mm256_andnot_si256(_co2_avx2, s);
+        s = _mm256_or_si256(s, auz2);
+
+        return s;
+}
+
+_static_inline cube_t
+cleanaftershuffle(cube_t c)
+{
+        __m256i b;
+
+        b = _mm256_set_epi8(
+                ~0, ~0, ~0, ~0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+                ~0, ~0, ~0, ~0, ~0, ~0, ~0, ~0, 0, 0, 0, 0, 0, 0, 0, 0
+        );
+
+        return _mm256_andnot_si256(b, c);
+}
+
+_static_inline cube_t
+inverse(cube_t c)
+{
+        /* Method taken from Andrew Skalski's vcube[1]. The addition sequence
+         * was generated using [2].
+         * [1] https://github.com/Voltara/vcube
+         * [2] http://wwwhomes.uni-bielefeld.de/achim/addition_chain.html
+         */
+        cube_t v3, vi, vo, vp, ret;
+
+        v3 = _mm256_shuffle_epi8(c, c);
+        v3 = _mm256_shuffle_epi8(v3, c);
+        vi = _mm256_shuffle_epi8(v3, v3);
+        vi = _mm256_shuffle_epi8(vi, vi);
+        vi = _mm256_shuffle_epi8(vi, vi);
+        vi = _mm256_shuffle_epi8(vi, v3);
+        vi = _mm256_shuffle_epi8(vi, vi);
+        vi = _mm256_shuffle_epi8(vi, vi);
+        vi = _mm256_shuffle_epi8(vi, vi);
+        vi = _mm256_shuffle_epi8(vi, vi);
+        vi = _mm256_shuffle_epi8(vi, c);
+        vi = _mm256_shuffle_epi8(vi, vi);
+        vi = _mm256_shuffle_epi8(vi, vi);
+        vi = _mm256_shuffle_epi8(vi, vi);
+        vi = _mm256_shuffle_epi8(vi, vi);
+        vi = _mm256_shuffle_epi8(vi, vi);
+        vi = _mm256_shuffle_epi8(vi, v3);
+        vi = _mm256_shuffle_epi8(vi, vi);
+        vi = _mm256_shuffle_epi8(vi, c);
+
+        vo = _mm256_and_si256(c, _mm256_or_si256(_eo_avx2, _co2_avx2));
+        vo = _mm256_shuffle_epi8(vo, vi);
+        vp = _mm256_andnot_si256(_mm256_or_si256(_eo_avx2, _co2_avx2), vi);
+        ret = _mm256_or_si256(vp, vo);
+        ret = cleanaftershuffle(ret);
+        
+        return invertco(ret);
+}
+
+_static_inline int64_t
+coord_co(cube_t c)
+{
+        cube_t co;
+        int64_t mem[4], ret, i, p;
+
+        co = _mm256_and_si256(c, _co2_avx2);
+        _mm256_storeu_si256((__m256i *)mem, co);
+
+        mem[0] >>= 5;
+        for (i = 0, ret = 0, p = 1; i < 7; i++, mem[0] >>= 8, p *= 3)
+                ret += (mem[0] & 3) * p;
+
+        return ret;
+}
+
+_static_inline int64_t
+coord_csep(cube_t c)
+{
+        cube_t cp, shifted;
+        int64_t mask;
+
+        cp = _mm256_and_si256(c, _cp_avx2);
+        shifted = _mm256_slli_epi32(cp, 5);
+        mask = _mm256_movemask_epi8(shifted);
+
+        return mask & 0x7F;
+}
+
+_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)
+{
+        cube_t eo, shifted;
+        int64_t mask;
+
+        eo = _mm256_and_si256(c, _eo_avx2);
+        shifted = _mm256_slli_epi32(eo, 3);
+        mask = _mm256_movemask_epi8(shifted);
+
+        return mask >> 17;
+}
+
+_static_inline int64_t
+coord_esep(cube_t c)
+{
+        cube_t ep;
+        int64_t e, mem[4], i, j, jj, k, l, ret1, ret2, bit1, bit2, is1;
+
+        ep = _mm256_and_si256(c, _ep_avx2);
+        _mm256_storeu_si256((__m256i *)mem, ep);
+
+        mem[3] <<= 8;
+        ret1 = ret2 = 0;
+        k = l = 4;
+        for (i = 0, j = 0; i < 12; i++, mem[i/8 + 2] >>= 8) {
+                e = mem[i/8 + 2];
+
+                bit1 = (e & _esepbit1) >> 2;
+                bit2 = (e & _esepbit2) >> 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)
+{
+        *dest = _mm256_blend_epi32(*dest, src, 0x0F);
+}
+
+_static_inline void
+copy_edges(cube_t *dest, cube_t src)
+{
+        *dest = _mm256_blend_epi32(*dest, src, 0xF0);
+}
+
+_static_inline void
+set_eo(cube_t *cube, int64_t eo)
+{
+        int64_t eo12, eotop, eobot;
+        __m256i veo;
+
+        eo12 = (eo << 1) + (_mm_popcnt_u64(eo) % 2);
+        eotop = (eo12 & (1 << 11)) << 17 |
+                (eo12 & (1 << 10)) << 10 |
+                (eo12 & (1 << 9)) << 3 |
+                (eo12 & (1 << 8)) >> 4;
+        eobot = (eo12 & (1 << 7)) << 53 |
+                (eo12 & (1 << 6)) << 46 |
+                (eo12 & (1 << 5)) << 39 |
+                (eo12 & (1 << 4)) << 32 |
+                (eo12 & (1 << 3)) << 25 |
+                (eo12 & (1 << 2)) << 18 |
+                (eo12 & (1 << 1)) << 11 |
+                (eo12 & 1) << 4;
+        veo = _mm256_set_epi64x(eotop, eobot, 0, 0);
+
+        *cube = _mm256_andnot_si256(_eo_avx2, *cube);
+        *cube = _mm256_or_si256(*cube, veo);
+}
+
+_static_inline cube_t
+invcoord_esep(int64_t esep)
+{
+        cube_t eee, ret;
+        int64_t bit1, bit2, i, j, jj, k, l, s, v, w, is1, set1, set2;
+        uint8_t mem[32];
+        uint8_t slice[3] = {0};
+
+        set1 = esep % 70;
+        set2 = esep / 70;
+
+        for (i = 0, j = 0, k = 4, l = 4; i < 12; i++) {
+                v = binomial[11-i][k];
+                jj = j < 8;
+                w = jj * binomial[7-(j*jj)][l];
+                bit2 = set2 >= v;
+                bit1 = set1 >= w;
+                is1 = (1 - bit2) * bit1;
+
+                set2 -= bit2 * v;
+                k -= bit2;
+                set1 -= is1 * w;
+                l -= is1;
+                j += (1-bit2);
+                s = 2*bit2 + (1-bit2)*bit1;
+
+                mem[i+16] = (slice[s]++) | (uint8_t)(s << 2);
+        }
+
+        ret = solved;
+        eee = _mm256_loadu_si256((__m256i_u *)&mem);
+        copy_edges(&ret, eee);
+
+        return ret;
+}