From 241156da6f35cb888253e6b8814e7b61a76b4fc7 Mon Sep 17 00:00:00 2001 From: tslil Date: Sun, 30 Aug 2026 19:46:07 +0100 Subject: TD(lambda), and a big rework NOTE: 6x6 weights are as-yet untrained On the performance side: * switch from linked-list chaining hash table to direct mapping * cache check_win by hash * persist transposition tables across plies (this was a big deal and difficult to puzzle out) * add align directives to the network floats * prepare_nn_input gained a small LUT to avoid branching (i suppose you might call this 1D embedding) * apply mtune=native for the native builds On the correctness side: * Zobrist has now includes the ply parity * the network now predicts something in [-1, 1] using tanh (approximated by polynomials) * the training object is now MSE because we're learning a value estimate * use .clangd instead of compile_commands.json On the training side: * completely forgo human-derived data set * implement td(lambda), self-play, tournaments --- include/tt.c | 60 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 60 insertions(+) create mode 100644 include/tt.c (limited to 'include/tt.c') diff --git a/include/tt.c b/include/tt.c new file mode 100644 index 0000000..b1f583e --- /dev/null +++ b/include/tt.c @@ -0,0 +1,60 @@ +/* + This file is part of ctak. + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation, either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, but + WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + General Public License for more details. + + You should have received a copy of the GNU General Public License + along with ctak. If not, see . +*/ + +#include "tt.h" +#include + +// =================================================================== +// Variables +// =================================================================== + +static tt_entry_t table[TT_SIZE + 1]; +static uint16_t tt_gen = 0; + +// =================================================================== +// Exported functions +// =================================================================== + +int tt_init(void) { + tt_gen++; + if (tt_gen == 0) + memset(table, 0, sizeof(table)); + return EXIT_SUCCESS; +} + +tt_entry_t *tt_seek(const uint64_t key) { + tt_entry_t *e = &table[key & TT_SIZE]; + if (e->gen == tt_gen && e->key == key) + return e; + return NULL; +} + +int tt_insert(const uint64_t key, const enum TT_FLAG flag, + const uint8_t depth, const float value, + const action_t action) { + tt_entry_t *e = &table[key & TT_SIZE]; + // Replacement scheme: keep a stale-but-deeper entry over a shallower new one. + if (e->gen == tt_gen && e->depth > depth) + return EXIT_SUCCESS; + e->key = key; + e->value = value; + e->action = action; + e->gen = tt_gen; + e->flag = flag; + e->depth = depth; + return EXIT_SUCCESS; +} -- cgit v1.3.1