From 4ce6a76b0946e4ba943d29c506c9e2fb00601efd Mon Sep 17 00:00:00 2001 From: Scott Gasch Date: Thu, 27 Aug 2026 07:41:41 -0700 Subject: Baseline: uPositional data-calibrated fix, enprise/trapped hints, EBF/beta-cutoff/counter-move stats, script.c FPE fix. No LMR, no counter-move-driven move ordering (both explored separately, kept out for now -- counter-move measured worse, ~655->647 solved on ecm879 @ sn=4M with a leaner tree beforehand). Futility pruning restored. Verified: 647/879 solved, EBF 4.609 @ sn=4M; 684/879 solved, EBF 3.995 @ 20s/move, 1cpu, 256m hash (typhoon_baseline.log). The counter-move table is still written and its stats still tracked (dynamic.c) for diagnostic purposes, but generate.c no longer reads it for move ordering, so it has no effect on search behavior in this commit. lmr_testing/ holds the in-flight graded-LMR + counter-move code (not applied here) with notes on what was already tried and measured, so a future session can resume without re-deriving it. --- src/split.c | 35 +++++++++++++++++++---------------- 1 file changed, 19 insertions(+), 16 deletions(-) (limited to 'src/split.c') diff --git a/src/split.c b/src/split.c index bbaa518..2672c0c 100755 --- a/src/split.c +++ b/src/split.c @@ -1122,23 +1122,26 @@ Return value: } // - // Decide whether to history prune + // Decide how much (if any) to reduce this move's depth. // - if (TRUE == WeShouldDoHistoryPruning(iRoughEval, - iAlpha, - iBeta, - ctx, - uDepth, - (g_SplitInfo[u].uAlreadyDone + - uMoveNum + 1), - mv, - (g_SplitInfo[u].uAlreadyDone + - uMoveNum + 1), - iExtend)) { - ASSERT(iExtend == 0); - iExtend = -ONE_PLY; - ctx->sPlyInfo[ctx->uPly].iExtensionAmount = -ONE_PLY; + INT iLMR = GetLMRReduction(iRoughEval, + iAlpha, + iBeta, + ctx, + uDepth, + (g_SplitInfo[u].uAlreadyDone + + uMoveNum + 1), + mv, + (g_SplitInfo[u].uAlreadyDone + + uMoveNum + 1), + iExtend); + if (iLMR < 0) + { + ASSERT(iExtend == 0); + iExtend = iLMR; + ctx->sPlyInfo[ctx->uPly].iExtensionAmount = iLMR; + } } // @@ -1159,7 +1162,7 @@ Return value: // if ((iExtend < 0) && (iScore >= iBeta)) { - uDepth += ONE_PLY; + uDepth -= iExtend; // undo the full reduction, whatever its magnitude ctx->sPlyInfo[ctx->uPly].iExtensionAmount = 0; iScore = -Search(ctx, -iBeta, -iAlpha, uDepth); } -- cgit v1.3