From f1591447cf791b6c0ed4710df7eb688c65c4c20e Mon Sep 17 00:00:00 2001 From: Marco Costalba Date: Mon, 25 May 2009 07:28:55 +0100 Subject: [PATCH] Revert _BitScanForward64 support It shows almost no improvment and adds a good bunch of complexity. So remove for now. No functional change. Signed-off-by: Marco Costalba --- src/bitcount.h | 24 ---------- src/movegen.cpp | 124 +++++++++++++++++++----------------------------- 2 files changed, 50 insertions(+), 98 deletions(-) diff --git a/src/bitcount.h b/src/bitcount.h index 871247ab..d57b3f40 100644 --- a/src/bitcount.h +++ b/src/bitcount.h @@ -66,7 +66,6 @@ inline bool cpu_has_popcnt() { } #define POPCNT_INTRINSIC(x) __popcnt64(x) -#define BITSCAN_INTRINSIC(idx, x) _BitScanForward64(idx, x) #elif defined(__INTEL_COMPILER) && (defined(__x86_64) || defined(_M_X64)) // Intel compiler @@ -80,14 +79,12 @@ inline bool cpu_has_popcnt() { } #define POPCNT_INTRINSIC(x) _mm_popcnt_u64(x) -#define BITSCAN_INTRINSIC(idx, x) _BitScanForward64(idx, x) #else // Safe fallback for unsupported compilers inline bool cpu_has_popcnt() { return false; } #define POPCNT_INTRINSIC(x) count_1s(x) -#define BITSCAN_INTRINSIC(idx, x) count_1s(x) // dummy #endif @@ -168,27 +165,6 @@ inline int count_1s_max_15(Bitboard b) { } -/// pop_1st_bit() finds and clears the least significant nonzero bit in a -/// nonzero bitboard. If template parameter is true an intrinsic is called, -/// otherwise we fallback on a software implementation. - -template -inline Square pop_1st_bit(Bitboard *b) { - - return pop_1st_bit(b); -} - -template<> -inline Square pop_1st_bit(Bitboard *b) { - - unsigned long idx; - Bitboard bb = *b; - BITSCAN_INTRINSIC(&idx, bb); - *b &= (bb - 1); - return Square(idx); -} - - // Global variable initialized at startup that is set to true if // CPU on which application runs supports POPCNT intrinsic. Unless // DISABLE_POPCNT_SUPPORT is defined. diff --git a/src/movegen.cpp b/src/movegen.cpp index 8a03acd6..1135c219 100644 --- a/src/movegen.cpp +++ b/src/movegen.cpp @@ -29,7 +29,7 @@ // Simple macro to wrap a very common while loop, no facny, no flexibility, // hardcoded list name 'mlist' and from square 'from'. -#define SERIALIZE_MOVES(b, bsf) while (b) (*mlist++).move = make_move(from, pop_1st_bit(&b)) +#define SERIALIZE_MOVES(b) while (b) (*mlist++).move = make_move(from, pop_1st_bit(&b)) //// //// Local definitions @@ -83,22 +83,22 @@ namespace { } // Template generate_piece_checks() with specializations - template + template MoveStack* generate_piece_checks(const Position&, MoveStack*, Color, Bitboard, Square); template<> - inline MoveStack* generate_piece_checks(const Position& p, MoveStack* m, Color us, Bitboard dc, Square ksq) { + inline MoveStack* generate_piece_checks(const Position& p, MoveStack* m, Color us, Bitboard dc, Square ksq) { return (us == WHITE ? generate_pawn_checks(p, dc, ksq, m) : generate_pawn_checks(p, dc, ksq, m)); } // Template generate_piece_moves() with specializations and overloads - template + template MoveStack* generate_piece_moves(const Position&, MoveStack*, Color us, Bitboard); template<> - MoveStack* generate_piece_moves(const Position&, MoveStack*, Color, Bitboard); + MoveStack* generate_piece_moves(const Position&, MoveStack*, Color, Bitboard); template inline MoveStack* generate_piece_moves(const Position& p, MoveStack* m, Color us) { @@ -113,12 +113,12 @@ namespace { : generate_pawn_noncaptures(p, m)); } - template + template MoveStack* generate_piece_moves(const Position&, MoveStack*, Color us, Bitboard, Bitboard); template<> - inline MoveStack* generate_piece_moves(const Position& p, MoveStack* m, - Color us, Bitboard t, Bitboard pnd) { + inline MoveStack* generate_piece_moves(const Position& p, MoveStack* m, + Color us, Bitboard t, Bitboard pnd) { return (us == WHITE ? generate_pawn_blocking_evasions(p, pnd, t, m) : generate_pawn_blocking_evasions(p, pnd, t, m)); @@ -133,7 +133,7 @@ namespace { /// generate_captures generates() all pseudo-legal captures and queen /// promotions. The return value is the number of moves generated. -template + int generate_captures(const Position& pos, MoveStack* mlist) { assert(pos.is_ok()); @@ -143,25 +143,19 @@ int generate_captures(const Position& pos, MoveStack* mlist) { Bitboard target = pos.pieces_of_color(opposite_color(us)); MoveStack* mlist_start = mlist; - mlist = generate_piece_moves(pos, mlist, us, target); - mlist = generate_piece_moves(pos, mlist, us, target); - mlist = generate_piece_moves(pos, mlist, us, target); - mlist = generate_piece_moves(pos, mlist, us, target); + mlist = generate_piece_moves(pos, mlist, us, target); + mlist = generate_piece_moves(pos, mlist, us, target); + mlist = generate_piece_moves(pos, mlist, us, target); + mlist = generate_piece_moves(pos, mlist, us, target); mlist = generate_piece_moves(pos, mlist, us); - mlist = generate_piece_moves(pos, mlist, us, target); + mlist = generate_piece_moves(pos, mlist, us, target); return int(mlist - mlist_start); } -int generate_captures(const Position& pos, MoveStack* mlist) { - - return CpuHasPOPCNT ? generate_captures(pos, mlist) - : generate_captures(pos, mlist); -} - /// generate_noncaptures() generates all pseudo-legal non-captures and /// underpromotions. The return value is the number of moves generated. -template + int generate_noncaptures(const Position& pos, MoveStack* mlist) { assert(pos.is_ok()); @@ -172,26 +166,20 @@ int generate_noncaptures(const Position& pos, MoveStack* mlist) { MoveStack* mlist_start = mlist; mlist = generate_piece_moves(pos, mlist, us); - mlist = generate_piece_moves(pos, mlist, us, target); - mlist = generate_piece_moves(pos, mlist, us, target); - mlist = generate_piece_moves(pos, mlist, us, target); - mlist = generate_piece_moves(pos, mlist, us, target); - mlist = generate_piece_moves(pos, mlist, us, target); + mlist = generate_piece_moves(pos, mlist, us, target); + mlist = generate_piece_moves(pos, mlist, us, target); + mlist = generate_piece_moves(pos, mlist, us, target); + mlist = generate_piece_moves(pos, mlist, us, target); + mlist = generate_piece_moves(pos, mlist, us, target); mlist = generate_castle_moves(pos, mlist); mlist = generate_castle_moves(pos, mlist); return int(mlist - mlist_start); } -int generate_noncaptures(const Position& pos, MoveStack* mlist) { - - return CpuHasPOPCNT ? generate_noncaptures(pos, mlist) - : generate_noncaptures(pos, mlist); -} - /// generate_non_capture_checks() generates all pseudo-legal non-capturing, /// non-promoting checks. It returns the number of generated moves. -template + int generate_non_capture_checks(const Position& pos, MoveStack* mlist, Bitboard dc) { assert(pos.is_ok()); @@ -204,12 +192,12 @@ int generate_non_capture_checks(const Position& pos, MoveStack* mlist, Bitboard assert(pos.piece_on(ksq) == piece_of_color_and_type(opposite_color(us), KING)); // Pieces moves - mlist = generate_piece_checks(pos, mlist, us, dc, ksq); - mlist = generate_piece_checks(pos, mlist, us, dc, ksq); - mlist = generate_piece_checks(pos, mlist, us, dc, ksq); - mlist = generate_piece_checks(pos, mlist, us, dc, ksq); - mlist = generate_piece_checks(pos, mlist, us, dc, ksq); - mlist = generate_piece_checks(pos, mlist, us, dc, ksq); + mlist = generate_piece_checks(pos, mlist, us, dc, ksq); + mlist = generate_piece_checks(pos, mlist, us, dc, ksq); + mlist = generate_piece_checks(pos, mlist, us, dc, ksq); + mlist = generate_piece_checks(pos, mlist, us, dc, ksq); + mlist = generate_piece_checks(pos, mlist, us, dc, ksq); + mlist = generate_piece_checks(pos, mlist, us, dc, ksq); // Castling moves that give check. Very rare but nice to have! if ( pos.can_castle_queenside(us) @@ -225,17 +213,11 @@ int generate_non_capture_checks(const Position& pos, MoveStack* mlist, Bitboard return int(mlist - mlist_start); } -int generate_non_capture_checks(const Position& pos, MoveStack* mlist, Bitboard dc) { - - return CpuHasPOPCNT ? generate_non_capture_checks(pos, mlist, dc) - : generate_non_capture_checks(pos, mlist, dc); -} - /// generate_evasions() generates all check evasions when the side to move is /// in check. Unlike the other move generation functions, this one generates /// only legal moves. It returns the number of generated moves. -template + int generate_evasions(const Position& pos, MoveStack* mlist, Bitboard pinned) { assert(pos.is_ok()); @@ -262,14 +244,14 @@ int generate_evasions(const Position& pos, MoveStack* mlist, Bitboard pinned) { Bitboard b = checkers & (pos.queens() | pos.bishops()); while (b) { - from = pop_1st_bit(&b); + from = pop_1st_bit(&b); checkersAttacks |= bishop_attacks_bb(from, b_noKing); } b = checkers & (pos.queens() | pos.rooks()); while (b) { - from = pop_1st_bit(&b); + from = pop_1st_bit(&b); checkersAttacks |= rook_attacks_bb(from, b_noKing); } @@ -277,7 +259,7 @@ int generate_evasions(const Position& pos, MoveStack* mlist, Bitboard pinned) { Bitboard b1 = pos.piece_attacks(ksq) & ~pos.pieces_of_color(us) & ~checkersAttacks; while (b1) { - to = pop_1st_bit(&b1); + to = pop_1st_bit(&b1); // Note that we can use square_is_attacked() only because we // have already removed slider checkers. if (!pos.square_is_attacked(to, them)) @@ -299,7 +281,7 @@ int generate_evasions(const Position& pos, MoveStack* mlist, Bitboard pinned) { b1 = pos.pawn_attacks(them, checksq) & pos.pawns(us) & ~pinned; while (b1) { - from = pop_1st_bit(&b1); + from = pop_1st_bit(&b1); if (relative_rank(us, checksq) == RANK_8) { (*mlist++).move = make_promotion_move(from, checksq, QUEEN); @@ -317,7 +299,7 @@ int generate_evasions(const Position& pos, MoveStack* mlist, Bitboard pinned) { while (b1) { - from = pop_1st_bit(&b1); + from = pop_1st_bit(&b1); (*mlist++).move = make_move(from, checksq); } @@ -331,11 +313,11 @@ int generate_evasions(const Position& pos, MoveStack* mlist, Bitboard pinned) { if (blockSquares != EmptyBoardBB) { - mlist = generate_piece_moves(pos, mlist, us, blockSquares, pinned); - mlist = generate_piece_moves(pos, mlist, us, blockSquares, pinned); - mlist = generate_piece_moves(pos, mlist, us, blockSquares, pinned); - mlist = generate_piece_moves(pos, mlist, us, blockSquares, pinned); - mlist = generate_piece_moves(pos, mlist, us, blockSquares, pinned); + mlist = generate_piece_moves(pos, mlist, us, blockSquares, pinned); + mlist = generate_piece_moves(pos, mlist, us, blockSquares, pinned); + mlist = generate_piece_moves(pos, mlist, us, blockSquares, pinned); + mlist = generate_piece_moves(pos, mlist, us, blockSquares, pinned); + mlist = generate_piece_moves(pos, mlist, us, blockSquares, pinned); } } @@ -357,7 +339,7 @@ int generate_evasions(const Position& pos, MoveStack* mlist, Bitboard pinned) { b1 &= ~pinned; while (b1) { - from = pop_1st_bit(&b1); + from = pop_1st_bit(&b1); // Move is always legal because checking pawn is not a discovered // check candidate and our capturing pawn has been already tested // against pinned pieces. @@ -368,12 +350,6 @@ int generate_evasions(const Position& pos, MoveStack* mlist, Bitboard pinned) { return int(mlist - mlist_start); } -int generate_evasions(const Position& pos, MoveStack* mlist, Bitboard pinned) { - - return CpuHasPOPCNT ? generate_evasions(pos, mlist, pinned) - : generate_evasions(pos, mlist, pinned); -} - /// generate_legal_moves() computes a complete list of legal moves in the /// current position. This function is not very fast, and should be used @@ -590,7 +566,7 @@ bool move_is_legal(const Position& pos, const Move m, Bitboard pinned) { namespace { - template + template MoveStack* generate_piece_moves(const Position& pos, MoveStack* mlist, Color us, Bitboard target) { Square from; @@ -600,12 +576,12 @@ namespace { { from = pos.piece_list(us, Piece, i); b = pos.piece_attacks(from) & target; - SERIALIZE_MOVES(b, HasBSF); + SERIALIZE_MOVES(b); } return mlist; } - template + template MoveStack* generate_piece_moves(const Position& pos, MoveStack* mlist, Color us, Bitboard target, Bitboard pinned) { Square from; @@ -618,19 +594,19 @@ namespace { continue; b = pos.piece_attacks(from) & target; - SERIALIZE_MOVES(b, HasBSF); + SERIALIZE_MOVES(b); } return mlist; } template<> - MoveStack* generate_piece_moves(const Position& pos, MoveStack* mlist, Color us, Bitboard target) { + MoveStack* generate_piece_moves(const Position& pos, MoveStack* mlist, Color us, Bitboard target) { Bitboard b; Square from = pos.king_square(us); b = pos.piece_attacks(from) & target; - SERIALIZE_MOVES(b, false); + SERIALIZE_MOVES(b); return mlist; } @@ -840,7 +816,7 @@ namespace { return mlist; } - template + template MoveStack* generate_piece_checks(const Position& pos, MoveStack* mlist, Color us, Bitboard dc, Square ksq) { @@ -850,12 +826,12 @@ namespace { Bitboard b = target & dc; while (b) { - Square from = pop_1st_bit(&b); + Square from = pop_1st_bit(&b); Bitboard bb = pos.piece_attacks(from) & pos.empty_squares(); if (Piece == KING) bb &= ~QueenPseudoAttacks[ksq]; - SERIALIZE_MOVES(bb, HasBSF); + SERIALIZE_MOVES(bb); } // Direct checks @@ -868,14 +844,14 @@ namespace { while (b) { - Square from = pop_1st_bit(&b); + Square from = pop_1st_bit(&b); if ( (Piece == QUEEN && !(QueenPseudoAttacks[from] & checkSqs)) || (Piece == ROOK && !(RookPseudoAttacks[from] & checkSqs)) || (Piece == BISHOP && !(BishopPseudoAttacks[from] & checkSqs))) continue; Bitboard bb = pos.piece_attacks(from) & checkSqs; - SERIALIZE_MOVES(bb, HasBSF); + SERIALIZE_MOVES(bb); } } return mlist; -- 2.39.2