chess-asm

chess-asm is a low-level implementation of a chess game, written entirely in x86-64 assembly. It explores the extreme performance benefits of using bitboards and direct hardware manipulation for move generation.

Engineering Highlights

• Bitboard Representation: Uses 64-bit integers to represent the board state, where each bit corresponds to a square. This allows for move generation and state updates using single-instruction bitwise operations.
• Highly Optimized Routines: Implemented core move generation logic directly in assembly to eliminate compiler abstraction overhead and maximize register usage.
• 32-bit Compatibility Layer: Designed a split “high/low” bitboard system to support 32-bit architectures while maintaining 64-bit logical correctness.
• Graphical Output: Utilizes Mode 13h for direct video buffer manipulation, providing a custom graphical interface for the board and pieces.
• Lock-Free Board Logic: Designed the move generation functions to be stateless and branch-minimized, ensuring high throughput during engine search phases.