Add raw_* methods to bit32 and bit64 for efficient bit operations #11
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…erations This adds raw_* variants of all bit operations that bypass the to_unsigned() wrapper on LuaJIT, providing direct access to native bit library functions. For XOR, AND, OR, and rotate operations, the signedness doesn't matter since bit patterns are identical. New functions in bit32: - raw_band, raw_bor, raw_bxor, raw_bnot - raw_lshift, raw_rshift, raw_arshift - raw_rol, raw_ror - raw_add New functions in bit64: - raw_band, raw_bor, raw_bxor, raw_bnot - raw_lshift, raw_rshift, raw_arshift - raw_rol, raw_ror - raw_add Key implementation details: - On LuaJIT: raw_* are direct references to bit.* functions (zero overhead) - On Lua 5.3+: raw_* use native operators with 32-bit masking for shifts - On Lua 5.2: raw_* are direct references to bit32.* (already unsigned) - On Pure Lua: raw_* fall back to safe implementations (no native library) - raw_rol/raw_ror fall back to computed versions on non-LuaJIT (not nil) Note: Shift amounts >= 32 (or >= 64 for bit64) have platform-specific behavior. LuaJIT wraps (n % 32), Lua 5.3+ returns 0. Callers should keep n in valid range.
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This pull request introduces
raw_*methods for bitwise operations in thebit32andbit64modules, allowing zero-overhead access to native bit library functions across different Lua versions. The addition includes:bit32:raw_band,raw_bor,raw_bxor,raw_bnot,raw_lshift,raw_rshift,raw_arshift,raw_rol,raw_ror, andraw_add.bit64:raw_band,raw_bor,raw_bxor,raw_bnot,raw_lshift,raw_rshift,raw_arshift,raw_rol,raw_ror, andraw_add.Implementation details:
bit.*for zero overhead.bit32.*.Note: Behavior for shift amounts beyond bounds (e.g., >=32 or >=64) varies across Lua implementations. It is the caller's responsibility to ensure valid ranges for such amounts.