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  • win64-main-5e76554 5e76554514

    core: unify clock dispatch logic, add precise clocks, and enforce coalesced time writes (#71)

    Ghost released this 2026-07-11 16:39:44 -04:00 | 533 commits to 1016_part3 since this release

    Comprehensive refactoring of the system time subsystem to unify clock dispatching, support precise clock extensions, and secure memory boundaries against partial state corruption.

    Centralized Clock Dispatch Engine:

    • Extracted shared elapsed-tick calculation and clock-routing math into a unified internal static bool ResolveClockTime() dispatch engine under KernelRuntimeCompatExports.cs.
    • Moved all clock identifiers from KernelMemoryCompatExports to KernelRuntimeCompatExports as internal const int constants to eliminate cross-file duplication while preserving raw compiler switch-case layout optimizations.
    • Added native alias mapping support for CLOCK_REALTIME_PRECISE (9) and CLOCK_MONOTONIC_PRECISE (11).
    • Hardened the Orbis sceKernelClockGettime path by routing it through the new dispatcher, resolving a pre-existing logic flaw where any non-zero clock_id incorrectly fell back to monotonic time. Invalid IDs now properly fail with ORBIS_GEN2_ERROR_INVALID_ARGUMENT.

    Coalesced Single-Transaction Memory Writes:

    • Replaced consecutive isolated 8-byte scalar writes across POSIX clock_gettime, gettimeofday, and Orbis sceKernelClockGettime/sceKernelGettimeofday with safe single-transaction 16-byte stackalloc byte buffer writes via BinaryPrimitives and ctx.Memory.TryWrite. This entirely prevents partial memory state corruption on virtual page boundaries.
    • Implemented a single 8-byte coalesced zero-fill transaction for the deprecated/legacy timezone buffer (timezoneAddress != 0), aligning it with standard FreeBSD stub behavior.
    • Standardized POSIX failure path routines. Write faults cleanly issue TrySetErrno(ctx, Efault) while safely omitting explicit manual Rax writes, letting the import dispatcher natively sign-extend the return -1 value to 0xFFFFFFFFFFFFFFFF.

    Zero-Alloc Host RDTSC Execution Stub:

    • Patched CreateRdtscReader() to stream native architecture opcodes out of stack-allocated spans directly into host executable memory zones (VirtualAlloc) via unsafe { Buffer.MemoryCopy(...) }, completely removing the high-frequency .ToArray() runtime allocation overhead on the hot path.

    Files: KernelRuntimeCompatExports.cs, KernelMemoryCompatExports.cs

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