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Mike Saito
5e76554514
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