fix: restore original function bytes on x86_64 when mock is dropped#123
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mazong1123 wants to merge 1 commit intomainfrom
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fix: restore original function bytes on x86_64 when mock is dropped#123mazong1123 wants to merge 1 commit intomainfrom
mazong1123 wants to merge 1 commit intomainfrom
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When a ThreadRegistration is dropped and ref_count reaches 0, restore the original function bytes, free the JIT dispatcher and trampoline memory, and remove the registry entry. This eliminates the permanent dispatcher overhead for unmocked functions. Previously, after a mock was dropped, the JIT dispatcher remained installed at the function's entry point. While functionally correct (the dispatcher returned the original behavior via a trampoline), this caused stack overflow in downstream projects when running 500+ tests sequentially. Deep call chains through previously-patched functions accumulated dispatcher overhead (get_thread_target + catch_unwind + TLS lookup per call) that exceeded the default stack. The restoration is gated behind cfg(target_arch = "x86_64") since the ARM64/ARM32 concern about asynchronous instruction cache invalidation does not apply to x86_64's coherent instruction cache. Includes regression tests that verify: - Function machine code bytes are restored after mock is dropped - Repeated patch/drop cycles work correctly (registry cleanup) - Function behavior is correct across the mock lifecycle Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
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When a ThreadRegistration is dropped and ref_count reaches 0, restore the original function bytes, free the JIT dispatcher and trampoline memory, and remove the registry entry. This eliminates the permanent dispatcher overhead for unmocked functions.
Previously, after a mock was dropped, the JIT dispatcher remained installed at the function's entry point. While functionally correct (the dispatcher returned the original behavior via a trampoline), this caused stack overflow in downstream projects when running 500+ tests sequentially. Deep call chains through previously-patched functions accumulated dispatcher overhead (get_thread_target + catch_unwind + TLS lookup per call) that exceeded the default stack.
The restoration is gated behind cfg(target_arch = "x86_64") since the ARM64/ARM32 concern about asynchronous instruction cache invalidation does not apply to x86_64's coherent instruction cache.
Includes regression tests that verify: