| ▲ | anematode 5 hours ago | |||||||||||||||||||||||||
Interesting. How does the trampoline work? I'm wondering whether we could further decrease the overhead of the switch on GCC/clang by marking the push function with `__attribute__((preserve_none))`. Then among GPRs we only need to save the base and stack pointers, and the callers will only save what they need to | ||||||||||||||||||||||||||
| ▲ | ambonvik 4 hours ago | parent [-] | |||||||||||||||||||||||||
It is an assembly function that does not get called from anywhere. I pre-load the stack image with its intended register content from C, including the trampoline function address as the "return address". On the first transfer to the newly created coroutine, that gets loaded, which in turn calls the coroutine function that suddenly is in one of its registers along with its arguments. If the coroutine function ever returns, that just continues the trampoline function, which proceeds to call the coroutine_exit() function, whose address also just happens to be stored in another handy register. https://github.com/ambonvik/cimba/blob/main/src/port/x86-64/... https://github.com/ambonvik/cimba/blob/main/src/port/x86-64/... | ||||||||||||||||||||||||||
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