Georg-Johann Lay wrote: > The trouble is this: If a callee gets some arguments passed on the stack > or in call-saved regs, the callee is not ok for a sibling call. That's > because sibcall_epilogue executes before sibcall insns. > > All this information is pretty easy available in FUNCTION_ARGS resp. > FUNCTION_ARG_ADVANCE and can be stored in CUMULATIVE_ARGS. > > However, the place where the information is needed is in > targetm.function_ok_for_sibcall (aka. TARGET_FUNCTION_OK_FOR_SIBCALL), > and that hook only gets the function decl and call expression trees, but > these trees do not contain information about where the calle's arguments > get passed. > > How can that be fixed? Most probably, I am missing something, and the > information is hidden somewhere is the trees passed to > targetm.function_ok_for_sibcall?
> So what am I missing here? Is there some other approach to solve this? The standard answer is that frame layout and other per-function info is stored in the "struct function" machine-dependent part of the global 'cfun' current function struct. See: http://gcc.gnu.org/onlinedocs/gccint/Per_002dFunction-Data.html cheers, DaveK
