In practice this is only needed after a return to a lower frame.
Record __call resolving and specialization for CALL* bytecodes. Record argument adjustment and fast functions for FUNC* bytecodes. Avoids all pending/immediate decisions for chained fast functions. Cleaner semantics for pcall(), xpcall() and __tostring metamethod. Prerequisite to drop the shadow frame link stack again.
Drop call gates. Use function headers, dispatched like bytecodes. Emit BC_FUNCF/BC_FUNCV bytecode at PC 0 for all Lua functions. C functions and ASM fast functions get extra bytecodes. Modify internal calling convention: new base in BASE (formerly in RA). Can now use better C function wrapper semantics (dynamic on/off). Prerequisite for call hooks with zero-overhead if disabled. Prerequisite for compiling recursive calls. Prerequisite for efficient 32/64 bit prototype guards.