Class description An instruction for calling a function in a dynamically linked library. It has the following slots:
dead-outputs
A sequence of return values from the function that the compiler.cfg.dce pass has figured out are not used.
reg-inputs
Registers to use for the arguments to the function call. Each sequence item is a 3-tuple consisting of a spill-slot, register representation and a register. When the function is called, the parameter is copied from the spill slot to the given register.
stack-inputs
Stack slots used for the arguments to the function call.
reg-outputs
If the called function returns a value, then this slot is a one-element sequence containing a 3-tuple describing which register is used for the return value.
If the invoked C function calls Factor code which triggers a GC, then a gc-map is necessary to find the roots.
Which function arguments that goes in reg-inputs and which goes in stack-inputs depend on the calling convention. In cdecl on x86.32, all arguments goes in stack-inputs, in x86.64 on unix, the first six arguments are passed in registers and then stack parameters are used for the remainder.