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3.4.6 Per Function Execution Context

A function specific data set may be supplied to the method implementing the function logic as its first argument.

To indicate that such provision should be made, the function definition must include the X1f4_E4_TEXT_LINK bit in its flags field.

See Function Flags.

Whenever the expression parser picks up a reference to a function requiring a specific execution context it calls the function_set.fix method of the struct x1f4_e4_type expression parsing context, immediately after the function_set.get call that looked up the function. The function_set.fix method is supplied the function lookup context as first argument (the function_set.context field in the parsing context) and the function definition as the second (as retrieved via the immediately preceding function_set.get call). The function_set.fix method is expected to set the context reference (void pointer, that is) for which a reference is passed as the third argument to the function specific execution context.

See struct x1f4_e4_type.

The function_set.fix method in the struct x1f4_e4_type expression parsing context is used only to retrieve the function specific execution contexts and only for functions requiring specific execution contexts (and marked by the X1f4_E4_TEXT_LINK bit in their flags field defitions).

Assuming ‘method13’ implementing the logic of some function having a specific execution context, the function specific execution context can be accessed context:

method13(void *context, void *output, void **input)
    -context- is the function specific context