5.7.7.15 Function-cse Option
The -ffunction-cse
form of this option allows the address of called functions to
be held in registers. This is the default action if no option is specified.
The -fno-function-cse
form of this option will not place function
addresses in registers. Each instruction that calls a constant function contain the function's
address explicitly. This option results in less efficient code, but some strange hacks that
alter the assembler output may be confused by the optimizations performed when this option is
not used.