Ref makeSysFn( CodeGen codegen, std::string fn_name, Ref default_value ) {
SysMap::iterator smit = SysMap::systemFunctionsMap().find( fn_name );
if ( smit == SysMap::systemFunctionsMap().end() ) {
return default_value;
}
SysInfo & info = smit->second;
Ref x = info.coreFunctionObject;
if ( x != NULL ) return x;
codegen->vmiFUNCTION( fn_name, info.in_arity.count(), info.out_arity.count() );
// We have two different kinds of system functions. Those that are
// implemented as native instructions and those that are implemented
// by hand-written functions.
//
// The test that distinguishes them is unsatisfactory because it fails
// to distinguish an omitted something from a genuine choice.
// REFACTOR.
//
if ( info.isSysCall() ) {
// Hand-written function.
codegen->vmiSYS_CALL( info.syscall );
} else if ( info.isVMOp() ) {
// Native instruction.
codegen->vmiINSTRUCTION( info.instruction );
} else {
throw SystemError( "Internal error" );
}
codegen->vmiSYS_RETURN();
Ref r = codegen->vmiENDFUNCTION( false );
info.coreFunctionObject = r;
return r;
}
