/** NB! Must be called in correct order! */
public void addArg(String name, PhantomType type) throws PlcException {
if (type == null) {
// Object a = null; a.getClass();
throw new PlcException("Method add_arg", "null type of arg", name);
}
args_def.add(new ArgDefinition(name, type));
svars.add_stack_var(new PhantomVariable(name, type));
}
public void generate_code(CodeGeneratorState s) throws PlcException, IOException {
if (code == null) {
c.emitRet(); // empty function code
return;
}
// ------------------------------------------
// traverse tree to allocate automatic vars?
// ------------------------------------------
int n_auto_vars = svars.getUsedSlots();
int n_int_auto_vars = isvars.getUsedSlots();
// ------------------------------------------
// ------------------------------------------
// generate prologue code here
// ------------------------------------------
// check number of args
int n_args = args_def.size();
String good_args_label = c.getLabel();
c.emitIConst_32bit(n_args);
c.emitISubLU();
c.emitJz(good_args_label);
// wrong count - throw string
// BUG! Need less consuming way of reporting this. Maybe by
// calling class object Method? Or by summoning something?
c.emitString("arg count: " + name + " in " + s.get_class().getName());
c.emitThrow();
c.markLabel(good_args_label);
if (requestDebug) c.emitDebug((byte) 0x1, "Enabled debug");
// push nulls to reserve stack space for autovars
// BUG! We can execute vars initialization code here, can we?
// We can if code does not depend on auto vars itself, or depends only on
// previous ones.
// TODO: BUG! autovars in arguments are already on stack, we don't have to reserve space
for (int i = n_auto_vars; i > 0; i--) c.emitPushNull();
// TODO introduce instruction to reserve o+i space in one step
// Reserve integer stack place for int vars
for (int i = n_int_auto_vars; i > 0; i--) c.emitIConst_0();
// ------------------------------------------
// ------------------------------------------
// generate main code by descending the tree
// ------------------------------------------
code.generate_code(c, s);
// ------------------------------------------
// ------------------------------------------
// generate epilogue code here
// ------------------------------------------
if (requestDebug) c.emitDebug((byte) 0x2, "Disabled debug");
c.emitRet(); // catch the fall-out
// ------------------------------------------
}