jack-compiler/compiler.c

#include <stdlib.h>
#include <string.h>
#include "compiler.h"

int countparameters(EXPRESSIONLIST* params) {
	int i = 0;
	while(params != NULL) {
		i++;
		params = params->next;
	}
	return i;
}

int countlocalvars(VARDEC* decs) {
	int i = 0;
	while(decs != NULL) {
		i++;
		decs = decs->next;
	}
	return i;
}

char* dotlabel(char* n1, char* n2) {
	int sz = (strlen(n1) + strlen(n2) + 2) * sizeof(char);
	char* result = (char*)malloc(sz);
	sprintf(result, "%s.%s", n1, n2);
	return result;
}

char* subdecname(CLASS* c, SUBDEC* sd) {
	return dotlabel(c->name, sd->name);
}

LINE* onetoken(char* str) {
	LINE* ln = mkline(1);
	addtoken(ln, ezheapstr(str));
	ln->next = NULL;
	return ln;
}

LINE* mksimpleln(char** tokens, int count) {
	LINE* ln = mkline(count);
	for(int i = 0; i < count; i++)
		addtoken(ln, ezheapstr(tokens[i]));
	return ln;
}

LINE* mathopln(char op) {
	if(op == '+')
		return onetoken("add");
	if(op == '-')
		return onetoken("sub");
	if(op == '=')
		return onetoken("eq");
	if(op == '>')
		return onetoken("gt");
	if(op == '<')
		return onetoken("lt");
	if(op == '|')
		return onetoken("or");
	if(op == '&')
		return onetoken("and");
	if(op == '/') {
		char* tokens[] = { "call", "Math.divide", "2" };
		return mksimpleln(tokens, sizeof(tokens) / sizeof(char*));
	}
	if(op == '*') {
		char* tokens[] = { "call", "Math.multiply", "2" };
		return mksimpleln(tokens, sizeof(tokens) / sizeof(char*));
	}
}

LINEBLOCK* compileexpression(SCOPE* s, TERM* e) {
	LINEBLOCK* myblk;
	LINEBLOCK* next = NULL;

	if(e->type == intconstant) {
		LINE* ln = mkline(3);
		addtoken(ln, ezheapstr("push"));
		addtoken(ln, ezheapstr("constant"));
		addtoken(ln, itoa(e->integer));
		ln->next = NULL;
		myblk = mklnblk(ln);
	}
	else if(e->type == unaryopterm) {
		myblk = compileexpression(s, e->expression);
		LINE* neg = onetoken("neg");
		appendln(myblk, neg);
	}
	else if(e->type == innerexpression) {
		myblk = compileexpression(s, e->expression);
	}
	else {
		fprintf(stderr, "Unsupported term yet %i\n", e->type);
		exit(1);
	}

	if(e->next != NULL) {
		next = compileexpression(s, e->next);
		LINE* op = mathopln(e->op);
		appendln(next, op);
		op->next = NULL;
		myblk = mergelnblks(myblk, next);
	}

	return myblk;
}

LINEBLOCK* compileparameters(SCOPE* s, EXPRESSIONLIST* params) {
	LINEBLOCK* head = NULL;
	while(params != NULL) {
		head = mergelnblks(head, compileexpression(s, params->expression));
		params = params->next;
	}
	return head;
}

LINEBLOCK* compilecallln(CLASS* c, SUBROUTCALL* call) {
	LINE* ln = mkline(3);

	addtoken(ln, ezheapstr("call"));

	if(call->parentname != NULL)
		addtoken(ln, dotlabel(call->parentname, call->name));
	else
		addtoken(ln, dotlabel(c->name, call->name));

	addtoken(ln, itoa(countparameters(call->parameters)));

	return mklnblk(ln);
}

// temporary ignore list for OS functions
char* ignoresubdecs[] = {
	"printInt", "void"
};
int ignorecount = sizeof(ignoresubdecs) / sizeof(char*);

LINEBLOCK* compilesubroutcall(SCOPE* s, CLASS* c, SUBROUTCALL* call) {
	LINEBLOCK* block = compilecallln(c, call);

	if(call->parameters != NULL)
		block = mergelnblks(compileparameters(s, call->parameters), block);

	// void functions always return 0
	// therefore must be thrown away

	// gambiarra
	char* type = NULL;
	for(int i = 0; i < ignorecount; i += 2) {
		if(!strcmp(call->name, ignoresubdecs[i])) {
			type = ignoresubdecs[i+1];
			break;
		}
	}
	if(type == NULL)
		type = getsubdecfromcall(s, call)->type;
	if(!strcmp(type, "void")) {
		char* tokens[] = { "pop", "temp", "0" };
		appendln(block, mksimpleln(tokens, sizeof(tokens) / sizeof(char*)));
	}

	return block;
}

LINEBLOCK* compileret(SCOPE* s, TERM* e) {
	LINE* ret = onetoken("return");
	LINEBLOCK* block = mklnblk(ret);

	// void subdecs return 0
	if(e == NULL) {
		char* tokens[] = { "push", "constant", "0" };
		appendlnbefore(block, mksimpleln(tokens, sizeof(tokens) / sizeof(char*)));
	} else
		block = mergelnblks(compileexpression(s, e), block);

	return block;
}

LINEBLOCK* compilestatement(SCOPE* s, CLASS* c, STATEMENT* st) {
	if(st->type == dostatement)
		return compilesubroutcall(s, c, st->dost);
	else if(st->type == returnstatement)
		return compileret(s, st->retst);
	else {
		fprintf(stderr, "UNSUPPORTED\n");
		exit(1);
	}
}

LINEBLOCK* compilestatements(SCOPE* s, CLASS* c, STATEMENT* sts) {
	LINEBLOCK* head = NULL;
	while(sts != NULL) {
		head = mergelnblks(head, compilestatement(s, c, sts));
		sts = sts->next;
	}
	return head;
}

LINEBLOCK* compilefunbody(SCOPE* s, CLASS* c, SUBROUTBODY* b) {
	// missing scope and vardecs handling
	LINEBLOCK* head = compilestatements(s, c, b->statements);
	return head;
}

LINEBLOCK* compilefundec(SCOPE* s, CLASS* c, SUBDEC* f) {
	LINE* label = mkline(3);
	addtoken(label, ezheapstr("function"));
	addtoken(label, subdecname(c, f));
	addtoken(label, itoa(countlocalvars(f->body->vardecs)));
	label->next = NULL;

	if(f->body->statements != NULL) {
		LINEBLOCK* body = compilefunbody(s, c, f->body);
		appendlnbefore(body, label);
		return body;
	}
	else
		return mklnblk(label);
}

LINEBLOCK* compilesubdec(SCOPE* s, CLASS* c, SUBDEC* sd) {
	// 'this' and arguments are pushed by caller
	// Must have a 'return' at the end
	// Label names must have class name too (see mapping)
	
	// types: method, function, constructor
	// must switch all of these
	if(sd->subroutclass == function)
		return compilefundec(s, c, sd);
}

LINEBLOCK* compileclass(COMPILER* c, CLASS* class) {
	SCOPE* topscope = mkscope(c->globalscope);
	addclassvardecs(topscope, class->vardecs);
	addsubdecs(topscope, class->subdecs);

	LINEBLOCK* output = NULL;
	SUBDEC* curr = class->subdecs;
	while(curr != NULL) {
		output = mergelnblks(output, compilesubdec(topscope, class, curr));
		curr = curr->next;
	}
	return output;
}

void compile(COMPILER* c) {
	LINEBLOCK* output = NULL;
	CLASS* curr = c->globalscope->classes;
	while(curr != NULL) {
		output = mergelnblks(output, compileclass(c, curr));
		curr = curr->next;
	}
	c->output = output;
}

COMPILER* mkcompiler(CLASS* classes) {
	COMPILER* c = (COMPILER*)malloc(sizeof(COMPILER));
	c->globalscope = mkscope(NULL);
	addclasses(c->globalscope, classes);
	return c;
}