shithub: scc

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Emit code for arrays

This code generates a first version of how the code for arrays is
generated.

--- a/cc.h

+++ b/cc.h

@@ -215,11 +215,14 @@

 	OCAST, OPTR, OADD, OARY

 };

-extern void emitsym(Node *), emitunary(Node *), emitbin(Node *);

+extern void

+	emitsym(Node *), emitunary(Node *),

+	emitbin(Node *), emitexp(Node *);

+

 extern Node

 	*node(Inst code, Type *tp, union unode u, uint8_t nchilds),

 	*unarycode(char op, Type *tp, Node *child),

-	*bincode(char op, Node *np1, Node *np2);

+	*bincode(char op, Type *tp, Node *np1, Node *np2);

 #define SYM(s) ((union unode) {.sym = s})

 #define OP(s) ((union unode) {.op = s})

--- a/code.c

+++ b/code.c

@@ -4,6 +4,12 @@

 #include "cc.h"

+char *opcodes[] = {

+	[OADD] = "+",

+	[OARY] = "'",

+	[OPTR] = "@"

+};

+

 Node *

 node(Inst code, Type *tp, union unode u, uint8_t nchilds)

 {

@@ -25,9 +31,9 @@

 }

 Node *

-bincode(char op, Node *np1, Node *np2)

+bincode(char op, Type *tp, Node *np1, Node *np2)

 {

-	Node *np = node(emitbin, np1->type, OP(op), 2);

+	Node *np = node(emitbin, tp, OP(op), 2);

 	np->childs[0] = np1;

 	np->childs[1] = np2;

 	return np;

@@ -44,7 +50,7 @@

 	else if (sym->s.isstatic)

 		c = 'T';

 	else if (sym->s.isregister)

-		c = 'R';

+		c = 'Q';

 	else

 		c = 'A';

 	printf("\t%c%d", c, sym->id);

@@ -53,11 +59,42 @@

 void

 emitunary(Node *np)

 {

+	Node *child;

+	char op, letter;

+

+	letter = np->type->letter;

+	child = np->childs[0];

+	(*child->code)(child);

+	switch (op = np->u.op) {

+	case OCAST:

+		printf("\t%c%c", child->type->letter, letter);

+		break;

+	case OARY:

+		fputs("\t'", stdout);

+		break;

+	default:

+		printf("\t%s%c", opcodes[op], letter);

+		break;

+	}

 }

 void

 emitbin(Node *np)

 {

+	Node *child1, *child2;

+

+	child1 = np->childs[0];

+	child2 = np->childs[1];

+	(*child1->code)(child1);

+	(*child2->code)(child2);

+	printf("\t%s%c", opcodes[np->u.op], np->type->letter);

+}

+

+void

+emitexp(Node *np)

+{

+	(*np->code)(np);

+	putchar('\n');

 }

 void

--- a/expr.c

+++ b/expr.c

@@ -52,7 +52,7 @@

 	Type *tp1, *tp2;

 	uint8_t t1, t2, taux;

-	tp1 = UNQUAL(np1->type), tp2 = UNQUAL(np1->type);

+	tp1 = UNQUAL(np1->type), tp2 = UNQUAL(np2->type);

 	t1 = tp1->op, t2 = tp2->op;

 	switch (t1) {

@@ -87,17 +87,17 @@

 		}

 		break;

 	case PTR: case FTN: case ARY:

-pointer:	if (t1 == PTR)

-			np1 = unarycode(OPTR, np1->type, np1);

+pointer:	if (t1 == ARY)

+			tp1 = mktype(tp1->type, PTR, NULL, 0);

 		if (t2 != INT)

 			goto incorrect;

-		np2 = unarycode(OCAST, np1->type, np2);

+		np2 = unarycode(OCAST, tp1, np2);

 		break;

 	default:

 		goto incorrect;

 	}

-	return bincode(OADD, np1, np2);

+	return bincode(OADD, tp1, np1, np2);

 incorrect:

 	error("incorrect arithmetic operands"); /*TODO: print type names */

@@ -117,7 +117,7 @@

 	if (t1 != INT && t2 != INT)

 		goto bad_subs;

 	np1 = add(np1, np2);

-	return unarycode(OARY, UNQUAL(np1->type)->type , np1);

+	return unarycode(OARY, np1->type->type , np1);

 bad_vector:

 	err = "subscripted value is neither array nor pointer nor vector";

--- a/stmt.c

+++ b/stmt.c

@@ -8,6 +8,7 @@

 compound(void)

 {

 	extern void decl(void);

+	extern Node *expr(void);

 	expect('{');

 	while (!accept('}')) {

@@ -16,9 +17,8 @@

 			decl();

 			break;

 		default:

-			expr();

-			/* TODO: Evaluate the expression here */

+			emitexp(expr());

 		}

 		expect(';');

 	}

-}

\ No newline at end of file

+}