shithub: scc

Info  •  Files  •  Log  •  Branches

Merge common code in assign and incdec

This functions must check if the left value is a correct one, so
this part is common to them, so the best option is to create
a new function.

--- a/cc1/expr.c

+++ b/cc1/expr.c

@@ -58,6 +58,17 @@

 	*p2 = np2;

 }

+static void

+chklvalue(Node *np, Type *tp)

+{

+	if (!np->b.lvalue)

+		error("lvalue required in operation");

+	if (np->utype == voidtype)

+		error("invalid use of void expression");

+	if (isconst(tp->op))

+		error("const value modified");

+}

+

 Node *

 eval(Node *np)

 {

@@ -341,12 +352,7 @@

 {

 	Type *tp = np->utype;

-	if (!np->b.lvalue)

-		error("lvalue required in operation");

-	if (np->utype == voidtype)

-		error("invalid use of void expression");

-	if (isconst(tp->op))

-		error("const value modified");

+	chklvalue(np, np->utype);

 	switch (np->typeop) {

 	case PTR:

@@ -533,7 +539,7 @@

 		switch (yytoken) {

 		case '*': op = OMUL; fun = arithmetic; break;

 		case '/': op = ODIV; fun = arithmetic; break;

-		case '%': op = OMOD; fun = integerop;   break;

+		case '%': op = OMOD; fun = integerop;  break;

 		default: return np;

 		}

 		next();

@@ -708,12 +714,7 @@

 		case OR_EQ:  op = OA_OR;   fun = integerop;  break;

 		default: return np;

 		}

-		if (!np->b.lvalue)

-			error("lvalue required as left operand of assignment");

-		if (np->utype == voidtype)

-			error("invalid use of void expression");

-		if (isconst(np->type->op))

-			error("const value modified");

+		chklvalue(np, np->type);

 		next();

 		np = (fun)(op, np, eval(assign()));

 	}

--- a/cc1/stmt.c

+++ b/cc1/stmt.c

@@ -29,16 +29,12 @@

 {

 	Symbol *sym;

-	if (s) {

-		if ((sym = lookup(s, NS_LABEL)) != NULL) {

-			if (define && sym->s.isdefined)

-				error("label '%s' already defined", s);

-			else

-				sym->s.isdefined = 1;

-			return sym;

-		}

-	} else {

-		s = "";

+	if ((sym = lookup(s, NS_LABEL)) != NULL) {

+		if (define && sym->s.isdefined)

+			error("label '%s' already defined", s);

+		else

+			sym->s.isdefined = 1;

+		return sym;

 	}

 	sym = install(s, NS_LABEL);

@@ -72,9 +68,9 @@

 	Symbol *begin, *cond, *end;

 	Node *np;

-	begin = label(NULL, 1);

-	end = label(NULL, 1);

-	cond = label(NULL, 1);

+	begin = label("", 1);

+	end = label("", 1);

+	cond = label("", 1);

 	expect(WHILE);

 	np = condition();

@@ -94,9 +90,9 @@

 	Symbol *begin, *cond, *end;

 	Node *econd = NULL, *einc = NULL;

-	begin = label(NULL, 1);

-	end = label(NULL, 1);

-	cond = label(NULL, 1);

+	begin = label("", 1);

+	end = label("", 1);

+	cond = label("", 1);

 	expect(FOR);

 	expect('(');

@@ -124,9 +120,8 @@

 static void

 Dowhile(Caselist *lswitch)

 {

-	Symbol *begin= label(NULL, 1), *end = label(NULL, 1);

+	Symbol *begin = label("", 1), *end = label("", 1);

-

 	expect(DO);

 	emitbloop();

 	emitlabel(begin);

@@ -206,7 +201,7 @@

 {

 	Caselist lcase = {.nr = 0, .head = NULL, .deflabel = NULL};

 	struct scase *p;

-	Symbol *lbreak = label(NULL, 1), *lcond = label(NULL, 1);

+	Symbol *lbreak = label("", 1), *lcond = label("", 1);

 	Node *cond;

 	expect(SWITCH);

@@ -230,7 +225,7 @@

 Case(Symbol *lbreak, Symbol *lcont, Caselist *lswitch)

 {

 	Node *np;

-	Symbol *lcase = label(NULL, 1);

+	Symbol *lcase = label("", 1);

 	struct scase *pcase;

 	if (!lswitch)

@@ -253,7 +248,7 @@

 static void

 Default(Symbol *lbreak, Symbol *lcont, Caselist *lswitch)

 {

-	Symbol *ldefault = label(NULL, 1);

+	Symbol *ldefault = label("", 1);

 	expect(DEFAULT);

 	expect(':');

@@ -264,7 +259,7 @@

 static void

 If(Symbol *lbreak, Symbol *lcont, Caselist *lswitch)

 {

-	Symbol *end, *lelse = label(NULL, 1);

+	Symbol *end, *lelse = label("", 1);

 	Node *np;

 	expect(IF);

@@ -273,7 +268,7 @@

 	emitjump(lelse, np);

 	stmt(lbreak, lcont, lswitch);

 	if (accept(ELSE)) {

-		end = label(NULL, 1);

+		end = label("", 1);

 		emitjump(end, NULL);

 		emitlabel(lelse);

 		stmt(lbreak, lcont, lswitch);