shithub: scc

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Add shift operators

--- a/cc.h

+++ b/cc.h

@@ -219,7 +219,8 @@

 enum {

 	OCAST, OPTR, OADD, OARY, OSIZE, OMUL, OSUB,

-	OINC, ODEC, OPINC, OPDEC, ODIV, OMOD

+	OINC, ODEC, OPINC, OPDEC, ODIV, OMOD, OSHL,

+	OSHR

 };

 extern void

--- a/code.c

+++ b/code.c

@@ -15,7 +15,9 @@

 	[OSIZE] = "#",

 	[OPTR] = "@",

 	[OMOD] = "*",

-	[ODIV] = "/'"

+	[ODIV] = "/'",

+	[OSHL] = "l",

+	[OSHR]  = "r"

 };

 Node *

--- a/expr.c

+++ b/expr.c

@@ -49,6 +49,7 @@

 static Node *

 arithmetic(char op, Node *np1, Node *np2)

 {

+	char *err;

 	Node *naux;

 	Type *tp1, *tp2, *tp3;

 	uint8_t t1, t2, taux, lvalue = 0;

@@ -56,6 +57,9 @@

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

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

+	if ((op == OSHL || op == OSHR) && (t1 != INT || t2 != INT))

+		goto bad_shift;

+

 	switch (t1) {

 	case INT:

 		switch (t2) {

@@ -112,10 +116,16 @@

 	np1->b.lvalue = lvalue;

 	return np1;

+bad_shift:

+	err = "invalid operands to shift operator";

+	goto error;

 nocomplete:

-	error("invalid use of indefined type");

+	err = "invalid use of indefined type";

+	goto error;

 incorrect:

-	error("incorrect arithmetic operands");

+	err = "incorrect arithmetic operands";

+error:

+	error(err);

 }

 static Node *

@@ -283,6 +293,24 @@

 	}

 }

+static struct node *

+shift(void)

+{

+	register char op;

+	register Node *np;

+

+	np = add();

+	for (;;) {

+		switch (yytoken) {

+		case SHL: op = OSHL; break;

+		case SHR: op = OSHR; break;

+		default:  return np;

+		}

+		next();

+		np = arithmetic(op, np, add());

+	}

+}

+

 Node *

 expr(void)

 {

@@ -289,7 +317,7 @@

 	register Node *np;

 	do

-		np = add();

+		np = shift();

 	while (yytoken == ',');

 	return np;

 }