shithub: scc

Info  •  Files  •  Log  •  Branches

Force to have a comparision in conditions

It is important for the code generator to have always
a comparision in the conditions, because it means that
the flag is set with the comparision. If the code
generator receives a constant it has to convert the
constant in a flag.

--- a/cc1/cc1.h

+++ b/cc1/cc1.h

@@ -346,7 +346,7 @@

 /* expr.c */

 extern Node *expr(void), *negate(Node *np), *constexpr(void);

 extern Node *convert(Node *np, Type *tp1, char iscast);

-extern Node *iszero(Node *np), *eval(Node *np), *iconstexpr(void);

+extern Node *eval(Node *np), *iconstexpr(void), *condition(void);

 /* cpp.c */

 extern void icpp(void);

--- a/cc1/expr.c

+++ b/cc1/expr.c

@@ -556,6 +556,7 @@

 	case OGE:  op = OLT;  break;

 	case OLE:  op = OGT;  break;

 	case OGT:  op = OLE;  break;

+	default:   return np;

 	}

 	np->op = op;

 	return np;

@@ -617,14 +618,6 @@

 	return lp;

 }

-Node *

-iszero(Node *np)

-{

-	if (isnodecmp(np->op))

-		return np;

-	return compare(ONE, np, constnode(zero));

-}

-

 static Node *

 assignop(char op, Node *lp, Node *rp)

 {

@@ -1158,4 +1151,18 @@

 	}

 	return lp;

+}

+

+Node *

+condition(void)

+{

+	Node *np;

+

+	expect('(');

+	np = exp2cond(expr(), 0);

+	if (np->constant)

+		np = node(ONE, inttype, np, constnode(zero));

+	expect(')');

+

+	return np;

 }

--- a/cc1/stmt.c

+++ b/cc1/stmt.c

@@ -54,23 +54,6 @@

 	expect(';');

 }

-static Node *

-condition(void)

-{

-	extern jmp_buf recover;

-	Node *np;

-

-	expect('(');

-	setsafe(END_COND);

-	if (!setjmp(recover))

-		np = expr();

-	else

-		np = constnode(zero);

-	np = iszero(np);

-	expect(')');

-	return np;

-}

-

 static void

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

 {