ref: f0bad0d420fc126fa86c3e8a95f1783cc7032ed6
parent: 3f1579403feed901243196776461d5f02035fac7
author: Roberto E. Vargas Caballero <[email protected]>
date: Fri Apr 11 15:01:24 EDT 2014
Add ternary operator
--- a/cc.h
+++ b/cc.h
@@ -235,7 +235,8 @@
*unarycode(char op, Type *tp, Node *child),
*bincode(char op, Type *tp, Node *np1, Node *np2),
*castcode(Node *child, Type *tp),
- *sizeofcode(Type *tp);
+ *sizeofcode(Type *tp),
+ *ternarycode(Node *cond, Node *ifyes, Node *ifno);
#define SYM(s) ((union unode) {.sym = s}) #define OP(s) ((union unode) {.op = s})--- a/code.c
+++ b/code.c
@@ -104,6 +104,20 @@
}
void
+emitternary(Node *np)
+{+ Node *cond, *ifyes, *ifno;
+
+ cond = np->childs[0];
+ ifyes = np->childs[1];
+ ifno = np->childs[2];
+ (*cond->code)(cond);
+ (*ifyes->code)(ifyes);
+ (*ifno->code)(ifno);
+ printf("\t?%c", np->type->letter);+}
+
+void
emitsizeof(Node *np)
{ printf("\t#%c", np->u.type->letter);@@ -164,4 +178,14 @@
sizeofcode(Type *tp)
{return node(emitsizeof, inttype, TYP(tp), 0);
-}
\ No newline at end of file
+}
+
+Node *
+ternarycode(Node *cond, Node *ifyes, Node *ifno)
+{+ Node *np= node(emitternary, ifyes->type, OP(0), 3);
+ np->childs[0] = cond;
+ np->childs[1] = ifyes;
+ np->childs[2] = ifno;
+ return np;
+}
--- a/expr.c
+++ b/expr.c
@@ -445,9 +445,25 @@
}
static Node *
+ternary(void)
+{+ register Node *cond, *ifyes, *ifno;
+
+ cond = bit_or();
+ while (accept('?')) {+ ifyes = expr();
+ expect(':');+ ifno = expr();
+ /* TODO: check the types of ifno and ifyes */
+ cond = ternarycode(cond, ifyes, ifno);
+ }
+ return cond;
+}
+
+static Node *
assign(void)
{- register Node *np1 = bit_or(), *np2;
+ register Node *np1 = ternary(), *np2;
char *err;
for (;;) {@@ -471,6 +487,7 @@
np2 = assign();
if (!np1->b.lvalue)
goto nolvalue;
+ /* TODO: if it necessary a 0 comparision? */
if ((np2 = convert(np1, np2)) == NULL)
goto incompatibles;
np1 = bincode(op, np1->type, np1, np2);