handle packed structure assignment

Reference: /n/atom/patch/applied2013/packasgn5c
Date: Tue Jun 18 20:44:20 CES 2013
Signed-off-by: quanstro@quanstro.net

--- /sys/src/cmd/5c/cgen.c	Tue Jun 18 20:43:52 2013
+++ /sys/src/cmd/5c/cgen.c	Tue Jun 18 20:43:52 2013
@@ -848,7 +848,7 @@
 	Node nod0, nod1, nod2, nod3, nod4, *l, *r;
 	Type *t;
 	long pc1;
-	int i, m, c, x;
+	int i, m, c;
 
 	if(n == Z || n->type == T)
 		return;
@@ -1060,11 +1060,7 @@
 		return;
 	}
 
-	x = w & SZ_LONG-1;
 	w /= SZ_LONG;
-	if(x)
-		warn(n, "packed assignment");
-	else
 	if(w <= 2) {
 		if(n->complex > nn->complex) {
 			reglpcgen(&nod1, n, 1);
@@ -1167,30 +1163,6 @@
 		c--;
 		i++;
 	} while (c>0);
-
-	if(x){
-		regalloc(&nod3, &regnode, Z);
-		nod1.xoffset += SZ_LONG*w;
-		nod2.xoffset += SZ_LONG*w;
-		nod1.type->etype = types[TUSHORT]->etype;
-		nod2.type->etype = types[TUSHORT]->etype;
-		for(; x >= SZ_SHORT; x -= SZ_SHORT){
-			gmove(&nod1, &nod3);
-			gmove(&nod3, &nod2);
-			nod1.xoffset += SZ_SHORT;
-			nod2.xoffset += SZ_SHORT;
-		}
-		nod1.type->etype = types[TUCHAR]->etype;
-		nod2.type->etype = types[TUCHAR]->etype;
-		for(; x >= SZ_CHAR; x -= SZ_CHAR){
-			gmove(&nod1, &nod3);
-			gmove(&nod3, &nod2);
-			nod1.xoffset += SZ_CHAR;
-			nod2.xoffset += SZ_CHAR;
-		}
-		regfree(&nod3);
-	}
-
 	regfree(&nod1);
 	regfree(&nod2);
 }