remove assignment cases from switch

R=r
OCL=26480
CL=26480

src/cmd/gc/swt.c

@@ -44,49 +44,15 @@ sw0(Node *c, Type *place, int arg)
 			return T;
 		}
 		walktype(c, Erv);
-		return T;
+		break;
 	case OTYPESW:
 		if(arg != Stype)
 			yyerror("inappropriate type case");
-		return T;
-	case OAS:
 		break;
-	}
-	walktype(c->left, Elv);
-
-	r = c->right;
-	if(c == N)
-		return T;
-
-	switch(r->op) {
-	default:
-		goto bad;
-	case ORECV:
-		// <-chan
-		walktype(r->left, Erv);
-		if(!istype(r->left->type, TCHAN))
-			goto bad;
-		break;
-	case OINDEX:
-		// map[e]
-		walktype(r->left, Erv);
-		if(!istype(r->left->type, TMAP))
-			goto bad;
-		break;
-	case ODOTTYPE:
-		// interface.(type)
-		walktype(r->left, Erv);
-		if(!istype(r->left->type, TINTER))
-			goto bad;
+	case OAS:
+		yyerror("inappropriate assignment in a case statement");
 		break;
 	}
-	c->type = types[TBOOL];
-	if(arg != Strue)
-		goto bad;
-	return T;
-
-bad:
-	yyerror("inappropriate assignment in a case statement");
 	return T;
 }
 
@@ -311,26 +277,6 @@ loop:
 		t->ninit = N;
 	}
 
-	if(t->left->op == OAS) {
-		if(bool == N) {
-			bool = nod(OXXX, N, N);
-			tempname(bool, types[TBOOL]);
-		}
-		t->left->left = nod(OLIST, t->left->left, bool);
-		cas = list(cas, t->left);		// v,bool = rhs
-
-		a = nod(OIF, N, N);
-		a->nbody = t->right;			// then goto l
-		a->ntest = bool;
-		if(arg != Strue)
-			a->ntest = nod(ONOT, bool, N);
-		cas = list(cas, a);			// if bool goto l
-
-		t = listnext(&save);
-		goto loop;
-	}
-
-
 	switch(arg) {
 	default:
 		// not bool const

test/typeswitch.go

@@ -62,30 +62,30 @@ func f(i int) interface{} {
 
 func main() {
 	// type guard style
-	for i := Bool; i < Last; i++ {
-		switch v := f(i); true {
-		case x := v.(bool):
-			assert(x == true && i == Bool, "switch 1 bool");
-		case x := v.(int):
-			assert(x == 7 && i == Int, "switch 1 int");
-		case x := v.(float):
-			assert(x == 7.4 && i == Float, "switch 1 float");
-		case x := v.(string):
-			assert(x == "hello" && i == String, "switch 1 string");
-		case x := v.(S):
-			assert(x.a == 1234 && i == Struct, "switch 1 struct");
-		case x := v.(chan int):
-			assert(x == c && i == Chan, "switch 1 chan");
-		case x := v.([]int):
-			assert(x[3] == 3 && i == Array, "switch 1 array");
-		case x := v.(map[string]int):
-			assert(x == m && i == Map, "switch 1 map");
-		case x := v.(func(i int) interface{}):
-			assert(x == f && i == Func, "switch 1 fun");
-		default:
-			assert(false, "switch 1 unknown");
-		}
-	}
+//	for i := Bool; i < Last; i++ {
+//		switch v := f(i); true {
+//		case x := v.(bool):
+//			assert(x == true && i == Bool, "switch 1 bool");
+//		case x := v.(int):
+//			assert(x == 7 && i == Int, "switch 1 int");
+//		case x := v.(float):
+//			assert(x == 7.4 && i == Float, "switch 1 float");
+//		case x := v.(string):
+//			assert(x == "hello" && i == String, "switch 1 string");
+//		case x := v.(S):
+//			assert(x.a == 1234 && i == Struct, "switch 1 struct");
+//		case x := v.(chan int):
+//			assert(x == c && i == Chan, "switch 1 chan");
+//		case x := v.([]int):
+//			assert(x[3] == 3 && i == Array, "switch 1 array");
+//		case x := v.(map[string]int):
+//			assert(x == m && i == Map, "switch 1 map");
+//		case x := v.(func(i int) interface{}):
+//			assert(x == f && i == Func, "switch 1 fun");
+//		default:
+//			assert(false, "switch 1 unknown");
+//		}
+//	}
 
 	// type switch style
 	for i := Bool; i < Last; i++ {
@@ -135,24 +135,24 @@ func main() {
 		assert(false, "switch 4 unknown");
 	}
 
-	switch true {
-	case x := f(Int).(float):
-		assert(false, "switch 5 type guard wrong type");
-	case x := f(Int).(int):
-		assert(x == 7, "switch 5 type guard");
-	default:
-		assert(false, "switch 5 unknown");
-	}
+//	switch true {
+//	case x := f(Int).(float):
+//		assert(false, "switch 5 type guard wrong type");
+//	case x := f(Int).(int):
+//		assert(x == 7, "switch 5 type guard");
+//	default:
+//		assert(false, "switch 5 unknown");
+//	}
 
 	m["7"] = 7;
-	switch true {
-	case x := m["6"]:
-		assert(false, "switch 6 map reference wrong");
-	case x := m["7"]:
-		assert(x == 7, "switch 6 map reference");
-	default:
-		assert(false, "switch 6 unknown");
-	}
+//	switch true {
+//	case x := m["6"]:
+//		assert(false, "switch 6 map reference wrong");
+//	case x := m["7"]:
+//		assert(x == 7, "switch 6 map reference");
+//	default:
+//		assert(false, "switch 6 unknown");
+//	}
 
 	go func() { <-c; c <- 77; } ();
 	// guarantee the channel is ready
@@ -161,13 +161,13 @@ func main() {
 		sys.Gosched();
 	}
 	dummyc := make(chan int);
-	switch true {
-	case x := <-dummyc:
-		assert(false, "switch 7 chan wrong");
-	case x := <-c:
-		assert(x == 77, "switch 7 chan");
-	default:
-		assert(false, "switch 7 unknown");
-	}
+//	switch true {
+//	case x := <-dummyc:
+//		assert(false, "switch 7 chan wrong");
+//	case x := <-c:
+//		assert(x == 77, "switch 7 chan");
+//	default:
+//		assert(false, "switch 7 unknown");
+//	}
 
 }