[Shared Everything] struct.wait on unshared should trap (#8498)

Author: kripken

src/wasm-interpreter.h

@@ -2254,6 +2254,10 @@ class ExpressionRunner : public OverriddenVisitor<SubType, Flow> {
     VISIT(expected, curr->expected)
     VISIT(timeout, curr->timeout)
 
+    if (!curr->ref->type.getHeapType().isShared()) {
+      trap("cannot struct.wait a non-shared object");
+    }
+
     auto data = ref.getSingleValue().getGCData();
     if (!data) {
       trap("null ref");

test/spec/waitqueue.wast

@@ -76,7 +76,7 @@
 )
 
 (module
-  (type $t (struct (field (mut waitqueue))))
+  (type $t (shared (struct (field (mut waitqueue)))))
 
   (global $g (mut (ref null $t)) (struct.new $t (i32.const 0)))
 
@@ -117,3 +117,16 @@
 
 (assert_trap (invoke "struct.wait" (i32.const 0) (i64.const 0)) "null ref")
 (assert_trap (invoke "struct.notify" (i32.const 0)) "null ref")
+
+;; Waiting on a non-shared struct should trap.
+(module
+  (type $t (struct (field (mut waitqueue))))
+
+  (global $g (mut (ref null $t)) (struct.new $t (i32.const 0)))
+
+  (func (export "struct.wait") (param $expected i32) (param $timeout i64) (result i32)
+    (struct.wait $t 0 (global.get $g) (local.get $expected) (local.get $timeout))
+  )
+)
+(assert_trap (invoke "struct.wait" (i32.const 0) (i64.const 100)) "not shared")
+