Fix safe calls codegen for nullable generic

compiler/backend/src/org/jetbrains/jet/codegen/ExpressionCodegen.java

@@ -2228,11 +2228,9 @@ public class ExpressionCodegen extends JetVisitor<StackValue, StackValue> implem
     @Override
     public StackValue visitSafeQualifiedExpression(JetSafeQualifiedExpression expression, StackValue receiver) {
         JetExpression expr = expression.getReceiverExpression();
-        JetType receiverJetType = bindingContext.get(BindingContext.EXPRESSION_TYPE, expression.getReceiverExpression());
-        assert receiverJetType != null;
-        Type receiverType = asmType(receiverJetType);
+        Type receiverType = expressionType(expr);
         gen(expr, receiverType);
-        if (!receiverJetType.isNullable()) {
+        if (isPrimitive(receiverType)) {
             StackValue propValue = genQualified(StackValue.onStack(receiverType), expression.getSelectorExpression());
             Type type = boxType(propValue.type);
             propValue.put(type, v);

compiler/testData/codegen/box/safeCall/genericNull.kt

@@ -0,0 +1,8 @@
+fun foo<T : Number?>(t: T) {
+    t?.toInt()
+}
+
+fun box(): String {
+    foo<Int?>(null)
+    return "OK"
+}

compiler/testData/codegen/box/safeCall/primitive.kt

@@ -0,0 +1,8 @@
+fun Int.foo() = 239
+fun Long.bar() = 239.toLong()
+
+fun box(): String {
+    42?.foo()
+    42.toLong()?.bar()
+    return "OK"
+}

compiler/tests/org/jetbrains/jet/codegen/generated/BlackBoxCodegenTestGenerated.java

@@ -3050,6 +3050,11 @@ public class BlackBoxCodegenTestGenerated extends AbstractBlackBoxCodegenTest {
             JetTestUtils.assertAllTestsPresentByMetadata(this.getClass(), "org.jetbrains.jet.generators.tests.GenerateTests", new File("compiler/testData/codegen/box/safeCall"), "kt", true);
         }
         
+        @TestMetadata("genericNull.kt")
+        public void testGenericNull() throws Exception {
+            blackBoxFileByFullPath("compiler/testData/codegen/box/safeCall/genericNull.kt");
+        }
+        
         @TestMetadata("kt1572.kt")
         public void testKt1572() throws Exception {
             blackBoxFileByFullPath("compiler/testData/codegen/box/safeCall/kt1572.kt");
@@ -3070,6 +3075,11 @@ public class BlackBoxCodegenTestGenerated extends AbstractBlackBoxCodegenTest {
             blackBoxFileByFullPath("compiler/testData/codegen/box/safeCall/kt247.kt");
         }
         
+        @TestMetadata("primitive.kt")
+        public void testPrimitive() throws Exception {
+            blackBoxFileByFullPath("compiler/testData/codegen/box/safeCall/primitive.kt");
+        }
+        
     }
     
     @TestMetadata("compiler/testData/codegen/box/strings")