KT-1055 wrong identityEquals codegen

compiler/backend/src/org/jetbrains/jet/codegen/intrinsics/Equals.java

@@ -21,10 +21,11 @@ import java.util.List;
 public class Equals implements IntrinsicMethod {
     @Override
     public StackValue generate(ExpressionCodegen codegen, InstructionAdapter v, Type expectedType, PsiElement element, List<JetExpression> arguments, StackValue receiver) {
-        receiver.put(JetTypeMapper.TYPE_OBJECT, v);
 
         boolean leftNullable = true;
+        JetExpression rightExpr;
         if(element instanceof JetCallExpression) {
+            receiver.put(JetTypeMapper.TYPE_OBJECT, v);
             JetCallExpression jetCallExpression = (JetCallExpression) element;
             JetExpression calleeExpression = jetCallExpression.getCalleeExpression();
             if(calleeExpression != null) {
@@ -32,9 +33,15 @@ public class Equals implements IntrinsicMethod {
                 if(leftType != null)
                     leftNullable = leftType.isNullable();
             }
+            rightExpr = arguments.get(0);
         }
-        
+        else {
-        JetExpression rightExpr = arguments.get(0);
+            JetExpression leftExpr = arguments.get(0);
+            leftNullable = codegen.getBindingContext().get(BindingContext.EXPRESSION_TYPE, leftExpr).isNullable();
+            codegen.gen(leftExpr).put(JetTypeMapper.TYPE_OBJECT, v);
+            rightExpr = arguments.get(1);
+        }
+
         JetType rightType = codegen.getBindingContext().get(BindingContext.EXPRESSION_TYPE, rightExpr);
         codegen.gen(rightExpr).put(JetTypeMapper.TYPE_OBJECT, v);
 

compiler/testData/codegen/regressions/kt1055.kt

@@ -0,0 +1,6 @@
+fun box() : String {
+    val a = "lala"
+    if(!a.identityEquals(a)) return "fail 1"
+    if(a identityEquals a) return "OK"
+    return "fail 2"
+}

compiler/tests/org/jetbrains/jet/codegen/PrimitiveTypesTest.java

@@ -391,4 +391,8 @@ public class PrimitiveTypesTest extends CodegenTestCase {
     public void testKt935 () {
         blackBoxFile("regressions/kt935.kt");
     }
+
+    public void testKt1055 () {
+        blackBoxFile("regressions/kt1055.kt");
+    }
 }