From 99ecb82ce03e629bb25cc0ddd4b1261809a3cd0d Mon Sep 17 00:00:00 2001
From: Evgeny Gerashchenko <Evgeny.Gerashchenko@jetbrains.com>
Date: Tue, 5 Aug 2014 16:10:42 +0400
Subject: [PATCH] Simpler byte code generated for comparison with null and
 zero.

Analogous byte code is generated by Javac.
---
 .../jet/codegen/ExpressionCodegen.java        | 36 ++++++++++++-------
 1 file changed, 24 insertions(+), 12 deletions(-)

diff --git a/compiler/backend/src/org/jetbrains/jet/codegen/ExpressionCodegen.java b/compiler/backend/src/org/jetbrains/jet/codegen/ExpressionCodegen.java
index 9cf62c423df..aff50c829f3 100644
--- a/compiler/backend/src/org/jetbrains/jet/codegen/ExpressionCodegen.java
+++ b/compiler/backend/src/org/jetbrains/jet/codegen/ExpressionCodegen.java
@@ -2849,34 +2849,46 @@ public class ExpressionCodegen extends JetVisitor<StackValue, StackValue> implem
     }
 
     private StackValue genCmpWithZero(JetExpression exp, Type expType, IElementType opToken) {
-        v.iconst(1);
         gen(exp, expType);
-        Label ok = new Label();
+        Label trueLabel = new Label();
+        Label afterLabel = new Label();
         if (JetTokens.EQEQ == opToken || JetTokens.EQEQEQ == opToken) {
-            v.ifeq(ok);
+            v.ifeq(trueLabel);
         }
         else {
-            v.ifne(ok);
+            v.ifne(trueLabel);
         }
-        v.pop();
+
         v.iconst(0);
-        v.mark(ok);
+        v.goTo(afterLabel);
+
+        v.mark(trueLabel);
+        v.iconst(1);
+
+        v.mark(afterLabel);
+
         return StackValue.onStack(Type.BOOLEAN_TYPE);
     }
 
     private StackValue genCmpWithNull(JetExpression exp, Type expType, IElementType opToken) {
-        v.iconst(1);
         gen(exp, boxType(expType));
-        Label ok = new Label();
+        Label trueLabel = new Label();
+        Label afterLabel = new Label();
         if (JetTokens.EQEQ == opToken || JetTokens.EQEQEQ == opToken) {
-            v.ifnull(ok);
+            v.ifnull(trueLabel);
         }
         else {
-            v.ifnonnull(ok);
+            v.ifnonnull(trueLabel);
         }
-        v.pop();
+
         v.iconst(0);
-        v.mark(ok);
+        v.goTo(afterLabel);
+
+        v.mark(trueLabel);
+        v.iconst(1);
+
+        v.mark(afterLabel);
+
         return StackValue.onStack(Type.BOOLEAN_TYPE);
     }