Nuke CompareToNull AST node.

src/ast.cc

Index: src/ast.cc
===================================================================
--- src/ast.cc	(revision 9281)
+++ src/ast.cc	(working copy)
@@ -380,6 +380,27 @@
 }
 
 
+bool CompareOperation::IsLiteralCompareNull(Expression** expr) {
+  if (op_ != Token::EQ && op_ != Token::EQ_STRICT) return false;
+
+  // Check for the pattern: <expression> equals null.
+  Literal* right_literal = right_->AsLiteral();
+  if (right_literal != NULL && right_literal->handle()->IsNull()) {
+    *expr = left_;
+    return true;
+  }
+
+  // Check for the pattern: null equals <expression>.
+  Literal* left_literal = left_->AsLiteral();
+  if (left_literal != NULL && left_literal->handle()->IsNull()) {
+    *expr = right_;
+    return true;
+  }
+
+  return false;
+}
+
+
 // ----------------------------------------------------------------------------
 // Inlining support
 
@@ -598,11 +619,6 @@
 }
 
 
-bool CompareToNull::IsInlineable() const {
-  return expression()->IsInlineable();
-}
-
-
 bool CountOperation::IsInlineable() const {
   return expression()->IsInlineable();
 }