Fix bug in instanceof stub

If the instanceof stub was requested to deliver true/false objects as the result instead of 0/1 then 0/1 was actually returned if the builtin INSTANCE_OF ended up being called. This is now fixed.

BUG=v8:1020
TEST=test/mjsunit/regress/regress-1020.js
Review URL: http://codereview.chromium.org/6014013

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@6185 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

diff --git a/src/ia32/code-stubs-ia32.cc b/src/ia32/code-stubs-ia32.cc
index 93b211c..2b4a098 100644 (file)
--- a/src/ia32/code-stubs-ia32.cc
+++ b/src/ia32/code-stubs-ia32.cc
@@ -5164,14 +5164,31 @@ void InstanceofStub::Generate(MacroAssembler* masm) {
 
   // Slow-case: Go through the JavaScript implementation.
   __ bind(&slow);
-  if (HasArgsInRegisters()) {
-    // Push arguments below return address.
-    __ pop(scratch);
+  if (!ReturnTrueFalseObject()) {
+    // Tail call the builtin which returns 0 or 1.
+    if (HasArgsInRegisters()) {
+      // Push arguments below return address.
+      __ pop(scratch);
+      __ push(object);
+      __ push(function);
+      __ push(scratch);
+    }
+    __ InvokeBuiltin(Builtins::INSTANCE_OF, JUMP_FUNCTION);
+  } else {
+    // Call the builtin and convert 0/1 to true/false.
     __ push(object);
     __ push(function);
-    __ push(scratch);
+    __ InvokeBuiltin(Builtins::INSTANCE_OF, CALL_FUNCTION);
+    NearLabel true_value, done;
+    __ test(eax, Operand(eax));
+    __ j(zero, &true_value);
+    __ mov(eax, Factory::false_value());
+    __ jmp(&done);
+    __ bind(&true_value);
+    __ mov(eax, Factory::true_value());
+    __ bind(&done);
+    __ ret((HasArgsInRegisters() ? 0 : 2) * kPointerSize);
   }
-  __ InvokeBuiltin(Builtins::INSTANCE_OF, JUMP_FUNCTION);
 }
 
 

diff --git a/test/mjsunit/regress/regress-1020.js b/test/mjsunit/regress/regress-1020.js
new file mode 100644 (file)
index 0000000..307a61e
--- /dev/null
+++ b/test/mjsunit/regress/regress-1020.js
@@ -0,0 +1,32 @@
+// Copyright 2011 the V8 project authors. All rights reserved.
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+//       notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+//       copyright notice, this list of conditions and the following
+//       disclaimer in the documentation and/or other materials provided
+//       with the distribution.
+//     * Neither the name of Google Inc. nor the names of its
+//       contributors may be used to endorse or promote products derived
+//       from this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+function isObject(o) {
+  return o instanceof Object;
+}
+
+assertTrue(isObject(Object));