Fixed type feedback in presence of negative lookups.

To fix the issue at hand regarding constant function calls and perhaps
other hidden issues regarding negative lookups, we basically add a
"marker instruction", just for harvesting purposes. Our type feedback
oracle is really, really fragile, we should better switch to some more
explicit and robust scheme soon.

BUG=chromium:252797
R=mstarzinger@chromium.org

Review URL: https://codereview.chromium.org/19588002

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@15741 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

diff --git a/src/arm/stub-cache-arm.cc b/src/arm/stub-cache-arm.cc
index 3bec1c5..d7b1b55 100644 (file)
--- a/src/arm/stub-cache-arm.cc
+++ b/src/arm/stub-cache-arm.cc
@@ -1185,6 +1185,10 @@ Register StubCompiler::CheckPrototypes(Handle<JSObject> object,
                                        int save_at_depth,
                                        Label* miss,
                                        PrototypeCheckType check) {
+  // Make sure that the type feedback oracle harvests the receiver map.
+  // TODO(svenpanne) Remove this hack when all ICs are reworked.
+  __ mov(scratch1, Operand(Handle<Map>(object->map())));
+
   Handle<JSObject> first = object;
   // Make sure there's no overlap between holder and object registers.
   ASSERT(!scratch1.is(object_reg) && !scratch1.is(holder_reg));

diff --git a/src/ia32/stub-cache-ia32.cc b/src/ia32/stub-cache-ia32.cc
index 6633375..2b391e0 100644 (file)
--- a/src/ia32/stub-cache-ia32.cc
+++ b/src/ia32/stub-cache-ia32.cc
@@ -1132,6 +1132,10 @@ Register StubCompiler::CheckPrototypes(Handle<JSObject> object,
                                        int save_at_depth,
                                        Label* miss,
                                        PrototypeCheckType check) {
+  // Make sure that the type feedback oracle harvests the receiver map.
+  // TODO(svenpanne) Remove this hack when all ICs are reworked.
+  __ mov(scratch1, Handle<Map>(object->map()));
+
   Handle<JSObject> first = object;
   // Make sure there's no overlap between holder and object registers.
   ASSERT(!scratch1.is(object_reg) && !scratch1.is(holder_reg));

diff --git a/src/mips/stub-cache-mips.cc b/src/mips/stub-cache-mips.cc
index b7ffb4f..89d8e68 100644 (file)
--- a/src/mips/stub-cache-mips.cc
+++ b/src/mips/stub-cache-mips.cc
@@ -1192,6 +1192,10 @@ Register StubCompiler::CheckPrototypes(Handle<JSObject> object,
                                        int save_at_depth,
                                        Label* miss,
                                        PrototypeCheckType check) {
+  // Make sure that the type feedback oracle harvests the receiver map.
+  // TODO(svenpanne) Remove this hack when all ICs are reworked.
+  __ li(scratch1, Operand(Handle<Map>(object->map())));
+
   Handle<JSObject> first = object;
   // Make sure there's no overlap between holder and object registers.
   ASSERT(!scratch1.is(object_reg) && !scratch1.is(holder_reg));

diff --git a/src/x64/stub-cache-x64.cc b/src/x64/stub-cache-x64.cc
index bde1d0b..a903ea1 100644 (file)
--- a/src/x64/stub-cache-x64.cc
+++ b/src/x64/stub-cache-x64.cc
@@ -1059,6 +1059,10 @@ Register StubCompiler::CheckPrototypes(Handle<JSObject> object,
                                        int save_at_depth,
                                        Label* miss,
                                        PrototypeCheckType check) {
+  // Make sure that the type feedback oracle harvests the receiver map.
+  // TODO(svenpanne) Remove this hack when all ICs are reworked.
+  __ Move(scratch1, Handle<Map>(object->map()));
+
   Handle<JSObject> first = object;
   // Make sure there's no overlap between holder and object registers.
   ASSERT(!scratch1.is(object_reg) && !scratch1.is(holder_reg));

diff --git a/test/mjsunit/regress/regress-252797.js b/test/mjsunit/regress/regress-252797.js
new file mode 100644 (file)
index 0000000..406be85
--- /dev/null
+++ b/test/mjsunit/regress/regress-252797.js
@@ -0,0 +1,57 @@
+// Copyright 2013 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.
+
+// Flags: --allow-natives-syntax
+
+// The type feedback oracle had a bug when retrieving the map from an IC
+// starting with a negative lookup.
+
+// Create a holder in fast mode.
+var holder = Object.create(null, {
+  holderMethod: {value: function() {}}
+});
+assertTrue(%HasFastProperties(holder));
+
+// Create a receiver into dictionary mode.
+var receiver = Object.create(holder, {
+  killMe: {value: 0, configurable: true},
+});
+delete receiver.killMe;
+assertFalse(%HasFastProperties(receiver));
+
+// The actual function to test, triggering the retrieval of the wrong map.
+function callConstantFunctionOnPrototype(obj) {
+  obj.holderMethod();
+}
+
+callConstantFunctionOnPrototype(receiver);
+callConstantFunctionOnPrototype(receiver);
+%OptimizeFunctionOnNextCall(callConstantFunctionOnPrototype);
+callConstantFunctionOnPrototype(receiver);
+
+// Make sure that the function is still optimized.
+assertTrue(2 != %GetOptimizationStatus(callConstantFunctionOnPrototype));