Turn Runtime_MigrateInstance into Runtime_TryMigrateInstance

because it must not cause lazy deopts because it is called from deferred code that cannot handle lazy deopts.

Hat tip to Ben for doing most of the debugging work, and to Toon for writing the regression test.

BUG=chromium:315252
LOG=Y
R=verwaest@chromium.org

Review URL: https://codereview.chromium.org/131243003

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@18586 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
parent 1ab6727b
......@@ -5184,7 +5184,7 @@ void LCodeGen::DoDeferredInstanceMigration(LCheckMaps* instr, Register object) {
PushSafepointRegistersScope scope(this, Safepoint::kWithRegisters);
__ push(object);
__ mov(cp, Operand::Zero());
__ CallRuntimeSaveDoubles(Runtime::kMigrateInstance);
__ CallRuntimeSaveDoubles(Runtime::kTryMigrateInstance);
RecordSafepointWithRegisters(
instr->pointer_map(), 1, Safepoint::kNoLazyDeopt);
__ StoreToSafepointRegisterSlot(r0, scratch0());
......
......@@ -5605,7 +5605,7 @@ void LCodeGen::DoDeferredInstanceMigration(LCheckMaps* instr, Register object) {
PushSafepointRegistersScope scope(this);
__ push(object);
__ xor_(esi, esi);
__ CallRuntimeSaveDoubles(Runtime::kMigrateInstance);
__ CallRuntimeSaveDoubles(Runtime::kTryMigrateInstance);
RecordSafepointWithRegisters(
instr->pointer_map(), 1, Safepoint::kNoLazyDeopt);
......
......@@ -5127,7 +5127,7 @@ void LCodeGen::DoDeferredInstanceMigration(LCheckMaps* instr, Register object) {
PushSafepointRegistersScope scope(this, Safepoint::kWithRegisters);
__ push(object);
__ mov(cp, zero_reg);
__ CallRuntimeSaveDoubles(Runtime::kMigrateInstance);
__ CallRuntimeSaveDoubles(Runtime::kTryMigrateInstance);
RecordSafepointWithRegisters(
instr->pointer_map(), 1, Safepoint::kNoLazyDeopt);
__ StoreToSafepointRegisterSlot(v0, scratch0());
......
......@@ -14328,14 +14328,19 @@ RUNTIME_FUNCTION(MaybeObject*, Runtime_NotifyContextDisposed) {
}
RUNTIME_FUNCTION(MaybeObject*, Runtime_MigrateInstance) {
RUNTIME_FUNCTION(MaybeObject*, Runtime_TryMigrateInstance) {
HandleScope scope(isolate);
ASSERT(args.length() == 1);
CONVERT_ARG_HANDLE_CHECKED(Object, object, 0);
if (!object->IsJSObject()) return Smi::FromInt(0);
Handle<JSObject> js_object = Handle<JSObject>::cast(object);
if (!js_object->map()->is_deprecated()) return Smi::FromInt(0);
JSObject::MigrateInstance(js_object);
// This call must not cause lazy deopts, because it's called from deferred
// code where we can't handle lazy deopts for lack of a suitable bailout
// ID. So we just try migration and signal failure if necessary,
// which will also trigger a deopt.
Handle<Object> result = JSObject::TryMigrateInstance(js_object);
if (result.is_null()) return Smi::FromInt(0);
return *object;
}
......
......@@ -109,7 +109,7 @@ namespace internal {
F(DebugCallbackSupportsStepping, 1, 1) \
F(DebugPrepareStepInIfStepping, 1, 1) \
F(FlattenString, 1, 1) \
F(MigrateInstance, 1, 1) \
F(TryMigrateInstance, 1, 1) \
F(NotifyContextDisposed, 0, 1) \
F(MaxSmi, 0, 1) \
\
......
......@@ -4995,7 +4995,7 @@ void LCodeGen::DoDeferredInstanceMigration(LCheckMaps* instr, Register object) {
PushSafepointRegistersScope scope(this);
__ push(object);
__ Set(rsi, 0);
__ CallRuntimeSaveDoubles(Runtime::kMigrateInstance);
__ CallRuntimeSaveDoubles(Runtime::kTryMigrateInstance);
RecordSafepointWithRegisters(
instr->pointer_map(), 1, Safepoint::kNoLazyDeopt);
......
// Copyright 2014 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
function f(a, b, c) {
this.a = a;
this.b = b;
this.c = c;
}
var o3 = new f(1, 2, 3.5);
var o4 = new f(1, 2.5, 3);
var o1 = new f(1.5, 2, 3);
var o2 = new f(1.5, 2, 3);
function migrate(o) {
return o.a;
}
// Use migrate to stabilize o1, o2 and o4 in [double, double, smi].
migrate(o4);
migrate(o1);
migrate(o2);
function store_transition(o) {
o.d = 1;
}
// Optimize "store_transition" to transition from [double, double, smi] to
// [double, double, smi, smi]. This adds a dependency on the
// [double, double, smi] map.
store_transition(o4);
store_transition(o1);
store_transition(o2);
%OptimizeFunctionOnNextCall(store_transition);
// Pass in a deprecated object of format [smi, smi, double]. This will migrate
// the instance, forcing a merge with [double, double, smi], ending up with
// [double, double, double], which deprecates [double, double, smi] and
// deoptimizes all dependencies of [double, double, smi], including
// store_transition itself.
store_transition(o3);
Markdown is supported
0% or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment