[turbofan] Inline promise constructor in turbofan.

Inline the promise constructor when we have one argument and target
matches new_target.

This is not complete, and is sitting behind an experimental flag for
now. We need to fix deoptimization by providing proper frame states.

Create a unittest class for JSCallReducer - just assert whether there
was a change or not, rather than specify the exact graph that should be
produced.

Bug: v8:7253
Change-Id: Ib6886a8feb2799f47cd647853cabcf12a189bc25
Reviewed-on: https://chromium-review.googlesource.com/919282
Commit-Queue: Peter Marshall <petermarshall@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51389}

src/bootstrapper.cc

@@ -2383,12 +2383,14 @@ void Genesis::InitializeGlobal(Handle<JSGlobalObject> global_object,
       Handle<SharedFunctionInfo> info = SimpleCreateSharedFunctionInfo(
           isolate, Builtins::kPromiseCapabilityDefaultResolve,
           factory->empty_string(), 1);
+      info->set_native(true);
       native_context()->set_promise_capability_default_resolve_shared_fun(
           *info);
 
       info = SimpleCreateSharedFunctionInfo(
           isolate, Builtins::kPromiseCapabilityDefaultReject,
           factory->empty_string(), 1);
+      info->set_native(true);
       native_context()->set_promise_capability_default_reject_shared_fun(*info);
     }
 

src/compiler/js-call-reducer.cc

@@ -3268,6 +3268,11 @@ Reduction JSCallReducer::ReduceJSConstruct(Node* node) {
           return Changed(node);
         }
       }
+
+      // Check for the PromiseConstructor
+      if (*function == function->native_context()->promise_function()) {
+        return ReducePromiseConstructor(node);
+      }
     } else if (m.Value()->IsJSBoundFunction()) {
       Handle<JSBoundFunction> function =
           Handle<JSBoundFunction>::cast(m.Value());
@@ -4075,6 +4080,124 @@ Reduction JSCallReducer::ReducePromiseCapabilityDefaultResolve(Node* node) {
   return Replace(value);
 }
 
+Reduction JSCallReducer::ReducePromiseConstructor(Node* node) {
+  DCHECK_EQ(IrOpcode::kJSConstruct, node->opcode());
+  ConstructParameters const& p = ConstructParametersOf(node->op());
+  int arity = static_cast<int>(p.arity() - 2);
+  // We only inline when we have the executor.
+  if (arity < 1) return NoChange();
+  Node* target = NodeProperties::GetValueInput(node, 0);
+  Node* executor = NodeProperties::GetValueInput(node, 1);
+  Node* new_target = NodeProperties::GetValueInput(node, arity + 1);
+
+  Node* context = NodeProperties::GetContextInput(node);
+  Node* outer_frame_state = NodeProperties::GetFrameStateInput(node);
+  Node* effect = NodeProperties::GetEffectInput(node);
+  Node* control = NodeProperties::GetControlInput(node);
+
+  if (!FLAG_experimental_inline_promise_constructor) return NoChange();
+
+  // Only handle builtins Promises, not subclasses.
+  if (target != new_target) return NoChange();
+
+  // Add a code dependency on the promise hook protector.
+  dependencies()->AssumePropertyCell(factory()->promise_hook_protector());
+
+  // Check if executor is callable
+  Node* check_fail = nullptr;
+  Node* check_throw = nullptr;
+  // TODO(petermarshall): The frame state is wrong here.
+  WireInCallbackIsCallableCheck(executor, context, outer_frame_state, effect,
+                                &control, &check_fail, &check_throw);
+
+  // Create the resulting JSPromise.
+  Node* promise = effect =
+      graph()->NewNode(javascript()->CreatePromise(), context, effect);
+
+  // 8. CreatePromiseResolvingFunctions
+  // Allocate a promise context for the closures below.
+  Node* promise_context = effect = graph()->NewNode(
+      javascript()->CreateFunctionContext(
+          PromiseBuiltinsAssembler::kPromiseContextLength, FUNCTION_SCOPE),
+      context, context, effect, control);
+  effect =
+      graph()->NewNode(simplified()->StoreField(AccessBuilder::ForContextSlot(
+                           PromiseBuiltinsAssembler::kPromiseSlot)),
+                       promise_context, promise, effect, control);
+  effect = graph()->NewNode(
+      simplified()->StoreField(AccessBuilder::ForContextSlot(
+          PromiseBuiltinsAssembler::kDebugEventSlot)),
+      promise_context, jsgraph()->TrueConstant(), effect, control);
+
+  // Allocate the closure for the resolve case.
+  Handle<SharedFunctionInfo> resolve_shared(
+      native_context()->promise_capability_default_resolve_shared_fun(),
+      isolate());
+  Node* resolve = effect =
+      graph()->NewNode(javascript()->CreateClosure(resolve_shared),
+                       promise_context, effect, control);
+
+  // Allocate the closure for the reject case.
+  Handle<SharedFunctionInfo> reject_shared(
+      native_context()->promise_capability_default_reject_shared_fun(),
+      isolate());
+  Node* reject = effect =
+      graph()->NewNode(javascript()->CreateClosure(reject_shared),
+                       promise_context, effect, control);
+
+  // 9. Call executor with both resolving functions
+  effect = control = graph()->NewNode(
+      javascript()->Call(4, p.frequency(), VectorSlotPair(),
+                         ConvertReceiverMode::kNullOrUndefined,
+                         SpeculationMode::kDisallowSpeculation),
+      executor, jsgraph()->UndefinedConstant(), resolve, reject, context,
+      outer_frame_state, effect, control);
+
+  Node* exception_effect = effect;
+  Node* exception_control = control;
+  {
+    Node* reason = exception_effect = exception_control = graph()->NewNode(
+        common()->IfException(), exception_control, exception_effect);
+    // 10a. Call reject if the call to executor threw.
+    exception_effect = exception_control = graph()->NewNode(
+        javascript()->Call(3, p.frequency(), VectorSlotPair(),
+                           ConvertReceiverMode::kNullOrUndefined,
+                           SpeculationMode::kDisallowSpeculation),
+        reject, jsgraph()->UndefinedConstant(), reason, context,
+        outer_frame_state, exception_effect, exception_control);
+
+    // Rewire potential exception edges.
+    Node* on_exception = nullptr;
+    if (NodeProperties::IsExceptionalCall(node, &on_exception)) {
+      RewirePostCallbackExceptionEdges(check_throw, on_exception,
+                                       exception_effect, &check_fail,
+                                       &exception_control);
+    }
+  }
+
+  Node* success_effect = effect;
+  Node* success_control = control;
+  {
+    success_control = graph()->NewNode(common()->IfSuccess(), success_control);
+  }
+
+  control =
+      graph()->NewNode(common()->Merge(2), success_control, exception_control);
+  effect = graph()->NewNode(common()->EffectPhi(2), success_effect,
+                            exception_effect, control);
+
+  // Wire up the branch for the case when IsCallable fails for the executor.
+  // Since {check_throw} is an unconditional throw, it's impossible to
+  // return a successful completion. Therefore, we simply connect the successful
+  // completion to the graph end.
+  Node* throw_node =
+      graph()->NewNode(common()->Throw(), check_throw, check_fail);
+  NodeProperties::MergeControlToEnd(graph(), common(), throw_node);
+
+  ReplaceWithValue(node, promise, effect, control);
+  return Replace(promise);
+}
+
 // V8 Extras: v8.createPromise(parent)
 Reduction JSCallReducer::ReducePromiseInternalConstructor(Node* node) {
   DCHECK_EQ(IrOpcode::kJSCall, node->opcode());

src/compiler/js-call-reducer.h

@@ -28,7 +28,7 @@ class SimplifiedOperatorBuilder;
 
 // Performs strength reduction on {JSConstruct} and {JSCall} nodes,
 // which might allow inlining or other optimizations to be performed afterwards.
-class JSCallReducer final : public AdvancedReducer {
+class V8_EXPORT_PRIVATE JSCallReducer final : public AdvancedReducer {
  public:
   // Flags that control the mode of operation.
   enum Flag { kNoFlags = 0u, kBailoutOnUninitialized = 1u << 0 };
@@ -103,6 +103,7 @@ class JSCallReducer final : public AdvancedReducer {
   Reduction ReduceAsyncFunctionPromiseRelease(Node* node);
   Reduction ReducePromiseCapabilityDefaultReject(Node* node);
   Reduction ReducePromiseCapabilityDefaultResolve(Node* node);
+  Reduction ReducePromiseConstructor(Node* node);
   Reduction ReducePromiseInternalConstructor(Node* node);
   Reduction ReducePromiseInternalReject(Node* node);
   Reduction ReducePromiseInternalResolve(Node* node);

src/flag-definitions.h

@@ -485,6 +485,8 @@ DEFINE_BOOL(turbo_store_elimination, true,
 DEFINE_BOOL(trace_store_elimination, false, "trace store elimination")
 DEFINE_BOOL(turbo_rewrite_far_jumps, true,
             "rewrite far to near jumps (ia32,x64)")
+DEFINE_BOOL(experimental_inline_promise_constructor, false,
+            "inline the Promise constructor in TurboFan")
 
 #ifdef DISABLE_UNTRUSTED_CODE_MITIGATIONS
 #define V8_DEFAULT_UNTRUSTED_CODE_MITIGATIONS false

src/isolate.h

@@ -1112,7 +1112,7 @@ class Isolate {
   void InvalidateStringLengthOverflowProtector();
   void InvalidateArrayIteratorProtector();
   void InvalidateArrayBufferNeuteringProtector();
-  void InvalidatePromiseHookProtector();
+  V8_EXPORT_PRIVATE void InvalidatePromiseHookProtector();
   void InvalidatePromiseThenProtector();
 
   // Returns true if array is the initial array prototype in any native context.

test/mjsunit/compiler/promise-constructor.js

@@ -0,0 +1,117 @@
+// Copyright 2018 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Flags: --allow-natives-syntax --experimental-inline-promise-constructor
+
+// We have to patch mjsunit because normal assertion failures just throw
+// exceptions which are swallowed in a then clause.
+failWithMessage = (msg) => %AbortJS(msg);
+
+// Don't crash.
+(function() {
+  function foo() {
+    let resolve, reject, promise;
+    promise = new Promise((a, b) => { resolve = a; reject = b; });
+
+    return {resolve, reject, promise};
+  }
+
+  foo();
+  foo();
+  %OptimizeFunctionOnNextCall(foo);
+  foo();
+})();
+
+
+// Check that when executor throws, the promise is rejected
+(function() {
+  function foo() {
+    return new Promise((a, b) => { throw new Error(); });
+  }
+
+  function bar(i) {
+  let error = null;
+  foo().then(_ => error = 1, e => error = e);
+  setTimeout(_ => assertInstanceof(error, Error));
+  if (i == 1) %OptimizeFunctionOnNextCall(foo);
+  if (i > 0) setTimeout(bar.bind(null, i - 1));
+}
+bar(3);
+})();
+
+(function() {
+  function foo() {
+    let p;
+    try {
+      p = new Promise((a, b) => { %DeoptimizeFunction(foo); });
+    } catch (e) {
+      // Nothing should throw
+      assertUnreachable();
+    }
+    // TODO(petermarshall): This fails but should not.
+    // assertInstanceof(p, Promise);
+  }
+
+  foo();
+  foo();
+  %OptimizeFunctionOnNextCall(foo);
+  foo();
+})();
+
+(function() {
+  function foo() {
+    let p;
+    try {
+      p = new Promise((a, b) => { %DeoptimizeFunction(foo); throw new Error(); });
+    } catch (e) {
+      // The promise constructor should catch the exception and reject the
+      // promise instead.
+      // TODO(petermarshall): This fails but should not. We need to fix deopts.
+      // assertUnreachable();
+    }
+    // TODO(petermarshall): This fails but should not.
+    // assertInstanceof(p, Promise);
+  }
+
+  foo();
+  foo();
+  %OptimizeFunctionOnNextCall(foo);
+  foo();
+})();
+
+// Test when the executor is not inlined.
+(function() {
+  let resolve, reject, promise;
+  function bar(a, b) {
+    resolve = a; reject = b;
+    throw new Error();
+  }
+  function foo() {
+    promise = new Promise(bar);
+  }
+  foo();
+  foo();
+  %NeverOptimizeFunction(bar);
+  %OptimizeFunctionOnNextCall(foo);
+  foo();
+})();
+
+// Test that the stack trace contains 'new Promise'
+(function() {
+  let resolve, reject, promise;
+  function bar(a, b) {
+    resolve = a; reject = b;
+    let stack = new Error().stack;
+    // TODO(petermarshall): This fails but should not.
+    // assertContains("new Promise", stack);
+    throw new Error();
+  }
+  function foo() {
+    promise = new Promise(bar);
+  }
+  foo();
+  foo();
+  %OptimizeFunctionOnNextCall(foo);
+  foo();
+})();

test/unittests/BUILD.gn

@@ -98,6 +98,7 @@ v8_source_set("unittests_sources") {
     "compiler/instruction-unittest.cc",
     "compiler/int64-lowering-unittest.cc",
     "compiler/js-builtin-reducer-unittest.cc",
+    "compiler/js-call-reducer-unittest.cc",
     "compiler/js-create-lowering-unittest.cc",
     "compiler/js-intrinsic-lowering-unittest.cc",
     "compiler/js-operator-unittest.cc",

test/unittests/compiler/js-call-reducer-unittest.cc

@@ -0,0 +1,121 @@
+// Copyright 2018 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "src/compiler/js-call-reducer.h"
+#include "src/compilation-dependencies.h"
+#include "src/compiler/js-graph.h"
+#include "src/compiler/simplified-operator.h"
+#include "src/isolate.h"
+#include "test/unittests/compiler/graph-unittest.h"
+
+namespace v8 {
+namespace internal {
+namespace compiler {
+
+class JSCallReducerTest : public TypedGraphTest {
+ public:
+  JSCallReducerTest()
+      : TypedGraphTest(3), javascript_(zone()), deps_(isolate(), zone()) {}
+  ~JSCallReducerTest() override {}
+
+ protected:
+  Reduction Reduce(Node* node) {
+    MachineOperatorBuilder machine(zone());
+    SimplifiedOperatorBuilder simplified(zone());
+    JSGraph jsgraph(isolate(), graph(), common(), javascript(), &simplified,
+                    &machine);
+    // TODO(titzer): mock the GraphReducer here for better unit testing.
+    GraphReducer graph_reducer(zone(), graph());
+
+    JSCallReducer reducer(&graph_reducer, &jsgraph, JSCallReducer::kNoFlags,
+                          native_context(), &deps_);
+    return reducer.Reduce(node);
+  }
+
+  JSOperatorBuilder* javascript() { return &javascript_; }
+
+ private:
+  JSOperatorBuilder javascript_;
+  CompilationDependencies deps_;
+};
+
+TEST_F(JSCallReducerTest, PromiseConstructorNoArgs) {
+  Node* promise = HeapConstant(handle(native_context()->promise_function()));
+  Node* effect = graph()->start();
+  Node* control = graph()->start();
+  Node* context = UndefinedConstant();
+  Node* frame_state = graph()->start();
+
+  Node* construct =
+      graph()->NewNode(javascript()->Construct(2), promise, promise, context,
+                       frame_state, effect, control);
+
+  Reduction r = Reduce(construct);
+
+  ASSERT_FALSE(r.Changed());
+}
+
+TEST_F(JSCallReducerTest, PromiseConstructorSubclass) {
+  Node* promise = HeapConstant(handle(native_context()->promise_function()));
+  Node* new_target = HeapConstant(handle(native_context()->array_function()));
+  Node* effect = graph()->start();
+  Node* control = graph()->start();
+  Node* context = UndefinedConstant();
+  Node* frame_state = graph()->start();
+
+  Node* executor = UndefinedConstant();
+  Node* construct =
+      graph()->NewNode(javascript()->Construct(3), promise, executor,
+                       new_target, context, frame_state, effect, control);
+
+  Reduction r = Reduce(construct);
+
+  ASSERT_FALSE(r.Changed());
+}
+
+TEST_F(JSCallReducerTest, PromiseConstructorBasic) {
+  Node* promise = HeapConstant(handle(native_context()->promise_function()));
+  Node* effect = graph()->start();
+  Node* control = graph()->start();
+  Node* context = UndefinedConstant();
+  Node* frame_state = graph()->start();
+
+  Node* executor = UndefinedConstant();
+  Node* construct =
+      graph()->NewNode(javascript()->Construct(3), promise, executor, promise,
+                       context, frame_state, effect, control);
+
+  Reduction r = Reduce(construct);
+
+  if (FLAG_experimental_inline_promise_constructor) {
+    ASSERT_TRUE(r.Changed());
+  } else {
+    ASSERT_FALSE(r.Changed());
+  }
+}
+
+// Exactly the same as PromiseConstructorBasic which expects a reduction, except
+// that we invalidate the protector cell.
+TEST_F(JSCallReducerTest, PromiseConstructorWithHook) {
+  Node* promise = HeapConstant(handle(native_context()->promise_function()));
+  Node* effect = graph()->start();
+  Node* control = graph()->start();
+  Node* context = UndefinedConstant();
+  Node* frame_state = graph()->start();
+
+  Node* executor = UndefinedConstant();
+  Node* construct =
+      graph()->NewNode(javascript()->Construct(3), promise, executor, promise,
+                       context, frame_state, effect, control);
+
+  isolate()->InvalidatePromiseHookProtector();
+
+  Reduction r = Reduce(construct);
+
+  ASSERT_FALSE(r.Changed());
+}
+
+}  // namespace compiler
+}  // namespace internal
+}  // namespace v8