Flesh out vector ic state query and set mechanisms.

test/cctest/test-feedback-vector.cc

 // Copyright 2014 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/v8.h"
 #include "test/cctest/cctest.h"
 
 #include "src/api.h"
 #include "src/debug.h"
 #include "src/execution.h"
 #include "src/factory.h"
 #include "src/global-handles.h"
 #include "src/macro-assembler.h"
 #include "src/objects.h"
 
 using namespace v8::internal;
 
 namespace {
 
 TEST(VectorStructure) {
   LocalContext context;
   v8::HandleScope scope(context->GetIsolate());
   Isolate* isolate = CcTest::i_isolate();
   Factory* factory = isolate->factory();
 
   // Empty vectors are the empty fixed array.
-  Handle<TypeFeedbackVector> vector = factory->NewTypeFeedbackVector(0, 0);
+  FeedbackVectorSpec empty;
+  Handle<TypeFeedbackVector> vector = factory->NewTypeFeedbackVector(empty);
   CHECK(Handle<FixedArray>::cast(vector)
             .is_identical_to(factory->empty_fixed_array()));
   // Which can nonetheless be queried.
   CHECK_EQ(0, vector->ic_with_type_info_count());
   CHECK_EQ(0, vector->ic_generic_count());
   CHECK_EQ(0, vector->Slots());
   CHECK_EQ(0, vector->ICSlots());
 
-  vector = factory->NewTypeFeedbackVector(1, 0);
+  FeedbackVectorSpec one_slot(1, 0);
+  vector = factory->NewTypeFeedbackVector(one_slot);
   CHECK_EQ(1, vector->Slots());
   CHECK_EQ(0, vector->ICSlots());
 
-  vector = factory->NewTypeFeedbackVector(0, 1);
+  FeedbackVectorSpec one_icslot(0, 1);
+  vector = factory->NewTypeFeedbackVector(one_icslot);
   CHECK_EQ(0, vector->Slots());
   CHECK_EQ(1, vector->ICSlots());
 
-  vector = factory->NewTypeFeedbackVector(3, 5);
+  FeedbackVectorSpec spec(3, 5);
+  vector = factory->NewTypeFeedbackVector(spec);
   CHECK_EQ(3, vector->Slots());
   CHECK_EQ(5, vector->ICSlots());
 
   int metadata_length = vector->ic_metadata_length();
   if (!FLAG_vector_ics) {
     CHECK_EQ(0, metadata_length);
   } else {
     CHECK(metadata_length > 0);
   }
 
   int index = vector->GetIndex(FeedbackVectorSlot(0));
+
   CHECK_EQ(TypeFeedbackVector::kReservedIndexCount + metadata_length, index);
   CHECK(FeedbackVectorSlot(0) == vector->ToSlot(index));
 
   index = vector->GetIndex(FeedbackVectorICSlot(0));
   CHECK_EQ(index,
            TypeFeedbackVector::kReservedIndexCount + metadata_length + 3);
   CHECK(FeedbackVectorICSlot(0) == vector->ToICSlot(index));
 
   CHECK_EQ(TypeFeedbackVector::kReservedIndexCount + metadata_length + 3 + 5,
            vector->length());
 }
 
 
 // IC slots need an encoding to recognize what is in there.
 TEST(VectorICMetadata) {
   LocalContext context;
   v8::HandleScope scope(context->GetIsolate());
   if (!FLAG_vector_ics) {
     // If FLAG_vector_ics is false, we only store CALL_ICs in the vector, so
     // there is no need for metadata to describe the slots.
     return;
   }
   Isolate* isolate = CcTest::i_isolate();
   Factory* factory = isolate->factory();
 
-  Handle<TypeFeedbackVector> vector =
-      factory->NewTypeFeedbackVector(10, 3 * 10);
-  CHECK_EQ(10, vector->Slots());
-  CHECK_EQ(3 * 10, vector->ICSlots());
-
+  FeedbackVectorSpec spec(10, 3 * 10);
   // Set metadata.
   for (int i = 0; i < 30; i++) {
     Code::Kind kind;
     if (i % 3 == 0) {
       kind = Code::CALL_IC;
     } else if (i % 3 == 1) {
       kind = Code::LOAD_IC;
     } else {
       kind = Code::KEYED_LOAD_IC;
     }
-    vector->SetKind(FeedbackVectorICSlot(i), kind);
+    spec.SetKind(i, kind);
   }
 
+  Handle<TypeFeedbackVector> vector = factory->NewTypeFeedbackVector(spec);
+  CHECK_EQ(10, vector->Slots());
+  CHECK_EQ(3 * 10, vector->ICSlots());
+
   // Meanwhile set some feedback values and type feedback values to
   // verify the data structure remains intact.
   vector->change_ic_with_type_info_count(100);
   vector->change_ic_generic_count(3333);
   vector->Set(FeedbackVectorSlot(0), *vector);
 
-  // Verify the metadata remains the same.
+  // Verify the metadata is correctly set up from the spec.
   for (int i = 0; i < 30; i++) {
     Code::Kind kind = vector->GetKind(FeedbackVectorICSlot(i));
     if (i % 3 == 0) {
       CHECK_EQ(Code::CALL_IC, kind);
     } else if (i % 3 == 1) {
       CHECK_EQ(Code::LOAD_IC, kind);
     } else {
       CHECK_EQ(Code::KEYED_LOAD_IC, kind);
     }
   }
 }
 
 
 TEST(VectorSlotClearing) {
   LocalContext context;
   v8::HandleScope scope(context->GetIsolate());
   Isolate* isolate = CcTest::i_isolate();
   Factory* factory = isolate->factory();
 
   // We only test clearing FeedbackVectorSlots, not FeedbackVectorICSlots.
   // The reason is that FeedbackVectorICSlots need a full code environment
   // to fully test (See VectorICProfilerStatistics test below).
-  Handle<TypeFeedbackVector> vector = factory->NewTypeFeedbackVector(5, 0);
+  FeedbackVectorSpec spec(5, 0);
+  Handle<TypeFeedbackVector> vector = factory->NewTypeFeedbackVector(spec);
 
   // Fill with information
   vector->Set(FeedbackVectorSlot(0), Smi::FromInt(1));
   vector->Set(FeedbackVectorSlot(1), *factory->fixed_array_map());
   Handle<AllocationSite> site = factory->NewAllocationSite();
   vector->Set(FeedbackVectorSlot(2), *site);
 
   vector->ClearSlots(NULL);
 
   // The feedback vector slots are cleared. AllocationSites are granted
@@ skipping 42 matching lines @@
   CHECK_EQ(0, feedback_vector->ic_with_type_info_count());
   CHECK_EQ(0, feedback_vector->ic_generic_count());
 
   // The Array function is special. A call to array remains monomorphic
   // and isn't cleared by gc because an AllocationSite is being held.
   CompileRun("f(Array);");
   feedback_vector = f->shared()->feedback_vector();
   CHECK_EQ(1, feedback_vector->ic_with_type_info_count());
   CHECK_EQ(0, feedback_vector->ic_generic_count());
 
-  int ic_slot = FLAG_vector_ics ? 1 : 0;
+  int ic_slot = 0;
   CHECK(
       feedback_vector->Get(FeedbackVectorICSlot(ic_slot))->IsAllocationSite());
   heap->CollectAllGarbage(i::Heap::kNoGCFlags);
   feedback_vector = f->shared()->feedback_vector();
   CHECK_EQ(1, feedback_vector->ic_with_type_info_count());
   CHECK_EQ(0, feedback_vector->ic_generic_count());
   CHECK(
       feedback_vector->Get(FeedbackVectorICSlot(ic_slot))->IsAllocationSite());
 }
 
 
 TEST(VectorCallICStates) {
   if (i::FLAG_always_opt) return;
   CcTest::InitializeVM();
   LocalContext context;
   v8::HandleScope scope(context->GetIsolate());
   Isolate* isolate = CcTest::i_isolate();
   Heap* heap = isolate->heap();
 
   // Make sure function f has a call that uses a type feedback slot.
   CompileRun(
       "function foo() { return 17; }"
       "function f(a) { a(); } f(foo);");
   Handle<JSFunction> f = v8::Utils::OpenHandle(
       *v8::Handle<v8::Function>::Cast(CcTest::global()->Get(v8_str("f"))));
   // There should be one IC.
   Handle<TypeFeedbackVector> feedback_vector =
       Handle<TypeFeedbackVector>(f->shared()->feedback_vector(), isolate);
-  FeedbackVectorICSlot slot(FLAG_vector_ics ? 1 : 0);
+  FeedbackVectorICSlot slot(0);
   CallICNexus nexus(feedback_vector, slot);
   CHECK_EQ(MONOMORPHIC, nexus.StateFromFeedback());
   // CallIC doesn't return map feedback.
   CHECK_EQ(NULL, nexus.FindFirstMap());
 
   CompileRun("f(function() { return 16; })");
   CHECK_EQ(GENERIC, nexus.StateFromFeedback());
 
   // After a collection, state should be reset to UNINITIALIZED.
   heap->CollectAllGarbage(i::Heap::kNoGCFlags);
   CHECK_EQ(UNINITIALIZED, nexus.StateFromFeedback());
 
   // Array is special. It will remain monomorphic across gcs and it contains an
   // AllocationSite.
   CompileRun("f(Array)");
   CHECK_EQ(MONOMORPHIC, nexus.StateFromFeedback());
   CHECK(feedback_vector->Get(FeedbackVectorICSlot(slot))->IsAllocationSite());
 
   heap->CollectAllGarbage(i::Heap::kNoGCFlags);
   CHECK_EQ(MONOMORPHIC, nexus.StateFromFeedback());
 }
+
+
+TEST(VectorLoadICStates) {
+  if (i::FLAG_always_opt || !i::FLAG_vector_ics) return;
+  CcTest::InitializeVM();
+  LocalContext context;
+  v8::HandleScope scope(context->GetIsolate());
+  Isolate* isolate = CcTest::i_isolate();
+  Heap* heap = isolate->heap();
+
+  // Make sure function f has a call that uses a type feedback slot.
+  CompileRun(
+      "var o = { foo: 3 };"
+      "function f(a) { return a.foo; } f(o);");
+  Handle<JSFunction> f = v8::Utils::OpenHandle(
+      *v8::Handle<v8::Function>::Cast(CcTest::global()->Get(v8_str("f"))));
+  // There should be one IC.
+  Handle<TypeFeedbackVector> feedback_vector =
+      Handle<TypeFeedbackVector>(f->shared()->feedback_vector(), isolate);
+  FeedbackVectorICSlot slot(0);
+  LoadICNexus nexus(feedback_vector, slot);
+  CHECK_EQ(PREMONOMORPHIC, nexus.StateFromFeedback());
+
+  CompileRun("f(o)");
+  CHECK_EQ(MONOMORPHIC, nexus.StateFromFeedback());
+  // Verify that the monomorphic map is the one we expect.
+  Handle<JSObject> o = v8::Utils::OpenHandle(
+      *v8::Handle<v8::Object>::Cast(CcTest::global()->Get(v8_str("o"))));
+  CHECK_EQ(o->map(), nexus.FindFirstMap());
+
+  // Now go polymorphic.
+  CompileRun("f({ blarg: 3, foo: 2 })");
+  CHECK_EQ(POLYMORPHIC, nexus.StateFromFeedback());
+
+  CompileRun(
+      "delete o.foo;"
+      "f(o)");
+  CHECK_EQ(POLYMORPHIC, nexus.StateFromFeedback());
+
+  CompileRun("f({ blarg: 3, torino: 10, foo: 2 })");
+  CHECK_EQ(POLYMORPHIC, nexus.StateFromFeedback());
+  MapHandleList maps;
+  nexus.FindAllMaps(&maps);
+  CHECK_EQ(4, maps.length());
+
+  // Finally driven megamorphic.
+  CompileRun("f({ blarg: 3, gran: 3, torino: 10, foo: 2 })");
+  CHECK_EQ(MEGAMORPHIC, nexus.StateFromFeedback());
+  CHECK_EQ(NULL, nexus.FindFirstMap());
+
+  // After a collection, state should be reset to PREMONOMORPHIC.
+  heap->CollectAllGarbage(i::Heap::kNoGCFlags);
+  CHECK_EQ(PREMONOMORPHIC, nexus.StateFromFeedback());
 }
+}