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"
@@ skipping 35 matching lines @@
   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());
@@ skipping 115 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());
 }
+}