ART: Change IndirectReferenceTable

Change cookie structure to allow for more entries. Use a local
hole-count caching scheme. The design is driven by two
considerations. For one, the change is small and mostly local.
The other point is to still allow inlining of functions involved
with JNI transitions.

This change is in preparation for a resizable backing table for
"unlimite" local references.

micro_native tests show changes are in the noise.

Bug: 32125344
Test: m test-art-host
Change-Id: I08ff5d6eaed75d13ec88f469fb0d18328a0eeb70
diff --git a/runtime/indirect_reference_table_test.cc b/runtime/indirect_reference_table_test.cc
index d7026de..1baec28 100644
--- a/runtime/indirect_reference_table_test.cc
+++ b/runtime/indirect_reference_table_test.cc
@@ -65,7 +65,7 @@
   Handle<mirror::Object> obj3 = hs.NewHandle(c->AllocObject(soa.Self()));
   ASSERT_TRUE(obj3.Get() != nullptr);
 
-  const uint32_t cookie = IRT_FIRST_SEGMENT;
+  const IRTSegmentState cookie = kIRTFirstSegment;
 
   CheckDump(&irt, 0, 0);
 
@@ -257,4 +257,208 @@
   CheckDump(&irt, 0, 0);
 }
 
+TEST_F(IndirectReferenceTableTest, Holes) {
+  // Test the explicitly named cases from the IRT implementation:
+  //
+  // 1) Segment with holes (current_num_holes_ > 0), push new segment, add/remove reference
+  // 2) Segment with holes (current_num_holes_ > 0), pop segment, add/remove reference
+  // 3) Segment with holes (current_num_holes_ > 0), push new segment, pop segment, add/remove
+  //    reference
+  // 4) Empty segment, push new segment, create a hole, pop a segment, add/remove a reference
+  // 5) Base segment, push new segment, create a hole, pop a segment, push new segment, add/remove
+  //    reference
+
+  ScopedObjectAccess soa(Thread::Current());
+  static const size_t kTableMax = 10;
+
+  mirror::Class* c = class_linker_->FindSystemClass(soa.Self(), "Ljava/lang/Object;");
+  StackHandleScope<5> hs(soa.Self());
+  ASSERT_TRUE(c != nullptr);
+  Handle<mirror::Object> obj0 = hs.NewHandle(c->AllocObject(soa.Self()));
+  ASSERT_TRUE(obj0.Get() != nullptr);
+  Handle<mirror::Object> obj1 = hs.NewHandle(c->AllocObject(soa.Self()));
+  ASSERT_TRUE(obj1.Get() != nullptr);
+  Handle<mirror::Object> obj2 = hs.NewHandle(c->AllocObject(soa.Self()));
+  ASSERT_TRUE(obj2.Get() != nullptr);
+  Handle<mirror::Object> obj3 = hs.NewHandle(c->AllocObject(soa.Self()));
+  ASSERT_TRUE(obj3.Get() != nullptr);
+  Handle<mirror::Object> obj4 = hs.NewHandle(c->AllocObject(soa.Self()));
+  ASSERT_TRUE(obj4.Get() != nullptr);
+
+  std::string error_msg;
+
+  // 1) Segment with holes (current_num_holes_ > 0), push new segment, add/remove reference.
+  {
+    IndirectReferenceTable irt(kTableMax, kLocal, &error_msg);
+    ASSERT_TRUE(irt.IsValid()) << error_msg;
+
+    const IRTSegmentState cookie0 = kIRTFirstSegment;
+
+    CheckDump(&irt, 0, 0);
+
+    IndirectRef iref0 = irt.Add(cookie0, obj0.Get());
+    IndirectRef iref1 = irt.Add(cookie0, obj1.Get());
+    IndirectRef iref2 = irt.Add(cookie0, obj2.Get());
+
+    EXPECT_TRUE(irt.Remove(cookie0, iref1));
+
+    // New segment.
+    const IRTSegmentState cookie1 = irt.GetSegmentState();
+
+    IndirectRef iref3 = irt.Add(cookie1, obj3.Get());
+
+    // Must not have filled the previous hole.
+    EXPECT_EQ(irt.Capacity(), 4u);
+    EXPECT_TRUE(irt.Get(iref1) == nullptr);
+    CheckDump(&irt, 3, 3);
+
+    UNUSED(iref0, iref1, iref2, iref3);
+  }
+
+  // 2) Segment with holes (current_num_holes_ > 0), pop segment, add/remove reference
+  {
+    IndirectReferenceTable irt(kTableMax, kGlobal, &error_msg);
+    ASSERT_TRUE(irt.IsValid()) << error_msg;
+
+    const IRTSegmentState cookie0 = kIRTFirstSegment;
+
+    CheckDump(&irt, 0, 0);
+
+    IndirectRef iref0 = irt.Add(cookie0, obj0.Get());
+
+    // New segment.
+    const IRTSegmentState cookie1 = irt.GetSegmentState();
+
+    IndirectRef iref1 = irt.Add(cookie1, obj1.Get());
+    IndirectRef iref2 = irt.Add(cookie1, obj2.Get());
+    IndirectRef iref3 = irt.Add(cookie1, obj3.Get());
+
+    EXPECT_TRUE(irt.Remove(cookie1, iref2));
+
+    // Pop segment.
+    irt.SetSegmentState(cookie1);
+
+    IndirectRef iref4 = irt.Add(cookie1, obj4.Get());
+
+    EXPECT_EQ(irt.Capacity(), 2u);
+    EXPECT_TRUE(irt.Get(iref2) == nullptr);
+    CheckDump(&irt, 2, 2);
+
+    UNUSED(iref0, iref1, iref2, iref3, iref4);
+  }
+
+  // 3) Segment with holes (current_num_holes_ > 0), push new segment, pop segment, add/remove
+  //    reference.
+  {
+    IndirectReferenceTable irt(kTableMax, kGlobal, &error_msg);
+    ASSERT_TRUE(irt.IsValid()) << error_msg;
+
+    const IRTSegmentState cookie0 = kIRTFirstSegment;
+
+    CheckDump(&irt, 0, 0);
+
+    IndirectRef iref0 = irt.Add(cookie0, obj0.Get());
+
+    // New segment.
+    const IRTSegmentState cookie1 = irt.GetSegmentState();
+
+    IndirectRef iref1 = irt.Add(cookie1, obj1.Get());
+    IndirectRef iref2 = irt.Add(cookie1, obj2.Get());
+
+    EXPECT_TRUE(irt.Remove(cookie1, iref1));
+
+    // New segment.
+    const IRTSegmentState cookie2 = irt.GetSegmentState();
+
+    IndirectRef iref3 = irt.Add(cookie2, obj3.Get());
+
+    // Pop segment.
+    irt.SetSegmentState(cookie2);
+
+    IndirectRef iref4 = irt.Add(cookie1, obj4.Get());
+
+    EXPECT_EQ(irt.Capacity(), 3u);
+    EXPECT_TRUE(irt.Get(iref1) == nullptr);
+    CheckDump(&irt, 3, 3);
+
+    UNUSED(iref0, iref1, iref2, iref3, iref4);
+  }
+
+  // 4) Empty segment, push new segment, create a hole, pop a segment, add/remove a reference.
+  {
+    IndirectReferenceTable irt(kTableMax, kGlobal, &error_msg);
+    ASSERT_TRUE(irt.IsValid()) << error_msg;
+
+    const IRTSegmentState cookie0 = kIRTFirstSegment;
+
+    CheckDump(&irt, 0, 0);
+
+    IndirectRef iref0 = irt.Add(cookie0, obj0.Get());
+
+    // New segment.
+    const IRTSegmentState cookie1 = irt.GetSegmentState();
+
+    IndirectRef iref1 = irt.Add(cookie1, obj1.Get());
+    EXPECT_TRUE(irt.Remove(cookie1, iref1));
+
+    // Emptied segment, push new one.
+    const IRTSegmentState cookie2 = irt.GetSegmentState();
+
+    IndirectRef iref2 = irt.Add(cookie1, obj1.Get());
+    IndirectRef iref3 = irt.Add(cookie1, obj2.Get());
+    IndirectRef iref4 = irt.Add(cookie1, obj3.Get());
+
+    EXPECT_TRUE(irt.Remove(cookie1, iref3));
+
+    // Pop segment.
+    UNUSED(cookie2);
+    irt.SetSegmentState(cookie1);
+
+    IndirectRef iref5 = irt.Add(cookie1, obj4.Get());
+
+    EXPECT_EQ(irt.Capacity(), 2u);
+    EXPECT_TRUE(irt.Get(iref3) == nullptr);
+    CheckDump(&irt, 2, 2);
+
+    UNUSED(iref0, iref1, iref2, iref3, iref4, iref5);
+  }
+
+  // 5) Base segment, push new segment, create a hole, pop a segment, push new segment, add/remove
+  //    reference
+  {
+    IndirectReferenceTable irt(kTableMax, kGlobal, &error_msg);
+    ASSERT_TRUE(irt.IsValid()) << error_msg;
+
+    const IRTSegmentState cookie0 = kIRTFirstSegment;
+
+    CheckDump(&irt, 0, 0);
+
+    IndirectRef iref0 = irt.Add(cookie0, obj0.Get());
+
+    // New segment.
+    const IRTSegmentState cookie1 = irt.GetSegmentState();
+
+    IndirectRef iref1 = irt.Add(cookie1, obj1.Get());
+    IndirectRef iref2 = irt.Add(cookie1, obj1.Get());
+    IndirectRef iref3 = irt.Add(cookie1, obj2.Get());
+
+    EXPECT_TRUE(irt.Remove(cookie1, iref2));
+
+    // Pop segment.
+    irt.SetSegmentState(cookie1);
+
+    // Push segment.
+    const IRTSegmentState cookie1_second = irt.GetSegmentState();
+    UNUSED(cookie1_second);
+
+    IndirectRef iref4 = irt.Add(cookie1, obj3.Get());
+
+    EXPECT_EQ(irt.Capacity(), 2u);
+    EXPECT_TRUE(irt.Get(iref3) == nullptr);
+    CheckDump(&irt, 2, 2);
+
+    UNUSED(iref0, iref1, iref2, iref3, iref4);
+  }
+}
+
 }  // namespace art