Revert "Reland "Use off-heap data for type feedback in PolymorphicInstanceCallInstr""

runtime/vm/intermediate_language.cc

Index: runtime/vm/intermediate_language.cc
diff --git a/runtime/vm/intermediate_language.cc b/runtime/vm/intermediate_language.cc
index a7f0dd845b8f0218812d49ab5520138f342cfdb2..beb86543b041187151719ddecf36d59f18185386 100644
--- a/runtime/vm/intermediate_language.cc
+++ b/runtime/vm/intermediate_language.cc
@@ -2741,104 +2741,6 @@ bool UnboxInstr::CanConvertSmi() const {
 }
 
 
-static int OrderById(const CidRangeTarget* a, const CidRangeTarget* b) {
-  // Negative if 'a' should sort before 'b'.
-  ASSERT(a->cid_start == a->cid_end);
-  ASSERT(b->cid_start == b->cid_end);
-  return a->cid_start - b->cid_start;
-}
-
-
-static int OrderByFrequency(const CidRangeTarget* a, const CidRangeTarget* b) {
-  // Negative if 'a' should sort before 'b'.
-  return b->count - a->count;
-}
-
-
-CallTargets* CallTargets::Create(Zone* zone, const ICData& ic_data) {
-  CallTargets* targets = new (zone) CallTargets();
-  if (ic_data.NumberOfChecks() == 0) return targets;
-
-  Function& dummy = Function::Handle(zone);
-
-  bool check_one_arg = ic_data.NumArgsTested() == 1;
-
-  int checks = ic_data.NumberOfChecks();
-  for (int i = 0; i < checks; i++) {
-    intptr_t id = 0;
-    if (check_one_arg) {
-      ic_data.GetOneClassCheckAt(i, &id, &dummy);
-    } else {
-      // The API works for multi dispatch ICs that check more than one
-      // argument, but we know we will only check one arg here, so only the 0th
-      // element of id will be used.
-      GrowableArray<intptr_t> arg_ids;
-      ic_data.GetCheckAt(i, &arg_ids, &dummy);
-      id = arg_ids[0];
-    }
-    Function& function = Function::ZoneHandle(zone, ic_data.GetTargetAt(i));
-    targets->Add(CidRangeTarget(id, id, &function, ic_data.GetCountAt(i)));
-  }
-
-  targets->Sort(OrderById);
-
-  Array& args_desc_array = Array::Handle(zone, ic_data.arguments_descriptor());
-  ArgumentsDescriptor args_desc(args_desc_array);
-  String& name = String::Handle(zone, ic_data.target_name());
-
-  Function& fn = Function::Handle(zone);
-
-  intptr_t length = targets->length();
-
-  // Spread class-ids to preceding classes where a lookup yields the same
-  // method.
-  for (int idx = 0; idx < length; idx++) {
-    int lower_limit_cid = (idx == 0) ? -1 : targets->At(idx - 1).cid_end;
-    const Function& target = *targets->At(idx).target;
-    for (int i = targets->At(idx).cid_start - 1; i > lower_limit_cid; i--) {
-      if (FlowGraphCompiler::LookupMethodFor(i, name, args_desc, &fn) &&
-          fn.raw() == target.raw()) {
-        CidRangeTarget t = targets->At(idx);
-        t.cid_start = i;
-        (*targets)[idx] = t;
-      } else {
-        break;
-      }
-    }
-  }
-  // Spread class-ids to following classes where a lookup yields the same
-  // method.
-  for (int idx = 0; idx < length; idx++) {
-    int upper_limit_cid =
-        (idx == length - 1) ? 1000000000 : targets->At(idx + 1).cid_start;
-    const Function& target = *targets->At(idx).target;
-    for (int i = targets->At(idx).cid_end + 1; i < upper_limit_cid; i++) {
-      if (FlowGraphCompiler::LookupMethodFor(i, name, args_desc, &fn) &&
-          fn.raw() == target.raw()) {
-        (*targets)[idx].cid_end = i;
-      } else {
-        break;
-      }
-    }
-  }
-  // Merge adjacent class id ranges.
-  int dest = 0;
-  for (int src = 1; src < length; src++) {
-    if (targets->At(dest).cid_end + 1 == targets->At(src).cid_start &&
-        targets->At(dest).target->raw() == targets->At(src).target->raw()) {
-      (*targets)[dest].cid_end = targets->At(src).cid_end;
-      (*targets)[dest].count += targets->At(src).count;
-    } else {
-      dest++;
-      if (src != dest) (*targets)[dest] = targets->At(src);
-    }
-  }
-  targets->SetLength(dest + 1);
-  targets->Sort(OrderByFrequency);
-  return targets;
-}
-
-
 // Shared code generation methods (EmitNativeCode and
 // MakeLocationSummary). Only assembly code that can be shared across all
 // architectures can be used. Machine specific register allocation and code
@@ -3267,77 +3169,12 @@ bool InstanceCallInstr::MatchesCoreName(const String& name) {
 }
 
 
-bool CallTargets::HasSingleRecognizedTarget() const {
-  if (!HasSingleTarget()) return false;
-  return MethodRecognizer::RecognizeKind(FirstTarget()) !=
-         MethodRecognizer::kUnknown;
-}
-
-
-bool CallTargets::HasSingleTarget() const {
-  ASSERT(length() != 0);
-  for (int i = 0; i < length(); i++) {
-    if (cid_ranges_[i].target->raw() != cid_ranges_[0].target->raw())
-      return false;
-  }
-  return true;
-}
-
-
-bool CallTargets::IsMonomorphic() const {
-  if (length() != 1) return false;
-  return cid_ranges_[0].cid_start == cid_ranges_[0].cid_end;
-}
-
-
-intptr_t CallTargets::MonomorphicReceiverCid() const {
-  ASSERT(IsMonomorphic());
-  return cid_ranges_[0].cid_start;
-}
-
-
-Function& CallTargets::FirstTarget() const {
-  ASSERT(length() != 0);
-  ASSERT(cid_ranges_[0].target->IsZoneHandle());
-  return *cid_ranges_[0].target;
-}
-
-
-Function& CallTargets::MostPopularTarget() const {
-  ASSERT(length() != 0);
-  ASSERT(cid_ranges_[0].target->IsZoneHandle());
-  for (int i = 1; i < length(); i++) {
-    ASSERT(cid_ranges_[i].count <= cid_ranges_[0].count);
-  }
-  return *cid_ranges_[0].target;
-}
-
+bool PolymorphicInstanceCallInstr::HasSingleRecognizedTarget() const {
+  if (FLAG_precompiled_mode && with_checks()) return false;
 
-intptr_t CallTargets::AggregateCallCount() const {
-  intptr_t sum = 0;
-  for (int i = 0; i < length(); i++) {
-    sum += cid_ranges_[i].count;
-  }
-  return sum;
-}
-
-
-bool PolymorphicInstanceCallInstr::HasOnlyDispatcherOrImplicitAccessorTargets()
-    const {
-  const intptr_t len = targets_.length();
-  Function& target = Function::Handle();
-  for (intptr_t i = 0; i < len; i++) {
-    target ^= targets_[i].target->raw();
-    if (!target.IsDispatcherOrImplicitAccessor()) {
-      return false;
-    }
-  }
-  return true;
-}
-
-
-intptr_t PolymorphicInstanceCallInstr::CallCount() const {
-  return targets().AggregateCallCount();
+  return ic_data().HasOneTarget() &&
+         (MethodRecognizer::RecognizeKind(Function::Handle(
+              ic_data().GetTargetAt(0))) != MethodRecognizer::kUnknown);
 }
 
 
@@ -3345,9 +3182,10 @@ intptr_t PolymorphicInstanceCallInstr::CallCount() const {
 // PolymorphicInstanceCallInstr.
 #if !defined(TARGET_ARCH_DBC)
 void PolymorphicInstanceCallInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
+  ASSERT(ic_data().NumArgsTested() == 1);
   if (!with_checks()) {
-    ASSERT(targets().HasSingleTarget());
-    const Function& target = targets().FirstTarget();
+    ASSERT(ic_data().HasOneTarget());
+    const Function& target = Function::ZoneHandle(ic_data().GetTargetAt(0));
     compiler->GenerateStaticCall(deopt_id(), instance_call()->token_pos(),
                                  target, instance_call()->ArgumentCount(),
                                  instance_call()->argument_names(), locs(),
@@ -3356,7 +3194,7 @@ void PolymorphicInstanceCallInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   }
 
   compiler->EmitPolymorphicInstanceCall(
-      targets_, *instance_call(), instance_call()->ArgumentCount(),
+      ic_data(), instance_call()->ArgumentCount(),
       instance_call()->argument_names(), deopt_id(),
       instance_call()->token_pos(), locs(), complete(), total_call_count());
 }
@@ -3364,29 +3202,22 @@ void PolymorphicInstanceCallInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
 
 
 RawType* PolymorphicInstanceCallInstr::ComputeRuntimeType(
-    const CallTargets& targets) {
+    const ICData& ic_data) {
   bool is_string = true;
   bool is_integer = true;
   bool is_double = true;
 
-  const intptr_t num_checks = targets.length();
+  const intptr_t num_checks = ic_data.NumberOfChecks();
   for (intptr_t i = 0; i < num_checks; i++) {
-    ASSERT(targets[i].target->raw() == targets[0].target->raw());
-    const intptr_t start = targets[i].cid_start;
-    const intptr_t end = targets[i].cid_end;
-    for (intptr_t cid = start; cid <= end; cid++) {
-      is_string = is_string && RawObject::IsStringClassId(cid);
-      is_integer = is_integer && RawObject::IsIntegerClassId(cid);
-      is_double = is_double && (cid == kDoubleCid);
-    }
+    const intptr_t cid = ic_data.GetReceiverClassIdAt(i);
+    is_string = is_string && RawObject::IsStringClassId(cid);
+    is_integer = is_integer && RawObject::IsIntegerClassId(cid);
+    is_double = is_double && (cid == kDoubleCid);
   }
 
   if (is_string) {
-    ASSERT(!is_integer);
-    ASSERT(!is_double);
     return Type::StringType();
   } else if (is_integer) {
-    ASSERT(!is_double);
     return Type::IntType();
   } else if (is_double) {
     return Type::Double();
@@ -3399,18 +3230,12 @@ RawType* PolymorphicInstanceCallInstr::ComputeRuntimeType(
 Definition* InstanceCallInstr::Canonicalize(FlowGraph* flow_graph) {
   const intptr_t receiver_cid = PushArgumentAt(0)->value()->Type()->ToCid();
 
-  // TODO(erikcorry): Even for cold call sites we could still try to look up
-  // methods when we know the receiver cid. We don't currently do this because
-  // it turns the InstanceCall into a PolymorphicInstanceCall which doesn't get
-  // recognized or inlined when it is cold.
-  if (ic_data()->NumberOfUsedChecks() == 0) return this;
-
-  const CallTargets* new_target =
-      FlowGraphCompiler::ResolveCallTargetsForReceiverCid(
-          receiver_cid,
-          String::Handle(flow_graph->zone(), ic_data()->target_name()),
-          Array::Handle(flow_graph->zone(), ic_data()->arguments_descriptor()));
-  if (new_target == NULL) {
+  if (!HasICData()) return this;
+
+  const ICData& new_ic_data =
+      FlowGraphCompiler::TrySpecializeICDataByReceiverCid(*ic_data(),
+                                                          receiver_cid);
+  if (new_ic_data.raw() == ic_data()->raw()) {
     // No specialization.
     return this;
   }
@@ -3418,21 +3243,21 @@ Definition* InstanceCallInstr::Canonicalize(FlowGraph* flow_graph) {
   const bool with_checks = false;
   const bool complete = false;
   PolymorphicInstanceCallInstr* specialized = new PolymorphicInstanceCallInstr(
-      this, *new_target, with_checks, complete);
+      this, new_ic_data, with_checks, complete);
   flow_graph->InsertBefore(this, specialized, env(), FlowGraph::kValue);
   return specialized;
 }
 
 
 Definition* PolymorphicInstanceCallInstr::Canonicalize(FlowGraph* flow_graph) {
-  if (!targets().HasSingleRecognizedTarget()) {
+  if (!HasSingleRecognizedTarget() || with_checks()) {
     return this;
   }
 
-  const Function& target = targets().FirstTarget();
+  const Function& target = Function::Handle(ic_data().GetTargetAt(0));
   if (target.recognized_kind() == MethodRecognizer::kObjectRuntimeType) {
     const AbstractType& type =
-        AbstractType::Handle(ComputeRuntimeType(targets_));
+        AbstractType::Handle(ComputeRuntimeType(ic_data()));
     if (!type.IsNull()) {
       return flow_graph->GetConstant(type);
     }