Revert "ART: Do not eagerly type LoopPhi [null, ...]"
Breaks some libcore tests. Revert to unblock others while investigating.
This reverts commit 3a738bfe9784b9ea0f2fccbe75f0c72ede536641.
Change-Id: I9f103c692199b8f9b6e7af469fc424512b57544a
diff --git a/compiler/optimizing/reference_type_propagation.cc b/compiler/optimizing/reference_type_propagation.cc
index bcdbeec..0d05c49 100644
--- a/compiler/optimizing/reference_type_propagation.cc
+++ b/compiler/optimizing/reference_type_propagation.cc
@@ -127,87 +127,6 @@
}
}
-static void CheckHasNoTypedInputs(HInstruction* root_instr) {
- ArenaAllocatorAdapter<void> adapter =
- root_instr->GetBlock()->GetGraph()->GetArena()->Adapter(kArenaAllocReferenceTypePropagation);
-
- ArenaVector<HPhi*> visited_phis(adapter);
- ArenaVector<HInstruction*> worklist(adapter);
- worklist.push_back(root_instr);
-
- while (!worklist.empty()) {
- HInstruction* instr = worklist.back();
- worklist.pop_back();
-
- if (instr->IsPhi() || instr->IsBoundType() || instr->IsNullCheck()) {
- // Expect that both `root_instr` and its inputs have invalid RTI.
- ScopedObjectAccess soa(Thread::Current());
- DCHECK(!instr->GetReferenceTypeInfo().IsValid()) << "Instruction should not have valid RTI.";
-
- // Insert all unvisited inputs to the worklist.
- for (HInputIterator it(instr); !it.Done(); it.Advance()) {
- HInstruction* input = it.Current();
- if (input->IsPhi()) {
- if (ContainsElement(visited_phis, input->AsPhi())) {
- continue;
- } else {
- visited_phis.push_back(input->AsPhi());
- }
- }
- worklist.push_back(input);
- }
- } else if (instr->IsNullConstant()) {
- // The only input of `root_instr` allowed to have valid RTI because it is ignored.
- } else {
- LOG(FATAL) << "Unexpected input " << instr->DebugName() << instr->GetId() << " with RTI "
- << instr->GetReferenceTypeInfo();
- UNREACHABLE();
- }
- }
-}
-
-template<typename Functor>
-static void ForEachUntypedInstruction(HGraph* graph, Functor fn) {
- ScopedObjectAccess soa(Thread::Current());
- for (HReversePostOrderIterator block_it(*graph); !block_it.Done(); block_it.Advance()) {
- for (HInstructionIterator it(block_it.Current()->GetPhis()); !it.Done(); it.Advance()) {
- HInstruction* instr = it.Current();
- if (instr->GetType() == Primitive::kPrimNot && !instr->GetReferenceTypeInfo().IsValid()) {
- fn(instr);
- }
- }
- for (HInstructionIterator it(block_it.Current()->GetInstructions()); !it.Done(); it.Advance()) {
- HInstruction* instr = it.Current();
- if (instr->GetType() == Primitive::kPrimNot && !instr->GetReferenceTypeInfo().IsValid()) {
- fn(instr);
- }
- }
- }
-}
-
-void ReferenceTypePropagation::SetUntypedInstructionsToObject() {
- // In some cases, the fix-point iteration will leave kPrimNot instructions with
- // invalid RTI because bytecode does not provide enough typing information.
- // Set the RTI of such instructions to Object.
- // Example:
- // MyClass a = null, b = null;
- // while (a == null) {
- // if (cond) { a = b; } else { b = a; }
- // }
-
- if (kIsDebugBuild) {
- // Test that if we are going to set RTI from invalid to Object, that
- // instruction did not have any typed instructions in its def-use chain
- // and therefore its type could not be inferred.
- ForEachUntypedInstruction(graph_, [](HInstruction* instr) { CheckHasNoTypedInputs(instr); });
- }
-
- ReferenceTypeInfo obj_rti = ReferenceTypeInfo::Create(object_class_handle_, /* is_exact */ false);
- ForEachUntypedInstruction(graph_, [obj_rti](HInstruction* instr) {
- instr->SetReferenceTypeInfo(obj_rti);
- });
-}
-
void ReferenceTypePropagation::Run() {
// To properly propagate type info we need to visit in the dominator-based order.
// Reverse post order guarantees a node's dominators are visited first.
@@ -217,7 +136,6 @@
}
ProcessWorklist();
- SetUntypedInstructionsToObject();
ValidateTypes();
}
@@ -616,9 +534,8 @@
void RTPVisitor::VisitNullCheck(HNullCheck* instr) {
ScopedObjectAccess soa(Thread::Current());
ReferenceTypeInfo parent_rti = instr->InputAt(0)->GetReferenceTypeInfo();
- if (parent_rti.IsValid()) {
- instr->SetReferenceTypeInfo(parent_rti);
- }
+ DCHECK(parent_rti.IsValid());
+ instr->SetReferenceTypeInfo(parent_rti);
}
void RTPVisitor::VisitFakeString(HFakeString* instr) {
@@ -671,16 +588,11 @@
}
if (phi->GetBlock()->IsLoopHeader()) {
- ScopedObjectAccess soa(Thread::Current());
// Set the initial type for the phi. Use the non back edge input for reaching
// a fixed point faster.
- HInstruction* first_input = phi->InputAt(0);
- ReferenceTypeInfo first_input_rti = first_input->GetReferenceTypeInfo();
- if (first_input_rti.IsValid() && !first_input->IsNullConstant()) {
- phi->SetCanBeNull(first_input->CanBeNull());
- phi->SetReferenceTypeInfo(first_input_rti);
- }
AddToWorklist(phi);
+ phi->SetCanBeNull(phi->InputAt(0)->CanBeNull());
+ phi->SetReferenceTypeInfo(phi->InputAt(0)->GetReferenceTypeInfo());
} else {
// Eagerly compute the type of the phi, for quicker convergence. Note
// that we don't need to add users to the worklist because we are
@@ -771,7 +683,7 @@
instr->SetReferenceTypeInfo(parent_rti);
}
} else if (instr->IsArrayGet()) {
- // TODO: consider if it's worth "looking back" and binding the input object
+ // TODO: consider if it's worth "looking back" and bounding the input object
// to an array type.
UpdateArrayGet(instr->AsArrayGet(), handles_, object_class_handle_);
} else {
@@ -858,10 +770,7 @@
}
}
}
-
- if (new_rti.IsValid()) {
- instr->SetReferenceTypeInfo(new_rti);
- }
+ instr->SetReferenceTypeInfo(new_rti);
}
// Re-computes and updates the nullability of the instruction. Returns whether or
diff --git a/compiler/optimizing/reference_type_propagation.h b/compiler/optimizing/reference_type_propagation.h
index 21789e1..5c05592 100644
--- a/compiler/optimizing/reference_type_propagation.h
+++ b/compiler/optimizing/reference_type_propagation.h
@@ -57,7 +57,6 @@
SHARED_REQUIRES(Locks::mutator_lock_);
void ValidateTypes();
- void SetUntypedInstructionsToObject();
StackHandleScopeCollection* handles_;
diff --git a/test/450-checker-types/src/Main.java b/test/450-checker-types/src/Main.java
index cea1d5a..ec63057 100644
--- a/test/450-checker-types/src/Main.java
+++ b/test/450-checker-types/src/Main.java
@@ -618,35 +618,6 @@
getSuper();
}
- /// CHECK-START: void Main.testLoopPhiWithNullFirstInput(boolean) reference_type_propagation (after)
- /// CHECK-DAG: <<Null:l\d+>> NullConstant
- /// CHECK-DAG: <<Main:l\d+>> NewInstance klass:Main exact:true
- /// CHECK-DAG: <<LoopPhi:l\d+>> Phi [<<Null>>,<<LoopPhi>>,<<Main>>] klass:Main exact:true
- private void testLoopPhiWithNullFirstInput(boolean cond) {
- Main a = null;
- while (a == null) {
- if (cond) {
- a = new Main();
- }
- }
- }
-
- /// CHECK-START: void Main.testLoopPhisWithNullAndCrossUses(boolean) reference_type_propagation (after)
- /// CHECK-DAG: <<Null:l\d+>> NullConstant
- /// CHECK-DAG: <<PhiA:l\d+>> Phi [<<Null>>,<<PhiB:l\d+>>,<<PhiA>>] klass:java.lang.Object exact:false
- /// CHECK-DAG: <<PhiB>> Phi [<<Null>>,<<PhiB>>,<<PhiA>>] klass:java.lang.Object exact:false
- private void testLoopPhisWithNullAndCrossUses(boolean cond) {
- Main a = null;
- Main b = null;
- while (a == null) {
- if (cond) {
- a = b;
- } else {
- b = a;
- }
- }
- }
-
public static void main(String[] args) {
}
}
