Revert "Revert "Revert "Revert "Use the object class as top in reference type propagation""""
This reverts commit b734808d0c93af98ec4e3539fdb0a8c0787263b0.
Change-Id: Ifd925f166761bcb9be2268ff0fc9fa3a72f00c6f
diff --git a/compiler/optimizing/graph_visualizer.cc b/compiler/optimizing/graph_visualizer.cc
index 46d821e..3e6a263 100644
--- a/compiler/optimizing/graph_visualizer.cc
+++ b/compiler/optimizing/graph_visualizer.cc
@@ -464,28 +464,19 @@
} else {
StartAttributeStream("loop") << "B" << info->GetHeader()->GetBlockId();
}
- } else if (IsReferenceTypePropagationPass() && is_after_pass_) {
- if (instruction->GetType() == Primitive::kPrimNot) {
- if (instruction->IsLoadClass()) {
- ReferenceTypeInfo info = instruction->AsLoadClass()->GetLoadedClassRTI();
- ScopedObjectAccess soa(Thread::Current());
- if (info.GetTypeHandle().GetReference() != nullptr) {
- StartAttributeStream("klass") << PrettyDescriptor(info.GetTypeHandle().Get());
- } else {
- StartAttributeStream("klass") << "unresolved";
- }
- } else {
- ReferenceTypeInfo info = instruction->GetReferenceTypeInfo();
- if (info.IsTop()) {
- StartAttributeStream("klass") << "java.lang.Object";
- } else {
- ScopedObjectAccess soa(Thread::Current());
- StartAttributeStream("klass") << PrettyDescriptor(info.GetTypeHandle().Get());
- }
- StartAttributeStream("can_be_null")
- << std::boolalpha << instruction->CanBeNull() << std::noboolalpha;
- StartAttributeStream("exact") << std::boolalpha << info.IsExact() << std::noboolalpha;
- }
+ } else if (IsReferenceTypePropagationPass()
+ && (instruction->GetType() == Primitive::kPrimNot)) {
+ ReferenceTypeInfo info = instruction->IsLoadClass()
+ ? instruction->AsLoadClass()->GetLoadedClassRTI()
+ : instruction->GetReferenceTypeInfo();
+ ScopedObjectAccess soa(Thread::Current());
+ if (info.IsValid()) {
+ StartAttributeStream("klass") << PrettyDescriptor(info.GetTypeHandle().Get());
+ StartAttributeStream("can_be_null")
+ << std::boolalpha << instruction->CanBeNull() << std::noboolalpha;
+ StartAttributeStream("exact") << std::boolalpha << info.IsExact() << std::noboolalpha;
+ } else {
+ DCHECK(!is_after_pass_) << "Type info should be valid after reference type propagation";
}
}
if (disasm_info_ != nullptr) {
diff --git a/compiler/optimizing/inliner.cc b/compiler/optimizing/inliner.cc
index c185b58..d6b8aa4 100644
--- a/compiler/optimizing/inliner.cc
+++ b/compiler/optimizing/inliner.cc
@@ -109,10 +109,8 @@
receiver = receiver->InputAt(0);
}
ReferenceTypeInfo info = receiver->GetReferenceTypeInfo();
- if (info.IsTop()) {
- // We have no information on the receiver.
- return nullptr;
- } else if (!info.IsExact()) {
+ DCHECK(info.IsValid()) << "Invalid RTI for " << receiver->DebugName();
+ if (!info.IsExact()) {
// We currently only support inlining with known receivers.
// TODO: Remove this check, we should be able to inline final methods
// on unknown receivers.
@@ -273,11 +271,11 @@
const DexFile::CodeItem* code_item = resolved_method->GetCodeItem();
const DexFile& callee_dex_file = *resolved_method->GetDexFile();
uint32_t method_index = resolved_method->GetDexMethodIndex();
-
+ ClassLinker* class_linker = caller_compilation_unit_.GetClassLinker();
DexCompilationUnit dex_compilation_unit(
nullptr,
caller_compilation_unit_.GetClassLoader(),
- caller_compilation_unit_.GetClassLinker(),
+ class_linker,
*resolved_method->GetDexFile(),
code_item,
resolved_method->GetDeclaringClass()->GetDexClassDefIndex(),
@@ -450,7 +448,33 @@
}
}
- callee_graph->InlineInto(graph_, invoke_instruction);
+ HInstruction* return_replacement = callee_graph->InlineInto(graph_, invoke_instruction);
+
+ // When merging the graph we might create a new NullConstant in the caller graph which does
+ // not have the chance to be typed. We assign the correct type here so that we can keep the
+ // assertion that every reference has a valid type. This also simplifies checks along the way.
+ HNullConstant* null_constant = graph_->GetNullConstant();
+ if (!null_constant->GetReferenceTypeInfo().IsValid()) {
+ ReferenceTypeInfo::TypeHandle obj_handle =
+ handles_->NewHandle(class_linker->GetClassRoot(ClassLinker::kJavaLangObject));
+ null_constant->SetReferenceTypeInfo(
+ ReferenceTypeInfo::Create(obj_handle, false /* is_exact */));
+ }
+
+ if ((return_replacement != nullptr)
+ && (return_replacement->GetType() == Primitive::kPrimNot)) {
+ if (!return_replacement->GetReferenceTypeInfo().IsValid()) {
+ // Make sure that we have a valid type for the return. We may get an invalid one when
+ // we inline invokes with multiple branches and create a Phi for the result.
+ // TODO: we could be more precise by merging the phi inputs but that requires
+ // some functionality from the reference type propagation.
+ DCHECK(return_replacement->IsPhi());
+ ReferenceTypeInfo::TypeHandle return_handle =
+ handles_->NewHandle(resolved_method->GetReturnType());
+ return_replacement->SetReferenceTypeInfo(ReferenceTypeInfo::Create(
+ return_handle, return_handle->IsFinal() /* is_exact */));
+ }
+ }
return true;
}
diff --git a/compiler/optimizing/instruction_simplifier.cc b/compiler/optimizing/instruction_simplifier.cc
index b30b6c7..d391145 100644
--- a/compiler/optimizing/instruction_simplifier.cc
+++ b/compiler/optimizing/instruction_simplifier.cc
@@ -195,16 +195,17 @@
// Returns whether doing a type test between the class of `object` against `klass` has
// a statically known outcome. The result of the test is stored in `outcome`.
static bool TypeCheckHasKnownOutcome(HLoadClass* klass, HInstruction* object, bool* outcome) {
- if (!klass->IsResolved()) {
- // If the class couldn't be resolve it's not safe to compare against it. It's
- // default type would be Top which might be wider that the actual class type
- // and thus producing wrong results.
+ DCHECK(!object->IsNullConstant()) << "Null constants should be special cased";
+ ReferenceTypeInfo obj_rti = object->GetReferenceTypeInfo();
+ ScopedObjectAccess soa(Thread::Current());
+ if (!obj_rti.IsValid()) {
+ // We run the simplifier before the reference type propagation so type info might not be
+ // available.
return false;
}
- ReferenceTypeInfo obj_rti = object->GetReferenceTypeInfo();
ReferenceTypeInfo class_rti = klass->GetLoadedClassRTI();
- ScopedObjectAccess soa(Thread::Current());
+ DCHECK(class_rti.IsValid() && class_rti.IsExact());
if (class_rti.IsSupertypeOf(obj_rti)) {
*outcome = true;
return true;
diff --git a/compiler/optimizing/nodes.cc b/compiler/optimizing/nodes.cc
index 519fa00..188cb49 100644
--- a/compiler/optimizing/nodes.cc
+++ b/compiler/optimizing/nodes.cc
@@ -1485,7 +1485,7 @@
blocks_.Put(block->GetBlockId(), nullptr);
}
-void HGraph::InlineInto(HGraph* outer_graph, HInvoke* invoke) {
+HInstruction* HGraph::InlineInto(HGraph* outer_graph, HInvoke* invoke) {
DCHECK(HasExitBlock()) << "Unimplemented scenario";
// Update the environments in this graph to have the invoke's environment
// as parent.
@@ -1510,6 +1510,7 @@
outer_graph->SetHasBoundsChecks(true);
}
+ HInstruction* return_value = nullptr;
if (GetBlocks().Size() == 3) {
// Simple case of an entry block, a body block, and an exit block.
// Put the body block's instruction into `invoke`'s block.
@@ -1524,7 +1525,8 @@
// Replace the invoke with the return value of the inlined graph.
if (last->IsReturn()) {
- invoke->ReplaceWith(last->InputAt(0));
+ return_value = last->InputAt(0);
+ invoke->ReplaceWith(return_value);
} else {
DCHECK(last->IsReturnVoid());
}
@@ -1546,7 +1548,6 @@
// Update all predecessors of the exit block (now the `to` block)
// to not `HReturn` but `HGoto` instead.
- HInstruction* return_value = nullptr;
bool returns_void = to->GetPredecessors().Get(0)->GetLastInstruction()->IsReturnVoid();
if (to->GetPredecessors().Size() == 1) {
HBasicBlock* predecessor = to->GetPredecessors().Get(0);
@@ -1680,6 +1681,8 @@
// Finally remove the invoke from the caller.
invoke->GetBlock()->RemoveInstruction(invoke);
+
+ return return_value;
}
/*
@@ -1757,11 +1760,39 @@
}
}
+void HInstruction::SetReferenceTypeInfo(ReferenceTypeInfo rti) {
+ if (kIsDebugBuild) {
+ DCHECK_EQ(GetType(), Primitive::kPrimNot);
+ ScopedObjectAccess soa(Thread::Current());
+ DCHECK(rti.IsValid()) << "Invalid RTI for " << DebugName();
+ if (IsBoundType()) {
+ // Having the test here spares us from making the method virtual just for
+ // the sake of a DCHECK.
+ ReferenceTypeInfo upper_bound_rti = AsBoundType()->GetUpperBound();
+ DCHECK(upper_bound_rti.IsSupertypeOf(rti))
+ << " upper_bound_rti: " << upper_bound_rti
+ << " rti: " << rti;
+ DCHECK(!upper_bound_rti.GetTypeHandle()->IsFinal() || rti.IsExact());
+ }
+ }
+ reference_type_info_ = rti;
+}
+
+ReferenceTypeInfo::ReferenceTypeInfo() : type_handle_(TypeHandle()), is_exact_(false) {}
+
+ReferenceTypeInfo::ReferenceTypeInfo(TypeHandle type_handle, bool is_exact)
+ : type_handle_(type_handle), is_exact_(is_exact) {
+ if (kIsDebugBuild) {
+ ScopedObjectAccess soa(Thread::Current());
+ DCHECK(IsValidHandle(type_handle));
+ }
+}
+
std::ostream& operator<<(std::ostream& os, const ReferenceTypeInfo& rhs) {
ScopedObjectAccess soa(Thread::Current());
os << "["
- << " is_top=" << rhs.IsTop()
- << " type=" << (rhs.IsTop() ? "?" : PrettyClass(rhs.GetTypeHandle().Get()))
+ << " is_valid=" << rhs.IsValid()
+ << " type=" << (!rhs.IsValid() ? "?" : PrettyClass(rhs.GetTypeHandle().Get()))
<< " is_exact=" << rhs.IsExact()
<< " ]";
return os;
diff --git a/compiler/optimizing/nodes.h b/compiler/optimizing/nodes.h
index 5c5cecc..003900c 100644
--- a/compiler/optimizing/nodes.h
+++ b/compiler/optimizing/nodes.h
@@ -210,7 +210,9 @@
void ComputeTryBlockInformation();
// Inline this graph in `outer_graph`, replacing the given `invoke` instruction.
- void InlineInto(HGraph* outer_graph, HInvoke* invoke);
+ // Returns the instruction used to replace the invoke expression or null if the
+ // invoke is for a void method.
+ HInstruction* InlineInto(HGraph* outer_graph, HInvoke* invoke);
// Need to add a couple of blocks to test if the loop body is entered and
// put deoptimization instructions, etc.
@@ -306,7 +308,12 @@
// already, it is created and inserted into the graph. This method is only for
// integral types.
HConstant* GetConstant(Primitive::Type type, int64_t value);
+
+ // TODO: This is problematic for the consistency of reference type propagation
+ // because it can be created anytime after the pass and thus it will be left
+ // with an invalid type.
HNullConstant* GetNullConstant();
+
HIntConstant* GetIntConstant(int32_t value) {
return CreateConstant(value, &cached_int_constants_);
}
@@ -1460,79 +1467,64 @@
public:
typedef Handle<mirror::Class> TypeHandle;
- static ReferenceTypeInfo Create(TypeHandle type_handle, bool is_exact)
- SHARED_REQUIRES(Locks::mutator_lock_) {
- if (type_handle->IsObjectClass()) {
- // Override the type handle to be consistent with the case when we get to
- // Top but don't have the Object class available. It avoids having to guess
- // what value the type_handle has when it's Top.
- return ReferenceTypeInfo(TypeHandle(), is_exact, true);
- } else {
- return ReferenceTypeInfo(type_handle, is_exact, false);
- }
+ static ReferenceTypeInfo Create(TypeHandle type_handle, bool is_exact) {
+ // The constructor will check that the type_handle is valid.
+ return ReferenceTypeInfo(type_handle, is_exact);
}
- static ReferenceTypeInfo CreateTop(bool is_exact) {
- return ReferenceTypeInfo(TypeHandle(), is_exact, true);
+ static ReferenceTypeInfo CreateInvalid() { return ReferenceTypeInfo(); }
+
+ static bool IsValidHandle(TypeHandle handle) SHARED_REQUIRES(Locks::mutator_lock_) {
+ return handle.GetReference() != nullptr;
}
+ bool IsValid() const SHARED_REQUIRES(Locks::mutator_lock_) {
+ return IsValidHandle(type_handle_);
+ }
bool IsExact() const { return is_exact_; }
- bool IsTop() const { return is_top_; }
+
+ bool IsObjectClass() const SHARED_REQUIRES(Locks::mutator_lock_) {
+ DCHECK(IsValid());
+ return GetTypeHandle()->IsObjectClass();
+ }
bool IsInterface() const SHARED_REQUIRES(Locks::mutator_lock_) {
- return !IsTop() && GetTypeHandle()->IsInterface();
+ DCHECK(IsValid());
+ return GetTypeHandle()->IsInterface();
}
Handle<mirror::Class> GetTypeHandle() const { return type_handle_; }
bool IsSupertypeOf(ReferenceTypeInfo rti) const SHARED_REQUIRES(Locks::mutator_lock_) {
- if (IsTop()) {
- // Top (equivalent for java.lang.Object) is supertype of anything.
- return true;
- }
- if (rti.IsTop()) {
- // If we get here `this` is not Top() so it can't be a supertype.
- return false;
- }
+ DCHECK(IsValid());
+ DCHECK(rti.IsValid());
return GetTypeHandle()->IsAssignableFrom(rti.GetTypeHandle().Get());
}
// Returns true if the type information provide the same amount of details.
// Note that it does not mean that the instructions have the same actual type
- // (e.g. tops are equal but they can be the result of a merge).
+ // (because the type can be the result of a merge).
bool IsEqual(ReferenceTypeInfo rti) SHARED_REQUIRES(Locks::mutator_lock_) {
- if (IsExact() != rti.IsExact()) {
- return false;
- }
- if (IsTop() && rti.IsTop()) {
- // `Top` means java.lang.Object, so the types are equivalent.
+ if (!IsValid() && !rti.IsValid()) {
+ // Invalid types are equal.
return true;
}
- if (IsTop() || rti.IsTop()) {
- // If only one is top or object than they are not equivalent.
- // NB: We need this extra check because the type_handle of `Top` is invalid
- // and we cannot inspect its reference.
+ if (!IsValid() || !rti.IsValid()) {
+ // One is valid, the other not.
return false;
}
-
- // Finally check the types.
- return GetTypeHandle().Get() == rti.GetTypeHandle().Get();
+ return IsExact() == rti.IsExact()
+ && GetTypeHandle().Get() == rti.GetTypeHandle().Get();
}
private:
- ReferenceTypeInfo() : ReferenceTypeInfo(TypeHandle(), false, true) {}
- ReferenceTypeInfo(TypeHandle type_handle, bool is_exact, bool is_top)
- : type_handle_(type_handle), is_exact_(is_exact), is_top_(is_top) {}
+ ReferenceTypeInfo();
+ ReferenceTypeInfo(TypeHandle type_handle, bool is_exact);
// The class of the object.
TypeHandle type_handle_;
// Whether or not the type is exact or a superclass of the actual type.
// Whether or not we have any information about this type.
bool is_exact_;
- // A true value here means that the object type should be java.lang.Object.
- // We don't have access to the corresponding mirror object every time so this
- // flag acts as a substitute. When true, the TypeHandle refers to a null
- // pointer and should not be used.
- bool is_top_;
};
std::ostream& operator<<(std::ostream& os, const ReferenceTypeInfo& rhs);
@@ -1550,7 +1542,7 @@
live_interval_(nullptr),
lifetime_position_(kNoLifetime),
side_effects_(side_effects),
- reference_type_info_(ReferenceTypeInfo::CreateTop(/* is_exact */ false)) {}
+ reference_type_info_(ReferenceTypeInfo::CreateInvalid()) {}
virtual ~HInstruction() {}
@@ -1607,10 +1599,7 @@
return false;
}
- void SetReferenceTypeInfo(ReferenceTypeInfo reference_type_info) {
- DCHECK_EQ(GetType(), Primitive::kPrimNot);
- reference_type_info_ = reference_type_info;
- }
+ void SetReferenceTypeInfo(ReferenceTypeInfo rti);
ReferenceTypeInfo GetReferenceTypeInfo() const {
DCHECK_EQ(GetType(), Primitive::kPrimNot);
@@ -3905,7 +3894,7 @@
is_referrers_class_(is_referrers_class),
dex_pc_(dex_pc),
generate_clinit_check_(false),
- loaded_class_rti_(ReferenceTypeInfo::CreateTop(/* is_exact */ false)) {
+ loaded_class_rti_(ReferenceTypeInfo::CreateInvalid()) {
SetRawInputAt(0, current_method);
}
@@ -3956,10 +3945,6 @@
loaded_class_rti_ = rti;
}
- bool IsResolved() {
- return loaded_class_rti_.IsExact();
- }
-
const DexFile& GetDexFile() { return dex_file_; }
bool NeedsDexCache() const OVERRIDE { return !is_referrers_class_; }
@@ -4202,6 +4187,8 @@
class HBoundType : public HExpression<1> {
public:
+ // Constructs an HBoundType with the given upper_bound.
+ // Ensures that the upper_bound is valid.
HBoundType(HInstruction* input, ReferenceTypeInfo upper_bound, bool upper_can_be_null)
: HExpression(Primitive::kPrimNot, SideEffects::None()),
upper_bound_(upper_bound),
@@ -4209,6 +4196,7 @@
can_be_null_(upper_can_be_null) {
DCHECK_EQ(input->GetType(), Primitive::kPrimNot);
SetRawInputAt(0, input);
+ SetReferenceTypeInfo(upper_bound_);
}
// GetUpper* should only be used in reference type propagation.
diff --git a/compiler/optimizing/reference_type_propagation.cc b/compiler/optimizing/reference_type_propagation.cc
index 9d0d412..f747fc5 100644
--- a/compiler/optimizing/reference_type_propagation.cc
+++ b/compiler/optimizing/reference_type_propagation.cc
@@ -25,13 +25,26 @@
class RTPVisitor : public HGraphDelegateVisitor {
public:
- RTPVisitor(HGraph* graph, StackHandleScopeCollection* handles)
+ RTPVisitor(HGraph* graph,
+ StackHandleScopeCollection* handles,
+ GrowableArray<HInstruction*>* worklist,
+ ReferenceTypeInfo::TypeHandle object_class_handle,
+ ReferenceTypeInfo::TypeHandle class_class_handle,
+ ReferenceTypeInfo::TypeHandle string_class_handle)
: HGraphDelegateVisitor(graph),
- handles_(handles) {}
+ handles_(handles),
+ object_class_handle_(object_class_handle),
+ class_class_handle_(class_class_handle),
+ string_class_handle_(string_class_handle),
+ worklist_(worklist) {}
+ void VisitNullConstant(HNullConstant* null_constant) OVERRIDE;
void VisitNewInstance(HNewInstance* new_instance) OVERRIDE;
void VisitLoadClass(HLoadClass* load_class) OVERRIDE;
+ void VisitClinitCheck(HClinitCheck* clinit_check) OVERRIDE;
+ void VisitLoadString(HLoadString* instr) OVERRIDE;
void VisitNewArray(HNewArray* instr) OVERRIDE;
+ void VisitParameterValue(HParameterValue* instr) OVERRIDE;
void UpdateFieldAccessTypeInfo(HInstruction* instr, const FieldInfo& info);
void SetClassAsTypeInfo(HInstruction* instr, mirror::Class* klass, bool is_exact);
void VisitInstanceFieldGet(HInstanceFieldGet* instr) OVERRIDE;
@@ -39,6 +52,8 @@
void VisitInvoke(HInvoke* instr) OVERRIDE;
void VisitArrayGet(HArrayGet* instr) OVERRIDE;
void VisitCheckCast(HCheckCast* instr) OVERRIDE;
+ void VisitNullCheck(HNullCheck* instr) OVERRIDE;
+ void VisitFakeString(HFakeString* instr) OVERRIDE;
void UpdateReferenceTypeInfo(HInstruction* instr,
uint16_t type_idx,
const DexFile& dex_file,
@@ -46,8 +61,33 @@
private:
StackHandleScopeCollection* handles_;
+ ReferenceTypeInfo::TypeHandle object_class_handle_;
+ ReferenceTypeInfo::TypeHandle class_class_handle_;
+ ReferenceTypeInfo::TypeHandle string_class_handle_;
+ GrowableArray<HInstruction*>* worklist_;
+
+ static constexpr size_t kDefaultWorklistSize = 8;
};
+ReferenceTypePropagation::ReferenceTypePropagation(HGraph* graph,
+ StackHandleScopeCollection* handles,
+ const char* name)
+ : HOptimization(graph, name),
+ handles_(handles),
+ worklist_(graph->GetArena(), kDefaultWorklistSize) {
+ ClassLinker* linker = Runtime::Current()->GetClassLinker();
+ object_class_handle_ = handles_->NewHandle(linker->GetClassRoot(ClassLinker::kJavaLangObject));
+ string_class_handle_ = handles_->NewHandle(linker->GetClassRoot(ClassLinker::kJavaLangString));
+ class_class_handle_ = handles_->NewHandle(linker->GetClassRoot(ClassLinker::kJavaLangClass));
+
+ if (kIsDebugBuild) {
+ ScopedObjectAccess soa(Thread::Current());
+ DCHECK(ReferenceTypeInfo::IsValidHandle(object_class_handle_));
+ DCHECK(ReferenceTypeInfo::IsValidHandle(class_class_handle_));
+ DCHECK(ReferenceTypeInfo::IsValidHandle(string_class_handle_));
+ }
+}
+
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.
@@ -56,24 +96,51 @@
VisitBasicBlock(it.Current());
}
ProcessWorklist();
+
+ if (kIsDebugBuild) {
+ // TODO: move this to the graph checker.
+ ScopedObjectAccess soa(Thread::Current());
+ for (HReversePostOrderIterator it(*graph_); !it.Done(); it.Advance()) {
+ HBasicBlock* block = it.Current();
+ for (HInstructionIterator iti(block->GetInstructions()); !iti.Done(); iti.Advance()) {
+ HInstruction* instr = iti.Current();
+ if (instr->GetType() == Primitive::kPrimNot) {
+ DCHECK(instr->GetReferenceTypeInfo().IsValid())
+ << "Invalid RTI for instruction: " << instr->DebugName();
+ if (instr->IsBoundType()) {
+ DCHECK(instr->AsBoundType()->GetUpperBound().IsValid());
+ } else if (instr->IsLoadClass()) {
+ DCHECK(instr->AsLoadClass()->GetReferenceTypeInfo().IsExact());
+ DCHECK(instr->AsLoadClass()->GetLoadedClassRTI().IsValid());
+ } else if (instr->IsNullCheck()) {
+ DCHECK(instr->GetReferenceTypeInfo().IsEqual(instr->InputAt(0)->GetReferenceTypeInfo()))
+ << "NullCheck " << instr->GetReferenceTypeInfo()
+ << "Input(0) " << instr->InputAt(0)->GetReferenceTypeInfo();
+ }
+ }
+ }
+ }
+ }
}
void ReferenceTypePropagation::VisitBasicBlock(HBasicBlock* block) {
- // TODO: handle other instructions that give type info
- // (array accesses)
+ RTPVisitor visitor(graph_,
+ handles_,
+ &worklist_,
+ object_class_handle_,
+ class_class_handle_,
+ string_class_handle_);
+ // Handle Phis first as there might be instructions in the same block who depend on them.
+ for (HInstructionIterator it(block->GetPhis()); !it.Done(); it.Advance()) {
+ VisitPhi(it.Current()->AsPhi());
+ }
- RTPVisitor visitor(graph_, handles_);
- // Initialize exact types first for faster convergence.
+ // Handle instructions.
for (HInstructionIterator it(block->GetInstructions()); !it.Done(); it.Advance()) {
HInstruction* instr = it.Current();
instr->Accept(&visitor);
}
- // Handle Phis.
- for (HInstructionIterator it(block->GetPhis()); !it.Done(); it.Advance()) {
- VisitPhi(it.Current()->AsPhi());
- }
-
// Add extra nodes to bound types.
BoundTypeForIfNotNull(block);
BoundTypeForIfInstanceOf(block);
@@ -91,10 +158,10 @@
ReferenceTypeInfo class_rti = load_class->GetLoadedClassRTI();
HBoundType* bound_type = new (arena) HBoundType(obj, class_rti, upper_can_be_null);
// Narrow the type as much as possible.
- if (load_class->IsResolved() && class_rti.GetTypeHandle()->IsFinal()) {
+ if (class_rti.GetTypeHandle()->IsFinal()) {
bound_type->SetReferenceTypeInfo(
ReferenceTypeInfo::Create(class_rti.GetTypeHandle(), /* is_exact */ true));
- } else if (!load_class->IsResolved() || class_rti.IsSupertypeOf(obj_rti)) {
+ } else if (obj_rti.IsValid() && class_rti.IsSupertypeOf(obj_rti)) {
bound_type->SetReferenceTypeInfo(obj_rti);
} else {
bound_type->SetReferenceTypeInfo(
@@ -185,10 +252,14 @@
if (bound_type == nullptr) {
ScopedObjectAccess soa(Thread::Current());
HInstruction* insert_point = notNullBlock->GetFirstInstruction();
- ReferenceTypeInfo object_rti = ReferenceTypeInfo::CreateTop(false);
+ ReferenceTypeInfo object_rti = ReferenceTypeInfo::Create(
+ object_class_handle_, /* is_exact */ true);
if (ShouldCreateBoundType(insert_point, obj, object_rti, nullptr, notNullBlock)) {
bound_type = new (graph_->GetArena()) HBoundType(
obj, object_rti, /* bound_can_be_null */ false);
+ if (obj->GetReferenceTypeInfo().IsValid()) {
+ bound_type->SetReferenceTypeInfo(obj->GetReferenceTypeInfo());
+ }
notNullBlock->InsertInstructionBefore(bound_type, insert_point);
} else {
// We already have a bound type on the position we would need to insert
@@ -275,11 +346,32 @@
void RTPVisitor::SetClassAsTypeInfo(HInstruction* instr,
mirror::Class* klass,
bool is_exact) {
- if (klass != nullptr) {
+ if (instr->IsInvokeStaticOrDirect() && instr->AsInvokeStaticOrDirect()->IsStringInit()) {
+ // Calls to String.<init> are replaced with a StringFactory.
+ if (kIsDebugBuild) {
+ ScopedObjectAccess soa(Thread::Current());
+ ClassLinker* cl = Runtime::Current()->GetClassLinker();
+ mirror::DexCache* dex_cache = cl->FindDexCache(instr->AsInvoke()->GetDexFile());
+ ArtMethod* method = dex_cache->GetResolvedMethod(
+ instr->AsInvoke()->GetDexMethodIndex(), cl->GetImagePointerSize());
+ DCHECK(method != nullptr);
+ mirror::Class* declaring_class = method->GetDeclaringClass();
+ DCHECK(declaring_class != nullptr);
+ DCHECK(declaring_class->IsStringClass())
+ << "Expected String class: " << PrettyDescriptor(declaring_class);
+ DCHECK(method->IsConstructor())
+ << "Expected String.<init>: " << PrettyMethod(method);
+ }
+ instr->SetReferenceTypeInfo(
+ ReferenceTypeInfo::Create(string_class_handle_, /* is_exact */ true));
+ } else if (klass != nullptr) {
ScopedObjectAccess soa(Thread::Current());
- MutableHandle<mirror::Class> handle = handles_->NewHandle(klass);
+ ReferenceTypeInfo::TypeHandle handle = handles_->NewHandle(klass);
is_exact = is_exact || klass->IsFinal();
instr->SetReferenceTypeInfo(ReferenceTypeInfo::Create(handle, is_exact));
+ } else {
+ instr->SetReferenceTypeInfo(
+ ReferenceTypeInfo::Create(object_class_handle_, /* is_exact */ false));
}
}
@@ -295,6 +387,13 @@
SetClassAsTypeInfo(instr, dex_cache->GetResolvedType(type_idx), is_exact);
}
+void RTPVisitor::VisitNullConstant(HNullConstant* instr) {
+ // TODO: The null constant could be bound contextually (e.g. based on return statements)
+ // to a more precise type.
+ instr->SetReferenceTypeInfo(
+ ReferenceTypeInfo::Create(object_class_handle_, /* is_exact */ false));
+}
+
void RTPVisitor::VisitNewInstance(HNewInstance* instr) {
UpdateReferenceTypeInfo(instr, instr->GetTypeIndex(), instr->GetDexFile(), /* is_exact */ true);
}
@@ -303,6 +402,13 @@
UpdateReferenceTypeInfo(instr, instr->GetTypeIndex(), instr->GetDexFile(), /* is_exact */ true);
}
+void RTPVisitor::VisitParameterValue(HParameterValue* instr) {
+ if (instr->GetType() == Primitive::kPrimNot) {
+ // TODO: parse the signature and add precise types for the parameters.
+ SetClassAsTypeInfo(instr, nullptr, /* is_exact */ false);
+ }
+}
+
void RTPVisitor::UpdateFieldAccessTypeInfo(HInstruction* instr,
const FieldInfo& info) {
// The field index is unknown only during tests.
@@ -314,10 +420,10 @@
ClassLinker* cl = Runtime::Current()->GetClassLinker();
mirror::DexCache* dex_cache = cl->FindDexCache(info.GetDexFile());
ArtField* field = cl->GetResolvedField(info.GetFieldIndex(), dex_cache);
- if (field != nullptr) {
- mirror::Class* klass = field->GetType<false>();
- SetClassAsTypeInfo(instr, klass, /* is_exact */ false);
- }
+ // TODO: There are certain cases where we can't resolve the field.
+ // b/21914925 is open to keep track of a repro case for this issue.
+ mirror::Class* klass = (field == nullptr) ? nullptr : field->GetType<false>();
+ SetClassAsTypeInfo(instr, klass, /* is_exact */ false);
}
void RTPVisitor::VisitInstanceFieldGet(HInstanceFieldGet* instr) {
@@ -334,12 +440,29 @@
Runtime::Current()->GetClassLinker()->FindDexCache(instr->GetDexFile());
// Get type from dex cache assuming it was populated by the verifier.
mirror::Class* resolved_class = dex_cache->GetResolvedType(instr->GetTypeIndex());
- if (resolved_class != nullptr) {
- Handle<mirror::Class> handle = handles_->NewHandle(resolved_class);
- instr->SetLoadedClassRTI(ReferenceTypeInfo::Create(handle, /* is_exact */ true));
- }
- Handle<mirror::Class> class_handle = handles_->NewHandle(mirror::Class::GetJavaLangClass());
- instr->SetReferenceTypeInfo(ReferenceTypeInfo::Create(class_handle, /* is_exact */ true));
+ DCHECK(resolved_class != nullptr);
+ ReferenceTypeInfo::TypeHandle handle = handles_->NewHandle(resolved_class);
+ instr->SetLoadedClassRTI(ReferenceTypeInfo::Create(handle, /* is_exact */ true));
+ instr->SetReferenceTypeInfo(ReferenceTypeInfo::Create(class_class_handle_, /* is_exact */ true));
+}
+
+void RTPVisitor::VisitClinitCheck(HClinitCheck* instr) {
+ instr->SetReferenceTypeInfo(instr->InputAt(0)->GetReferenceTypeInfo());
+}
+
+void RTPVisitor::VisitLoadString(HLoadString* instr) {
+ instr->SetReferenceTypeInfo(ReferenceTypeInfo::Create(string_class_handle_, /* is_exact */ true));
+}
+
+void RTPVisitor::VisitNullCheck(HNullCheck* instr) {
+ ScopedObjectAccess soa(Thread::Current());
+ ReferenceTypeInfo parent_rti = instr->InputAt(0)->GetReferenceTypeInfo();
+ DCHECK(parent_rti.IsValid());
+ instr->SetReferenceTypeInfo(parent_rti);
+}
+
+void RTPVisitor::VisitFakeString(HFakeString* instr) {
+ instr->SetReferenceTypeInfo(ReferenceTypeInfo::Create(string_class_handle_, /* is_exact */ true));
}
void RTPVisitor::VisitCheckCast(HCheckCast* check_cast) {
@@ -395,29 +518,54 @@
ReferenceTypeInfo ReferenceTypePropagation::MergeTypes(const ReferenceTypeInfo& a,
const ReferenceTypeInfo& b) {
- bool is_exact = a.IsExact() && b.IsExact();
- bool is_top = a.IsTop() || b.IsTop();
- Handle<mirror::Class> type_handle;
-
- if (!is_top) {
- if (a.GetTypeHandle().Get() == b.GetTypeHandle().Get()) {
- type_handle = a.GetTypeHandle();
- } else if (a.IsSupertypeOf(b)) {
- type_handle = a.GetTypeHandle();
- is_exact = false;
- } else if (b.IsSupertypeOf(a)) {
- type_handle = b.GetTypeHandle();
- is_exact = false;
- } else {
- // TODO: Find a common super class.
- is_top = true;
- is_exact = false;
- }
+ if (!b.IsValid()) {
+ return a;
+ }
+ if (!a.IsValid()) {
+ return b;
}
- return is_top
- ? ReferenceTypeInfo::CreateTop(is_exact)
- : ReferenceTypeInfo::Create(type_handle, is_exact);
+ bool is_exact = a.IsExact() && b.IsExact();
+ Handle<mirror::Class> type_handle;
+
+ if (a.GetTypeHandle().Get() == b.GetTypeHandle().Get()) {
+ type_handle = a.GetTypeHandle();
+ } else if (a.IsSupertypeOf(b)) {
+ type_handle = a.GetTypeHandle();
+ is_exact = false;
+ } else if (b.IsSupertypeOf(a)) {
+ type_handle = b.GetTypeHandle();
+ is_exact = false;
+ } else {
+ // TODO: Find the first common super class.
+ type_handle = object_class_handle_;
+ is_exact = false;
+ }
+
+ return ReferenceTypeInfo::Create(type_handle, is_exact);
+}
+
+static void UpdateArrayGet(HArrayGet* instr,
+ StackHandleScopeCollection* handles,
+ ReferenceTypeInfo::TypeHandle object_class_handle)
+ SHARED_REQUIRES(Locks::mutator_lock_) {
+ DCHECK_EQ(Primitive::kPrimNot, instr->GetType());
+
+ ReferenceTypeInfo parent_rti = instr->InputAt(0)->GetReferenceTypeInfo();
+ DCHECK(parent_rti.IsValid());
+
+ Handle<mirror::Class> handle = parent_rti.GetTypeHandle();
+ if (handle->IsObjectArrayClass()) {
+ ReferenceTypeInfo::TypeHandle component_handle = handles->NewHandle(handle->GetComponentType());
+ instr->SetReferenceTypeInfo(
+ ReferenceTypeInfo::Create(component_handle, /* is_exact */ false));
+ } else {
+ // We don't know what the parent actually is, so we fallback to object.
+ instr->SetReferenceTypeInfo(
+ ReferenceTypeInfo::Create(object_class_handle, /* is_exact */ false));
+ }
+
+ return;
}
bool ReferenceTypePropagation::UpdateReferenceTypeInfo(HInstruction* instr) {
@@ -428,6 +576,15 @@
UpdateBoundType(instr->AsBoundType());
} else if (instr->IsPhi()) {
UpdatePhi(instr->AsPhi());
+ } else if (instr->IsNullCheck()) {
+ ReferenceTypeInfo parent_rti = instr->InputAt(0)->GetReferenceTypeInfo();
+ if (parent_rti.IsValid()) {
+ instr->SetReferenceTypeInfo(parent_rti);
+ }
+ } else if (instr->IsArrayGet()) {
+ // 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 {
LOG(FATAL) << "Invalid instruction (should not get here)";
}
@@ -445,28 +602,28 @@
mirror::DexCache* dex_cache = cl->FindDexCache(instr->GetDexFile());
ArtMethod* method = dex_cache->GetResolvedMethod(
instr->GetDexMethodIndex(), cl->GetImagePointerSize());
- if (method != nullptr) {
- mirror::Class* klass = method->GetReturnType(false);
- SetClassAsTypeInfo(instr, klass, /* is_exact */ false);
- }
+ mirror::Class* klass = (method == nullptr) ? nullptr : method->GetReturnType(false);
+ SetClassAsTypeInfo(instr, klass, /* is_exact */ false);
}
void RTPVisitor::VisitArrayGet(HArrayGet* instr) {
if (instr->GetType() != Primitive::kPrimNot) {
return;
}
-
- HInstruction* parent = instr->InputAt(0);
ScopedObjectAccess soa(Thread::Current());
- Handle<mirror::Class> handle = parent->GetReferenceTypeInfo().GetTypeHandle();
- if (handle.GetReference() != nullptr && handle->IsObjectArrayClass()) {
- SetClassAsTypeInfo(instr, handle->GetComponentType(), /* is_exact */ false);
+ UpdateArrayGet(instr, handles_, object_class_handle_);
+ if (!instr->GetReferenceTypeInfo().IsValid()) {
+ worklist_->Add(instr);
}
}
void ReferenceTypePropagation::UpdateBoundType(HBoundType* instr) {
ReferenceTypeInfo new_rti = instr->InputAt(0)->GetReferenceTypeInfo();
- // Be sure that we don't go over the bounded type.
+ if (!new_rti.IsValid()) {
+ return; // No new info yet.
+ }
+
+ // Make sure that we don't go over the bounded type.
ReferenceTypeInfo upper_bound_rti = instr->GetUpperBound();
if (!upper_bound_rti.IsSupertypeOf(new_rti)) {
new_rti = upper_bound_rti;
@@ -476,14 +633,14 @@
void ReferenceTypePropagation::UpdatePhi(HPhi* instr) {
ReferenceTypeInfo new_rti = instr->InputAt(0)->GetReferenceTypeInfo();
- if (new_rti.IsTop() && !new_rti.IsExact()) {
- // Early return if we are Top and inexact.
+ if (new_rti.IsValid() && new_rti.IsObjectClass() && !new_rti.IsExact()) {
+ // Early return if we are Object and inexact.
instr->SetReferenceTypeInfo(new_rti);
return;
}
for (size_t i = 1; i < instr->InputCount(); i++) {
new_rti = MergeTypes(new_rti, instr->InputAt(i)->GetReferenceTypeInfo());
- if (new_rti.IsTop()) {
+ if (new_rti.IsValid() && new_rti.IsObjectClass()) {
if (!new_rti.IsExact()) {
break;
} else {
@@ -497,7 +654,14 @@
// Re-computes and updates the nullability of the instruction. Returns whether or
// not the nullability was changed.
bool ReferenceTypePropagation::UpdateNullability(HInstruction* instr) {
- DCHECK(instr->IsPhi() || instr->IsBoundType());
+ DCHECK(instr->IsPhi()
+ || instr->IsBoundType()
+ || instr->IsNullCheck()
+ || instr->IsArrayGet());
+
+ if (!instr->IsPhi() && !instr->IsBoundType()) {
+ return false;
+ }
bool existing_can_be_null = instr->CanBeNull();
if (instr->IsPhi()) {
@@ -527,14 +691,18 @@
}
void ReferenceTypePropagation::AddToWorklist(HInstruction* instruction) {
- DCHECK_EQ(instruction->GetType(), Primitive::kPrimNot) << instruction->GetType();
+ DCHECK_EQ(instruction->GetType(), Primitive::kPrimNot)
+ << instruction->DebugName() << ":" << instruction->GetType();
worklist_.Add(instruction);
}
void ReferenceTypePropagation::AddDependentInstructionsToWorklist(HInstruction* instruction) {
for (HUseIterator<HInstruction*> it(instruction->GetUses()); !it.Done(); it.Advance()) {
HInstruction* user = it.Current()->GetUser();
- if (user->IsPhi() || user->IsBoundType()) {
+ if (user->IsPhi()
+ || user->IsBoundType()
+ || user->IsNullCheck()
+ || (user->IsArrayGet() && (user->GetType() == Primitive::kPrimNot))) {
AddToWorklist(user);
}
}
diff --git a/compiler/optimizing/reference_type_propagation.h b/compiler/optimizing/reference_type_propagation.h
index 32f5e09..14d4a82 100644
--- a/compiler/optimizing/reference_type_propagation.h
+++ b/compiler/optimizing/reference_type_propagation.h
@@ -32,10 +32,7 @@
public:
ReferenceTypePropagation(HGraph* graph,
StackHandleScopeCollection* handles,
- const char* name = kReferenceTypePropagationPassName)
- : HOptimization(graph, name),
- handles_(handles),
- worklist_(graph->GetArena(), kDefaultWorklistSize) {}
+ const char* name = kReferenceTypePropagationPassName);
void Run() OVERRIDE;
@@ -62,6 +59,10 @@
GrowableArray<HInstruction*> worklist_;
+ ReferenceTypeInfo::TypeHandle object_class_handle_;
+ ReferenceTypeInfo::TypeHandle class_class_handle_;
+ ReferenceTypeInfo::TypeHandle string_class_handle_;
+
static constexpr size_t kDefaultWorklistSize = 8;
DISALLOW_COPY_AND_ASSIGN(ReferenceTypePropagation);