1 files changed, 62 insertions, 7 deletions

diff --git a/compiler/optimizing/nodes.h b/compiler/optimizing/nodes.h
index eebc49c991..e3f4d8f035 100644
--- a/compiler/optimizing/nodes.h
+++ b/compiler/optimizing/nodes.h
@@ -333,7 +333,8 @@ class HGraph : public ArenaObject<kArenaAllocGraph> {
         cached_double_constants_(std::less<int64_t>(), arena->Adapter(kArenaAllocConstantsMap)),
         cached_current_method_(nullptr),
         inexact_object_rti_(ReferenceTypeInfo::CreateInvalid()),
-        osr_(osr) {
+        osr_(osr),
+        cha_single_implementation_list_(arena->Adapter(kArenaAllocCHA)) {
     blocks_.reserve(kDefaultNumberOfBlocks);
   }
 
@@ -536,6 +537,20 @@ class HGraph : public ArenaObject<kArenaAllocGraph> {
 
   bool IsCompilingOsr() const { return osr_; }
 
+  ArenaSet<ArtMethod*>& GetCHASingleImplementationList() {
+    return cha_single_implementation_list_;
+  }
+
+  void AddCHASingleImplementationDependency(ArtMethod* method) {
+    cha_single_implementation_list_.insert(method);
+  }
+
+  bool HasShouldDeoptimizeFlag() const {
+    // TODO: if all CHA guards can be eliminated, there is no need for the flag
+    // even if cha_single_implementation_list_ is not empty.
+    return !cha_single_implementation_list_.empty();
+  }
+
   bool HasTryCatch() const { return has_try_catch_; }
   void SetHasTryCatch(bool value) { has_try_catch_ = value; }
 
@@ -672,6 +687,9 @@ class HGraph : public ArenaObject<kArenaAllocGraph> {
   // compiled code entries which the interpreter can directly jump to.
   const bool osr_;
 
+  // List of methods that are assumed to have single implementation.
+  ArenaSet<ArtMethod*> cha_single_implementation_list_;
+
   friend class SsaBuilder;           // For caching constants.
   friend class SsaLivenessAnalysis;  // For the linear order.
   friend class HInliner;             // For the reverse post order.
@@ -1240,6 +1258,7 @@ class HLoopInformationOutwardIterator : public ValueObject {
   M(ClinitCheck, Instruction)                                           \
   M(Compare, BinaryOperation)                                           \
   M(CurrentMethod, Instruction)                                         \
+  M(ShouldDeoptimizeFlag, Instruction)                                  \
   M(Deoptimize, Instruction)                                            \
   M(Div, BinaryOperation)                                               \
   M(DivZeroCheck, Instruction)                                          \
@@ -2072,6 +2091,8 @@ class HInstruction : public ArenaObject<kArenaAllocInstruction> {
 #undef INSTRUCTION_TYPE_CHECK
 
   // Returns whether the instruction can be moved within the graph.
+  // TODO: this method is used by LICM and GVN with possibly different
+  //       meanings? split and rename?
   virtual bool CanBeMoved() const { return false; }
 
   // Returns whether the two instructions are of the same kind.
@@ -2873,6 +2894,27 @@ class HDeoptimize FINAL : public HTemplateInstruction<1> {
   DISALLOW_COPY_AND_ASSIGN(HDeoptimize);
 };
 
+// Represents a should_deoptimize flag. Currently used for CHA-based devirtualization.
+// The compiled code checks this flag value in a guard before devirtualized call and
+// if it's true, starts to do deoptimization.
+// It has a 4-byte slot on stack.
+// TODO: allocate a register for this flag.
+class HShouldDeoptimizeFlag FINAL : public HExpression<0> {
+ public:
+  // TODO: use SideEffects to aid eliminating some CHA guards.
+  explicit HShouldDeoptimizeFlag(uint32_t dex_pc)
+      : HExpression(Primitive::kPrimInt, SideEffects::None(), dex_pc) {
+  }
+
+  // We don't eliminate CHA guards yet.
+  bool CanBeMoved() const OVERRIDE { return false; }
+
+  DECLARE_INSTRUCTION(ShouldDeoptimizeFlag);
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(HShouldDeoptimizeFlag);
+};
+
 // Represents the ArtMethod that was passed as a first argument to
 // the method. It is used by instructions that depend on it, like
 // instructions that work with the dex cache.
@@ -3789,7 +3831,7 @@ class HInvoke : public HInstruction {
 
   bool CanThrow() const OVERRIDE { return GetPackedFlag<kFlagCanThrow>(); }
 
-  bool CanBeMoved() const OVERRIDE { return IsIntrinsic(); }
+  bool CanBeMoved() const OVERRIDE { return IsIntrinsic() && !DoesAnyWrite(); }
 
   bool InstructionDataEquals(const HInstruction* other) const OVERRIDE {
     return intrinsic_ != Intrinsics::kNone && intrinsic_ == other->AsInvoke()->intrinsic_;
@@ -4181,6 +4223,19 @@ class HInvokeVirtual FINAL : public HInvoke {
                 kVirtual),
         vtable_index_(vtable_index) {}
 
+  bool CanBeNull() const OVERRIDE {
+    switch (GetIntrinsic()) {
+      case Intrinsics::kThreadCurrentThread:
+      case Intrinsics::kStringBufferAppend:
+      case Intrinsics::kStringBufferToString:
+      case Intrinsics::kStringBuilderAppend:
+      case Intrinsics::kStringBuilderToString:
+        return false;
+      default:
+        return HInvoke::CanBeNull();
+    }
+  }
+
   bool CanDoImplicitNullCheckOn(HInstruction* obj) const OVERRIDE {
     // TODO: Add implicit null checks in intrinsics.
     return (obj == InputAt(0)) && !GetLocations()->Intrinsified();
@@ -5698,7 +5753,7 @@ class HLoadString FINAL : public HInstruction {
   };
 
   HLoadString(HCurrentMethod* current_method,
-              uint32_t string_index,
+              dex::StringIndex string_index,
               const DexFile& dex_file,
               uint32_t dex_pc)
       : HInstruction(SideEffectsForArchRuntimeCalls(), dex_pc),
@@ -5717,7 +5772,7 @@ class HLoadString FINAL : public HInstruction {
 
   void SetLoadKindWithStringReference(LoadKind load_kind,
                                       const DexFile& dex_file,
-                                      uint32_t string_index) {
+                                      dex::StringIndex string_index) {
     DCHECK(HasStringReference(load_kind));
     load_data_.dex_file_ = &dex_file;
     string_index_ = string_index;
@@ -5730,7 +5785,7 @@ class HLoadString FINAL : public HInstruction {
 
   const DexFile& GetDexFile() const;
 
-  uint32_t GetStringIndex() const {
+  dex::StringIndex GetStringIndex() const {
     DCHECK(HasStringReference(GetLoadKind()) || /* For slow paths. */ !IsInDexCache());
     return string_index_;
   }
@@ -5744,7 +5799,7 @@ class HLoadString FINAL : public HInstruction {
 
   bool InstructionDataEquals(const HInstruction* other) const OVERRIDE;
 
-  size_t ComputeHashCode() const OVERRIDE { return string_index_; }
+  size_t ComputeHashCode() const OVERRIDE { return string_index_.index_; }
 
   // Will call the runtime if we need to load the string through
   // the dex cache and the string is not guaranteed to be there yet.
@@ -5823,7 +5878,7 @@ class HLoadString FINAL : public HInstruction {
 
   // String index serves also as the hash code and it's also needed for slow-paths,
   // so it must not be overwritten with other load data.
-  uint32_t string_index_;
+  dex::StringIndex string_index_;
 
   union {
     const DexFile* dex_file_;            // For string reference.