Ensure that all goto instructions have deoptimization target.

runtime/vm/intermediate_language.h

Index: runtime/vm/intermediate_language.h
diff --git a/runtime/vm/intermediate_language.h b/runtime/vm/intermediate_language.h
index 94f2b5d86ab0e007b75012fbf579c4fe68c712db..828b19f4464860c8432280cef6058b59d58e0f6c 100644
--- a/runtime/vm/intermediate_language.h
+++ b/runtime/vm/intermediate_language.h
@@ -535,7 +535,7 @@ class Instruction : public ZoneAllocated {
   virtual Tag tag() const = 0;
 
   intptr_t deopt_id() const {
-    ASSERT(CanDeoptimize());
+    ASSERT(CanDeoptimize() || CanBeDeoptimizationTarget());
     return deopt_id_;
   }
 
@@ -728,6 +728,18 @@ FOR_EACH_INSTRUCTION(INSTRUCTION_TYPE_CHECK)
     return false;
   }
 
+  virtual void InheritDeoptTarget(Instruction* other);
+
+  bool NeedsEnvironment() const {
+    return CanDeoptimize() || CanBeDeoptimizationTarget();
+  }
+
+  virtual bool CanBeDeoptimizationTarget() const {
+    return false;
+  }
+
+  void InheritDeoptTargetAfter(Instruction* other);
+
  protected:
   // Fetch deopt id without checking if this computation can deoptimize.
   intptr_t GetDeoptId() const {
@@ -760,6 +772,11 @@ FOR_EACH_INSTRUCTION(INSTRUCTION_TYPE_CHECK)
   friend class LoadIndexedInstr;
   friend class StoreIndexedInstr;
   friend class StoreInstanceFieldInstr;
+  friend class ControlInstruction;
+  friend class ComparisonInstr;
+  friend class TargetEntryInstr;
+  friend class JoinEntryInstr;
+  friend class InstanceOfInstr;
 
   virtual void RawSetInputAt(intptr_t i, Value* value) = 0;
 
@@ -981,6 +998,12 @@ class BlockEntryInstr : public Instruction {
 
   virtual intptr_t ArgumentCount() const { return 0; }
 
+  virtual bool CanBeDeoptimizationTarget() const {
+    // BlockEntry environment is copied to Goto and Branch instructions
+    // when we insert new blocks targeting this block.
+    return true;
+  }
+
   virtual bool CanDeoptimize() const { return false; }
 
   virtual bool HasSideEffect() const { return false; }
@@ -1653,6 +1676,12 @@ class ReturnInstr : public TemplateInstruction<1> {
   intptr_t token_pos() const { return token_pos_; }
   Value* value() const { return inputs_[0]; }
 
+  virtual bool CanBeDeoptimizationTarget() const {
+    // Return instruction might turn into a Goto instruction after inlining.
+    // Every Goto must have an environment.
+    return true;
+  }
+
   virtual bool CanDeoptimize() const { return false; }
 
   virtual bool HasSideEffect() const { return false; }
@@ -1721,6 +1750,12 @@ class GotoInstr : public TemplateInstruction<0> {
   virtual intptr_t SuccessorCount() const;
   virtual BlockEntryInstr* SuccessorAt(intptr_t index) const;
 
+  virtual bool CanBeDeoptimizationTarget() const {
+    // Goto instruction can be used as a deoptimization target when LICM
+    // hoists instructions out of the loop.
+    return true;
+  }
+
   virtual bool CanDeoptimize() const { return false; }
 
   virtual bool HasSideEffect() const { return false; }
@@ -1789,6 +1824,7 @@ class BranchInstr : public ControlInstruction {
   intptr_t InputCount() const;
   Value* InputAt(intptr_t i) const;
   virtual bool CanDeoptimize() const;
+  virtual bool CanBeDeoptimizationTarget() const;
 
   virtual bool HasSideEffect() const;
 
@@ -1825,6 +1861,8 @@ class BranchInstr : public ControlInstruction {
     return constrained_type_;
   }
 
+  virtual void InheritDeoptTarget(Instruction* other);
+
  private:
   virtual void RawSetInputAt(intptr_t i, Value* value);
 
@@ -2422,6 +2460,10 @@ class ComparisonInstr : public TemplateDefinition<2> {
   virtual void EmitBranchCode(FlowGraphCompiler* compiler,
                               BranchInstr* branch) = 0;
 
+  void SetDeoptId(intptr_t deopt_id) {
+    deopt_id_ = deopt_id;
+  }
+
  protected:
   Token::Kind kind_;
 };
@@ -2450,6 +2492,11 @@ inline bool BranchInstr::CanDeoptimize() const {
 }
 
 
+inline bool BranchInstr::CanBeDeoptimizationTarget() const {
+  return comparison()->CanBeDeoptimizationTarget();
+}
+
+
 inline bool BranchInstr::HasSideEffect() const {
   return comparison()->HasSideEffect();
 }
@@ -2486,6 +2533,11 @@ class StrictCompareInstr : public ComparisonInstr {
 
   virtual void PrintOperandsTo(BufferFormatter* f) const;
 
+  virtual bool CanBeDeoptimizationTarget() const {
+    // StrictCompare can be merged into Branch and thus needs an environment.
+    return true;
+  }
+
   virtual bool CanDeoptimize() const { return false; }
 
   virtual bool HasSideEffect() const { return false; }
@@ -2533,6 +2585,7 @@ class EqualityCompareInstr : public ComparisonInstr {
   bool HasICData() const {
     return (ic_data() != NULL) && !ic_data()->IsNull();
   }
+  void set_ic_data(const ICData* value) { ic_data_ = value; }
 
   intptr_t token_pos() const { return token_pos_; }
 
@@ -2603,6 +2656,7 @@ class RelationalOpInstr : public ComparisonInstr {
   bool HasICData() const {
     return (ic_data() != NULL) && !ic_data()->IsNull();
   }
+  void set_ic_data(const ICData* value) { ic_data_ = value; }
 
   intptr_t token_pos() const { return token_pos_; }
 
@@ -3110,7 +3164,8 @@ class InstanceOfInstr : public TemplateDefinition<3> {
                   Value* instantiator,
                   Value* instantiator_type_arguments,
                   const AbstractType& type,
-                  bool negate_result)
+                  bool negate_result,
+                  intptr_t deopt_id)
       : token_pos_(token_pos),
         type_(type),
         negate_result_(negate_result) {
@@ -3118,6 +3173,7 @@ class InstanceOfInstr : public TemplateDefinition<3> {
     SetInputAt(0, value);
     SetInputAt(1, instantiator);
     SetInputAt(2, instantiator_type_arguments);
+    deopt_id_ = deopt_id;
   }
 
   DECLARE_INSTRUCTION(InstanceOf)