Cleanup: Make CheckClassId instruction more general so it

runtime/vm/intermediate_language.h

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #ifndef RUNTIME_VM_INTERMEDIATE_LANGUAGE_H_
 #define RUNTIME_VM_INTERMEDIATE_LANGUAGE_H_
 
 #include "vm/allocation.h"
 #include "vm/ast.h"
 #include "vm/growable_array.h"
@@ skipping 539 matching lines @@
 #endif  // !PRODUCT
 
 
 // Represents a range of class-ids for use in class checks and polymorphic
 // dispatches.
 struct CidRange : public ZoneAllocated {
   CidRange(const CidRange& o)
       : ZoneAllocated(), cid_start(o.cid_start), cid_end(o.cid_end) {}
   CidRange(intptr_t cid_start_arg, intptr_t cid_end_arg)
       : cid_start(cid_start_arg), cid_end(cid_end_arg) {}
+
+  bool IsSingleCid() const { return cid_start == cid_end; }
+  bool Contains(intptr_t cid) { return cid_start <= cid && cid <= cid_end; }
+
   intptr_t cid_start;
   intptr_t cid_end;

[kustermann, 2017/05/18 09:59:45]

Maybe consider removing the "cid_" prefixes, it's implied by the CidRange
struct.

[erikcorry, 2017/05/18 14:25:30]

I took a look at this, and the word "CidRange" is not usually visible near the
word cid_start or cid_end, so I think this would make the code harder to read.

 };
 
 
 // Together with CidRange, this represents a mapping from a range of class-ids
 // to a method for a given selector (method name).  Also can contain an
 // indication of how frequently a given method has been called at a call site.
 // This information can be harvested from the inline caches (ICs).
 struct TargetInfo : public CidRange {
   TargetInfo(intptr_t cid_start_arg,
              intptr_t cid_end_arg,
@@ skipping 7149 matching lines @@
  private:
   const TokenPosition token_pos_;
   bool licm_hoisted_;
 
   DISALLOW_COPY_AND_ASSIGN(CheckSmiInstr);
 };
 
 
 class CheckClassIdInstr : public TemplateInstruction<1, NoThrow> {
  public:
-  CheckClassIdInstr(Value* value, intptr_t cid, intptr_t deopt_id)
-      : TemplateInstruction(deopt_id), cid_(cid) {
+  CheckClassIdInstr(Value* value, CidRange cids, intptr_t deopt_id)
+      : TemplateInstruction(deopt_id), cids_(cids) {
     SetInputAt(0, value);
   }
 
   Value* value() const { return inputs_[0]; }
-  intptr_t cid() const { return cid_; }
+  const CidRange& cids() const { return cids_; }
 
   DECLARE_INSTRUCTION(CheckClassId)
 
   virtual bool ComputeCanDeoptimize() const { return true; }
 
   virtual Instruction* Canonicalize(FlowGraph* flow_graph);
 
   virtual bool AllowsCSE() const { return true; }
   virtual EffectSet Dependencies() const;
   virtual EffectSet Effects() const { return EffectSet::None(); }
   virtual bool AttributesEqual(Instruction* other) const { return true; }
 
   PRINT_OPERANDS_TO_SUPPORT
 
  private:
-  intptr_t cid_;
+  bool Contains(intptr_t cid) const;
+
+  CidRange cids_;
 
   DISALLOW_COPY_AND_ASSIGN(CheckClassIdInstr);
 };
 
 
 class CheckArrayBoundInstr : public TemplateInstruction<2, NoThrow, Pure> {
  public:
   CheckArrayBoundInstr(Value* length, Value* index, intptr_t deopt_id)
       : TemplateInstruction(deopt_id),
         generalized_(false),
@@ skipping 406 matching lines @@
   LocationSummary* Name::MakeLocationSummary(Zone* zone, bool opt) const {     \
     UNIMPLEMENTED();                                                           \
     return NULL;                                                               \
   }                                                                            \
   void Name::EmitNativeCode(FlowGraphCompiler* compiler) { UNIMPLEMENTED(); }
 
 
 }  // namespace dart
 
 #endif  // RUNTIME_VM_INTERMEDIATE_LANGUAGE_H_