Refine expression typing, esp. by propagating range information.

src/compiler/typer.h

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_COMPILER_TYPER_H_
 #define V8_COMPILER_TYPER_H_
 
 #include "src/v8.h"
 
 #include "src/compiler/graph.h"
@@ skipping 18 matching lines @@
   Zone* zone() { return zone_; }
   Isolate* isolate() { return zone_->isolate(); }
 
  private:
   class Visitor;
   class RunVisitor;
   class NarrowVisitor;
   class WidenVisitor;
 
   Zone* zone_;
+  Type* negative_signed32;
+  Type* non_negative_signed32;
+  Type* undefined_or_null;
+  Type* singleton_false;
+  Type* singleton_true;
+  Type* singleton_zero;
+  Type* singleton_one;
+  Type* zero_or_one;
+  Type* zeroish;
+  Type* falsish;
+  Type* integer;
   Type* number_fun0_;
   Type* number_fun1_;
   Type* number_fun2_;
   Type* weakint_fun1_;
   Type* imul_fun_;
   Type* random_fun_;
   Type* array_buffer_fun_;
   Type* int8_array_fun_;
   Type* int16_array_fun_;
   Type* int32_array_fun_;
   Type* uint8_array_fun_;
   Type* uint16_array_fun_;
   Type* uint32_array_fun_;
   Type* float32_array_fun_;
   Type* float64_array_fun_;
 };
 }
 }
 }  // namespace v8::internal::compiler
 
 #endif  // V8_COMPILER_TYPER_H_