[turbofan] Osr value typing + dynamic type checks on entry.

src/compiler/typer.cc

 // 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.
 
 #include "src/compiler/typer.h"
 
 #include <iomanip>
 
 #include "src/base/flags.h"
 #include "src/bootstrapper.h"
@@ skipping 532 matching lines @@
 Type* Typer::Visitor::TypeIfException(Node* node) {
   return Type::NonInternal();
 }
 
 // Common operators.
 
 Type* Typer::Visitor::TypeParameter(Node* node) { return Type::Any(); }
 
 Type* Typer::Visitor::TypeOsrValue(Node* node) { return Type::Any(); }
 
+Type* Typer::Visitor::TypeOsrGuard(Node* node) {
+  switch (OsrGuardTypeOf(node->op())) {
+    case OsrGuardType::kUninitialized:
+      return Type::None();
+    case OsrGuardType::kSignedSmall:
+      return Type::SignedSmall();
+    case OsrGuardType::kAny:
+      return Type::Any();
+  }
+  UNREACHABLE();
+  return nullptr;
+}
+
 Type* Typer::Visitor::TypeRetain(Node* node) {
   UNREACHABLE();
   return nullptr;
 }
 
 Type* Typer::Visitor::TypeInt32Constant(Node* node) {
   double number = OpParameter<int32_t>(node);
   return Type::Intersect(Type::Range(number, number, zone()),
                          Type::Integral32(), zone());
 }
@@ skipping 1153 matching lines @@
 Type* Typer::Visitor::TypeConstant(Handle<Object> value) {
   if (Type::IsInteger(*value)) {
     return Type::Range(value->Number(), value->Number(), zone());
   }
   return Type::Constant(value, zone());
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8