[turbofan] Add support for storing to double fields.

src/compiler/typer.cc

Index: src/compiler/typer.cc
diff --git a/src/compiler/typer.cc b/src/compiler/typer.cc
index 6c80446ce921da7e1906cd4dfe3e74e2bca6ee61..ea20cec83fdbfd2c8a26c483b28c2634e82c63c4 100644
--- a/src/compiler/typer.cc
+++ b/src/compiler/typer.cc
@@ -557,6 +557,13 @@ Type* Typer::Visitor::TypeEffectSet(Node* node) {
 }
 
 
+Type* Typer::Visitor::TypeGuard(Node* node) {
+  Type* input_type = Operand(node, 0);
+  Type* guard_type = OpParameter<Type*>(node);
+  return Type::Intersect(input_type, guard_type, zone());
+}
+
+
 Type* Typer::Visitor::TypeBeginRegion(Node* node) {
   UNREACHABLE();
   return nullptr;
@@ -1786,6 +1793,15 @@ Type* Typer::Visitor::TypeStoreElement(Node* node) {
 }
 
 
+Type* Typer::Visitor::TypeObjectIsNumber(Node* node) {
+  Type* arg = Operand(node, 0);
+  if (arg->Is(Type::None())) return Type::None();
+  if (arg->Is(Type::Number())) return typer_->singleton_true_;
+  if (!arg->Maybe(Type::Number())) return typer_->singleton_false_;
+  return Type::Boolean();
+}
+
+
 Type* Typer::Visitor::TypeObjectIsSmi(Node* node) {
   Type* arg = Operand(node, 0);
   if (arg->Is(Type::None())) return Type::None();