[turbofan] Optimize string "length" property access based on types.

src/compiler/access-builder.cc

Index: src/compiler/access-builder.cc
diff --git a/src/compiler/access-builder.cc b/src/compiler/access-builder.cc
index 5046fef5935c4b2ea66565491f3d7f272cfb4b44..a0225aa48987ef0942ac7a65d039538cec2fc661 100644
--- a/src/compiler/access-builder.cc
+++ b/src/compiler/access-builder.cc
@@ -115,7 +115,9 @@ FieldAccess AccessBuilder::ForMapInstanceType() {
 // static
 FieldAccess AccessBuilder::ForStringLength(Zone* zone) {
   return {kTaggedBase, String::kLengthOffset, Handle<Name>(),
-          Type::Range(0, String::kMaxLength, zone), kMachAnyTagged};
+          Type::Intersect(Type::Range(0, String::kMaxLength, zone),
+                          Type::TaggedSigned(), zone),
+          kMachAnyTagged};
 }