In the fieldDescriptor::name and signature we dereference a constantPoolHandle and pass the ConstantPool* to methods accepting a const constantPoolHandle&. This means we create new handles, which has a small but measurable overhead.

diff -r 7e79aaa59912 src/hotspot/share/runtime/fieldDescriptor.inline.hpp
--- a/src/hotspot/share/runtime/fieldDescriptor.inline.hpp Sat Nov 02 01:03:32 2019 +0100
+++ b/src/hotspot/share/runtime/fieldDescriptor.inline.hpp Sun Nov 03 01:30:55 2019 +0100
@@ -31,11 +31,11 @@
 // must be put in this file, as they require runtime/handles.inline.hpp.

 inline Symbol* fieldDescriptor::name() const {
- return field()->name(_cp());
+ return field()->name(_cp);
 }

 inline Symbol* fieldDescriptor::signature() const {
- return field()->signature(_cp());
+ return field()->signature(_cp);
 }

 inline InstanceKlass* fieldDescriptor::field_holder() const {