RFR: 8234185: Cleanup usage of canonicalize function between libjava, hotspot and libinstrument

[Langer, Christoph]

Hi,

please review this cleanup change regarding function "canonicalize" of libjava.

Bug: https://bugs.openjdk.java.net/browse/JDK-8234185
Webrev: http://cr.openjdk.java.net/~clanger/webrevs/8234185.0/


The goal is to cleanup how this function is defined and used. One thing is, that there was an unnecessary wrapper function "Canonicalize" in jni_util.c. It wrapped the call to "canonicalize". We can get rid of this wrapper. Unfortunately, it is not possible to just export "canonicalize" since this will conflict with a method signature from the math library, at least on modern Linuxes. So I decided to call the method JDK_Canonicalize and will correctly define it in jdk_util.h which can be included everywhere.



Hotspot's classloader.cpp will dynamically resolve this method, so I add a local declaration of the function pointer in there.



This change shall be predecessor of JDK-8223261, where a review was already started here: https://mail.openjdk.java.net/pipermail/core-libs-dev/2019-November/063398.html

Thanks
Christoph