RFR: 8331731: ubsan: relocInfo.cpp:155:30: runtime error: applying non-zero offset 18446744073709551614 to null pointer [v2]

[Matthias Baesken]

> When running on macOS with ubsan enabled, we see some issues in relocInfo  (hpp and cpp); those already occur in the build quite early.
> 
> /jdk/src/hotspot/share/code/relocInfo.cpp:155:30: runtime error: applying non-zero offset 18446744073709551614 to null pointer
> 
> Similar happens when we add to the _current pointer
>     _current++;
> this gives :
> relocInfo.hpp:606:13: runtime error: applying non-zero offset to non-null pointer 0xfffffffffffffffe produced null pointer
> 
> Seems the pointer subtraction/addition worked so far, so it might be an option to disable ubsan for those 2 functions.

Matthias Baesken has updated the pull request incrementally with one additional commit since the last revision:

  use template functions

-------------

Changes:
  - all: https://git.openjdk.org/jdk/pull/19424/files
  - new: https://git.openjdk.org/jdk/pull/19424/files/ea8ecba9..bbb0c96f

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=19424&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=19424&range=00-01

  Stats: 19 lines in 2 files changed: 11 ins; 6 del; 2 mod
  Patch: https://git.openjdk.org/jdk/pull/19424.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/19424/head:pull/19424

PR: https://git.openjdk.org/jdk/pull/19424