RFR: 8357793: [PPC64] VM crashes with -XX:-UseSIGTRAP -XX:-ImplicitNullChecks [v2]

[Martin Doerr]

> In case of -XX:-UseSIGTRAP -XX:-ImplicitNullChecks, we use the manually selected entry. (The same is true for -XX:-TrapBasedNullChecks -XX:-ImplicitNullChecks.)
> We only need to use the correct NullPointerException entry in the compiler case.
> 
> With this patch, the manually selected entry matches the one selected by `PosixSignals::pd_hotspot_signal_handler`.

Martin Doerr has updated the pull request incrementally with one additional commit since the last revision:

  Fix bastore without ImplicitNullChecks.

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/25504/files
  - new: https://git.openjdk.org/jdk/pull/25504/files/fe0a8a16..bf0d04a4

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=25504&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=25504&range=00-01

  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/25504.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/25504/head:pull/25504

PR: https://git.openjdk.org/jdk/pull/25504