RFR: 8265327: Remove check_safepoint_and_suspend_for_native_trans() [v2]

[Patricio Chilano Mateo]

> Hi,
> 
> Please review this small fix. Method check_safepoint_and_suspend_for_native_trans() can just be removed and the code moved directly to check_special_condition_for_native_trans(). The other caller, transition_from_native(), can also just call SafepointMechanism::process_if_requested_with_exit_check() after transitioning to _thread_in_native_trans. Since that removes the only caller of is_suspend_after_native() I also removed it. 
> I also made a small fix to has_special_runtime_exit_condition(). The compilers were generating three different comparisons for _suspend_flags instead of combining the constant values and doing a single one (I checked this with gcc 10.2 on linux and clang-12 on macos). The extra code was preventing inlining on some cases. For instance, on a Linux release build with gcc 10.2, for the ThreadInVMfromNative constructor, transition_from_native() was being inlined but not process_if_requested_with_exit_check(), so we still required a call for the fast case. The small change to has_special_runtime_exit_condition() fixed that. 
> Tested in mach5 tiers1-2.
> 
> Thanks,
> 
> Patricio

Patricio Chilano Mateo has updated the pull request incrementally with one additional commit since the last revision:

  fix typo in comment for check_special_condition_for_native_trans

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

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/3548/files
  - new: https://git.openjdk.java.net/jdk/pull/3548/files/a8744c07..aec3dd71

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=3548&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=3548&range=00-01

  Stats: 2 lines in 1 file changed: 0 ins; 0 del; 2 mod
  Patch: https://git.openjdk.java.net/jdk/pull/3548.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/3548/head:pull/3548

PR: https://git.openjdk.java.net/jdk/pull/3548