RFR: JDK-8294947: Use 64bit atomics in patch_verified_entry on x86_64 [v2]

[Dmitry Samersoff]

On Fri, 11 Nov 2022 22:39:32 GMT, Dean Long <dlong at openjdk.org> wrote:

>> Dmitry Samersoff has updated the pull request incrementally with one additional commit since the last revision:
>> 
>>   JDK-8294947: Use 64bit atomics in patch_verified_entry on x86_64
>
> src/hotspot/cpu/x86/nativeInst_x86.cpp line 511:
> 
>> 509: // In JVMCI, the restriction is enforced by HotSpotFrameContext.enter(...)
>> 510: //
>> 511: void NativeJump::patch_verified_entry(address entry, address verified_entry, address dest) {
> 
> Should we assert that the appropriate lock is held here?

This code can be called from different places and therefore can require different locks, so I wold prefer not to put any caller-specific logic to this function. Also, original 32bit code doesn't have such assert.

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PR: https://git.openjdk.org/jdk/pull/11059