8385746: S390: Improve receiver type profiling reliability

[offamitkumar]

s390 port, other architectures have already been ported.

Testing:

• s390x-linux-fastdebug : tier1 + hotspot_compiler

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Progress

• Change must not contain extraneous whitespace
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• Change must be properly reviewed (2 reviews required, with at least 1 Reviewer, 1 Author)

Issue

• JDK-8385746: S390: Improve receiver type profiling reliability (Enhancement - P4)

Reviewers

• Aleksey Shipilev (@shipilev - Reviewer) 🔄 Re-review required (review applies to 2aca63b3)
• Martin Doerr (@TheRealMDoerr - Reviewer)

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/jdk.git pull/31510/head:pull/31510
$ git checkout pull/31510

Update a local copy of the PR:
$ git checkout pull/31510
$ git pull https://git.openjdk.org/jdk.git pull/31510/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 31510

View PR using the GUI difftool:
$ git pr show -t 31510

Using diff file

Download this PR as a diff file:
https://git.openjdk.org/jdk/pull/31510.diff

Using Webrev

Link to Webrev Comment

[bridgekeeper]

👋 Welcome back amitkumar! A progress list of the required criteria for merging this PR into master will be added to the body of your pull request. There are additional pull request commands available for use with this pull request.

[openjdk]

@offamitkumar This change is no longer ready for integration - check the PR body for details.

[openjdk]

@offamitkumar The following label will be automatically applied to this pull request:

• hotspot

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[openjdk]

The total number of required reviews for this PR has been set to 2 based on the presence of this label: hotspot. This can be overridden with the /reviewers command.

[mlbridge]

Webrevs

• 01: Full - Incremental (ee856778)
• 00: Full (2aca63b3)

[shipilev]

Looks like a reasonable port of the original change.

[offamitkumar]

@TheRealMDoerr can you take a look at this, as it is derived from ppc changes.

[TheRealMDoerr]

Note that s390 also has instructions for counted loops which would probably generate shorter code. Nevertheless, looks correct.