8329433: Reduce nmethod header size

[vnkozlov]

This is part of changes which try to reduce size of nmethod and codeblob data vs code in CodeCache.
These changes reduced size of nmethod header from 288 to 232 bytes. From 304 to 248 in optimized VM:

Statistics for 1282 bytecoded nmethods for C2:
 total in heap = 5560352 (100%)
 header = 389728 (7.009053%)

vs

Statistics for 1322 bytecoded nmethods for C2:
 total in heap  = 8307120 (100%)
 header         = 327856 (3.946687%)

Several unneeded fields in nmethod and CodeBlob were removed. Some fields were changed from int to int16_t with added corresponding asserts to make sure their values are fit into 16 bits.

I did additional cleanup after recent CompiledMethod removal.

Tested tier1-7,stress,xcomp and performance testing.

---

Progress

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Issue

• JDK-8329433: Reduce nmethod header size (Enhancement - P4)

Reviewers

• Dean Long (@dean-long - Reviewer)
• Igor Veresov (@veresov - Reviewer)

Reviewing

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Checkout this PR locally:
$ git fetch https://git.openjdk.org/jdk.git pull/18768/head:pull/18768
$ git checkout pull/18768

Update a local copy of the PR:
$ git checkout pull/18768
$ git pull https://git.openjdk.org/jdk.git pull/18768/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 18768

View PR using the GUI difftool:
$ git pr show -t 18768

Using diff file

Download this PR as a diff file:
https://git.openjdk.org/jdk/pull/18768.diff

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[bridgekeeper]

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[openjdk]

@vnkozlov This change now passes all automated pre-integration checks.

ℹ️ This project also has non-automated pre-integration requirements. Please see the file CONTRIBUTING.md for details.

After integration, the commit message for the final commit will be:

8329433: Reduce nmethod header size

Reviewed-by: dlong, iveresov

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At the time when this comment was updated there had been 24 new commits pushed to the master branch:

• 3c1d1d9: 8320522: Remove code related to RegisterFinalizersAtInit
• 650ca65: 8329330: NoClassDefFoundError: Could not initialize class jdk.jfr.internal.MirrorEvents
• 177092b: 8330569: Rename Nix to Posix in platform-dependent attachListener code
• eb60822: 8310072: JComboBox/DisabledComboBoxFontTestAuto: Enabled and disabled ComboBox does not match in these LAFs: GTK+
• 85261bc: 8330266: RISC-V: Restore frm to RoundingMode::rne after JNI
• 9f2a4fa: 8330572: jdk.internal.net.http.HttpConnection calls an expensive checkOpen() when returning a HTTP/1.1 connection to the pool
• 8990864: 8330156: RISC-V: Range check auipc + signed 12 imm instruction
• 46a2ce4: 8330063: Upgrade jQuery to 3.7.1
• 252c62a: 8330524: Linux ppc64le compile warning with clang in os_linux_ppc.cpp
• 32946e1: 8295111: dpkg appears to have problems resolving symbolically linked native libraries
• ... and 14 more: https://git.openjdk.org/jdk/compare/064628471b83616b4463baa78618d1b7a66d0c7c...master

As there are no conflicts, your changes will automatically be rebased on top of these commits when integrating. If you prefer to avoid this automatic rebasing, please check the documentation for the /integrate command for further details.

➡️ To integrate this PR with the above commit message to the master branch, type /integrate in a new comment.

[openjdk]

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[mlbridge]

Webrevs

• 07: Full - Incremental (5f5f30de)
• 06: Full (adc17594)
• 05: Full - Incremental (6a164b11)
• 04: Full - Incremental (8405a23d)
• 03: Full - Incremental (6cb22e81)
• 02: Full - Incremental (13744e78)
• 01: Full - Incremental (488f1b92)
• 00: Full (a0c46b86)

[vnkozlov]

@dean-long, thank you for review. I applied all your suggestions and push it after testing.

[vnkozlov]

Merge #18637 added an other short field _num_stack_arg_slots which pushed nmethod size back to 240 bytes in product VM. I will not do changes in this PR to compensate it.

[vnkozlov]

I remove ASSERT blocks to address the last @dean-long comment.

[vnkozlov]

Waiting second review.

[veresov]

Looks good.

[vnkozlov]

Thank you @dean-long, @coleenp, @JohnTortugo and @veresov for reviews.

[vnkozlov]

/integrate

[openjdk]

Going to push as commit b704e91.
Since your change was applied there have been 25 commits pushed to the master branch:

• 8da175d: 8330008: [s390x] Test bit "in-memory" in case of DiagnoseSyncOnValueBasedClasses
• 3c1d1d9: 8320522: Remove code related to RegisterFinalizersAtInit
• 650ca65: 8329330: NoClassDefFoundError: Could not initialize class jdk.jfr.internal.MirrorEvents
• 177092b: 8330569: Rename Nix to Posix in platform-dependent attachListener code
• eb60822: 8310072: JComboBox/DisabledComboBoxFontTestAuto: Enabled and disabled ComboBox does not match in these LAFs: GTK+
• 85261bc: 8330266: RISC-V: Restore frm to RoundingMode::rne after JNI
• 9f2a4fa: 8330572: jdk.internal.net.http.HttpConnection calls an expensive checkOpen() when returning a HTTP/1.1 connection to the pool
• 8990864: 8330156: RISC-V: Range check auipc + signed 12 imm instruction
• 46a2ce4: 8330063: Upgrade jQuery to 3.7.1
• 252c62a: 8330524: Linux ppc64le compile warning with clang in os_linux_ppc.cpp
• ... and 15 more: https://git.openjdk.org/jdk/compare/064628471b83616b4463baa78618d1b7a66d0c7c...master

Your commit was automatically rebased without conflicts.

[openjdk]

@vnkozlov Pushed as commit b704e91.

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