8354887: Preserve runtime blobs in AOT code cache #25019

ashu-mehra · 2025-05-03T04:10:01Z

8350209 introduced the framework for storing code in aot code cache and used it for caching i2c/c2i adapters.
This PR extends the AOTCodeCache infrastructure and stores various runtime blobs (shared blobs, C1 and C2 runtime blobs) in the AOT code cache. It adds a new diagnostic flag AOTStubCaching to enable/disable the caching of these blobs.
AOTCodeFlags.java test is extended to cover AOTStubCaching.

Progress

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Issue

JDK-8354887: Preserve runtime blobs in AOT code cache (Enhancement - P4)

Reviewers

Vladimir Kozlov (@vnkozlov - Reviewer)
Andrew Dinn (@adinn - Reviewer)

Contributors

Andrew Dinn <adinn@openjdk.org>

Reviewing

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$ git checkout pull/25019

Update a local copy of the PR:
$ git checkout pull/25019
$ git pull https://git.openjdk.org/jdk.git pull/25019/head

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$ git pr checkout 25019

View PR using the GUI difftool:
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https://git.openjdk.org/jdk/pull/25019.diff

Using Webrev

Link to Webrev Comment

Signed-off-by: Ashutosh Mehra <asmehra@redhat.com>

Ensure CompressedOops::base and CompressedKlssPointers::base does not change in production run Signed-off-by: Ashutosh Mehra <asmehra@redhat.com>

Signed-off-by: Ashutosh Mehra <asmehra@redhat.com>

bridgekeeper · 2025-05-03T04:10:42Z

👋 Welcome back asmehra! 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 · 2025-05-03T04:11:28Z

@ashu-mehra 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:

8354887: Preserve runtime blobs in AOT code cache

Co-authored-by: Andrew Dinn <adinn@openjdk.org>
Reviewed-by: kvn, adinn

You can use pull request commands such as /summary, /contributor and /issue to adjust it as needed.

At the time when this comment was updated there had been 51 new commits pushed to the master branch:

850c789: 8349754: Invalid "early reference" error when class extends an outer class
1e61352: 8356709: Avoid redundant String formatting in BigDecimal.valueOf(double)
e056bbe: 8356822: Refactor HTML anchor tags to javadoc in Charset
... and 48 more: https://git.openjdk.org/jdk/compare/d1543429ff29ca0d761b8473b3fb8621abcd226d...master

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openjdk · 2025-05-03T04:11:56Z

@ashu-mehra The following label will be automatically applied to this pull request:

hotspot

When this pull request is ready to be reviewed, an "RFR" email will be sent to the corresponding mailing list. If you would like to change these labels, use the /label pull request command.

ashu-mehra · 2025-05-03T04:16:04Z

/cc hotspot-runtime
/cc hotspot-compiler

/label remove hotspot

openjdk · 2025-05-03T04:17:02Z

@ashu-mehra
The hotspot-runtime label was successfully added.

openjdk · 2025-05-03T04:17:29Z

@ashu-mehra
The hotspot-compiler label was successfully added.

openjdk · 2025-05-03T04:17:51Z

@ashu-mehra
The hotspot label was successfully removed.

mlbridge · 2025-05-03T04:21:30Z

Webrevs

vnkozlov

Few comments.

vnkozlov · 2025-05-03T16:44:52Z

src/hotspot/cpu/x86/x86_64.ad

+    if (AOTCodeCache::is_on_for_dump()) {
+      // Created runtime_call_type relocation when caching code
+      __ lea(r10, RuntimeAddress((address)$meth$$method));
+    } else {
+      __ mov64(r10, (int64_t) $meth$$method);
+    }


I think we should do it always, not conditionally. On AArch64 it is unconditional - relocation processing know how to do that.

I will update premain code too later.

vnkozlov · 2025-05-03T16:48:16Z

src/hotspot/share/asm/codeBuffer.hpp

+ ~CHeapString() {
+    os::free((void*)_string);
+    _string = nullptr;
+  }


Move it into .cpp so you don't need to include os.hpp here.

Constructor too.

vnkozlov · 2025-05-03T16:52:32Z

src/hotspot/share/opto/runtime.cpp

@@ -157,6 +158,7 @@ static bool check_compiled_frame(JavaThread* thread) {
                  C2_STUB_TYPEFUNC(name),                             \
                  C2_STUB_C_FUNC(name),                               \
                  C2_STUB_NAME(name),                                 \
+                  (int)C2_STUB_ID(name),                                   \


Please, align \

vnkozlov · 2025-05-03T16:52:47Z

src/hotspot/share/opto/runtime.cpp

@@ -170,6 +172,7 @@ static bool check_compiled_frame(JavaThread* thread) {
                  notify_jvmti_vthread_Type,                            \
                  C2_JVMTI_STUB_C_FUNC(name),                         \
                  C2_STUB_NAME(name),                                 \
+                  (int)C2_STUB_ID(name),                                     \


vnkozlov · 2025-05-03T17:11:18Z