Re: RFR: 8330595: Invoke ObjectMethods::bootstrap method exactly [v3]
On Fri, 19 Apr 2024 07:42:19 GMT, Claes Redestad wrote: >> Investigating a recent regression in mainline I realized we have an >> opportunity to improve the bootstrap overheads of ObjectMethods::bootstrap >> by using `invokeExact` in a way similar to what we already do for LMF and >> SCF BSMs. This avoids generating type checking adapters and equates to a >> one-off startup win of around 5ms in any app that ever has the need to spin >> up a toString, equals or hashCode method on a record. > > Claes Redestad has updated the pull request incrementally with two additional > commits since the last revision: > > - Copyright > - Formatting Thanks for the reviews, Mandy! - PR Comment: https://git.openjdk.org/jdk/pull/18845#issuecomment-2068853277
Re: RFR: 8330595: Invoke ObjectMethods::bootstrap method exactly [v3]
On Fri, 19 Apr 2024 07:42:19 GMT, Claes Redestad wrote: >> Investigating a recent regression in mainline I realized we have an >> opportunity to improve the bootstrap overheads of ObjectMethods::bootstrap >> by using `invokeExact` in a way similar to what we already do for LMF and >> SCF BSMs. This avoids generating type checking adapters and equates to a >> one-off startup win of around 5ms in any app that ever has the need to spin >> up a toString, equals or hashCode method on a record. > > Claes Redestad has updated the pull request incrementally with two additional > commits since the last revision: > > - Copyright > - Formatting LGTM - Marked as reviewed by mchung (Reviewer). PR Review: https://git.openjdk.org/jdk/pull/18845#pullrequestreview-2011967709
Re: RFR: 8330595: Invoke ObjectMethods::bootstrap method exactly [v3]
> Investigating a recent regression in mainline I realized we have an > opportunity to improve the bootstrap overheads of ObjectMethods::bootstrap by > using `invokeExact` in a way similar to what we already do for LMF and SCF > BSMs. This avoids generating type checking adapters and equates to a one-off > startup win of around 5ms in any app that ever has the need to spin up a > toString, equals or hashCode method on a record. Claes Redestad has updated the pull request incrementally with two additional commits since the last revision: - Copyright - Formatting - Changes: - all: https://git.openjdk.org/jdk/pull/18845/files - new: https://git.openjdk.org/jdk/pull/18845/files/86ccbbba..b67ee397 Webrevs: - full: https://webrevs.openjdk.org/?repo=jdk&pr=18845&range=02 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=18845&range=01-02 Stats: 3 lines in 1 file changed: 0 ins; 0 del; 3 mod Patch: https://git.openjdk.org/jdk/pull/18845.diff Fetch: git fetch https://git.openjdk.org/jdk.git pull/18845/head:pull/18845 PR: https://git.openjdk.org/jdk/pull/18845
Re: RFR: 8330595: Invoke ObjectMethods::bootstrap method exactly [v2]
On Fri, 19 Apr 2024 04:45:56 GMT, Chen Liang wrote:
>> Claes Redestad has updated the pull request incrementally with one
>> additional commit since the last revision:
>>
>> Use Arrays.copyOfRange
>
> src/java.base/share/classes/java/lang/invoke/BootstrapMethodInvoker.java line
> 150:
>
>> 148: } else if (isObjectMethodsBootstrapBSM(bsmType)) {
>> 149: MethodHandle[] methodHandles = new
>> MethodHandle[argv.length - 2];
>> 150: System.arraycopy(argv, 2, methodHandles, 0,
>> argv.length - 2);
>
> Are we avoiding `Arrays.copyOfRange(argv, 2, argv.length,
> MethodHandle.class)` because of the JIT? If JIT compiler can recognize
> `MethodHandle.class` constant and inline I recommend using copyOfRange like
> for string concat above.
No, I actually reached for the appropriate `copyOfRange` method, but my IDE hid
it from view in favor of `copyOfRange(T[], int, int)` and all the others.
-
PR Review Comment: https://git.openjdk.org/jdk/pull/18845#discussion_r1571928355
Re: RFR: 8330595: Invoke ObjectMethods::bootstrap method exactly [v2]
> Investigating a recent regression in mainline I realized we have an > opportunity to improve the bootstrap overheads of ObjectMethods::bootstrap by > using `invokeExact` in a way similar to what we already do for LMF and SCF > BSMs. This avoids generating type checking adapters and equates to a one-off > startup win of around 5ms in any app that ever has the need to spin up a > toString, equals or hashCode method on a record. Claes Redestad has updated the pull request incrementally with one additional commit since the last revision: Use Arrays.copyOfRange - Changes: - all: https://git.openjdk.org/jdk/pull/18845/files - new: https://git.openjdk.org/jdk/pull/18845/files/31752237..86ccbbba Webrevs: - full: https://webrevs.openjdk.org/?repo=jdk&pr=18845&range=01 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=18845&range=00-01 Stats: 2 lines in 1 file changed: 0 ins; 1 del; 1 mod Patch: https://git.openjdk.org/jdk/pull/18845.diff Fetch: git fetch https://git.openjdk.org/jdk.git pull/18845/head:pull/18845 PR: https://git.openjdk.org/jdk/pull/18845
Re: RFR: 8330595: Invoke ObjectMethods::bootstrap method exactly
On Thu, 18 Apr 2024 20:11:15 GMT, Claes Redestad wrote:
> Investigating a recent regression in mainline I realized we have an
> opportunity to improve the bootstrap overheads of ObjectMethods::bootstrap by
> using `invokeExact` in a way similar to what we already do for LMF and SCF
> BSMs. This avoids generating type checking adapters and equates to a one-off
> startup win of around 5ms in any app that ever has the need to spin up a
> toString, equals or hashCode method on a record.
src/java.base/share/classes/java/lang/invoke/BootstrapMethodInvoker.java line
150:
> 148: } else if (isObjectMethodsBootstrapBSM(bsmType)) {
> 149: MethodHandle[] methodHandles = new
> MethodHandle[argv.length - 2];
> 150: System.arraycopy(argv, 2, methodHandles, 0,
> argv.length - 2);
Are we avoiding `Arrays.copyOfRange(argv, 2, argv.length, MethodHandle.class)`
because of the JIT? If JIT compiler can recognize `MethodHandle.class` constant
and inline I recommend using copyOfRange like for string concat above.
-
PR Review Comment: https://git.openjdk.org/jdk/pull/18845#discussion_r1571783566
RFR: 8330595: Invoke ObjectMethods::bootstrap method exactly
Investigating a recent regression in mainline I realized we have an opportunity to improve the bootstrap overheads of ObjectMethods::bootstrap by using `invokeExact` in a way similar to what we already do for LMF and SCF BSMs. This avoids generating type checking adapters and equates to a one-off startup win of around 5ms in any app that ever has the need to spin up a toString, equals or hashCode method on a record. - Commit messages: - 8330595: Invoke ObjectMethods::bootstrap method exactly Changes: https://git.openjdk.org/jdk/pull/18845/files Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=18845&range=00 Issue: https://bugs.openjdk.org/browse/JDK-8330595 Stats: 17 lines in 1 file changed: 16 ins; 1 del; 0 mod Patch: https://git.openjdk.org/jdk/pull/18845.diff Fetch: git fetch https://git.openjdk.org/jdk.git pull/18845/head:pull/18845 PR: https://git.openjdk.org/jdk/pull/18845
