On Wed, 10 Jun 2026 07:15:58 GMT, David Simms <[email protected]> wrote:
>> This is a "*sub-review pull request*" for the first >> [preview](https://openjdk.org/jeps/12) of [JEP 401: Value Classes and >> Objects](https://openjdk.org/jeps/401), specifically >> [JDK-8317278](https://bugs.openjdk.org/browse/JDK-8317278): JVM >> implementation of value classes and objects. >> >>> [!NOTE] >>> This pull request and the other sub-review pull requests listed below are >>> based on the "*master pull request*" >>> (https://github.com/openjdk/jdk/pull/31120). It contains the same full set >>> of code changes as the "*master pull request*" to preserve the full >>> implementation context; the language compiler, JVM, and standard library >>> changes are intertwined. This separate pull requests exist only to >>> subdivide the review and related discussion by area. >> >> Other areas for review: >> >> - [JDK-8317277](https://bugs.openjdk.org/browse/JDK-8317277): Java language >> implementation of value classes and objects >> - https://github.com/openjdk/jdk/pull/31121 >> - [JDK-8317279](https://bugs.openjdk.org/browse/JDK-8317279): Standard >> library implementation of value classes and objects >> - https://github.com/openjdk/jdk/pull/31123 >> >> Code changes resulting from the review process should be made in >> [`valhalla/lworld`](https://github.com/openjdk/valhalla/). >> >> `valhalla/lworld` is currently updated from `jdk/master` whenever a weekly >> [`jdk` tag](https://github.com/openjdk/jdk/tags) is created. At that time, >> code changes from `valhalla/lworld` will be propagated to the master pull >> request and to all sub-review pull requests, including this one. >> >> Ultimately, review sign-off will be recorded on the "*master pull request*", >> and this pull request will be closed without integration. >> >> This pull request has a large code surface area and often conflicts with >> `jdk/master` on a daily basis. Refer to >> [`valhalla/lworld`](https://github.com/openjdk/valhalla/) for the latest >> state of the project code, keeping in mind that it may lag several days >> behind `jdk/master`. Both repositories may be needed as references during >> review. >> >> --------- >> - [x] I confirm that I make this contribution in accordance with the >> [OpenJDK Interim AI Policy](https://openjdk.org/legal/ai). > > David Simms has updated the pull request with a new target base due to a > merge or a rebase. The pull request now contains 2798 commits: > > - Merge remote-tracking branch 'valhalla/lworld' into > jep401_sub_review_8317278 > - 8386239: [lworld] Update jdk/java/util/Arrays/ArraysEqCmpTest.java > > Reviewed-by: liach > - 8386242: [lworld] Simplify and clarify StrictProcessor > > Reviewed-by: dsimms > - 8386140: [lworld] FieldReflector using wrong Class argument > > Reviewed-by: alanb, dsimms > - 8386216: [lworld] Rollback meaningless diff in EventClassBuilder > > Reviewed-by: dsimms > - 8385170: [lworld] Serialization spec needs to allow abstract value classes > like Number > > Reviewed-by: liach > - 8385980: [lworld] Standardize pattern for preview value class generation > > Reviewed-by: liach > - 8386086: [lworld] > sun/jvmstat/monitor/MonitoredVm/MonitorVmStartTerminate.java should be > removed from problem list > > Reviewed-by: liach, dcubed > - Merge > > Merge jdk-28+1 > - 8386090: [lworld] Redundant test changes in lworld versus mainline > > Reviewed-by: vromero > - ... and 2788 more: https://git.openjdk.org/jdk/compare/92298786...f76a5106 Minor cleanup would be nice: diff --git a/src/hotspot/cpu/aarch64/c1_LIRAssembler_aarch64.cpp b/src/hotspot/cpu/aarch64/c1_LIRAssembler_aarch64.cpp index c74ff16ae26..1fc0f43ed6c 100644 --- a/src/hotspot/cpu/aarch64/c1_LIRAssembler_aarch64.cpp +++ b/src/hotspot/cpu/aarch64/c1_LIRAssembler_aarch64.cpp @@ -1640,15 +1640,13 @@ void LIR_Assembler::emit_opSubstitutabilityCheck(LIR_OpSubstitutabilityCheck* op move(op->not_equal_result(), op->result_opr()); __ b(L_end); - __ bind(L_oops_equal); - move(op->equal_result(), op->result_opr()); - __ b(L_end); - // We've returned from the stub. R0 contains 0x0 IFF the two // operands are not substitutable. (Don't compare against 0x1 in case the // C compiler is naughty) __ bind(*op->stub()->continuation()); __ cbz(r0, L_oops_not_equal); // (call_stub() == 0x0) -> not_equal + + __ bind(L_oops_equal); move(op->equal_result(), op->result_opr()); // (call_stub() != 0x0) -> equal // fall-through __ bind(L_end); diff --git a/src/hotspot/cpu/x86/c1_LIRAssembler_x86.cpp b/src/hotspot/cpu/x86/c1_LIRAssembler_x86.cpp index 01f4a8c1fb7..0b219f53817 100644 --- a/src/hotspot/cpu/x86/c1_LIRAssembler_x86.cpp +++ b/src/hotspot/cpu/x86/c1_LIRAssembler_x86.cpp @@ -1639,16 +1639,14 @@ void LIR_Assembler::emit_opSubstitutabilityCheck(LIR_OpSubstitutabilityCheck* op move(op->not_equal_result(), op->result_opr()); __ jmp(L_end); - __ bind(L_oops_equal); - move(op->equal_result(), op->result_opr()); - __ jmp(L_end); - // We've returned from the stub. RAX contains 0x0 IFF the two // operands are not substitutable. (Don't compare against 0x1 in case the // C compiler is naughty) __ bind(*op->stub()->continuation()); __ cmpl(rax, 0); __ jcc(Assembler::equal, L_oops_not_equal); // (call_stub() == 0x0) -> not_equal + + __ bind(L_oops_equal); move(op->equal_result(), op->result_opr()); // (call_stub() != 0x0) -> equal // fall-through __ bind(L_end); ------------- PR Comment: https://git.openjdk.org/jdk/pull/31122#issuecomment-4684643821
