On Tue, 26 Oct 2021 16:35:34 GMT, Mandy Chung <mch...@openjdk.org> wrote:
>> This reimplements core reflection with method handles. >> >> For `Constructor::newInstance` and `Method::invoke`, the new implementation >> uses `MethodHandle`. For `Field` accessor, the new implementation uses >> `VarHandle`. For the first few invocations of one of these reflective >> methods on a specific reflective object we invoke the corresponding method >> handle directly. After that we spin a dynamic bytecode stub defined in a >> hidden class which loads the target `MethodHandle` or `VarHandle` from its >> class data as a dynamically computed constant. Loading the method handle >> from a constant allows JIT to inline the method-handle invocation in order >> to achieve good performance. >> >> The VM's native reflection methods are needed during early startup, before >> the method-handle mechanism is initialized. That happens soon after >> System::initPhase1 and before System::initPhase2, after which we switch to >> using method handles exclusively. >> >> The core reflection and method handle implementation are updated to handle >> chained caller-sensitive method calls [1] properly. A caller-sensitive >> method can define with a caller-sensitive adapter method that will take an >> additional caller class parameter and the adapter method will be annotated >> with `@CallerSensitiveAdapter` for better auditing. See the detailed >> description from [2]. >> >> Ran tier1-tier8 tests. >> >> [1] https://bugs.openjdk.java.net/browse/JDK-8013527 >> [2] >> https://bugs.openjdk.java.net/browse/JDK-8271820?focusedCommentId=14439430&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-14439430 > > Mandy Chung has updated the pull request with a new target base due to a > merge or a rebase. The pull request now contains 40 commits: > > - Fall back to the VM native reflection support if method handle cannot be > created > - fix bug id in test > - Merge > - Merge branch 'master' of https://github.com/openjdk/jdk into > reimplement-method-invoke > - Merge branch 'master' of https://github.com/openjdk/jdk into > reimplement-method-invoke > - Separate paramFlgas into paramCount and flags fields > - Minor cleanup. Improve javadoc in CallerSensitiveAdapter > - Fix left-over assignment > - Remove duplicated microbenchmarks > - Avoid pitfall with unwanted inlining in some cases. Also remove > boxing/unboxing to focus on the invocation cost > - ... and 30 more: > https://git.openjdk.java.net/jdk/compare/97d3280e...64738bb2 src/java.base/share/classes/jdk/internal/reflect/AccessorUtils.java line 34: > 32: */ > 33: public class AccessorUtils { > 34: static boolean isIllegalArgument(Class<?> accessorType, > RuntimeException e) { It might be useful to add a method description. In isolation, it's not immediately clear what it does. ------------- PR: https://git.openjdk.java.net/jdk/pull/5027
