> 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 incrementally with four additional commits since the last revision: - Rename the accessor classes to make it explicit for method handles - Add a new test for testing methods whose parameter types and return type not visible to the caller - Move the handling of native accessor to the factory method for method/constructor accessor - DirectConstructorAccessorImpl should take the MHInvoker parameter ------------- Changes: - all: https://git.openjdk.java.net/jdk/pull/5027/files - new: https://git.openjdk.java.net/jdk/pull/5027/files/cff856f9..ba099fb4 Webrevs: - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=5027&range=03 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=5027&range=02-03 Stats: 658 lines in 12 files changed: 401 ins; 202 del; 55 mod Patch: https://git.openjdk.java.net/jdk/pull/5027.diff Fetch: git fetch https://git.openjdk.java.net/jdk pull/5027/head:pull/5027 PR: https://git.openjdk.java.net/jdk/pull/5027
