> 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 ------------- Changes: https://git.openjdk.java.net/jdk/pull/5027/files Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=5027&range=14 Stats: 6409 lines in 78 files changed: 5864 ins; 317 del; 228 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
