On Fri, 17 Mar 2023 13:51:05 GMT, Frederic Parain <fpar...@openjdk.org> wrote:
>> Please review this change re-implementing the FieldInfo data structure. >> >> The FieldInfo array is an old data structure storing fields metadata. It has >> poor extension capabilities, a complex management code because of lack of >> strong typing and semantic overloading, and a poor memory efficiency. >> >> The new implementation uses a compressed stream to store those metadata, >> achieving better memory density and providing flexible extensibility, while >> exposing a strongly typed set of data when uncompressed. The stream is >> compressed using the unsigned5 encoding, which alreay present in the JDK >> (because of pack200) and the JVM (because JIT compulers use it to comrpess >> debugging information). >> >> More technical details are available in the CR: >> https://bugs.openjdk.org/browse/JDK-8292818 >> >> Those changes include a re-organisation of fields' flags, splitting the >> previous heterogeneous AccessFlags field into three distincts flag >> categories: immutable flags from the class file, immutable fields defined by >> the JVM, and finally mutable flags defined by the JVM. >> >> The SA, CI, and JVMCI, which all used to access the old FieldInfo array, >> have been updated too to deal with the new FieldInfo format. >> >> Tested with mach5, tier 1 to 7. >> >> Thank you. > > Frederic Parain has updated the pull request incrementally with one > additional commit since the last revision: > > Style fixes src/jdk.hotspot.agent/share/classes/sun/jvm/hotspot/oops/InstanceKlass.java line 268: > 266: > 267: Field getField(int index) { > 268: synchronized(this) { nit Suggestion: synchronized (this) { src/jdk.hotspot.agent/share/classes/sun/jvm/hotspot/tools/jcore/ClassWriter.java line 380: > 378: dos.writeShort(accessFlags & (short) > JVM_RECOGNIZED_FIELD_MODIFIERS); > 379: > 380: int nameIndex = klass.getFieldNameIndex(index); nit: Suggestion: int nameIndex = klass.getFieldNameIndex(index); ------------- PR: https://git.openjdk.org/jdk/pull/12855
