JDK-8275201 : C2: hide klass() accessor from TypeOopPtr and typeKlassPtr subclasses
  • Type: Enhancement
  • Component: hotspot
  • Sub-Component: compiler
  • Affected Version: 18
  • Priority: P4
  • Status: Resolved
  • Resolution: Fixed
  • Submitted: 2021-10-13
  • Updated: 2022-06-24
  • Resolved: 2022-05-11
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JDK 19
19 b22Fixed
Related Reports
Relates :  
JDK-6312651 - Compiler should only use verified interface types for optimization
Relates :  
JDK-8266550 - C2: mirror TypeOopPtr/TypeInstPtr/TypeAryPtr with TypeKlassPtr/TypeInstKlassPtr/TypeAryKlassPtr
Relates :  
JDK-8289161 - Regressions 2-3% on some Renaissance after 8275201
Relates :  
JDK-8287700 - C2 Crash running eclipse benchmark from Dacapo
Relates :  
JDK-8288968 - C2: remove use of covariant returns in type.[ch]pp
Description
This is a follow up to JDK-8266550. This is refactoring in an attempt to fix JDK-6312651. This is extracted from: https://mail.openjdk.java.net/pipermail/hotspot-compiler-dev/2019-May/033803.html

The goal of this one is to prevent code outside of the Type hierarchy from using the klass() accessor as once interfaces are properly supported a single klass pointer can't exhaustively represent a type.
Comments
Changeset: aa7ccdf4 Author: Roland Westrelin <roland@openjdk.org> Date: 2022-05-11 07:25:49 +0000 URL: https://git.openjdk.java.net/jdk/commit/aa7ccdf44549a52cce9e99f6569097d3343d9ee4
11-05-2022