On Thu, 19 Dec 2024 22:22:13 GMT, Coleen Phillimore <cole...@openjdk.org> wrote:
>> Please review this change that makes AccessFlags and modifier_flags u2 types >> and removes the last remnants of Hotspot adding internal access flags. This >> change moves AccessFlags and modifier_flags in Klass to alignment gaps >> saving 16 bytes. From pahole: so it's a bit better. >> >> before: >> >> /* size: 216, cachelines: 4, members: 25, static members: 17 */ >> /* sum members: 194, holes: 3, sum holes: 18 */ >> >> >> after: >> >> /* size: 200, cachelines: 4, members: 25, static members: 17 */ >> /* sum members: 188, holes: 4, sum holes: 12 */ >> >> >> We may eventually move the modifiers to java.lang.Class but that's WIP. >> >> Tested with tier1-7 on oracle platforms. Did test builds on other platforms >> (please try these changes ppc/arm32 and s390). Also requires minor Graal >> changes. > > Coleen Phillimore has updated the pull request incrementally with one > additional commit since the last revision: > > Use ldrh rather than load_unsigned_short for aarch64, use testbitdi for ppc. Things become somewhat clearer once one realizes/recalls that `AccessFlags` do not specifically pertain to access, but to all class/method modifiers as per the various JVMS ACC_XXX constants. We need to restore the leading comment in accessFlags.hpp to read // AccessFlags is an abstraction over Java ACC flags. as it originally did. ------------- PR Comment: https://git.openjdk.org/jdk/pull/22246#issuecomment-2556293078
