On Tue, 19 Nov 2024 16:18:48 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. The as_int() was because we are using the AccessFlags as an _integral_ value. I was trying to minimize the effects of the change and the code uses AccessFlags as an integral value. as_int() returns u2 so I guess that's confusing. I don't want AccessFlags::get_flags() because that's implies the return is AccessFlags. I could change the name to as_unsigned_short(). Would that be less confusing? Thank you David for looking through this change. ------------- PR Comment: https://git.openjdk.org/jdk/pull/22246#issuecomment-2553766012
