On Fri, 20 Dec 2024 13:17:17 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: > > Restore ACC in comment. src/hotspot/cpu/ppc/templateInterpreterGenerator_ppc.cpp line 149: > 147: // _access_flags must be a 16 bit value. > 148: assert(sizeof(AccessFlags) == 2, "wrong size"); > 149: __ lha(R11_scratch1/*access_flags*/, method_(access_flags)); Using `lhz` would be more consistent. `lha` uses sign extend instead of zero extend. Feel free to clean this up if you want. Both instructions should work. ------------- PR Review Comment: https://git.openjdk.org/jdk/pull/22246#discussion_r1897422214
