On Sun, 21 Jul 2024 12:25:36 GMT, Shaojin Wen <d...@openjdk.org> wrote:
> The current strategy for bootstrapping JEP 280 String concat expressions uses > either an optimized MH expression tree, or, due to scalability issues with > that implementation, a per call-site StringBuilder-based class generation > scheme. > > This RFE seeks to unify these into a single strategy that uses per-shape > class generation emitting code semantically similar to the optimized MH > expression tree. Using hidden classes installed into java.lang with access to > the StringConcatHelper set of utility methods this can achieve similar > throughput performance, while reducing the number of generated classes at > high arities, reducing startup overheads, and improving warmup > characteristics. > > This RFE was initially prompted by a suggestion of @cl4es in the discussion > of PR #20253 > (https://github.com/openjdk/jdk/pull/20253#issuecomment-2240412866), and then > evolved after collaborating on this issue into this full re-implementation. This pull request has now been integrated. Changeset: 5022109b Author: Shaojin Wen <shaojin.we...@alibaba-inc.com> Committer: Claes Redestad <redes...@openjdk.org> URL: https://git.openjdk.org/jdk/commit/5022109b2a33a8cf2608eb829098b27641b731a4 Stats: 1345 lines in 8 files changed: 1212 ins; 29 del; 104 mod 8336856: Efficient hidden class-based string concatenation strategy Co-authored-by: Claes Redestad <redes...@openjdk.org> Reviewed-by: redestad, liach ------------- PR: https://git.openjdk.org/jdk/pull/20273
