Issue #10333 has been updated by Eric Wong. ko1 / atdot.net wrote: > I can't find out which methods are target. > How to see the list? > > I'm afraid that many optimized methods becomes overhead for non-target methods. Most comments + optimization are in compile.c (still awork-in-progress). The peephole optimization phase rewrites many putstring instructions to opt_str_lit instructions (same insn length). Sorry my last (v2) patch is dirty. Still a work-in-progress. I'll try to get an updated patch out this week. For sub/gsub/tr* methods, the optimization is an obvious win: the only common use for methods with those method names is with the String class; so it is effective. I think start_with?/end_with?/squeeze/pack/unpack fall into the same category: common case is only one core class uses them with string literals. This makes opt_str_lit a win with those method names. For some method names (include?/delete/key?); I see them often used with both core (Array/Hash) and non-core (Set/GDBM) classes. We need to be careful with common method names and string literal. Maybe we may use dynamic instruction rewriting if we detect uses on non-core classes and dynamically rewrite opt_str_lit back to putstring. Note: opt_str_lit has the same insn length as putstring; we may rewrite iseq->iseq at runtime. ---------------------------------------- Feature #10333: [PATCH 3/1] optimize: "yoda literal" == string https://bugs.ruby-lang.org/issues/10333#change-49489 * Author: Eric Wong * Status: Open * Priority: Normal * Assignee: * Category: core * Target version: current: 2.2.0 ---------------------------------------- This is a follow-up-to: 1) [Feature #10326] optimize: recv << "literal string" 2) [Feature #10329] optimize: foo == "literal string" This can be slightly faster than: (string == "literal") because we can guaranteed the "yoda literal" is already a string at compile time. Updated benchmarks from Xeon E3-1230 v3 @ 3.30GHz: target 0: trunk (ruby 2.2.0dev (2014-10-06 trunk 47822) [x86_64-linux]) at "/home/ew/rrrr/b/i/bin/ruby" target 1: built (ruby 2.2.0dev (2014-10-06 trunk 47822) [x86_64-linux]) at "/home/ew/ruby/b/i/bin/ruby" ----------------------------------------------------------- loop_whileloop2 ~~~ruby i = 0 while i< 6_000_000 # benchmark loop 2 i += 1 end ~~~ ~~~ trunk 0.10712811909615993 trunk 0.10693809622898698 trunk 0.10645449301227927 trunk 0.10646287119016051 built 0.10612367931753397 built 0.10581812914460897 built 0.10592922195792198 built 0.10595094738528132 ~~~ ----------------------------------------------------------- vm2_streq1 ~~~ruby i = 0 foo = "literal" while i<6_000_000 # benchmark loop 2 i += 1 foo == "literal" end ~~~ ~~~ trunk 0.47250875690951943 trunk 0.47325073881074786 trunk 0.4726782930083573 trunk 0.4727754699997604 built 0.185972370672971 built 0.1850820742547512 built 0.18558283289894462 built 0.18452610215172172 ~~~ ----------------------------------------------------------- vm2_streq2 ~~~ruby i = 0 foo = "literal" while i<6_000_000 # benchmark loop 2 i += 1 "literal" == foo end ~~~ ~~~ trunk 0.4719057851471007 trunk 0.4715963830240071 trunk 0.47177061904221773 trunk 0.4724834677763283 built 0.18247668212279677 built 0.18143231887370348 built 0.18060296680778265 built 0.17929687118157744 ~~~ ----------------------------------------------------------- raw data: ~~~ [["loop_whileloop2", [[0.10712811909615993, 0.10693809622898698, 0.10645449301227927, 0.10646287119016051], [0.10612367931753397, 0.10581812914460897, 0.10592922195792198, 0.10595094738528132]]], ["vm2_streq1", [[0.47250875690951943, 0.47325073881074786, 0.4726782930083573, 0.4727754699997604], [0.185972370672971, 0.1850820742547512, 0.18558283289894462, 0.18452610215172172]]], ["vm2_streq2", [[0.4719057851471007, 0.4715963830240071, 0.47177061904221773, 0.4724834677763283], [0.18247668212279677, 0.18143231887370348, 0.18060296680778265, 0.17929687118157744]]]] Elapsed time: 6.097474559 (sec) ~~~ ----------------------------------------------------------- benchmark results: minimum results in each 4 measurements. Execution time (sec) name |trunk |built --------+-------+------- loop_whileloop2 |0.106 |0.106 vm2_streq1* |0.366 |0.079 vm2_streq2* |0.365 |0.073 Speedup ratio: compare with the result of `trunk' (greater is better) name |built --------+------- loop_whileloop2 |1.006 vm2_streq1* |4.651 vm2_streq2* |4.969 --- ~~~ benchmark/bm_vm2_streq2.rb | 6 ++++++ compile.c | 20 +++++++++++++++++++- insns.def | 20 ++++++++++++++++++++ test/ruby/test_string.rb | 12 ++++++++---- 4 files changed, 53 insertions(+), 5 deletions(-) create mode 100644 benchmark/bm_vm2_streq2.rb ~~~ ---Files-------------------------------- 0001-optimize-yoda-literal-string.patch (6.23 KB) -- https://bugs.ruby-lang.org/