Ruby

https://github.com/ruby/ruby/compare/trunk...nobu:feature/12403-optimize-Regexp%23match_p

benchmark results:
Execution time (sec)

Speedup ratio: compare with the result of `normal' (greater is better)

After r55102, rb_scan_args is almost statically resolved.

000000000051eae0 <rb_reg_match_m_p>: * $& #=> nil */ static VALUE rb_reg_match_m_p(int argc, VALUE *argv, VALUE re) { 51eae0: 41 57 push %r15 51eae2: 41 56 push %r14 51eae4: 41 55 push %r13 51eae6: 41 54 push %r12 51eae8: 55 push %rbp 51eae9: 89 fd mov %edi,%ebp 51eaeb: 53 push %rbx 51eaec: 48 81 ec 88 00 00 00 sub $0x88,%rsp 51eaf3: 48 8b 05 86 00 3b 00 mov 0x3b0086(%rip),%rax # 8ceb80 <_DYNAMIC+0x240> VALUE str, initpos; long pos = 0; regex_t *reg; onig_errmsg_buffer err = ""; 51eafa: 48 c7 44 24 10 00 00 movq $0x0,0x10(%rsp) 51eb01: 00 00 51eb03: 48 8d 7c 24 18 lea 0x18(%rsp),%rdi * $& #=> nil */ static VALUE rb_reg_match_m_p(int argc, VALUE *argv, VALUE re) { 51eb08: 48 8b 08 mov (%rax),%rcx 51eb0b: 48 89 4c 24 78 mov %rcx,0x78(%rsp) 51eb10: 31 c9 xor %ecx,%ecx VALUE str, initpos; long pos = 0; regex_t *reg; onig_errmsg_buffer err = ""; 51eb12: b9 0a 00 00 00 mov $0xa,%ecx 51eb17: 31 c0 xor %eax,%eax 51eb19: f3 48 ab rep stos %rax,%es:(%rdi) 51eb1c: 31 c9 xor %ecx,%ecx 51eb1e: 66 89 0f mov %cx,(%rdi) if (*p != '\0') { rb_fatal("bad scan arg format: %s", fmt); } n_mand = n_lead + n_trail; if (argc < n_mand) 51eb21: 85 ed test %ebp,%ebp 51eb23: 0f 8e 71 02 00 00 jle 51ed9a <rb_reg_match_m_p+0x2ba> 51eb29: 48 89 d3 mov %rdx,%rbx } } /* capture leading mandatory arguments */ for (i = n_lead; i-- > 0; ) { var = vars[vari++]; if (var) *var = argv[argi]; 51eb2c: 48 8b 3e mov (%rsi),%rdi argi++; } /* capture optional arguments */ for (i = n_opt; i-- > 0; ) { var = vars[vari++]; if (argi < argc - n_trail) { 51eb2f: 83 fd 01 cmp $0x1,%ebp 51eb32: 0f 84 00 01 00 00 je 51ec38 <rb_reg_match_m_p+0x158> if (var) *var = argv[argi]; 51eb38: 4c 8b 6e 08 mov 0x8(%rsi),%r13 else { *var = Qnil; } } if (argi < argc) { 51eb3c: 83 fd 02 cmp $0x2,%ebp 51eb3f: 0f 85 55 02 00 00 jne 51ed9a <rb_reg_match_m_p+0x2ba> OnigPosition result; const UChar *start, *end; int tmpreg; rb_scan_args(argc, argv, "11", &str, &initpos); if (NIL_P(str)) return Qfalse; 51eb45: 48 83 ff 08 cmp $0x8,%rdi 51eb49: 0f 84 f9 00 00 00 je 51ec48 <rb_reg_match_m_p+0x168> str = SYMBOL_P(str) ? rb_sym2str(str) : rb_str_to_str(str); 51eb4f: 40 80 ff 0c cmp $0xc,%dil 51eb53: 0f 84 cf 01 00 00 je 51ed28 <rb_reg_match_m_p+0x248> 51eb59: 40 f6 c7 07 test $0x7,%dil 51eb5d: 75 17 jne 51eb76 <rb_reg_match_m_p+0x96> 51eb5f: 48 f7 c7 f7 ff ff ff test $0xfffffffffffffff7,%rdi 51eb66: 74 0e je 51eb76 <rb_reg_match_m_p+0x96> 51eb68: 8b 07 mov (%rdi),%eax 51eb6a: 83 e0 1f and $0x1f,%eax 51eb6d: 83 f8 14 cmp $0x14,%eax 51eb70: 0f 84 b2 01 00 00 je 51ed28 <rb_reg_match_m_p+0x248> 51eb76: e8 05 72 04 00 callq 565d80 <rb_str_to_str> 51eb7b: 49 89 c4 mov %rax,%r12 

Naruse, I see this was reverted? any way to get rb_scan_args inlined it would be beneficial everywhere.

Nobu, keep in mind your test is looking at 100% hit rate on global method cache, if match? is evicted due to global method cache being open benefit will be greater.

I think this is a great change and hope you can merge in (also =~ is in insns afaik anyway so this add parity)

Sam Saffron wrote:

Naruse, I see this was reverted? any way to get rb_scan_args inlined it would be beneficial everywhere.

Reverted and reapplied at r55110.