ZJIT: Profile opt_size, opt_length, opt_regexpmatch2 (#14837)

These bring `send_without_block_no_profiles` numbers down more.

On lobsters:
  Before:  send_without_block_no_profiles: 1,293,375
  After:   send_without_block_no_profiles: 998,724

all stats before:

```
***ZJIT: Printing ZJIT statistics on exit***
Top-20 not inlined C methods (71.1% of total 15,575,335):
                                    Hash#[]: 4,519,774 (29.0%)
                               Kernel#is_a?: 1,030,758 ( 6.6%)
                                  String#<<:   851,929 ( 5.5%)
                                   Hash#[]=:   742,941 ( 4.8%)
                              Regexp#match?:   399,889 ( 2.6%)
                              String#empty?:   353,775 ( 2.3%)
                                  Hash#key?:   349,129 ( 2.2%)
                         String#start_with?:   334,961 ( 2.2%)
                         Kernel#respond_to?:   316,527 ( 2.0%)
                 ObjectSpace::WeakKeyMap#[]:   238,978 ( 1.5%)
                              TrueClass#===:   235,771 ( 1.5%)
                             FalseClass#===:   231,144 ( 1.5%)
                             Array#include?:   211,381 ( 1.4%)
                                 Hash#fetch:   204,702 ( 1.3%)
                        Kernel#block_given?:   181,792 ( 1.2%)
         ActiveSupport::OrderedOptions#_get:   181,272 ( 1.2%)
                                 Kernel#dup:   179,340 ( 1.2%)
                             BasicObject#!=:   175,997 ( 1.1%)
                                  Class#new:   168,078 ( 1.1%)
                            Kernel#kind_of?:   165,600 ( 1.1%)
Top-20 not annotated C methods (71.6% of total 15,737,478):
                                    Hash#[]: 4,519,784 (28.7%)
                               Kernel#is_a?: 1,212,649 ( 7.7%)
                                  String#<<:   851,929 ( 5.4%)
                                   Hash#[]=:   743,120 ( 4.7%)
                              Regexp#match?:   399,889 ( 2.5%)
                              String#empty?:   361,013 ( 2.3%)
                                  Hash#key?:   349,129 ( 2.2%)
                         String#start_with?:   334,961 ( 2.1%)
                         Kernel#respond_to?:   316,527 ( 2.0%)
                 ObjectSpace::WeakKeyMap#[]:   238,978 ( 1.5%)
                              TrueClass#===:   235,771 ( 1.5%)
                             FalseClass#===:   231,144 ( 1.5%)
                             Array#include?:   211,381 ( 1.3%)
                                 Hash#fetch:   204,702 ( 1.3%)
                        Kernel#block_given?:   191,661 ( 1.2%)
         ActiveSupport::OrderedOptions#_get:   181,272 ( 1.2%)
                                 Kernel#dup:   179,347 ( 1.1%)
                             BasicObject#!=:   176,181 ( 1.1%)
                                  Class#new:   168,078 ( 1.1%)
                            Kernel#kind_of?:   165,634 ( 1.1%)
Top-2 not optimized method types for send (100.0% of total 72,318):
  cfunc: 48,055 (66.4%)
   iseq: 24,263 (33.6%)
Top-6 not optimized method types for send_without_block (100.0% of total 4,523,648):
       iseq: 2,271,904 (50.2%)
    bmethod:   985,636 (21.8%)
  optimized:   949,702 (21.0%)
      alias:   310,746 ( 6.9%)
       null:     5,106 ( 0.1%)
      cfunc:       554 ( 0.0%)
Top-13 not optimized instructions (100.0% of total 4,293,096):
             invokesuper: 2,373,391 (55.3%)
             invokeblock:   811,872 (18.9%)
             sendforward:   505,448 (11.8%)
                  opt_eq:   451,754 (10.5%)
                opt_plus:    74,403 ( 1.7%)
               opt_minus:    36,225 ( 0.8%)
  opt_send_without_block:    21,792 ( 0.5%)
                 opt_neq:     7,231 ( 0.2%)
                opt_mult:     6,752 ( 0.2%)
                  opt_or:     3,753 ( 0.1%)
                  opt_lt:       348 ( 0.0%)
                  opt_ge:        91 ( 0.0%)
                  opt_gt:        36 ( 0.0%)
Top-9 send fallback reasons (100.0% of total 25,824,463):
                send_without_block_polymorphic: 9,721,727 (37.6%)
                              send_no_profiles: 5,894,760 (22.8%)
  send_without_block_not_optimized_method_type: 4,523,648 (17.5%)
                     not_optimized_instruction: 4,293,096 (16.6%)
                send_without_block_no_profiles: 1,293,386 ( 5.0%)
                send_not_optimized_method_type:    72,318 ( 0.3%)
       send_without_block_cfunc_array_variadic:    15,134 ( 0.1%)
                      obj_to_string_not_string:     9,765 ( 0.0%)
       send_without_block_direct_too_many_args:       629 ( 0.0%)
Top-9 unhandled YARV insns (100.0% of total 690,482):
         expandarray: 328,490 (47.6%)
        checkkeyword: 190,694 (27.6%)
    getclassvariable:  59,901 ( 8.7%)
  invokesuperforward:  49,503 ( 7.2%)
       getblockparam:  48,651 ( 7.0%)
   opt_duparray_send:  11,978 ( 1.7%)
         getconstant:     952 ( 0.1%)
          checkmatch:     290 ( 0.0%)
                once:      23 ( 0.0%)
Top-3 compile error reasons (100.0% of total 3,752,502):
  register_spill_on_alloc: 3,457,791 (92.1%)
  register_spill_on_ccall:   176,348 ( 4.7%)
        exception_handler:   118,363 ( 3.2%)
Top-14 side exit reasons (100.0% of total 10,860,787):
                        compile_error: 3,752,502 (34.6%)
                   guard_type_failure: 2,638,903 (24.3%)
                  guard_shape_failure: 1,917,195 (17.7%)
                  unhandled_yarv_insn:   690,482 ( 6.4%)
  block_param_proxy_not_iseq_or_ifunc:   535,787 ( 4.9%)
                      unhandled_kwarg:   421,943 ( 3.9%)
                           patchpoint:   370,449 ( 3.4%)
                unknown_newarray_send:   314,785 ( 2.9%)
                      unhandled_splat:   122,060 ( 1.1%)
                   unhandled_hir_insn:    76,396 ( 0.7%)
           block_param_proxy_modified:    19,193 ( 0.2%)
               obj_to_string_fallback:       566 ( 0.0%)
                            interrupt:       504 ( 0.0%)
               guard_type_not_failure:        22 ( 0.0%)
                             send_count: 66,945,801
                     dynamic_send_count: 25,824,463 (38.6%)
                   optimized_send_count: 41,121,338 (61.4%)
              iseq_optimized_send_count: 18,587,368 (27.8%)
      inline_cfunc_optimized_send_count:  6,958,635 (10.4%)
non_variadic_cfunc_optimized_send_count: 12,911,155 (19.3%)
    variadic_cfunc_optimized_send_count:  2,664,180 ( 4.0%)
dynamic_getivar_count:                        7,365,975
dynamic_setivar_count:                        7,245,897
compiled_iseq_count:                              4,794
failed_iseq_count:                                  450
compile_time:                                     760ms
profile_time:                                       9ms
gc_time:                                            8ms
invalidation_time:                                 55ms
vm_write_pc_count:                           64,284,053
vm_write_sp_count:                           62,940,297
vm_write_locals_count:                       62,940,297
vm_write_stack_count:                        62,940,297
vm_write_to_parent_iseq_local_count:            292,446
vm_read_from_parent_iseq_local_count:         6,470,923
code_region_bytes:                           23,019,520
side_exit_count:                             10,860,787
total_insn_count:                           517,576,320
vm_insn_count:                              163,188,910
zjit_insn_count:                            354,387,410
ratio_in_zjit:                                    68.5%
```

all stats after:

```
***ZJIT: Printing ZJIT statistics on exit***
Top-20 not inlined C methods (70.4% of total 15,740,856):
                                    Hash#[]: 4,519,792 (28.7%)
                               Kernel#is_a?: 1,030,776 ( 6.5%)
                                  String#<<:   851,940 ( 5.4%)
                                   Hash#[]=:   742,914 ( 4.7%)
                              Regexp#match?:   399,887 ( 2.5%)
                              String#empty?:   353,775 ( 2.2%)
                                  Hash#key?:   349,139 ( 2.2%)
                         String#start_with?:   334,961 ( 2.1%)
                         Kernel#respond_to?:   316,529 ( 2.0%)
                 ObjectSpace::WeakKeyMap#[]:   238,978 ( 1.5%)
                              TrueClass#===:   235,771 ( 1.5%)
                             FalseClass#===:   231,144 ( 1.5%)
                             Array#include?:   211,381 ( 1.3%)
                                 Hash#fetch:   204,702 ( 1.3%)
                        Kernel#block_given?:   181,788 ( 1.2%)
         ActiveSupport::OrderedOptions#_get:   181,272 ( 1.2%)
                                 Kernel#dup:   179,341 ( 1.1%)
                             BasicObject#!=:   175,996 ( 1.1%)
                                  Class#new:   168,079 ( 1.1%)
                            Kernel#kind_of?:   165,600 ( 1.1%)
Top-20 not annotated C methods (70.9% of total 15,902,999):
                                    Hash#[]: 4,519,802 (28.4%)
                               Kernel#is_a?: 1,212,667 ( 7.6%)
                                  String#<<:   851,940 ( 5.4%)
                                   Hash#[]=:   743,093 ( 4.7%)
                              Regexp#match?:   399,887 ( 2.5%)
                              String#empty?:   361,013 ( 2.3%)
                                  Hash#key?:   349,139 ( 2.2%)
                         String#start_with?:   334,961 ( 2.1%)
                         Kernel#respond_to?:   316,529 ( 2.0%)
                 ObjectSpace::WeakKeyMap#[]:   238,978 ( 1.5%)
                              TrueClass#===:   235,771 ( 1.5%)
                             FalseClass#===:   231,144 ( 1.5%)
                             Array#include?:   211,381 ( 1.3%)
                                 Hash#fetch:   204,702 ( 1.3%)
                        Kernel#block_given?:   191,657 ( 1.2%)
         ActiveSupport::OrderedOptions#_get:   181,272 ( 1.1%)
                                 Kernel#dup:   179,348 ( 1.1%)
                             BasicObject#!=:   176,180 ( 1.1%)
                                  Class#new:   168,079 ( 1.1%)
                            Kernel#kind_of?:   165,634 ( 1.0%)
Top-2 not optimized method types for send (100.0% of total 72,318):
  cfunc: 48,055 (66.4%)
   iseq: 24,263 (33.6%)
Top-6 not optimized method types for send_without_block (100.0% of total 4,523,637):
       iseq: 2,271,900 (50.2%)
    bmethod:   985,636 (21.8%)
  optimized:   949,695 (21.0%)
      alias:   310,746 ( 6.9%)
       null:     5,106 ( 0.1%)
      cfunc:       554 ( 0.0%)
Top-13 not optimized instructions (100.0% of total 4,293,128):
             invokesuper: 2,373,401 (55.3%)
             invokeblock:   811,890 (18.9%)
             sendforward:   505,449 (11.8%)
                  opt_eq:   451,754 (10.5%)
                opt_plus:    74,403 ( 1.7%)
               opt_minus:    36,228 ( 0.8%)
  opt_send_without_block:    21,792 ( 0.5%)
                 opt_neq:     7,231 ( 0.2%)
                opt_mult:     6,752 ( 0.2%)
                  opt_or:     3,753 ( 0.1%)
                  opt_lt:       348 ( 0.0%)
                  opt_ge:        91 ( 0.0%)
                  opt_gt:        36 ( 0.0%)
Top-9 send fallback reasons (100.0% of total 25,530,605):
                send_without_block_polymorphic: 9,722,499 (38.1%)
                              send_no_profiles: 5,894,763 (23.1%)
  send_without_block_not_optimized_method_type: 4,523,637 (17.7%)
                     not_optimized_instruction: 4,293,128 (16.8%)
                send_without_block_no_profiles:   998,732 ( 3.9%)
                send_not_optimized_method_type:    72,318 ( 0.3%)
       send_without_block_cfunc_array_variadic:    15,134 ( 0.1%)
                      obj_to_string_not_string:     9,765 ( 0.0%)
       send_without_block_direct_too_many_args:       629 ( 0.0%)
Top-9 unhandled YARV insns (100.0% of total 690,482):
         expandarray: 328,490 (47.6%)
        checkkeyword: 190,694 (27.6%)
    getclassvariable:  59,901 ( 8.7%)
  invokesuperforward:  49,503 ( 7.2%)
       getblockparam:  48,651 ( 7.0%)
   opt_duparray_send:  11,978 ( 1.7%)
         getconstant:     952 ( 0.1%)
          checkmatch:     290 ( 0.0%)
                once:      23 ( 0.0%)
Top-3 compile error reasons (100.0% of total 3,752,500):
  register_spill_on_alloc: 3,457,792 (92.1%)
  register_spill_on_ccall:   176,348 ( 4.7%)
        exception_handler:   118,360 ( 3.2%)
Top-14 side exit reasons (100.0% of total 10,860,797):
                        compile_error: 3,752,500 (34.6%)
                   guard_type_failure: 2,638,909 (24.3%)
                  guard_shape_failure: 1,917,203 (17.7%)
                  unhandled_yarv_insn:   690,482 ( 6.4%)
  block_param_proxy_not_iseq_or_ifunc:   535,784 ( 4.9%)
                      unhandled_kwarg:   421,947 ( 3.9%)
                           patchpoint:   370,474 ( 3.4%)
                unknown_newarray_send:   314,786 ( 2.9%)
                      unhandled_splat:   122,067 ( 1.1%)
                   unhandled_hir_insn:    76,395 ( 0.7%)
           block_param_proxy_modified:    19,193 ( 0.2%)
               obj_to_string_fallback:       566 ( 0.0%)
                            interrupt:       469 ( 0.0%)
               guard_type_not_failure:        22 ( 0.0%)
                             send_count: 66,945,326
                     dynamic_send_count: 25,530,605 (38.1%)
                   optimized_send_count: 41,414,721 (61.9%)
              iseq_optimized_send_count: 18,587,439 (27.8%)
      inline_cfunc_optimized_send_count:  7,086,426 (10.6%)
non_variadic_cfunc_optimized_send_count: 13,076,682 (19.5%)
    variadic_cfunc_optimized_send_count:  2,664,174 ( 4.0%)
dynamic_getivar_count:                       7,365,985
dynamic_setivar_count:                       7,245,954
compiled_iseq_count:                             4,794
failed_iseq_count:                                 450
compile_time:                                    748ms
profile_time:                                      9ms
gc_time:                                           8ms
invalidation_time:                                58ms
vm_write_pc_count:                          64,155,801
vm_write_sp_count:                          62,812,041
vm_write_locals_count:                      62,812,041
vm_write_stack_count:                       62,812,041
vm_write_to_parent_iseq_local_count:           292,448
vm_read_from_parent_iseq_local_count:        6,470,939
code_region_bytes:                          23,052,288
side_exit_count:                            10,860,797
total_insn_count:                          517,576,915
vm_insn_count:                             163,192,099
zjit_insn_count:                           354,384,816
ratio_in_zjit:                                   68.5%
```

4 files changed, 96 insertions, 4 deletions

diff --git a/insns.def b/insns.def
index b895bffe22..69a8210d7d 100644
--- a/insns.def
+++ b/insns.def
@@ -1553,6 +1553,7 @@ opt_length
 (CALL_DATA cd)
 (VALUE recv)
 (VALUE val)
+// attr bool zjit_profile = true;
 {
     val = vm_opt_length(recv, BOP_LENGTH);
 
@@ -1567,6 +1568,7 @@ opt_size
 (CALL_DATA cd)
 (VALUE recv)
 (VALUE val)
+// attr bool zjit_profile = true;
 {
     val = vm_opt_length(recv, BOP_SIZE);
 
@@ -1626,6 +1628,7 @@ opt_regexpmatch2
 (VALUE obj2, VALUE obj1)
 (VALUE val)
 // attr bool leaf = false; /* match_at() has rb_thread_check_ints() */
+// attr bool zjit_profile = true;
 {
     val = vm_opt_regexpmatch2(obj2, obj1);
 
diff --git a/zjit/src/cruby_bindings.inc.rs b/zjit/src/cruby_bindings.inc.rs
index 6e3ae05194..56b569e064 100644
--- a/zjit/src/cruby_bindings.inc.rs
+++ b/zjit/src/cruby_bindings.inc.rs
@@ -699,9 +699,12 @@ pub const YARVINSN_zjit_opt_and: ruby_vminsn_type = 234;
 pub const YARVINSN_zjit_opt_or: ruby_vminsn_type = 235;
 pub const YARVINSN_zjit_opt_aref: ruby_vminsn_type = 236;
 pub const YARVINSN_zjit_opt_aset: ruby_vminsn_type = 237;
-pub const YARVINSN_zjit_opt_empty_p: ruby_vminsn_type = 238;
-pub const YARVINSN_zjit_opt_not: ruby_vminsn_type = 239;
-pub const VM_INSTRUCTION_SIZE: ruby_vminsn_type = 240;
+pub const YARVINSN_zjit_opt_length: ruby_vminsn_type = 238;
+pub const YARVINSN_zjit_opt_size: ruby_vminsn_type = 239;
+pub const YARVINSN_zjit_opt_empty_p: ruby_vminsn_type = 240;
+pub const YARVINSN_zjit_opt_not: ruby_vminsn_type = 241;
+pub const YARVINSN_zjit_opt_regexpmatch2: ruby_vminsn_type = 242;
+pub const VM_INSTRUCTION_SIZE: ruby_vminsn_type = 243;
 pub type ruby_vminsn_type = u32;
 pub type rb_iseq_callback = ::std::option::Option<
     unsafe extern "C" fn(arg1: *const rb_iseq_t, arg2: *mut ::std::os::raw::c_void),
diff --git a/zjit/src/hir.rs b/zjit/src/hir.rs
index 022451e8ab..33c034b819 100644
--- a/zjit/src/hir.rs
+++ b/zjit/src/hir.rs
@@ -4957,7 +4957,7 @@ mod tests {
     }
 
     #[track_caller]
-    fn assert_contains_opcode(method: &str, opcode: u32) {
+    pub fn assert_contains_opcode(method: &str, opcode: u32) {
         let iseq = crate::cruby::with_rubyvm(|| get_method_iseq("self", method));
         unsafe { crate::cruby::rb_zjit_profile_disable(iseq) };
         assert!(iseq_contains_opcode(iseq, opcode), "iseq {method} does not contain {}", insn_name(opcode as usize));
@@ -7999,6 +7999,7 @@ mod opt_tests {
     use super::*;
     use crate::{hir_strings, options::*};
     use insta::assert_snapshot;
+    use super::tests::assert_contains_opcode;
 
     #[track_caller]
     fn hir_string(method: &str) -> String {
@@ -12876,4 +12877,86 @@ mod opt_tests {
           Return v27
         ");
     }
+
+    #[test]
+    fn test_optimize_array_length() {
+        eval("
+            def test(arr) = arr.length
+            test([])
+        ");
+        assert_contains_opcode("test", YARVINSN_opt_length);
+        assert_snapshot!(hir_string("test"), @r"
+        fn test@<compiled>:2:
+        bb0():
+          EntryPoint interpreter
+          v1:BasicObject = LoadSelf
+          v2:BasicObject = GetLocal l0, SP@4
+          Jump bb2(v1, v2)
+        bb1(v5:BasicObject, v6:BasicObject):
+          EntryPoint JIT(0)
+          Jump bb2(v5, v6)
+        bb2(v8:BasicObject, v9:BasicObject):
+          PatchPoint MethodRedefined(Array@0x1000, length@0x1008, cme:0x1010)
+          PatchPoint NoSingletonClass(Array@0x1000)
+          v25:ArrayExact = GuardType v9, ArrayExact
+          v26:Fixnum = CCall length@0x1038, v25
+          CheckInterrupts
+          Return v26
+        ");
+    }
+
+    #[test]
+    fn test_optimize_array_size() {
+        eval("
+            def test(arr) = arr.size
+            test([])
+        ");
+        assert_contains_opcode("test", YARVINSN_opt_size);
+        assert_snapshot!(hir_string("test"), @r"
+        fn test@<compiled>:2:
+        bb0():
+          EntryPoint interpreter
+          v1:BasicObject = LoadSelf
+          v2:BasicObject = GetLocal l0, SP@4
+          Jump bb2(v1, v2)
+        bb1(v5:BasicObject, v6:BasicObject):
+          EntryPoint JIT(0)
+          Jump bb2(v5, v6)
+        bb2(v8:BasicObject, v9:BasicObject):
+          PatchPoint MethodRedefined(Array@0x1000, size@0x1008, cme:0x1010)
+          PatchPoint NoSingletonClass(Array@0x1000)
+          v25:ArrayExact = GuardType v9, ArrayExact
+          v26:Fixnum = CCall size@0x1038, v25
+          CheckInterrupts
+          Return v26
+        ");
+    }
+
+    #[test]
+    fn test_optimize_regexpmatch2() {
+        eval(r#"
+            def test(s) = s =~ /a/
+            test("foo")
+        "#);
+        assert_contains_opcode("test", YARVINSN_opt_regexpmatch2);
+        assert_snapshot!(hir_string("test"), @r"
+        fn test@<compiled>:2:
+        bb0():
+          EntryPoint interpreter
+          v1:BasicObject = LoadSelf
+          v2:BasicObject = GetLocal l0, SP@4
+          Jump bb2(v1, v2)
+        bb1(v5:BasicObject, v6:BasicObject):
+          EntryPoint JIT(0)
+          Jump bb2(v5, v6)
+        bb2(v8:BasicObject, v9:BasicObject):
+          v13:RegexpExact[VALUE(0x1000)] = Const Value(VALUE(0x1000))
+          PatchPoint MethodRedefined(String@0x1008, =~@0x1010, cme:0x1018)
+          PatchPoint NoSingletonClass(String@0x1008)
+          v26:StringExact = GuardType v9, StringExact
+          v27:BasicObject = CCallWithFrame =~@0x1040, v26, v13
+          CheckInterrupts
+          Return v27
+        ");
+    }
 }
diff --git a/zjit/src/profile.rs b/zjit/src/profile.rs
index c2c35f687b..e7db47142b 100644
--- a/zjit/src/profile.rs
+++ b/zjit/src/profile.rs
@@ -78,7 +78,10 @@ fn profile_insn(bare_opcode: ruby_vminsn_type, ec: EcPtr) {
         YARVINSN_opt_aset  => profile_operands(profiler, profile, 3),
         YARVINSN_opt_not   => profile_operands(profiler, profile, 1),
         YARVINSN_getinstancevariable => profile_self(profiler, profile),
+        YARVINSN_opt_regexpmatch2    => profile_operands(profiler, profile, 2),
         YARVINSN_objtostring   => profile_operands(profiler, profile, 1),
+        YARVINSN_opt_length    => profile_operands(profiler, profile, 1),
+        YARVINSN_opt_size      => profile_operands(profiler, profile, 1),
         YARVINSN_opt_send_without_block => {
             let cd: *const rb_call_data = profiler.insn_opnd(0).as_ptr();
             let argc = unsafe { vm_ci_argc((*cd).ci) };