YJIT: Count throw instructions for each tag (#8188)

* YJIT: Count throw instructions for each tag

* Show % of each throw type

4 files changed, 30 insertions, 0 deletions

diff --git a/yjit/bindgen/src/main.rs b/yjit/bindgen/src/main.rs
index 29f39a7cb4..8a187bf674 100644
--- a/yjit/bindgen/src/main.rs
+++ b/yjit/bindgen/src/main.rs
@@ -290,6 +290,8 @@ fn main() {
         .allowlist_var("VM_ENV_DATA_SIZE")
         .allowlist_function("rb_iseq_path")
         .allowlist_type("rb_builtin_attr")
+        .allowlist_type("ruby_tag_type")
+        .allowlist_type("ruby_vm_throw_flags")
 
         // From yjit.c
         .allowlist_function("rb_iseq_(get|set)_yjit_payload")
diff --git a/yjit/src/codegen.rs b/yjit/src/codegen.rs
index 374fdddf3d..4776ff8ce8 100644
--- a/yjit/src/codegen.rs
+++ b/yjit/src/codegen.rs
@@ -3875,6 +3875,15 @@ fn gen_throw(
     let throwobj = asm.stack_pop(1);
     let throwobj = asm.load(throwobj);
 
+    // Gather some statistics about throw
+    gen_counter_incr(asm, Counter::num_throw);
+    match (throw_state & VM_THROW_STATE_MASK as u64) as u32 {
+        RUBY_TAG_BREAK => gen_counter_incr(asm, Counter::num_throw_break),
+        RUBY_TAG_RETRY => gen_counter_incr(asm, Counter::num_throw_retry),
+        RUBY_TAG_RETURN => gen_counter_incr(asm, Counter::num_throw_return),
+        _ => {},
+    }
+
     // THROW_DATA_NEW allocates. Save SP for GC and PC for allocation tracing as
     // well as handling the catch table. However, not using jit_prepare_routine_call
     // since we don't need a patch point for this implementation.
diff --git a/yjit/src/cruby_bindings.inc.rs b/yjit/src/cruby_bindings.inc.rs
index 5f0601f988..91326444ce 100644
--- a/yjit/src/cruby_bindings.inc.rs
+++ b/yjit/src/cruby_bindings.inc.rs
@@ -621,6 +621,20 @@ pub struct rb_id_table {
     _unused: [u8; 0],
 }
 pub type rb_num_t = ::std::os::raw::c_ulong;
+pub const RUBY_TAG_NONE: ruby_tag_type = 0;
+pub const RUBY_TAG_RETURN: ruby_tag_type = 1;
+pub const RUBY_TAG_BREAK: ruby_tag_type = 2;
+pub const RUBY_TAG_NEXT: ruby_tag_type = 3;
+pub const RUBY_TAG_RETRY: ruby_tag_type = 4;
+pub const RUBY_TAG_REDO: ruby_tag_type = 5;
+pub const RUBY_TAG_RAISE: ruby_tag_type = 6;
+pub const RUBY_TAG_THROW: ruby_tag_type = 7;
+pub const RUBY_TAG_FATAL: ruby_tag_type = 8;
+pub const RUBY_TAG_MASK: ruby_tag_type = 15;
+pub type ruby_tag_type = u32;
+pub const VM_THROW_NO_ESCAPE_FLAG: ruby_vm_throw_flags = 32768;
+pub const VM_THROW_STATE_MASK: ruby_vm_throw_flags = 255;
+pub type ruby_vm_throw_flags = u32;
 #[repr(C)]
 pub struct iseq_inline_constant_cache_entry {
     pub flags: VALUE,
diff --git a/yjit/src/stats.rs b/yjit/src/stats.rs
index 620a038e32..035564c40d 100644
--- a/yjit/src/stats.rs
+++ b/yjit/src/stats.rs
@@ -425,6 +425,11 @@ make_counters! {
     num_getivar_megamorphic,
     num_setivar_megamorphic,
 
+    num_throw,
+    num_throw_break,
+    num_throw_retry,
+    num_throw_return,
+
     iseq_stack_too_large,
     iseq_too_long,