Add debug counters to RubyVM.stat (#6086)

* Add debug counters to RubyVM.stat

* Use SIZET2NUM

Co-author: Nobuyoshi Nakada <nobu@ruby-lang.org>

* Prefix debug_counter_names

1 files changed, 19 insertions, 0 deletions

diff --git a/vm.c b/vm.c
index 3181f97123..d62b2f0d48 100644
--- a/vm.c
+++ b/vm.c
@@ -66,6 +66,8 @@ MJIT_FUNC_EXPORTED
 #endif
 VALUE vm_exec(rb_execution_context_t *, bool);
 
+extern const char *const rb_debug_counter_names[];
+
 PUREFUNC(static inline const VALUE *VM_EP_LEP(const VALUE *));
 static inline const VALUE *
 VM_EP_LEP(const VALUE *ep)
@@ -578,6 +580,8 @@ rb_dtrace_setup(rb_execution_context_t *ec, VALUE klass, ID id,
  *      :global_cvar_state=>27
  *    }
  *
+ *  If <tt>USE_DEBUG_COUNTER</tt> is enabled, debug counters will be included.
+ *
  *  The contents of the hash are implementation specific and may be changed in
  *  the future.
  *
@@ -622,6 +626,21 @@ vm_stat(int argc, VALUE *argv, VALUE self)
     SET(next_shape_id, (rb_serial_t)GET_VM()->next_shape_id);
 #undef SET
 
+#if USE_DEBUG_COUNTER
+    ruby_debug_counter_show_at_exit(FALSE);
+    for (size_t i = 0; i < RB_DEBUG_COUNTER_MAX; i++) {
+        const VALUE name = rb_sym_intern_ascii_cstr(rb_debug_counter_names[i]);
+        const VALUE boxed_value = SIZET2NUM(rb_debug_counter[i]);
+
+        if (key == name) {
+            return boxed_value;
+        }
+        else if (hash != Qnil) {
+            rb_hash_aset(hash, name, boxed_value);
+        }
+    }
+#endif
+
     if (!NIL_P(key)) { /* matched key should return above */
         rb_raise(rb_eArgError, "unknown key: %"PRIsVALUE, rb_sym2str(key));
     }