YJIT: don't compile attr_accessor methods when tracing (#4998)

2d98593bf54a37397c6e4886ccc7e3654c2eaf85 made it so that
attr_accessor methods fire C method tracing events.
Previously, we weren't checking for whether we are tracing before
compiling, leading to missed events.

Since global invalidation invalidates all code, and that attr_accessor
methods can never enable tracing while running, events are only dropped
when YJIT tries to compile when tracing is already enabled.

Factor out the code for checking tracing and check it before generating
code for attr_accessor methods.

This change fixes TestSetTraceFunc#test_tracepoint_attr when it's
ran in isolation.

1 files changed, 50 insertions, 0 deletions

diff --git a/bootstraptest/test_yjit.rb b/bootstraptest/test_yjit.rb
index a58ff2d18f..53cdcc69ac 100644
--- a/bootstraptest/test_yjit.rb
+++ b/bootstraptest/test_yjit.rb
@@ -2214,3 +2214,53 @@ assert_equal 'ok', %q{
 
   :ok
 }
+
+# regression test for tracing attr_accessor methods.
+assert_equal "true", %q{
+    c = Class.new do
+      attr_accessor :x
+      alias y x
+      alias y= x=
+    end
+    obj = c.new
+
+    ar_meth = obj.method(:x)
+    aw_meth = obj.method(:x=)
+    aar_meth = obj.method(:y)
+    aaw_meth = obj.method(:y=)
+    events = []
+    trace = TracePoint.new(:c_call, :c_return){|tp|
+      next if tp.path != __FILE__
+      next if tp.method_id == :call
+      case tp.event
+      when :c_call
+        events << [tp.event, tp.method_id, tp.callee_id]
+      when :c_return
+        events << [tp.event, tp.method_id, tp.callee_id, tp.return_value]
+      end
+    }
+    test_proc = proc do
+      obj.x = 1
+      obj.x
+      obj.y = 2
+      obj.y
+      aw_meth.call(1)
+      ar_meth.call
+      aaw_meth.call(2)
+      aar_meth.call
+    end
+    test_proc.call # populate call caches
+    trace.enable(&test_proc)
+    expected = [
+      [:c_call, :x=, :x=],
+      [:c_return, :x=, :x=, 1],
+      [:c_call, :x, :x],
+      [:c_return, :x, :x, 1],
+      [:c_call, :x=, :y=],
+      [:c_return, :x=, :y=, 2],
+      [:c_call, :x, :y],
+      [:c_return, :x, :y, 2],
+    ] * 2
+
+    expected == events
+}