support rescue event for TracePoint

fix [Feature #19572]

compile.c

@@ -7748,7 +7748,18 @@ compile_resbody(rb_iseq_t *iseq, LINK_ANCHOR *const ret, const NODE *const node,
         }
         ADD_INSNL(ret, line_node, jump, label_miss);
         ADD_LABEL(ret, label_hit);
-        CHECK(COMPILE(ret, "resbody body", resq->nd_body));
+        ADD_TRACE(ret, RUBY_EVENT_RESCUE);
+
+        if (nd_type(resq->nd_body) == NODE_BEGIN && resq->nd_body->nd_body == NULL) {
+            // empty body
+            int lineno = nd_line(resq->nd_body);
+            NODE dummy_line_node = generate_dummy_line_node(lineno, -1);
+            ADD_INSN(ret, &dummy_line_node, putnil);
+        }
+        else {
+            CHECK(COMPILE(ret, "resbody body", resq->nd_body));
+        }
+
         if (ISEQ_COMPILE_DATA(iseq)->option->tailcall_optimization) {
             ADD_INSN(ret, line_node, nop);
         }
@@ -10406,6 +10417,7 @@ event_name_to_flag(VALUE sym)
                 CHECK_EVENT(RUBY_EVENT_RETURN);
                 CHECK_EVENT(RUBY_EVENT_B_CALL);
                 CHECK_EVENT(RUBY_EVENT_B_RETURN);
+                CHECK_EVENT(RUBY_EVENT_RESCUE);
 #undef CHECK_EVENT
     return RUBY_EVENT_NONE;
 }

include/ruby/internal/event.h

@@ -58,6 +58,7 @@
 #define RUBY_EVENT_THREAD_END        0x0800 /**< Encountered an end of a thread. */
 #define RUBY_EVENT_FIBER_SWITCH      0x1000 /**< Encountered a `Fiber#yield`. */
 #define RUBY_EVENT_SCRIPT_COMPILED   0x2000 /**< Encountered an `eval`. */
+#define RUBY_EVENT_RESCUE            0x4000 /**< Encountered a `rescue` statement. */
 #define RUBY_EVENT_TRACEPOINT_ALL    0xffff /**< Bitmask of extended events. */
 
 /** @} */

iseq.c

@@ -2219,7 +2219,7 @@ rb_iseq_disasm_insn(VALUE ret, const VALUE *code, size_t pos,
     {
         rb_event_flag_t events = rb_iseq_event_flags(iseq, pos);
         if (events) {
-            str = rb_str_catf(str, "[%s%s%s%s%s%s%s%s%s%s%s]",
+            str = rb_str_catf(str, "[%s%s%s%s%s%s%s%s%s%s%s%s]",
                               events & RUBY_EVENT_LINE     ? "Li" : "",
                               events & RUBY_EVENT_CLASS    ? "Cl" : "",
                               events & RUBY_EVENT_END      ? "En" : "",
@@ -2229,6 +2229,7 @@ rb_iseq_disasm_insn(VALUE ret, const VALUE *code, size_t pos,
                               events & RUBY_EVENT_C_RETURN ? "Cr" : "",
                               events & RUBY_EVENT_B_CALL   ? "Bc" : "",
                               events & RUBY_EVENT_B_RETURN ? "Br" : "",
+                              events & RUBY_EVENT_RESCUE   ? "Rs" : "",
                               events & RUBY_EVENT_COVERAGE_LINE   ? "Cli" : "",
                               events & RUBY_EVENT_COVERAGE_BRANCH ? "Cbr" : "");
         }
@@ -2573,6 +2574,7 @@ push_event_info(const rb_iseq_t *iseq, rb_event_flag_t events, int line, VALUE a
     C(RUBY_EVENT_END,      "end",      INT2FIX(line));
     C(RUBY_EVENT_RETURN,   "return",   INT2FIX(line));
     C(RUBY_EVENT_B_RETURN, "b_return", INT2FIX(line));
+    C(RUBY_EVENT_RESCUE,    "rescue",  INT2FIX(line));
 #undef C
 }
 
@@ -3090,6 +3092,7 @@ iseq_data_to_ary(const rb_iseq_t *iseq)
             CHECK_EVENT(RUBY_EVENT_RETURN);
             CHECK_EVENT(RUBY_EVENT_B_CALL);
             CHECK_EVENT(RUBY_EVENT_B_RETURN);
+            CHECK_EVENT(RUBY_EVENT_RESCUE);
 #undef CHECK_EVENT
             prev_insn_info = info;
         }

iseq.h

@@ -83,9 +83,10 @@ ISEQ_ORIGINAL_ISEQ_ALLOC(const rb_iseq_t *iseq, long size)
                            RUBY_EVENT_CALL  | \
                            RUBY_EVENT_RETURN| \
                            RUBY_EVENT_C_CALL| \
-                           RUBY_EVENT_C_RETURN| \
-                           RUBY_EVENT_B_CALL| \
-                           RUBY_EVENT_B_RETURN| \
+                           RUBY_EVENT_C_RETURN | \
+                           RUBY_EVENT_B_CALL   | \
+                           RUBY_EVENT_B_RETURN | \
+                           RUBY_EVENT_RESCUE   | \
                            RUBY_EVENT_COVERAGE_LINE| \
                            RUBY_EVENT_COVERAGE_BRANCH)
 

test/ruby/test_iseq.rb

@@ -497,7 +497,8 @@ def test_trace_points
                                   [7, :line],
                                   [9, :return]]],
                        [["ensure in foo@2", [[7, :line]]]],
-                       [["rescue in foo@4", [[5, :line]]]]]],
+                       [["rescue in foo@4", [[5, :line],
+                                             [5, :rescue]]]]]],
                    [["<class:D>@17", [[17, :class],
                                       [18, :end]]]]], collect_iseq.call(sample_iseq)
   end

test/ruby/test_settracefunc.rb

@@ -2749,4 +2749,51 @@ def test_tp_rescue
     raise_line = lines.shift
     assert_equal [], lines
   end
+
+  def helper_can_rescue
+    begin
+      raise __LINE__.to_s
+    rescue SyntaxError
+      :ng
+    rescue
+      :ok
+    end
+  end
+
+  def helper_can_rescue_empty_body
+    begin
+      raise __LINE__.to_s
+    rescue SyntaxError
+      :ng
+    rescue
+    end
+  end
+
+  def test_tp_rescue_event
+    lines = []
+    TracePoint.new(:rescue){|tp|
+      next unless target_thread?
+      lines << [tp.lineno, tp.raised_exception]
+    }.enable{
+      helper_can_rescue
+    }
+
+    line, err, = lines.pop
+    assert_equal [], lines
+    assert err.kind_of?(RuntimeError)
+    assert_equal err.message.to_i + 4, line
+
+    lines = []
+    TracePoint.new(:rescue){|tp|
+      next unless target_thread?
+      lines << [tp.lineno, tp.raised_exception]
+    }.enable{
+      helper_can_rescue_empty_body
+    }
+
+    line, err, = lines.pop
+    assert_equal [], lines
+    assert err.kind_of?(RuntimeError)
+    assert_equal err.message.to_i + 3, line
+  end
 end

vm_insnhelper.c

@@ -6483,6 +6483,14 @@ rb_vm_opt_cfunc_p(CALL_CACHE cc, int insn)
     } \
 } while (0)
 
+static VALUE
+rescue_errinfo(rb_execution_context_t *ec, rb_control_frame_t *cfp)
+{
+    VM_ASSERT(VM_FRAME_RUBYFRAME_P(cfp));
+    VM_ASSERT(ISEQ_BODY(cfp->iseq)->type == ISEQ_TYPE_RESCUE);
+    return cfp->ep[VM_ENV_INDEX_LAST_LVAR];
+}
+
 static void
 vm_trace(rb_execution_context_t *ec, rb_control_frame_t *reg_cfp)
 {
@@ -6559,6 +6567,7 @@ vm_trace(rb_execution_context_t *ec, rb_control_frame_t *reg_cfp)
                 vm_trace_hook(ec, reg_cfp, pc, RUBY_EVENT_CALL, RUBY_EVENT_CALL, global_hooks, bmethod_local_hooks_ptr, Qundef);
             }
             VM_TRACE_HOOK(RUBY_EVENT_CLASS | RUBY_EVENT_CALL | RUBY_EVENT_B_CALL,   Qundef);
+            VM_TRACE_HOOK(RUBY_EVENT_RESCUE,                                        rescue_errinfo(ec, reg_cfp));
             VM_TRACE_HOOK(RUBY_EVENT_LINE,                                          Qundef);
             VM_TRACE_HOOK(RUBY_EVENT_COVERAGE_LINE,                                 Qundef);
             VM_TRACE_HOOK(RUBY_EVENT_COVERAGE_BRANCH,                               Qundef);

vm_trace.c

@@ -681,6 +681,7 @@ get_event_id(rb_event_flag_t event)
         C(thread_end, THREAD_END);
         C(fiber_switch, FIBER_SWITCH);
         C(script_compiled, SCRIPT_COMPILED);
+        C(rescue, RESCUE);
 #undef C
       default:
         return 0;
@@ -697,8 +698,8 @@ get_path_and_lineno(const rb_execution_context_t *ec, const rb_control_frame_t *
         *pathp = rb_iseq_path(iseq);
 
         if (event & (RUBY_EVENT_CLASS |
-                                RUBY_EVENT_CALL  |
-                                RUBY_EVENT_B_CALL)) {
+                     RUBY_EVENT_CALL  |
+                     RUBY_EVENT_B_CALL)) {
             *linep = FIX2INT(rb_iseq_first_lineno(iseq));
         }
         else {
@@ -823,6 +824,7 @@ symbol2event_flag(VALUE v)
     C(thread_end, THREAD_END);
     C(fiber_switch, FIBER_SWITCH);
     C(script_compiled, SCRIPT_COMPILED);
+    C(rescue, RESCUE);
 
     /* joke */
     C(a_call, A_CALL);
@@ -943,6 +945,7 @@ rb_tracearg_parameters(rb_trace_arg_t *trace_arg)
       case RUBY_EVENT_CLASS:
       case RUBY_EVENT_END:
       case RUBY_EVENT_SCRIPT_COMPILED:
+      case RUBY_EVENT_RESCUE:
         rb_raise(rb_eRuntimeError, "not supported by this event");
         break;
     }
@@ -1013,7 +1016,7 @@ rb_tracearg_return_value(rb_trace_arg_t *trace_arg)
 VALUE
 rb_tracearg_raised_exception(rb_trace_arg_t *trace_arg)
 {
-    if (trace_arg->event & (RUBY_EVENT_RAISE)) {
+    if (trace_arg->event & (RUBY_EVENT_RAISE | RUBY_EVENT_RESCUE)) {
         /* ok */
     }
     else {