From: Ken Jin <28750310+Fidget-Spinner@users.noreply.github.com>
Date: Thu, 6 Nov 2025 00:14:14 +0000 (+0000)
Subject: Remove _DYNAMIC_EXIT jumping for now.
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=a64215db13c52438f17120018cb026de45514ba3;p=thirdparty%2FPython%2Fcpython.git

Remove _DYNAMIC_EXIT jumping for now.
---

diff --git a/Python/bytecodes.c b/Python/bytecodes.c
index 47b73e30971a..0a45291d4a5d 100644
--- a/Python/bytecodes.c
+++ b/Python/bytecodes.c
@@ -5289,8 +5289,8 @@ dummy_func(
         // Note: this is different than _COLD_EXIT/_EXIT_TRACE, as it may lead to multiple executors
         // from a single exit!
         tier2 op(_DYNAMIC_EXIT, (exit_p/4 --)) {
-            _PyExitData *exit = (_PyExitData *)exit_p;
     #if defined(Py_DEBUG) && !defined(_Py_JIT)
+            _PyExitData *exit = (_PyExitData *)exit_p;
             _Py_CODEUNIT *target = frame->instr_ptr;
             OPT_HIST(trace_uop_execution_counter, trace_run_length_hist);
             if (frame->lltrace >= 2) {
@@ -5302,10 +5302,9 @@ dummy_func(
                     _PyOpcode_OpName[target->op.code]);
             }
     #endif
-            tstate->jit_exit = exit;
-            _PyExecutorObject *exec = exit->executor;
-            assert(exec->trace[0].opcode == _COLD_DYNAMIC_EXIT);
-            TIER2_TO_TIER2(exec);
+            // Disabled for now (gh-139109) as it slows down dynamic code tremendously.
+            // Compile and jump to the cold dynamic executors in the future.
+            GOTO_TIER_ONE(frame->instr_ptr);
         }
 
         tier2 op(_DYNAMIC_DEOPT, (--)) {
@@ -5475,6 +5474,9 @@ dummy_func(
                 PyCodeObject *code = _PyFrame_GetCode(frame);
                 executor = code->co_executors->executors[target->op.arg];
                 Py_INCREF(executor);
+                assert(tstate->jit_exit == exit);
+                exit->executor = executor;
+                TIER2_TO_TIER2(exit->executor);
             }
             else {
                 if (frame->owner >= FRAME_OWNED_BY_INTERPRETER) {
@@ -5499,14 +5501,9 @@ dummy_func(
                 }
                 GOTO_TIER_ONE(target);
             }
-            assert(tstate->jit_exit == exit);
-            exit->executor = executor;
-            TIER2_TO_TIER2(exit->executor);
         }
 
         tier2 op(_COLD_DYNAMIC_EXIT, ( -- )) {
-            _PyExitData *exit = tstate->jit_exit;
-            assert(exit != NULL);
             _Py_CODEUNIT *target = frame->instr_ptr;
             GOTO_TIER_ONE(target);
         }
diff --git a/Python/executor_cases.c.h b/Python/executor_cases.c.h
index 57dc7c6902c3..c6120a346a53 100644
--- a/Python/executor_cases.c.h
+++ b/Python/executor_cases.c.h
@@ -7132,8 +7132,8 @@
 
         case _DYNAMIC_EXIT: {
             PyObject *exit_p = (PyObject *)CURRENT_OPERAND0();
-            _PyExitData *exit = (_PyExitData *)exit_p;
             #if defined(Py_DEBUG) && !defined(_Py_JIT)
+            _PyExitData *exit = (_PyExitData *)exit_p;
             _Py_CODEUNIT *target = frame->instr_ptr;
             OPT_HIST(trace_uop_execution_counter, trace_run_length_hist);
             if (frame->lltrace >= 2) {
@@ -7147,10 +7147,8 @@
                 stack_pointer = _PyFrame_GetStackPointer(frame);
             }
             #endif
-            tstate->jit_exit = exit;
-            _PyExecutorObject *exec = exit->executor;
-            assert(exec->trace[0].opcode == _COLD_DYNAMIC_EXIT);
-            TIER2_TO_TIER2(exec);
+
+            GOTO_TIER_ONE(frame->instr_ptr);
             break;
         }
 
@@ -7523,6 +7521,9 @@
                 PyCodeObject *code = _PyFrame_GetCode(frame);
                 executor = code->co_executors->executors[target->op.arg];
                 Py_INCREF(executor);
+                assert(tstate->jit_exit == exit);
+                exit->executor = executor;
+                TIER2_TO_TIER2(exit->executor);
             }
             else {
                 if (frame->owner >= FRAME_OWNED_BY_INTERPRETER) {
@@ -7542,15 +7543,10 @@
                 }
                 GOTO_TIER_ONE(target);
             }
-            assert(tstate->jit_exit == exit);
-            exit->executor = executor;
-            TIER2_TO_TIER2(exit->executor);
             break;
         }
 
         case _COLD_DYNAMIC_EXIT: {
-            _PyExitData *exit = tstate->jit_exit;
-            assert(exit != NULL);
             _Py_CODEUNIT *target = frame->instr_ptr;
             GOTO_TIER_ONE(target);
             break;