From: Ken Jin <28750310+Fidget-Spinner@users.noreply.github.com>
Date: Mon, 20 Oct 2025 23:52:56 +0000 (+0100)
Subject: Fix a bug with where the executors get inserted during EXTENDED_ARG
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=dd0e16f7e1eeb32de05d335502cd1a628508f8c2;p=thirdparty%2FPython%2Fcpython.git

Fix a bug with where the executors get inserted during EXTENDED_ARG
---

diff --git a/Include/internal/pycore_uop.h b/Include/internal/pycore_uop.h
index 86bea31204ca..bccc0b00a4d2 100644
--- a/Include/internal/pycore_uop.h
+++ b/Include/internal/pycore_uop.h
@@ -36,7 +36,7 @@ typedef struct _PyUOpInstruction{
 } _PyUOpInstruction;
 
 // This is the length of the trace we translate initially.
-#define UOP_MAX_TRACE_LENGTH 1400
+#define UOP_MAX_TRACE_LENGTH 1500
 #define UOP_BUFFER_SIZE (UOP_MAX_TRACE_LENGTH * sizeof(_PyUOpInstruction))
 
 /* Bloom filter with m = 256
diff --git a/Python/bytecodes.c b/Python/bytecodes.c
index 0ba8286fc467..7df899dc50e8 100644
--- a/Python/bytecodes.c
+++ b/Python/bytecodes.c
@@ -2979,7 +2979,13 @@ dummy_func(
                 }
                 int _is_sys_tracing = (tstate->c_tracefunc != NULL) || (tstate->c_profilefunc != NULL);
                 if (!_is_sys_tracing) {
-                    _PyJIT_InitializeTracing(tstate, frame, this_instr, next_instr, STACK_LEVEL(), 0, NULL);
+                    /* Back up over EXTENDED_ARGs so executor is inserted at the corret place */
+                    _Py_CODEUNIT *insert_exec_at = this_instr;
+                    while (oparg > 255) {
+                        oparg >>= 8;
+                        insert_exec_at--;
+                    }
+                    _PyJIT_InitializeTracing(tstate, frame, insert_exec_at, next_instr, STACK_LEVEL(), 0, NULL);
                     ENTER_TRACING();
                 }
                 int _jump_taken = false;
diff --git a/Python/generated_cases.c.h b/Python/generated_cases.c.h
index 28691b2c5c83..5cd7142adb33 100644
--- a/Python/generated_cases.c.h
+++ b/Python/generated_cases.c.h
@@ -7671,7 +7671,12 @@
                     }
                     int _is_sys_tracing = (tstate->c_tracefunc != NULL) || (tstate->c_profilefunc != NULL);
                     if (!_is_sys_tracing) {
-                        _PyJIT_InitializeTracing(tstate, frame, this_instr, next_instr, STACK_LEVEL(), 0, NULL);
+                        _Py_CODEUNIT *insert_exec_at = this_instr;
+                        while (oparg > 255) {
+                            oparg >>= 8;
+                            insert_exec_at--;
+                        }
+                        _PyJIT_InitializeTracing(tstate, frame, insert_exec_at, next_instr, STACK_LEVEL(), 0, NULL);
                         ENTER_TRACING();
                     }
                     int _jump_taken = false;
diff --git a/Python/generated_tracer_cases.c.h b/Python/generated_tracer_cases.c.h
index 9d739dc00db9..759bfd13cb83 100644
--- a/Python/generated_tracer_cases.c.h
+++ b/Python/generated_tracer_cases.c.h
@@ -8956,7 +8956,12 @@
                     }
                     int _is_sys_tracing = (tstate->c_tracefunc != NULL) || (tstate->c_profilefunc != NULL);
                     if (!_is_sys_tracing) {
-                        _PyJIT_InitializeTracing(tstate, frame, this_instr, next_instr, STACK_LEVEL(), 0, NULL);
+                        _Py_CODEUNIT *insert_exec_at = this_instr;
+                        while (oparg > 255) {
+                            oparg >>= 8;
+                            insert_exec_at--;
+                        }
+                        _PyJIT_InitializeTracing(tstate, frame, insert_exec_at, next_instr, STACK_LEVEL(), 0, NULL);
                         ENTER_TRACING();
                     }
                     int _jump_taken = false;