gh-120029: refactor symtable.c (remove deprecated macros and update some values)

Include/internal/pycore_symtable.h

@@ -134,37 +134,44 @@ extern PyObject* _Py_Mangle(PyObject *p, PyObject *name);
 
 /* Flags for def-use information */
 
-#define DEF_GLOBAL 1             /* global stmt */
-#define DEF_LOCAL 2              /* assignment in code block */
-#define DEF_PARAM (2<<1)         /* formal parameter */
-#define DEF_NONLOCAL (2<<2)      /* nonlocal stmt */
-#define USE (2<<3)               /* name is used */
-#define DEF_FREE (2<<4)          /* name used but not defined in nested block */
-#define DEF_FREE_CLASS (2<<5)    /* free variable from class's method */
-#define DEF_IMPORT (2<<6)        /* assignment occurred via import */
-#define DEF_ANNOT (2<<7)         /* this name is annotated */
-#define DEF_COMP_ITER (2<<8)     /* this name is a comprehension iteration variable */
-#define DEF_TYPE_PARAM (2<<9)    /* this name is a type parameter */
-#define DEF_COMP_CELL (2<<10)    /* this name is a cell in an inlined comprehension */
-
-#define DEF_BOUND (DEF_LOCAL | DEF_PARAM | DEF_IMPORT)
-
-/* GLOBAL_EXPLICIT and GLOBAL_IMPLICIT are used internally by the symbol
-   table.  GLOBAL is returned from PyST_GetScope() for either of them.
-   It is stored in ste_symbols at bits 13-16.
-*/
-#define SCOPE_OFFSET 12
-#define SCOPE_MASK (DEF_GLOBAL | DEF_LOCAL | DEF_PARAM | DEF_NONLOCAL)
-
+#define USE             (1 << 0)    /* this name is used */
+#define DEF_ANNOT       (1 << 1)    /* this name is annotated */
+
+#define DEF_IMPORT      (1 << 2)    /* assignment by an 'import' statement */
+#define DEF_GLOBAL      (1 << 3)    /* (re-)declaration by a 'global' statement */
+#define DEF_NONLOCAL    (1 << 4)    /* (re-)declaration by a 'nonlocal' statement */
+#define DEF_LOCAL       (1 << 5)    /* assignment in a code block */
+
+#define DEF_PARAM       (1 << 6)    /* this name is a formal parameter */
+#define DEF_TYPE_PARAM  (1 << 7)    /* this name is a formal type parameter */
+
+#define DEF_FREE_CLASS  (1 << 8)    /* this name is a free from a method perspective */
+#define DEF_COMP_ITER   (1 << 9)    /* this name is a comprehension iteration variable */
+#define DEF_COMP_CELL   (1 << 10)   /* this name is a cell in an inlined comprehension */
+
+#define DEF_BOUND       (DEF_IMPORT | DEF_LOCAL | DEF_PARAM)
+
+// The scope is stored in "ste_symbols" at bits 11, 12 and 13 (bits indexed
+// from 0, from right to left), namely:
+//
+//      ste_symbols = (SCOPE << SCOPE_OFFSET) | DEF_OR_USE_FLAGS
+//
+// Whenever a 'def-use' flag (resp., a 'scope' value) is added or removed,
+// the SCOPE_OFFSET (resp., SCOPE_MASK) value must be changed accordingly.
+#define SCOPE_OFFSET    11          /* 1 + highest bit for a DEF_* flag */
+#define SCOPE_MASK      0b111       /* 3 bits for storing the scope */
+
+// Scopes for a symbol.
+//
+// GLOBAL_EXPLICIT and GLOBAL_IMPLICIT are used internally by the symbol
+// table. For symbols with such scopes, the ``symtable.Symbol.is_global``
+// method returns True.
 #define LOCAL 1
 #define GLOBAL_EXPLICIT 2
 #define GLOBAL_IMPLICIT 3
 #define FREE 4
 #define CELL 5
 
-#define GENERATOR 1
-#define GENERATOR_EXPRESSION 2
-
 // Used by symtablemodule.c
 extern struct symtable* _Py_SymtableStringObjectFlags(
     const char *str,

Lib/importlib/_bootstrap_external.py

@@ -474,6 +474,7 @@ def _write_atomic(path, data, mode=0o666):
 #     Python 3.13a6 3570 (Add __firstlineno__ class attribute)
 #     Python 3.14a1 3600 (Add LOAD_COMMON_CONSTANT)
 #     Python 3.14a1 3601 (Fix miscompilation of private names in generic classes)
+#     Python 3.14a1 3602 (Update the DEF_* flags values and the SCOPE_OFFSET)
 
 #     Python 3.15 will start with 3700
 
@@ -490,7 +491,7 @@ def _write_atomic(path, data, mode=0o666):
 # Whenever MAGIC_NUMBER is changed, the ranges in the magic_values array
 # in PC/launcher.c must also be updated.
 
-MAGIC_NUMBER = (3601).to_bytes(2, 'little') + b'\r\n'
+MAGIC_NUMBER = (3602).to_bytes(2, 'little') + b'\r\n'
 
 _RAW_MAGIC_NUMBER = int.from_bytes(MAGIC_NUMBER, 'little')  # For import.c
 

Misc/NEWS.d/next/Library/2024-06-07-12-53-52.gh-issue-120029.TbHYTM.rst

@@ -0,0 +1,2 @@
+Remove unused macros in ``symtable.c``.
+Patch by Bénédikt Tran.

Modules/symtablemodule.c

@@ -71,16 +71,17 @@ static int
 symtable_init_constants(PyObject *m)
 {
     if (PyModule_AddIntMacro(m, USE) < 0) return -1;
+    if (PyModule_AddIntMacro(m, DEF_ANNOT) < 0) return -1;
+    if (PyModule_AddIntMacro(m, DEF_IMPORT) < 0) return -1;
     if (PyModule_AddIntMacro(m, DEF_GLOBAL) < 0) return -1;
     if (PyModule_AddIntMacro(m, DEF_NONLOCAL) < 0) return -1;
     if (PyModule_AddIntMacro(m, DEF_LOCAL) < 0) return -1;
     if (PyModule_AddIntMacro(m, DEF_PARAM) < 0) return -1;
     if (PyModule_AddIntMacro(m, DEF_TYPE_PARAM) < 0) return -1;
-    if (PyModule_AddIntMacro(m, DEF_FREE) < 0) return -1;
     if (PyModule_AddIntMacro(m, DEF_FREE_CLASS) < 0) return -1;
-    if (PyModule_AddIntMacro(m, DEF_IMPORT) < 0) return -1;
+    if (PyModule_AddIntMacro(m, DEF_COMP_ITER) < 0) return -1;
+    if (PyModule_AddIntMacro(m, DEF_COMP_CELL) < 0) return -1;
     if (PyModule_AddIntMacro(m, DEF_BOUND) < 0) return -1;
-    if (PyModule_AddIntMacro(m, DEF_ANNOT) < 0) return -1;
 
     if (PyModule_AddIntConstant(m, "TYPE_FUNCTION", FunctionBlock) < 0)
         return -1;

Python/symtable.c

@@ -318,17 +318,16 @@ static void _dump_symtable(PySTEntryObject* ste, PyObject* prefix)
         int scope = _PyST_GetScope(ste, name);
         long flags = _PyST_GetSymbol(ste, name);
         printf("%s  %s: ", PyUnicode_AsUTF8(prefix), PyUnicode_AsUTF8(name));
+        if (flags & USE) printf(" USE");
+        if (flags & DEF_ANNOT) printf(" DEF_ANNOT");
+        if (flags & DEF_IMPORT) printf(" DEF_IMPORT");
         if (flags & DEF_GLOBAL) printf(" DEF_GLOBAL");
+        if (flags & DEF_NONLOCAL) printf(" DEF_NONLOCAL");
         if (flags & DEF_LOCAL) printf(" DEF_LOCAL");
         if (flags & DEF_PARAM) printf(" DEF_PARAM");
-        if (flags & DEF_NONLOCAL) printf(" DEF_NONLOCAL");
-        if (flags & USE) printf(" USE");
-        if (flags & DEF_FREE) printf(" DEF_FREE");
+        if (flags & DEF_TYPE_PARAM) printf(" DEF_TYPE_PARAM");
         if (flags & DEF_FREE_CLASS) printf(" DEF_FREE_CLASS");
-        if (flags & DEF_IMPORT) printf(" DEF_IMPORT");
-        if (flags & DEF_ANNOT) printf(" DEF_ANNOT");
         if (flags & DEF_COMP_ITER) printf(" DEF_COMP_ITER");
-        if (flags & DEF_TYPE_PARAM) printf(" DEF_TYPE_PARAM");
         if (flags & DEF_COMP_CELL) printf(" DEF_COMP_CELL");
         switch (scope) {
             case LOCAL: printf(" LOCAL"); break;
@@ -791,7 +790,6 @@ inline_comprehension(PySTEntryObject *ste, PySTEntryObject *comp,
                 // letting it be marked as free in class scope will break due to
                 // drop_class_free
                 scope = GLOBAL_IMPLICIT;
-                only_flags &= ~DEF_FREE;
                 if (PySet_Discard(comp_free, k) < 0) {
                     return 0;
                 }