gh-106320: Remove private _PyLong_IsCompact() function

Move the private _PyLong_IsCompact() and _PyLong_CompactValue()
functions to the internal C API (pycore_long.h). Public
PyUnstable_Long_IsCompact() and PyUnstable_Long_CompactValue()
functions can be used instead.

Remove "const" qualifier from PyUnstable_Long_IsCompact() and
PyUnstable_Long_CompactValue() parameter type.

Author: vstinner

Doc/c-api/long.rst

@@ -332,7 +332,7 @@ distinguished from a number.  Use :c:func:`PyErr_Occurred` to disambiguate.
    Returns ``NULL`` on error.  Use :c:func:`PyErr_Occurred` to disambiguate.
 
 
-.. c:function:: int PyUnstable_Long_IsCompact(const PyLongObject* op)
+.. c:function:: int PyUnstable_Long_IsCompact(PyLongObject* op)
 
    Return 1 if *op* is compact, 0 otherwise.
 
@@ -347,7 +347,7 @@ distinguished from a number.  Use :c:func:`PyErr_Occurred` to disambiguate.
    Exactly what values are considered compact is an implementation detail
    and is subject to change.
 
-.. c:function:: Py_ssize_t PyUnstable_Long_CompactValue(const PyLongObject* op)
+.. c:function:: Py_ssize_t PyUnstable_Long_CompactValue(PyLongObject* op)
 
    If *op* is compact, as determined by :c:func:`PyUnstable_Long_IsCompact`,
    return its value.

Include/cpython/longintrepr.h

@@ -89,34 +89,6 @@ struct _longobject {
     _PyLongValue long_value;
 };
 
-
-/* Inline some internals for speed. These should be in pycore_long.h
- * if user code didn't need them inlined. */
-
-#define _PyLong_SIGN_MASK 3
-#define _PyLong_NON_SIZE_BITS 3
-
-
-static inline int
-_PyLong_IsCompact(const PyLongObject* op) {
-    assert(PyType_HasFeature((op)->ob_base.ob_type, Py_TPFLAGS_LONG_SUBCLASS));
-    return op->long_value.lv_tag < (2 << _PyLong_NON_SIZE_BITS);
-}
-
-#define PyUnstable_Long_IsCompact _PyLong_IsCompact
-
-static inline Py_ssize_t
-_PyLong_CompactValue(const PyLongObject *op)
-{
-    assert(PyType_HasFeature((op)->ob_base.ob_type, Py_TPFLAGS_LONG_SUBCLASS));
-    assert(PyUnstable_Long_IsCompact(op));
-    Py_ssize_t sign = 1 - (op->long_value.lv_tag & _PyLong_SIGN_MASK);
-    return sign * (Py_ssize_t)op->long_value.ob_digit[0];
-}
-
-#define PyUnstable_Long_CompactValue _PyLong_CompactValue
-
-
 #ifdef __cplusplus
 }
 #endif

Include/cpython/longobject.h

@@ -4,6 +4,5 @@
 
 PyAPI_FUNC(PyObject*) PyLong_FromUnicodeObject(PyObject *u, int base);
 
-PyAPI_FUNC(int) PyUnstable_Long_IsCompact(const PyLongObject* op);
-PyAPI_FUNC(Py_ssize_t) PyUnstable_Long_CompactValue(const PyLongObject* op);
-
+PyAPI_FUNC(int) PyUnstable_Long_IsCompact(PyLongObject* op);
+PyAPI_FUNC(Py_ssize_t) PyUnstable_Long_CompactValue(PyLongObject* op);

Include/internal/pycore_long.h

@@ -231,37 +231,45 @@ PyAPI_FUNC(int) _PyLong_UnsignedLongLong_Converter(PyObject *, void *);
 // Export for '_testclinic' shared extension (Argument Clinic code)
 PyAPI_FUNC(int) _PyLong_Size_t_Converter(PyObject *, void *);
 
+#define _PyLong_SIGN_MASK 3
+#define _PyLong_NON_SIZE_BITS 3
+
 /* Long value tag bits:
  * 0-1: Sign bits value = (1-sign), ie. negative=2, positive=0, zero=1.
  * 2: Reserved for immortality bit
  * 3+ Unsigned digit count
  */
-#define SIGN_MASK 3
+#define SIGN_MASK _PyLong_SIGN_MASK
 #define SIGN_ZERO 1
 #define SIGN_NEGATIVE 2
-#define NON_SIZE_BITS 3
+#define NON_SIZE_BITS _PyLong_NON_SIZE_BITS
 
-/* The functions _PyLong_IsCompact and _PyLong_CompactValue are defined
- * in Include/cpython/longobject.h, since they need to be inline.
- *
- * "Compact" values have at least one bit to spare,
+/* "Compact" values have at least one bit to spare,
  * so that addition and subtraction can be performed on the values
  * without risk of overflow.
- *
- * The inline functions need tag bits.
- * For readability, rather than do `#define SIGN_MASK _PyLong_SIGN_MASK`
- * we define them to the numbers in both places and then assert that
- * they're the same.
  */
-static_assert(SIGN_MASK == _PyLong_SIGN_MASK, "SIGN_MASK does not match _PyLong_SIGN_MASK");
-static_assert(NON_SIZE_BITS == _PyLong_NON_SIZE_BITS, "NON_SIZE_BITS does not match _PyLong_NON_SIZE_BITS");
 
 /* All *compact" values are guaranteed to fit into
  * a Py_ssize_t with at least one bit to spare.
  * In other words, for 64 bit machines, compact
  * will be signed 63 (or fewer) bit values
  */
 
+static inline int
+_PyLong_IsCompact(const PyLongObject* op) {
+    assert(PyType_HasFeature((op)->ob_base.ob_type, Py_TPFLAGS_LONG_SUBCLASS));
+    return op->long_value.lv_tag < (2 << _PyLong_NON_SIZE_BITS);
+}
+
+static inline Py_ssize_t
+_PyLong_CompactValue(const PyLongObject *op)
+{
+    assert(PyType_HasFeature((op)->ob_base.ob_type, Py_TPFLAGS_LONG_SUBCLASS));
+    assert(_PyLong_IsCompact(op));
+    Py_ssize_t sign = 1 - (op->long_value.lv_tag & _PyLong_SIGN_MASK);
+    return sign * (Py_ssize_t)op->long_value.ob_digit[0];
+}
+
 /* Return 1 if the argument is compact int */
 static inline int
 _PyLong_IsNonNegativeCompact(const PyLongObject* op) {

Objects/longobject.c

@@ -6369,16 +6369,13 @@ _PyLong_FiniTypes(PyInterpreterState *interp)
     _PyStructSequence_FiniBuiltin(interp, &Int_InfoType);
 }
 
-#undef PyUnstable_Long_IsCompact
 
 int
-PyUnstable_Long_IsCompact(const PyLongObject* op) {
+PyUnstable_Long_IsCompact(PyLongObject* op) {
     return _PyLong_IsCompact(op);
 }
 
-#undef PyUnstable_Long_CompactValue
-
 Py_ssize_t
-PyUnstable_Long_CompactValue(const PyLongObject* op) {
+PyUnstable_Long_CompactValue(PyLongObject* op) {
     return _PyLong_CompactValue(op);
 }