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Remove the CACHE_HASH and INTERN_STRINGS preprocessor symbols.

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Tim Peters 2002-03-29 03:29:08 +00:00
parent 835840560b
commit 1f7df3595a
6 changed files with 19 additions and 102 deletions
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30
Include/stringobject.h
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@ -24,28 +24,18 @@ variant that assumes a zero-terminated string. Note that none of the
functions should be applied to nil objects.
*/
/* Two speedup hacks. Caching the hash saves recalculation of a
string's hash value. Interning strings (which requires hash
caching) tries to ensure that only one string object with a given
value exists, so equality tests are one pointer comparison.
Together, these can speed the interpreter up by as much as 20%.
Each costs the size of a long or pointer per string object. In
addition, interned strings live until the end of times. If you are
concerned about memory footprint, simply comment the #define out
here (and rebuild everything!). */
#define CACHE_HASH
#ifdef CACHE_HASH
#define INTERN_STRINGS
#endif
/* Caching the hash (ob_shash) saves recalculation of a string's hash value.
Interning strings (ob_sinterned) tries to ensure that only one string
object with a given value exists, so equality tests can be one pointer
comparison. This is generally restricted to strings that "look like"
Python identifiers, although the intern() builtin can be used to force
interning of any string.
Together, these sped the interpreter by up to 20%. */
typedef struct {
PyObject_VAR_HEAD
#ifdef CACHE_HASH
long ob_shash;
#endif
#ifdef INTERN_STRINGS
PyObject *ob_sinterned;
#endif
char ob_sval[1];
} PyStringObject;
@ -70,15 +60,9 @@ extern DL_IMPORT(PyObject *) PyString_Format(PyObject *, PyObject *);
extern DL_IMPORT(PyObject *) _PyString_FormatLong(PyObject*, int, int,
int, char**, int*);
#ifdef INTERN_STRINGS
extern DL_IMPORT(void) PyString_InternInPlace(PyObject **);
extern DL_IMPORT(PyObject *) PyString_InternFromString(const char *);
extern DL_IMPORT(void) _Py_ReleaseInternedStrings(void);
#else
#define PyString_InternInPlace(p)
#define PyString_InternFromString(cp) PyString_FromString(cp)
#define _Py_ReleaseInternedStrings()
#endif
/* Macro, trading safety for speed */
#define PyString_AS_STRING(op) (((PyStringObject *)(op))->ob_sval)