Optimize bytearray % args
Issue #25399: Don't create temporary bytes objects: modify _PyBytes_Format() to
create work directly on bytearray objects.
* Rename _PyBytes_Format() to _PyBytes_FormatEx() just in case if something
outside CPython uses it
* _PyBytes_FormatEx() now uses (char*, Py_ssize_t) for the input string, so
bytearray_format() doesn't need tot create a temporary input bytes object
* Add use_bytearray parameter to _PyBytes_FormatEx() which is passed to
_PyBytesWriter, to create a bytearray buffer instead of a bytes buffer
Most formatting operations are now between 2.5 and 5 times faster.
diff --git a/Objects/bytesobject.c b/Objects/bytesobject.c
index a1f2958..20b11fb 100644
--- a/Objects/bytesobject.c
+++ b/Objects/bytesobject.c
@@ -568,28 +568,32 @@
/* fmt%(v1,v2,...) is roughly equivalent to sprintf(fmt, v1, v2, ...) */
PyObject *
-_PyBytes_Format(PyObject *format, PyObject *args)
+_PyBytes_FormatEx(const char *format, Py_ssize_t format_len,
+ PyObject *args, int use_bytearray)
{
- char *fmt, *res;
+ const char *fmt;
+ char *res;
Py_ssize_t arglen, argidx;
Py_ssize_t fmtcnt;
int args_owned = 0;
PyObject *dict = NULL;
_PyBytesWriter writer;
- if (format == NULL || !PyBytes_Check(format) || args == NULL) {
+ if (args == NULL) {
PyErr_BadInternalCall();
return NULL;
}
- fmt = PyBytes_AS_STRING(format);
- fmtcnt = PyBytes_GET_SIZE(format);
+ fmt = format;
+ fmtcnt = format_len;
_PyBytesWriter_Init(&writer);
+ writer.use_bytearray = use_bytearray;
res = _PyBytesWriter_Alloc(&writer, fmtcnt);
if (res == NULL)
return NULL;
- writer.overallocate = 1;
+ if (!use_bytearray)
+ writer.overallocate = 1;
if (PyTuple_Check(args)) {
arglen = PyTuple_GET_SIZE(args);
@@ -613,10 +617,8 @@
pos = strchr(fmt + 1, '%');
if (pos != NULL)
len = pos - fmt;
- else {
- len = PyBytes_GET_SIZE(format);
- len -= (fmt - PyBytes_AS_STRING(format));
- }
+ else
+ len = format_len - (fmt - format);
assert(len != 0);
Py_MEMCPY(res, fmt, len);
@@ -644,7 +646,7 @@
fmt++;
if (*fmt == '(') {
- char *keystart;
+ const char *keystart;
Py_ssize_t keylen;
PyObject *key;
int pcount = 1;
@@ -924,8 +926,7 @@
"unsupported format character '%c' (0x%x) "
"at index %zd",
c, c,
- (Py_ssize_t)(fmt - 1 -
- PyBytes_AsString(format)));
+ (Py_ssize_t)(fmt - 1 - format));
goto error;
}
@@ -1028,7 +1029,7 @@
/* If overallocation was disabled, ensure that it was the last
write. Otherwise, we missed an optimization */
- assert(writer.overallocate || fmtcnt < 0);
+ assert(writer.overallocate || fmtcnt < 0 || use_bytearray);
} /* until end */
if (argidx < arglen && !dict) {
@@ -3233,11 +3234,15 @@
};
static PyObject *
-bytes_mod(PyObject *v, PyObject *w)
+bytes_mod(PyObject *self, PyObject *args)
{
- if (!PyBytes_Check(v))
- Py_RETURN_NOTIMPLEMENTED;
- return _PyBytes_Format(v, w);
+ if (self == NULL || !PyBytes_Check(self)) {
+ PyErr_BadInternalCall();
+ return NULL;
+ }
+
+ return _PyBytes_FormatEx(PyBytes_AS_STRING(self), PyBytes_GET_SIZE(self),
+ args, 0);
}
static PyNumberMethods bytes_as_number = {