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Remove commented code: str+=str is no more super-optimized

This commit is contained in:
Victor Stinner 2011-10-01 01:26:08 +02:00
parent 2219e0a37e
commit bec0fda264
1 changed files with 6 additions and 112 deletions
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118
Python/ceval.c
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@ -136,8 +136,6 @@ static PyObject * import_from(PyObject *, PyObject *);
static int import_all_from(PyObject *, PyObject *);
static void format_exc_check_arg(PyObject *, const char *, PyObject *);
static void format_exc_unbound(PyCodeObject *co, int oparg);
static PyObject * unicode_concatenate(PyObject *, PyObject *,
PyFrameObject *, unsigned char *);
static PyObject * special_lookup(PyObject *, char *, PyObject **);
#define NAME_ERROR_MSG \
@ -1509,17 +1507,11 @@ PyEval_EvalFrameEx(PyFrameObject *f, int throwflag)
TARGET(BINARY_ADD)
w = POP();
v = TOP();
if (PyUnicode_CheckExact(v) &&
PyUnicode_CheckExact(w)) {
x = unicode_concatenate(v, w, f, next_instr);
/* unicode_concatenate consumed the ref to v */
goto skip_decref_vx;
}
else {
if (PyUnicode_Check(v) && PyUnicode_Check(w))
x = PyUnicode_Concat(v, w);
else
x = PyNumber_Add(v, w);
}
Py_DECREF(v);
skip_decref_vx:
Py_DECREF(w);
SET_TOP(x);
if (x != NULL) DISPATCH();
@ -1670,17 +1662,11 @@ PyEval_EvalFrameEx(PyFrameObject *f, int throwflag)
TARGET(INPLACE_ADD)
w = POP();
v = TOP();
if (PyUnicode_CheckExact(v) &&
PyUnicode_CheckExact(w)) {
x = unicode_concatenate(v, w, f, next_instr);
/* unicode_concatenate consumed the ref to v */
goto skip_decref_v;
}
else {
if (PyUnicode_Check(v) && PyUnicode_Check(w))
x = PyUnicode_Concat(v, w);
else
x = PyNumber_InPlaceAdd(v, w);
}
Py_DECREF(v);
skip_decref_v:
Py_DECREF(w);
SET_TOP(x);
if (x != NULL) DISPATCH();
@ -4515,98 +4501,6 @@ format_exc_unbound(PyCodeObject *co, int oparg)
}
}
static PyObject *
unicode_concatenate(PyObject *v, PyObject *w,
PyFrameObject *f, unsigned char *next_instr)
{
/* This function implements 'variable += expr' when both arguments
are (Unicode) strings. */
w = PyUnicode_Concat(v, w);
Py_DECREF(v);
return w;
/* XXX: This optimization is currently disabled as unicode objects in the
new flexible representation are not in-place resizable anymore. */
#if 0
Py_ssize_t v_len = PyUnicode_GET_SIZE(v);
Py_ssize_t w_len = PyUnicode_GET_SIZE(w);
Py_ssize_t new_len = v_len + w_len;
if (new_len < 0) {
PyErr_SetString(PyExc_OverflowError,
"strings are too large to concat");
return NULL;
}
if (Py_REFCNT(v) == 2) {
/* In the common case, there are 2 references to the value
* stored in 'variable' when the += is performed: one on the
* value stack (in 'v') and one still stored in the
* 'variable'. We try to delete the variable now to reduce
* the refcnt to 1.
*/
switch (*next_instr) {
case STORE_FAST:
{
int oparg = PEEKARG();
PyObject **fastlocals = f->f_localsplus;
if (GETLOCAL(oparg) == v)
SETLOCAL(oparg, NULL);
break;
}
case STORE_DEREF:
{
PyObject **freevars = (f->f_localsplus +
f->f_code->co_nlocals);
PyObject *c = freevars[PEEKARG()];
if (PyCell_GET(c) == v)
PyCell_Set(c, NULL);
break;
}
case STORE_NAME:
{
PyObject *names = f->f_code->co_names;
PyObject *name = GETITEM(names, PEEKARG());
PyObject *locals = f->f_locals;
if (PyDict_CheckExact(locals) &&
PyDict_GetItem(locals, name) == v) {
if (PyDict_DelItem(locals, name) != 0) {
PyErr_Clear();
}
}
break;
}
}
}
if (Py_REFCNT(v) == 1 && !PyUnicode_CHECK_INTERNED(v) &&
!PyUnicode_IS_COMPACT((PyUnicodeObject *)v)) {
/* Now we own the last reference to 'v', so we can resize it
* in-place.
*/
if (PyUnicode_Resize(&v, new_len) != 0) {
/* XXX if PyUnicode_Resize() fails, 'v' has been
* deallocated so it cannot be put back into
* 'variable'. The MemoryError is raised when there
* is no value in 'variable', which might (very
* remotely) be a cause of incompatibilities.
*/
return NULL;
}
/* copy 'w' into the newly allocated area of 'v' */
memcpy(PyUnicode_AS_UNICODE(v) + v_len,
PyUnicode_AS_UNICODE(w), w_len*sizeof(Py_UNICODE));
return v;
}
else {
/* When in-place resizing is not an option. */
w = PyUnicode_Concat(v, w);
Py_DECREF(v);
return w;
}
#endif
}
#ifdef DYNAMIC_EXECUTION_PROFILE
static PyObject *