diff --git a/Include/unicodeobject.h b/Include/unicodeobject.h index 7917c689afe..c0036bf837e 100644 --- a/Include/unicodeobject.h +++ b/Include/unicodeobject.h @@ -352,14 +352,19 @@ typedef PY_UNICODE_TYPE Py_UNICODE; Py_UNICODE_ISDIGIT(ch) || \ Py_UNICODE_ISNUMERIC(ch)) +/* memcpy has a considerable setup overhead on many platforms; use a + loop for short strings (the "16" below is pretty arbitary) */ #define Py_UNICODE_COPY(target, source, length) do\ - {int i; Py_UNICODE *t = (target); const Py_UNICODE *s = (source);\ - for (i = 0; i < (length); i++) t[i] = s[i];\ + {Py_ssize_t i_; Py_UNICODE *t_ = (target); const Py_UNICODE *s_ = (source);\ + if (length > 16)\ + memcpy(t_, s_, (length)*sizeof(Py_UNICODE));\ + else\ + for (i_ = 0; i_ < (length); i_++) t_[i_] = s_[i_];\ } while (0) #define Py_UNICODE_FILL(target, value, length) do\ - {int i; Py_UNICODE *t = (target); Py_UNICODE v = (value);\ - for (i = 0; i < (length); i++) t[i] = v;\ + {Py_ssize_t i_; Py_UNICODE *t_ = (target); Py_UNICODE v_ = (value);\ + for (i_ = 0; i_ < (length); i_++) t_[i_] = v_;\ } while (0) #define Py_UNICODE_MATCH(string, offset, substring)\ diff --git a/Objects/unicodeobject.c b/Objects/unicodeobject.c index 6f04a6db396..85cbed285d7 100644 --- a/Objects/unicodeobject.c +++ b/Objects/unicodeobject.c @@ -5900,11 +5900,18 @@ unicode_repeat(PyUnicodeObject *str, Py_ssize_t len) if (str->length == 1 && len > 0) { Py_UNICODE_FILL(p, str->str[0], len); - } else - while (len-- > 0) { + } else { + int done = 0; /* number of characters copied this far */ + if (done < nchars) { Py_UNICODE_COPY(p, str->str, str->length); - p += str->length; - } + done = str->length; + } + while (done < nchars) { + int n = (done <= nchars-done) ? done : nchars-done; + Py_UNICODE_COPY(p+done, p, n); + done += n; + } + } return (PyObject*) u; }