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-rw-r--r--Objects/longobject.c224
1 files changed, 191 insertions, 33 deletions
diff --git a/Objects/longobject.c b/Objects/longobject.c
index cd04e36..d49594d 100644
--- a/Objects/longobject.c
+++ b/Objects/longobject.c
@@ -1582,10 +1582,12 @@ divrem1(PyLongObject *a, digit n, digit *prem)
static int
long_to_decimal_string_internal(PyObject *aa,
PyObject **p_output,
- _PyUnicodeWriter *writer)
+ _PyUnicodeWriter *writer,
+ _PyBytesWriter *bytes_writer,
+ char **bytes_str)
{
PyLongObject *scratch, *a;
- PyObject *str;
+ PyObject *str = NULL;
Py_ssize_t size, strlen, size_a, i, j;
digit *pout, *pin, rem, tenpow;
int negative;
@@ -1662,7 +1664,13 @@ long_to_decimal_string_internal(PyObject *aa,
return -1;
}
kind = writer->kind;
- str = NULL;
+ }
+ else if (bytes_writer) {
+ *bytes_str = _PyBytesWriter_Prepare(bytes_writer, *bytes_str, strlen);
+ if (*bytes_str == NULL) {
+ Py_DECREF(scratch);
+ return -1;
+ }
}
else {
str = PyUnicode_New(strlen, '9');
@@ -1673,13 +1681,8 @@ long_to_decimal_string_internal(PyObject *aa,
kind = PyUnicode_KIND(str);
}
-#define WRITE_DIGITS(TYPE) \
+#define WRITE_DIGITS(p) \
do { \
- if (writer) \
- p = (TYPE*)PyUnicode_DATA(writer->buffer) + writer->pos + strlen; \
- else \
- p = (TYPE*)PyUnicode_DATA(str) + strlen; \
- \
/* pout[0] through pout[size-2] contribute exactly \
_PyLong_DECIMAL_SHIFT digits each */ \
for (i=0; i < size - 1; i++) { \
@@ -1699,6 +1702,16 @@ long_to_decimal_string_internal(PyObject *aa,
/* and sign */ \
if (negative) \
*--p = '-'; \
+ } while (0)
+
+#define WRITE_UNICODE_DIGITS(TYPE) \
+ do { \
+ if (writer) \
+ p = (TYPE*)PyUnicode_DATA(writer->buffer) + writer->pos + strlen; \
+ else \
+ p = (TYPE*)PyUnicode_DATA(str) + strlen; \
+ \
+ WRITE_DIGITS(p); \
\
/* check we've counted correctly */ \
if (writer) \
@@ -1708,25 +1721,34 @@ long_to_decimal_string_internal(PyObject *aa,
} while (0)
/* fill the string right-to-left */
- if (kind == PyUnicode_1BYTE_KIND) {
+ if (bytes_writer) {
+ char *p = *bytes_str + strlen;
+ WRITE_DIGITS(p);
+ assert(p == *bytes_str);
+ }
+ else if (kind == PyUnicode_1BYTE_KIND) {
Py_UCS1 *p;
- WRITE_DIGITS(Py_UCS1);
+ WRITE_UNICODE_DIGITS(Py_UCS1);
}
else if (kind == PyUnicode_2BYTE_KIND) {
Py_UCS2 *p;
- WRITE_DIGITS(Py_UCS2);
+ WRITE_UNICODE_DIGITS(Py_UCS2);
}
else {
Py_UCS4 *p;
assert (kind == PyUnicode_4BYTE_KIND);
- WRITE_DIGITS(Py_UCS4);
+ WRITE_UNICODE_DIGITS(Py_UCS4);
}
#undef WRITE_DIGITS
+#undef WRITE_UNICODE_DIGITS
Py_DECREF(scratch);
if (writer) {
writer->pos += strlen;
}
+ else if (bytes_writer) {
+ (*bytes_str) += strlen;
+ }
else {
assert(_PyUnicode_CheckConsistency(str, 1));
*p_output = (PyObject *)str;
@@ -1738,7 +1760,7 @@ static PyObject *
long_to_decimal_string(PyObject *aa)
{
PyObject *v;
- if (long_to_decimal_string_internal(aa, &v, NULL) == -1)
+ if (long_to_decimal_string_internal(aa, &v, NULL, NULL, NULL) == -1)
return NULL;
return v;
}
@@ -1750,10 +1772,11 @@ long_to_decimal_string(PyObject *aa)
static int
long_format_binary(PyObject *aa, int base, int alternate,
- PyObject **p_output, _PyUnicodeWriter *writer)
+ PyObject **p_output, _PyUnicodeWriter *writer,
+ _PyBytesWriter *bytes_writer, char **bytes_str)
{
PyLongObject *a = (PyLongObject *)aa;
- PyObject *v;
+ PyObject *v = NULL;
Py_ssize_t sz;
Py_ssize_t size_a;
enum PyUnicode_Kind kind;
@@ -1810,7 +1833,11 @@ long_format_binary(PyObject *aa, int base, int alternate,
if (_PyUnicodeWriter_Prepare(writer, sz, 'x') == -1)
return -1;
kind = writer->kind;
- v = NULL;
+ }
+ else if (bytes_writer) {
+ *bytes_str = _PyBytesWriter_Prepare(bytes_writer, *bytes_str, sz);
+ if (*bytes_str == NULL)
+ return -1;
}
else {
v = PyUnicode_New(sz, 'x');
@@ -1819,13 +1846,8 @@ long_format_binary(PyObject *aa, int base, int alternate,
kind = PyUnicode_KIND(v);
}
-#define WRITE_DIGITS(TYPE) \
+#define WRITE_DIGITS(p) \
do { \
- if (writer) \
- p = (TYPE*)PyUnicode_DATA(writer->buffer) + writer->pos + sz; \
- else \
- p = (TYPE*)PyUnicode_DATA(v) + sz; \
- \
if (size_a == 0) { \
*--p = '0'; \
} \
@@ -1860,30 +1882,50 @@ long_format_binary(PyObject *aa, int base, int alternate,
} \
if (negative) \
*--p = '-'; \
+ } while (0)
+
+#define WRITE_UNICODE_DIGITS(TYPE) \
+ do { \
+ if (writer) \
+ p = (TYPE*)PyUnicode_DATA(writer->buffer) + writer->pos + sz; \
+ else \
+ p = (TYPE*)PyUnicode_DATA(v) + sz; \
+ \
+ WRITE_DIGITS(p); \
+ \
if (writer) \
assert(p == ((TYPE*)PyUnicode_DATA(writer->buffer) + writer->pos)); \
else \
assert(p == (TYPE*)PyUnicode_DATA(v)); \
} while (0)
- if (kind == PyUnicode_1BYTE_KIND) {
+ if (bytes_writer) {
+ char *p = *bytes_str + sz;
+ WRITE_DIGITS(p);
+ assert(p == *bytes_str);
+ }
+ else if (kind == PyUnicode_1BYTE_KIND) {
Py_UCS1 *p;
- WRITE_DIGITS(Py_UCS1);
+ WRITE_UNICODE_DIGITS(Py_UCS1);
}
else if (kind == PyUnicode_2BYTE_KIND) {
Py_UCS2 *p;
- WRITE_DIGITS(Py_UCS2);
+ WRITE_UNICODE_DIGITS(Py_UCS2);
}
else {
Py_UCS4 *p;
assert (kind == PyUnicode_4BYTE_KIND);
- WRITE_DIGITS(Py_UCS4);
+ WRITE_UNICODE_DIGITS(Py_UCS4);
}
#undef WRITE_DIGITS
+#undef WRITE_UNICODE_DIGITS
if (writer) {
writer->pos += sz;
}
+ else if (bytes_writer) {
+ (*bytes_str) += sz;
+ }
else {
assert(_PyUnicode_CheckConsistency(v, 1));
*p_output = v;
@@ -1897,9 +1939,9 @@ _PyLong_Format(PyObject *obj, int base)
PyObject *str;
int err;
if (base == 10)
- err = long_to_decimal_string_internal(obj, &str, NULL);
+ err = long_to_decimal_string_internal(obj, &str, NULL, NULL, NULL);
else
- err = long_format_binary(obj, base, 1, &str, NULL);
+ err = long_format_binary(obj, base, 1, &str, NULL, NULL, NULL);
if (err == -1)
return NULL;
return str;
@@ -1911,9 +1953,31 @@ _PyLong_FormatWriter(_PyUnicodeWriter *writer,
int base, int alternate)
{
if (base == 10)
- return long_to_decimal_string_internal(obj, NULL, writer);
+ return long_to_decimal_string_internal(obj, NULL, writer,
+ NULL, NULL);
+ else
+ return long_format_binary(obj, base, alternate, NULL, writer,
+ NULL, NULL);
+}
+
+char*
+_PyLong_FormatBytesWriter(_PyBytesWriter *writer, char *str,
+ PyObject *obj,
+ int base, int alternate)
+{
+ char *str2;
+ int res;
+ str2 = str;
+ if (base == 10)
+ res = long_to_decimal_string_internal(obj, NULL, NULL,
+ writer, &str2);
else
- return long_format_binary(obj, base, alternate, NULL, writer);
+ res = long_format_binary(obj, base, alternate, NULL, NULL,
+ writer, &str2);
+ if (res < 0)
+ return NULL;
+ assert(str2 != NULL);
+ return str2;
}
/* Table of digit values for 8-bit string -> integer conversion.
@@ -2705,6 +2769,13 @@ PyLong_AsDouble(PyObject *v)
PyErr_SetString(PyExc_TypeError, "an integer is required");
return -1.0;
}
+ if (Py_ABS(Py_SIZE(v)) <= 1) {
+ /* Fast path; single digit long (31 bits) will cast safely
+ to double. This improves performance of FP/long operations
+ by 20%.
+ */
+ return (double)MEDIUM_VALUE((PyLongObject *)v);
+ }
x = _PyLong_Frexp((PyLongObject *)v, &exponent);
if ((x == -1.0 && PyErr_Occurred()) || exponent > DBL_MAX_EXP) {
PyErr_SetString(PyExc_OverflowError,
@@ -2951,8 +3022,14 @@ long_add(PyLongObject *a, PyLongObject *b)
if (Py_SIZE(a) < 0) {
if (Py_SIZE(b) < 0) {
z = x_add(a, b);
- if (z != NULL && Py_SIZE(z) != 0)
+ if (z != NULL) {
+ /* x_add received at least one multiple-digit int,
+ and thus z must be a multiple-digit int.
+ That also means z is not an element of
+ small_ints, so negating it in-place is safe. */
+ assert(Py_REFCNT(z) == 1);
Py_SIZE(z) = -(Py_SIZE(z));
+ }
}
else
z = x_sub(b, a);
@@ -2983,8 +3060,10 @@ long_sub(PyLongObject *a, PyLongObject *b)
z = x_sub(a, b);
else
z = x_add(a, b);
- if (z != NULL && Py_SIZE(z) != 0)
+ if (z != NULL) {
+ assert(Py_SIZE(z) == 0 || Py_REFCNT(z) == 1);
Py_SIZE(z) = -(Py_SIZE(z));
+ }
}
else {
if (Py_SIZE(b) < 0)
@@ -3431,6 +3510,52 @@ long_mul(PyLongObject *a, PyLongObject *b)
return (PyObject *)z;
}
+/* Fast modulo division for single-digit longs. */
+static PyObject *
+fast_mod(PyLongObject *a, PyLongObject *b)
+{
+ sdigit left = a->ob_digit[0];
+ sdigit right = b->ob_digit[0];
+ sdigit mod;
+
+ assert(Py_ABS(Py_SIZE(a)) == 1);
+ assert(Py_ABS(Py_SIZE(b)) == 1);
+
+ if (Py_SIZE(a) == Py_SIZE(b)) {
+ /* 'a' and 'b' have the same sign. */
+ mod = left % right;
+ }
+ else {
+ /* Either 'a' or 'b' is negative. */
+ mod = right - 1 - (left - 1) % right;
+ }
+
+ return PyLong_FromLong(mod * (sdigit)Py_SIZE(b));
+}
+
+/* Fast floor division for single-digit longs. */
+static PyObject *
+fast_floor_div(PyLongObject *a, PyLongObject *b)
+{
+ sdigit left = a->ob_digit[0];
+ sdigit right = b->ob_digit[0];
+ sdigit div;
+
+ assert(Py_ABS(Py_SIZE(a)) == 1);
+ assert(Py_ABS(Py_SIZE(b)) == 1);
+
+ if (Py_SIZE(a) == Py_SIZE(b)) {
+ /* 'a' and 'b' have the same sign. */
+ div = left / right;
+ }
+ else {
+ /* Either 'a' or 'b' is negative. */
+ div = -1 - (left - 1) / right;
+ }
+
+ return PyLong_FromLong(div);
+}
+
/* The / and % operators are now defined in terms of divmod().
The expression a mod b has the value a - b*floor(a/b).
The long_divrem function gives the remainder after division of
@@ -3458,6 +3583,30 @@ l_divmod(PyLongObject *v, PyLongObject *w,
{
PyLongObject *div, *mod;
+ if (Py_ABS(Py_SIZE(v)) == 1 && Py_ABS(Py_SIZE(w)) == 1) {
+ /* Fast path for single-digit longs */
+ div = NULL;
+ if (pdiv != NULL) {
+ div = (PyLongObject *)fast_floor_div(v, w);
+ if (div == NULL) {
+ return -1;
+ }
+ }
+ if (pmod != NULL) {
+ mod = (PyLongObject *)fast_mod(v, w);
+ if (mod == NULL) {
+ Py_XDECREF(div);
+ return -1;
+ }
+ *pmod = mod;
+ }
+ if (pdiv != NULL) {
+ /* We only want to set `*pdiv` when `*pmod` is
+ set successfully. */
+ *pdiv = div;
+ }
+ return 0;
+ }
if (long_divrem(v, w, &div, &mod) < 0)
return -1;
if ((Py_SIZE(mod) < 0 && Py_SIZE(w) > 0) ||
@@ -3502,6 +3651,11 @@ long_div(PyObject *a, PyObject *b)
PyLongObject *div;
CHECK_BINOP(a, b);
+
+ if (Py_ABS(Py_SIZE(a)) == 1 && Py_ABS(Py_SIZE(b)) == 1) {
+ return fast_floor_div((PyLongObject*)a, (PyLongObject*)b);
+ }
+
if (l_divmod((PyLongObject*)a, (PyLongObject*)b, &div, NULL) < 0)
div = NULL;
return (PyObject *)div;
@@ -3777,6 +3931,10 @@ long_mod(PyObject *a, PyObject *b)
CHECK_BINOP(a, b);
+ if (Py_ABS(Py_SIZE(a)) == 1 && Py_ABS(Py_SIZE(b)) == 1) {
+ return fast_mod((PyLongObject*)a, (PyLongObject*)b);
+ }
+
if (l_divmod((PyLongObject*)a, (PyLongObject*)b, NULL, &mod) < 0)
mod = NULL;
return (PyObject *)mod;