py: Fix some bugs in mpz; add mpz_from_ll and mpz_set_from_ll.
A couple of bugs in mpn_shl, and overflow bug in mpz_set_from_int.
diff --git a/py/mpz.c b/py/mpz.c
index d6aeafd..1619873 100644
--- a/py/mpz.c
+++ b/py/mpz.c
@@ -51,6 +51,9 @@
STATIC uint mpn_shl(mpz_dig_t *idig, mpz_dig_t *jdig, uint jlen, uint n) {
uint n_whole = (n + DIG_SIZE - 1) / DIG_SIZE;
uint n_part = n % DIG_SIZE;
+ if (n_part == 0) {
+ n_part = DIG_SIZE;
+ }
// start from the high end of the digit arrays
idig += jlen + n_whole - 1;
@@ -67,7 +70,7 @@
// store remaining bits
*idig = d >> (DIG_SIZE - n_part);
idig -= n_whole - 1;
- memset(idig, 0, n_whole - 1);
+ memset(idig, 0, (n_whole - 1) * sizeof(mpz_dig_t));
// work out length of result
jlen += n_whole;
@@ -412,6 +415,12 @@
return z;
}
+mpz_t *mpz_from_ll(long long val) {
+ mpz_t *z = mpz_zero();
+ mpz_set_from_ll(z, val);
+ return z;
+}
+
mpz_t *mpz_from_str(const char *str, uint len, bool neg, uint base) {
mpz_t *z = mpz_zero();
mpz_set_from_str(z, str, len, neg, base);
@@ -469,17 +478,38 @@
void mpz_set_from_int(mpz_t *z, machine_int_t val) {
mpz_need_dig(z, MPZ_NUM_DIG_FOR_INT);
+ machine_uint_t uval;
if (val < 0) {
z->neg = 1;
- val = -val;
+ uval = -val;
} else {
z->neg = 0;
+ uval = val;
}
z->len = 0;
- while (val > 0) {
- z->dig[z->len++] = val & DIG_MASK;
- val >>= DIG_SIZE;
+ while (uval > 0) {
+ z->dig[z->len++] = uval & DIG_MASK;
+ uval >>= DIG_SIZE;
+ }
+}
+
+void mpz_set_from_ll(mpz_t *z, long long val) {
+ mpz_need_dig(z, MPZ_NUM_DIG_FOR_LL);
+
+ unsigned long long uval;
+ if (val < 0) {
+ z->neg = 1;
+ uval = -val;
+ } else {
+ z->neg = 0;
+ uval = val;
+ }
+
+ z->len = 0;
+ while (uval > 0) {
+ z->dig[z->len++] = uval & DIG_MASK;
+ uval >>= DIG_SIZE;
}
}