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-rw-r--r--erts/emulator/beam/big.c122
1 files changed, 74 insertions, 48 deletions
diff --git a/erts/emulator/beam/big.c b/erts/emulator/beam/big.c
index 7e0be2a2a7..522f50287a 100644
--- a/erts/emulator/beam/big.c
+++ b/erts/emulator/beam/big.c
@@ -429,6 +429,7 @@
static const byte digits_per_sint_lookup[36-1];
static const byte digits_per_small_lookup[36-1];
static const Sint largest_power_of_base_lookup[36-1];
+static const double lg2_lookup[36-1];
static ERTS_INLINE byte get_digits_per_signed_int(Uint base) {
return digits_per_sint_lookup[base-2];
@@ -442,6 +443,10 @@ static ERTS_INLINE Sint get_largest_power_of_base(Uint base) {
return largest_power_of_base_lookup[base-2];
}
+static ERTS_INLINE double lookup_log2(Uint base) {
+ return lg2_lookup[base - 2];
+}
+
/*
** compare two number vectors
*/
@@ -1720,23 +1725,23 @@ double_to_big(double x, Eterm *heap, Uint hsz)
/*
- ** Estimate the number of decimal digits (include sign)
+ ** Estimate the number of digits in given base (include sign)
*/
-int big_decimal_estimate(Wterm x)
+int big_integer_estimate(Wterm x, Uint base)
{
Eterm* xp = big_val(x);
int lg = I_lg(BIG_V(xp), BIG_SIZE(xp));
- int lg10 = ((lg+1)*28/93)+1;
+ int lgBase = ((lg + 1) / lookup_log2(base)) + 1;
- if (BIG_SIGN(xp)) lg10++; /* add sign */
- return lg10+1; /* add null */
+ if (BIG_SIGN(xp)) lgBase++; /* add sign */
+ return lgBase + 1; /* add null */
}
/*
-** Convert a bignum into a string of decimal numbers
+** Convert a bignum into a string of numbers in given base
*/
-
-static Uint write_big(Wterm x, void (*write_func)(void *, char), void *arg)
+static Uint write_big(Wterm x, int base, void (*write_func)(void *, char),
+ void *arg)
{
Eterm* xp = big_val(x);
ErtsDigit* dx = BIG_V(xp);
@@ -1744,48 +1749,72 @@ static Uint write_big(Wterm x, void (*write_func)(void *, char), void *arg)
short sign = BIG_SIGN(xp);
ErtsDigit rem;
Uint n = 0;
- const Uint digits_per_Sint = get_digits_per_signed_int(10);
- const Sint largest_pow_of_base = get_largest_power_of_base(10);
+ const Uint digits_per_Sint = get_digits_per_signed_int(base);
+ const Sint largest_pow_of_base = get_largest_power_of_base(base);
if (xl == 1 && *dx < largest_pow_of_base) {
- rem = *dx;
- if (rem == 0) {
- (*write_func)(arg, '0'); n++;
- } else {
- while(rem) {
- (*write_func)(arg, (rem % 10) + '0'); n++;
- rem /= 10;
- }
- }
+ rem = *dx;
+ if (rem == 0) {
+ (*write_func)(arg, '0'); n++;
+ } else {
+ while(rem) {
+ int digit = rem % base;
+
+ if (digit < 10) {
+ (*write_func)(arg, digit + '0'); n++;
+ } else {
+ (*write_func)(arg, 'A' + (digit - 10)); n++;
+ }
+
+ rem /= base;
+ }
+ }
} else {
- ErtsDigit* tmp = (ErtsDigit*) erts_alloc(ERTS_ALC_T_TMP,
- sizeof(ErtsDigit)*xl);
- dsize_t tmpl = xl;
+ ErtsDigit* tmp = (ErtsDigit*) erts_alloc(ERTS_ALC_T_TMP,
+ sizeof(ErtsDigit) * xl);
+ dsize_t tmpl = xl;
- MOVE_DIGITS(tmp, dx, xl);
+ MOVE_DIGITS(tmp, dx, xl);
- while(1) {
+ while(1) {
tmpl = D_div(tmp, tmpl, largest_pow_of_base, tmp, &rem);
- if (tmpl == 1 && *tmp == 0) {
- while(rem) {
- (*write_func)(arg, (rem % 10)+'0'); n++;
- rem /= 10;
- }
- break;
- } else {
+
+ if (tmpl == 1 && *tmp == 0) {
+ while(rem) {
+ int digit = rem % base;
+
+ if (digit < 10) {
+ (*write_func)(arg, digit + '0'); n++;
+ } else {
+ (*write_func)(arg, 'A' + (digit - 10)); n++;
+ }
+
+ rem /= base;
+ }
+ break;
+ } else {
Uint i = digits_per_Sint;
- while(i--) {
- (*write_func)(arg, (rem % 10)+'0'); n++;
- rem /= 10;
- }
- }
- }
- erts_free(ERTS_ALC_T_TMP, (void *) tmp);
+
+ while(i--) {
+ int digit = rem % base;
+
+ if (digit < 10) {
+ (*write_func)(arg, digit + '0'); n++;
+ } else {
+ (*write_func)(arg, 'A' + (digit - 10)); n++;
+ }
+
+ rem /= base;
+ }
+ }
+ }
+ erts_free(ERTS_ALC_T_TMP, (void *) tmp);
}
if (sign) {
- (*write_func)(arg, '-'); n++;
+ (*write_func)(arg, '-'); n++;
}
+
return n;
}
@@ -1802,12 +1831,12 @@ write_list(void *arg, char c)
blp->hp += 2;
}
-Eterm erts_big_to_list(Eterm x, Eterm **hpp)
+Eterm erts_big_to_list(Eterm x, int base, Eterm **hpp)
{
struct big_list__ bl;
bl.hp = *hpp;
bl.res = NIL;
- write_big(x, write_list, (void *) &bl);
+ write_big(x, base, write_list, (void *) &bl);
*hpp = bl.hp;
return bl.res;
}
@@ -1818,11 +1847,11 @@ write_string(void *arg, char c)
*(--(*((char **) arg))) = c;
}
-char *erts_big_to_string(Wterm x, char *buf, Uint buf_sz)
+char *erts_big_to_string(Wterm x, int base, char *buf, Uint buf_sz)
{
char *big_str = buf + buf_sz - 1;
*big_str = '\0';
- write_big(x, write_string, (void *) &big_str);
+ write_big(x, base, write_string, (void*)&big_str);
ASSERT(buf <= big_str && big_str <= buf + buf_sz - 1);
return big_str;
}
@@ -1831,11 +1860,11 @@ char *erts_big_to_string(Wterm x, char *buf, Uint buf_sz)
* e.g. 1 bsl 64 -> "18446744073709551616"
*/
-Uint erts_big_to_binary_bytes(Eterm x, char *buf, Uint buf_sz)
+Uint erts_big_to_binary_bytes(Eterm x, int base, char *buf, Uint buf_sz)
{
char *big_str = buf + buf_sz;
Uint n;
- n = write_big(x, write_string, (void *) &big_str);
+ n = write_big(x, base, write_string, (void *) &big_str);
ASSERT(buf <= big_str && big_str <= buf + buf_sz);
return n;
}
@@ -2578,9 +2607,6 @@ static const double lg2_lookup[36-1] = {
4.32193, 4.39232, 4.45943, 4.52356, 4.58496, 4.64386, 4.70044, 4.75489,
4.80735, 4.85798, 4.90689, 4.9542, 5.0, 5.04439, 5.08746, 5.12928, 5.16993
};
-static ERTS_INLINE double lookup_log2(Uint base) {
- return lg2_lookup[base - 2];
-}
/*
* How many digits can fit into a signed int (Sint) for given base, we take
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-21 16:35:59 +0000