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-rw-r--r--src/stdlib/fpconv.c114
1 files changed, 56 insertions, 58 deletions
diff --git a/src/stdlib/fpconv.c b/src/stdlib/fpconv.c
index 97699784..8b994cfa 100644
--- a/src/stdlib/fpconv.c
+++ b/src/stdlib/fpconv.c
@@ -6,37 +6,46 @@
#include "fpconv.h"
#include "powers.h"
-#define fracmask 0x000FFFFFFFFFFFFFU
-#define expmask 0x7FF0000000000000U
+#define fracmask 0x000FFFFFFFFFFFFFU
+#define expmask 0x7FF0000000000000U
#define hiddenbit 0x0010000000000000U
-#define signmask 0x8000000000000000U
-#define expbias (1023 + 52)
+#define signmask 0x8000000000000000U
+#define expbias (1023 + 52)
#define absv(n) ((n) < 0 ? -(n) : (n))
#define minv(a, b) ((a) < (b) ? (a) : (b))
-static uint64_t tens[] = {
- 10000000000000000000U, 1000000000000000000U, 100000000000000000U,
- 10000000000000000U, 1000000000000000U, 100000000000000U,
- 10000000000000U, 1000000000000U, 100000000000U,
- 10000000000U, 1000000000U, 100000000U,
- 10000000U, 1000000U, 100000U,
- 10000U, 1000U, 100U,
- 10U, 1U
-};
-
-static inline uint64_t get_dbits(double d)
-{
+static uint64_t tens[] = {10000000000000000000U,
+ 1000000000000000000U,
+ 100000000000000000U,
+ 10000000000000000U,
+ 1000000000000000U,
+ 100000000000000U,
+ 10000000000000U,
+ 1000000000000U,
+ 100000000000U,
+ 10000000000U,
+ 1000000000U,
+ 100000000U,
+ 10000000U,
+ 1000000U,
+ 100000U,
+ 10000U,
+ 1000U,
+ 100U,
+ 10U,
+ 1U};
+
+static inline uint64_t get_dbits(double d) {
union {
- double dbl;
+ double dbl;
uint64_t i;
- } dbl_bits = { d };
+ } dbl_bits = {d};
return dbl_bits.i;
}
-static Fp build_fp(double d)
-{
+static Fp build_fp(double d) {
uint64_t bits = get_dbits(d);
Fp fp;
@@ -54,8 +63,7 @@ static Fp build_fp(double d)
return fp;
}
-static void normalize(Fp* fp)
-{
+static void normalize(Fp *fp) {
while ((fp->frac & hiddenbit) == 0) {
fp->frac <<= 1;
fp->exp--;
@@ -66,10 +74,9 @@ static void normalize(Fp* fp)
fp->exp -= shift;
}
-static void get_normalized_boundaries(Fp* fp, Fp* lower, Fp* upper)
-{
+static void get_normalized_boundaries(Fp *fp, Fp *lower, Fp *upper) {
upper->frac = (fp->frac << 1) + 1;
- upper->exp = fp->exp - 1;
+ upper->exp = fp->exp - 1;
while ((upper->frac & (hiddenbit << 1)) == 0) {
upper->frac <<= 1;
@@ -81,64 +88,55 @@ static void get_normalized_boundaries(Fp* fp, Fp* lower, Fp* upper)
upper->frac <<= u_shift;
upper->exp = upper->exp - u_shift;
-
int l_shift = fp->frac == hiddenbit ? 2 : 1;
lower->frac = (fp->frac << l_shift) - 1;
lower->exp = fp->exp - l_shift;
-
lower->frac <<= lower->exp - upper->exp;
lower->exp = upper->exp;
}
-static Fp multiply(Fp* a, Fp* b)
-{
+static Fp multiply(Fp *a, Fp *b) {
const uint64_t lomask = 0x00000000FFFFFFFF;
- uint64_t ah_bl = (a->frac >> 32) * (b->frac & lomask);
+ uint64_t ah_bl = (a->frac >> 32) * (b->frac & lomask);
uint64_t al_bh = (a->frac & lomask) * (b->frac >> 32);
uint64_t al_bl = (a->frac & lomask) * (b->frac & lomask);
- uint64_t ah_bh = (a->frac >> 32) * (b->frac >> 32);
+ uint64_t ah_bh = (a->frac >> 32) * (b->frac >> 32);
uint64_t tmp = (ah_bl & lomask) + (al_bh & lomask) + (al_bl >> 32);
/* round up */
tmp += 1U << 31;
- Fp fp = {
- ah_bh + (ah_bl >> 32) + (al_bh >> 32) + (tmp >> 32),
- a->exp + b->exp + 64
- };
+ Fp fp = {ah_bh + (ah_bl >> 32) + (al_bh >> 32) + (tmp >> 32), a->exp + b->exp + 64};
return fp;
}
-static void round_digit(char* digits, int ndigits, uint64_t delta, uint64_t rem, uint64_t kappa, uint64_t frac)
-{
- while (rem < frac && delta - rem >= kappa &&
- (rem + kappa < frac || frac - rem > rem + kappa - frac)) {
+static void round_digit(char *digits, int ndigits, uint64_t delta, uint64_t rem, uint64_t kappa, uint64_t frac) {
+ while (rem < frac && delta - rem >= kappa && (rem + kappa < frac || frac - rem > rem + kappa - frac)) {
digits[ndigits - 1]--;
rem += kappa;
}
}
-static int generate_digits(Fp* fp, Fp* upper, Fp* lower, char* digits, int* K)
-{
+static int generate_digits(Fp *fp, Fp *upper, Fp *lower, char *digits, int *K) {
uint64_t wfrac = upper->frac - fp->frac;
uint64_t delta = upper->frac - lower->frac;
Fp one;
one.frac = 1ULL << -upper->exp;
- one.exp = upper->exp;
+ one.exp = upper->exp;
uint64_t part1 = upper->frac >> -one.exp;
uint64_t part2 = upper->frac & (one.frac - 1);
int idx = 0, kappa = 10;
- uint64_t* divp;
+ uint64_t *divp;
/* 1000000000 */
- for(divp = tens + 10; kappa > 0; divp++) {
+ for (divp = tens + 10; kappa > 0; divp++) {
uint64_t div = *divp;
unsigned digit = part1 / div;
@@ -150,7 +148,7 @@ static int generate_digits(Fp* fp, Fp* upper, Fp* lower, char* digits, int* K)
part1 -= digit * div;
kappa--;
- uint64_t tmp = (part1 <<-one.exp) + part2;
+ uint64_t tmp = (part1 << -one.exp) + part2;
if (tmp <= delta) {
*K += kappa;
round_digit(digits, idx, delta, tmp, div << -one.exp, wfrac);
@@ -160,7 +158,7 @@ static int generate_digits(Fp* fp, Fp* upper, Fp* lower, char* digits, int* K)
}
/* 10 */
- uint64_t* unit = tens + 18;
+ uint64_t *unit = tens + 18;
while (true) {
part2 *= 10;
@@ -184,8 +182,7 @@ static int generate_digits(Fp* fp, Fp* upper, Fp* lower, char* digits, int* K)
}
}
-static int grisu2(double d, char* digits, int* K)
-{
+static int grisu2(double d, char *digits, int *K) {
Fp w = build_fp(d);
Fp lower, upper;
@@ -196,7 +193,7 @@ static int grisu2(double d, char* digits, int* K)
int k;
Fp cp = find_cachedpow10(upper.exp, &k);
- w = multiply(&w, &cp);
+ w = multiply(&w, &cp);
upper = multiply(&upper, &cp);
lower = multiply(&lower, &cp);
@@ -208,8 +205,7 @@ static int grisu2(double d, char* digits, int* K)
return generate_digits(&w, &upper, &lower, digits, K);
}
-static int emit_digits(char* digits, int ndigits, char* dest, int K, bool neg)
-{
+static int emit_digits(char *digits, int ndigits, char *dest, int K, bool neg) {
int exp = absv(K + ndigits - 1);
int max_trailing_zeros = 7;
@@ -240,7 +236,7 @@ static int emit_digits(char* digits, int ndigits, char* dest, int K, bool neg)
return ndigits + 2 + offset;
- /* fp > 1.0 */
+ /* fp > 1.0 */
} else {
memcpy(dest, digits, (size_t)offset);
dest[offset] = '.';
@@ -288,8 +284,7 @@ static int emit_digits(char* digits, int ndigits, char* dest, int K, bool neg)
return idx;
}
-static int filter_special(double fp, char* dest)
-{
+static int filter_special(double fp, char *dest) {
if (fp == 0.0) {
dest[0] = '0';
return 1;
@@ -304,17 +299,20 @@ static int filter_special(double fp, char* dest)
}
if (bits & fracmask) {
- dest[0] = 'n'; dest[1] = 'a'; dest[2] = 'n';
+ dest[0] = 'n';
+ dest[1] = 'a';
+ dest[2] = 'n';
} else {
- dest[0] = 'i'; dest[1] = 'n'; dest[2] = 'f';
+ dest[0] = 'i';
+ dest[1] = 'n';
+ dest[2] = 'f';
}
return 3;
}
-int fpconv_dtoa(double d, char dest[24])
-{
+int fpconv_dtoa(double d, char dest[24]) {
char digits[18];
int str_len = 0;
generated by cgit v1.2.3 (git 2.25.1) at 2026-03-01 10:24:49 +0000