#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
+ 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;
- uint64_t i;
- } dbl_bits = { d };
+static inline uint64_t get_dbits (double d) {
+ union {
+ double dbl;
+ uint64_t i;
+ } dbl_bits = {d};
- return dbl_bits.i;
+ return dbl_bits.i;
}
-static Fp build_fp(double d)
-{
- uint64_t bits = get_dbits(d);
+static Fp build_fp (double d) {
+ uint64_t bits = get_dbits (d);
- Fp fp;
- fp.frac = bits & fracmask;
- fp.exp = (bits & expmask) >> 52;
+ Fp fp;
+ fp.frac = bits & fracmask;
+ fp.exp = (bits & expmask) >> 52u;
- if(fp.exp) {
- fp.frac += hiddenbit;
- fp.exp -= expbias;
+ if (fp.exp) {
+ fp.frac += hiddenbit;
+ fp.exp -= expbias;
- } else {
- fp.exp = -expbias + 1;
- }
+ }
+ else {
+ fp.exp = -expbias + 1;
+ }
- return fp;
+ return fp;
}
-static void normalize(Fp* fp)
-{
- while ((fp->frac & hiddenbit) == 0) {
- fp->frac <<= 1;
- fp->exp--;
- }
+static void normalize (Fp *fp) {
+ while ((fp->frac & hiddenbit) == 0) {
+ fp->frac <<= 1u;
+ fp->exp--;
+ }
- int shift = 64 - 52 - 1;
- fp->frac <<= shift;
- fp->exp -= shift;
+ const unsigned int shift = 64 - 52 - 1;
+ fp->frac <<= shift;
+ fp->exp -= shift;
}
-static void get_normalized_boundaries(Fp* fp, Fp* lower, Fp* upper)
-{
- upper->frac = (fp->frac << 1) + 1;
- upper->exp = fp->exp - 1;
+static void get_normalized_boundaries (Fp *fp, Fp *lower, Fp *upper) {
+ upper->frac = (fp->frac << 1u) + 1u;
+ upper->exp = fp->exp - 1u;
- while ((upper->frac & (hiddenbit << 1)) == 0) {
- upper->frac <<= 1;
- upper->exp--;
- }
+ while ((upper->frac & (hiddenbit << 1u)) == 0) {
+ upper->frac <<= 1u;
+ upper->exp--;
+ }
- int u_shift = 64 - 52 - 2;
+ const unsigned int u_shift = 64 - 52 - 2;
- upper->frac <<= u_shift;
- upper->exp = upper->exp - u_shift;
+ upper->frac <<= u_shift;
+ upper->exp = upper->exp - u_shift;
- int l_shift = fp->frac == hiddenbit ? 2 : 1;
+ unsigned int l_shift = fp->frac == hiddenbit ? 2u : 1u;
- lower->frac = (fp->frac << l_shift) - 1;
- lower->exp = fp->exp - l_shift;
+ lower->frac = (fp->frac << l_shift) - 1;
+ lower->exp = fp->exp - l_shift;
- lower->frac <<= lower->exp - upper->exp;
- lower->exp = upper->exp;
+ lower->frac <<= lower->exp - upper->exp;
+ lower->exp = upper->exp;
}
-static Fp multiply(Fp* a, Fp* b)
-{
- const uint64_t lomask = 0x00000000FFFFFFFF;
+static Fp multiply (Fp *a, Fp *b) {
+ const uint64_t lomask = 0x00000000FFFFFFFFu;
- 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_bl = (a->frac >> 32u) * (b->frac & lomask);
+ uint64_t al_bh = (a->frac & lomask) * (b->frac >> 32u);
+ uint64_t al_bl = (a->frac & lomask) * (b->frac & lomask);
+ uint64_t ah_bh = (a->frac >> 32u) * (b->frac >> 32u);
- uint64_t tmp = (ah_bl & lomask) + (al_bh & lomask) + (al_bl >> 32);
- /* round up */
- tmp += 1U << 31;
+ uint64_t tmp = (ah_bl & lomask) + (al_bh & lomask) + (al_bl >> 32u);
+ /* round up */
+ tmp += 1U << 31u;
- Fp fp = {
- ah_bh + (ah_bl >> 32) + (al_bh >> 32) + (tmp >> 32),
- a->exp + b->exp + 64
- };
+ Fp fp = {
+ ah_bh + (ah_bl >> 32u) + (al_bh >> 32u) + (tmp >> 32u),
+ a->exp + b->exp + 64u
+ };
- return fp;
+ 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;
- }
+ digits[ndigits - 1]--;
+ rem += kappa;
+ }
}
-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;
+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;
+ Fp one;
+ one.frac = 1ULL << -upper->exp;
+ one.exp = upper->exp;
- uint64_t part1 = upper->frac >> -one.exp;
- uint64_t part2 = upper->frac & (one.frac - 1);
+ uint64_t part1 = upper->frac >> -one.exp;
+ uint64_t part2 = upper->frac & (one.frac - 1);
- int idx = 0, kappa = 10;
- uint64_t* divp;
- /* 1000000000 */
- for(divp = tens + 10; kappa > 0; divp++) {
+ int idx = 0, kappa = 10;
+ uint64_t *divp;
+ /* 1000000000 */
+ for (divp = tens + 10; kappa > 0; divp++) {
- uint64_t div = *divp;
- unsigned digit = part1 / div;
+ uint64_t div = *divp;
+ unsigned digit = part1 / div;
- if (digit || idx) {
- digits[idx++] = digit + '0';
- }
+ if (digit || idx) {
+ digits[idx++] = digit + '0';
+ }
- part1 -= digit * div;
- kappa--;
+ part1 -= digit * div;
+ kappa--;
- uint64_t tmp = (part1 <<-one.exp) + part2;
- if (tmp <= delta) {
- *K += kappa;
- round_digit(digits, idx, delta, tmp, div << -one.exp, wfrac);
+ uint64_t tmp = (part1 << -one.exp) + part2;
+ if (tmp <= delta) {
+ *K += kappa;
+ round_digit (digits, idx, delta, tmp, div << -one.exp, wfrac);
- return idx;
- }
- }
+ return idx;
+ }
+ }
- /* 10 */
- uint64_t* unit = tens + 18;
+ /* 10 */
+ uint64_t *unit = tens + 18;
- while(true) {
- part2 *= 10;
- delta *= 10;
- kappa--;
+ while (true) {
+ part2 *= 10;
+ delta *= 10;
+ kappa--;
- unsigned digit = part2 >> -one.exp;
- if (digit || idx) {
- digits[idx++] = digit + '0';
- }
+ unsigned digit = part2 >> -one.exp;
+ if (digit || idx) {
+ digits[idx++] = digit + '0';
+ }
- part2 &= one.frac - 1;
- if (part2 < delta) {
- *K += kappa;
- round_digit(digits, idx, delta, part2, one.frac, wfrac * *unit);
+ part2 &= one.frac - 1;
+ if (part2 < delta) {
+ *K += kappa;
+ round_digit (digits, idx, delta, part2, one.frac, wfrac * *unit);
- return idx;
- }
+ return idx;
+ }
- unit--;
- }
+ unit--;
+ }
}
-static int grisu2(double d, char* digits, int* K)
-{
- Fp w = build_fp(d);
+static int grisu2 (double d, char *digits, int *K) {
+ Fp w = build_fp (d);
- Fp lower, upper;
- get_normalized_boundaries(&w, &lower, &upper);
+ Fp lower, upper;
+ get_normalized_boundaries (&w, &lower, &upper);
- normalize(&w);
+ normalize (&w);
- int k;
- Fp cp = find_cachedpow10(upper.exp, &k);
+ int k;
+ Fp cp = find_cachedpow10 (upper.exp, &k);
- w = multiply(&w, &cp);
- upper = multiply(&upper, &cp);
- lower = multiply(&lower, &cp);
+ w = multiply (&w, &cp);
+ upper = multiply (&upper, &cp);
+ lower = multiply (&lower, &cp);
- lower.frac++;
- upper.frac--;
+ lower.frac++;
+ upper.frac--;
- *K = -k;
+ *K = -k;
- return generate_digits(&w, &upper, &lower, digits, K);
+ return generate_digits (&w, &upper, &lower, digits, K);
}
-static int emit_digits(char* digits, int ndigits, char* dest, int K, bool neg,
- bool scientific)
-{
- int exp = absv(K + ndigits - 1);
-
- /* write plain integer */
- if(K >= 0 && (exp < (ndigits + 7))) {
- memcpy(dest, digits, ndigits);
- memset(dest + ndigits, '0', K);
-
- return ndigits + K;
- }
-
- /* write decimal w/o scientific notation */
- if(!scientific || (K < 0 && (K > -7 || exp < 4))) {
- int offset = ndigits - absv(K);
- /* fp < 1.0 -> write leading zero */
- if(offset <= 0) {
- offset = -offset;
- dest[0] = '0';
- dest[1] = '.';
-
- /* We have up to 21 characters in output available */
- if (offset + ndigits <= 21) {
- memset(dest + 2, '0', offset);
- memcpy(dest + offset + 2, digits, ndigits);
-
- return ndigits + 2 + offset;
- }
- else {
- goto scientific_fallback;
- }
-
- /* fp > 1.0 */
- } else {
- /* Overflow check */
- if (ndigits <= 23) {
- memcpy(dest, digits, offset);
- dest[offset] = '.';
- memcpy(dest + offset + 1, digits + offset, ndigits - offset);
- return ndigits + 1;
- }
-
- goto scientific_fallback;
- }
- }
-
-scientific_fallback:
- /* write decimal w/ scientific notation */
- ndigits = minv(ndigits, 18 - neg);
-
- int idx = 0;
- dest[idx++] = digits[0];
-
- if(ndigits > 1) {
- dest[idx++] = '.';
- memcpy(dest + idx, digits + 1, ndigits - 1);
- idx += ndigits - 1;
- }
-
- dest[idx++] = 'e';
-
- char sign = K + ndigits - 1 < 0 ? '-' : '+';
- dest[idx++] = sign;
-
- int cent = 0;
-
- if(exp > 99) {
- cent = exp / 100;
- dest[idx++] = cent + '0';
- exp -= cent * 100;
- }
- if(exp > 9) {
- int dec = exp / 10;
- dest[idx++] = dec + '0';
- exp -= dec * 10;
-
- } else if(cent) {
- dest[idx++] = '0';
- }
-
- dest[idx++] = exp % 10 + '0';
-
- return idx;
+static int emit_digits (char *digits, int ndigits, char *dest, int K, bool neg,
+ bool scientific) {
+ int exp = absv(K + ndigits - 1);
+
+ /* write plain integer */
+ if (K >= 0 && (exp < (ndigits + 7))) {
+ memcpy(dest, digits, ndigits);
+ memset(dest + ndigits, '0', K);
+
+ return ndigits + K;
+ }
+
+ /* write decimal w/o scientific notation */
+ if (!scientific || (K < 0 && (K > -7 || exp < 4))) {
+ int offset = ndigits - absv(K);
+ /* fp < 1.0 -> write leading zero */
+ if (offset <= 0) {
+ offset = -offset;
+ dest[0] = '0';
+ dest[1] = '.';
+
+ /* We have up to 21 characters in output available */
+ if (offset + ndigits <= 21) {
+ memset(dest + 2, '0', offset);
+ memcpy(dest + offset + 2, digits, ndigits);
+
+ return ndigits + 2 + offset;
+ }
+ else {
+ goto scientific_fallback;
+ }
+
+ /* fp > 1.0 */
+ }
+ else {
+ /* Overflow check */
+ if (ndigits <= 23) {
+ memcpy(dest, digits, offset);
+ dest[offset] = '.';
+ memcpy(dest + offset + 1, digits + offset, ndigits - offset);
+ return ndigits + 1;
+ }
+
+ goto scientific_fallback;
+ }
+ }
+
+ scientific_fallback:
+ /* write decimal w/ scientific notation */
+ ndigits = minv(ndigits, 18 - neg);
+
+ int idx = 0;
+ dest[idx++] = digits[0];
+
+ if (ndigits > 1) {
+ dest[idx++] = '.';
+ memcpy(dest + idx, digits + 1, ndigits - 1);
+ idx += ndigits - 1;
+ }
+
+ dest[idx++] = 'e';
+
+ char sign = K + ndigits - 1 < 0 ? '-' : '+';
+ dest[idx++] = sign;
+
+ int cent = 0;
+
+ if (exp > 99) {
+ cent = exp / 100;
+ dest[idx++] = cent + '0';
+ exp -= cent * 100;
+ }
+ if (exp > 9) {
+ int dec = exp / 10;
+ dest[idx++] = dec + '0';
+ exp -= dec * 10;
+
+ }
+ else if (cent) {
+ dest[idx++] = '0';
+ }
+
+ dest[idx++] = exp % 10 + '0';
+
+ return idx;
}
-static int filter_special(double fp, char* dest)
-{
+static int filter_special (double fp, char *dest) {
int nchars = 3;
- if(fp == 0.0) {
- if(get_dbits(fp) & signmask) {
+ if (fp == 0.0) {
+ if (get_dbits (fp) & signmask) {
dest[0] = '-';
dest[1] = '0';
return 2;
dest[0] = '0';
return 1;
}
- }
+ }
- uint64_t bits = get_dbits(fp);
+ uint64_t bits = get_dbits (fp);
- bool nan = (bits & expmask) == expmask;
+ bool nan = (bits & expmask) == expmask;
- if(!nan) {
- return 0;
- }
+ if (!nan) {
+ return 0;
+ }
- if(bits & fracmask) {
- dest[0] = 'n'; dest[1] = 'a'; dest[2] = 'n';
- } else {
- if(get_dbits(fp) & signmask) {
+ if (bits & fracmask) {
+ dest[0] = 'n';
+ dest[1] = 'a';
+ dest[2] = 'n';
+ }
+ else {
+ if (get_dbits (fp) & signmask) {
dest[0] = '-';
- dest[1] = 'i'; dest[2] = 'n'; dest[3] = 'f';
+ dest[1] = 'i';
+ dest[2] = 'n';
+ dest[3] = 'f';
nchars = 4;
}
else {
- dest[0] = 'i'; dest[1] = 'n'; dest[2] = 'f';
+ dest[0] = 'i';
+ dest[1] = 'n';
+ dest[2] = 'f';
}
- }
+ }
- return nchars;
+ return nchars;
}
-int fpconv_dtoa(double d, char dest[24], bool scientific)
-{
- char digits[18];
+int fpconv_dtoa (double d, char dest[24], bool scientific) {
+ char digits[18];
- int str_len = 0;
- bool neg = false;
+ int str_len = 0;
+ bool neg = false;
- int spec = filter_special(d, dest + str_len);
+ int spec = filter_special (d, dest + str_len);
- if(spec) {
- return str_len + spec;
- }
+ if (spec) {
+ return str_len + spec;
+ }
- if(get_dbits(d) & signmask) {
+ if (get_dbits (d) & signmask) {
dest[0] = '-';
str_len++;
neg = true;
}
- int K = 0;
- int ndigits = grisu2(d, digits, &K);
+ int K = 0;
+ int ndigits = grisu2 (d, digits, &K);
- str_len += emit_digits(digits, ndigits, dest + str_len, K, neg, scientific);
+ str_len += emit_digits (digits, ndigits, dest + str_len, K, neg, scientific);
- return str_len;
+ return str_len;
}