cosmopolitan/libc/stdio/dtoa.c
Justine Tunney ae5d06dc53 Unbloat build config
- 10.5% reduction of o//depend dependency graph
- 8.8% reduction in latency of make command
- Fix issue with temporary file cleanup

There's a new -w option in compile.com that turns off the recent
Landlock output path workaround for "good commands" which do not
unlink() the output file like GNU tooling does.

Our new GNU Make unveil sandboxing appears to have zero overhead
in the grand scheme of things. Full builds are pretty fast since
the only thing that's actually slowed us down is probably libcxx

    make -j16 MODE=rel
    RL: took 85,732,063µs wall time
    RL: ballooned to 323,612kb in size
    RL: needed 828,560,521µs cpu (11% kernel)
    RL: caused 39,080,670 page faults (99% memcpy)
    RL: 350,073 context switches (72% consensual)
    RL: performed 0 reads and 11,494,960 write i/o operations

pledge() and unveil() no longer consider ENOSYS to be an error.
These functions have also been added to Python's cosmo module.

This change also removes some WIN32 APIs and System Five magnums
which we're not using and it's doubtful anyone else would be too
2022-08-10 04:43:09 -07:00

534 lines
15 KiB
C

/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi│
╞══════════════════════════════════════════════════════════════════════════════╡
│ Copyright (C) 1997, 1999, 2001 Lucent Technologies │
│ All Rights Reserved │
│ │
│ Permission to use, copy, modify, and distribute this software and │
│ its documentation for any purpose and without fee is hereby │
│ granted, provided that the above copyright notice appear in all │
│ copies and that both that the copyright notice and this │
│ permission notice and warranty disclaimer appear in supporting │
│ documentation, and that the name of Lucent or any of its entities │
│ not be used in advertising or publicity pertaining to │
│ distribution of the software without specific, written prior │
│ permission. │
│ │
│ LUCENT DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, │
│ INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. │
│ IN NO EVENT SHALL LUCENT OR ANY OF ITS ENTITIES BE LIABLE FOR ANY │
│ SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES │
│ WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER │
│ IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, │
│ ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF │
│ THIS SOFTWARE. │
╚─────────────────────────────────────────────────────────────────────────────*/
#include "libc/assert.h"
#include "libc/fmt/fmt.h"
#include "libc/fmt/fmt.internal.h"
#include "libc/fmt/internal.h"
#include "libc/macros.internal.h"
#include "libc/nexgen32e/bsr.h"
#include "libc/str/str.h"
#include "third_party/gdtoa/gdtoa.h"
/**
* @fileoverview Floating-Point Formatting
*
* This implements most of ANSI C's printf floating-point directives.
* omitting L, with %.0g and %.0G giving the shortest decimal string
* that rounds to the number being converted, and with negative
* precisions allowed for %f.
*/
struct FPBits {
uint32_t bits[4];
const FPI *fpi;
int sign;
int ex; // exponent
int kind;
};
union U {
double d;
uint64_t q;
long double ld;
unsigned int ui[4];
unsigned short us[5];
};
static const FPI kFpiDbl = {
.nbits = 53,
.emin = 1 - 1023 - 53 + 1,
.emax = 2046 - 1023 - 53 + 1,
.rounding = FPI_Round_near,
.sudden_underflow = 0,
};
static const FPI kFpiLdbl = {
.nbits = 64,
.emin = 1 - 16383 - 64 + 1,
.emax = 32766 - 16383 - 64 + 1,
.rounding = FPI_Round_near,
.sudden_underflow = 0,
};
static const char kSpecialFloats[2][2][4] = {
{"INF", "inf"},
{"NAN", "nan"},
};
static void dfpbits(union U *u, struct FPBits *b) {
int ex, i;
uint32_t *bits;
b->fpi = &kFpiDbl;
b->sign = u->ui[1] & 0x80000000L;
bits = b->bits;
bits[1] = u->ui[1] & 0xfffff;
bits[0] = u->ui[0];
if ((ex = (u->ui[1] & 0x7ff00000L) >> 20) != 0) {
if (ex == 0x7ff) {
// Infinity or NaN
i = bits[0] | bits[1] ? STRTOG_NaN : STRTOG_Infinite;
} else {
i = STRTOG_Normal;
bits[1] |= 0x100000;
}
} else if (bits[0] | bits[1]) {
i = STRTOG_Denormal;
ex = 1;
} else {
i = STRTOG_Zero;
}
b->kind = i;
b->ex = ex - (0x3ff + 52);
}
static void xfpbits(union U *u, struct FPBits *b) {
uint32_t *bits;
int ex, i;
b->fpi = &kFpiLdbl;
b->sign = u->us[4] & 0x8000;
bits = b->bits;
bits[1] = ((unsigned)u->us[3] << 16) | u->us[2];
bits[0] = ((unsigned)u->us[1] << 16) | u->us[0];
if ((ex = u->us[4] & 0x7fff) != 0) {
i = STRTOG_Normal;
if (ex == 0x7fff) // Infinity or NaN
i = bits[0] | bits[1] ? STRTOG_NaN : STRTOG_Infinite;
} else if (bits[0] | bits[1]) {
i = STRTOG_Denormal;
ex = 1;
} else {
i = STRTOG_Zero;
}
b->kind = i;
b->ex = ex - (0x3fff + 63);
}
// returns number of hex digits minus 1, or 0 for zero
static int fpiprec(struct FPBits *b) {
FPI *fpi;
int i, j, k, m;
uint32_t *bits;
if (b->kind == STRTOG_Zero) return (b->ex = 0);
fpi = b->fpi;
bits = b->bits;
for (k = (fpi->nbits - 1) >> 2; k > 0; --k) {
if ((bits[k >> 3] >> 4 * (k & 7)) & 0xf) {
m = k >> 3;
for (i = 0; i <= m; ++i)
if (bits[i]) {
if (i > 0) {
k -= 8 * i;
b->ex += 32 * i;
for (j = i; j <= m; ++j) {
bits[j - i] = bits[j];
}
}
break;
}
for (i = 0; i < 28 && !((bits[0] >> i) & 0xf); i += 4) donothing;
if (i) {
b->ex += i;
m = k >> 3;
k -= (i >> 2);
for (j = 0;; ++j) {
bits[j] >>= i;
if (j == m) break;
bits[j] |= bits[j + 1] << (32 - i);
}
}
break;
}
}
return k;
}
// round to prec hex digits after the "."
// prec1 = incoming precision (after ".")
static int bround(struct FPBits *b, int prec, int prec1) {
uint32_t *bits, t;
int i, inc, j, k, m, n;
m = prec1 - prec;
bits = b->bits;
inc = 0;
k = m - 1;
if ((t = bits[k >> 3] >> (j = (k & 7) * 4)) & 8) {
if (t & 7) goto inc1;
if (j && bits[k >> 3] << (32 - j)) goto inc1;
while (k >= 8) {
k -= 8;
if (bits[k >> 3]) {
inc1:
inc = 1;
goto haveinc;
}
}
}
haveinc:
b->ex += m * 4;
i = m >> 3;
k = prec1 >> 3;
j = i;
if ((n = 4 * (m & 7)))
for (;; ++j) {
bits[j - i] = bits[j] >> n;
if (j == k) break;
bits[j - i] |= bits[j + 1] << (32 - n);
}
else
for (;; ++j) {
bits[j - i] = bits[j];
if (j == k) break;
}
k = prec >> 3;
if (inc) {
for (j = 0; !(++bits[j] & 0xffffffff); ++j) donothing;
if (j > k) {
onebit:
bits[0] = 1;
b->ex += 4 * prec;
return 1;
}
if ((j = prec & 7) < 7 && bits[k] >> (j + 1) * 4) goto onebit;
}
for (i = 0; !(bits[i >> 3] & (0xf << 4 * (i & 7))); ++i) donothing;
if (i) {
b->ex += 4 * i;
prec -= i;
j = i >> 3;
i &= 7;
i *= 4;
for (m = j;; ++m) {
bits[m - j] = bits[m] >> i;
if (m == k) break;
bits[m - j] |= bits[m + 1] << (32 - i);
}
}
return prec;
}
int __fmt_dtoa(int (*out)(const char *, void *, size_t), void *arg, int d,
int flags, int prec, int sign, int width, bool longdouble,
char qchar, unsigned char signbit, const char *alphabet,
va_list va) {
double x;
union U u;
struct FPBits fpb;
char *s, *q, *se, *s0, special[8];
int c, k, i1, ui, bw, bex, sgn, prec1, decpt;
x = 0;
switch (d) {
case 'F':
case 'f':
if (!(flags & FLAGS_PRECISION)) prec = 6;
if (!longdouble) {
x = va_arg(va, double);
s = s0 = dtoa(x, 3, prec, &decpt, &fpb.sign, &se);
if (decpt == 9999) {
if (s && s[0] == 'N') {
fpb.kind = STRTOG_NaN;
} else {
fpb.kind = STRTOG_Infinite;
}
}
} else {
u.ld = va_arg(va, long double);
xfpbits(&u, &fpb);
s = s0 =
gdtoa(fpb.fpi, fpb.ex, fpb.bits, &fpb.kind, 3, prec, &decpt, &se);
}
if (decpt == 9999) {
Format9999:
if (s0) freedtoa(s0);
bzero(special, sizeof(special));
s = q = special;
if (fpb.sign) {
*q++ = '-';
} else if (flags & FLAGS_PLUS) {
*q++ = '+';
} else if (flags & FLAGS_SPACE) {
*q++ = ' ';
}
memcpy(q, kSpecialFloats[fpb.kind == STRTOG_NaN][d >= 'a'], 4);
flags &= ~(FLAGS_PRECISION | FLAGS_PLUS | FLAGS_HASH | FLAGS_SPACE);
prec = 0;
return __fmt_stoa(out, arg, s, flags, prec, width, signbit, qchar);
}
FormatReal:
if (fpb.sign /* && (x || sign) */) sign = '-';
if (prec > 0) width -= prec;
if (width > 0) {
if (sign) --width;
if (decpt <= 0) {
--width;
if (prec > 0) --width;
} else {
if (s == se) decpt = 1;
width -= decpt;
if (prec > 0 || (flags & FLAGS_HASH)) --width;
}
}
if (width > 0 && !(flags & FLAGS_LEFT)) {
if ((flags & FLAGS_ZEROPAD)) {
if (sign) __FMT_PUT(sign);
sign = 0;
do __FMT_PUT('0');
while (--width > 0);
} else
do __FMT_PUT(' ');
while (--width > 0);
}
if (sign) __FMT_PUT(sign);
if (decpt <= 0) {
__FMT_PUT('0');
if (prec > 0 || (flags & FLAGS_HASH)) __FMT_PUT('.');
while (decpt < 0) {
__FMT_PUT('0');
prec--;
decpt++;
}
} else {
do {
if ((c = *s)) {
s++;
} else {
c = '0';
}
__FMT_PUT(c);
} while (--decpt > 0);
if (prec > 0 || (flags & FLAGS_HASH)) __FMT_PUT('.');
}
while (--prec >= 0) {
if ((c = *s)) {
s++;
} else {
c = '0';
}
__FMT_PUT(c);
}
while (--width >= 0) __FMT_PUT(' ');
if (s0) freedtoa(s0);
break;
case 'G':
case 'g':
if (!(flags & FLAGS_PRECISION)) prec = 6;
if (prec < 0) prec = 0;
if (!longdouble) {
x = va_arg(va, double);
s = s0 = dtoa(x, prec ? 2 : 0, prec, &decpt, &fpb.sign, &se);
if (decpt == 9999) {
if (s && s[0] == 'N') {
fpb.kind = STRTOG_NaN;
} else {
fpb.kind = STRTOG_Infinite;
}
}
} else {
u.ld = va_arg(va, long double);
xfpbits(&u, &fpb);
s = s0 = gdtoa(fpb.fpi, fpb.ex, fpb.bits, &fpb.kind, prec ? 2 : 0, prec,
&decpt, &se);
}
if (decpt == 9999) goto Format9999;
c = se - s;
prec1 = prec;
if (!prec) {
prec = c;
prec1 = c + (s[1] || (flags & FLAGS_HASH) ? 5 : 4);
// %.0g gives 10 rather than 1e1
}
if (decpt > -4 && decpt <= prec1) {
if ((flags & FLAGS_HASH))
prec -= decpt;
else
prec = c - decpt;
if (prec < 0) prec = 0;
goto FormatReal;
}
d -= 2;
if (!(flags & FLAGS_HASH) && prec > c) prec = c;
--prec;
goto FormatExpo;
case 'e':
case 'E':
if (!(flags & FLAGS_PRECISION)) prec = 6;
if (prec < 0) prec = 0;
if (!longdouble) {
x = va_arg(va, double);
s = s0 = dtoa(x, prec ? 2 : 0, prec + 1, &decpt, &fpb.sign, &se);
if (decpt == 9999) {
if (s && s[0] == 'N') {
fpb.kind = STRTOG_NaN;
} else {
fpb.kind = STRTOG_Infinite;
}
}
} else {
u.ld = va_arg(va, long double);
xfpbits(&u, &fpb);
s = s0 = gdtoa(fpb.fpi, fpb.ex, fpb.bits, &fpb.kind, prec ? 2 : 0, prec,
&decpt, &se);
}
if (decpt == 9999) goto Format9999;
FormatExpo:
if (fpb.sign /* && (x || sign) */) sign = '-';
if ((width -= prec + 5) > 0) {
if (sign) --width;
if (prec || (flags & FLAGS_HASH)) --width;
}
if ((c = --decpt) < 0) c = -c;
while (c >= 100) {
--width;
c /= 10;
}
if (width > 0 && !(flags & FLAGS_LEFT)) {
if ((flags & FLAGS_ZEROPAD)) {
if (sign) __FMT_PUT(sign);
sign = 0;
do __FMT_PUT('0');
while (--width > 0);
} else
do __FMT_PUT(' ');
while (--width > 0);
}
if (sign) __FMT_PUT(sign);
__FMT_PUT(*s++);
if (prec || (flags & FLAGS_HASH)) __FMT_PUT('.');
while (--prec >= 0) {
if ((c = *s))
s++;
else
c = '0';
__FMT_PUT(c);
}
__FMT_PUT(d);
if (decpt < 0) {
__FMT_PUT('-');
decpt = -decpt;
} else
__FMT_PUT('+');
for (c = 2, k = 10; 10 * k <= decpt; c++, k *= 10) donothing;
for (;;) {
i1 = decpt / k;
__FMT_PUT(i1 + '0');
if (--c <= 0) break;
decpt -= i1 * k;
decpt *= 10;
}
while (--width >= 0) __FMT_PUT(' ');
freedtoa(s0);
break;
case 'A':
alphabet = "0123456789ABCDEFPX";
goto FormatBinary;
case 'a':
alphabet = "0123456789abcdefpx";
FormatBinary:
if (longdouble) {
u.ld = va_arg(va, long double);
xfpbits(&u, &fpb);
} else {
u.d = va_arg(va, double);
dfpbits(&u, &fpb);
}
if (fpb.kind == STRTOG_Infinite || fpb.kind == STRTOG_NaN) {
s0 = 0;
goto Format9999;
}
prec1 = fpiprec(&fpb);
if ((flags & FLAGS_PRECISION) && prec < prec1) {
prec1 = bround(&fpb, prec, prec1);
}
bw = 1;
bex = fpb.ex + 4 * prec1;
if (bex) {
if ((i1 = bex) < 0) i1 = -i1;
while (i1 >= 10) {
++bw;
i1 /= 10;
}
}
if (fpb.sign /* && (sign || fpb.kind != STRTOG_Zero) */) {
sign = '-';
}
if ((width -= bw + 5) > 0) {
if (sign) --width;
if (prec1 || (flags & FLAGS_HASH)) --width;
}
if ((width -= prec1) > 0 && !(flags & FLAGS_LEFT) &&
!(flags & FLAGS_ZEROPAD)) {
do __FMT_PUT(' ');
while (--width > 0);
}
if (sign) __FMT_PUT(sign);
__FMT_PUT('0');
__FMT_PUT(alphabet[17]);
if ((flags & FLAGS_ZEROPAD) && width > 0 && !(flags & FLAGS_LEFT)) {
do __FMT_PUT('0');
while (--width > 0);
}
i1 = prec1 & 7;
k = prec1 >> 3;
__FMT_PUT(alphabet[(fpb.bits[k] >> 4 * i1) & 0xf]);
if (prec1 > 0 || (flags & FLAGS_HASH)) __FMT_PUT('.');
if (prec1 > 0) {
prec -= prec1;
while (prec1 > 0) {
if (--i1 < 0) {
if (--k < 0) break;
i1 = 7;
}
__FMT_PUT(alphabet[(fpb.bits[k] >> 4 * i1) & 0xf]);
--prec1;
}
if ((flags & FLAGS_HASH) && prec > 0) {
do __FMT_PUT(0);
while (--prec > 0);
}
}
__FMT_PUT(alphabet[16]);
if (bex < 0) {
__FMT_PUT('-');
bex = -bex;
} else
__FMT_PUT('+');
for (c = 1; 10 * c <= bex; c *= 10) donothing;
for (;;) {
i1 = bex / c;
__FMT_PUT('0' + i1);
if (!--bw) break;
bex -= i1 * c;
bex *= 10;
}
while (--width >= 0) __FMT_PUT(' ');
break;
default:
unreachable;
}
return 0;
}