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libc/printf: Remove vestigial "full" parameter to _to_float()

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The _to_float routine was apparently written to be able to take a 32
bit float bit representationa as well as a 64 bit double.  But in a
printf routine, that can never happen per the C standard (where floats
are always promoted to doubles in varargs context).

This was just hard-configured to 1 at the top of the file, and nothing
else in the project sets "DOUBLE" to try to change it.  Just remove
it.  If we ever want code to convert a float to a double in memory so
we can use this routine, we have it in libgcc.  Or even in hardware on
the FPU where available.

Change-Id: I796814c0fce3ce96faa34fde8da411a28c826699
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
This commit is contained in:
Andy Ross 2016-08-15 11:37:14 -07:00 committed by Anas Nashif
parent a4537cb0d3
commit 073cfddd0f
1 changed files with 14 additions and 37 deletions
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51
lib/libc/minimal/source/stdout/prf.c
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@ -31,10 +31,6 @@
#define EOF -1
#endif
#ifndef DOUBLE
#define DOUBLE 1
#endif
static void _uc(char *buf)
{
for (/**/; *buf; buf++) {
@ -263,7 +259,6 @@ static char _get_digit(uint32_t fract[], int *digit_count)
* Parameters:
* "buf" Buffer to write result into.
* "double_temp" # to convert (either IEEE single or double).
* "full" TRUE if IEEE double, else IEEE single.
* "c" The conversion type (one of e,E,f,g,G).
* "falt" TRUE if "#" conversion flag in effect.
* "fplus" TRUE if "+" conversion flag in effect.
@ -281,7 +276,7 @@ static char _get_digit(uint32_t fract[], int *digit_count)
#define MAXFP1 0xFFFFFFFF /* Largest # if first fp format */
#define MAXFP2 0x0FFFFFFF /* Largest # in second fp format */
static int _to_float(char *buf, uint32_t double_temp[], int full, int c,
static int _to_float(char *buf, uint32_t double_temp[], int c,
int falt, int fplus, int fspace, int precision)
{
register int decexp;
@ -292,22 +287,14 @@ static int _to_float(char *buf, uint32_t double_temp[], int full, int c,
int prune_zero;
char *start = buf;
if (full) { /* IEEE double */
exp = (double_temp[1] >> 20) & 0x7FF;
fract[1] = (double_temp[1] << 11) & 0x7FFFF800;
fract[1] |= ((double_temp[0] >> 21) & 0x000007FF);
fract[0] = double_temp[0] << 11;
} else {
/* IEEE float */
exp = (double_temp[0] >> 23) & 0xFF;
fract[1] = (double_temp[0] << 8) & 0x7FFFFF00;
fract[0] = 0;
}
exp = (double_temp[1] >> 20) & 0x7FF;
fract[1] = (double_temp[1] << 11) & 0x7FFFF800;
fract[1] |= ((double_temp[0] >> 21) & 0x000007FF);
fract[0] = double_temp[0] << 11;
if ((full && (exp == 0x7FF)) || ((!full) && (exp == 0xFF))) {
if (exp == 0x7FF) {
if ((fract[1] | fract[0]) == 0) {
if ((full && (double_temp[1] & 0x80000000))
|| (!full && (double_temp[0] & 0x80000000))) {
if ((double_temp[1] & 0x80000000)) {
*buf++ = '-';
*buf++ = 'I';
*buf++ = 'N';
@ -328,17 +315,13 @@ static int _to_float(char *buf, uint32_t double_temp[], int full, int c,
}
if ((exp | fract[1] | fract[0]) != 0) {
if (full)
exp -= (1023 - 1); /* +1 since .1 vs 1. */
else
exp -= (127 - 1); /* +1 since .1 vs 1. */
exp -= (1023 - 1); /* +1 since .1 vs 1. */
fract[1] |= 0x80000000;
decexp = true; /* Wasn't zero */
} else
decexp = false; /* It was zero */
if (decexp && ((full && (double_temp[1] & 0x80000000))
|| (!full && (double_temp[0] & 0x80000000)))) {
if (decexp && (double_temp[1] & 0x80000000)) {
*buf++ = '-';
} else if (fplus)
*buf++ = '+';
@ -401,15 +384,9 @@ static int _to_float(char *buf, uint32_t double_temp[], int full, int c,
exp = 0;
} else
exp = precision + 1;
if (full) {
digit_count = 16;
if (exp > 16)
exp = 16;
} else {
digit_count = 8;
if (exp > 8)
exp = 8;
}
digit_count = 16;
if (exp > 16)
exp = 16;
ltemp[0] = 0;
ltemp[1] = 0x08000000;
@ -682,8 +659,8 @@ int _prf(int (*func)(), void *dest, char *format, va_list vargs)
#endif
}
c = _to_float(buf, double_temp, DOUBLE, c, falt, fplus,
fspace, precision);
c = _to_float(buf, double_temp, c, falt, fplus,
fspace, precision);
if (fplus || fspace || (buf[0] == '-'))
prefix = 1;
need_justifying = true;