/* Floating point routines for GDB, the GNU debugger.
- Copyright 1986, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995,
- 1996, 1997, 1998, 1999, 2000, 2001, 2003, 2004, 2005 Free Software
- Foundation, Inc.
+ Copyright (C) 1986, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996,
+ 1997, 1998, 1999, 2000, 2001, 2003, 2004, 2005, 2007, 2008, 2009
+ Free Software Foundation, Inc.
This file is part of GDB.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 2 of the License, or
+ the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
- along with this program; if not, write to the Free Software
- Foundation, Inc., 59 Temple Place - Suite 330,
- Boston, MA 02111-1307, USA. */
+ along with this program. If not, see <http://www.gnu.org/licenses/>. */
/* Support for converting target fp numbers into host DOUBLEST format. */
return result;
}
-/* Normalize the byte order of FROM into TO. If no normalization is needed
- then FMT->byteorder is returned and TO is not changed; otherwise the format
- of the normalized form in TO is returned. */
+/* Normalize the byte order of FROM into TO. If no normalization is
+ needed then FMT->byteorder is returned and TO is not changed;
+ otherwise the format of the normalized form in TO is returned. */
+
static enum floatformat_byteorders
floatformat_normalize_byteorder (const struct floatformat *fmt,
const void *from, void *to)
|| fmt->byteorder == floatformat_big)
return fmt->byteorder;
- gdb_assert (fmt->byteorder == floatformat_littlebyte_bigword);
-
words = fmt->totalsize / FLOATFORMAT_CHAR_BIT;
words >>= 2;
swapout = (unsigned char *)to;
swapin = (const unsigned char *)from;
- while (words-- > 0)
+ if (fmt->byteorder == floatformat_vax)
+ {
+ while (words-- > 0)
+ {
+ *swapout++ = swapin[1];
+ *swapout++ = swapin[0];
+ *swapout++ = swapin[3];
+ *swapout++ = swapin[2];
+ swapin += 4;
+ }
+ /* This may look weird, since VAX is little-endian, but it is
+ easier to translate to big-endian than to little-endian. */
+ return floatformat_big;
+ }
+ else
{
- *swapout++ = swapin[3];
- *swapout++ = swapin[2];
- *swapout++ = swapin[1];
- *swapout++ = swapin[0];
- swapin += 4;
+ gdb_assert (fmt->byteorder == floatformat_littlebyte_bigword);
+
+ while (words-- > 0)
+ {
+ *swapout++ = swapin[3];
+ *swapout++ = swapin[2];
+ *swapout++ = swapin[1];
+ *swapout++ = swapin[0];
+ swapin += 4;
+ }
+ return floatformat_big;
}
- return floatformat_big;
}
/* Convert from FMT to a DOUBLEST.
int special_exponent; /* It's a NaN, denorm or zero */
enum floatformat_byteorders order;
unsigned char newfrom[FLOATFORMAT_LARGEST_BYTES];
+ enum float_kind kind;
gdb_assert (fmt->totalsize
<= FLOATFORMAT_LARGEST_BYTES * FLOATFORMAT_CHAR_BIT);
+ /* For non-numbers, reuse libiberty's logic to find the correct
+ format. We do not lose any precision in this case by passing
+ through a double. */
+ kind = floatformat_classify (fmt, from);
+ if (kind == float_infinite || kind == float_nan)
+ {
+ double dto;
+ floatformat_to_double (fmt, from, &dto);
+ *to = (DOUBLEST) dto;
+ return;
+ }
+
order = floatformat_normalize_byteorder (fmt, ufrom, newfrom);
if (order != fmt->byteorder)
ufrom = newfrom;
+ if (fmt->split_half)
+ {
+ DOUBLEST dtop, dbot;
+ floatformat_to_doublest (fmt->split_half, ufrom, &dtop);
+ /* Preserve the sign of 0, which is the sign of the top
+ half. */
+ if (dtop == 0.0)
+ {
+ *to = dtop;
+ return;
+ }
+ floatformat_to_doublest (fmt->split_half,
+ ufrom + fmt->totalsize / FLOATFORMAT_CHAR_BIT / 2,
+ &dbot);
+ *to = dtop + dbot;
+ return;
+ }
+
exponent = get_field (ufrom, order, fmt->totalsize, fmt->exp_start,
fmt->exp_len);
/* Note that if exponent indicates a NaN, we can't really do anything useful
#endif /* HAVE_LONG_DOUBLE */
-/* The converse: convert the DOUBLEST *FROM to an extended float
- and store where TO points. Neither FROM nor TO have any alignment
+/* The converse: convert the DOUBLEST *FROM to an extended float and
+ store where TO points. Neither FROM nor TO have any alignment
restrictions. */
static void
convert_doublest_to_floatformat (CONST struct floatformat *fmt,
- const DOUBLEST *from,
- void *to)
+ const DOUBLEST *from, void *to)
{
DOUBLEST dfrom;
int exponent;
int mant_bits_left;
unsigned char *uto = (unsigned char *) to;
enum floatformat_byteorders order = fmt->byteorder;
+ unsigned char newto[FLOATFORMAT_LARGEST_BYTES];
- if (order == floatformat_littlebyte_bigword)
+ if (order != floatformat_little)
order = floatformat_big;
+ if (order != fmt->byteorder)
+ uto = newto;
+
memcpy (&dfrom, from, sizeof (dfrom));
memset (uto, 0, (fmt->totalsize + FLOATFORMAT_CHAR_BIT - 1)
/ FLOATFORMAT_CHAR_BIT);
+
+ if (fmt->split_half)
+ {
+ /* Use static volatile to ensure that any excess precision is
+ removed via storing in memory, and so the top half really is
+ the result of converting to double. */
+ static volatile double dtop, dbot;
+ DOUBLEST dtopnv, dbotnv;
+ dtop = (double) dfrom;
+ /* If the rounded top half is Inf, the bottom must be 0 not NaN
+ or Inf. */
+ if (dtop + dtop == dtop && dtop != 0.0)
+ dbot = 0.0;
+ else
+ dbot = (double) (dfrom - (DOUBLEST) dtop);
+ dtopnv = dtop;
+ dbotnv = dbot;
+ floatformat_from_doublest (fmt->split_half, &dtopnv, uto);
+ floatformat_from_doublest (fmt->split_half, &dbotnv,
+ (uto
+ + fmt->totalsize / FLOATFORMAT_CHAR_BIT / 2));
+ return;
+ }
+
if (dfrom == 0)
return; /* Result is zero */
if (dfrom != dfrom) /* Result is NaN */
finalize_byteorder:
/* Do we need to byte-swap the words in the result? */
if (order != fmt->byteorder)
- {
- int words;
- unsigned char *curword = uto;
- unsigned char tmp;
-
- words = fmt->totalsize / FLOATFORMAT_CHAR_BIT;
- words >>= 2;
- while (words-- > 0)
- {
- tmp = curword[0];
- curword[0] = curword[3];
- curword[3] = tmp;
- tmp = curword[1];
- curword[1] = curword[2];
- curword[2] = tmp;
- curword += 4;
- }
- }
+ floatformat_normalize_byteorder (fmt, newto, to);
}
/* Check if VAL (which is assumed to be a floating point number whose
/* Check if VAL is "not a number" (NaN) for FMT. */
-int
-floatformat_is_nan (const struct floatformat *fmt,
- const bfd_byte *uval)
+enum float_kind
+floatformat_classify (const struct floatformat *fmt,
+ const bfd_byte *uval)
{
long exponent;
unsigned long mant;
int mant_bits_left;
enum floatformat_byteorders order;
unsigned char newfrom[FLOATFORMAT_LARGEST_BYTES];
+ int mant_zero;
gdb_assert (fmt != NULL);
gdb_assert (fmt->totalsize
if (order != fmt->byteorder)
uval = newfrom;
- if (! fmt->exp_nan)
- return 0;
-
exponent = get_field (uval, order, fmt->totalsize, fmt->exp_start,
fmt->exp_len);
- if (exponent != fmt->exp_nan)
- return 0;
-
mant_bits_left = fmt->man_len;
mant_off = fmt->man_start;
+ mant_zero = 1;
while (mant_bits_left > 0)
{
mant_bits = min (mant_bits_left, 32);
mant &= ~(1 << (mant_bits - 1));
if (mant)
- return 1;
+ {
+ mant_zero = 0;
+ break;
+ }
mant_off += mant_bits;
mant_bits_left -= mant_bits;
}
- return 0;
+ /* If exp_nan is not set, assume that inf, NaN, and subnormals are not
+ supported. */
+ if (! fmt->exp_nan)
+ {
+ if (mant_zero)
+ return float_zero;
+ else
+ return float_normal;
+ }
+
+ if (exponent == 0 && !mant_zero)
+ return float_subnormal;
+
+ if (exponent == fmt->exp_nan)
+ {
+ if (mant_zero)
+ return float_infinite;
+ else
+ return float_nan;
+ }
+
+ if (mant_zero)
+ return float_zero;
+
+ return float_normal;
}
/* Convert the mantissa of VAL (which is assumed to be a floating
int mant_bits_left;
static char res[50];
char buf[9];
+ int len;
enum floatformat_byteorders order;
unsigned char newfrom[FLOATFORMAT_LARGEST_BYTES];
mant = get_field (uval, order, fmt->totalsize, mant_off, mant_bits);
- sprintf (res, "%lx", mant);
+ len = xsnprintf (res, sizeof res, "%lx", mant);
mant_off += mant_bits;
mant_bits_left -= mant_bits;
-
+
while (mant_bits_left > 0)
{
mant = get_field (uval, order, fmt->totalsize, mant_off, 32);
- sprintf (buf, "%08lx", mant);
+ xsnprintf (buf, sizeof buf, "%08lx", mant);
+ gdb_assert (len + strlen (buf) <= sizeof res);
strcat (res, buf);
mant_off += 32;
floatformat_from_length (int len)
{
const struct floatformat *format;
- if (len * TARGET_CHAR_BIT == TARGET_FLOAT_BIT)
- format = TARGET_FLOAT_FORMAT;
- else if (len * TARGET_CHAR_BIT == TARGET_DOUBLE_BIT)
- format = TARGET_DOUBLE_FORMAT;
- else if (len * TARGET_CHAR_BIT == TARGET_LONG_DOUBLE_BIT)
- format = TARGET_LONG_DOUBLE_FORMAT;
+ if (len * TARGET_CHAR_BIT == gdbarch_float_bit (current_gdbarch))
+ format = gdbarch_float_format (current_gdbarch)
+ [gdbarch_byte_order (current_gdbarch)];
+ else if (len * TARGET_CHAR_BIT == gdbarch_double_bit (current_gdbarch))
+ format = gdbarch_double_format (current_gdbarch)
+ [gdbarch_byte_order (current_gdbarch)];
+ else if (len * TARGET_CHAR_BIT == gdbarch_long_double_bit (current_gdbarch))
+ format = gdbarch_long_double_format (current_gdbarch)
+ [gdbarch_byte_order (current_gdbarch)];
/* On i386 the 'long double' type takes 96 bits,
while the real number of used bits is only 80,
both in processor and in memory.
The code below accepts the real bit size. */
- else if ((TARGET_LONG_DOUBLE_FORMAT != NULL)
+ else if ((gdbarch_long_double_format (current_gdbarch) != NULL)
&& (len * TARGET_CHAR_BIT ==
- TARGET_LONG_DOUBLE_FORMAT->totalsize))
- format = TARGET_LONG_DOUBLE_FORMAT;
+ gdbarch_long_double_format (current_gdbarch)[0]->totalsize))
+ format = gdbarch_long_double_format (current_gdbarch)
+ [gdbarch_byte_order (current_gdbarch)];
else
format = NULL;
if (format == NULL)
{
gdb_assert (TYPE_CODE (type) == TYPE_CODE_FLT);
if (TYPE_FLOATFORMAT (type) != NULL)
- return TYPE_FLOATFORMAT (type);
+ return TYPE_FLOATFORMAT (type)[gdbarch_byte_order (current_gdbarch)];
else
return floatformat_from_length (TYPE_LENGTH (type));
}
specific code? stabs?) so handle that here as a special case. */
return extract_floating_by_length (addr, TYPE_LENGTH (type));
- floatformat_to_doublest (TYPE_FLOATFORMAT (type), addr, &retval);
+ floatformat_to_doublest
+ (TYPE_FLOATFORMAT (type)[gdbarch_byte_order (current_gdbarch)],
+ addr, &retval);
return retval;
}
specific code? stabs?) so handle that here as a special case. */
store_floating_by_length (addr, TYPE_LENGTH (type), val);
else
- floatformat_from_doublest (TYPE_FLOATFORMAT (type), &val, addr);
+ floatformat_from_doublest
+ (TYPE_FLOATFORMAT (type)[gdbarch_byte_order (current_gdbarch)],
+ &val, addr);
}
/* Convert a floating-point number of type FROM_TYPE from a
else
{
/* The floating-point types don't match. The best we can do
- (aport from simulating the target FPU) is converting to the
+ (apart from simulating the target FPU) is converting to the
widest floating-point type supported by the host, and then
again to the desired type. */
DOUBLEST d;
projects / deliverable / binutils-gdb.git / blobdiff