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Diffstat (limited to 'contrib/binutils/libiberty/floatformat.c')
-rw-r--r--contrib/binutils/libiberty/floatformat.c401
1 files changed, 0 insertions, 401 deletions
diff --git a/contrib/binutils/libiberty/floatformat.c b/contrib/binutils/libiberty/floatformat.c
deleted file mode 100644
index 7f6086f43068..000000000000
--- a/contrib/binutils/libiberty/floatformat.c
+++ /dev/null
@@ -1,401 +0,0 @@
-/* IEEE floating point support routines, for GDB, the GNU Debugger.
- Copyright (C) 1991, 1994 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
-(at your option) any later version.
-
-This program is distributed in the hope that it will be useful,
-but WITHOUT ANY WARRANTY; without even the implied warranty of
-MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-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. */
-
-#include "floatformat.h"
-#include <math.h> /* ldexp */
-#ifdef __STDC__
-#include <stddef.h>
-extern void *memcpy (void *s1, const void *s2, size_t n);
-extern void *memset (void *s, int c, size_t n);
-#else
-extern char *memcpy ();
-extern char *memset ();
-#endif
-
-/* The odds that CHAR_BIT will be anything but 8 are low enough that I'm not
- going to bother with trying to muck around with whether it is defined in
- a system header, what we do if not, etc. */
-#define FLOATFORMAT_CHAR_BIT 8
-
-/* floatformats for IEEE single and double, big and little endian. */
-const struct floatformat floatformat_ieee_single_big =
-{
- floatformat_big, 32, 0, 1, 8, 127, 255, 9, 23, floatformat_intbit_no
-};
-const struct floatformat floatformat_ieee_single_little =
-{
- floatformat_little, 32, 0, 1, 8, 127, 255, 9, 23, floatformat_intbit_no
-};
-const struct floatformat floatformat_ieee_double_big =
-{
- floatformat_big, 64, 0, 1, 11, 1023, 2047, 12, 52, floatformat_intbit_no
-};
-const struct floatformat floatformat_ieee_double_little =
-{
- floatformat_little, 64, 0, 1, 11, 1023, 2047, 12, 52, floatformat_intbit_no
-};
-
-/* floatformat for IEEE double, little endian byte order, with big endian word
- ordering, as on the ARM. */
-
-const struct floatformat floatformat_ieee_double_littlebyte_bigword =
-{
- floatformat_littlebyte_bigword, 64, 0, 1, 11, 1023, 2047, 12, 52, floatformat_intbit_no
-};
-
-const struct floatformat floatformat_i387_ext =
-{
- floatformat_little, 80, 0, 1, 15, 0x3fff, 0x7fff, 16, 64,
- floatformat_intbit_yes
-};
-const struct floatformat floatformat_m68881_ext =
-{
- /* Note that the bits from 16 to 31 are unused. */
- floatformat_big, 96, 0, 1, 15, 0x3fff, 0x7fff, 32, 64, floatformat_intbit_yes
-};
-const struct floatformat floatformat_i960_ext =
-{
- /* Note that the bits from 0 to 15 are unused. */
- floatformat_little, 96, 16, 17, 15, 0x3fff, 0x7fff, 32, 64,
- floatformat_intbit_yes
-};
-const struct floatformat floatformat_m88110_ext =
-{
-#ifdef HARRIS_FLOAT_FORMAT
- /* Harris uses raw format 128 bytes long, but the number is just an ieee
- double, and the last 64 bits are wasted. */
- floatformat_big,128, 0, 1, 11, 0x3ff, 0x7ff, 12, 52,
- floatformat_intbit_no
-#else
- floatformat_big, 80, 0, 1, 15, 0x3fff, 0x7fff, 16, 64,
- floatformat_intbit_yes
-#endif /* HARRIS_FLOAT_FORMAT */
-};
-const struct floatformat floatformat_arm_ext =
-{
- /* Bits 1 to 16 are unused. */
- floatformat_big, 96, 0, 17, 15, 0x3fff, 0x7fff, 32, 64,
- floatformat_intbit_yes
-};
-
-static unsigned long get_field PARAMS ((unsigned char *,
- enum floatformat_byteorders,
- unsigned int,
- unsigned int,
- unsigned int));
-
-/* Extract a field which starts at START and is LEN bytes long. DATA and
- TOTAL_LEN are the thing we are extracting it from, in byteorder ORDER. */
-static unsigned long
-get_field (data, order, total_len, start, len)
- unsigned char *data;
- enum floatformat_byteorders order;
- unsigned int total_len;
- unsigned int start;
- unsigned int len;
-{
- unsigned long result;
- unsigned int cur_byte;
- int cur_bitshift;
-
- /* Start at the least significant part of the field. */
- cur_byte = (start + len) / FLOATFORMAT_CHAR_BIT;
- if (order == floatformat_little)
- cur_byte = (total_len / FLOATFORMAT_CHAR_BIT) - cur_byte - 1;
- cur_bitshift =
- ((start + len) % FLOATFORMAT_CHAR_BIT) - FLOATFORMAT_CHAR_BIT;
- result = *(data + cur_byte) >> (-cur_bitshift);
- cur_bitshift += FLOATFORMAT_CHAR_BIT;
- if (order == floatformat_little)
- ++cur_byte;
- else
- --cur_byte;
-
- /* Move towards the most significant part of the field. */
- while (cur_bitshift < len)
- {
- if (len - cur_bitshift < FLOATFORMAT_CHAR_BIT)
- /* This is the last byte; zero out the bits which are not part of
- this field. */
- result |=
- (*(data + cur_byte) & ((1 << (len - cur_bitshift)) - 1))
- << cur_bitshift;
- else
- result |= *(data + cur_byte) << cur_bitshift;
- cur_bitshift += FLOATFORMAT_CHAR_BIT;
- if (order == floatformat_little)
- ++cur_byte;
- else
- --cur_byte;
- }
- return result;
-}
-
-#ifndef min
-#define min(a, b) ((a) < (b) ? (a) : (b))
-#endif
-
-/* Convert from FMT to a double.
- FROM is the address of the extended float.
- Store the double in *TO. */
-
-void
-floatformat_to_double (fmt, from, to)
- const struct floatformat *fmt;
- char *from;
- double *to;
-{
- unsigned char *ufrom = (unsigned char *)from;
- double dto;
- long exponent;
- unsigned long mant;
- unsigned int mant_bits, mant_off;
- int mant_bits_left;
- int special_exponent; /* It's a NaN, denorm or zero */
-
- exponent = get_field (ufrom, fmt->byteorder, fmt->totalsize,
- fmt->exp_start, fmt->exp_len);
- /* Note that if exponent indicates a NaN, we can't really do anything useful
- (not knowing if the host has NaN's, or how to build one). So it will
- end up as an infinity or something close; that is OK. */
-
- mant_bits_left = fmt->man_len;
- mant_off = fmt->man_start;
- dto = 0.0;
-
- special_exponent = exponent == 0 || exponent == fmt->exp_nan;
-
- /* Don't bias zero's, denorms or NaNs. */
- if (!special_exponent)
- exponent -= fmt->exp_bias;
-
- /* Build the result algebraically. Might go infinite, underflow, etc;
- who cares. */
-
- /* If this format uses a hidden bit, explicitly add it in now. Otherwise,
- increment the exponent by one to account for the integer bit. */
-
- if (!special_exponent)
- if (fmt->intbit == floatformat_intbit_no)
- dto = ldexp (1.0, exponent);
- else
- exponent++;
-
- while (mant_bits_left > 0)
- {
- mant_bits = min (mant_bits_left, 32);
-
- mant = get_field (ufrom, fmt->byteorder, fmt->totalsize,
- mant_off, mant_bits);
-
- dto += ldexp ((double)mant, exponent - mant_bits);
- exponent -= mant_bits;
- mant_off += mant_bits;
- mant_bits_left -= mant_bits;
- }
-
- /* Negate it if negative. */
- if (get_field (ufrom, fmt->byteorder, fmt->totalsize, fmt->sign_start, 1))
- dto = -dto;
- *to = dto;
-}
-
-static void put_field PARAMS ((unsigned char *, enum floatformat_byteorders,
- unsigned int,
- unsigned int,
- unsigned int,
- unsigned long));
-
-/* Set a field which starts at START and is LEN bytes long. DATA and
- TOTAL_LEN are the thing we are extracting it from, in byteorder ORDER. */
-static void
-put_field (data, order, total_len, start, len, stuff_to_put)
- unsigned char *data;
- enum floatformat_byteorders order;
- unsigned int total_len;
- unsigned int start;
- unsigned int len;
- unsigned long stuff_to_put;
-{
- unsigned int cur_byte;
- int cur_bitshift;
-
- /* Start at the least significant part of the field. */
- cur_byte = (start + len) / FLOATFORMAT_CHAR_BIT;
- if (order == floatformat_little)
- cur_byte = (total_len / FLOATFORMAT_CHAR_BIT) - cur_byte - 1;
- cur_bitshift =
- ((start + len) % FLOATFORMAT_CHAR_BIT) - FLOATFORMAT_CHAR_BIT;
- *(data + cur_byte) &=
- ~(((1 << ((start + len) % FLOATFORMAT_CHAR_BIT)) - 1) << (-cur_bitshift));
- *(data + cur_byte) |=
- (stuff_to_put & ((1 << FLOATFORMAT_CHAR_BIT) - 1)) << (-cur_bitshift);
- cur_bitshift += FLOATFORMAT_CHAR_BIT;
- if (order == floatformat_little)
- ++cur_byte;
- else
- --cur_byte;
-
- /* Move towards the most significant part of the field. */
- while (cur_bitshift < len)
- {
- if (len - cur_bitshift < FLOATFORMAT_CHAR_BIT)
- {
- /* This is the last byte. */
- *(data + cur_byte) &=
- ~((1 << (len - cur_bitshift)) - 1);
- *(data + cur_byte) |= (stuff_to_put >> cur_bitshift);
- }
- else
- *(data + cur_byte) = ((stuff_to_put >> cur_bitshift)
- & ((1 << FLOATFORMAT_CHAR_BIT) - 1));
- cur_bitshift += FLOATFORMAT_CHAR_BIT;
- if (order == floatformat_little)
- ++cur_byte;
- else
- --cur_byte;
- }
-}
-
-/* The converse: convert the double *FROM to an extended float
- and store where TO points. Neither FROM nor TO have any alignment
- restrictions. */
-
-void
-floatformat_from_double (fmt, from, to)
- CONST struct floatformat *fmt;
- double *from;
- char *to;
-{
- double dfrom;
- int exponent;
- double mant;
- unsigned int mant_bits, mant_off;
- int mant_bits_left;
- unsigned char *uto = (unsigned char *)to;
-
- memcpy (&dfrom, from, sizeof (dfrom));
- memset (uto, 0, fmt->totalsize / FLOATFORMAT_CHAR_BIT);
- if (dfrom == 0)
- return; /* Result is zero */
- if (dfrom != dfrom)
- {
- /* From is NaN */
- put_field (uto, fmt->byteorder, fmt->totalsize, fmt->exp_start,
- fmt->exp_len, fmt->exp_nan);
- /* Be sure it's not infinity, but NaN value is irrel */
- put_field (uto, fmt->byteorder, fmt->totalsize, fmt->man_start,
- 32, 1);
- return;
- }
-
- /* If negative, set the sign bit. */
- if (dfrom < 0)
- {
- put_field (uto, fmt->byteorder, fmt->totalsize, fmt->sign_start, 1, 1);
- dfrom = -dfrom;
- }
-
- /* How to tell an infinity from an ordinary number? FIXME-someday */
-
- mant = frexp (dfrom, &exponent);
- put_field (uto, fmt->byteorder, fmt->totalsize, fmt->exp_start, fmt->exp_len,
- exponent + fmt->exp_bias - 1);
-
- mant_bits_left = fmt->man_len;
- mant_off = fmt->man_start;
- while (mant_bits_left > 0)
- {
- unsigned long mant_long;
- mant_bits = mant_bits_left < 32 ? mant_bits_left : 32;
-
- mant *= 4294967296.0;
- mant_long = (unsigned long)mant;
- mant -= mant_long;
-
- /* If the integer bit is implicit, then we need to discard it.
- If we are discarding a zero, we should be (but are not) creating
- a denormalized number which means adjusting the exponent
- (I think). */
- if (mant_bits_left == fmt->man_len
- && fmt->intbit == floatformat_intbit_no)
- {
- mant_long &= 0x7fffffff;
- mant_bits -= 1;
- }
- else if (mant_bits < 32)
- {
- /* The bits we want are in the most significant MANT_BITS bits of
- mant_long. Move them to the least significant. */
- mant_long >>= 32 - mant_bits;
- }
-
- put_field (uto, fmt->byteorder, fmt->totalsize,
- mant_off, mant_bits, mant_long);
- mant_off += mant_bits;
- mant_bits_left -= mant_bits;
- }
-}
-
-
-#ifdef IEEE_DEBUG
-
-/* This is to be run on a host which uses IEEE floating point. */
-
-void
-ieee_test (n)
- double n;
-{
- double result;
- char exten[16];
-
- floatformat_to_double (&floatformat_ieee_double_big, &n, &result);
- if (n != result)
- printf ("Differ(to): %.20g -> %.20g\n", n, result);
- floatformat_from_double (&floatformat_ieee_double_big, &n, &result);
- if (n != result)
- printf ("Differ(from): %.20g -> %.20g\n", n, result);
-
- floatformat_from_double (&floatformat_m68881_ext, &n, exten);
- floatformat_to_double (&floatformat_m68881_ext, exten, &result);
- if (n != result)
- printf ("Differ(to+from): %.20g -> %.20g\n", n, result);
-
-#if IEEE_DEBUG > 1
- /* This is to be run on a host which uses 68881 format. */
- {
- long double ex = *(long double *)exten;
- if (ex != n)
- printf ("Differ(from vs. extended): %.20g\n", n);
- }
-#endif
-}
-
-int
-main ()
-{
- ieee_test (0.5);
- ieee_test (256.0);
- ieee_test (0.12345);
- ieee_test (234235.78907234);
- ieee_test (-512.0);
- ieee_test (-0.004321);
- return 0;
-}
-#endif
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