/* atof_ieee.c - turn a Flonum into an IEEE floating point number
- Copyright (C) 1987, 92, 93, 94, 95, 96, 97, 1998
- Free Software Foundation, Inc.
+ Copyright (C) 1987-2016 Free Software Foundation, Inc.
This file is part of GAS, the GNU Assembler.
GAS 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, or (at your option)
+ the Free Software Foundation; either version 3, or (at your option)
any later version.
GAS is distributed in the hope that it will be useful,
You should have received a copy of the GNU General Public License
along with GAS; see the file COPYING. If not, write to the Free
- Software Foundation, 59 Temple Place - Suite 330, Boston, MA
- 02111-1307, USA. */
+ Software Foundation, 51 Franklin Street - Fifth Floor, Boston, MA
+ 02110-1301, USA. */
#include "as.h"
/* Flonums returned here. */
extern FLONUM_TYPE generic_floating_point_number;
-static int next_bits PARAMS ((int));
-static void unget_bits PARAMS ((int));
-static void make_invalid_floating_point_number PARAMS ((LITTLENUM_TYPE *));
-
-extern const char EXP_CHARS[];
-/* Precision in LittleNums. */
+/* Precision in LittleNums. */
/* Don't count the gap in the m68k extended precision format. */
-#define MAX_PRECISION (5)
-#define F_PRECISION (2)
-#define D_PRECISION (4)
-#define X_PRECISION (5)
-#define P_PRECISION (5)
+#define MAX_PRECISION 5
+#define F_PRECISION 2
+#define D_PRECISION 4
+#define X_PRECISION 5
+#define P_PRECISION 5
+
+/* Length in LittleNums of guard bits. */
+#define GUARD 2
-/* Length in LittleNums of guard bits. */
-#define GUARD (2)
+#ifndef TC_LARGEST_EXPONENT_IS_NORMAL
+#define TC_LARGEST_EXPONENT_IS_NORMAL(PRECISION) 0
+#endif
static const unsigned long mask[] =
{
0xffffffff,
};
\f
-
static int bits_left_in_littlenum;
static int littlenums_left;
static LITTLENUM_TYPE *littlenum_pointer;
static int
-next_bits (number_of_bits)
- int number_of_bits;
+next_bits (int number_of_bits)
{
int return_value;
if (!littlenums_left)
- return (0);
+ return 0;
+
if (number_of_bits >= bits_left_in_littlenum)
{
return_value = mask[bits_left_in_littlenum] & *littlenum_pointer;
{
bits_left_in_littlenum = LITTLENUM_NUMBER_OF_BITS - number_of_bits;
--littlenum_pointer;
- return_value |= (*littlenum_pointer >> bits_left_in_littlenum) & mask[number_of_bits];
+ return_value |=
+ (*littlenum_pointer >> bits_left_in_littlenum)
+ & mask[number_of_bits];
}
}
else
{
bits_left_in_littlenum -= number_of_bits;
- return_value = mask[number_of_bits] & (*littlenum_pointer >> bits_left_in_littlenum);
+ return_value =
+ mask[number_of_bits] & (*littlenum_pointer >> bits_left_in_littlenum);
}
- return (return_value);
+ return return_value;
}
-/* Num had better be less than LITTLENUM_NUMBER_OF_BITS */
+/* Num had better be less than LITTLENUM_NUMBER_OF_BITS. */
+
static void
-unget_bits (num)
- int num;
+unget_bits (int num)
{
if (!littlenums_left)
{
}
else if (bits_left_in_littlenum + num > LITTLENUM_NUMBER_OF_BITS)
{
- bits_left_in_littlenum = num - (LITTLENUM_NUMBER_OF_BITS - bits_left_in_littlenum);
+ bits_left_in_littlenum =
+ num - (LITTLENUM_NUMBER_OF_BITS - bits_left_in_littlenum);
++littlenum_pointer;
++littlenums_left;
}
}
static void
-make_invalid_floating_point_number (words)
- LITTLENUM_TYPE *words;
+make_invalid_floating_point_number (LITTLENUM_TYPE *words)
{
as_bad (_("cannot create floating-point number"));
- words[0] = (LITTLENUM_TYPE) ((unsigned) -1) >> 1; /* Zero the leftmost bit */
+ /* Zero the leftmost bit. */
+ words[0] = (LITTLENUM_TYPE) ((unsigned) -1) >> 1;
words[1] = (LITTLENUM_TYPE) -1;
words[2] = (LITTLENUM_TYPE) -1;
words[3] = (LITTLENUM_TYPE) -1;
words[5] = (LITTLENUM_TYPE) -1;
}
\f
-/************************************************************************\
- * Warning: this returns 16-bit LITTLENUMs. It is up to the caller *
- * to figure out any alignment problems and to conspire for the *
- * bytes/word to be emitted in the right order. Bigendians beware! *
- * *
-\************************************************************************/
+/* Warning: This returns 16-bit LITTLENUMs. It is up to the caller to
+ figure out any alignment problems and to conspire for the
+ bytes/word to be emitted in the right order. Bigendians beware! */
/* Note that atof-ieee always has X and P precisions enabled. it is up
to md_atof to filter them out if the target machine does not support
them. */
-/* Returns pointer past text consumed. */
+/* Returns pointer past text consumed. */
+
char *
-atof_ieee (str, what_kind, words)
- char *str; /* Text to convert to binary. */
- char what_kind; /* 'd', 'f', 'g', 'h' */
- LITTLENUM_TYPE *words; /* Build the binary here. */
+atof_ieee (char *str, /* Text to convert to binary. */
+ int what_kind, /* 'd', 'f', 'x', 'p'. */
+ LITTLENUM_TYPE *words) /* Build the binary here. */
{
- /* Extra bits for zeroed low-order bits. The 1st MAX_PRECISION are
- zeroed, the last contain flonum bits. */
+ /* Extra bits for zeroed low-order bits.
+ The 1st MAX_PRECISION are zeroed, the last contain flonum bits. */
static LITTLENUM_TYPE bits[MAX_PRECISION + MAX_PRECISION + GUARD];
char *return_value;
- /* Number of 16-bit words in the format. */
+ /* Number of 16-bit words in the format. */
int precision;
long exponent_bits;
FLONUM_TYPE save_gen_flonum;
generic_floating_point_number.sign = '\0';
/* Use more LittleNums than seems necessary: the highest flonum may
- have 15 leading 0 bits, so could be useless. */
+ have 15 leading 0 bits, so could be useless. */
memset (bits, '\0', sizeof (LITTLENUM_TYPE) * MAX_PRECISION);
case 'p':
case 'P':
-
precision = P_PRECISION;
exponent_bits = -1;
break;
&generic_floating_point_number))
{
make_invalid_floating_point_number (words);
- return (NULL);
+ return NULL;
}
gen_to_words (words, precision, exponent_bits);
}
/* Turn generic_floating_point_number into a real float/double/extended. */
+
int
-gen_to_words (words, precision, exponent_bits)
- LITTLENUM_TYPE *words;
- int precision;
- long exponent_bits;
+gen_to_words (LITTLENUM_TYPE *words, int precision, long exponent_bits)
{
int return_value = 0;
if (generic_floating_point_number.low > generic_floating_point_number.leader)
{
- /* 0.0e0 seen. */
+ /* 0.0e0 seen. */
if (generic_floating_point_number.sign == '+')
words[0] = 0x0000;
else
words[0] = 0x8000;
memset (&words[1], '\0',
(words_end - words - 1) * sizeof (LITTLENUM_TYPE));
- return (return_value);
+ return return_value;
}
- /* NaN: Do the right thing */
+ /* NaN: Do the right thing. */
if (generic_floating_point_number.sign == 0)
{
+ if (TC_LARGEST_EXPONENT_IS_NORMAL (precision))
+ as_warn (_("NaNs are not supported by this target\n"));
if (precision == F_PRECISION)
{
words[0] = 0x7fff;
words[3] = 0xffff;
words[4] = 0xffff;
words[5] = 0xffff;
-#else /* ! TC_M68K */
+#else /* ! TC_M68K */
#ifdef TC_I386
words[0] = 0xffff;
words[1] = 0xc000;
words[2] = 0;
words[3] = 0;
words[4] = 0;
-#else /* ! TC_I386 */
+#else /* ! TC_I386 */
abort ();
-#endif /* ! TC_I386 */
-#endif /* ! TC_M68K */
+#endif /* ! TC_I386 */
+#endif /* ! TC_M68K */
}
else
{
}
else if (generic_floating_point_number.sign == 'P')
{
- /* +INF: Do the right thing */
+ if (TC_LARGEST_EXPONENT_IS_NORMAL (precision))
+ as_warn (_("Infinities are not supported by this target\n"));
+
+ /* +INF: Do the right thing. */
if (precision == F_PRECISION)
{
words[0] = 0x7f80;
words[3] = 0;
words[4] = 0;
words[5] = 0;
-#else /* ! TC_M68K */
+#else /* ! TC_M68K */
#ifdef TC_I386
words[0] = 0x7fff;
words[1] = 0x8000;
words[2] = 0;
words[3] = 0;
words[4] = 0;
-#else /* ! TC_I386 */
+#else /* ! TC_I386 */
abort ();
-#endif /* ! TC_I386 */
-#endif /* ! TC_M68K */
+#endif /* ! TC_I386 */
+#endif /* ! TC_M68K */
}
else
{
words[2] = 0;
words[3] = 0;
}
- return (return_value);
+ return return_value;
}
else if (generic_floating_point_number.sign == 'N')
{
- /* Negative INF */
+ if (TC_LARGEST_EXPONENT_IS_NORMAL (precision))
+ as_warn (_("Infinities are not supported by this target\n"));
+
+ /* Negative INF. */
if (precision == F_PRECISION)
{
words[0] = 0xff80;
words[3] = 0;
words[4] = 0;
words[5] = 0;
-#else /* ! TC_M68K */
+#else /* ! TC_M68K */
#ifdef TC_I386
words[0] = 0xffff;
words[1] = 0x8000;
words[2] = 0;
words[3] = 0;
words[4] = 0;
-#else /* ! TC_I386 */
+#else /* ! TC_I386 */
abort ();
-#endif /* ! TC_I386 */
-#endif /* ! TC_M68K */
+#endif /* ! TC_I386 */
+#endif /* ! TC_M68K */
}
else
{
words[2] = 0x0;
words[3] = 0x0;
}
- return (return_value);
+ return return_value;
}
- /*
- * The floating point formats we support have:
- * Bit 15 is sign bit.
- * Bits 14:n are excess-whatever exponent.
- * Bits n-1:0 (if any) are most significant bits of fraction.
- * Bits 15:0 of the next word(s) are the next most significant bits.
- *
- * So we need: number of bits of exponent, number of bits of
- * mantissa.
- */
+
+ /* The floating point formats we support have:
+ Bit 15 is sign bit.
+ Bits 14:n are excess-whatever exponent.
+ Bits n-1:0 (if any) are most significant bits of fraction.
+ Bits 15:0 of the next word(s) are the next most significant bits.
+
+ So we need: number of bits of exponent, number of bits of
+ mantissa. */
bits_left_in_littlenum = LITTLENUM_NUMBER_OF_BITS;
littlenum_pointer = generic_floating_point_number.leader;
littlenums_left = (1
+ generic_floating_point_number.leader
- generic_floating_point_number.low);
- /* Seek (and forget) 1st significant bit */
- for (exponent_skippage = 0; !next_bits (1); ++exponent_skippage);;
+
+ /* Seek (and forget) 1st significant bit. */
+ for (exponent_skippage = 0; !next_bits (1); ++exponent_skippage);
exponent_1 = (generic_floating_point_number.exponent
+ generic_floating_point_number.leader
+ 1
- generic_floating_point_number.low);
+
/* Radix LITTLENUM_RADIX, point just higher than
- generic_floating_point_number.leader. */
+ generic_floating_point_number.leader. */
exponent_2 = exponent_1 * LITTLENUM_NUMBER_OF_BITS;
- /* Radix 2. */
+
+ /* Radix 2. */
exponent_3 = exponent_2 - exponent_skippage;
- /* Forget leading zeros, forget 1st bit. */
+
+ /* Forget leading zeros, forget 1st bit. */
exponent_4 = exponent_3 + ((1 << (exponent_bits - 1)) - 2);
- /* Offset exponent. */
+ /* Offset exponent. */
lp = words;
- /* Word 1. Sign, exponent and perhaps high bits. */
+ /* Word 1. Sign, exponent and perhaps high bits. */
word1 = ((generic_floating_point_number.sign == '+')
? 0
: (1 << (LITTLENUM_NUMBER_OF_BITS - 1)));
- /* Assume 2's complement integers. */
+ /* Assume 2's complement integers. */
if (exponent_4 <= 0)
{
int prec_bits;
unget_bits (1);
num_bits = -exponent_4;
- prec_bits = LITTLENUM_NUMBER_OF_BITS * precision - (exponent_bits + 1 + num_bits);
+ prec_bits =
+ LITTLENUM_NUMBER_OF_BITS * precision - (exponent_bits + 1 + num_bits);
#ifdef TC_I386
if (precision == X_PRECISION && exponent_bits == 15)
{
if (num_bits >= LITTLENUM_NUMBER_OF_BITS - exponent_bits)
{
- /* Bigger than one littlenum */
+ /* Bigger than one littlenum. */
num_bits -= (LITTLENUM_NUMBER_OF_BITS - 1) - exponent_bits;
*lp++ = word1;
- if (num_bits + exponent_bits + 1 >= precision * LITTLENUM_NUMBER_OF_BITS)
+ if (num_bits + exponent_bits + 1
+ > precision * LITTLENUM_NUMBER_OF_BITS)
{
- /* Exponent overflow */
+ /* Exponent overflow. */
make_invalid_floating_point_number (words);
- return (return_value);
+ return return_value;
}
#ifdef TC_M68K
if (precision == X_PRECISION && exponent_bits == 15)
}
else
{
- word1 |= next_bits ((LITTLENUM_NUMBER_OF_BITS - 1) - (exponent_bits + num_bits));
+ word1 |= next_bits ((LITTLENUM_NUMBER_OF_BITS - 1)
+ - (exponent_bits + num_bits));
*lp++ = word1;
}
}
while (lp < words_end)
*lp++ = next_bits (LITTLENUM_NUMBER_OF_BITS);
- /* Round the mantissa up, but don't change the number */
+ /* Round the mantissa up, but don't change the number. */
if (next_bits (1))
{
--lp;
- if (prec_bits > LITTLENUM_NUMBER_OF_BITS)
+ if (prec_bits >= LITTLENUM_NUMBER_OF_BITS)
{
int n = 0;
int tmp_bits;
--n;
tmp_bits -= LITTLENUM_NUMBER_OF_BITS;
}
- if (tmp_bits > LITTLENUM_NUMBER_OF_BITS || (lp[n] & mask[tmp_bits]) != mask[tmp_bits])
+ if (tmp_bits > LITTLENUM_NUMBER_OF_BITS
+ || (lp[n] & mask[tmp_bits]) != mask[tmp_bits]
+ || (prec_bits != (precision * LITTLENUM_NUMBER_OF_BITS
+ - exponent_bits - 1)
+#ifdef TC_I386
+ /* An extended precision float with only the integer
+ bit set would be invalid. That must be converted
+ to the smallest normalized number. */
+ && !(precision == X_PRECISION
+ && prec_bits == (precision * LITTLENUM_NUMBER_OF_BITS
+ - exponent_bits - 2))
+#endif
+ ))
{
unsigned long carry;
<< ((LITTLENUM_NUMBER_OF_BITS - 1)
- exponent_bits));
*lp++ = word1;
+#ifdef TC_I386
+ /* Set the integer bit in the extended precision format.
+ This cannot happen on the m68k where the mantissa
+ just overflows into the integer bit above. */
+ if (precision == X_PRECISION)
+ *lp++ = 1 << (LITTLENUM_NUMBER_OF_BITS - 1);
+#endif
while (lp < words_end)
*lp++ = 0;
}
}
- else if ((*lp & mask[prec_bits]) != mask[prec_bits])
+ else
*lp += 1;
}
return return_value;
}
- else if ((unsigned long) exponent_4 >= mask[exponent_bits])
+ else if ((unsigned long) exponent_4 > mask[exponent_bits]
+ || (! TC_LARGEST_EXPONENT_IS_NORMAL (precision)
+ && (unsigned long) exponent_4 == mask[exponent_bits]))
{
- /*
- * Exponent overflow. Lose immediately.
- */
-
- /*
- * We leave return_value alone: admit we read the
- * number, but return a floating exception
- * because we can't encode the number.
- */
+ /* Exponent overflow. Lose immediately. */
+
+ /* We leave return_value alone: admit we read the
+ number, but return a floating exception
+ because we can't encode the number. */
make_invalid_floating_point_number (words);
return return_value;
}
*lp++ = word1;
/* X_PRECISION is special: on the 68k, it has 16 bits of zero in the
- middle. Either way, it is then followed by a 1 bit. */
+ middle. Either way, it is then followed by a 1 bit. */
if (exponent_bits == 15 && precision == X_PRECISION)
{
#ifdef TC_M68K
| next_bits (LITTLENUM_NUMBER_OF_BITS - 1));
}
- /* The rest of the words are just mantissa bits. */
+ /* The rest of the words are just mantissa bits. */
while (lp < words_end)
*lp++ = next_bits (LITTLENUM_NUMBER_OF_BITS);
if (next_bits (1))
{
unsigned long carry;
- /*
- * Since the NEXT bit is a 1, round UP the mantissa.
- * The cunning design of these hidden-1 floats permits
- * us to let the mantissa overflow into the exponent, and
- * it 'does the right thing'. However, we lose if the
- * highest-order bit of the lowest-order word flips.
- * Is that clear?
- */
+ /* Since the NEXT bit is a 1, round UP the mantissa.
+ The cunning design of these hidden-1 floats permits
+ us to let the mantissa overflow into the exponent, and
+ it 'does the right thing'. However, we lose if the
+ highest-order bit of the lowest-order word flips.
+ Is that clear? */
/* #if (sizeof(carry)) < ((sizeof(bits[0]) * BITS_PER_CHAR) + 2)
Please allow at least 1 more bit in carry than is in a LITTLENUM.
don't get a sticky sign bit after shifting right, and that
permits us to propagate the carry without any masking of bits.
#endif */
- for (carry = 1, lp--; carry && (lp >= words); lp--)
+ for (carry = 1, lp--; carry; lp--)
{
carry = *lp + carry;
*lp = carry;
carry >>= LITTLENUM_NUMBER_OF_BITS;
+ if (lp == words)
+ break;
}
if (precision == X_PRECISION && exponent_bits == 15)
{
{
#ifdef TC_M68K
/* On the m68k there is a gap of 16 bits. We must
- explicitly propagate the carry into the exponent. */
+ explicitly propagate the carry into the exponent. */
words[0] += words[1];
words[1] = 0;
lp++;
#endif
- /* Put back the integer bit. */
+ /* Put back the integer bit. */
lp[1] |= 1 << (LITTLENUM_NUMBER_OF_BITS - 1);
}
- }
+ }
if ((word1 ^ *words) & (1 << (LITTLENUM_NUMBER_OF_BITS - 1)))
{
- /* We leave return_value alone: admit we read the
- * number, but return a floating exception
- * because we can't encode the number.
- */
+ /* We leave return_value alone: admit we read the number,
+ but return a floating exception because we can't encode
+ the number. */
*words &= ~(1 << (LITTLENUM_NUMBER_OF_BITS - 1));
- /* make_invalid_floating_point_number (words); */
- /* return return_value; */
}
}
- return (return_value);
-}
-
-#if 0 /* unused */
-/* This routine is a real kludge. Someone really should do it better,
- but I'm too lazy, and I don't understand this stuff all too well
- anyway. (JF) */
-static void
-int_to_gen (x)
- long x;
-{
- char buf[20];
- char *bufp;
-
- sprintf (buf, "%ld", x);
- bufp = &buf[0];
- if (atof_generic (&bufp, ".", EXP_CHARS, &generic_floating_point_number))
- as_bad (_("Error converting number to floating point (Exponent overflow?)"));
+ return return_value;
}
-#endif
#ifdef TEST
char *
sprintf (sbuf + strlen (sbuf), "%x %x %.12g\n", arr[0], arr[1], fv);
if (gen)
- {
- generic_floating_point_number = f;
- }
+ generic_floating_point_number = f;
return (sbuf);
}
+#endif
+
+#define MAX_LITTLENUMS 6
+
+/* This is a utility function called from various tc-*.c files. It
+ is here in order to reduce code duplication.
+
+ Turn a string at input_line_pointer into a floating point constant
+ of type TYPE (a character found in the FLT_CHARS macro), and store
+ it as LITTLENUMS in the bytes buffer LITP. The number of chars
+ emitted is stored in *SIZEP. BIG_WORDIAN is TRUE if the littlenums
+ should be emitted most significant littlenum first.
+ An error message is returned, or a NULL pointer if everything went OK. */
+
+const char *
+ieee_md_atof (int type,
+ char *litP,
+ int *sizeP,
+ bfd_boolean big_wordian)
+{
+ LITTLENUM_TYPE words[MAX_LITTLENUMS];
+ LITTLENUM_TYPE *wordP;
+ char *t;
+ int prec = 0;
+
+ if (strchr (FLT_CHARS, type) != NULL)
+ {
+ switch (type)
+ {
+ case 'f':
+ case 'F':
+ case 's':
+ case 'S':
+ prec = F_PRECISION;
+ break;
+
+ case 'd':
+ case 'D':
+ case 'r':
+ case 'R':
+ prec = D_PRECISION;
+ break;
+
+ case 't':
+ case 'T':
+ prec = X_PRECISION;
+ type = 'x'; /* This is what atof_ieee() understands. */
+ break;
+
+ case 'x':
+ case 'X':
+ case 'p':
+ case 'P':
+#ifdef TC_M68K
+ /* Note: on the m68k there is a gap of 16 bits (one littlenum)
+ between the exponent and mantissa. Hence the precision is
+ 6 and not 5. */
+ prec = P_PRECISION + 1;
+#else
+ prec = P_PRECISION;
#endif
+ break;
+
+ default:
+ break;
+ }
+ }
+ /* The 'f' and 'd' types are always recognised, even if the target has
+ not put them into the FLT_CHARS macro. This is because the 'f' type
+ can come from the .dc.s, .dcb.s, .float or .single pseudo-ops and the
+ 'd' type from the .dc.d, .dbc.d or .double pseudo-ops.
+
+ The 'x' type is not implicitly recongised however, even though it can
+ be generated by the .dc.x and .dbc.x pseudo-ops because not all targets
+ can support floating point values that big. ie the target has to
+ explicitly allow them by putting them into FLT_CHARS. */
+ else if (type == 'f')
+ prec = F_PRECISION;
+ else if (type == 'd')
+ prec = D_PRECISION;
+
+ if (prec == 0)
+ {
+ *sizeP = 0;
+ return _("Unrecognized or unsupported floating point constant");
+ }
+
+ gas_assert (prec <= MAX_LITTLENUMS);
+
+ t = atof_ieee (input_line_pointer, type, words);
+ if (t)
+ input_line_pointer = t;
-/* end of atof-ieee.c */
+ *sizeP = prec * sizeof (LITTLENUM_TYPE);
+
+ if (big_wordian)
+ {
+ for (wordP = words; prec --;)
+ {
+ md_number_to_chars (litP, (valueT) (* wordP ++), sizeof (LITTLENUM_TYPE));
+ litP += sizeof (LITTLENUM_TYPE);
+ }
+ }
+ else
+ {
+ for (wordP = words + prec; prec --;)
+ {
+ md_number_to_chars (litP, (valueT) (* -- wordP), sizeof (LITTLENUM_TYPE));
+ litP += sizeof (LITTLENUM_TYPE);
+ }
+ }
+
+ return NULL;
+}
projects / deliverable / binutils-gdb.git / blobdiff