/* atof_ieee.c - turn a Flonum into an IEEE floating point number
Copyright (C) 1987 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 1, or (at your option)
-any later version.
-
-GAS 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 GAS; see the file COPYING. If not, write to
-the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
+
+ 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)
+ any later version.
+
+ GAS 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 GAS; see the file COPYING. If not, write to
+ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
#include "as.h"
#endif
extern char EXP_CHARS[];
- /* Precision in LittleNums. */
+/* Precision in LittleNums. */
#define MAX_PRECISION (6)
#define F_PRECISION (2)
#define D_PRECISION (4)
#define X_PRECISION (6)
#define P_PRECISION (6)
- /* Length in LittleNums of guard bits. */
+/* Length in LittleNums of guard bits. */
#define GUARD (2)
static unsigned long mask [] = {
- 0x00000000,
- 0x00000001,
- 0x00000003,
- 0x00000007,
- 0x0000000f,
- 0x0000001f,
- 0x0000003f,
- 0x0000007f,
- 0x000000ff,
- 0x000001ff,
- 0x000003ff,
- 0x000007ff,
- 0x00000fff,
- 0x00001fff,
- 0x00003fff,
- 0x00007fff,
- 0x0000ffff,
- 0x0001ffff,
- 0x0003ffff,
- 0x0007ffff,
- 0x000fffff,
- 0x001fffff,
- 0x003fffff,
- 0x007fffff,
- 0x00ffffff,
- 0x01ffffff,
- 0x03ffffff,
- 0x07ffffff,
- 0x0fffffff,
- 0x1fffffff,
- 0x3fffffff,
- 0x7fffffff,
- 0xffffffff
- };
+ 0x00000000,
+ 0x00000001,
+ 0x00000003,
+ 0x00000007,
+ 0x0000000f,
+ 0x0000001f,
+ 0x0000003f,
+ 0x0000007f,
+ 0x000000ff,
+ 0x000001ff,
+ 0x000003ff,
+ 0x000007ff,
+ 0x00000fff,
+ 0x00001fff,
+ 0x00003fff,
+ 0x00007fff,
+ 0x0000ffff,
+ 0x0001ffff,
+ 0x0003ffff,
+ 0x0007ffff,
+ 0x000fffff,
+ 0x001fffff,
+ 0x003fffff,
+ 0x007fffff,
+ 0x00ffffff,
+ 0x01ffffff,
+ 0x03ffffff,
+ 0x07ffffff,
+ 0x0fffffff,
+ 0x1fffffff,
+ 0x3fffffff,
+ 0x7fffffff,
+ 0xffffffff
+ };
\f
static int bits_left_in_littlenum;
static LITTLENUM_TYPE *littlenum_pointer;
static int
-next_bits (number_of_bits)
- int number_of_bits;
+ next_bits (number_of_bits)
+int number_of_bits;
{
- int return_value;
-
- if(!littlenums_left)
- return 0;
- if (number_of_bits >= bits_left_in_littlenum)
- {
- return_value = mask [bits_left_in_littlenum] & *littlenum_pointer;
- number_of_bits -= bits_left_in_littlenum;
- return_value <<= number_of_bits;
- if(--littlenums_left) {
- 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];
- }
- }
- else
- {
- bits_left_in_littlenum -= number_of_bits;
- return_value = mask [number_of_bits] & (*littlenum_pointer>>bits_left_in_littlenum);
- }
- return (return_value);
+ int return_value;
+
+ if(!littlenums_left)
+ return 0;
+ if (number_of_bits >= bits_left_in_littlenum)
+ {
+ return_value = mask [bits_left_in_littlenum] & *littlenum_pointer;
+ number_of_bits -= bits_left_in_littlenum;
+ return_value <<= number_of_bits;
+ if(--littlenums_left) {
+ 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];
+ }
+ }
+ else
+ {
+ bits_left_in_littlenum -= number_of_bits;
+ return_value = mask [number_of_bits] & (*littlenum_pointer>>bits_left_in_littlenum);
+ }
+ return (return_value);
}
/* Num had better be less than LITTLENUM_NUMBER_OF_BITS */
static void
-unget_bits(num)
+ unget_bits(num)
int num;
{
if(!littlenums_left) {
++littlenum_pointer;
++littlenums_left;
} else
- bits_left_in_littlenum+=num;
+ bits_left_in_littlenum+=num;
}
static void
-make_invalid_floating_point_number (words)
- LITTLENUM_TYPE * words;
+ make_invalid_floating_point_number (words)
+LITTLENUM_TYPE * words;
{
as_bad("cannot create floating-point number");
words[0]= ((unsigned)-1)>>1; /* Zero the leftmost bit */
}
\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. */
char * /* Return pointer past text consumed. */
-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 (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. */
{
static LITTLENUM_TYPE bits [MAX_PRECISION + MAX_PRECISION + GUARD];
- /* 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. */
char * return_value;
int precision; /* Number of 16-bit words in the format. */
long exponent_bits;
-
+ FLONUM_TYPE save_gen_flonum;
+
+ /* We have to save the generic_floating_point_number because it
+ contains storage allocation about the array of LITTLENUMs
+ where the value is actually stored. We will allocate our
+ own array of littlenums below, but have to restore the global
+ one on exit. */
+ save_gen_flonum = generic_floating_point_number;
+
return_value = str;
generic_floating_point_number.low = bits + MAX_PRECISION;
generic_floating_point_number.high = NULL;
generic_floating_point_number.leader = NULL;
generic_floating_point_number.exponent = NULL;
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. */
-
+
+ /* Use more LittleNums than seems */
+ /* necessary: the highest flonum may have */
+ /* 15 leading 0 bits, so could be useless. */
+
bzero (bits, sizeof(LITTLENUM_TYPE) * MAX_PRECISION);
-
+
switch(what_kind) {
case 'f':
case 'F':
precision = F_PRECISION;
exponent_bits = 8;
break;
-
+
case 'd':
case 'D':
case 'r':
precision = D_PRECISION;
exponent_bits = 11;
break;
-
+
case 'x':
case 'X':
case 'e':
precision = X_PRECISION;
exponent_bits = 15;
break;
-
+
case 'p':
case 'P':
precision = P_PRECISION;
exponent_bits= -1;
break;
-
+
default:
make_invalid_floating_point_number (words);
return NULL;
}
-
+
generic_floating_point_number.high = generic_floating_point_number.low + precision - 1 + GUARD;
-
+
if (atof_generic (& return_value, ".", EXP_CHARS, & generic_floating_point_number)) {
/* as_bad("Error converting floating point number (Exponent overflow?)"); */
make_invalid_floating_point_number (words);
return NULL;
}
gen_to_words(words, precision, exponent_bits);
+
+ /* Restore the generic_floating_point_number's storage alloc
+ (and everything else). */
+ generic_floating_point_number = save_gen_flonum;
+
return return_value;
}
long exponent_bits;
{
int return_value=0;
-
+
long exponent_1;
long exponent_2;
long exponent_3;
int exponent_skippage;
LITTLENUM_TYPE word1;
LITTLENUM_TYPE * lp;
-
+
if (generic_floating_point_number.low > generic_floating_point_number.leader) {
/* 0.0e0 seen. */
if(generic_floating_point_number.sign=='+')
- words[0]=0x0000;
+ words[0]=0x0000;
else
- words[0]=0x8000;
+ words[0]=0x8000;
bzero (&words[1], sizeof(LITTLENUM_TYPE) * (precision-1));
return return_value;
}
-
+
/* NaN: Do the right thing */
if(generic_floating_point_number.sign==0) {
if(precision==F_PRECISION) {
}
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 ++)
- ;
+ ;
exponent_1 = generic_floating_point_number.exponent + generic_floating_point_number.leader + 1 -
- generic_floating_point_number.low;
+ generic_floating_point_number.low;
/* Radix LITTLENUM_RADIX, point just higher than generic_floating_point_number.leader. */
exponent_2 = exponent_1 * LITTLENUM_NUMBER_OF_BITS;
/* Radix 2. */
/* Forget leading zeros, forget 1st bit. */
exponent_4 = exponent_3 + ((1 << (exponent_bits - 1)) - 2);
/* Offset exponent. */
-
+
lp = words;
-
+
/* 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. */
if(exponent_4<1 && exponent_4>=-62) {
int prec_bits;
int num_bits;
-
+
unget_bits(1);
num_bits= -exponent_4;
prec_bits=LITTLENUM_NUMBER_OF_BITS*precision-(exponent_bits+1+num_bits);
if(precision==X_PRECISION && exponent_bits==15)
- prec_bits-=LITTLENUM_NUMBER_OF_BITS+1;
-
+ prec_bits-=LITTLENUM_NUMBER_OF_BITS+1;
+
if(num_bits>=LITTLENUM_NUMBER_OF_BITS-exponent_bits) {
/* Bigger than one littlenum */
num_bits-=(LITTLENUM_NUMBER_OF_BITS-1)-exponent_bits;
*lp++=0;
}
if(num_bits)
- *lp++=next_bits(LITTLENUM_NUMBER_OF_BITS-(num_bits));
+ *lp++=next_bits(LITTLENUM_NUMBER_OF_BITS-(num_bits));
} else {
if(precision==X_PRECISION && exponent_bits==15) {
*lp++=word1;
*lp++=0;
*lp++=next_bits(LITTLENUM_NUMBER_OF_BITS-1);
} else if(num_bits==LITTLENUM_NUMBER_OF_BITS-1)
- *lp++=0;
+ *lp++=0;
else
- *lp++=next_bits(LITTLENUM_NUMBER_OF_BITS-1-num_bits);
+ *lp++=next_bits(LITTLENUM_NUMBER_OF_BITS-1-num_bits);
num_bits=0;
} else {
word1|= next_bits ((LITTLENUM_NUMBER_OF_BITS-1) - (exponent_bits+num_bits));
}
}
while(lp<words+precision)
- *lp++=next_bits(LITTLENUM_NUMBER_OF_BITS);
-
+ *lp++=next_bits(LITTLENUM_NUMBER_OF_BITS);
+
/* Round the mantissa up, but don't change the number */
if(next_bits(1)) {
--lp;
if(prec_bits>LITTLENUM_NUMBER_OF_BITS) {
int n = 0;
int tmp_bits;
-
+
n=0;
tmp_bits=prec_bits;
while(tmp_bits>LITTLENUM_NUMBER_OF_BITS) {
if(lp[n]!=(LITTLENUM_TYPE)-1)
- break;
+ break;
--n;
tmp_bits-=LITTLENUM_NUMBER_OF_BITS;
}
if(tmp_bits>LITTLENUM_NUMBER_OF_BITS || (lp[n]&mask[tmp_bits])!=mask[tmp_bits]) {
unsigned long carry;
-
+
for (carry = 1; carry && (lp >= words); lp --) {
carry = * lp + carry;
* lp = carry;
}
}
} else if((*lp&mask[prec_bits])!=mask[prec_bits])
- lp++;
+ lp++;
}
-
+
return return_value;
} else if (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;
} else {
word1 |= (exponent_4 << ((LITTLENUM_NUMBER_OF_BITS-1) - exponent_bits))
- | next_bits ((LITTLENUM_NUMBER_OF_BITS-1) - exponent_bits);
+ | next_bits ((LITTLENUM_NUMBER_OF_BITS-1) - exponent_bits);
}
-
+
* lp ++ = word1;
-
+
/* X_PRECISION is special: it has 16 bits of zero in the middle,
followed by a 1 bit. */
if(exponent_bits==15 && precision==X_PRECISION) {
*lp++=0;
*lp++= 1<<(LITTLENUM_NUMBER_OF_BITS)|next_bits(LITTLENUM_NUMBER_OF_BITS-1);
}
-
+
/* The rest of the words are just mantissa bits. */
while(lp < words + precision)
- *lp++ = next_bits (LITTLENUM_NUMBER_OF_BITS);
-
+ *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?
- */
-
-
-/* #if (sizeof(carry)) < ((sizeof(bits[0]) * BITS_PER_CHAR) + 2)
- Please allow at least 1 more bit in carry than is in a LITTLENUM.
- We need that extra bit to hold a carry during a LITTLENUM carry
- propagation. Another extra bit (kept 0) will assure us that we
- don't get a sticky sign bit after shifting right, and that
- permits us to propagate the carry without any masking of bits.
-#endif */
+ /*
+ * 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.
+ We need that extra bit to hold a carry during a LITTLENUM carry
+ propagation. Another extra bit (kept 0) will assure us that we
+ 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 --) {
carry = * lp + carry;
* lp = carry;
/* 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)
- */
+ */
void
-int_to_gen(x)
+ 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?)");
+ as_bad("Error converting number to floating point (Exponent overflow?)");
}
#ifdef TEST
char *
-print_gen(gen)
+ print_gen(gen)
FLONUM_TYPE *gen;
{
FLONUM_TYPE f;
double dv;
float fv;
static char sbuf[40];
-
+
if(gen) {
f=generic_floating_point_number;
generic_floating_point_number= *gen;
bcopy(&arr[0],&fv,sizeof(float));
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
+
+/* end of atof-ieee.c */
projects / deliverable / binutils-gdb.git / blobdiff