1 /* Floating point routines for GDB, the GNU debugger.
3 Copyright (C) 2017-2022 Free Software Foundation, Inc.
5 This file is part of GDB.
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3 of the License, or
10 (at your option) any later version.
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program. If not, see <http://www.gnu.org/licenses/>. */
22 #include "floatformat.h"
23 #include "target-float.h"
26 /* Target floating-point operations.
28 We provide multiple implementations of those operations, which differ
29 by the host-side intermediate format they perform computations in.
31 Those multiple implementations all derive from the following abstract
32 base class, which specifies the set of operations to be implemented. */
34 class target_float_ops
37 virtual std::string
to_string (const gdb_byte
*addr
, const struct type
*type
,
38 const char *format
) const = 0;
39 virtual bool from_string (gdb_byte
*addr
, const struct type
*type
,
40 const std::string
&string
) const = 0;
42 virtual LONGEST
to_longest (const gdb_byte
*addr
,
43 const struct type
*type
) const = 0;
44 virtual void from_longest (gdb_byte
*addr
, const struct type
*type
,
45 LONGEST val
) const = 0;
46 virtual void from_ulongest (gdb_byte
*addr
, const struct type
*type
,
47 ULONGEST val
) const = 0;
48 virtual double to_host_double (const gdb_byte
*addr
,
49 const struct type
*type
) const = 0;
50 virtual void from_host_double (gdb_byte
*addr
, const struct type
*type
,
51 double val
) const = 0;
52 virtual void convert (const gdb_byte
*from
, const struct type
*from_type
,
53 gdb_byte
*to
, const struct type
*to_type
) const = 0;
55 virtual void binop (enum exp_opcode opcode
,
56 const gdb_byte
*x
, const struct type
*type_x
,
57 const gdb_byte
*y
, const struct type
*type_y
,
58 gdb_byte
*res
, const struct type
*type_res
) const = 0;
59 virtual int compare (const gdb_byte
*x
, const struct type
*type_x
,
60 const gdb_byte
*y
, const struct type
*type_y
) const = 0;
64 /* Helper routines operating on binary floating-point data. */
69 /* Different kinds of floatformat numbers recognized by
70 floatformat_classify. To avoid portability issues, we use local
71 values instead of the C99 macros (FP_NAN et cetera). */
80 /* The odds that CHAR_BIT will be anything but 8 are low enough that I'm not
81 going to bother with trying to muck around with whether it is defined in
82 a system header, what we do if not, etc. */
83 #define FLOATFORMAT_CHAR_BIT 8
85 /* The number of bytes that the largest floating-point type that we
86 can convert to doublest will need. */
87 #define FLOATFORMAT_LARGEST_BYTES 16
89 /* Return the floatformat's total size in host bytes. */
91 floatformat_totalsize_bytes (const struct floatformat
*fmt
)
93 return ((fmt
->totalsize
+ FLOATFORMAT_CHAR_BIT
- 1)
94 / FLOATFORMAT_CHAR_BIT
);
97 /* Return the precision of the floating point format FMT. */
99 floatformat_precision (const struct floatformat
*fmt
)
101 /* Assume the precision of and IBM long double is twice the precision
102 of the underlying double. This matches what GCC does. */
104 return 2 * floatformat_precision (fmt
->split_half
);
106 /* Otherwise, the precision is the size of mantissa in bits,
107 including the implicit bit if present. */
108 int prec
= fmt
->man_len
;
109 if (fmt
->intbit
== floatformat_intbit_no
)
115 /* Normalize the byte order of FROM into TO. If no normalization is
116 needed then FMT->byteorder is returned and TO is not changed;
117 otherwise the format of the normalized form in TO is returned. */
118 static enum floatformat_byteorders
119 floatformat_normalize_byteorder (const struct floatformat
*fmt
,
120 const void *from
, void *to
)
122 const unsigned char *swapin
;
123 unsigned char *swapout
;
126 if (fmt
->byteorder
== floatformat_little
127 || fmt
->byteorder
== floatformat_big
)
128 return fmt
->byteorder
;
130 words
= fmt
->totalsize
/ FLOATFORMAT_CHAR_BIT
;
133 swapout
= (unsigned char *)to
;
134 swapin
= (const unsigned char *)from
;
136 if (fmt
->byteorder
== floatformat_vax
)
140 *swapout
++ = swapin
[1];
141 *swapout
++ = swapin
[0];
142 *swapout
++ = swapin
[3];
143 *swapout
++ = swapin
[2];
146 /* This may look weird, since VAX is little-endian, but it is
147 easier to translate to big-endian than to little-endian. */
148 return floatformat_big
;
152 gdb_assert (fmt
->byteorder
== floatformat_littlebyte_bigword
);
156 *swapout
++ = swapin
[3];
157 *swapout
++ = swapin
[2];
158 *swapout
++ = swapin
[1];
159 *swapout
++ = swapin
[0];
162 return floatformat_big
;
166 /* Extract a field which starts at START and is LEN bytes long. DATA and
167 TOTAL_LEN are the thing we are extracting it from, in byteorder ORDER. */
169 get_field (const bfd_byte
*data
, enum floatformat_byteorders order
,
170 unsigned int total_len
, unsigned int start
, unsigned int len
)
172 unsigned long result
;
173 unsigned int cur_byte
;
176 /* Caller must byte-swap words before calling this routine. */
177 gdb_assert (order
== floatformat_little
|| order
== floatformat_big
);
179 /* Start at the least significant part of the field. */
180 if (order
== floatformat_little
)
182 /* We start counting from the other end (i.e, from the high bytes
183 rather than the low bytes). As such, we need to be concerned
184 with what happens if bit 0 doesn't start on a byte boundary.
185 I.e, we need to properly handle the case where total_len is
186 not evenly divisible by 8. So we compute ``excess'' which
187 represents the number of bits from the end of our starting
188 byte needed to get to bit 0. */
189 int excess
= FLOATFORMAT_CHAR_BIT
- (total_len
% FLOATFORMAT_CHAR_BIT
);
191 cur_byte
= (total_len
/ FLOATFORMAT_CHAR_BIT
)
192 - ((start
+ len
+ excess
) / FLOATFORMAT_CHAR_BIT
);
193 cur_bitshift
= ((start
+ len
+ excess
) % FLOATFORMAT_CHAR_BIT
)
194 - FLOATFORMAT_CHAR_BIT
;
198 cur_byte
= (start
+ len
) / FLOATFORMAT_CHAR_BIT
;
200 ((start
+ len
) % FLOATFORMAT_CHAR_BIT
) - FLOATFORMAT_CHAR_BIT
;
202 if (cur_bitshift
> -FLOATFORMAT_CHAR_BIT
)
203 result
= *(data
+ cur_byte
) >> (-cur_bitshift
);
206 cur_bitshift
+= FLOATFORMAT_CHAR_BIT
;
207 if (order
== floatformat_little
)
212 /* Move towards the most significant part of the field. */
213 while (cur_bitshift
< len
)
215 result
|= (unsigned long)*(data
+ cur_byte
) << cur_bitshift
;
216 cur_bitshift
+= FLOATFORMAT_CHAR_BIT
;
219 case floatformat_little
:
222 case floatformat_big
:
227 if (len
< sizeof(result
) * FLOATFORMAT_CHAR_BIT
)
228 /* Mask out bits which are not part of the field. */
229 result
&= ((1UL << len
) - 1);
233 /* Set a field which starts at START and is LEN bytes long. DATA and
234 TOTAL_LEN are the thing we are extracting it from, in byteorder ORDER. */
236 put_field (unsigned char *data
, enum floatformat_byteorders order
,
237 unsigned int total_len
, unsigned int start
, unsigned int len
,
238 unsigned long stuff_to_put
)
240 unsigned int cur_byte
;
243 /* Caller must byte-swap words before calling this routine. */
244 gdb_assert (order
== floatformat_little
|| order
== floatformat_big
);
246 /* Start at the least significant part of the field. */
247 if (order
== floatformat_little
)
249 int excess
= FLOATFORMAT_CHAR_BIT
- (total_len
% FLOATFORMAT_CHAR_BIT
);
251 cur_byte
= (total_len
/ FLOATFORMAT_CHAR_BIT
)
252 - ((start
+ len
+ excess
) / FLOATFORMAT_CHAR_BIT
);
253 cur_bitshift
= ((start
+ len
+ excess
) % FLOATFORMAT_CHAR_BIT
)
254 - FLOATFORMAT_CHAR_BIT
;
258 cur_byte
= (start
+ len
) / FLOATFORMAT_CHAR_BIT
;
260 ((start
+ len
) % FLOATFORMAT_CHAR_BIT
) - FLOATFORMAT_CHAR_BIT
;
262 if (cur_bitshift
> -FLOATFORMAT_CHAR_BIT
)
264 *(data
+ cur_byte
) &=
265 ~(((1 << ((start
+ len
) % FLOATFORMAT_CHAR_BIT
)) - 1)
267 *(data
+ cur_byte
) |=
268 (stuff_to_put
& ((1 << FLOATFORMAT_CHAR_BIT
) - 1)) << (-cur_bitshift
);
270 cur_bitshift
+= FLOATFORMAT_CHAR_BIT
;
271 if (order
== floatformat_little
)
276 /* Move towards the most significant part of the field. */
277 while (cur_bitshift
< len
)
279 if (len
- cur_bitshift
< FLOATFORMAT_CHAR_BIT
)
281 /* This is the last byte. */
282 *(data
+ cur_byte
) &=
283 ~((1 << (len
- cur_bitshift
)) - 1);
284 *(data
+ cur_byte
) |= (stuff_to_put
>> cur_bitshift
);
287 *(data
+ cur_byte
) = ((stuff_to_put
>> cur_bitshift
)
288 & ((1 << FLOATFORMAT_CHAR_BIT
) - 1));
289 cur_bitshift
+= FLOATFORMAT_CHAR_BIT
;
290 if (order
== floatformat_little
)
297 /* Check if VAL (which is assumed to be a floating point number whose
298 format is described by FMT) is negative. */
300 floatformat_is_negative (const struct floatformat
*fmt
,
301 const bfd_byte
*uval
)
303 enum floatformat_byteorders order
;
304 unsigned char newfrom
[FLOATFORMAT_LARGEST_BYTES
];
306 gdb_assert (fmt
!= NULL
);
307 gdb_assert (fmt
->totalsize
308 <= FLOATFORMAT_LARGEST_BYTES
* FLOATFORMAT_CHAR_BIT
);
310 /* An IBM long double (a two element array of double) always takes the
311 sign of the first double. */
313 fmt
= fmt
->split_half
;
315 order
= floatformat_normalize_byteorder (fmt
, uval
, newfrom
);
317 if (order
!= fmt
->byteorder
)
320 return get_field (uval
, order
, fmt
->totalsize
, fmt
->sign_start
, 1);
323 /* Check if VAL is "not a number" (NaN) for FMT. */
324 static enum float_kind
325 floatformat_classify (const struct floatformat
*fmt
,
326 const bfd_byte
*uval
)
330 unsigned int mant_bits
, mant_off
;
332 enum floatformat_byteorders order
;
333 unsigned char newfrom
[FLOATFORMAT_LARGEST_BYTES
];
336 gdb_assert (fmt
!= NULL
);
337 gdb_assert (fmt
->totalsize
338 <= FLOATFORMAT_LARGEST_BYTES
* FLOATFORMAT_CHAR_BIT
);
340 /* An IBM long double (a two element array of double) can be classified
341 by looking at the first double. inf and nan are specified as
342 ignoring the second double. zero and subnormal will always have
343 the second double 0.0 if the long double is correctly rounded. */
345 fmt
= fmt
->split_half
;
347 order
= floatformat_normalize_byteorder (fmt
, uval
, newfrom
);
349 if (order
!= fmt
->byteorder
)
352 exponent
= get_field (uval
, order
, fmt
->totalsize
, fmt
->exp_start
,
355 mant_bits_left
= fmt
->man_len
;
356 mant_off
= fmt
->man_start
;
359 while (mant_bits_left
> 0)
361 mant_bits
= std::min (mant_bits_left
, 32);
363 mant
= get_field (uval
, order
, fmt
->totalsize
, mant_off
, mant_bits
);
365 /* If there is an explicit integer bit, mask it off. */
366 if (mant_off
== fmt
->man_start
367 && fmt
->intbit
== floatformat_intbit_yes
)
368 mant
&= ~(1 << (mant_bits
- 1));
376 mant_off
+= mant_bits
;
377 mant_bits_left
-= mant_bits
;
380 /* If exp_nan is not set, assume that inf, NaN, and subnormals are not
395 return float_subnormal
;
398 if (exponent
== fmt
->exp_nan
)
401 return float_infinite
;
409 /* Convert the mantissa of VAL (which is assumed to be a floating
410 point number whose format is described by FMT) into a hexadecimal
411 and store it in a static string. Return a pointer to that string. */
413 floatformat_mantissa (const struct floatformat
*fmt
,
416 unsigned char *uval
= (unsigned char *) val
;
418 unsigned int mant_bits
, mant_off
;
423 enum floatformat_byteorders order
;
424 unsigned char newfrom
[FLOATFORMAT_LARGEST_BYTES
];
426 gdb_assert (fmt
!= NULL
);
427 gdb_assert (fmt
->totalsize
428 <= FLOATFORMAT_LARGEST_BYTES
* FLOATFORMAT_CHAR_BIT
);
430 /* For IBM long double (a two element array of double), return the
431 mantissa of the first double. The problem with returning the
432 actual mantissa from both doubles is that there can be an
433 arbitrary number of implied 0's or 1's between the mantissas
434 of the first and second double. In any case, this function
435 is only used for dumping out nans, and a nan is specified to
436 ignore the value in the second double. */
438 fmt
= fmt
->split_half
;
440 order
= floatformat_normalize_byteorder (fmt
, uval
, newfrom
);
442 if (order
!= fmt
->byteorder
)
448 /* Make sure we have enough room to store the mantissa. */
449 gdb_assert (sizeof res
> ((fmt
->man_len
+ 7) / 8) * 2);
451 mant_off
= fmt
->man_start
;
452 mant_bits_left
= fmt
->man_len
;
453 mant_bits
= (mant_bits_left
% 32) > 0 ? mant_bits_left
% 32 : 32;
455 mant
= get_field (uval
, order
, fmt
->totalsize
, mant_off
, mant_bits
);
457 len
= xsnprintf (res
, sizeof res
, "%lx", mant
);
459 mant_off
+= mant_bits
;
460 mant_bits_left
-= mant_bits
;
462 while (mant_bits_left
> 0)
464 mant
= get_field (uval
, order
, fmt
->totalsize
, mant_off
, 32);
466 xsnprintf (buf
, sizeof buf
, "%08lx", mant
);
467 gdb_assert (len
+ strlen (buf
) <= sizeof res
);
471 mant_bits_left
-= 32;
477 /* Convert printf format string FORMAT to the otherwise equivalent string
478 which may be used to print a host floating-point number using the length
479 modifier LENGTH (which may be 0 if none is needed). If FORMAT is null,
480 return a format appropriate to print the full precision of a target
481 floating-point number of format FMT. */
483 floatformat_printf_format (const struct floatformat
*fmt
,
484 const char *format
, char length
)
486 std::string host_format
;
489 if (format
== nullptr)
491 /* If no format was specified, print the number using a format string
492 where the precision is set to the DECIMAL_DIG value for the given
493 floating-point format. This value is computed as
495 ceil(1 + p * log10(b)),
497 where p is the precision of the floating-point format in bits, and
498 b is the base (which is always 2 for the formats we support). */
499 const double log10_2
= .30102999566398119521;
500 double d_decimal_dig
= 1 + floatformat_precision (fmt
) * log10_2
;
501 int decimal_dig
= d_decimal_dig
;
502 if (decimal_dig
< d_decimal_dig
)
505 host_format
= string_printf ("%%.%d", decimal_dig
);
510 /* Use the specified format, stripping out the conversion character
511 and length modifier, if present. */
512 size_t len
= strlen (format
);
513 gdb_assert (len
> 1);
514 conversion
= format
[--len
];
515 gdb_assert (conversion
== 'e' || conversion
== 'f' || conversion
== 'g'
516 || conversion
== 'E' || conversion
== 'G');
517 if (format
[len
- 1] == 'L')
520 host_format
= std::string (format
, len
);
523 /* Add the length modifier and conversion character appropriate for
524 handling the appropriate host floating-point type. */
526 host_format
+= length
;
527 host_format
+= conversion
;
532 /* Implementation of target_float_ops using the host floating-point type T
533 as intermediate type. */
535 template<typename T
> class host_float_ops
: public target_float_ops
538 std::string
to_string (const gdb_byte
*addr
, const struct type
*type
,
539 const char *format
) const override
;
540 bool from_string (gdb_byte
*addr
, const struct type
*type
,
541 const std::string
&string
) const override
;
543 LONGEST
to_longest (const gdb_byte
*addr
,
544 const struct type
*type
) const override
;
545 void from_longest (gdb_byte
*addr
, const struct type
*type
,
546 LONGEST val
) const override
;
547 void from_ulongest (gdb_byte
*addr
, const struct type
*type
,
548 ULONGEST val
) const override
;
549 double to_host_double (const gdb_byte
*addr
,
550 const struct type
*type
) const override
;
551 void from_host_double (gdb_byte
*addr
, const struct type
*type
,
552 double val
) const override
;
553 void convert (const gdb_byte
*from
, const struct type
*from_type
,
554 gdb_byte
*to
, const struct type
*to_type
) const override
;
556 void binop (enum exp_opcode opcode
,
557 const gdb_byte
*x
, const struct type
*type_x
,
558 const gdb_byte
*y
, const struct type
*type_y
,
559 gdb_byte
*res
, const struct type
*type_res
) const override
;
560 int compare (const gdb_byte
*x
, const struct type
*type_x
,
561 const gdb_byte
*y
, const struct type
*type_y
) const override
;
564 void from_target (const struct floatformat
*fmt
,
565 const gdb_byte
*from
, T
*to
) const;
566 void from_target (const struct type
*type
,
567 const gdb_byte
*from
, T
*to
) const;
569 void to_target (const struct type
*type
,
570 const T
*from
, gdb_byte
*to
) const;
571 void to_target (const struct floatformat
*fmt
,
572 const T
*from
, gdb_byte
*to
) const;
576 /* Convert TO/FROM target to the host floating-point format T.
578 If the host and target formats agree, we just copy the raw data
579 into the appropriate type of variable and return, letting the host
580 increase precision as necessary. Otherwise, we call the conversion
581 routine and let it do the dirty work. Note that even if the target
582 and host floating-point formats match, the length of the types
583 might still be different, so the conversion routines must make sure
584 to not overrun any buffers. For example, on x86, long double is
585 the 80-bit extended precision type on both 32-bit and 64-bit ABIs,
586 but by default it is stored as 12 bytes on 32-bit, and 16 bytes on
587 64-bit, for alignment reasons. See comment in store_typed_floating
588 for a discussion about zeroing out remaining bytes in the target
591 static const struct floatformat
*host_float_format
= GDB_HOST_FLOAT_FORMAT
;
592 static const struct floatformat
*host_double_format
= GDB_HOST_DOUBLE_FORMAT
;
593 static const struct floatformat
*host_long_double_format
594 = GDB_HOST_LONG_DOUBLE_FORMAT
;
596 /* Convert target floating-point value at FROM in format FMT to host
597 floating-point format of type T. */
598 template<typename T
> void
599 host_float_ops
<T
>::from_target (const struct floatformat
*fmt
,
600 const gdb_byte
*from
, T
*to
) const
602 gdb_assert (fmt
!= NULL
);
604 if (fmt
== host_float_format
)
608 memcpy (&val
, from
, floatformat_totalsize_bytes (fmt
));
612 else if (fmt
== host_double_format
)
616 memcpy (&val
, from
, floatformat_totalsize_bytes (fmt
));
620 else if (fmt
== host_long_double_format
)
624 memcpy (&val
, from
, floatformat_totalsize_bytes (fmt
));
629 unsigned char *ufrom
= (unsigned char *) from
;
632 unsigned int mant_bits
, mant_off
;
634 int special_exponent
; /* It's a NaN, denorm or zero. */
635 enum floatformat_byteorders order
;
636 unsigned char newfrom
[FLOATFORMAT_LARGEST_BYTES
];
637 enum float_kind kind
;
639 gdb_assert (fmt
->totalsize
640 <= FLOATFORMAT_LARGEST_BYTES
* FLOATFORMAT_CHAR_BIT
);
642 /* For non-numbers, reuse libiberty's logic to find the correct
643 format. We do not lose any precision in this case by passing
645 kind
= floatformat_classify (fmt
, (const bfd_byte
*) from
);
646 if (kind
== float_infinite
|| kind
== float_nan
)
650 floatformat_to_double
/* ARI: floatformat_to_double */
651 (fmt
->split_half
? fmt
->split_half
: fmt
, from
, &dto
);
656 order
= floatformat_normalize_byteorder (fmt
, ufrom
, newfrom
);
658 if (order
!= fmt
->byteorder
)
665 from_target (fmt
->split_half
, ufrom
, &dtop
);
666 /* Preserve the sign of 0, which is the sign of the top
673 from_target (fmt
->split_half
,
674 ufrom
+ fmt
->totalsize
/ FLOATFORMAT_CHAR_BIT
/ 2, &dbot
);
679 exponent
= get_field (ufrom
, order
, fmt
->totalsize
, fmt
->exp_start
,
681 /* Note that if exponent indicates a NaN, we can't really do anything useful
682 (not knowing if the host has NaN's, or how to build one). So it will
683 end up as an infinity or something close; that is OK. */
685 mant_bits_left
= fmt
->man_len
;
686 mant_off
= fmt
->man_start
;
689 special_exponent
= exponent
== 0 || exponent
== fmt
->exp_nan
;
691 /* Don't bias NaNs. Use minimum exponent for denorms. For
692 simplicity, we don't check for zero as the exponent doesn't matter.
693 Note the cast to int; exp_bias is unsigned, so it's important to
694 make sure the operation is done in signed arithmetic. */
695 if (!special_exponent
)
696 exponent
-= fmt
->exp_bias
;
697 else if (exponent
== 0)
698 exponent
= 1 - fmt
->exp_bias
;
700 /* Build the result algebraically. Might go infinite, underflow, etc;
703 /* If this format uses a hidden bit, explicitly add it in now. Otherwise,
704 increment the exponent by one to account for the integer bit. */
706 if (!special_exponent
)
708 if (fmt
->intbit
== floatformat_intbit_no
)
709 dto
= ldexp (1.0, exponent
);
714 while (mant_bits_left
> 0)
716 mant_bits
= std::min (mant_bits_left
, 32);
718 mant
= get_field (ufrom
, order
, fmt
->totalsize
, mant_off
, mant_bits
);
720 dto
+= ldexp ((T
) mant
, exponent
- mant_bits
);
721 exponent
-= mant_bits
;
722 mant_off
+= mant_bits
;
723 mant_bits_left
-= mant_bits
;
726 /* Negate it if negative. */
727 if (get_field (ufrom
, order
, fmt
->totalsize
, fmt
->sign_start
, 1))
732 template<typename T
> void
733 host_float_ops
<T
>::from_target (const struct type
*type
,
734 const gdb_byte
*from
, T
*to
) const
736 from_target (floatformat_from_type (type
), from
, to
);
739 /* Convert host floating-point value of type T to target floating-point
740 value in format FMT and store at TO. */
741 template<typename T
> void
742 host_float_ops
<T
>::to_target (const struct floatformat
*fmt
,
743 const T
*from
, gdb_byte
*to
) const
745 gdb_assert (fmt
!= NULL
);
747 if (fmt
== host_float_format
)
751 memcpy (to
, &val
, floatformat_totalsize_bytes (fmt
));
754 else if (fmt
== host_double_format
)
758 memcpy (to
, &val
, floatformat_totalsize_bytes (fmt
));
761 else if (fmt
== host_long_double_format
)
763 long double val
= *from
;
765 memcpy (to
, &val
, floatformat_totalsize_bytes (fmt
));
772 unsigned int mant_bits
, mant_off
;
774 unsigned char *uto
= (unsigned char *) to
;
775 enum floatformat_byteorders order
= fmt
->byteorder
;
776 unsigned char newto
[FLOATFORMAT_LARGEST_BYTES
];
778 if (order
!= floatformat_little
)
779 order
= floatformat_big
;
781 if (order
!= fmt
->byteorder
)
784 memcpy (&dfrom
, from
, sizeof (dfrom
));
785 memset (uto
, 0, floatformat_totalsize_bytes (fmt
));
789 /* Use static volatile to ensure that any excess precision is
790 removed via storing in memory, and so the top half really is
791 the result of converting to double. */
792 static volatile double dtop
, dbot
;
795 dtop
= (double) dfrom
;
796 /* If the rounded top half is Inf, the bottom must be 0 not NaN
798 if (dtop
+ dtop
== dtop
&& dtop
!= 0.0)
801 dbot
= (double) (dfrom
- (T
) dtop
);
804 to_target (fmt
->split_half
, &dtopnv
, uto
);
805 to_target (fmt
->split_half
, &dbotnv
,
806 uto
+ fmt
->totalsize
/ FLOATFORMAT_CHAR_BIT
/ 2);
811 goto finalize_byteorder
; /* Result is zero */
812 if (dfrom
!= dfrom
) /* Result is NaN */
815 put_field (uto
, order
, fmt
->totalsize
, fmt
->exp_start
,
816 fmt
->exp_len
, fmt
->exp_nan
);
817 /* Be sure it's not infinity, but NaN value is irrel. */
818 put_field (uto
, order
, fmt
->totalsize
, fmt
->man_start
,
820 goto finalize_byteorder
;
823 /* If negative, set the sign bit. */
826 put_field (uto
, order
, fmt
->totalsize
, fmt
->sign_start
, 1, 1);
830 if (dfrom
+ dfrom
== dfrom
&& dfrom
!= 0.0) /* Result is Infinity. */
832 /* Infinity exponent is same as NaN's. */
833 put_field (uto
, order
, fmt
->totalsize
, fmt
->exp_start
,
834 fmt
->exp_len
, fmt
->exp_nan
);
835 /* Infinity mantissa is all zeroes. */
836 put_field (uto
, order
, fmt
->totalsize
, fmt
->man_start
,
838 goto finalize_byteorder
;
841 mant
= frexp (dfrom
, &exponent
);
843 if (exponent
+ fmt
->exp_bias
<= 0)
845 /* The value is too small to be expressed in the destination
846 type (not enough bits in the exponent. Treat as 0. */
847 put_field (uto
, order
, fmt
->totalsize
, fmt
->exp_start
,
849 put_field (uto
, order
, fmt
->totalsize
, fmt
->man_start
,
851 goto finalize_byteorder
;
854 if (exponent
+ fmt
->exp_bias
>= (1 << fmt
->exp_len
))
856 /* The value is too large to fit into the destination.
857 Treat as infinity. */
858 put_field (uto
, order
, fmt
->totalsize
, fmt
->exp_start
,
859 fmt
->exp_len
, fmt
->exp_nan
);
860 put_field (uto
, order
, fmt
->totalsize
, fmt
->man_start
,
862 goto finalize_byteorder
;
865 put_field (uto
, order
, fmt
->totalsize
, fmt
->exp_start
, fmt
->exp_len
,
866 exponent
+ fmt
->exp_bias
- 1);
868 mant_bits_left
= fmt
->man_len
;
869 mant_off
= fmt
->man_start
;
870 while (mant_bits_left
> 0)
872 unsigned long mant_long
;
874 mant_bits
= mant_bits_left
< 32 ? mant_bits_left
: 32;
876 mant
*= 4294967296.0;
877 mant_long
= ((unsigned long) mant
) & 0xffffffffL
;
880 /* If the integer bit is implicit, then we need to discard it.
881 If we are discarding a zero, we should be (but are not) creating
882 a denormalized number which means adjusting the exponent
884 if (mant_bits_left
== fmt
->man_len
885 && fmt
->intbit
== floatformat_intbit_no
)
888 mant_long
&= 0xffffffffL
;
889 /* If we are processing the top 32 mantissa bits of a doublest
890 so as to convert to a float value with implied integer bit,
891 we will only be putting 31 of those 32 bits into the
892 final value due to the discarding of the top bit. In the
893 case of a small float value where the number of mantissa
894 bits is less than 32, discarding the top bit does not alter
895 the number of bits we will be adding to the result. */
902 /* The bits we want are in the most significant MANT_BITS bits of
903 mant_long. Move them to the least significant. */
904 mant_long
>>= 32 - mant_bits
;
907 put_field (uto
, order
, fmt
->totalsize
,
908 mant_off
, mant_bits
, mant_long
);
909 mant_off
+= mant_bits
;
910 mant_bits_left
-= mant_bits
;
914 /* Do we need to byte-swap the words in the result? */
915 if (order
!= fmt
->byteorder
)
916 floatformat_normalize_byteorder (fmt
, newto
, to
);
919 template<typename T
> void
920 host_float_ops
<T
>::to_target (const struct type
*type
,
921 const T
*from
, gdb_byte
*to
) const
923 /* Ensure possible padding bytes in the target buffer are zeroed out. */
924 memset (to
, 0, type
->length ());
926 to_target (floatformat_from_type (type
), from
, to
);
929 /* Convert the byte-stream ADDR, interpreted as floating-point type TYPE,
930 to a string, optionally using the print format FORMAT. */
931 template<typename T
> struct printf_length_modifier
933 static constexpr char value
= 0;
935 template<> struct printf_length_modifier
<long double>
937 static constexpr char value
= 'L';
939 template<typename T
> std::string
940 host_float_ops
<T
>::to_string (const gdb_byte
*addr
, const struct type
*type
,
941 const char *format
) const
943 /* Determine the format string to use on the host side. */
944 constexpr char length
= printf_length_modifier
<T
>::value
;
945 const struct floatformat
*fmt
= floatformat_from_type (type
);
946 std::string host_format
= floatformat_printf_format (fmt
, format
, length
);
949 from_target (type
, addr
, &host_float
);
952 DIAGNOSTIC_IGNORE_FORMAT_NONLITERAL
953 return string_printf (host_format
.c_str (), host_float
);
957 /* Parse string IN into a target floating-number of type TYPE and
958 store it as byte-stream ADDR. Return whether parsing succeeded. */
959 template<typename T
> struct scanf_length_modifier
961 static constexpr char value
= 0;
963 template<> struct scanf_length_modifier
<double>
965 static constexpr char value
= 'l';
967 template<> struct scanf_length_modifier
<long double>
969 static constexpr char value
= 'L';
971 template<typename T
> bool
972 host_float_ops
<T
>::from_string (gdb_byte
*addr
, const struct type
*type
,
973 const std::string
&in
) const
978 std::string scan_format
= "%";
979 if (scanf_length_modifier
<T
>::value
)
980 scan_format
+= scanf_length_modifier
<T
>::value
;
981 scan_format
+= "g%n";
984 DIAGNOSTIC_IGNORE_FORMAT_NONLITERAL
985 num
= sscanf (in
.c_str (), scan_format
.c_str(), &host_float
, &n
);
988 /* The sscanf man page suggests not making any assumptions on the effect
989 of %n on the result, so we don't.
990 That is why we simply test num == 0. */
994 /* We only accept the whole string. */
998 to_target (type
, &host_float
, addr
);
1002 /* Convert the byte-stream ADDR, interpreted as floating-point type TYPE,
1003 to an integer value (rounding towards zero). */
1004 template<typename T
> LONGEST
1005 host_float_ops
<T
>::to_longest (const gdb_byte
*addr
,
1006 const struct type
*type
) const
1009 from_target (type
, addr
, &host_float
);
1010 T min_possible_range
= static_cast<T
>(std::numeric_limits
<LONGEST
>::min());
1011 T max_possible_range
= -min_possible_range
;
1012 /* host_float can be converted to an integer as long as it's in
1013 the range [min_possible_range, max_possible_range). If not, it is either
1014 too large, or too small, or is NaN; in this case return the maximum or
1015 minimum possible value. */
1016 if (host_float
< max_possible_range
&& host_float
>= min_possible_range
)
1017 return static_cast<LONGEST
> (host_float
);
1018 if (host_float
< min_possible_range
)
1019 return std::numeric_limits
<LONGEST
>::min();
1020 /* This line will be executed if host_float is NaN. */
1021 return std::numeric_limits
<LONGEST
>::max();
1024 /* Convert signed integer VAL to a target floating-number of type TYPE
1025 and store it as byte-stream ADDR. */
1026 template<typename T
> void
1027 host_float_ops
<T
>::from_longest (gdb_byte
*addr
, const struct type
*type
,
1030 T host_float
= (T
) val
;
1031 to_target (type
, &host_float
, addr
);
1034 /* Convert unsigned integer VAL to a target floating-number of type TYPE
1035 and store it as byte-stream ADDR. */
1036 template<typename T
> void
1037 host_float_ops
<T
>::from_ulongest (gdb_byte
*addr
, const struct type
*type
,
1040 T host_float
= (T
) val
;
1041 to_target (type
, &host_float
, addr
);
1044 /* Convert the byte-stream ADDR, interpreted as floating-point type TYPE,
1045 to a floating-point value in the host "double" format. */
1046 template<typename T
> double
1047 host_float_ops
<T
>::to_host_double (const gdb_byte
*addr
,
1048 const struct type
*type
) const
1051 from_target (type
, addr
, &host_float
);
1052 return (double) host_float
;
1055 /* Convert floating-point value VAL in the host "double" format to a target
1056 floating-number of type TYPE and store it as byte-stream ADDR. */
1057 template<typename T
> void
1058 host_float_ops
<T
>::from_host_double (gdb_byte
*addr
, const struct type
*type
,
1061 T host_float
= (T
) val
;
1062 to_target (type
, &host_float
, addr
);
1065 /* Convert a floating-point number of type FROM_TYPE from the target
1066 byte-stream FROM to a floating-point number of type TO_TYPE, and
1067 store it to the target byte-stream TO. */
1068 template<typename T
> void
1069 host_float_ops
<T
>::convert (const gdb_byte
*from
,
1070 const struct type
*from_type
,
1072 const struct type
*to_type
) const
1075 from_target (from_type
, from
, &host_float
);
1076 to_target (to_type
, &host_float
, to
);
1079 /* Perform the binary operation indicated by OPCODE, using as operands the
1080 target byte streams X and Y, interpreted as floating-point numbers of
1081 types TYPE_X and TYPE_Y, respectively. Convert the result to format
1082 TYPE_RES and store it into the byte-stream RES. */
1083 template<typename T
> void
1084 host_float_ops
<T
>::binop (enum exp_opcode op
,
1085 const gdb_byte
*x
, const struct type
*type_x
,
1086 const gdb_byte
*y
, const struct type
*type_y
,
1087 gdb_byte
*res
, const struct type
*type_res
) const
1091 from_target (type_x
, x
, &v1
);
1092 from_target (type_y
, y
, &v2
);
1116 error (_("Cannot perform exponentiation: %s"),
1117 safe_strerror (errno
));
1121 v
= v1
< v2
? v1
: v2
;
1125 v
= v1
> v2
? v1
: v2
;
1129 error (_("Integer-only operation on floating point number."));
1133 to_target (type_res
, &v
, res
);
1136 /* Compare the two target byte streams X and Y, interpreted as floating-point
1137 numbers of types TYPE_X and TYPE_Y, respectively. Return zero if X and Y
1138 are equal, -1 if X is less than Y, and 1 otherwise. */
1139 template<typename T
> int
1140 host_float_ops
<T
>::compare (const gdb_byte
*x
, const struct type
*type_x
,
1141 const gdb_byte
*y
, const struct type
*type_y
) const
1145 from_target (type_x
, x
, &v1
);
1146 from_target (type_y
, y
, &v2
);
1156 /* Implementation of target_float_ops using the MPFR library
1157 mpfr_t as intermediate type. */
1161 #define MPFR_USE_INTMAX_T
1165 class mpfr_float_ops
: public target_float_ops
1168 std::string
to_string (const gdb_byte
*addr
, const struct type
*type
,
1169 const char *format
) const override
;
1170 bool from_string (gdb_byte
*addr
, const struct type
*type
,
1171 const std::string
&string
) const override
;
1173 LONGEST
to_longest (const gdb_byte
*addr
,
1174 const struct type
*type
) const override
;
1175 void from_longest (gdb_byte
*addr
, const struct type
*type
,
1176 LONGEST val
) const override
;
1177 void from_ulongest (gdb_byte
*addr
, const struct type
*type
,
1178 ULONGEST val
) const override
;
1179 double to_host_double (const gdb_byte
*addr
,
1180 const struct type
*type
) const override
;
1181 void from_host_double (gdb_byte
*addr
, const struct type
*type
,
1182 double val
) const override
;
1183 void convert (const gdb_byte
*from
, const struct type
*from_type
,
1184 gdb_byte
*to
, const struct type
*to_type
) const override
;
1186 void binop (enum exp_opcode opcode
,
1187 const gdb_byte
*x
, const struct type
*type_x
,
1188 const gdb_byte
*y
, const struct type
*type_y
,
1189 gdb_byte
*res
, const struct type
*type_res
) const override
;
1190 int compare (const gdb_byte
*x
, const struct type
*type_x
,
1191 const gdb_byte
*y
, const struct type
*type_y
) const override
;
1194 /* Local wrapper class to handle mpfr_t initialization and cleanup. */
1200 gdb_mpfr (const struct type
*type
)
1202 const struct floatformat
*fmt
= floatformat_from_type (type
);
1203 mpfr_init2 (val
, floatformat_precision (fmt
));
1206 gdb_mpfr (const gdb_mpfr
&source
)
1208 mpfr_init2 (val
, mpfr_get_prec (source
.val
));
1217 void from_target (const struct floatformat
*fmt
,
1218 const gdb_byte
*from
, gdb_mpfr
&to
) const;
1219 void from_target (const struct type
*type
,
1220 const gdb_byte
*from
, gdb_mpfr
&to
) const;
1222 void to_target (const struct type
*type
,
1223 const gdb_mpfr
&from
, gdb_byte
*to
) const;
1224 void to_target (const struct floatformat
*fmt
,
1225 const gdb_mpfr
&from
, gdb_byte
*to
) const;
1229 /* Convert TO/FROM target floating-point format to mpfr_t. */
1232 mpfr_float_ops::from_target (const struct floatformat
*fmt
,
1233 const gdb_byte
*orig_from
, gdb_mpfr
&to
) const
1235 const gdb_byte
*from
= orig_from
;
1236 mpfr_exp_t exponent
;
1238 unsigned int mant_bits
, mant_off
;
1240 int special_exponent
; /* It's a NaN, denorm or zero. */
1241 enum floatformat_byteorders order
;
1242 unsigned char newfrom
[FLOATFORMAT_LARGEST_BYTES
];
1243 enum float_kind kind
;
1245 gdb_assert (fmt
->totalsize
1246 <= FLOATFORMAT_LARGEST_BYTES
* FLOATFORMAT_CHAR_BIT
);
1248 /* Handle non-numbers. */
1249 kind
= floatformat_classify (fmt
, from
);
1250 if (kind
== float_infinite
)
1252 mpfr_set_inf (to
.val
, floatformat_is_negative (fmt
, from
) ? -1 : 1);
1255 if (kind
== float_nan
)
1257 mpfr_set_nan (to
.val
);
1261 order
= floatformat_normalize_byteorder (fmt
, from
, newfrom
);
1263 if (order
!= fmt
->byteorder
)
1266 if (fmt
->split_half
)
1268 gdb_mpfr
top (to
), bot (to
);
1270 from_target (fmt
->split_half
, from
, top
);
1271 /* Preserve the sign of 0, which is the sign of the top half. */
1272 if (mpfr_zero_p (top
.val
))
1274 mpfr_set (to
.val
, top
.val
, MPFR_RNDN
);
1277 from_target (fmt
->split_half
,
1278 from
+ fmt
->totalsize
/ FLOATFORMAT_CHAR_BIT
/ 2, bot
);
1279 mpfr_add (to
.val
, top
.val
, bot
.val
, MPFR_RNDN
);
1283 exponent
= get_field (from
, order
, fmt
->totalsize
, fmt
->exp_start
,
1285 /* Note that if exponent indicates a NaN, we can't really do anything useful
1286 (not knowing if the host has NaN's, or how to build one). So it will
1287 end up as an infinity or something close; that is OK. */
1289 mant_bits_left
= fmt
->man_len
;
1290 mant_off
= fmt
->man_start
;
1291 mpfr_set_zero (to
.val
, 0);
1293 special_exponent
= exponent
== 0 || exponent
== fmt
->exp_nan
;
1295 /* Don't bias NaNs. Use minimum exponent for denorms. For
1296 simplicity, we don't check for zero as the exponent doesn't matter.
1297 Note the cast to int; exp_bias is unsigned, so it's important to
1298 make sure the operation is done in signed arithmetic. */
1299 if (!special_exponent
)
1300 exponent
-= fmt
->exp_bias
;
1301 else if (exponent
== 0)
1302 exponent
= 1 - fmt
->exp_bias
;
1304 /* Build the result algebraically. Might go infinite, underflow, etc;
1307 /* If this format uses a hidden bit, explicitly add it in now. Otherwise,
1308 increment the exponent by one to account for the integer bit. */
1310 if (!special_exponent
)
1312 if (fmt
->intbit
== floatformat_intbit_no
)
1313 mpfr_set_ui_2exp (to
.val
, 1, exponent
, MPFR_RNDN
);
1320 while (mant_bits_left
> 0)
1322 mant_bits
= std::min (mant_bits_left
, 32);
1324 mant
= get_field (from
, order
, fmt
->totalsize
, mant_off
, mant_bits
);
1326 mpfr_set_ui (tmp
.val
, mant
, MPFR_RNDN
);
1327 mpfr_mul_2si (tmp
.val
, tmp
.val
, exponent
- mant_bits
, MPFR_RNDN
);
1328 mpfr_add (to
.val
, to
.val
, tmp
.val
, MPFR_RNDN
);
1329 exponent
-= mant_bits
;
1330 mant_off
+= mant_bits
;
1331 mant_bits_left
-= mant_bits
;
1334 /* Negate it if negative. */
1335 if (get_field (from
, order
, fmt
->totalsize
, fmt
->sign_start
, 1))
1336 mpfr_neg (to
.val
, to
.val
, MPFR_RNDN
);
1340 mpfr_float_ops::from_target (const struct type
*type
,
1341 const gdb_byte
*from
, gdb_mpfr
&to
) const
1343 from_target (floatformat_from_type (type
), from
, to
);
1347 mpfr_float_ops::to_target (const struct floatformat
*fmt
,
1348 const gdb_mpfr
&from
, gdb_byte
*orig_to
) const
1350 unsigned char *to
= orig_to
;
1351 mpfr_exp_t exponent
;
1352 unsigned int mant_bits
, mant_off
;
1354 enum floatformat_byteorders order
= fmt
->byteorder
;
1355 unsigned char newto
[FLOATFORMAT_LARGEST_BYTES
];
1357 if (order
!= floatformat_little
)
1358 order
= floatformat_big
;
1360 if (order
!= fmt
->byteorder
)
1363 memset (to
, 0, floatformat_totalsize_bytes (fmt
));
1365 if (fmt
->split_half
)
1367 gdb_mpfr
top (from
), bot (from
);
1369 mpfr_set (top
.val
, from
.val
, MPFR_RNDN
);
1370 /* If the rounded top half is Inf, the bottom must be 0 not NaN
1372 if (mpfr_inf_p (top
.val
))
1373 mpfr_set_zero (bot
.val
, 0);
1375 mpfr_sub (bot
.val
, from
.val
, top
.val
, MPFR_RNDN
);
1377 to_target (fmt
->split_half
, top
, to
);
1378 to_target (fmt
->split_half
, bot
,
1379 to
+ fmt
->totalsize
/ FLOATFORMAT_CHAR_BIT
/ 2);
1383 gdb_mpfr
tmp (from
);
1385 if (mpfr_zero_p (from
.val
))
1386 goto finalize_byteorder
; /* Result is zero */
1388 mpfr_set (tmp
.val
, from
.val
, MPFR_RNDN
);
1390 if (mpfr_nan_p (tmp
.val
)) /* Result is NaN */
1393 put_field (to
, order
, fmt
->totalsize
, fmt
->exp_start
,
1394 fmt
->exp_len
, fmt
->exp_nan
);
1395 /* Be sure it's not infinity, but NaN value is irrel. */
1396 put_field (to
, order
, fmt
->totalsize
, fmt
->man_start
,
1398 goto finalize_byteorder
;
1401 /* If negative, set the sign bit. */
1402 if (mpfr_sgn (tmp
.val
) < 0)
1404 put_field (to
, order
, fmt
->totalsize
, fmt
->sign_start
, 1, 1);
1405 mpfr_neg (tmp
.val
, tmp
.val
, MPFR_RNDN
);
1408 if (mpfr_inf_p (tmp
.val
)) /* Result is Infinity. */
1410 /* Infinity exponent is same as NaN's. */
1411 put_field (to
, order
, fmt
->totalsize
, fmt
->exp_start
,
1412 fmt
->exp_len
, fmt
->exp_nan
);
1413 /* Infinity mantissa is all zeroes. */
1414 put_field (to
, order
, fmt
->totalsize
, fmt
->man_start
,
1416 goto finalize_byteorder
;
1419 mpfr_frexp (&exponent
, tmp
.val
, tmp
.val
, MPFR_RNDN
);
1421 if (exponent
+ fmt
->exp_bias
<= 0)
1423 /* The value is too small to be expressed in the destination
1424 type (not enough bits in the exponent. Treat as 0. */
1425 put_field (to
, order
, fmt
->totalsize
, fmt
->exp_start
,
1427 put_field (to
, order
, fmt
->totalsize
, fmt
->man_start
,
1429 goto finalize_byteorder
;
1432 if (exponent
+ fmt
->exp_bias
>= (1 << fmt
->exp_len
))
1434 /* The value is too large to fit into the destination.
1435 Treat as infinity. */
1436 put_field (to
, order
, fmt
->totalsize
, fmt
->exp_start
,
1437 fmt
->exp_len
, fmt
->exp_nan
);
1438 put_field (to
, order
, fmt
->totalsize
, fmt
->man_start
,
1440 goto finalize_byteorder
;
1443 put_field (to
, order
, fmt
->totalsize
, fmt
->exp_start
, fmt
->exp_len
,
1444 exponent
+ fmt
->exp_bias
- 1);
1446 mant_bits_left
= fmt
->man_len
;
1447 mant_off
= fmt
->man_start
;
1448 while (mant_bits_left
> 0)
1450 unsigned long mant_long
;
1452 mant_bits
= mant_bits_left
< 32 ? mant_bits_left
: 32;
1454 mpfr_mul_2ui (tmp
.val
, tmp
.val
, 32, MPFR_RNDN
);
1455 mant_long
= mpfr_get_ui (tmp
.val
, MPFR_RNDZ
) & 0xffffffffL
;
1456 mpfr_sub_ui (tmp
.val
, tmp
.val
, mant_long
, MPFR_RNDZ
);
1458 /* If the integer bit is implicit, then we need to discard it.
1459 If we are discarding a zero, we should be (but are not) creating
1460 a denormalized number which means adjusting the exponent
1462 if (mant_bits_left
== fmt
->man_len
1463 && fmt
->intbit
== floatformat_intbit_no
)
1466 mant_long
&= 0xffffffffL
;
1467 /* If we are processing the top 32 mantissa bits of a doublest
1468 so as to convert to a float value with implied integer bit,
1469 we will only be putting 31 of those 32 bits into the
1470 final value due to the discarding of the top bit. In the
1471 case of a small float value where the number of mantissa
1472 bits is less than 32, discarding the top bit does not alter
1473 the number of bits we will be adding to the result. */
1474 if (mant_bits
== 32)
1480 /* The bits we want are in the most significant MANT_BITS bits of
1481 mant_long. Move them to the least significant. */
1482 mant_long
>>= 32 - mant_bits
;
1485 put_field (to
, order
, fmt
->totalsize
,
1486 mant_off
, mant_bits
, mant_long
);
1487 mant_off
+= mant_bits
;
1488 mant_bits_left
-= mant_bits
;
1492 /* Do we need to byte-swap the words in the result? */
1493 if (order
!= fmt
->byteorder
)
1494 floatformat_normalize_byteorder (fmt
, newto
, orig_to
);
1498 mpfr_float_ops::to_target (const struct type
*type
,
1499 const gdb_mpfr
&from
, gdb_byte
*to
) const
1501 /* Ensure possible padding bytes in the target buffer are zeroed out. */
1502 memset (to
, 0, type
->length ());
1504 to_target (floatformat_from_type (type
), from
, to
);
1507 /* Convert the byte-stream ADDR, interpreted as floating-point type TYPE,
1508 to a string, optionally using the print format FORMAT. */
1510 mpfr_float_ops::to_string (const gdb_byte
*addr
,
1511 const struct type
*type
,
1512 const char *format
) const
1514 const struct floatformat
*fmt
= floatformat_from_type (type
);
1516 /* Unless we need to adhere to a specific format, provide special
1517 output for certain cases. */
1518 if (format
== nullptr)
1520 /* Detect invalid representations. */
1521 if (!floatformat_is_valid (fmt
, addr
))
1522 return "<invalid float value>";
1524 /* Handle NaN and Inf. */
1525 enum float_kind kind
= floatformat_classify (fmt
, addr
);
1526 if (kind
== float_nan
)
1528 const char *sign
= floatformat_is_negative (fmt
, addr
)? "-" : "";
1529 const char *mantissa
= floatformat_mantissa (fmt
, addr
);
1530 return string_printf ("%snan(0x%s)", sign
, mantissa
);
1532 else if (kind
== float_infinite
)
1534 const char *sign
= floatformat_is_negative (fmt
, addr
)? "-" : "";
1535 return string_printf ("%sinf", sign
);
1539 /* Determine the format string to use on the host side. */
1540 std::string host_format
= floatformat_printf_format (fmt
, format
, 'R');
1542 gdb_mpfr
tmp (type
);
1543 from_target (type
, addr
, tmp
);
1545 int size
= mpfr_snprintf (NULL
, 0, host_format
.c_str (), tmp
.val
);
1546 std::string
str (size
, '\0');
1547 mpfr_sprintf (&str
[0], host_format
.c_str (), tmp
.val
);
1552 /* Parse string STRING into a target floating-number of type TYPE and
1553 store it as byte-stream ADDR. Return whether parsing succeeded. */
1555 mpfr_float_ops::from_string (gdb_byte
*addr
,
1556 const struct type
*type
,
1557 const std::string
&in
) const
1559 gdb_mpfr
tmp (type
);
1562 mpfr_strtofr (tmp
.val
, in
.c_str (), &endptr
, 0, MPFR_RNDN
);
1564 /* We only accept the whole string. */
1568 to_target (type
, tmp
, addr
);
1572 /* Convert the byte-stream ADDR, interpreted as floating-point type TYPE,
1573 to an integer value (rounding towards zero). */
1575 mpfr_float_ops::to_longest (const gdb_byte
*addr
,
1576 const struct type
*type
) const
1578 gdb_mpfr
tmp (type
);
1579 from_target (type
, addr
, tmp
);
1580 return mpfr_get_sj (tmp
.val
, MPFR_RNDZ
);
1583 /* Convert signed integer VAL to a target floating-number of type TYPE
1584 and store it as byte-stream ADDR. */
1586 mpfr_float_ops::from_longest (gdb_byte
*addr
,
1587 const struct type
*type
,
1590 gdb_mpfr
tmp (type
);
1591 mpfr_set_sj (tmp
.val
, val
, MPFR_RNDN
);
1592 to_target (type
, tmp
, addr
);
1595 /* Convert unsigned integer VAL to a target floating-number of type TYPE
1596 and store it as byte-stream ADDR. */
1598 mpfr_float_ops::from_ulongest (gdb_byte
*addr
,
1599 const struct type
*type
,
1602 gdb_mpfr
tmp (type
);
1603 mpfr_set_uj (tmp
.val
, val
, MPFR_RNDN
);
1604 to_target (type
, tmp
, addr
);
1607 /* Convert the byte-stream ADDR, interpreted as floating-point type TYPE,
1608 to a floating-point value in the host "double" format. */
1610 mpfr_float_ops::to_host_double (const gdb_byte
*addr
,
1611 const struct type
*type
) const
1613 gdb_mpfr
tmp (type
);
1614 from_target (type
, addr
, tmp
);
1615 return mpfr_get_d (tmp
.val
, MPFR_RNDN
);
1618 /* Convert floating-point value VAL in the host "double" format to a target
1619 floating-number of type TYPE and store it as byte-stream ADDR. */
1621 mpfr_float_ops::from_host_double (gdb_byte
*addr
,
1622 const struct type
*type
,
1625 gdb_mpfr
tmp (type
);
1626 mpfr_set_d (tmp
.val
, val
, MPFR_RNDN
);
1627 to_target (type
, tmp
, addr
);
1630 /* Convert a floating-point number of type FROM_TYPE from the target
1631 byte-stream FROM to a floating-point number of type TO_TYPE, and
1632 store it to the target byte-stream TO. */
1634 mpfr_float_ops::convert (const gdb_byte
*from
,
1635 const struct type
*from_type
,
1637 const struct type
*to_type
) const
1639 gdb_mpfr
from_tmp (from_type
), to_tmp (to_type
);
1640 from_target (from_type
, from
, from_tmp
);
1641 mpfr_set (to_tmp
.val
, from_tmp
.val
, MPFR_RNDN
);
1642 to_target (to_type
, to_tmp
, to
);
1645 /* Perform the binary operation indicated by OPCODE, using as operands the
1646 target byte streams X and Y, interpreted as floating-point numbers of
1647 types TYPE_X and TYPE_Y, respectively. Convert the result to type
1648 TYPE_RES and store it into the byte-stream RES. */
1650 mpfr_float_ops::binop (enum exp_opcode op
,
1651 const gdb_byte
*x
, const struct type
*type_x
,
1652 const gdb_byte
*y
, const struct type
*type_y
,
1653 gdb_byte
*res
, const struct type
*type_res
) const
1655 gdb_mpfr
x_tmp (type_x
), y_tmp (type_y
), tmp (type_res
);
1657 from_target (type_x
, x
, x_tmp
);
1658 from_target (type_y
, y
, y_tmp
);
1663 mpfr_add (tmp
.val
, x_tmp
.val
, y_tmp
.val
, MPFR_RNDN
);
1667 mpfr_sub (tmp
.val
, x_tmp
.val
, y_tmp
.val
, MPFR_RNDN
);
1671 mpfr_mul (tmp
.val
, x_tmp
.val
, y_tmp
.val
, MPFR_RNDN
);
1675 mpfr_div (tmp
.val
, x_tmp
.val
, y_tmp
.val
, MPFR_RNDN
);
1679 mpfr_pow (tmp
.val
, x_tmp
.val
, y_tmp
.val
, MPFR_RNDN
);
1683 mpfr_min (tmp
.val
, x_tmp
.val
, y_tmp
.val
, MPFR_RNDN
);
1687 mpfr_max (tmp
.val
, x_tmp
.val
, y_tmp
.val
, MPFR_RNDN
);
1691 error (_("Integer-only operation on floating point number."));
1695 to_target (type_res
, tmp
, res
);
1698 /* Compare the two target byte streams X and Y, interpreted as floating-point
1699 numbers of types TYPE_X and TYPE_Y, respectively. Return zero if X and Y
1700 are equal, -1 if X is less than Y, and 1 otherwise. */
1702 mpfr_float_ops::compare (const gdb_byte
*x
, const struct type
*type_x
,
1703 const gdb_byte
*y
, const struct type
*type_y
) const
1705 gdb_mpfr
x_tmp (type_x
), y_tmp (type_y
);
1707 from_target (type_x
, x
, x_tmp
);
1708 from_target (type_y
, y
, y_tmp
);
1710 if (mpfr_equal_p (x_tmp
.val
, y_tmp
.val
))
1712 else if (mpfr_less_p (x_tmp
.val
, y_tmp
.val
))
1721 /* Helper routines operating on decimal floating-point data. */
1723 /* Decimal floating point is one of the extension to IEEE 754, which is
1724 described in http://grouper.ieee.org/groups/754/revision.html and
1725 http://www2.hursley.ibm.com/decimal/. It completes binary floating
1726 point by representing floating point more exactly. */
1728 /* The order of the following headers is important for making sure
1729 decNumber structure is large enough to hold decimal128 digits. */
1731 #include "dpd/decimal128.h"
1732 #include "dpd/decimal64.h"
1733 #include "dpd/decimal32.h"
1735 /* When using decimal128, this is the maximum string length + 1
1736 (value comes from libdecnumber's DECIMAL128_String constant). */
1737 #define MAX_DECIMAL_STRING 43
1739 /* In GDB, we are using an array of gdb_byte to represent decimal values.
1740 They are stored in host byte order. This routine does the conversion if
1741 the target byte order is different. */
1743 match_endianness (const gdb_byte
*from
, const struct type
*type
, gdb_byte
*to
)
1745 gdb_assert (type
->code () == TYPE_CODE_DECFLOAT
);
1747 int len
= type
->length ();
1751 #define OPPOSITE_BYTE_ORDER BFD_ENDIAN_LITTLE
1753 #define OPPOSITE_BYTE_ORDER BFD_ENDIAN_BIG
1756 if (type_byte_order (type
) == OPPOSITE_BYTE_ORDER
)
1757 for (i
= 0; i
< len
; i
++)
1758 to
[i
] = from
[len
- i
- 1];
1760 for (i
= 0; i
< len
; i
++)
1766 /* Helper function to get the appropriate libdecnumber context for each size
1767 of decimal float. */
1769 set_decnumber_context (decContext
*ctx
, const struct type
*type
)
1771 gdb_assert (type
->code () == TYPE_CODE_DECFLOAT
);
1773 switch (type
->length ())
1776 decContextDefault (ctx
, DEC_INIT_DECIMAL32
);
1779 decContextDefault (ctx
, DEC_INIT_DECIMAL64
);
1782 decContextDefault (ctx
, DEC_INIT_DECIMAL128
);
1789 /* Check for errors signaled in the decimal context structure. */
1791 decimal_check_errors (decContext
*ctx
)
1793 /* An error here could be a division by zero, an overflow, an underflow or
1794 an invalid operation (from the DEC_Errors constant in decContext.h).
1795 Since GDB doesn't complain about division by zero, overflow or underflow
1796 errors for binary floating, we won't complain about them for decimal
1798 if (ctx
->status
& DEC_IEEE_854_Invalid_operation
)
1800 /* Leave only the error bits in the status flags. */
1801 ctx
->status
&= DEC_IEEE_854_Invalid_operation
;
1802 error (_("Cannot perform operation: %s"),
1803 decContextStatusToString (ctx
));
1807 /* Helper function to convert from libdecnumber's appropriate representation
1808 for computation to each size of decimal float. */
1810 decimal_from_number (const decNumber
*from
,
1811 gdb_byte
*to
, const struct type
*type
)
1817 set_decnumber_context (&set
, type
);
1819 switch (type
->length ())
1822 decimal32FromNumber ((decimal32
*) dec
, from
, &set
);
1825 decimal64FromNumber ((decimal64
*) dec
, from
, &set
);
1828 decimal128FromNumber ((decimal128
*) dec
, from
, &set
);
1831 error (_("Unknown decimal floating point type."));
1835 match_endianness (dec
, type
, to
);
1838 /* Helper function to convert each size of decimal float to libdecnumber's
1839 appropriate representation for computation. */
1841 decimal_to_number (const gdb_byte
*addr
, const struct type
*type
,
1845 match_endianness (addr
, type
, dec
);
1847 switch (type
->length ())
1850 decimal32ToNumber ((decimal32
*) dec
, to
);
1853 decimal64ToNumber ((decimal64
*) dec
, to
);
1856 decimal128ToNumber ((decimal128
*) dec
, to
);
1859 error (_("Unknown decimal floating point type."));
1864 /* Returns true if ADDR (which is of type TYPE) is the number zero. */
1866 decimal_is_zero (const gdb_byte
*addr
, const struct type
*type
)
1870 decimal_to_number (addr
, type
, &number
);
1872 return decNumberIsZero (&number
);
1876 /* Implementation of target_float_ops using the libdecnumber decNumber type
1877 as intermediate format. */
1879 class decimal_float_ops
: public target_float_ops
1882 std::string
to_string (const gdb_byte
*addr
, const struct type
*type
,
1883 const char *format
) const override
;
1884 bool from_string (gdb_byte
*addr
, const struct type
*type
,
1885 const std::string
&string
) const override
;
1887 LONGEST
to_longest (const gdb_byte
*addr
,
1888 const struct type
*type
) const override
;
1889 void from_longest (gdb_byte
*addr
, const struct type
*type
,
1890 LONGEST val
) const override
;
1891 void from_ulongest (gdb_byte
*addr
, const struct type
*type
,
1892 ULONGEST val
) const override
;
1893 double to_host_double (const gdb_byte
*addr
,
1894 const struct type
*type
) const override
1896 /* We don't support conversions between target decimal floating-point
1897 types and the host double type. */
1898 gdb_assert_not_reached ("invalid operation on decimal float");
1900 void from_host_double (gdb_byte
*addr
, const struct type
*type
,
1901 double val
) const override
1903 /* We don't support conversions between target decimal floating-point
1904 types and the host double type. */
1905 gdb_assert_not_reached ("invalid operation on decimal float");
1907 void convert (const gdb_byte
*from
, const struct type
*from_type
,
1908 gdb_byte
*to
, const struct type
*to_type
) const override
;
1910 void binop (enum exp_opcode opcode
,
1911 const gdb_byte
*x
, const struct type
*type_x
,
1912 const gdb_byte
*y
, const struct type
*type_y
,
1913 gdb_byte
*res
, const struct type
*type_res
) const override
;
1914 int compare (const gdb_byte
*x
, const struct type
*type_x
,
1915 const gdb_byte
*y
, const struct type
*type_y
) const override
;
1918 /* Convert decimal type to its string representation. LEN is the length
1919 of the decimal type, 4 bytes for decimal32, 8 bytes for decimal64 and
1920 16 bytes for decimal128. */
1922 decimal_float_ops::to_string (const gdb_byte
*addr
, const struct type
*type
,
1923 const char *format
= nullptr) const
1927 match_endianness (addr
, type
, dec
);
1929 if (format
!= nullptr)
1931 /* We don't handle format strings (yet). If the host printf supports
1932 decimal floating point types, just use this. Otherwise, fall back
1933 to printing the number while ignoring the format string. */
1934 #if defined (PRINTF_HAS_DECFLOAT)
1935 /* FIXME: This makes unwarranted assumptions about the host ABI! */
1936 return string_printf (format
, dec
);
1941 result
.resize (MAX_DECIMAL_STRING
);
1943 switch (type
->length ())
1946 decimal32ToString ((decimal32
*) dec
, &result
[0]);
1949 decimal64ToString ((decimal64
*) dec
, &result
[0]);
1952 decimal128ToString ((decimal128
*) dec
, &result
[0]);
1955 error (_("Unknown decimal floating point type."));
1962 /* Convert the string form of a decimal value to its decimal representation.
1963 LEN is the length of the decimal type, 4 bytes for decimal32, 8 bytes for
1964 decimal64 and 16 bytes for decimal128. */
1966 decimal_float_ops::from_string (gdb_byte
*addr
, const struct type
*type
,
1967 const std::string
&string
) const
1972 set_decnumber_context (&set
, type
);
1974 switch (type
->length ())
1977 decimal32FromString ((decimal32
*) dec
, string
.c_str (), &set
);
1980 decimal64FromString ((decimal64
*) dec
, string
.c_str (), &set
);
1983 decimal128FromString ((decimal128
*) dec
, string
.c_str (), &set
);
1986 error (_("Unknown decimal floating point type."));
1990 match_endianness (dec
, type
, addr
);
1992 /* Check for errors in the DFP operation. */
1993 decimal_check_errors (&set
);
1998 /* Converts a LONGEST to a decimal float of specified LEN bytes. */
2000 decimal_float_ops::from_longest (gdb_byte
*addr
, const struct type
*type
,
2005 if ((int32_t) from
!= from
)
2006 /* libdecnumber can convert only 32-bit integers. */
2007 error (_("Conversion of large integer to a "
2008 "decimal floating type is not supported."));
2010 decNumberFromInt32 (&number
, (int32_t) from
);
2012 decimal_from_number (&number
, addr
, type
);
2015 /* Converts a ULONGEST to a decimal float of specified LEN bytes. */
2017 decimal_float_ops::from_ulongest (gdb_byte
*addr
, const struct type
*type
,
2018 ULONGEST from
) const
2022 if ((uint32_t) from
!= from
)
2023 /* libdecnumber can convert only 32-bit integers. */
2024 error (_("Conversion of large integer to a "
2025 "decimal floating type is not supported."));
2027 decNumberFromUInt32 (&number
, (uint32_t) from
);
2029 decimal_from_number (&number
, addr
, type
);
2032 /* Converts a decimal float of LEN bytes to a LONGEST. */
2034 decimal_float_ops::to_longest (const gdb_byte
*addr
,
2035 const struct type
*type
) const
2037 /* libdecnumber has a function to convert from decimal to integer, but
2038 it doesn't work when the decimal number has a fractional part. */
2039 std::string str
= to_string (addr
, type
);
2040 return strtoll (str
.c_str (), NULL
, 10);
2043 /* Perform operation OP with operands X and Y with sizes LEN_X and LEN_Y
2044 and byte orders BYTE_ORDER_X and BYTE_ORDER_Y, and store value in
2045 RESULT with size LEN_RESULT and byte order BYTE_ORDER_RESULT. */
2047 decimal_float_ops::binop (enum exp_opcode op
,
2048 const gdb_byte
*x
, const struct type
*type_x
,
2049 const gdb_byte
*y
, const struct type
*type_y
,
2050 gdb_byte
*res
, const struct type
*type_res
) const
2053 decNumber number1
, number2
, number3
;
2055 decimal_to_number (x
, type_x
, &number1
);
2056 decimal_to_number (y
, type_y
, &number2
);
2058 set_decnumber_context (&set
, type_res
);
2063 decNumberAdd (&number3
, &number1
, &number2
, &set
);
2066 decNumberSubtract (&number3
, &number1
, &number2
, &set
);
2069 decNumberMultiply (&number3
, &number1
, &number2
, &set
);
2072 decNumberDivide (&number3
, &number1
, &number2
, &set
);
2075 decNumberPower (&number3
, &number1
, &number2
, &set
);
2078 error (_("Operation not valid for decimal floating point number."));
2082 /* Check for errors in the DFP operation. */
2083 decimal_check_errors (&set
);
2085 decimal_from_number (&number3
, res
, type_res
);
2088 /* Compares two numbers numerically. If X is less than Y then the return value
2089 will be -1. If they are equal, then the return value will be 0. If X is
2090 greater than the Y then the return value will be 1. */
2092 decimal_float_ops::compare (const gdb_byte
*x
, const struct type
*type_x
,
2093 const gdb_byte
*y
, const struct type
*type_y
) const
2095 decNumber number1
, number2
, result
;
2097 const struct type
*type_result
;
2099 decimal_to_number (x
, type_x
, &number1
);
2100 decimal_to_number (y
, type_y
, &number2
);
2102 /* Perform the comparison in the larger of the two sizes. */
2103 type_result
= type_x
->length () > type_y
->length () ? type_x
: type_y
;
2104 set_decnumber_context (&set
, type_result
);
2106 decNumberCompare (&result
, &number1
, &number2
, &set
);
2108 /* Check for errors in the DFP operation. */
2109 decimal_check_errors (&set
);
2111 if (decNumberIsNaN (&result
))
2112 error (_("Comparison with an invalid number (NaN)."));
2113 else if (decNumberIsZero (&result
))
2115 else if (decNumberIsNegative (&result
))
2121 /* Convert a decimal value from a decimal type with LEN_FROM bytes to a
2122 decimal type with LEN_TO bytes. */
2124 decimal_float_ops::convert (const gdb_byte
*from
, const struct type
*from_type
,
2125 gdb_byte
*to
, const struct type
*to_type
) const
2129 decimal_to_number (from
, from_type
, &number
);
2130 decimal_from_number (&number
, to
, to_type
);
2134 /* Typed floating-point routines. These routines operate on floating-point
2135 values in target format, represented by a byte buffer interpreted as a
2136 "struct type", which may be either a binary or decimal floating-point
2137 type (TYPE_CODE_FLT or TYPE_CODE_DECFLOAT). */
2139 /* Return whether TYPE1 and TYPE2 are of the same category (binary or
2140 decimal floating-point). */
2142 target_float_same_category_p (const struct type
*type1
,
2143 const struct type
*type2
)
2145 return type1
->code () == type2
->code ();
2148 /* Return whether TYPE1 and TYPE2 use the same floating-point format. */
2150 target_float_same_format_p (const struct type
*type1
,
2151 const struct type
*type2
)
2153 if (!target_float_same_category_p (type1
, type2
))
2156 switch (type1
->code ())
2159 return floatformat_from_type (type1
) == floatformat_from_type (type2
);
2161 case TYPE_CODE_DECFLOAT
:
2162 return (type1
->length () == type2
->length ()
2163 && (type_byte_order (type1
)
2164 == type_byte_order (type2
)));
2167 gdb_assert_not_reached ("unexpected type code");
2171 /* Return the size (without padding) of the target floating-point
2172 format used by TYPE. */
2174 target_float_format_length (const struct type
*type
)
2176 switch (type
->code ())
2179 return floatformat_totalsize_bytes (floatformat_from_type (type
));
2181 case TYPE_CODE_DECFLOAT
:
2182 return type
->length ();
2185 gdb_assert_not_reached ("unexpected type code");
2189 /* Identifiers of available host-side intermediate formats. These must
2190 be sorted so the that the more "general" kinds come later. */
2191 enum target_float_ops_kind
2193 /* Target binary floating-point formats that match a host format. */
2197 /* Any other target binary floating-point format. */
2199 /* Any target decimal floating-point format. */
2203 /* Given a target type TYPE, choose the best host-side intermediate format
2204 to perform operations on TYPE in. */
2205 static enum target_float_ops_kind
2206 get_target_float_ops_kind (const struct type
*type
)
2208 switch (type
->code ())
2212 const struct floatformat
*fmt
= floatformat_from_type (type
);
2214 /* Binary floating-point formats matching a host format. */
2215 if (fmt
== host_float_format
)
2216 return target_float_ops_kind::host_float
;
2217 if (fmt
== host_double_format
)
2218 return target_float_ops_kind::host_double
;
2219 if (fmt
== host_long_double_format
)
2220 return target_float_ops_kind::host_long_double
;
2222 /* Any other binary floating-point format. */
2223 return target_float_ops_kind::binary
;
2226 case TYPE_CODE_DECFLOAT
:
2228 /* Any decimal floating-point format. */
2229 return target_float_ops_kind::decimal
;
2233 gdb_assert_not_reached ("unexpected type code");
2237 /* Return target_float_ops to perform operations for KIND. */
2238 static const target_float_ops
*
2239 get_target_float_ops (enum target_float_ops_kind kind
)
2243 /* If the type format matches one of the host floating-point
2244 types, use that type as intermediate format. */
2245 case target_float_ops_kind::host_float
:
2247 static host_float_ops
<float> host_float_ops_float
;
2248 return &host_float_ops_float
;
2251 case target_float_ops_kind::host_double
:
2253 static host_float_ops
<double> host_float_ops_double
;
2254 return &host_float_ops_double
;
2257 case target_float_ops_kind::host_long_double
:
2259 static host_float_ops
<long double> host_float_ops_long_double
;
2260 return &host_float_ops_long_double
;
2263 /* For binary floating-point formats that do not match any host format,
2264 use mpfr_t as intermediate format to provide precise target-floating
2265 point emulation. However, if the MPFR library is not available,
2266 use the largest host floating-point type as intermediate format. */
2267 case target_float_ops_kind::binary
:
2270 static mpfr_float_ops binary_float_ops
;
2272 static host_float_ops
<long double> binary_float_ops
;
2274 return &binary_float_ops
;
2277 /* For decimal floating-point types, always use the libdecnumber
2278 decNumber type as intermediate format. */
2279 case target_float_ops_kind::decimal
:
2281 static decimal_float_ops decimal_float_ops
;
2282 return &decimal_float_ops
;
2286 gdb_assert_not_reached ("unexpected target_float_ops_kind");
2290 /* Given a target type TYPE, determine the best host-side intermediate format
2291 to perform operations on TYPE in. */
2292 static const target_float_ops
*
2293 get_target_float_ops (const struct type
*type
)
2295 enum target_float_ops_kind kind
= get_target_float_ops_kind (type
);
2296 return get_target_float_ops (kind
);
2299 /* The same for operations involving two target types TYPE1 and TYPE2. */
2300 static const target_float_ops
*
2301 get_target_float_ops (const struct type
*type1
, const struct type
*type2
)
2303 gdb_assert (type1
->code () == type2
->code ());
2305 enum target_float_ops_kind kind1
= get_target_float_ops_kind (type1
);
2306 enum target_float_ops_kind kind2
= get_target_float_ops_kind (type2
);
2308 /* Given the way the kinds are sorted, we simply choose the larger one;
2309 this will be able to hold values of either type. */
2310 return get_target_float_ops (std::max (kind1
, kind2
));
2313 /* Return whether the byte-stream ADDR holds a valid value of
2314 floating-point type TYPE. */
2316 target_float_is_valid (const gdb_byte
*addr
, const struct type
*type
)
2318 if (type
->code () == TYPE_CODE_FLT
)
2319 return floatformat_is_valid (floatformat_from_type (type
), addr
);
2321 if (type
->code () == TYPE_CODE_DECFLOAT
)
2324 gdb_assert_not_reached ("unexpected type code");
2327 /* Return whether the byte-stream ADDR, interpreted as floating-point
2328 type TYPE, is numerically equal to zero (of either sign). */
2330 target_float_is_zero (const gdb_byte
*addr
, const struct type
*type
)
2332 if (type
->code () == TYPE_CODE_FLT
)
2333 return (floatformat_classify (floatformat_from_type (type
), addr
)
2336 if (type
->code () == TYPE_CODE_DECFLOAT
)
2337 return decimal_is_zero (addr
, type
);
2339 gdb_assert_not_reached ("unexpected type code");
2342 /* Convert the byte-stream ADDR, interpreted as floating-point type TYPE,
2343 to a string, optionally using the print format FORMAT. */
2345 target_float_to_string (const gdb_byte
*addr
, const struct type
*type
,
2348 /* Unless we need to adhere to a specific format, provide special
2349 output for special cases of binary floating-point numbers. */
2350 if (format
== nullptr && type
->code () == TYPE_CODE_FLT
)
2352 const struct floatformat
*fmt
= floatformat_from_type (type
);
2354 /* Detect invalid representations. */
2355 if (!floatformat_is_valid (fmt
, addr
))
2356 return "<invalid float value>";
2358 /* Handle NaN and Inf. */
2359 enum float_kind kind
= floatformat_classify (fmt
, addr
);
2360 if (kind
== float_nan
)
2362 const char *sign
= floatformat_is_negative (fmt
, addr
)? "-" : "";
2363 const char *mantissa
= floatformat_mantissa (fmt
, addr
);
2364 return string_printf ("%snan(0x%s)", sign
, mantissa
);
2366 else if (kind
== float_infinite
)
2368 const char *sign
= floatformat_is_negative (fmt
, addr
)? "-" : "";
2369 return string_printf ("%sinf", sign
);
2373 const target_float_ops
*ops
= get_target_float_ops (type
);
2374 return ops
->to_string (addr
, type
, format
);
2377 /* Parse string STRING into a target floating-number of type TYPE and
2378 store it as byte-stream ADDR. Return whether parsing succeeded. */
2380 target_float_from_string (gdb_byte
*addr
, const struct type
*type
,
2381 const std::string
&string
)
2383 const target_float_ops
*ops
= get_target_float_ops (type
);
2384 return ops
->from_string (addr
, type
, string
);
2387 /* Convert the byte-stream ADDR, interpreted as floating-point type TYPE,
2388 to an integer value (rounding towards zero). */
2390 target_float_to_longest (const gdb_byte
*addr
, const struct type
*type
)
2392 const target_float_ops
*ops
= get_target_float_ops (type
);
2393 return ops
->to_longest (addr
, type
);
2396 /* Convert signed integer VAL to a target floating-number of type TYPE
2397 and store it as byte-stream ADDR. */
2399 target_float_from_longest (gdb_byte
*addr
, const struct type
*type
,
2402 const target_float_ops
*ops
= get_target_float_ops (type
);
2403 ops
->from_longest (addr
, type
, val
);
2406 /* Convert unsigned integer VAL to a target floating-number of type TYPE
2407 and store it as byte-stream ADDR. */
2409 target_float_from_ulongest (gdb_byte
*addr
, const struct type
*type
,
2412 const target_float_ops
*ops
= get_target_float_ops (type
);
2413 ops
->from_ulongest (addr
, type
, val
);
2416 /* Convert the byte-stream ADDR, interpreted as floating-point type TYPE,
2417 to a floating-point value in the host "double" format. */
2419 target_float_to_host_double (const gdb_byte
*addr
,
2420 const struct type
*type
)
2422 const target_float_ops
*ops
= get_target_float_ops (type
);
2423 return ops
->to_host_double (addr
, type
);
2426 /* Convert floating-point value VAL in the host "double" format to a target
2427 floating-number of type TYPE and store it as byte-stream ADDR. */
2429 target_float_from_host_double (gdb_byte
*addr
, const struct type
*type
,
2432 const target_float_ops
*ops
= get_target_float_ops (type
);
2433 ops
->from_host_double (addr
, type
, val
);
2436 /* Convert a floating-point number of type FROM_TYPE from the target
2437 byte-stream FROM to a floating-point number of type TO_TYPE, and
2438 store it to the target byte-stream TO. */
2440 target_float_convert (const gdb_byte
*from
, const struct type
*from_type
,
2441 gdb_byte
*to
, const struct type
*to_type
)
2443 /* We cannot directly convert between binary and decimal floating-point
2444 types, so go via an intermediary string. */
2445 if (!target_float_same_category_p (from_type
, to_type
))
2447 std::string str
= target_float_to_string (from
, from_type
);
2448 target_float_from_string (to
, to_type
, str
);
2452 /* Convert between two different formats in the same category. */
2453 if (!target_float_same_format_p (from_type
, to_type
))
2455 const target_float_ops
*ops
= get_target_float_ops (from_type
, to_type
);
2456 ops
->convert (from
, from_type
, to
, to_type
);
2460 /* The floating-point formats match, so we simply copy the data, ensuring
2461 possible padding bytes in the target buffer are zeroed out. */
2462 memset (to
, 0, to_type
->length ());
2463 memcpy (to
, from
, target_float_format_length (to_type
));
2466 /* Perform the binary operation indicated by OPCODE, using as operands the
2467 target byte streams X and Y, interpreted as floating-point numbers of
2468 types TYPE_X and TYPE_Y, respectively. Convert the result to type
2469 TYPE_RES and store it into the byte-stream RES.
2471 The three types must either be all binary floating-point types, or else
2472 all decimal floating-point types. Binary and decimal floating-point
2473 types cannot be mixed within a single operation. */
2475 target_float_binop (enum exp_opcode opcode
,
2476 const gdb_byte
*x
, const struct type
*type_x
,
2477 const gdb_byte
*y
, const struct type
*type_y
,
2478 gdb_byte
*res
, const struct type
*type_res
)
2480 gdb_assert (target_float_same_category_p (type_x
, type_res
));
2481 gdb_assert (target_float_same_category_p (type_y
, type_res
));
2483 const target_float_ops
*ops
= get_target_float_ops (type_x
, type_y
);
2484 ops
->binop (opcode
, x
, type_x
, y
, type_y
, res
, type_res
);
2487 /* Compare the two target byte streams X and Y, interpreted as floating-point
2488 numbers of types TYPE_X and TYPE_Y, respectively. Return zero if X and Y
2489 are equal, -1 if X is less than Y, and 1 otherwise.
2491 The two types must either both be binary floating-point types, or else
2492 both be decimal floating-point types. Binary and decimal floating-point
2493 types cannot compared directly against each other. */
2495 target_float_compare (const gdb_byte
*x
, const struct type
*type_x
,
2496 const gdb_byte
*y
, const struct type
*type_y
)
2498 gdb_assert (target_float_same_category_p (type_x
, type_y
));
2500 const target_float_ops
*ops
= get_target_float_ops (type_x
, type_y
);
2501 return ops
->compare (x
, type_x
, y
, type_y
);