404 lines
11 KiB
C
404 lines
11 KiB
C
/* Intel 387 floating point stuff.
|
||
Copyright (C) 1988, 89, 91, 98, 99, 2000 Free Software Foundation, Inc.
|
||
|
||
This file is part of GDB.
|
||
|
||
This program is free software; you can redistribute it and/or modify
|
||
it under the terms of the GNU General Public License as published by
|
||
the Free Software Foundation; either version 2 of the License, or
|
||
(at your option) any later version.
|
||
|
||
This program is distributed in the hope that it will be useful,
|
||
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||
GNU General Public License for more details.
|
||
|
||
You should have received a copy of the GNU General Public License
|
||
along with this program; if not, write to the Free Software
|
||
Foundation, Inc., 59 Temple Place - Suite 330,
|
||
Boston, MA 02111-1307, USA. */
|
||
|
||
#include "defs.h"
|
||
#include "frame.h"
|
||
#include "inferior.h"
|
||
#include "language.h"
|
||
#include "value.h"
|
||
#include "gdbcore.h"
|
||
#include "floatformat.h"
|
||
|
||
|
||
/* FIXME: Eliminate the next two functions when we have the time to
|
||
change all the callers. */
|
||
|
||
void i387_to_double PARAMS ((char *from, char *to));
|
||
void double_to_i387 PARAMS ((char *from, char *to));
|
||
|
||
void
|
||
i387_to_double (from, to)
|
||
char *from;
|
||
char *to;
|
||
{
|
||
floatformat_to_double (&floatformat_i387_ext, from, (double *) to);
|
||
}
|
||
|
||
void
|
||
double_to_i387 (from, to)
|
||
char *from;
|
||
char *to;
|
||
{
|
||
floatformat_from_double (&floatformat_i387_ext, (double *) from, to);
|
||
}
|
||
|
||
|
||
/* FIXME: The functions on this page are used by the old `info float'
|
||
implementations that a few of the i386 targets provide. These
|
||
functions should be removed if all of these have been converted to
|
||
use the generic implementation based on the new register file
|
||
layout. */
|
||
|
||
static void print_387_control_bits PARAMS ((unsigned int control));
|
||
static void print_387_status_bits PARAMS ((unsigned int status));
|
||
|
||
static void
|
||
print_387_control_bits (control)
|
||
unsigned int control;
|
||
{
|
||
switch ((control >> 8) & 3)
|
||
{
|
||
case 0:
|
||
puts_unfiltered (" 24 bit; ");
|
||
break;
|
||
case 1:
|
||
puts_unfiltered (" (bad); ");
|
||
break;
|
||
case 2:
|
||
puts_unfiltered (" 53 bit; ");
|
||
break;
|
||
case 3:
|
||
puts_unfiltered (" 64 bit; ");
|
||
break;
|
||
}
|
||
switch ((control >> 10) & 3)
|
||
{
|
||
case 0:
|
||
puts_unfiltered ("NEAR; ");
|
||
break;
|
||
case 1:
|
||
puts_unfiltered ("DOWN; ");
|
||
break;
|
||
case 2:
|
||
puts_unfiltered ("UP; ");
|
||
break;
|
||
case 3:
|
||
puts_unfiltered ("CHOP; ");
|
||
break;
|
||
}
|
||
if (control & 0x3f)
|
||
{
|
||
puts_unfiltered ("mask");
|
||
if (control & 0x0001)
|
||
puts_unfiltered (" INVAL");
|
||
if (control & 0x0002)
|
||
puts_unfiltered (" DENOR");
|
||
if (control & 0x0004)
|
||
puts_unfiltered (" DIVZ");
|
||
if (control & 0x0008)
|
||
puts_unfiltered (" OVERF");
|
||
if (control & 0x0010)
|
||
puts_unfiltered (" UNDER");
|
||
if (control & 0x0020)
|
||
puts_unfiltered (" LOS");
|
||
puts_unfiltered (";");
|
||
}
|
||
|
||
if (control & 0xe080)
|
||
warning ("\nreserved bits on: %s",
|
||
local_hex_string (control & 0xe080));
|
||
}
|
||
|
||
void
|
||
print_387_control_word (control)
|
||
unsigned int control;
|
||
{
|
||
printf_filtered ("control %s:", local_hex_string(control & 0xffff));
|
||
print_387_control_bits (control);
|
||
puts_unfiltered ("\n");
|
||
}
|
||
|
||
static void
|
||
print_387_status_bits (status)
|
||
unsigned int status;
|
||
{
|
||
printf_unfiltered (" flags %d%d%d%d; ",
|
||
(status & 0x4000) != 0,
|
||
(status & 0x0400) != 0,
|
||
(status & 0x0200) != 0,
|
||
(status & 0x0100) != 0);
|
||
printf_unfiltered ("top %d; ", (status >> 11) & 7);
|
||
if (status & 0xff)
|
||
{
|
||
puts_unfiltered ("excep");
|
||
if (status & 0x0001) puts_unfiltered (" INVAL");
|
||
if (status & 0x0002) puts_unfiltered (" DENOR");
|
||
if (status & 0x0004) puts_unfiltered (" DIVZ");
|
||
if (status & 0x0008) puts_unfiltered (" OVERF");
|
||
if (status & 0x0010) puts_unfiltered (" UNDER");
|
||
if (status & 0x0020) puts_unfiltered (" LOS");
|
||
if (status & 0x0040) puts_unfiltered (" STACK");
|
||
}
|
||
}
|
||
|
||
void
|
||
print_387_status_word (status)
|
||
unsigned int status;
|
||
{
|
||
printf_filtered ("status %s:", local_hex_string (status & 0xffff));
|
||
print_387_status_bits (status);
|
||
puts_unfiltered ("\n");
|
||
}
|
||
|
||
|
||
/* Implement the `info float' layout based on the register definitions
|
||
in `tm-i386.h'. */
|
||
|
||
/* Print the floating point number specified by RAW. */
|
||
static void
|
||
print_i387_value (char *raw)
|
||
{
|
||
DOUBLEST value;
|
||
|
||
/* Avoid call to floatformat_to_doublest if possible to preserve as
|
||
much information as possible. */
|
||
|
||
#ifdef HAVE_LONG_DOUBLE
|
||
if (sizeof (value) == sizeof (long double)
|
||
&& HOST_LONG_DOUBLE_FORMAT == &floatformat_i387_ext)
|
||
{
|
||
/* Copy straight over, but take care of the padding. */
|
||
memcpy (&value, raw, FPU_REG_RAW_SIZE);
|
||
memset ((char *) &value + FPU_REG_RAW_SIZE, 0,
|
||
sizeof (value) - FPU_REG_RAW_SIZE);
|
||
}
|
||
else
|
||
#endif
|
||
floatformat_to_doublest (&floatformat_i387_ext, raw, &value);
|
||
|
||
/* We try to print 19 digits. The last digit may or may not contain
|
||
garbage, but we'd better print one too many. We need enough room
|
||
to print the value, 1 position for the sign, 1 for the decimal
|
||
point, 19 for the digits and 6 for the exponent adds up to 27. */
|
||
#ifdef PRINTF_HAS_LONG_DOUBLE
|
||
printf_filtered (" %-+27.19Lg", (long double) value);
|
||
#else
|
||
printf_filtered (" %-+27.19g", (double) value);
|
||
#endif
|
||
}
|
||
|
||
/* Print the classification for the register contents RAW. */
|
||
static void
|
||
print_i387_ext (unsigned char *raw)
|
||
{
|
||
int sign;
|
||
int integer;
|
||
unsigned int exponent;
|
||
unsigned long fraction[2];
|
||
|
||
sign = raw[9] & 0x80;
|
||
integer = raw[7] & 0x80;
|
||
exponent = (((raw[9] & 0x7f) << 8) | raw[8]);
|
||
fraction[0] = ((raw[3] << 24) | (raw[2] << 16) | (raw[1] << 8) | raw[0]);
|
||
fraction[1] = (((raw[7] & 0x7f) << 24) | (raw[6] << 16)
|
||
| (raw[5] << 8) | raw[4]);
|
||
|
||
if (exponent == 0x7fff && integer)
|
||
{
|
||
if (fraction[0] == 0x00000000 && fraction[1] == 0x00000000)
|
||
/* Infinity. */
|
||
printf_filtered (" %cInf", (sign ? '-' : '+'));
|
||
else if (sign && fraction[0] == 0x00000000 && fraction[1] == 0x40000000)
|
||
/* Real Indefinite (QNaN). */
|
||
puts_unfiltered (" Real Indefinite (QNaN)");
|
||
else if (fraction[1] & 0x40000000)
|
||
/* QNaN. */
|
||
puts_filtered (" QNaN");
|
||
else
|
||
/* SNaN. */
|
||
puts_filtered (" SNaN");
|
||
}
|
||
else if (exponent < 0x7fff && exponent > 0x0000 && integer)
|
||
/* Normal. */
|
||
print_i387_value (raw);
|
||
else if (exponent == 0x0000)
|
||
{
|
||
/* Denormal or zero. */
|
||
print_i387_value (raw);
|
||
|
||
if (integer)
|
||
/* Pseudo-denormal. */
|
||
puts_filtered (" Pseudo-denormal");
|
||
else if (fraction[0] || fraction[1])
|
||
/* Denormal. */
|
||
puts_filtered (" Denormal");
|
||
}
|
||
else
|
||
/* Unsupported. */
|
||
puts_filtered (" Unsupported");
|
||
}
|
||
|
||
/* Print the status word STATUS. */
|
||
static void
|
||
print_i387_status_word (unsigned int status)
|
||
{
|
||
printf_filtered ("Status Word: %s",
|
||
local_hex_string_custom (status, "04"));
|
||
puts_filtered (" ");
|
||
printf_filtered (" %s", (status & 0x0001) ? "IE" : " ");
|
||
printf_filtered (" %s", (status & 0x0002) ? "DE" : " ");
|
||
printf_filtered (" %s", (status & 0x0004) ? "ZE" : " ");
|
||
printf_filtered (" %s", (status & 0x0008) ? "OE" : " ");
|
||
printf_filtered (" %s", (status & 0x0010) ? "UE" : " ");
|
||
printf_filtered (" %s", (status & 0x0020) ? "PE" : " ");
|
||
puts_filtered (" ");
|
||
printf_filtered (" %s", (status & 0x0080) ? "ES" : " ");
|
||
puts_filtered (" ");
|
||
printf_filtered (" %s", (status & 0x0080) ? "SF" : " ");
|
||
puts_filtered (" ");
|
||
printf_filtered (" %s", (status & 0x0100) ? "C0" : " ");
|
||
printf_filtered (" %s", (status & 0x0200) ? "C1" : " ");
|
||
printf_filtered (" %s", (status & 0x0400) ? "C2" : " ");
|
||
printf_filtered (" %s", (status & 0x4000) ? "C3" : " ");
|
||
|
||
puts_filtered ("\n");
|
||
|
||
printf_filtered (" TOP: %d\n", ((status >> 11) & 7));
|
||
}
|
||
|
||
/* Print the control word CONTROL. */
|
||
static void
|
||
print_i387_control_word (unsigned int control)
|
||
{
|
||
printf_filtered ("Control Word: %s",
|
||
local_hex_string_custom (control, "04"));
|
||
puts_filtered (" ");
|
||
printf_filtered (" %s", (control & 0x0001) ? "IM" : " ");
|
||
printf_filtered (" %s", (control & 0x0002) ? "DM" : " ");
|
||
printf_filtered (" %s", (control & 0x0004) ? "ZM" : " ");
|
||
printf_filtered (" %s", (control & 0x0008) ? "OM" : " ");
|
||
printf_filtered (" %s", (control & 0x0010) ? "UM" : " ");
|
||
printf_filtered (" %s", (control & 0x0020) ? "PM" : " ");
|
||
|
||
puts_filtered ("\n");
|
||
|
||
puts_filtered (" PC: ");
|
||
switch ((control >> 8) & 3)
|
||
{
|
||
case 0:
|
||
puts_filtered ("Single Precision (24-bits)\n");
|
||
break;
|
||
case 1:
|
||
puts_filtered ("Reserved\n");
|
||
break;
|
||
case 2:
|
||
puts_filtered ("Double Precision (53-bits)\n");
|
||
break;
|
||
case 3:
|
||
puts_filtered ("Extended Precision (64-bits)\n");
|
||
break;
|
||
}
|
||
|
||
puts_filtered (" RC: ");
|
||
switch ((control >> 10) & 3)
|
||
{
|
||
case 0:
|
||
puts_filtered ("Round to nearest\n");
|
||
break;
|
||
case 1:
|
||
puts_filtered ("Round down\n");
|
||
break;
|
||
case 2:
|
||
puts_filtered ("Round up\n");
|
||
break;
|
||
case 3:
|
||
puts_filtered ("Round toward zero\n");
|
||
break;
|
||
}
|
||
}
|
||
|
||
/* Print out the i387 floating poin state. */
|
||
void
|
||
i387_float_info (void)
|
||
{
|
||
unsigned int fctrl;
|
||
unsigned int fstat;
|
||
unsigned int ftag;
|
||
unsigned int fiseg;
|
||
unsigned int fioff;
|
||
unsigned int foseg;
|
||
unsigned int fooff;
|
||
unsigned int fop;
|
||
int fpreg;
|
||
int top;
|
||
|
||
fctrl = read_register (FCTRL_REGNUM);
|
||
fstat = read_register (FSTAT_REGNUM);
|
||
ftag = read_register (FTAG_REGNUM);
|
||
fiseg = read_register (FCS_REGNUM);
|
||
fioff = read_register (FCOFF_REGNUM);
|
||
foseg = read_register (FDS_REGNUM);
|
||
fooff = read_register (FDOFF_REGNUM);
|
||
fop = read_register (FOP_REGNUM);
|
||
|
||
top = ((fstat >> 11) & 7);
|
||
|
||
for (fpreg = 7; fpreg >= 0; fpreg--)
|
||
{
|
||
unsigned char raw[FPU_REG_RAW_SIZE];
|
||
int tag = (ftag >> (fpreg * 2)) & 3;
|
||
int i;
|
||
|
||
printf_filtered ("%sR%d: ", fpreg == top ? "=>" : " ", fpreg);
|
||
|
||
switch (tag)
|
||
{
|
||
case 0:
|
||
puts_filtered ("Valid ");
|
||
break;
|
||
case 1:
|
||
puts_filtered ("Zero ");
|
||
break;
|
||
case 2:
|
||
puts_filtered ("Special ");
|
||
break;
|
||
case 3:
|
||
puts_filtered ("Empty ");
|
||
break;
|
||
}
|
||
|
||
read_register_gen ((fpreg + 8 - top) % 8 + FP0_REGNUM, raw);
|
||
|
||
puts_filtered ("0x");
|
||
for (i = 9; i >= 0; i--)
|
||
printf_filtered ("%02x", raw[i]);
|
||
|
||
if (tag != 3)
|
||
print_i387_ext (raw);
|
||
|
||
puts_filtered ("\n");
|
||
}
|
||
|
||
puts_filtered ("\n");
|
||
|
||
print_i387_status_word (fstat);
|
||
print_i387_control_word (fctrl);
|
||
printf_filtered ("Tag Word: %s\n",
|
||
local_hex_string_custom (ftag, "04"));
|
||
printf_filtered ("Instruction Pointer: %s:",
|
||
local_hex_string_custom (fiseg, "02"));
|
||
printf_filtered ("%s\n", local_hex_string_custom (fioff, "08"));
|
||
printf_filtered ("Operand Pointer: %s:",
|
||
local_hex_string_custom (foseg, "02"));
|
||
printf_filtered ("%s\n", local_hex_string_custom (fooff, "08"));
|
||
printf_filtered ("Opcode: %s\n",
|
||
local_hex_string_custom (fop ? (fop | 0xd800) : 0, "04"));
|
||
}
|