binutils-gdb/gdb/gdbserver/i387-fp.c

291 lines
7.5 KiB
C

/* i387-specific utility functions, for the remote server for GDB.
Copyright 2000, 2001, 2002
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 "server.h"
#include "i387-fp.h"
int num_xmm_registers = 8;
/* Note: These functions preserve the reserved bits in control registers.
However, gdbserver promptly throws away that information. */
/* These structs should have the proper sizes and alignment on both
i386 and x86-64 machines. */
struct i387_fsave {
/* All these are only sixteen bits, plus padding, except for fop (which
is only eleven bits), and fooff / fioff (which are 32 bits each). */
unsigned int fctrl;
unsigned int fstat;
unsigned int ftag;
unsigned int fioff;
unsigned short fiseg;
unsigned short fop;
unsigned int fooff;
unsigned int foseg;
/* Space for eight 80-bit FP values. */
char st_space[80];
};
struct i387_fxsave {
/* All these are only sixteen bits, plus padding, except for fop (which
is only eleven bits), and fooff / fioff (which are 32 bits each). */
unsigned short fctrl;
unsigned short fstat;
unsigned short ftag;
unsigned short fop;
unsigned int fioff;
unsigned int fiseg;
unsigned int fooff;
unsigned int foseg;
unsigned int mxcsr;
unsigned int _pad1;
/* Space for eight 80-bit FP values in 128-bit spaces. */
char st_space[128];
/* Space for eight 128-bit XMM values, or 16 on x86-64. */
char xmm_space[256];
};
void
i387_cache_to_fsave (void *buf)
{
struct i387_fsave *fp = (struct i387_fsave *) buf;
int i;
int st0_regnum = find_regno ("st0");
unsigned long val, val2;
for (i = 0; i < 8; i++)
collect_register (i + st0_regnum, ((char *) &fp->st_space[0]) + i * 10);
collect_register_by_name ("fioff", &fp->fioff);
collect_register_by_name ("fooff", &fp->fooff);
/* This one's 11 bits... */
collect_register_by_name ("fop", &val2);
fp->fop = (val2 & 0x7FF) | (fp->fop & 0xF800);
/* Some registers are 16-bit. */
collect_register_by_name ("fctrl", &val);
*(unsigned short *) &fp->fctrl = val;
collect_register_by_name ("fstat", &val);
val &= 0xFFFF;
*(unsigned short *) &fp->fstat = val;
collect_register_by_name ("ftag", &val);
val &= 0xFFFF;
*(unsigned short *) &fp->ftag = val;
collect_register_by_name ("fiseg", &val);
val &= 0xFFFF;
*(unsigned short *) &fp->fiseg = val;
collect_register_by_name ("foseg", &val);
val &= 0xFFFF;
*(unsigned short *) &fp->foseg = val;
}
void
i387_fsave_to_cache (const void *buf)
{
struct i387_fsave *fp = (struct i387_fsave *) buf;
int i;
int st0_regnum = find_regno ("st0");
unsigned long val;
for (i = 0; i < 8; i++)
supply_register (i + st0_regnum, ((char *) &fp->st_space[0]) + i * 10);
supply_register_by_name ("fioff", &fp->fioff);
supply_register_by_name ("fooff", &fp->fooff);
/* Some registers are 16-bit. */
val = fp->fctrl & 0xFFFF;
supply_register_by_name ("fctrl", &val);
val = fp->fstat & 0xFFFF;
supply_register_by_name ("fstat", &val);
val = fp->ftag & 0xFFFF;
supply_register_by_name ("ftag", &val);
val = fp->fiseg & 0xFFFF;
supply_register_by_name ("fiseg", &val);
val = fp->foseg & 0xFFFF;
supply_register_by_name ("foseg", &val);
val = (fp->fop) & 0x7FF;
supply_register_by_name ("fop", &val);
}
void
i387_cache_to_fxsave (void *buf)
{
struct i387_fxsave *fp = (struct i387_fxsave *) buf;
int i;
int st0_regnum = find_regno ("st0");
int xmm0_regnum = find_regno ("xmm0");
unsigned long val, val2;
for (i = 0; i < 8; i++)
collect_register (i + st0_regnum, ((char *) &fp->st_space[0]) + i * 16);
for (i = 0; i < num_xmm_registers; i++)
collect_register (i + xmm0_regnum, ((char *) &fp->xmm_space[0]) + i * 16);
collect_register_by_name ("fioff", &fp->fioff);
collect_register_by_name ("fooff", &fp->fooff);
collect_register_by_name ("mxcsr", &fp->mxcsr);
/* This one's 11 bits... */
collect_register_by_name ("fop", &val2);
fp->fop = (val2 & 0x7FF) | (fp->fop & 0xF800);
/* Some registers are 16-bit. */
collect_register_by_name ("fctrl", &val);
*(unsigned short *) &fp->fctrl = val;
collect_register_by_name ("fstat", &val);
val &= 0xFFFF;
*(unsigned short *) &fp->fstat = val;
/* Convert to the simplifed tag form stored in fxsave data. */
collect_register_by_name ("ftag", &val);
val &= 0xFFFF;
for (i = 7; i >= 0; i--)
{
int tag = (val >> (i * 2)) & 3;
if (tag != 3)
val2 |= (1 << i);
}
*(unsigned short *) &fp->ftag = val2;
collect_register_by_name ("fiseg", &val);
val &= 0xFFFF;
*(unsigned short *) &fp->fiseg = val;
collect_register_by_name ("foseg", &val);
val &= 0xFFFF;
*(unsigned short *) &fp->foseg = val;
}
static int
i387_ftag (struct i387_fxsave *fp, int regno)
{
unsigned char *raw = &fp->st_space[regno * 16];
unsigned int exponent;
unsigned long fraction[2];
int integer;
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)
{
/* Special. */
return (2);
}
else if (exponent == 0x0000)
{
if (fraction[0] == 0x0000 && fraction[1] == 0x0000 && !integer)
{
/* Zero. */
return (1);
}
else
{
/* Special. */
return (2);
}
}
else
{
if (integer)
{
/* Valid. */
return (0);
}
else
{
/* Special. */
return (2);
}
}
}
void
i387_fxsave_to_cache (const void *buf)
{
struct i387_fxsave *fp = (struct i387_fxsave *) buf;
int i, top;
int st0_regnum = find_regno ("st0");
int xmm0_regnum = find_regno ("xmm0");
unsigned long val;
for (i = 0; i < 8; i++)
supply_register (i + st0_regnum, ((char *) &fp->st_space[0]) + i * 16);
for (i = 0; i < num_xmm_registers; i++)
supply_register (i + xmm0_regnum, ((char *) &fp->xmm_space[0]) + i * 16);
supply_register_by_name ("fioff", &fp->fioff);
supply_register_by_name ("fooff", &fp->fooff);
supply_register_by_name ("mxcsr", &fp->mxcsr);
/* Some registers are 16-bit. */
val = fp->fctrl & 0xFFFF;
supply_register_by_name ("fctrl", &val);
val = fp->fstat & 0xFFFF;
supply_register_by_name ("fstat", &val);
/* Generate the form of ftag data that GDB expects. */
top = (fp->fstat >> 11) & 0x7;
val = 0;
for (i = 7; i >= 0; i--)
{
int tag;
if (val & (1 << i))
tag = i387_ftag (fp, (i + 8 - top) % 8);
else
tag = 3;
val |= tag << (2 * i);
}
supply_register_by_name ("ftag", &val);
val = fp->fiseg & 0xFFFF;
supply_register_by_name ("fiseg", &val);
val = fp->foseg & 0xFFFF;
supply_register_by_name ("foseg", &val);
val = (fp->fop) & 0x7FF;
supply_register_by_name ("fop", &val);
}