613 lines
15 KiB
C
613 lines
15 KiB
C
/*
|
|
* errors.c
|
|
*
|
|
* The error handling functions for wm-FPU-emu
|
|
*
|
|
*
|
|
* Copyright (C) 1992,1993,1994
|
|
* W. Metzenthen, 22 Parker St, Ormond, Vic 3163,
|
|
* Australia. E-mail billm@vaxc.cc.monash.edu.au
|
|
* All rights reserved.
|
|
*
|
|
* This copyright notice covers the redistribution and use of the
|
|
* FPU emulator developed by W. Metzenthen. It covers only its use
|
|
* in the 386BSD, FreeBSD and NetBSD operating systems. Any other
|
|
* use is not permitted under this copyright.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. Redistributions in binary form must include information specifying
|
|
* that source code for the emulator is freely available and include
|
|
* either:
|
|
* a) an offer to provide the source code for a nominal distribution
|
|
* fee, or
|
|
* b) list at least two alternative methods whereby the source
|
|
* can be obtained, e.g. a publically accessible bulletin board
|
|
* and an anonymous ftp site from which the software can be
|
|
* downloaded.
|
|
* 3. All advertising materials specifically mentioning features or use of
|
|
* this emulator must acknowledge that it was developed by W. Metzenthen.
|
|
* 4. The name of W. Metzenthen may not be used to endorse or promote
|
|
* products derived from this software without specific prior written
|
|
* permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
|
|
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
|
|
* AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
|
|
* W. METZENTHEN BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
|
|
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
|
|
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
|
|
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
|
|
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
|
|
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
|
|
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
|
*
|
|
*
|
|
* The purpose of this copyright, based upon the Berkeley copyright, is to
|
|
* ensure that the covered software remains freely available to everyone.
|
|
*
|
|
* The software (with necessary differences) is also available, but under
|
|
* the terms of the GNU copyleft, for the Linux operating system and for
|
|
* the djgpp ms-dos extender.
|
|
*
|
|
* W. Metzenthen June 1994.
|
|
*
|
|
*
|
|
* $Id: errors.c,v 1.7 1997/02/22 09:29:01 peter Exp $
|
|
*
|
|
*/
|
|
|
|
/*---------------------------------------------------------------------------+
|
|
| Note: |
|
|
| The file contains code which accesses user memory. |
|
|
| Emulator static data may change when user memory is accessed, due to |
|
|
| other processes using the emulator while swapping is in progress. |
|
|
+---------------------------------------------------------------------------*/
|
|
|
|
|
|
|
|
|
|
|
|
#include <sys/param.h>
|
|
#include <sys/systm.h>
|
|
#include <sys/proc.h>
|
|
#include <machine/pcb.h>
|
|
|
|
#include <gnu/i386/fpemul/fpu_emu.h>
|
|
#include <gnu/i386/fpemul/fpu_system.h>
|
|
#include <gnu/i386/fpemul/exception.h>
|
|
#include <gnu/i386/fpemul/status_w.h>
|
|
#include <gnu/i386/fpemul/control_w.h>
|
|
#include <gnu/i386/fpemul/reg_constant.h>
|
|
#include <gnu/i386/fpemul/version.h>
|
|
|
|
/* */
|
|
#undef PRINT_MESSAGES
|
|
/* */
|
|
|
|
|
|
void
|
|
Un_impl(void)
|
|
{
|
|
unsigned char byte1, FPU_modrm;
|
|
|
|
REENTRANT_CHECK(OFF);
|
|
byte1 = fubyte((unsigned char *) FPU_ORIG_EIP);
|
|
FPU_modrm = fubyte(1 + (unsigned char *) FPU_ORIG_EIP);
|
|
|
|
printf("Unimplemented FPU Opcode at eip=%p : %02x ",
|
|
FPU_ORIG_EIP, byte1);
|
|
|
|
if (FPU_modrm >= 0300)
|
|
printf("%02x (%02x+%d)\n", FPU_modrm, FPU_modrm & 0xf8, FPU_modrm & 7);
|
|
else
|
|
printf("/%d\n", (FPU_modrm >> 3) & 7);
|
|
REENTRANT_CHECK(ON);
|
|
|
|
EXCEPTION(EX_Invalid);
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
void
|
|
emu_printall()
|
|
{
|
|
int i;
|
|
static char *tag_desc[] = {"Valid", "Zero", "ERROR", "ERROR",
|
|
"DeNorm", "Inf", "NaN", "Empty"};
|
|
unsigned char byte1, FPU_modrm;
|
|
|
|
REENTRANT_CHECK(OFF);
|
|
byte1 = fubyte((unsigned char *) FPU_ORIG_EIP);
|
|
FPU_modrm = fubyte(1 + (unsigned char *) FPU_ORIG_EIP);
|
|
|
|
#ifdef DEBUGGING
|
|
if (status_word & SW_Backward)
|
|
printf("SW: backward compatibility\n");
|
|
if (status_word & SW_C3)
|
|
printf("SW: condition bit 3\n");
|
|
if (status_word & SW_C2)
|
|
printf("SW: condition bit 2\n");
|
|
if (status_word & SW_C1)
|
|
printf("SW: condition bit 1\n");
|
|
if (status_word & SW_C0)
|
|
printf("SW: condition bit 0\n");
|
|
if (status_word & SW_Summary)
|
|
printf("SW: exception summary\n");
|
|
if (status_word & SW_Stack_Fault)
|
|
printf("SW: stack fault\n");
|
|
if (status_word & SW_Precision)
|
|
printf("SW: loss of precision\n");
|
|
if (status_word & SW_Underflow)
|
|
printf("SW: underflow\n");
|
|
if (status_word & SW_Overflow)
|
|
printf("SW: overflow\n");
|
|
if (status_word & SW_Zero_Div)
|
|
printf("SW: divide by zero\n");
|
|
if (status_word & SW_Denorm_Op)
|
|
printf("SW: denormalized operand\n");
|
|
if (status_word & SW_Invalid)
|
|
printf("SW: invalid operation\n");
|
|
#endif /* DEBUGGING */
|
|
|
|
status_word = status_word & ~SW_Top;
|
|
status_word |= (top & 7) << SW_Top_Shift;
|
|
|
|
printf("At %p: %02x ", FPU_ORIG_EIP, byte1);
|
|
if (FPU_modrm >= 0300)
|
|
printf("%02x (%02x+%d)\n", FPU_modrm, FPU_modrm & 0xf8, FPU_modrm & 7);
|
|
else
|
|
printf("/%d, mod=%d rm=%d\n",
|
|
(FPU_modrm >> 3) & 7, (FPU_modrm >> 6) & 3, FPU_modrm & 7);
|
|
|
|
printf(" SW: b=%d st=%d es=%d sf=%d cc=%d%d%d%d ef=%d%d%d%d%d%d\n",
|
|
status_word & 0x8000 ? 1 : 0, /* busy */
|
|
(status_word & 0x3800) >> 11, /* stack top pointer */
|
|
status_word & 0x80 ? 1 : 0, /* Error summary status */
|
|
status_word & 0x40 ? 1 : 0, /* Stack flag */
|
|
status_word & SW_C3 ? 1 : 0, status_word & SW_C2 ? 1 : 0, /* cc */
|
|
status_word & SW_C1 ? 1 : 0, status_word & SW_C0 ? 1 : 0, /* cc */
|
|
status_word & SW_Precision ? 1 : 0, status_word & SW_Underflow ? 1 : 0,
|
|
status_word & SW_Overflow ? 1 : 0, status_word & SW_Zero_Div ? 1 : 0,
|
|
status_word & SW_Denorm_Op ? 1 : 0, status_word & SW_Invalid ? 1 : 0);
|
|
|
|
printf(" CW: ic=%d rc=%d%d pc=%d%d iem=%d ef=%d%d%d%d%d%d\n",
|
|
control_word & 0x1000 ? 1 : 0,
|
|
(control_word & 0x800) >> 11, (control_word & 0x400) >> 10,
|
|
(control_word & 0x200) >> 9, (control_word & 0x100) >> 8,
|
|
control_word & 0x80 ? 1 : 0,
|
|
control_word & SW_Precision ? 1 : 0, control_word & SW_Underflow ? 1 : 0,
|
|
control_word & SW_Overflow ? 1 : 0, control_word & SW_Zero_Div ? 1 : 0,
|
|
control_word & SW_Denorm_Op ? 1 : 0, control_word & SW_Invalid ? 1 : 0);
|
|
|
|
for (i = 0; i < 8; i++) {
|
|
FPU_REG *r = &st(i);
|
|
switch (r->tag) {
|
|
case TW_Empty:
|
|
continue;
|
|
break;
|
|
case TW_Zero:
|
|
printf("st(%d) %c .0000 0000 0000 0000 ",
|
|
i, r->sign ? '-' : '+');
|
|
break;
|
|
case TW_Valid:
|
|
case TW_NaN:
|
|
case TW_Denormal:
|
|
case TW_Infinity:
|
|
printf("st(%d) %c .%04x %04x %04x %04x e%+-6d ", i,
|
|
r->sign ? '-' : '+',
|
|
(long) (r->sigh >> 16),
|
|
(long) (r->sigh & 0xFFFF),
|
|
(long) (r->sigl >> 16),
|
|
(long) (r->sigl & 0xFFFF),
|
|
r->exp - EXP_BIAS + 1);
|
|
break;
|
|
default:
|
|
printf("Whoops! Error in errors.c ");
|
|
break;
|
|
}
|
|
printf("%s\n", tag_desc[(int) (unsigned) r->tag]);
|
|
}
|
|
|
|
printf("[data] %c .%04x %04x %04x %04x e%+-6d ",
|
|
FPU_loaded_data.sign ? '-' : '+',
|
|
(long) (FPU_loaded_data.sigh >> 16),
|
|
(long) (FPU_loaded_data.sigh & 0xFFFF),
|
|
(long) (FPU_loaded_data.sigl >> 16),
|
|
(long) (FPU_loaded_data.sigl & 0xFFFF),
|
|
FPU_loaded_data.exp - EXP_BIAS + 1);
|
|
printf("%s\n", tag_desc[(int) (unsigned) FPU_loaded_data.tag]);
|
|
REENTRANT_CHECK(ON);
|
|
|
|
}
|
|
|
|
static struct {
|
|
int type;
|
|
char *name;
|
|
} exception_names[] = {
|
|
{
|
|
EX_StackOver, "stack overflow"
|
|
},
|
|
{
|
|
EX_StackUnder, "stack underflow"
|
|
},
|
|
{
|
|
EX_Precision, "loss of precision"
|
|
},
|
|
{
|
|
EX_Underflow, "underflow"
|
|
},
|
|
{
|
|
EX_Overflow, "overflow"
|
|
},
|
|
{
|
|
EX_ZeroDiv, "divide by zero"
|
|
},
|
|
{
|
|
EX_Denormal, "denormalized operand"
|
|
},
|
|
{
|
|
EX_Invalid, "invalid operation"
|
|
},
|
|
{
|
|
EX_INTERNAL, "INTERNAL BUG in " FPU_VERSION
|
|
},
|
|
{
|
|
0, NULL
|
|
}
|
|
};
|
|
/*
|
|
EX_INTERNAL is always given with a code which indicates where the
|
|
error was detected.
|
|
|
|
Internal error types:
|
|
0x14 in e14.c
|
|
0x1nn in a *.c file:
|
|
0x101 in reg_add_sub.c
|
|
0x102 in reg_mul.c
|
|
0x103 in poly_sin.c
|
|
0x104 in poly_tan.c
|
|
0x105 in reg_mul.c
|
|
0x106 in reg_mov.c
|
|
0x107 in fpu_trig.c
|
|
0x108 in reg_compare.c
|
|
0x109 in reg_compare.c
|
|
0x110 in reg_add_sub.c
|
|
0x111 in interface.c
|
|
0x112 in fpu_trig.c
|
|
0x113 in reg_add_sub.c
|
|
0x114 in reg_ld_str.c
|
|
0x115 in fpu_trig.c
|
|
0x116 in fpu_trig.c
|
|
0x117 in fpu_trig.c
|
|
0x118 in fpu_trig.c
|
|
0x119 in fpu_trig.c
|
|
0x120 in poly_atan.c
|
|
0x121 in reg_compare.c
|
|
0x122 in reg_compare.c
|
|
0x123 in reg_compare.c
|
|
0x2nn in an *.s file:
|
|
0x201 in reg_u_add.S
|
|
0x202 in reg_u_div.S
|
|
0x203 in reg_u_div.S
|
|
0x204 in reg_u_div.S
|
|
0x205 in reg_u_mul.S
|
|
0x206 in reg_u_sub.S
|
|
0x207 in wm_sqrt.S
|
|
0x208 in reg_div.S
|
|
0x209 in reg_u_sub.S
|
|
0x210 in reg_u_sub.S
|
|
0x211 in reg_u_sub.S
|
|
0x212 in reg_u_sub.S
|
|
0x213 in wm_sqrt.S
|
|
0x214 in wm_sqrt.S
|
|
0x215 in wm_sqrt.S
|
|
0x216 in reg_round.S
|
|
0x217 in reg_round.S
|
|
0x218 in reg_round.S
|
|
*/
|
|
|
|
void
|
|
exception(int n)
|
|
{
|
|
int i, int_type;
|
|
|
|
int_type = 0; /* Needed only to stop compiler warnings */
|
|
if (n & EX_INTERNAL) {
|
|
int_type = n - EX_INTERNAL;
|
|
n = EX_INTERNAL;
|
|
/* Set lots of exception bits! */
|
|
status_word |= (SW_Exc_Mask | SW_Summary | FPU_BUSY);
|
|
} else {
|
|
/* Extract only the bits which we use to set the status word */
|
|
n &= (SW_Exc_Mask);
|
|
/* Set the corresponding exception bit */
|
|
status_word |= n;
|
|
if (status_word & ~control_word & CW_Exceptions)
|
|
status_word |= SW_Summary;
|
|
if (n & (SW_Stack_Fault | EX_Precision)) {
|
|
if (!(n & SW_C1))
|
|
/* This bit distinguishes over- from underflow
|
|
* for a stack fault, and roundup from
|
|
* round-down for precision loss. */
|
|
status_word &= ~SW_C1;
|
|
}
|
|
}
|
|
|
|
REENTRANT_CHECK(OFF);
|
|
if ((~control_word & n & CW_Exceptions) || (n == EX_INTERNAL)) {
|
|
#ifdef PRINT_MESSAGES
|
|
/* My message from the sponsor */
|
|
printf(FPU_VERSION " " __DATE__ " (C) W. Metzenthen.\n");
|
|
#endif /* PRINT_MESSAGES */
|
|
|
|
/* Get a name string for error reporting */
|
|
for (i = 0; exception_names[i].type; i++)
|
|
if ((exception_names[i].type & n) == exception_names[i].type)
|
|
break;
|
|
|
|
if (exception_names[i].type) {
|
|
#ifdef PRINT_MESSAGES
|
|
printf("FP Exception: %s!\n", exception_names[i].name);
|
|
#endif /* PRINT_MESSAGES */
|
|
} else
|
|
printf("FP emulator: Unknown Exception: 0x%04x!\n", n);
|
|
|
|
if (n == EX_INTERNAL) {
|
|
printf("FP emulator: Internal error type 0x%04x\n", int_type);
|
|
emu_printall();
|
|
}
|
|
#ifdef PRINT_MESSAGES
|
|
else
|
|
emu_printall();
|
|
#endif /* PRINT_MESSAGES */
|
|
|
|
/* The 80486 generates an interrupt on the next non-control
|
|
* FPU instruction. So we need some means of flagging it. We
|
|
* use the ES (Error Summary) bit for this, assuming that this
|
|
* is the way a real FPU does it (until I can check it out),
|
|
* if not, then some method such as the following kludge might
|
|
* be needed. */
|
|
/* regs[0].tag |= TW_FPU_Interrupt; */
|
|
}
|
|
REENTRANT_CHECK(ON);
|
|
|
|
#ifdef __DEBUG__
|
|
math_abort(SIGFPE);
|
|
#endif /* __DEBUG__ */
|
|
|
|
}
|
|
|
|
|
|
/* Real operation attempted on two operands, one a NaN */
|
|
void
|
|
real_2op_NaN(FPU_REG * a, FPU_REG * b, FPU_REG * dest)
|
|
{
|
|
FPU_REG *x;
|
|
int signalling;
|
|
|
|
x = a;
|
|
if (a->tag == TW_NaN) {
|
|
if (b->tag == TW_NaN) {
|
|
signalling = !(a->sigh & b->sigh & 0x40000000);
|
|
/* find the "larger" */
|
|
if (*(long long *) &(a->sigl) < *(long long *) &(b->sigl))
|
|
x = b;
|
|
} else {
|
|
/* return the quiet version of the NaN in a */
|
|
signalling = !(a->sigh & 0x40000000);
|
|
}
|
|
} else
|
|
#ifdef PARANOID
|
|
if (b->tag == TW_NaN)
|
|
#endif /* PARANOID */
|
|
{
|
|
signalling = !(b->sigh & 0x40000000);
|
|
x = b;
|
|
}
|
|
#ifdef PARANOID
|
|
else {
|
|
signalling = 0;
|
|
EXCEPTION(EX_INTERNAL | 0x113);
|
|
x = &CONST_QNaN;
|
|
}
|
|
#endif /* PARANOID */
|
|
|
|
if (!signalling) {
|
|
if (!(x->sigh & 0x80000000)) /* pseudo-NaN ? */
|
|
x = &CONST_QNaN;
|
|
reg_move(x, dest);
|
|
return;
|
|
}
|
|
if (control_word & CW_Invalid) {
|
|
/* The masked response */
|
|
if (!(x->sigh & 0x80000000)) /* pseudo-NaN ? */
|
|
x = &CONST_QNaN;
|
|
reg_move(x, dest);
|
|
/* ensure a Quiet NaN */
|
|
dest->sigh |= 0x40000000;
|
|
}
|
|
EXCEPTION(EX_Invalid);
|
|
|
|
return;
|
|
}
|
|
/* Invalid arith operation on Valid registers */
|
|
void
|
|
arith_invalid(FPU_REG * dest)
|
|
{
|
|
|
|
if (control_word & CW_Invalid) {
|
|
/* The masked response */
|
|
reg_move(&CONST_QNaN, dest);
|
|
}
|
|
EXCEPTION(EX_Invalid);
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
|
|
/* Divide a finite number by zero */
|
|
void
|
|
divide_by_zero(int sign, FPU_REG * dest)
|
|
{
|
|
|
|
if (control_word & CW_ZeroDiv) {
|
|
/* The masked response */
|
|
reg_move(&CONST_INF, dest);
|
|
dest->sign = (unsigned char) sign;
|
|
}
|
|
EXCEPTION(EX_ZeroDiv);
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
|
|
/* This may be called often, so keep it lean */
|
|
void
|
|
set_precision_flag_up(void)
|
|
{
|
|
if (control_word & CW_Precision)
|
|
status_word |= (SW_Precision | SW_C1); /* The masked response */
|
|
else
|
|
exception(EX_Precision | SW_C1);
|
|
|
|
}
|
|
|
|
|
|
/* This may be called often, so keep it lean */
|
|
void
|
|
set_precision_flag_down(void)
|
|
{
|
|
if (control_word & CW_Precision) { /* The masked response */
|
|
status_word &= ~SW_C1;
|
|
status_word |= SW_Precision;
|
|
} else
|
|
exception(EX_Precision);
|
|
}
|
|
|
|
|
|
int
|
|
denormal_operand(void)
|
|
{
|
|
if (control_word & CW_Denormal) { /* The masked response */
|
|
status_word |= SW_Denorm_Op;
|
|
return 0;
|
|
} else {
|
|
exception(EX_Denormal);
|
|
return 1;
|
|
}
|
|
}
|
|
|
|
|
|
void
|
|
arith_overflow(FPU_REG * dest)
|
|
{
|
|
|
|
if (control_word & CW_Overflow) {
|
|
char sign;
|
|
/* The masked response */
|
|
/* **** The response here depends upon the rounding mode */
|
|
sign = dest->sign;
|
|
reg_move(&CONST_INF, dest);
|
|
dest->sign = sign;
|
|
} else {
|
|
/* Subtract the magic number from the exponent */
|
|
dest->exp -= (3 * (1 << 13));
|
|
}
|
|
|
|
/* By definition, precision is lost. It appears that the roundup bit
|
|
* (C1) is also set by convention. */
|
|
EXCEPTION(EX_Overflow | EX_Precision | SW_C1);
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
|
|
void
|
|
arith_underflow(FPU_REG * dest)
|
|
{
|
|
|
|
if (control_word & CW_Underflow) {
|
|
/* The masked response */
|
|
if (dest->exp <= EXP_UNDER - 63)
|
|
reg_move(&CONST_Z, dest);
|
|
} else {
|
|
/* Add the magic number to the exponent */
|
|
dest->exp += (3 * (1 << 13));
|
|
}
|
|
|
|
EXCEPTION(EX_Underflow);
|
|
|
|
return;
|
|
}
|
|
|
|
|
|
void
|
|
stack_overflow(void)
|
|
{
|
|
|
|
if (control_word & CW_Invalid) {
|
|
/* The masked response */
|
|
top--;
|
|
reg_move(&CONST_QNaN, FPU_st0_ptr = &st(0));
|
|
}
|
|
EXCEPTION(EX_StackOver);
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
|
|
void
|
|
stack_underflow(void)
|
|
{
|
|
|
|
if (control_word & CW_Invalid) {
|
|
/* The masked response */
|
|
reg_move(&CONST_QNaN, FPU_st0_ptr);
|
|
}
|
|
EXCEPTION(EX_StackUnder);
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
|
|
void
|
|
stack_underflow_i(int i)
|
|
{
|
|
|
|
if (control_word & CW_Invalid) {
|
|
/* The masked response */
|
|
reg_move(&CONST_QNaN, &(st(i)));
|
|
}
|
|
EXCEPTION(EX_StackUnder);
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
|
|
void
|
|
stack_underflow_pop(int i)
|
|
{
|
|
|
|
if (control_word & CW_Invalid) {
|
|
/* The masked response */
|
|
reg_move(&CONST_QNaN, &(st(i)));
|
|
pop();
|
|
}
|
|
EXCEPTION(EX_StackUnder);
|
|
|
|
return;
|
|
|
|
}
|