void FPU_copy_to_reg0(FPU_REG const *r, u_char tag)
{
int regnr = top;
regnr &= 7;
reg_copy(r, &st(0));
fpu_tag_word &= ~(3 << (regnr * 2));
fpu_tag_word |= (tag & 3) << (regnr * 2);
}
static void fld_const(FPU_REG const * c, int adj, u_char tag)
{
FPU_REG *st_new_ptr;
if (STACK_OVERFLOW) {
FPU_stack_overflow();
return;
}
push();
reg_copy(c, st_new_ptr);
st_new_ptr->sigl += adj; /* For all our fldxxx constants, we don't need to
borrow or carry. */
FPU_settag0(tag);
clear_C1();
}
static void phineas_rd_n (int n)
{
switch (n)
{
case 0x0: /* 038: RTIME */
reg_copy (c, clock_reg [timer_reg_sel]);
break;
case 0x1: /* 078: RTIMEST */
reg_copy (c, clock_reg [timer_reg_sel]);
/* start correction count ??? */
break;
case 0x2: /* 0b8: RALM */
reg_copy (c, alarm_reg [timer_reg_sel]);
break;
case 0x3: /* 0f8: RSTS */
reg_copy (c, timer_reg_sel ? accuracy_factor : timer_status);
break;
case 0x4: /* 138: RSCR */
reg_copy (c, timer_scratch);
break;
case 0x5: /* 178: RINT */
reg_copy (c, interval_timer);
break;
case 0x6: /* 1b8: ??? */
case 0x7: /* 1f8: ??? */
case 0x8: /* 238: ??? */
case 0x9: /* 278: ??? */
case 0xa: /* 2b8: ??? */
case 0xb: /* 2f8: ??? */
case 0xc: /* 338: ??? */
case 0xd: /* 378: ??? */
case 0xe: /* 3b8: ??? */
case 0xf: /* 3f8: ??? */
reg_zero (c);
break;
}
}
static void fxtract(FPU_REG *st0_ptr, u_char st0_tag)
{
FPU_REG *st_new_ptr;
u_char sign;
register FPU_REG *st1_ptr = st0_ptr;
if (STACK_OVERFLOW) {
FPU_stack_overflow();
return;
}
clear_C1();
if (st0_tag == TAG_Valid) {
long e;
push();
sign = getsign(st1_ptr);
reg_copy(st1_ptr, st_new_ptr);
setexponent16(st_new_ptr, exponent(st_new_ptr));
denormal_arg:
e = exponent16(st_new_ptr);
convert_l2reg(&e, 1);
setexponentpos(st_new_ptr, 0);
setsign(st_new_ptr, sign);
FPU_settag0(TAG_Valid);
return;
} else if (st0_tag == TAG_Zero) {
sign = getsign(st0_ptr);
if (FPU_divide_by_zero(0, SIGN_NEG) < 0)
return;
push();
FPU_copy_to_reg0(&CONST_Z, TAG_Zero);
setsign(st_new_ptr, sign);
return;
}
if (st0_tag == TAG_Special)
st0_tag = FPU_Special(st0_ptr);
if (st0_tag == TW_Denormal) {
if (denormal_operand() < 0)
return;
push();
sign = getsign(st1_ptr);
FPU_to_exp16(st1_ptr, st_new_ptr);
goto denormal_arg;
} else if (st0_tag == TW_Infinity) {
sign = getsign(st0_ptr);
setpositive(st0_ptr);
push();
FPU_copy_to_reg0(&CONST_INF, TAG_Special);
setsign(st_new_ptr, sign);
return;
} else if (st0_tag == TW_NaN) {
if (real_1op_NaN(st0_ptr) < 0)
return;
push();
FPU_copy_to_reg0(st0_ptr, TAG_Special);
return;
} else if (st0_tag == TAG_Empty) {
if (control_word & EX_Invalid) {
FPU_stack_underflow();
push();
FPU_stack_underflow();
} else
EXCEPTION(EX_StackUnder);
}
#ifdef PARANOID
else
EXCEPTION(EX_INTERNAL | 0x119);
#endif
}
static
int add_sub_specials(FPU_REG const *a, u_char taga, u_char signa,
FPU_REG const *b, u_char tagb, u_char signb,
FPU_REG * dest, int deststnr, int control_w)
{
if (((taga == TW_Denormal) || (tagb == TW_Denormal))
&& (denormal_operand() < 0))
return FPU_Exception;
if (taga == TAG_Zero) {
if (tagb == TAG_Zero) {
u_char different_signs = signa ^ signb;
FPU_copy_to_regi(a, TAG_Zero, deststnr);
if (different_signs) {
setsign(dest, ((control_w & CW_RC) != RC_DOWN)
? SIGN_POS : SIGN_NEG);
} else
setsign(dest, signa);
return TAG_Zero;
} else {
reg_copy(b, dest);
if ((tagb == TW_Denormal) && (b->sigh & 0x80000000)) {
addexponent(dest, 1);
tagb = TAG_Valid;
} else if (tagb > TAG_Empty)
tagb = TAG_Special;
setsign(dest, signb);
FPU_settagi(deststnr, tagb);
return tagb;
}
} else if (tagb == TAG_Zero) {
reg_copy(a, dest);
if ((taga == TW_Denormal) && (a->sigh & 0x80000000)) {
addexponent(dest, 1);
taga = TAG_Valid;
} else if (taga > TAG_Empty)
taga = TAG_Special;
setsign(dest, signa);
FPU_settagi(deststnr, taga);
return taga;
} else if (taga == TW_Infinity) {
if ((tagb != TW_Infinity) || (signa == signb)) {
FPU_copy_to_regi(a, TAG_Special, deststnr);
setsign(dest, signa);
return taga;
}
return arith_invalid(deststnr);
} else if (tagb == TW_Infinity) {
FPU_copy_to_regi(b, TAG_Special, deststnr);
setsign(dest, signb);
return tagb;
}
#ifdef PARANOID
EXCEPTION(EX_INTERNAL | 0x101);
#endif
return FPU_Exception;
}
static
int add_sub_specials(FPU_REG const *a, u_char taga, u_char signa,
FPU_REG const *b, u_char tagb, u_char signb,
FPU_REG *dest, int deststnr, int control_w)
{
if ( ((taga == TW_Denormal) || (tagb == TW_Denormal))
&& (denormal_operand() < 0) )
return FPU_Exception;
if (taga == TAG_Zero)
{
if (tagb == TAG_Zero)
{
/* Both are zero, result will be zero. */
u_char different_signs = signa ^ signb;
FPU_copy_to_regi(a, TAG_Zero, deststnr);
if ( different_signs )
{
/* Signs are different. */
/* Sign of answer depends upon rounding mode. */
setsign(dest, ((control_w & CW_RC) != RC_DOWN)
? SIGN_POS : SIGN_NEG);
}
else
setsign(dest, signa); /* signa may differ from the sign of a. */
return TAG_Zero;
}
else
{
reg_copy(b, dest);
if ( (tagb == TW_Denormal) && (b->sigh & 0x80000000) )
{
/* A pseudoDenormal, convert it. */
addexponent(dest, 1);
tagb = TAG_Valid;
}
else if ( tagb > TAG_Empty )
tagb = TAG_Special;
setsign(dest, signb); /* signb may differ from the sign of b. */
FPU_settagi(deststnr, tagb);
return tagb;
}
}
else if (tagb == TAG_Zero)
{
reg_copy(a, dest);
if ( (taga == TW_Denormal) && (a->sigh & 0x80000000) )
{
/* A pseudoDenormal */
addexponent(dest, 1);
taga = TAG_Valid;
}
else if ( taga > TAG_Empty )
taga = TAG_Special;
setsign(dest, signa); /* signa may differ from the sign of a. */
FPU_settagi(deststnr, taga);
return taga;
}
else if (taga == TW_Infinity)
{
if ( (tagb != TW_Infinity) || (signa == signb) )
{
FPU_copy_to_regi(a, TAG_Special, deststnr);
setsign(dest, signa); /* signa may differ from the sign of a. */
return taga;
}
/* Infinity-Infinity is undefined. */
return arith_invalid(deststnr);
}
else if (tagb == TW_Infinity)
{
FPU_copy_to_regi(b, TAG_Special, deststnr);
setsign(dest, signb); /* signb may differ from the sign of b. */
return tagb;
}
#ifdef PARANOID
EXCEPTION(EX_INTERNAL|0x101);
#endif
return FPU_Exception;
}
static void phineas_wr_n (int n)
{
switch (n)
{
case 0x0: /* 028: WTIME write C to clock register */
reg_copy (clock_reg [timer_reg_sel], c);
clock_decr [timer_reg_sel] = 0;
break;
case 0x1: /* 068: WTIME- write C to clock register and set to decr */
reg_copy (clock_reg [timer_reg_sel], c);
clock_decr [timer_reg_sel]= 1;
break;
case 0x2: /* 0a8: WALM write C to alarm register */
reg_copy (alarm_reg [timer_reg_sel], c);
break;
case 0x3: /* 0e8: WSTS */
reg_copy (timer_reg_sel ? accuracy_factor : timer_status, c);
break;
case 0x4: /* 128: WSCR write C to scratch register */
reg_copy (timer_scratch, c);
break;
case 0x5: /* 168: WINTST write C to interval timer and start */
reg_copy (interval_timer, c);
interval_running = 1;
break;
case 0x6: /* 1a8: ??? */
break;
case 0x7: /* 1e8: STPINT stop interval timer */
interval_running = 0;
break;
case 0x8: /* 228: WKUPOFF */
if (timer_reg_sel == TIMER_A)
sec_wakeup = 0;
else
min_wakeup = 0;
break;
case 0x9: /* 268: WKUPON */ break;
if (timer_reg_sel == TIMER_A)
sec_wakeup = 1;
else
min_wakeup = 1;
break;
case 0xa: /* 2a8: ALMOFF */
alarm_enable [timer_reg_sel] = 0;
break;
case 0xb: /* 2e8: ALMON */
alarm_enable [timer_reg_sel] = 1;
break;
case 0xc: /* 328: STOPC */
clock_enable [timer_reg_sel] = 0;
break;
case 0xd: /* 368: STARTC */
clock_enable [timer_reg_sel] = 1;
break;
case 0xe: /* 3a8: TIMER=A */
timer_reg_sel = TIMER_A;
break;
case 0xf: /* 3e8: TIMER=B */
timer_reg_sel = TIMER_B;
break;
}
}
/*
Divide one register by another and put the result into a third register.
*/
int FPU_div(int flags, int rm, int control_w)
{
FPU_REG x, y;
FPU_REG const *a, *b, *st0_ptr, *st_ptr;
FPU_REG *dest;
u_char taga, tagb, signa, signb, sign, saved_sign;
int tag, deststnr;
if (flags & DEST_RM)
deststnr = rm;
else
deststnr = 0;
if (flags & REV) {
b = &st(0);
st0_ptr = b;
tagb = FPU_gettag0();
if (flags & LOADED) {
a = (FPU_REG *) rm;
taga = flags & 0x0f;
} else {
a = &st(rm);
st_ptr = a;
taga = FPU_gettagi(rm);
}
} else {
a = &st(0);
st0_ptr = a;
taga = FPU_gettag0();
if (flags & LOADED) {
b = (FPU_REG *) rm;
tagb = flags & 0x0f;
} else {
b = &st(rm);
st_ptr = b;
tagb = FPU_gettagi(rm);
}
}
signa = getsign(a);
signb = getsign(b);
sign = signa ^ signb;
dest = &st(deststnr);
saved_sign = getsign(dest);
if (!(taga | tagb)) {
/* Both regs Valid, this should be the most common case. */
reg_copy(a, &x);
reg_copy(b, &y);
setpositive(&x);
setpositive(&y);
tag = FPU_u_div(&x, &y, dest, control_w, sign);
if (tag < 0)
return tag;
FPU_settagi(deststnr, tag);
return tag;
}
if (taga == TAG_Special)
taga = FPU_Special(a);
if (tagb == TAG_Special)
tagb = FPU_Special(b);
if (((taga == TAG_Valid) && (tagb == TW_Denormal))
|| ((taga == TW_Denormal) && (tagb == TAG_Valid))
|| ((taga == TW_Denormal) && (tagb == TW_Denormal))) {
if (denormal_operand() < 0)
return FPU_Exception;
FPU_to_exp16(a, &x);
FPU_to_exp16(b, &y);
tag = FPU_u_div(&x, &y, dest, control_w, sign);
if (tag < 0)
return tag;
FPU_settagi(deststnr, tag);
return tag;
} else if ((taga <= TW_Denormal) && (tagb <= TW_Denormal)) {
if (tagb != TAG_Zero) {
/* Want to find Zero/Valid */
if (tagb == TW_Denormal) {
if (denormal_operand() < 0)
return FPU_Exception;
}
/* The result is zero. */
FPU_copy_to_regi(&CONST_Z, TAG_Zero, deststnr);
setsign(dest, sign);
return TAG_Zero;
}
/* We have an exception condition, either 0/0 or Valid/Zero. */
if (taga == TAG_Zero) {
/* 0/0 */
return arith_invalid(deststnr);
}
/* Valid/Zero */
return FPU_divide_by_zero(deststnr, sign);
}
/* Must have infinities, NaNs, etc */
else if ((taga == TW_NaN) || (tagb == TW_NaN)) {
if (flags & LOADED)
return real_2op_NaN((FPU_REG *) rm, flags & 0x0f, 0,
st0_ptr);
if (flags & DEST_RM) {
int tag;
tag = FPU_gettag0();
if (tag == TAG_Special)
tag = FPU_Special(st0_ptr);
return real_2op_NaN(st0_ptr, tag, rm,
(flags & REV) ? st0_ptr : &st(rm));
} else {
int tag;
tag = FPU_gettagi(rm);
if (tag == TAG_Special)
tag = FPU_Special(&st(rm));
return real_2op_NaN(&st(rm), tag, 0,
(flags & REV) ? st0_ptr : &st(rm));
}
} else if (taga == TW_Infinity) {
if (tagb == TW_Infinity) {
/* infinity/infinity */
return arith_invalid(deststnr);
} else {
/* tagb must be Valid or Zero */
if ((tagb == TW_Denormal) && (denormal_operand() < 0))
return FPU_Exception;
/* Infinity divided by Zero or Valid does
not raise and exception, but returns Infinity */
FPU_copy_to_regi(a, TAG_Special, deststnr);
setsign(dest, sign);
return taga;
}
} else if (tagb == TW_Infinity) {
if ((taga == TW_Denormal) && (denormal_operand() < 0))
return FPU_Exception;
/* The result is zero. */
FPU_copy_to_regi(&CONST_Z, TAG_Zero, deststnr);
setsign(dest, sign);
return TAG_Zero;
}
#ifdef PARANOID
else {
EXCEPTION(EX_INTERNAL | 0x102);
return FPU_Exception;
}
#endif /* PARANOID */
return 0;
}
void FPU_copy_to_reg1(FPU_REG const *r, u_char tag)
{
reg_copy(r, &st(1));
FPU_settagi(1, tag);
}
void FPU_copy_to_regi(FPU_REG const *r, u_char tag, int stnr)
{
reg_copy(r, &st(stnr));
FPU_settagi(stnr, tag);
}
int FPU_div(int flags, int rm, int control_w)
{
FPU_REG x, y;
FPU_REG const *a, *b, *st0_ptr, *st_ptr;
FPU_REG *dest;
u_char taga, tagb, signa, signb, sign, saved_sign;
int tag, deststnr;
if (flags & DEST_RM)
deststnr = rm;
else
deststnr = 0;
if (flags & REV) {
b = &st(0);
st0_ptr = b;
tagb = FPU_gettag0();
if (flags & LOADED) {
a = (FPU_REG *) rm;
taga = flags & 0x0f;
} else {
a = &st(rm);
st_ptr = a;
taga = FPU_gettagi(rm);
}
} else {
a = &st(0);
st0_ptr = a;
taga = FPU_gettag0();
if (flags & LOADED) {
b = (FPU_REG *) rm;
tagb = flags & 0x0f;
} else {
b = &st(rm);
st_ptr = b;
tagb = FPU_gettagi(rm);
}
}
signa = getsign(a);
signb = getsign(b);
sign = signa ^ signb;
dest = &st(deststnr);
saved_sign = getsign(dest);
if (!(taga | tagb)) {
reg_copy(a, &x);
reg_copy(b, &y);
setpositive(&x);
setpositive(&y);
tag = FPU_u_div(&x, &y, dest, control_w, sign);
if (tag < 0)
return tag;
FPU_settagi(deststnr, tag);
return tag;
}
if (taga == TAG_Special)
taga = FPU_Special(a);
if (tagb == TAG_Special)
tagb = FPU_Special(b);
if (((taga == TAG_Valid) && (tagb == TW_Denormal))
|| ((taga == TW_Denormal) && (tagb == TAG_Valid))
|| ((taga == TW_Denormal) && (tagb == TW_Denormal))) {
if (denormal_operand() < 0)
return FPU_Exception;
FPU_to_exp16(a, &x);
FPU_to_exp16(b, &y);
tag = FPU_u_div(&x, &y, dest, control_w, sign);
if (tag < 0)
return tag;
FPU_settagi(deststnr, tag);
return tag;
} else if ((taga <= TW_Denormal) && (tagb <= TW_Denormal)) {
if (tagb != TAG_Zero) {
if (tagb == TW_Denormal) {
if (denormal_operand() < 0)
return FPU_Exception;
}
FPU_copy_to_regi(&CONST_Z, TAG_Zero, deststnr);
setsign(dest, sign);
return TAG_Zero;
}
if (taga == TAG_Zero) {
return arith_invalid(deststnr);
}
return FPU_divide_by_zero(deststnr, sign);
}
else if ((taga == TW_NaN) || (tagb == TW_NaN)) {
if (flags & LOADED)
return real_2op_NaN((FPU_REG *) rm, flags & 0x0f, 0,
st0_ptr);
if (flags & DEST_RM) {
int tag;
tag = FPU_gettag0();
if (tag == TAG_Special)
tag = FPU_Special(st0_ptr);
return real_2op_NaN(st0_ptr, tag, rm,
(flags & REV) ? st0_ptr : &st(rm));
} else {
int tag;
tag = FPU_gettagi(rm);
if (tag == TAG_Special)
tag = FPU_Special(&st(rm));
return real_2op_NaN(&st(rm), tag, 0,
(flags & REV) ? st0_ptr : &st(rm));
}
} else if (taga == TW_Infinity) {
if (tagb == TW_Infinity) {
return arith_invalid(deststnr);
} else {
if ((tagb == TW_Denormal) && (denormal_operand() < 0))
return FPU_Exception;
FPU_copy_to_regi(a, TAG_Special, deststnr);
setsign(dest, sign);
return taga;
}
} else if (tagb == TW_Infinity) {
if ((taga == TW_Denormal) && (denormal_operand() < 0))
return FPU_Exception;
FPU_copy_to_regi(&CONST_Z, TAG_Zero, deststnr);
setsign(dest, sign);
return TAG_Zero;
}
#ifdef PARANOID
else {
EXCEPTION(EX_INTERNAL | 0x102);
return FPU_Exception;
}
#endif
return 0;
}
