diff options
Diffstat (limited to 'arch/x86/math-emu/reg_ld_str.c')
| -rw-r--r-- | arch/x86/math-emu/reg_ld_str.c | 1220 |
1 files changed, 1220 insertions, 0 deletions
diff --git a/arch/x86/math-emu/reg_ld_str.c b/arch/x86/math-emu/reg_ld_str.c new file mode 100644 index 000000000..d40ff4549 --- /dev/null +++ b/arch/x86/math-emu/reg_ld_str.c @@ -0,0 +1,1220 @@ +// SPDX-License-Identifier: GPL-2.0 +/*---------------------------------------------------------------------------+ + | reg_ld_str.c | + | | + | All of the functions which transfer data between user memory and FPU_REGs.| + | | + | Copyright (C) 1992,1993,1994,1996,1997 | + | W. Metzenthen, 22 Parker St, Ormond, Vic 3163, Australia | + | E-mail billm@suburbia.net | + | | + | | + +---------------------------------------------------------------------------*/ + +/*---------------------------------------------------------------------------+ + | 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 "fpu_emu.h" + +#include <linux/uaccess.h> + +#include "fpu_system.h" +#include "exception.h" +#include "reg_constant.h" +#include "control_w.h" +#include "status_w.h" + +#define DOUBLE_Emax 1023 /* largest valid exponent */ +#define DOUBLE_Ebias 1023 +#define DOUBLE_Emin (-1022) /* smallest valid exponent */ + +#define SINGLE_Emax 127 /* largest valid exponent */ +#define SINGLE_Ebias 127 +#define SINGLE_Emin (-126) /* smallest valid exponent */ + +static u_char normalize_no_excep(FPU_REG *r, int exp, int sign) +{ + u_char tag; + + setexponent16(r, exp); + + tag = FPU_normalize_nuo(r); + stdexp(r); + if (sign) + setnegative(r); + + return tag; +} + +int FPU_tagof(FPU_REG *ptr) +{ + int exp; + + exp = exponent16(ptr) & 0x7fff; + if (exp == 0) { + if (!(ptr->sigh | ptr->sigl)) { + return TAG_Zero; + } + /* The number is a de-normal or pseudodenormal. */ + return TAG_Special; + } + + if (exp == 0x7fff) { + /* Is an Infinity, a NaN, or an unsupported data type. */ + return TAG_Special; + } + + if (!(ptr->sigh & 0x80000000)) { + /* Unsupported data type. */ + /* Valid numbers have the ms bit set to 1. */ + /* Unnormal. */ + return TAG_Special; + } + + return TAG_Valid; +} + +/* Get a long double from user memory */ +int FPU_load_extended(long double __user *s, int stnr) +{ + FPU_REG *sti_ptr = &st(stnr); + + RE_ENTRANT_CHECK_OFF; + FPU_access_ok(VERIFY_READ, s, 10); + __copy_from_user(sti_ptr, s, 10); + RE_ENTRANT_CHECK_ON; + + return FPU_tagof(sti_ptr); +} + +/* Get a double from user memory */ +int FPU_load_double(double __user *dfloat, FPU_REG *loaded_data) +{ + int exp, tag, negative; + unsigned m64, l64; + + RE_ENTRANT_CHECK_OFF; + FPU_access_ok(VERIFY_READ, dfloat, 8); + FPU_get_user(m64, 1 + (unsigned long __user *)dfloat); + FPU_get_user(l64, (unsigned long __user *)dfloat); + RE_ENTRANT_CHECK_ON; + + negative = (m64 & 0x80000000) ? SIGN_Negative : SIGN_Positive; + exp = ((m64 & 0x7ff00000) >> 20) - DOUBLE_Ebias + EXTENDED_Ebias; + m64 &= 0xfffff; + if (exp > DOUBLE_Emax + EXTENDED_Ebias) { + /* Infinity or NaN */ + if ((m64 == 0) && (l64 == 0)) { + /* +- infinity */ + loaded_data->sigh = 0x80000000; + loaded_data->sigl = 0x00000000; + exp = EXP_Infinity + EXTENDED_Ebias; + tag = TAG_Special; + } else { + /* Must be a signaling or quiet NaN */ + exp = EXP_NaN + EXTENDED_Ebias; + loaded_data->sigh = (m64 << 11) | 0x80000000; + loaded_data->sigh |= l64 >> 21; + loaded_data->sigl = l64 << 11; + tag = TAG_Special; /* The calling function must look for NaNs */ + } + } else if (exp < DOUBLE_Emin + EXTENDED_Ebias) { + /* Zero or de-normal */ + if ((m64 == 0) && (l64 == 0)) { + /* Zero */ + reg_copy(&CONST_Z, loaded_data); + exp = 0; + tag = TAG_Zero; + } else { + /* De-normal */ + loaded_data->sigh = m64 << 11; + loaded_data->sigh |= l64 >> 21; + loaded_data->sigl = l64 << 11; + + return normalize_no_excep(loaded_data, DOUBLE_Emin, + negative) + | (denormal_operand() < 0 ? FPU_Exception : 0); + } + } else { + loaded_data->sigh = (m64 << 11) | 0x80000000; + loaded_data->sigh |= l64 >> 21; + loaded_data->sigl = l64 << 11; + + tag = TAG_Valid; + } + + setexponent16(loaded_data, exp | negative); + + return tag; +} + +/* Get a float from user memory */ +int FPU_load_single(float __user *single, FPU_REG *loaded_data) +{ + unsigned m32; + int exp, tag, negative; + + RE_ENTRANT_CHECK_OFF; + FPU_access_ok(VERIFY_READ, single, 4); + FPU_get_user(m32, (unsigned long __user *)single); + RE_ENTRANT_CHECK_ON; + + negative = (m32 & 0x80000000) ? SIGN_Negative : SIGN_Positive; + + if (!(m32 & 0x7fffffff)) { + /* Zero */ + reg_copy(&CONST_Z, loaded_data); + addexponent(loaded_data, negative); + return TAG_Zero; + } + exp = ((m32 & 0x7f800000) >> 23) - SINGLE_Ebias + EXTENDED_Ebias; + m32 = (m32 & 0x7fffff) << 8; + if (exp < SINGLE_Emin + EXTENDED_Ebias) { + /* De-normals */ + loaded_data->sigh = m32; + loaded_data->sigl = 0; + + return normalize_no_excep(loaded_data, SINGLE_Emin, negative) + | (denormal_operand() < 0 ? FPU_Exception : 0); + } else if (exp > SINGLE_Emax + EXTENDED_Ebias) { + /* Infinity or NaN */ + if (m32 == 0) { + /* +- infinity */ + loaded_data->sigh = 0x80000000; + loaded_data->sigl = 0x00000000; + exp = EXP_Infinity + EXTENDED_Ebias; + tag = TAG_Special; + } else { + /* Must be a signaling or quiet NaN */ + exp = EXP_NaN + EXTENDED_Ebias; + loaded_data->sigh = m32 | 0x80000000; + loaded_data->sigl = 0; + tag = TAG_Special; /* The calling function must look for NaNs */ + } + } else { + loaded_data->sigh = m32 | 0x80000000; + loaded_data->sigl = 0; + tag = TAG_Valid; + } + + setexponent16(loaded_data, exp | negative); /* Set the sign. */ + + return tag; +} + +/* Get a long long from user memory */ +int FPU_load_int64(long long __user *_s) +{ + long long s; + int sign; + FPU_REG *st0_ptr = &st(0); + + RE_ENTRANT_CHECK_OFF; + FPU_access_ok(VERIFY_READ, _s, 8); + if (copy_from_user(&s, _s, 8)) + FPU_abort; + RE_ENTRANT_CHECK_ON; + + if (s == 0) { + reg_copy(&CONST_Z, st0_ptr); + return TAG_Zero; + } + + if (s > 0) + sign = SIGN_Positive; + else { + s = -s; + sign = SIGN_Negative; + } + + significand(st0_ptr) = s; + + return normalize_no_excep(st0_ptr, 63, sign); +} + +/* Get a long from user memory */ +int FPU_load_int32(long __user *_s, FPU_REG *loaded_data) +{ + long s; + int negative; + + RE_ENTRANT_CHECK_OFF; + FPU_access_ok(VERIFY_READ, _s, 4); + FPU_get_user(s, _s); + RE_ENTRANT_CHECK_ON; + + if (s == 0) { + reg_copy(&CONST_Z, loaded_data); + return TAG_Zero; + } + + if (s > 0) + negative = SIGN_Positive; + else { + s = -s; + negative = SIGN_Negative; + } + + loaded_data->sigh = s; + loaded_data->sigl = 0; + + return normalize_no_excep(loaded_data, 31, negative); +} + +/* Get a short from user memory */ +int FPU_load_int16(short __user *_s, FPU_REG *loaded_data) +{ + int s, negative; + + RE_ENTRANT_CHECK_OFF; + FPU_access_ok(VERIFY_READ, _s, 2); + /* Cast as short to get the sign extended. */ + FPU_get_user(s, _s); + RE_ENTRANT_CHECK_ON; + + if (s == 0) { + reg_copy(&CONST_Z, loaded_data); + return TAG_Zero; + } + + if (s > 0) + negative = SIGN_Positive; + else { + s = -s; + negative = SIGN_Negative; + } + + loaded_data->sigh = s << 16; + loaded_data->sigl = 0; + + return normalize_no_excep(loaded_data, 15, negative); +} + +/* Get a packed bcd array from user memory */ +int FPU_load_bcd(u_char __user *s) +{ + FPU_REG *st0_ptr = &st(0); + int pos; + u_char bcd; + long long l = 0; + int sign; + + RE_ENTRANT_CHECK_OFF; + FPU_access_ok(VERIFY_READ, s, 10); + RE_ENTRANT_CHECK_ON; + for (pos = 8; pos >= 0; pos--) { + l *= 10; + RE_ENTRANT_CHECK_OFF; + FPU_get_user(bcd, s + pos); + RE_ENTRANT_CHECK_ON; + l += bcd >> 4; + l *= 10; + l += bcd & 0x0f; + } + + RE_ENTRANT_CHECK_OFF; + FPU_get_user(sign, s + 9); + sign = sign & 0x80 ? SIGN_Negative : SIGN_Positive; + RE_ENTRANT_CHECK_ON; + + if (l == 0) { + reg_copy(&CONST_Z, st0_ptr); + addexponent(st0_ptr, sign); /* Set the sign. */ + return TAG_Zero; + } else { + significand(st0_ptr) = l; + return normalize_no_excep(st0_ptr, 63, sign); + } +} + +/*===========================================================================*/ + +/* Put a long double into user memory */ +int FPU_store_extended(FPU_REG *st0_ptr, u_char st0_tag, + long double __user * d) +{ + /* + The only exception raised by an attempt to store to an + extended format is the Invalid Stack exception, i.e. + attempting to store from an empty register. + */ + + if (st0_tag != TAG_Empty) { + RE_ENTRANT_CHECK_OFF; + FPU_access_ok(VERIFY_WRITE, d, 10); + + FPU_put_user(st0_ptr->sigl, (unsigned long __user *)d); + FPU_put_user(st0_ptr->sigh, + (unsigned long __user *)((u_char __user *) d + 4)); + FPU_put_user(exponent16(st0_ptr), + (unsigned short __user *)((u_char __user *) d + + 8)); + RE_ENTRANT_CHECK_ON; + + return 1; + } + + /* Empty register (stack underflow) */ + EXCEPTION(EX_StackUnder); + if (control_word & CW_Invalid) { + /* The masked response */ + /* Put out the QNaN indefinite */ + RE_ENTRANT_CHECK_OFF; + FPU_access_ok(VERIFY_WRITE, d, 10); + FPU_put_user(0, (unsigned long __user *)d); + FPU_put_user(0xc0000000, 1 + (unsigned long __user *)d); + FPU_put_user(0xffff, 4 + (short __user *)d); + RE_ENTRANT_CHECK_ON; + return 1; + } else + return 0; + +} + +/* Put a double into user memory */ +int FPU_store_double(FPU_REG *st0_ptr, u_char st0_tag, double __user *dfloat) +{ + unsigned long l[2]; + unsigned long increment = 0; /* avoid gcc warnings */ + int precision_loss; + int exp; + FPU_REG tmp; + + l[0] = 0; + l[1] = 0; + if (st0_tag == TAG_Valid) { + reg_copy(st0_ptr, &tmp); + exp = exponent(&tmp); + + if (exp < DOUBLE_Emin) { /* It may be a denormal */ + addexponent(&tmp, -DOUBLE_Emin + 52); /* largest exp to be 51 */ +denormal_arg: + if ((precision_loss = FPU_round_to_int(&tmp, st0_tag))) { +#ifdef PECULIAR_486 + /* Did it round to a non-denormal ? */ + /* This behaviour might be regarded as peculiar, it appears + that the 80486 rounds to the dest precision, then + converts to decide underflow. */ + if (! + ((tmp.sigh == 0x00100000) && (tmp.sigl == 0) + && (st0_ptr->sigl & 0x000007ff))) +#endif /* PECULIAR_486 */ + { + EXCEPTION(EX_Underflow); + /* This is a special case: see sec 16.2.5.1 of + the 80486 book */ + if (!(control_word & CW_Underflow)) + return 0; + } + EXCEPTION(precision_loss); + if (!(control_word & CW_Precision)) + return 0; + } + l[0] = tmp.sigl; + l[1] = tmp.sigh; + } else { + if (tmp.sigl & 0x000007ff) { + precision_loss = 1; + switch (control_word & CW_RC) { + case RC_RND: + /* Rounding can get a little messy.. */ + increment = ((tmp.sigl & 0x7ff) > 0x400) | /* nearest */ + ((tmp.sigl & 0xc00) == 0xc00); /* odd -> even */ + break; + case RC_DOWN: /* towards -infinity */ + increment = + signpositive(&tmp) ? 0 : tmp. + sigl & 0x7ff; + break; + case RC_UP: /* towards +infinity */ + increment = + signpositive(&tmp) ? tmp. + sigl & 0x7ff : 0; + break; + case RC_CHOP: + increment = 0; + break; + } + + /* Truncate the mantissa */ + tmp.sigl &= 0xfffff800; + + if (increment) { + if (tmp.sigl >= 0xfffff800) { + /* the sigl part overflows */ + if (tmp.sigh == 0xffffffff) { + /* The sigh part overflows */ + tmp.sigh = 0x80000000; + exp++; + if (exp >= EXP_OVER) + goto overflow; + } else { + tmp.sigh++; + } + tmp.sigl = 0x00000000; + } else { + /* We only need to increment sigl */ + tmp.sigl += 0x00000800; + } + } + } else + precision_loss = 0; + + l[0] = (tmp.sigl >> 11) | (tmp.sigh << 21); + l[1] = ((tmp.sigh >> 11) & 0xfffff); + + if (exp > DOUBLE_Emax) { + overflow: + EXCEPTION(EX_Overflow); + if (!(control_word & CW_Overflow)) + return 0; + set_precision_flag_up(); + if (!(control_word & CW_Precision)) + return 0; + + /* This is a special case: see sec 16.2.5.1 of the 80486 book */ + /* Overflow to infinity */ + l[1] = 0x7ff00000; /* Set to + INF */ + } else { + if (precision_loss) { + if (increment) + set_precision_flag_up(); + else + set_precision_flag_down(); + } + /* Add the exponent */ + l[1] |= (((exp + DOUBLE_Ebias) & 0x7ff) << 20); + } + } + } else if (st0_tag == TAG_Zero) { + /* Number is zero */ + } else if (st0_tag == TAG_Special) { + st0_tag = FPU_Special(st0_ptr); + if (st0_tag == TW_Denormal) { + /* A denormal will always underflow. */ +#ifndef PECULIAR_486 + /* An 80486 is supposed to be able to generate + a denormal exception here, but... */ + /* Underflow has priority. */ + if (control_word & CW_Underflow) + denormal_operand(); +#endif /* PECULIAR_486 */ + reg_copy(st0_ptr, &tmp); + goto denormal_arg; + } else if (st0_tag == TW_Infinity) { + l[1] = 0x7ff00000; + } else if (st0_tag == TW_NaN) { + /* Is it really a NaN ? */ + if ((exponent(st0_ptr) == EXP_OVER) + && (st0_ptr->sigh & 0x80000000)) { + /* See if we can get a valid NaN from the FPU_REG */ + l[0] = + (st0_ptr->sigl >> 11) | (st0_ptr-> + sigh << 21); + l[1] = ((st0_ptr->sigh >> 11) & 0xfffff); + if (!(st0_ptr->sigh & 0x40000000)) { + /* It is a signalling NaN */ + EXCEPTION(EX_Invalid); + if (!(control_word & CW_Invalid)) + return 0; + l[1] |= (0x40000000 >> 11); + } + l[1] |= 0x7ff00000; + } else { + /* It is an unsupported data type */ + EXCEPTION(EX_Invalid); + if (!(control_word & CW_Invalid)) + return 0; + l[1] = 0xfff80000; + } + } + } else if (st0_tag == TAG_Empty) { + /* Empty register (stack underflow) */ + EXCEPTION(EX_StackUnder); + if (control_word & CW_Invalid) { + /* The masked response */ + /* Put out the QNaN indefinite */ + RE_ENTRANT_CHECK_OFF; + FPU_access_ok(VERIFY_WRITE, dfloat, 8); + FPU_put_user(0, (unsigned long __user *)dfloat); + FPU_put_user(0xfff80000, + 1 + (unsigned long __user *)dfloat); + RE_ENTRANT_CHECK_ON; + return 1; + } else + return 0; + } + if (getsign(st0_ptr)) + l[1] |= 0x80000000; + + RE_ENTRANT_CHECK_OFF; + FPU_access_ok(VERIFY_WRITE, dfloat, 8); + FPU_put_user(l[0], (unsigned long __user *)dfloat); + FPU_put_user(l[1], 1 + (unsigned long __user *)dfloat); + RE_ENTRANT_CHECK_ON; + + return 1; +} + +/* Put a float into user memory */ +int FPU_store_single(FPU_REG *st0_ptr, u_char st0_tag, float __user *single) +{ + long templ = 0; + unsigned long increment = 0; /* avoid gcc warnings */ + int precision_loss; + int exp; + FPU_REG tmp; + + if (st0_tag == TAG_Valid) { + + reg_copy(st0_ptr, &tmp); + exp = exponent(&tmp); + + if (exp < SINGLE_Emin) { + addexponent(&tmp, -SINGLE_Emin + 23); /* largest exp to be 22 */ + + denormal_arg: + + if ((precision_loss = FPU_round_to_int(&tmp, st0_tag))) { +#ifdef PECULIAR_486 + /* Did it round to a non-denormal ? */ + /* This behaviour might be regarded as peculiar, it appears + that the 80486 rounds to the dest precision, then + converts to decide underflow. */ + if (!((tmp.sigl == 0x00800000) && + ((st0_ptr->sigh & 0x000000ff) + || st0_ptr->sigl))) +#endif /* PECULIAR_486 */ + { + EXCEPTION(EX_Underflow); + /* This is a special case: see sec 16.2.5.1 of + the 80486 book */ + if (!(control_word & CW_Underflow)) + return 0; + } + EXCEPTION(precision_loss); + if (!(control_word & CW_Precision)) + return 0; + } + templ = tmp.sigl; + } else { + if (tmp.sigl | (tmp.sigh & 0x000000ff)) { + unsigned long sigh = tmp.sigh; + unsigned long sigl = tmp.sigl; + + precision_loss = 1; + switch (control_word & CW_RC) { + case RC_RND: + increment = ((sigh & 0xff) > 0x80) /* more than half */ + ||(((sigh & 0xff) == 0x80) && sigl) /* more than half */ + ||((sigh & 0x180) == 0x180); /* round to even */ + break; + case RC_DOWN: /* towards -infinity */ + increment = signpositive(&tmp) + ? 0 : (sigl | (sigh & 0xff)); + break; + case RC_UP: /* towards +infinity */ + increment = signpositive(&tmp) + ? (sigl | (sigh & 0xff)) : 0; + break; + case RC_CHOP: + increment = 0; + break; + } + + /* Truncate part of the mantissa */ + tmp.sigl = 0; + + if (increment) { + if (sigh >= 0xffffff00) { + /* The sigh part overflows */ + tmp.sigh = 0x80000000; + exp++; + if (exp >= EXP_OVER) + goto overflow; + } else { + tmp.sigh &= 0xffffff00; + tmp.sigh += 0x100; + } + } else { + tmp.sigh &= 0xffffff00; /* Finish the truncation */ + } + } else + precision_loss = 0; + + templ = (tmp.sigh >> 8) & 0x007fffff; + + if (exp > SINGLE_Emax) { + overflow: + EXCEPTION(EX_Overflow); + if (!(control_word & CW_Overflow)) + return 0; + set_precision_flag_up(); + if (!(control_word & CW_Precision)) + return 0; + + /* This is a special case: see sec 16.2.5.1 of the 80486 book. */ + /* Masked response is overflow to infinity. */ + templ = 0x7f800000; + } else { + if (precision_loss) { + if (increment) + set_precision_flag_up(); + else + set_precision_flag_down(); + } + /* Add the exponent */ + templ |= ((exp + SINGLE_Ebias) & 0xff) << 23; + } + } + } else if (st0_tag == TAG_Zero) { + templ = 0; + } else if (st0_tag == TAG_Special) { + st0_tag = FPU_Special(st0_ptr); + if (st0_tag == TW_Denormal) { + reg_copy(st0_ptr, &tmp); + + /* A denormal will always underflow. */ +#ifndef PECULIAR_486 + /* An 80486 is supposed to be able to generate + a denormal exception here, but... */ + /* Underflow has priority. */ + if (control_word & CW_Underflow) + denormal_operand(); +#endif /* PECULIAR_486 */ + goto denormal_arg; + } else if (st0_tag == TW_Infinity) { + templ = 0x7f800000; + } else if (st0_tag == TW_NaN) { + /* Is it really a NaN ? */ + if ((exponent(st0_ptr) == EXP_OVER) + && (st0_ptr->sigh & 0x80000000)) { + /* See if we can get a valid NaN from the FPU_REG */ + templ = st0_ptr->sigh >> 8; + if (!(st0_ptr->sigh & 0x40000000)) { + /* It is a signalling NaN */ + EXCEPTION(EX_Invalid); + if (!(control_word & CW_Invalid)) + return 0; + templ |= (0x40000000 >> 8); + } + templ |= 0x7f800000; + } else { + /* It is an unsupported data type */ + EXCEPTION(EX_Invalid); + if (!(control_word & CW_Invalid)) + return 0; + templ = 0xffc00000; + } + } +#ifdef PARANOID + else { + EXCEPTION(EX_INTERNAL | 0x164); + return 0; + } +#endif + } else if (st0_tag == TAG_Empty) { + /* Empty register (stack underflow) */ + EXCEPTION(EX_StackUnder); + if (control_word & EX_Invalid) { + /* The masked response */ + /* Put out the QNaN indefinite */ + RE_ENTRANT_CHECK_OFF; + FPU_access_ok(VERIFY_WRITE, single, 4); + FPU_put_user(0xffc00000, + (unsigned long __user *)single); + RE_ENTRANT_CHECK_ON; + return 1; + } else + return 0; + } +#ifdef PARANOID + else { + EXCEPTION(EX_INTERNAL | 0x163); + return 0; + } +#endif + if (getsign(st0_ptr)) + templ |= 0x80000000; + + RE_ENTRANT_CHECK_OFF; + FPU_access_ok(VERIFY_WRITE, single, 4); + FPU_put_user(templ, (unsigned long __user *)single); + RE_ENTRANT_CHECK_ON; + + return 1; +} + +/* Put a long long into user memory */ +int FPU_store_int64(FPU_REG *st0_ptr, u_char st0_tag, long long __user *d) +{ + FPU_REG t; + long long tll; + int precision_loss; + + if (st0_tag == TAG_Empty) { + /* Empty register (stack underflow) */ + EXCEPTION(EX_StackUnder); + goto invalid_operand; + } else if (st0_tag == TAG_Special) { + st0_tag = FPU_Special(st0_ptr); + if ((st0_tag == TW_Infinity) || (st0_tag == TW_NaN)) { + EXCEPTION(EX_Invalid); + goto invalid_operand; + } + } + + reg_copy(st0_ptr, &t); + precision_loss = FPU_round_to_int(&t, st0_tag); + ((long *)&tll)[0] = t.sigl; + ((long *)&tll)[1] = t.sigh; + if ((precision_loss == 1) || + ((t.sigh & 0x80000000) && + !((t.sigh == 0x80000000) && (t.sigl == 0) && signnegative(&t)))) { + EXCEPTION(EX_Invalid); + /* This is a special case: see sec 16.2.5.1 of the 80486 book */ + invalid_operand: + if (control_word & EX_Invalid) { + /* Produce something like QNaN "indefinite" */ + tll = 0x8000000000000000LL; + } else + return 0; + } else { + if (precision_loss) + set_precision_flag(precision_loss); + if (signnegative(&t)) + tll = -tll; + } + + RE_ENTRANT_CHECK_OFF; + FPU_access_ok(VERIFY_WRITE, d, 8); + if (copy_to_user(d, &tll, 8)) + FPU_abort; + RE_ENTRANT_CHECK_ON; + + return 1; +} + +/* Put a long into user memory */ +int FPU_store_int32(FPU_REG *st0_ptr, u_char st0_tag, long __user *d) +{ + FPU_REG t; + int precision_loss; + + if (st0_tag == TAG_Empty) { + /* Empty register (stack underflow) */ + EXCEPTION(EX_StackUnder); + goto invalid_operand; + } else if (st0_tag == TAG_Special) { + st0_tag = FPU_Special(st0_ptr); + if ((st0_tag == TW_Infinity) || (st0_tag == TW_NaN)) { + EXCEPTION(EX_Invalid); + goto invalid_operand; + } + } + + reg_copy(st0_ptr, &t); + precision_loss = FPU_round_to_int(&t, st0_tag); + if (t.sigh || + ((t.sigl & 0x80000000) && + !((t.sigl == 0x80000000) && signnegative(&t)))) { + EXCEPTION(EX_Invalid); + /* This is a special case: see sec 16.2.5.1 of the 80486 book */ + invalid_operand: + if (control_word & EX_Invalid) { + /* Produce something like QNaN "indefinite" */ + t.sigl = 0x80000000; + } else + return 0; + } else { + if (precision_loss) + set_precision_flag(precision_loss); + if (signnegative(&t)) + t.sigl = -(long)t.sigl; + } + + RE_ENTRANT_CHECK_OFF; + FPU_access_ok(VERIFY_WRITE, d, 4); + FPU_put_user(t.sigl, (unsigned long __user *)d); + RE_ENTRANT_CHECK_ON; + + return 1; +} + +/* Put a short into user memory */ +int FPU_store_int16(FPU_REG *st0_ptr, u_char st0_tag, short __user *d) +{ + FPU_REG t; + int precision_loss; + + if (st0_tag == TAG_Empty) { + /* Empty register (stack underflow) */ + EXCEPTION(EX_StackUnder); + goto invalid_operand; + } else if (st0_tag == TAG_Special) { + st0_tag = FPU_Special(st0_ptr); + if ((st0_tag == TW_Infinity) || (st0_tag == TW_NaN)) { + EXCEPTION(EX_Invalid); + goto invalid_operand; + } + } + + reg_copy(st0_ptr, &t); + precision_loss = FPU_round_to_int(&t, st0_tag); + if (t.sigh || + ((t.sigl & 0xffff8000) && + !((t.sigl == 0x8000) && signnegative(&t)))) { + EXCEPTION(EX_Invalid); + /* This is a special case: see sec 16.2.5.1 of the 80486 book */ + invalid_operand: + if (control_word & EX_Invalid) { + /* Produce something like QNaN "indefinite" */ + t.sigl = 0x8000; + } else + return 0; + } else { + if (precision_loss) + set_precision_flag(precision_loss); + if (signnegative(&t)) + t.sigl = -t.sigl; + } + + RE_ENTRANT_CHECK_OFF; + FPU_access_ok(VERIFY_WRITE, d, 2); + FPU_put_user((short)t.sigl, d); + RE_ENTRANT_CHECK_ON; + + return 1; +} + +/* Put a packed bcd array into user memory */ +int FPU_store_bcd(FPU_REG *st0_ptr, u_char st0_tag, u_char __user *d) +{ + FPU_REG t; + unsigned long long ll; + u_char b; + int i, precision_loss; + u_char sign = (getsign(st0_ptr) == SIGN_NEG) ? 0x80 : 0; + + if (st0_tag == TAG_Empty) { + /* Empty register (stack underflow) */ + EXCEPTION(EX_StackUnder); + goto invalid_operand; + } else if (st0_tag == TAG_Special) { + st0_tag = FPU_Special(st0_ptr); + if ((st0_tag == TW_Infinity) || (st0_tag == TW_NaN)) { + EXCEPTION(EX_Invalid); + goto invalid_operand; + } + } + + reg_copy(st0_ptr, &t); + precision_loss = FPU_round_to_int(&t, st0_tag); + ll = significand(&t); + + /* Check for overflow, by comparing with 999999999999999999 decimal. */ + if ((t.sigh > 0x0de0b6b3) || + ((t.sigh == 0x0de0b6b3) && (t.sigl > 0xa763ffff))) { + EXCEPTION(EX_Invalid); + /* This is a special case: see sec 16.2.5.1 of the 80486 book */ + invalid_operand: + if (control_word & CW_Invalid) { + /* Produce the QNaN "indefinite" */ + RE_ENTRANT_CHECK_OFF; + FPU_access_ok(VERIFY_WRITE, d, 10); + for (i = 0; i < 7; i++) + FPU_put_user(0, d + i); /* These bytes "undefined" */ + FPU_put_user(0xc0, d + 7); /* This byte "undefined" */ + FPU_put_user(0xff, d + 8); + FPU_put_user(0xff, d + 9); + RE_ENTRANT_CHECK_ON; + return 1; + } else + return 0; + } else if (precision_loss) { + /* Precision loss doesn't stop the data transfer */ + set_precision_flag(precision_loss); + } + + RE_ENTRANT_CHECK_OFF; + FPU_access_ok(VERIFY_WRITE, d, 10); + RE_ENTRANT_CHECK_ON; + for (i = 0; i < 9; i++) { + b = FPU_div_small(&ll, 10); + b |= (FPU_div_small(&ll, 10)) << 4; + RE_ENTRANT_CHECK_OFF; + FPU_put_user(b, d + i); + RE_ENTRANT_CHECK_ON; + } + RE_ENTRANT_CHECK_OFF; + FPU_put_user(sign, d + 9); + RE_ENTRANT_CHECK_ON; + + return 1; +} + +/*===========================================================================*/ + +/* r gets mangled such that sig is int, sign: + it is NOT normalized */ +/* The return value (in eax) is zero if the result is exact, + if bits are changed due to rounding, truncation, etc, then + a non-zero value is returned */ +/* Overflow is signalled by a non-zero return value (in eax). + In the case of overflow, the returned significand always has the + largest possible value */ +int FPU_round_to_int(FPU_REG *r, u_char tag) +{ + u_char very_big; + unsigned eax; + + if (tag == TAG_Zero) { + /* Make sure that zero is returned */ + significand(r) = 0; + return 0; /* o.k. */ + } + + if (exponent(r) > 63) { + r->sigl = r->sigh = ~0; /* The largest representable number */ + return 1; /* overflow */ + } + + eax = FPU_shrxs(&r->sigl, 63 - exponent(r)); + very_big = !(~(r->sigh) | ~(r->sigl)); /* test for 0xfff...fff */ +#define half_or_more (eax & 0x80000000) +#define frac_part (eax) +#define more_than_half ((eax & 0x80000001) == 0x80000001) + switch (control_word & CW_RC) { + case RC_RND: + if (more_than_half /* nearest */ + || (half_or_more && (r->sigl & 1))) { /* odd -> even */ + if (very_big) + return 1; /* overflow */ + significand(r)++; + return PRECISION_LOST_UP; + } + break; + case RC_DOWN: + if (frac_part && getsign(r)) { + if (very_big) + return 1; /* overflow */ + significand(r)++; + return PRECISION_LOST_UP; + } + break; + case RC_UP: + if (frac_part && !getsign(r)) { + if (very_big) + return 1; /* overflow */ + significand(r)++; + return PRECISION_LOST_UP; + } + break; + case RC_CHOP: + break; + } + + return eax ? PRECISION_LOST_DOWN : 0; + +} + +/*===========================================================================*/ + +u_char __user *fldenv(fpu_addr_modes addr_modes, u_char __user *s) +{ + unsigned short tag_word = 0; + u_char tag; + int i; + + if ((addr_modes.default_mode == VM86) || + ((addr_modes.default_mode == PM16) + ^ (addr_modes.override.operand_size == OP_SIZE_PREFIX))) { + RE_ENTRANT_CHECK_OFF; + FPU_access_ok(VERIFY_READ, s, 0x0e); + FPU_get_user(control_word, (unsigned short __user *)s); + FPU_get_user(partial_status, (unsigned short __user *)(s + 2)); + FPU_get_user(tag_word, (unsigned short __user *)(s + 4)); + FPU_get_user(instruction_address.offset, + (unsigned short __user *)(s + 6)); + FPU_get_user(instruction_address.selector, + (unsigned short __user *)(s + 8)); + FPU_get_user(operand_address.offset, + (unsigned short __user *)(s + 0x0a)); + FPU_get_user(operand_address.selector, + (unsigned short __user *)(s + 0x0c)); + RE_ENTRANT_CHECK_ON; + s += 0x0e; + if (addr_modes.default_mode == VM86) { + instruction_address.offset + += (instruction_address.selector & 0xf000) << 4; + operand_address.offset += + (operand_address.selector & 0xf000) << 4; + } + } else { + RE_ENTRANT_CHECK_OFF; + FPU_access_ok(VERIFY_READ, s, 0x1c); + FPU_get_user(control_word, (unsigned short __user *)s); + FPU_get_user(partial_status, (unsigned short __user *)(s + 4)); + FPU_get_user(tag_word, (unsigned short __user *)(s + 8)); + FPU_get_user(instruction_address.offset, + (unsigned long __user *)(s + 0x0c)); + FPU_get_user(instruction_address.selector, + (unsigned short __user *)(s + 0x10)); + FPU_get_user(instruction_address.opcode, + (unsigned short __user *)(s + 0x12)); + FPU_get_user(operand_address.offset, + (unsigned long __user *)(s + 0x14)); + FPU_get_user(operand_address.selector, + (unsigned long __user *)(s + 0x18)); + RE_ENTRANT_CHECK_ON; + s += 0x1c; + } + +#ifdef PECULIAR_486 + control_word &= ~0xe080; +#endif /* PECULIAR_486 */ + + top = (partial_status >> SW_Top_Shift) & 7; + + if (partial_status & ~control_word & CW_Exceptions) + partial_status |= (SW_Summary | SW_Backward); + else + partial_status &= ~(SW_Summary | SW_Backward); + + for (i = 0; i < 8; i++) { + tag = tag_word & 3; + tag_word >>= 2; + + if (tag == TAG_Empty) + /* New tag is empty. Accept it */ + FPU_settag(i, TAG_Empty); + else if (FPU_gettag(i) == TAG_Empty) { + /* Old tag is empty and new tag is not empty. New tag is determined + by old reg contents */ + if (exponent(&fpu_register(i)) == -EXTENDED_Ebias) { + if (! + (fpu_register(i).sigl | fpu_register(i). + sigh)) + FPU_settag(i, TAG_Zero); + else + FPU_settag(i, TAG_Special); + } else if (exponent(&fpu_register(i)) == + 0x7fff - EXTENDED_Ebias) { + FPU_settag(i, TAG_Special); + } else if (fpu_register(i).sigh & 0x80000000) + FPU_settag(i, TAG_Valid); + else + FPU_settag(i, TAG_Special); /* An Un-normal */ + } + /* Else old tag is not empty and new tag is not empty. Old tag + remains correct */ + } + + return s; +} + +void frstor(fpu_addr_modes addr_modes, u_char __user *data_address) +{ + int i, regnr; + u_char __user *s = fldenv(addr_modes, data_address); + int offset = (top & 7) * 10, other = 80 - offset; + + /* Copy all registers in stack order. */ + RE_ENTRANT_CHECK_OFF; + FPU_access_ok(VERIFY_READ, s, 80); + __copy_from_user(register_base + offset, s, other); + if (offset) + __copy_from_user(register_base, s + other, offset); + RE_ENTRANT_CHECK_ON; + + for (i = 0; i < 8; i++) { + regnr = (i + top) & 7; + if (FPU_gettag(regnr) != TAG_Empty) + /* The loaded data over-rides all other cases. */ + FPU_settag(regnr, FPU_tagof(&st(i))); + } + +} + +u_char __user *fstenv(fpu_addr_modes addr_modes, u_char __user *d) +{ + if ((addr_modes.default_mode == VM86) || + ((addr_modes.default_mode == PM16) + ^ (addr_modes.override.operand_size == OP_SIZE_PREFIX))) { + RE_ENTRANT_CHECK_OFF; + FPU_access_ok(VERIFY_WRITE, d, 14); +#ifdef PECULIAR_486 + FPU_put_user(control_word & ~0xe080, (unsigned long __user *)d); +#else + FPU_put_user(control_word, (unsigned short __user *)d); +#endif /* PECULIAR_486 */ + FPU_put_user(status_word(), (unsigned short __user *)(d + 2)); + FPU_put_user(fpu_tag_word, (unsigned short __user *)(d + 4)); + FPU_put_user(instruction_address.offset, + (unsigned short __user *)(d + 6)); + FPU_put_user(operand_address.offset, + (unsigned short __user *)(d + 0x0a)); + if (addr_modes.default_mode == VM86) { + FPU_put_user((instruction_address. + offset & 0xf0000) >> 4, + (unsigned short __user *)(d + 8)); + FPU_put_user((operand_address.offset & 0xf0000) >> 4, + (unsigned short __user *)(d + 0x0c)); + } else { + FPU_put_user(instruction_address.selector, + (unsigned short __user *)(d + 8)); + FPU_put_user(operand_address.selector, + (unsigned short __user *)(d + 0x0c)); + } + RE_ENTRANT_CHECK_ON; + d += 0x0e; + } else { + RE_ENTRANT_CHECK_OFF; + FPU_access_ok(VERIFY_WRITE, d, 7 * 4); +#ifdef PECULIAR_486 + control_word &= ~0xe080; + /* An 80486 sets nearly all of the reserved bits to 1. */ + control_word |= 0xffff0040; + partial_status = status_word() | 0xffff0000; + fpu_tag_word |= 0xffff0000; + I387->soft.fcs &= ~0xf8000000; + I387->soft.fos |= 0xffff0000; +#endif /* PECULIAR_486 */ + if (__copy_to_user(d, &control_word, 7 * 4)) + FPU_abort; + RE_ENTRANT_CHECK_ON; + d += 0x1c; + } + + control_word |= CW_Exceptions; + partial_status &= ~(SW_Summary | SW_Backward); + + return d; +} + +void fsave(fpu_addr_modes addr_modes, u_char __user *data_address) +{ + u_char __user *d; + int offset = (top & 7) * 10, other = 80 - offset; + + d = fstenv(addr_modes, data_address); + + RE_ENTRANT_CHECK_OFF; + FPU_access_ok(VERIFY_WRITE, d, 80); + + /* Copy all registers in stack order. */ + if (__copy_to_user(d, register_base + offset, other)) + FPU_abort; + if (offset) + if (__copy_to_user(d + other, register_base, offset)) + FPU_abort; + RE_ENTRANT_CHECK_ON; + + finit(); +} + +/*===========================================================================*/ |