Bochs/bochs/cpu/fpu/fpu_load_store.cc
2017-05-05 20:56:13 +00:00

779 lines
18 KiB
C++

/////////////////////////////////////////////////////////////////////////
// $Id$
/////////////////////////////////////////////////////////////////////////
//
// Copyright (c) 2003-2015 Stanislav Shwartsman
// Written by Stanislav Shwartsman [sshwarts at sourceforge net]
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; either
// version 2 of the License, or (at your option) any later version.
//
// This library 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
// Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
//
/////////////////////////////////////////////////////////////////////////
#define NEED_CPU_REG_SHORTCUTS 1
#include "bochs.h"
#include "cpu/cpu.h"
#define LOG_THIS BX_CPU_THIS_PTR
#if BX_SUPPORT_FPU
#define swap_values16u(a, b) { Bit16u tmp = a; a = b; b = tmp; }
extern float_status_t i387cw_to_softfloat_status_word(Bit16u control_word);
#include "softfloatx80.h"
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::FLD_STi(bxInstruction_c *i)
{
BX_CPU_THIS_PTR prepareFPU(i);
FPU_update_last_instruction(i);
clear_C1();
if (! IS_TAG_EMPTY(-1))
{
FPU_stack_overflow(i);
BX_NEXT_INSTR(i);
}
floatx80 sti_reg = floatx80_default_nan;
if (IS_TAG_EMPTY(i->src()))
{
FPU_exception(i, FPU_EX_Stack_Underflow);
if (! BX_CPU_THIS_PTR the_i387.is_IA_masked())
BX_NEXT_INSTR(i);
}
else {
sti_reg = BX_READ_FPU_REG(i->src());
}
BX_CPU_THIS_PTR the_i387.FPU_push();
BX_WRITE_FPU_REG(sti_reg, 0);
BX_NEXT_INSTR(i);
}
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::FLD_SINGLE_REAL(bxInstruction_c *i)
{
BX_CPU_THIS_PTR prepareFPU(i);
RMAddr(i) = BX_CPU_RESOLVE_ADDR(i);
float32 load_reg = read_virtual_dword(i->seg(), RMAddr(i));
FPU_update_last_instruction(i);
clear_C1();
if (! IS_TAG_EMPTY(-1)) {
FPU_stack_overflow(i);
BX_NEXT_INSTR(i);
}
float_status_t status =
i387cw_to_softfloat_status_word(BX_CPU_THIS_PTR the_i387.get_control_word());
// convert to floatx80 format
floatx80 result = float32_to_floatx80(load_reg, status);
unsigned unmasked = FPU_exception(i, status.float_exception_flags);
if (! (unmasked & FPU_CW_Invalid)) {
BX_CPU_THIS_PTR the_i387.FPU_push();
BX_WRITE_FPU_REG(result, 0);
}
BX_NEXT_INSTR(i);
}
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::FLD_DOUBLE_REAL(bxInstruction_c *i)
{
BX_CPU_THIS_PTR prepareFPU(i);
RMAddr(i) = BX_CPU_RESOLVE_ADDR(i);
float64 load_reg = read_virtual_qword(i->seg(), RMAddr(i));
FPU_update_last_instruction(i);
clear_C1();
if (! IS_TAG_EMPTY(-1)) {
FPU_stack_overflow(i);
BX_NEXT_INSTR(i);
}
float_status_t status =
i387cw_to_softfloat_status_word(BX_CPU_THIS_PTR the_i387.get_control_word());
// convert to floatx80 format
floatx80 result = float64_to_floatx80(load_reg, status);
unsigned unmasked = FPU_exception(i, status.float_exception_flags);
if (! (unmasked & FPU_CW_Invalid)) {
BX_CPU_THIS_PTR the_i387.FPU_push();
BX_WRITE_FPU_REG(result, 0);
}
BX_NEXT_INSTR(i);
}
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::FLD_EXTENDED_REAL(bxInstruction_c *i)
{
BX_CPU_THIS_PTR prepareFPU(i);
floatx80 result;
RMAddr(i) = BX_CPU_RESOLVE_ADDR(i);
result.fraction = read_virtual_qword(i->seg(), RMAddr(i));
result.exp = read_virtual_word(i->seg(), (RMAddr(i)+8) & i->asize_mask());
FPU_update_last_instruction(i);
clear_C1();
if (! IS_TAG_EMPTY(-1)) {
FPU_stack_overflow(i);
}
else {
BX_CPU_THIS_PTR the_i387.FPU_push();
BX_WRITE_FPU_REG(result, 0);
}
BX_NEXT_INSTR(i);
}
/* DF /0 */
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::FILD_WORD_INTEGER(bxInstruction_c *i)
{
BX_CPU_THIS_PTR prepareFPU(i);
RMAddr(i) = BX_CPU_RESOLVE_ADDR(i);
Bit16s load_reg = (Bit16s) read_virtual_word(i->seg(), RMAddr(i));
FPU_update_last_instruction(i);
clear_C1();
if (! IS_TAG_EMPTY(-1)) {
FPU_stack_overflow(i);
}
else {
floatx80 result = int32_to_floatx80((Bit32s) load_reg);
BX_CPU_THIS_PTR the_i387.FPU_push();
BX_WRITE_FPU_REG(result, 0);
}
BX_NEXT_INSTR(i);
}
/* DB /0 */
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::FILD_DWORD_INTEGER(bxInstruction_c *i)
{
BX_CPU_THIS_PTR prepareFPU(i);
RMAddr(i) = BX_CPU_RESOLVE_ADDR(i);
Bit32s load_reg = (Bit32s) read_virtual_dword(i->seg(), RMAddr(i));
FPU_update_last_instruction(i);
clear_C1();
if (! IS_TAG_EMPTY(-1)) {
FPU_stack_overflow(i);
}
else {
floatx80 result = int32_to_floatx80(load_reg);
BX_CPU_THIS_PTR the_i387.FPU_push();
BX_WRITE_FPU_REG(result, 0);
}
BX_NEXT_INSTR(i);
}
/* DF /5 */
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::FILD_QWORD_INTEGER(bxInstruction_c *i)
{
BX_CPU_THIS_PTR prepareFPU(i);
RMAddr(i) = BX_CPU_RESOLVE_ADDR(i);
Bit64s load_reg = (Bit64s) read_virtual_qword(i->seg(), RMAddr(i));
FPU_update_last_instruction(i);
clear_C1();
if (! IS_TAG_EMPTY(-1)) {
FPU_stack_overflow(i);
}
else {
floatx80 result = int64_to_floatx80(load_reg);
BX_CPU_THIS_PTR the_i387.FPU_push();
BX_WRITE_FPU_REG(result, 0);
}
BX_NEXT_INSTR(i);
}
/* DF /4 */
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::FBLD_PACKED_BCD(bxInstruction_c *i)
{
BX_CPU_THIS_PTR prepareFPU(i);
RMAddr(i) = BX_CPU_RESOLVE_ADDR(i);
Bit16u hi2 = read_virtual_word(i->seg(), (RMAddr(i) + 8) & i->asize_mask());
Bit64u lo8 = read_virtual_qword(i->seg(), RMAddr(i));
FPU_update_last_instruction(i);
clear_C1();
if (! IS_TAG_EMPTY(-1))
{
FPU_stack_overflow(i);
BX_NEXT_INSTR(i);
}
// convert packed BCD to 64-bit integer
Bit64s scale = 1;
Bit64s val64 = 0;
for (int n = 0; n < 16; n++)
{
val64 += (lo8 & 0x0f) * scale;
lo8 >>= 4;
scale *= 10;
}
val64 += (hi2 & 0x0f) * scale;
val64 += ((hi2>>4) & 0x0f) * scale * 10;
floatx80 result = int64_to_floatx80(val64);
if (hi2 & 0x8000) // set negative
floatx80_chs(result);
BX_CPU_THIS_PTR the_i387.FPU_push();
BX_WRITE_FPU_REG(result, 0);
BX_NEXT_INSTR(i);
}
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::FST_STi(bxInstruction_c *i)
{
BX_CPU_THIS_PTR prepareFPU(i);
FPU_update_last_instruction(i);
int pop_stack = 0;
if (i->getIaOpcode() == BX_IA_FSTP_STi)
pop_stack = 1;
clear_C1();
if (IS_TAG_EMPTY(0)) {
FPU_stack_underflow(i, i->dst(), pop_stack);
}
else {
floatx80 st0_reg = BX_READ_FPU_REG(0);
BX_WRITE_FPU_REG(st0_reg, i->dst());
if (pop_stack)
BX_CPU_THIS_PTR the_i387.FPU_pop();
}
BX_NEXT_INSTR(i);
}
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::FST_SINGLE_REAL(bxInstruction_c *i)
{
BX_CPU_THIS_PTR prepareFPU(i);
RMAddr(i) = BX_CPU_RESOLVE_ADDR(i);
FPU_update_last_instruction(i);
Bit16u x87_sw = FPU_PARTIAL_STATUS;
clear_C1();
float32 save_reg = float32_default_nan; /* The masked response */
int pop_stack = 0;
if (i->getIaOpcode() == BX_IA_FSTP_SINGLE_REAL)
pop_stack = 1;
if (IS_TAG_EMPTY(0))
{
FPU_exception(i, FPU_EX_Stack_Underflow);
if (! BX_CPU_THIS_PTR the_i387.is_IA_masked())
BX_NEXT_INSTR(i);
}
else
{
float_status_t status =
i387cw_to_softfloat_status_word(BX_CPU_THIS_PTR the_i387.get_control_word());
save_reg = floatx80_to_float32(BX_READ_FPU_REG(0), status);
if (FPU_exception(i, status.float_exception_flags, 1))
BX_NEXT_INSTR(i);
}
// store to the memory might generate an exception, in this case origial FPU_SW must be kept
swap_values16u(x87_sw, FPU_PARTIAL_STATUS);
write_virtual_dword(i->seg(), RMAddr(i), save_reg);
FPU_PARTIAL_STATUS = x87_sw;
if (pop_stack)
BX_CPU_THIS_PTR the_i387.FPU_pop();
BX_NEXT_INSTR(i);
}
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::FST_DOUBLE_REAL(bxInstruction_c *i)
{
BX_CPU_THIS_PTR prepareFPU(i);
RMAddr(i) = BX_CPU_RESOLVE_ADDR(i);
FPU_update_last_instruction(i);
Bit16u x87_sw = FPU_PARTIAL_STATUS;
clear_C1();
float64 save_reg = float64_default_nan; /* The masked response */
int pop_stack = 0;
if (i->getIaOpcode() == BX_IA_FSTP_DOUBLE_REAL)
pop_stack = 1;
if (IS_TAG_EMPTY(0))
{
FPU_exception(i, FPU_EX_Stack_Underflow);
if (! BX_CPU_THIS_PTR the_i387.is_IA_masked())
BX_NEXT_INSTR(i);
}
else
{
float_status_t status =
i387cw_to_softfloat_status_word(BX_CPU_THIS_PTR the_i387.get_control_word());
save_reg = floatx80_to_float64(BX_READ_FPU_REG(0), status);
if (FPU_exception(i, status.float_exception_flags, 1))
BX_NEXT_INSTR(i);
}
// store to the memory might generate an exception, in this case origial FPU_SW must be kept
swap_values16u(x87_sw, FPU_PARTIAL_STATUS);
write_virtual_qword(i->seg(), RMAddr(i), save_reg);
FPU_PARTIAL_STATUS = x87_sw;
if (pop_stack)
BX_CPU_THIS_PTR the_i387.FPU_pop();
BX_NEXT_INSTR(i);
}
/* DB /7 */
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::FSTP_EXTENDED_REAL(bxInstruction_c *i)
{
BX_CPU_THIS_PTR prepareFPU(i);
RMAddr(i) = BX_CPU_RESOLVE_ADDR(i);
FPU_update_last_instruction(i);
clear_C1();
floatx80 save_reg = floatx80_default_nan; /* The masked response */
if (IS_TAG_EMPTY(0))
{
FPU_exception(i, FPU_EX_Stack_Underflow);
if (! BX_CPU_THIS_PTR the_i387.is_IA_masked())
BX_NEXT_INSTR(i);
}
else
{
save_reg = BX_READ_FPU_REG(0);
}
write_virtual_qword(i->seg(), RMAddr(i), save_reg.fraction);
write_virtual_word(i->seg(), (RMAddr(i) + 8) & i->asize_mask(), save_reg.exp);
BX_CPU_THIS_PTR the_i387.FPU_pop();
BX_NEXT_INSTR(i);
}
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::FIST_WORD_INTEGER(bxInstruction_c *i)
{
BX_CPU_THIS_PTR prepareFPU(i);
RMAddr(i) = BX_CPU_RESOLVE_ADDR(i);
FPU_update_last_instruction(i);
Bit16u x87_sw = FPU_PARTIAL_STATUS;
Bit16s save_reg = int16_indefinite;
int pop_stack = 0;
if (i->getIaOpcode() == BX_IA_FISTP_WORD_INTEGER)
pop_stack = 1;
clear_C1();
if (IS_TAG_EMPTY(0))
{
FPU_exception(i, FPU_EX_Stack_Underflow);
if (! BX_CPU_THIS_PTR the_i387.is_IA_masked())
BX_NEXT_INSTR(i);
}
else
{
float_status_t status =
i387cw_to_softfloat_status_word(BX_CPU_THIS_PTR the_i387.get_control_word());
save_reg = floatx80_to_int16(BX_READ_FPU_REG(0), status);
if (FPU_exception(i, status.float_exception_flags, 1))
BX_NEXT_INSTR(i);
}
// store to the memory might generate an exception, in this case origial FPU_SW must be kept
swap_values16u(x87_sw, FPU_PARTIAL_STATUS);
write_virtual_word(i->seg(), RMAddr(i), (Bit16u)(save_reg));
FPU_PARTIAL_STATUS = x87_sw;
if (pop_stack)
BX_CPU_THIS_PTR the_i387.FPU_pop();
BX_NEXT_INSTR(i);
}
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::FIST_DWORD_INTEGER(bxInstruction_c *i)
{
BX_CPU_THIS_PTR prepareFPU(i);
RMAddr(i) = BX_CPU_RESOLVE_ADDR(i);
FPU_update_last_instruction(i);
Bit16u x87_sw = FPU_PARTIAL_STATUS;
Bit32s save_reg = int32_indefinite; /* The masked response */
int pop_stack = 0;
if (i->getIaOpcode() == BX_IA_FISTP_DWORD_INTEGER)
pop_stack = 1;
clear_C1();
if (IS_TAG_EMPTY(0))
{
FPU_exception(i, FPU_EX_Stack_Underflow);
if (! BX_CPU_THIS_PTR the_i387.is_IA_masked())
BX_NEXT_INSTR(i);
}
else
{
float_status_t status =
i387cw_to_softfloat_status_word(BX_CPU_THIS_PTR the_i387.get_control_word());
save_reg = floatx80_to_int32(BX_READ_FPU_REG(0), status);
if (FPU_exception(i, status.float_exception_flags, 1))
BX_NEXT_INSTR(i);
}
// store to the memory might generate an exception, in this case origial FPU_SW must be kept
swap_values16u(x87_sw, FPU_PARTIAL_STATUS);
write_virtual_dword(i->seg(), RMAddr(i), (Bit32u)(save_reg));
FPU_PARTIAL_STATUS = x87_sw;
if (pop_stack)
BX_CPU_THIS_PTR the_i387.FPU_pop();
BX_NEXT_INSTR(i);
}
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::FISTP_QWORD_INTEGER(bxInstruction_c *i)
{
BX_CPU_THIS_PTR prepareFPU(i);
RMAddr(i) = BX_CPU_RESOLVE_ADDR(i);
FPU_update_last_instruction(i);
Bit16u x87_sw = FPU_PARTIAL_STATUS;
Bit64s save_reg = int64_indefinite; /* The masked response */
clear_C1();
if (IS_TAG_EMPTY(0))
{
FPU_exception(i, FPU_EX_Stack_Underflow);
if (! BX_CPU_THIS_PTR the_i387.is_IA_masked())
BX_NEXT_INSTR(i);
}
else
{
float_status_t status =
i387cw_to_softfloat_status_word(BX_CPU_THIS_PTR the_i387.get_control_word());
save_reg = floatx80_to_int64(BX_READ_FPU_REG(0), status);
if (FPU_exception(i, status.float_exception_flags, 1))
BX_NEXT_INSTR(i);
}
// store to the memory might generate an exception, in this case origial FPU_SW must be kept
swap_values16u(x87_sw, FPU_PARTIAL_STATUS);
write_virtual_qword(i->seg(), RMAddr(i), (Bit64u)(save_reg));
FPU_PARTIAL_STATUS = x87_sw;
BX_CPU_THIS_PTR the_i387.FPU_pop();
BX_NEXT_INSTR(i);
}
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::FBSTP_PACKED_BCD(bxInstruction_c *i)
{
BX_CPU_THIS_PTR prepareFPU(i);
RMAddr(i) = BX_CPU_RESOLVE_ADDR(i);
FPU_update_last_instruction(i);
Bit16u x87_sw = FPU_PARTIAL_STATUS;
/*
* The packed BCD integer indefinite encoding (FFFFC000000000000000H)
* is stored in response to a masked floating-point invalid-operation
* exception.
*/
Bit16u save_reg_hi = 0xFFFF;
Bit64u save_reg_lo = BX_CONST64(0xC000000000000000);
clear_C1();
if (IS_TAG_EMPTY(0))
{
FPU_exception(i, FPU_EX_Stack_Underflow);
if (! BX_CPU_THIS_PTR the_i387.is_IA_masked())
BX_NEXT_INSTR(i);
}
else
{
float_status_t status =
i387cw_to_softfloat_status_word(BX_CPU_THIS_PTR the_i387.get_control_word());
floatx80 reg = BX_READ_FPU_REG(0);
Bit64s save_val = floatx80_to_int64(reg, status);
int sign = (reg.exp & 0x8000) != 0;
if (sign)
save_val = -save_val;
if (save_val > BX_CONST64(999999999999999999)) {
status.float_exception_flags = float_flag_invalid; // throw away other flags
}
if (! (status.float_exception_flags & float_flag_invalid))
{
save_reg_hi = (sign) ? 0x8000 : 0;
save_reg_lo = 0;
for (int i=0; i<16; i++) {
save_reg_lo += ((Bit64u)(save_val % 10)) << (4*i);
save_val /= 10;
}
save_reg_hi += (Bit16u)(save_val % 10);
save_val /= 10;
save_reg_hi += (Bit16u)(save_val % 10) << 4;
}
/* check for fpu arithmetic exceptions */
if (FPU_exception(i, status.float_exception_flags, 1))
BX_NEXT_INSTR(i);
}
// store to the memory might generate an exception, in this case origial FPU_SW must be kept
swap_values16u(x87_sw, FPU_PARTIAL_STATUS);
// write packed bcd to memory
write_virtual_qword(i->seg(), RMAddr(i), save_reg_lo);
write_virtual_word(i->seg(), (RMAddr(i) + 8) & i->asize_mask(), save_reg_hi);
FPU_PARTIAL_STATUS = x87_sw;
BX_CPU_THIS_PTR the_i387.FPU_pop();
BX_NEXT_INSTR(i);
}
/* DF /1 */
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::FISTTP16(bxInstruction_c *i)
{
BX_CPU_THIS_PTR prepareFPU(i);
RMAddr(i) = BX_CPU_RESOLVE_ADDR(i);
FPU_update_last_instruction(i);
Bit16u x87_sw = FPU_PARTIAL_STATUS;
Bit16s save_reg = int16_indefinite; /* The masked response */
clear_C1();
if (IS_TAG_EMPTY(0))
{
FPU_exception(i, FPU_EX_Stack_Underflow);
if (! BX_CPU_THIS_PTR the_i387.is_IA_masked())
BX_NEXT_INSTR(i);
}
else
{
float_status_t status =
i387cw_to_softfloat_status_word(BX_CPU_THIS_PTR the_i387.get_control_word());
save_reg = floatx80_to_int16_round_to_zero(BX_READ_FPU_REG(0), status);
if (FPU_exception(i, status.float_exception_flags, 1))
BX_NEXT_INSTR(i);
}
// store to the memory might generate an exception, in this case origial FPU_SW must be kept
swap_values16u(x87_sw, FPU_PARTIAL_STATUS);
write_virtual_word(i->seg(), RMAddr(i), (Bit16u)(save_reg));
FPU_PARTIAL_STATUS = x87_sw;
BX_CPU_THIS_PTR the_i387.FPU_pop();
BX_NEXT_INSTR(i);
}
/* DB /1 */
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::FISTTP32(bxInstruction_c *i)
{
BX_CPU_THIS_PTR prepareFPU(i);
RMAddr(i) = BX_CPU_RESOLVE_ADDR(i);
FPU_update_last_instruction(i);
Bit16u x87_sw = FPU_PARTIAL_STATUS;
Bit32s save_reg = int32_indefinite; /* The masked response */
clear_C1();
if (IS_TAG_EMPTY(0))
{
FPU_exception(i, FPU_EX_Stack_Underflow);
if (! BX_CPU_THIS_PTR the_i387.is_IA_masked())
BX_NEXT_INSTR(i);
}
else
{
float_status_t status =
i387cw_to_softfloat_status_word(BX_CPU_THIS_PTR the_i387.get_control_word());
save_reg = floatx80_to_int32_round_to_zero(BX_READ_FPU_REG(0), status);
if (FPU_exception(i, status.float_exception_flags, 1))
BX_NEXT_INSTR(i);
}
// store to the memory might generate an exception, in this case origial FPU_SW must be kept
swap_values16u(x87_sw, FPU_PARTIAL_STATUS);
write_virtual_dword(i->seg(), RMAddr(i), (Bit32u)(save_reg));
FPU_PARTIAL_STATUS = x87_sw;
BX_CPU_THIS_PTR the_i387.FPU_pop();
BX_NEXT_INSTR(i);
}
/* DD /1 */
BX_INSF_TYPE BX_CPP_AttrRegparmN(1) BX_CPU_C::FISTTP64(bxInstruction_c *i)
{
BX_CPU_THIS_PTR prepareFPU(i);
RMAddr(i) = BX_CPU_RESOLVE_ADDR(i);
FPU_update_last_instruction(i);
Bit16u x87_sw = FPU_PARTIAL_STATUS;
Bit64s save_reg = int64_indefinite; /* The masked response */
clear_C1();
if (IS_TAG_EMPTY(0))
{
FPU_exception(i, FPU_EX_Stack_Underflow);
if (! BX_CPU_THIS_PTR the_i387.is_IA_masked())
BX_NEXT_INSTR(i);
}
else
{
float_status_t status =
i387cw_to_softfloat_status_word(BX_CPU_THIS_PTR the_i387.get_control_word());
save_reg = floatx80_to_int64_round_to_zero(BX_READ_FPU_REG(0), status);
if (FPU_exception(i, status.float_exception_flags, 1))
BX_NEXT_INSTR(i);
}
// store to the memory might generate an exception, in this case origial FPU_SW must be kept
swap_values16u(x87_sw, FPU_PARTIAL_STATUS);
write_virtual_qword(i->seg(), RMAddr(i), (Bit64u)(save_reg));
FPU_PARTIAL_STATUS = x87_sw;
BX_CPU_THIS_PTR the_i387.FPU_pop();
BX_NEXT_INSTR(i);
}
#endif