Bochs/bochs/fpu/ferr.cc
Stanislav Shwartsman 04124133c0 freeze softfloat-fpu-ver3 branhc and open it for free testing
I will continue the development in new softfloat-fpu-ver4 branch
Current version already implements ALL FPU instructions except
   FSIN, FCOS, FSINCOS, FPTAN, FPATAN, FYL2XP1, F2XM1, FYL2X
I think it solved all currently reported bugs and feature requests
related to FPU code.
Please write your own test programms and test the implemntation in all ways you can.
Thanks,
Stanislav
2004-04-09 12:29:50 +00:00

87 lines
2.7 KiB
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Executable File

/////////////////////////////////////////////////////////////////////////
// Copyright (C) 2004 MandrakeSoft S.A.
//
// MandrakeSoft S.A.
// 43, rue d'Aboukir
// 75002 Paris - France
// http://www.linux-mandrake.com/
// http://www.mandrakesoft.com/
//
// 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
/////////////////////////////////////////////////////////////////////////
#define NEED_CPU_REG_SHORTCUTS 1
#include "bochs.h"
#define LOG_THIS BX_CPU_THIS_PTR
#if BX_SUPPORT_FPU
#include "softfloat-specialize.h"
void BX_CPU_C::FPU_stack_overflow(void)
{
/* The masked response */
if (BX_CPU_THIS_PTR the_i387.is_IA_masked())
{
BX_CPU_THIS_PTR the_i387.FPU_push();
BX_WRITE_FPU_REGISTER_AND_TAG(floatx80_default_nan, FPU_Tag_Special, 0);
}
BX_CPU_THIS_PTR FPU_exception(FPU_EX_Stack_Overflow);
}
void BX_CPU_C::FPU_stack_underflow(int stnr, int pop_stack)
{
/* The masked response */
if (BX_CPU_THIS_PTR the_i387.is_IA_masked())
{
BX_WRITE_FPU_REGISTER_AND_TAG(floatx80_default_nan, FPU_Tag_Special, stnr);
if (pop_stack)
BX_CPU_THIS_PTR the_i387.FPU_pop();
}
BX_CPU_THIS_PTR FPU_exception(FPU_EX_Stack_Underflow);
}
/* Returns 1 if unmasked exception occured */
int BX_CPU_C::FPU_exception(int exception)
{
int unmasked = 0;
/* Extract only the bits which we use to set the status word */
exception &= (FPU_SW_Exceptions_Mask);
/* Set the corresponding exception bits */
FPU_PARTIAL_STATUS |= exception;
/* Set summary bits iff exception isn't masked */
if (FPU_PARTIAL_STATUS & ~FPU_CONTROL_WORD & FPU_CW_Exceptions_Mask)
{
FPU_PARTIAL_STATUS |= (FPU_SW_Summary | FPU_SW_Backward);
unmasked = 1;
}
if (exception & (FPU_SW_Stack_Fault | FPU_EX_Precision))
{
if (! (exception & FPU_SW_C1))
/* This bit distinguishes over- from underflow for a stack fault,
and roundup from round-down for precision loss. */
FPU_PARTIAL_STATUS &= ~FPU_SW_C1;
}
return unmasked;
}
#endif