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#include <fpu_control.h>
#include <asm/fpu.h>
extern void __ieee_set_fp_control (unsigned long);
extern unsigned long __ieee_get_fp_control (void);
static inline unsigned long
rdfpcr (void)
{
unsigned long fpcr;
asm ("trapb; mf_fpcr $f0; trapb; stt $f0,%0" : "m="(fpcr));
return fpcr;
}
static inline void
wrfpcr (unsigned long fpcr)
{
asm volatile ("ldt $f0,%0; trapb; mt_fpcr $f0; trapb" :: "m"(fpcr));
}
void
__setfpucw (unsigned short fpu_control)
{
unsigned long fpcr = 0, fpcw = 0;
if (!fpu_control)
fpu_control = _FPU_DEFAULT;
/* first, set dynamic rounding mode: */
fpcr = rdfpcr();
fpcr &= ~FPCR_DYN_MASK;
switch (fpu_control & 0xc00) {
case _FPU_RC_NEAREST: fpcr |= FPCR_DYN_NORMAL; break;
case _FPU_RC_DOWN: fpcr |= FPCR_DYN_MINUS; break;
case _FPU_RC_UP: fpcr |= FPCR_DYN_PLUS; break;
case _FPU_RC_ZERO: fpcr |= FPCR_DYN_CHOPPED; break;
}
wrfpcr(fpcr);
/* now tell kernel about traps that we like to hear about: */
fpcw = __ieee_get_fp_control();
fpcw &= ~IEEE_TRAP_ENABLE_MASK;
if (!(fpu_control & _FPU_MASK_IM))
fpcw |= IEEE_TRAP_ENABLE_INV;
if (!(fpu_control & _FPU_MASK_DM))
fpcw |= IEEE_TRAP_ENABLE_UNF;
if (!(fpu_control & _FPU_MASK_ZM))
fpcw |= IEEE_TRAP_ENABLE_DZE;
if (!(fpu_control & _FPU_MASK_OM))
fpcw |= IEEE_TRAP_ENABLE_OVF;
if (!(fpu_control & _FPU_MASK_PM))
fpcw |= IEEE_TRAP_ENABLE_INE;
__ieee_set_fp_control(fpcw);
__fpu_control = fpu_control; /* update global copy */
}
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