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FPC(3C)                                                                FPC(3C)



NAME
     fpc: get_fpc_csr, set_fpc_csr, get_fpc_irr, swapRM, swapINX - floating-
     point control registers

SYNOPSIS
     #include <sys/fpu.h>

     int getfpccsr(void);

     int setfpccsr(int csr);

     int getfpcirr(void);

     int swapRM(int x);

     int swapINX(int x);

DESCRIPTION
     These routines are to get and set the floating-point control registers of
     MIPS floating-point units.  All of these routines take and or return
     their values as 32 bit integers.

     The file <sys/fpu.h> contains unions for each of the control registers.
     Each union contains a structure that breaks out the bit fields into the
     logical parts for each control register.  This file also contains
     constants for fields of the control registers.

     All implementations of MIPS floating-point have a control and status
     register and a implementation revision register.  The control and status
     register is returned by get_fpc_csr. The routine set_fpc_csr sets the
     control and status register and returns the old value.  The
     implementation revision register is read-only and is returned by the
     routine get_fpc_irr.

     The routine swapRM sets only the rounding mode and returns the old
     rounding mode.  The routine swapINX sets only the sticky inexact bit and
     returns the old one.  The bits in the arguments and return values to
     swapRM and swapINX are right justified.

NOTES
     swapRM and swapINX are in libm.a . The link editor searches this library
     under the "-lm" option.

ALSO SEE
     R4000 Microprocessor User's Manual










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