get_fpc_csr(3) [ultrix man page]

fpc(3)							     Library Functions Manual							    fpc(3)

Name
       fpc, get_fpc_csr, set_fpc_csr, swapRM, swapINX - floating-point control registers

Syntax
       #include <mips/fpu.h>

       int get_fpc_csr()

       int set_fpc_csr(csr)
       int csr;

       int get_fpc_irr()

       int swapRM(x)
       int x;

       int swapINX(x)
       int x;

Description
       These  functions  are  to  get  and set the floating-point control registers of RISC floating-point units.  All of these functions take and
       return their values as 32 bit integers.

       The file <mips/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.

       RISC  floating-point  implementations  have  a control and status register and an implementation revision register.  The control and status
       register is returned by The routine sets the control and status register and returns the old value.  The implementation	revision  register
       is read-only and is returned by the routine

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

								       RISC								    fpc(3)

UNW_GET_FPREG(3)					       Programming Library						  UNW_GET_FPREG(3)

NAME

       unw_get_fpreg -- get contents of floating-point register

SYNOPSIS

       #include <libunwind.h>

       int unw_get_fpreg(unw_cursor_t *cp, unw_regnum_t reg, unw_fpreg_t *valp);

DESCRIPTION

       The  unw_get_fpreg() routine reads the value of floating-point register reg in the stack frame identified by cursor cp and stores the value
       in the variable pointed to by valp.

       The register numbering is target-dependent and described in separate manual pages (e.g., libunwind-ia64(3) for the IA-64 target).  Further-
       more,  the exact set of accessible registers may depend on the type of frame that cp is referring to. For ordinary stack frames, it is nor-
       mally possible to access only the preserved (``callee-saved'') registers and frame-related registers (such as the stack-pointer).  However,
       for signal frames (see unw_is_signal_frame(3)), it is usually possible to access all registers.

       Note  that  unw_get_fpreg()  can only read the contents of floating-point registers. See unw_get_fpreg(3) for a way to read registers which
       fit in a single word.

RETURN VALUE

       On successful completion, unw_get_fpreg() returns 0.  Otherwise the negative value of one of the error-codes below is returned.

THREAD AND SIGNAL SAFETY

       unw_get_fpreg() is thread-safe as well as safe to use from a signal handler.

ERRORS

       UNW_EUNSPEC
	       An unspecified error occurred.

       UNW_EBADREG
	       An attempt was made to read a register that is either invalid or not accessible in the current frame.

       In addition, unw_get_fpreg() may return any error returned by the access_mem(), access_reg(), and access_fpreg() call-backs  (see  unw_cre-
       ate_addr_space(3)).

SEE ALSO

       libunwind(3), libunwind-ia64(3), unw_get_reg(3), unw_is_fpreg(3), unw_is_signal_frame(3), unw_set_fpreg(3)

AUTHOR

       David Mosberger-Tang
       Email: dmosberger@gmail.com
       WWW: http://www.nongnu.org/libunwind/.

Programming Library						  16 August 2007						  UNW_GET_FPREG(3)