2fe8fb192f
There is important information about booting non-ack images in docs/UPDATING. ack/aout-format images can't be built any more, and booting clang/ELF-format ones is a little different. Updating to the new boot monitor is recommended. Changes in this commit: . drop boot monitor -> allowing dropping ack support . facility to copy ELF boot files to /boot so that old boot monitor can still boot fairly easily, see UPDATING . no more ack-format libraries -> single-case libraries . some cleanup of OBJECT_FMT, COMPILER_TYPE, etc cases . drop several ack toolchain commands, but not all support commands (e.g. aal is gone but acksize is not yet). . a few libc files moved to netbsd libc dir . new /bin/date as minix date used code in libc/ . test compile fix . harmonize includes . /usr/lib is no longer special: without ack, /usr/lib plays no kind of special bootstrapping role any more and bootstrapping is done exclusively through packages, so releases depend even less on the state of the machine making them now. . rename nbsd_lib* to lib* . reduce mtree
141 lines
3.8 KiB
Groff
141 lines
3.8 KiB
Groff
.\" $NetBSD: fpgetmask.3,v 1.10 2008/04/30 13:10:50 martin Exp $
|
|
.\"
|
|
.\" Copyright (c) 1999 The NetBSD Foundation, Inc.
|
|
.\" All rights reserved.
|
|
.\"
|
|
.\" This code is derived from software contributed to The NetBSD Foundation
|
|
.\" by Ross Harvey.
|
|
.\"
|
|
.\" Redistribution and use in source and binary forms, with or without
|
|
.\" modification, are permitted provided that the following conditions
|
|
.\" are met:
|
|
.\" 1. Redistributions of source code must retain the above copyright
|
|
.\" notice, this list of conditions and the following disclaimer.
|
|
.\" 2. Redistributions in binary form must reproduce the above copyright
|
|
.\" notice, this list of conditions and the following disclaimer in the
|
|
.\" documentation and/or other materials provided with the distribution.
|
|
.\"
|
|
.\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
|
|
.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
|
|
.\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
|
|
.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
|
|
.\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
|
|
.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
|
|
.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
|
|
.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
|
|
.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
|
|
.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
|
|
.\" POSSIBILITY OF SUCH DAMAGE.
|
|
.\"
|
|
.Dd April 4, 2004
|
|
.Dt FPGETMASK 3
|
|
.Os
|
|
.Sh NAME
|
|
.Nm fpgetmask ,
|
|
.Nm fpgetround ,
|
|
.Nm fpgetsticky ,
|
|
.Nm fpsetmask ,
|
|
.Nm fpsetround ,
|
|
.Nm fpsetsticky
|
|
.Nd IEEE FP mode control
|
|
.Sh LIBRARY
|
|
.Lb libc
|
|
.Sh SYNOPSIS
|
|
.In ieeefp.h
|
|
.Ft fp_except
|
|
.Fn fpgetmask void
|
|
.Ft fp_rnd
|
|
.Fn fpgetround void
|
|
.Ft fp_except
|
|
.Fn fpgetsticky void
|
|
.Ft fp_except
|
|
.Fn fpsetmask fp_except\ mask
|
|
.Ft fp_rnd
|
|
.Fn fpsetround fp_rnd\ rnd_dir
|
|
.Ft fp_except
|
|
.Fn fpsetsticky fp_except\ sticky
|
|
.Sh DESCRIPTION
|
|
A rounding mode is one of
|
|
.Dv FP_RZ , FP_RM , FP_RN ,
|
|
or
|
|
.Dv FP_RP ,
|
|
for rounding towards zero, rounding
|
|
.Pq Em Minus infinity
|
|
down, rounding to
|
|
.Em nearest ,
|
|
and rounding
|
|
.Pq Em Plus infinity
|
|
up.
|
|
The default mode is
|
|
.Dv FP_RN .
|
|
.Pp
|
|
An
|
|
.Ft fp_except
|
|
value is a bitmask specifying an exception type and containing any of
|
|
the values listed below.
|
|
.Bl -column -offset indent FP_X_UFLxx
|
|
.It Dv FP_X_INV Ta Invalid\ Operation
|
|
.It Dv FP_X_DZ Ta Division\ by\ zero
|
|
.It Dv FP_X_OFL Ta Overflow
|
|
.It Dv FP_X_UFL Ta Underflow
|
|
.It Dv FP_X_IMP Ta Imprecision (inexact)
|
|
.It Dv FP_X_IOV Ta Integer\ Overflow
|
|
.El
|
|
.Pp
|
|
The
|
|
.Fn fpsetmask
|
|
function will set the current exception mask, i.e., it will cause
|
|
future operations with the specified result status to raise the
|
|
.Dv SIGFPE
|
|
exception.
|
|
The
|
|
.Fn fpgetmask
|
|
function will return the current exception mask.
|
|
.Pp
|
|
The
|
|
.Fn fpsetround
|
|
function will cause future operations to use the specified dynamic
|
|
rounding mode.
|
|
The
|
|
.Fn fpgetround
|
|
function will return the current rounding mode.
|
|
.Bl -tag -width Note:x
|
|
.It Em Note :
|
|
On some architectures, instructions can optionally specify static
|
|
rounding modes and exception enables that will supersede the specified
|
|
dynamic mode.
|
|
On other architectures, these features may not be fully supported.
|
|
.El
|
|
.Pp
|
|
A
|
|
.Dq sticky
|
|
status word may be maintained in which a bit is set every time an
|
|
exceptional floating point condition is encountered, whether or not a
|
|
.Dv SIGFPE
|
|
is generated.
|
|
The
|
|
.Fn fpsetsticky
|
|
function will set or clear the specified exception history bits.
|
|
The
|
|
.Fn fpgetsticky
|
|
function will return the exception history bits.
|
|
.Sh RETURN VALUES
|
|
The
|
|
.Fn fpgetround
|
|
and
|
|
.Fn fpsetround
|
|
functions return the
|
|
.Pq previous
|
|
rounding mode.
|
|
The
|
|
.Fn fpgetmask ,
|
|
.Fn fpsetmask ,
|
|
.Fn fpgetsticky ,
|
|
and
|
|
.Fn fpsetsticky
|
|
functions return the
|
|
.Pq previous
|
|
exception mask and exception history bits.
|
|
.Sh SEE ALSO
|
|
.Xr sigaction 2
|