mirror of
git://sourceware.org/git/glibc.git
synced 2024-12-09 04:11:27 +08:00
7d67a196b6
This patch makes soft-fp use static assertions in place of conditional calls to abort, in places where there are checks for conditions (on the types for which a macro is used) that the code is not prepared to handle. The fallback definition of _FP_STATIC_ASSERT (for kernel use only, as only relevant to compilers not supported for building glibc) is as in misc/sys/cdefs.h. This means that soft-fp only ever calls abort for _FP_UNREACHABLE calls in builds with GCC versions before 4.5. Thus, there is no need for an abort declaration or <stdlib.h> include, since the kernel code handles defining abort as a macro itself - and so this avoids any need for an __KERNEL__ condition on the abort declaration to avoid it breaking with the kernel's macro definition. That is, this patch is intended to make glibc's soft-fp code suitable for kernel use with no kernel-local changes to the soft-fp code needed at all. Tested for powerpc-nofpu that installed stripped shared libraries are unchanged by the patch. One explicit <stdlib.h> include had to be added to a file that was relying on the include from soft-fp.h. * soft-fp/soft-fp.h (_FP_STATIC_ASSERT): New macro. [_LIBC]: Do not include <stdlib.h>. [!_LIBC] (abort): Remove declaration. * soft-fp/op-2.h (_FP_MUL_MEAT_2_120_240_double): Use _FP_STATIC_ASSERT instead of conditionally calling abort. * soft-fp/op-common.h (_FP_FROM_INT): Likewise. (_FP_EXTEND_CNAN): Likewise. (FP_TRUNC): Likewise. (__FP_CLZ): Likewise. * sysdeps/powerpc/nofpu/flt-rounds.c: Include <stdlib.h>.
355 lines
9.8 KiB
C
355 lines
9.8 KiB
C
/* Software floating-point emulation.
|
|
Copyright (C) 1997-2015 Free Software Foundation, Inc.
|
|
This file is part of the GNU C Library.
|
|
Contributed by Richard Henderson (rth@cygnus.com),
|
|
Jakub Jelinek (jj@ultra.linux.cz),
|
|
David S. Miller (davem@redhat.com) and
|
|
Peter Maydell (pmaydell@chiark.greenend.org.uk).
|
|
|
|
The GNU C 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 2.1 of the License, or (at your option) any later version.
|
|
|
|
In addition to the permissions in the GNU Lesser General Public
|
|
License, the Free Software Foundation gives you unlimited
|
|
permission to link the compiled version of this file into
|
|
combinations with other programs, and to distribute those
|
|
combinations without any restriction coming from the use of this
|
|
file. (The Lesser General Public License restrictions do apply in
|
|
other respects; for example, they cover modification of the file,
|
|
and distribution when not linked into a combine executable.)
|
|
|
|
The GNU C 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 the GNU C Library; if not, see
|
|
<http://www.gnu.org/licenses/>. */
|
|
|
|
#ifndef SOFT_FP_H
|
|
#define SOFT_FP_H 1
|
|
|
|
#ifdef _LIBC
|
|
# include <sfp-machine.h>
|
|
#elif defined __KERNEL__
|
|
/* The Linux kernel uses asm/ names for architecture-specific
|
|
files. */
|
|
# include <asm/sfp-machine.h>
|
|
#else
|
|
# include "sfp-machine.h"
|
|
#endif
|
|
|
|
/* Allow sfp-machine to have its own byte order definitions. */
|
|
#ifndef __BYTE_ORDER
|
|
# ifdef _LIBC
|
|
# include <endian.h>
|
|
# else
|
|
# error "endianness not defined by sfp-machine.h"
|
|
# endif
|
|
#endif
|
|
|
|
/* For unreachable default cases in switch statements over bitwise OR
|
|
of FP_CLS_* values. */
|
|
#if (defined __GNUC__ \
|
|
&& (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 5)))
|
|
# define _FP_UNREACHABLE __builtin_unreachable ()
|
|
#else
|
|
# define _FP_UNREACHABLE abort ()
|
|
#endif
|
|
|
|
#if ((defined __GNUC__ \
|
|
&& (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 6))) \
|
|
|| (defined __STDC_VERSION__ && __STDC_VERSION__ >= 201112L))
|
|
# define _FP_STATIC_ASSERT(expr, msg) \
|
|
_Static_assert ((expr), msg)
|
|
#else
|
|
# define _FP_STATIC_ASSERT(expr, msg) \
|
|
extern int (*__Static_assert_function (void)) \
|
|
[!!sizeof (struct { int __error_if_negative: (expr) ? 2 : -1; })]
|
|
#endif
|
|
|
|
/* In the Linux kernel, some architectures have a single function that
|
|
uses different kinds of unpacking and packing depending on the
|
|
instruction being emulated, meaning it is not readily visible to
|
|
the compiler that variables from _FP_DECL and _FP_FRAC_DECL_*
|
|
macros are only used in cases where they were initialized. */
|
|
#ifdef __KERNEL__
|
|
# define _FP_ZERO_INIT = 0
|
|
#else
|
|
# define _FP_ZERO_INIT
|
|
#endif
|
|
|
|
#define _FP_WORKBITS 3
|
|
#define _FP_WORK_LSB ((_FP_W_TYPE) 1 << 3)
|
|
#define _FP_WORK_ROUND ((_FP_W_TYPE) 1 << 2)
|
|
#define _FP_WORK_GUARD ((_FP_W_TYPE) 1 << 1)
|
|
#define _FP_WORK_STICKY ((_FP_W_TYPE) 1 << 0)
|
|
|
|
#ifndef FP_RND_NEAREST
|
|
# define FP_RND_NEAREST 0
|
|
# define FP_RND_ZERO 1
|
|
# define FP_RND_PINF 2
|
|
# define FP_RND_MINF 3
|
|
#endif
|
|
#ifndef FP_ROUNDMODE
|
|
# define FP_ROUNDMODE FP_RND_NEAREST
|
|
#endif
|
|
|
|
/* By default don't care about exceptions. */
|
|
#ifndef FP_EX_INVALID
|
|
# define FP_EX_INVALID 0
|
|
#endif
|
|
#ifndef FP_EX_OVERFLOW
|
|
# define FP_EX_OVERFLOW 0
|
|
#endif
|
|
#ifndef FP_EX_UNDERFLOW
|
|
# define FP_EX_UNDERFLOW 0
|
|
#endif
|
|
#ifndef FP_EX_DIVZERO
|
|
# define FP_EX_DIVZERO 0
|
|
#endif
|
|
#ifndef FP_EX_INEXACT
|
|
# define FP_EX_INEXACT 0
|
|
#endif
|
|
#ifndef FP_EX_DENORM
|
|
# define FP_EX_DENORM 0
|
|
#endif
|
|
|
|
/* Sub-exceptions of "invalid". */
|
|
/* Signaling NaN operand. */
|
|
#ifndef FP_EX_INVALID_SNAN
|
|
# define FP_EX_INVALID_SNAN 0
|
|
#endif
|
|
/* Inf * 0. */
|
|
#ifndef FP_EX_INVALID_IMZ
|
|
# define FP_EX_INVALID_IMZ 0
|
|
#endif
|
|
/* fma (Inf, 0, c). */
|
|
#ifndef FP_EX_INVALID_IMZ_FMA
|
|
# define FP_EX_INVALID_IMZ_FMA 0
|
|
#endif
|
|
/* Inf - Inf. */
|
|
#ifndef FP_EX_INVALID_ISI
|
|
# define FP_EX_INVALID_ISI 0
|
|
#endif
|
|
/* 0 / 0. */
|
|
#ifndef FP_EX_INVALID_ZDZ
|
|
# define FP_EX_INVALID_ZDZ 0
|
|
#endif
|
|
/* Inf / Inf. */
|
|
#ifndef FP_EX_INVALID_IDI
|
|
# define FP_EX_INVALID_IDI 0
|
|
#endif
|
|
/* sqrt (negative). */
|
|
#ifndef FP_EX_INVALID_SQRT
|
|
# define FP_EX_INVALID_SQRT 0
|
|
#endif
|
|
/* Invalid conversion to integer. */
|
|
#ifndef FP_EX_INVALID_CVI
|
|
# define FP_EX_INVALID_CVI 0
|
|
#endif
|
|
/* Invalid comparison. */
|
|
#ifndef FP_EX_INVALID_VC
|
|
# define FP_EX_INVALID_VC 0
|
|
#endif
|
|
|
|
/* _FP_STRUCT_LAYOUT may be defined as an attribute to determine the
|
|
struct layout variant used for structures where bit-fields are used
|
|
to access specific parts of binary floating-point numbers. This is
|
|
required for systems where the default ABI uses struct layout with
|
|
differences in how consecutive bit-fields are laid out from the
|
|
default expected by soft-fp. */
|
|
#ifndef _FP_STRUCT_LAYOUT
|
|
# define _FP_STRUCT_LAYOUT
|
|
#endif
|
|
|
|
#ifdef _FP_DECL_EX
|
|
# define FP_DECL_EX \
|
|
int _fex = 0; \
|
|
_FP_DECL_EX
|
|
#else
|
|
# define FP_DECL_EX int _fex = 0
|
|
#endif
|
|
|
|
/* Initialize any machine-specific state used in FP_ROUNDMODE,
|
|
FP_TRAPPING_EXCEPTIONS or FP_HANDLE_EXCEPTIONS. */
|
|
#ifndef FP_INIT_ROUNDMODE
|
|
# define FP_INIT_ROUNDMODE do {} while (0)
|
|
#endif
|
|
|
|
/* Initialize any machine-specific state used in
|
|
FP_TRAPPING_EXCEPTIONS or FP_HANDLE_EXCEPTIONS. */
|
|
#ifndef FP_INIT_TRAPPING_EXCEPTIONS
|
|
# define FP_INIT_TRAPPING_EXCEPTIONS FP_INIT_ROUNDMODE
|
|
#endif
|
|
|
|
/* Initialize any machine-specific state used in
|
|
FP_HANDLE_EXCEPTIONS. */
|
|
#ifndef FP_INIT_EXCEPTIONS
|
|
# define FP_INIT_EXCEPTIONS FP_INIT_TRAPPING_EXCEPTIONS
|
|
#endif
|
|
|
|
#ifndef FP_HANDLE_EXCEPTIONS
|
|
# define FP_HANDLE_EXCEPTIONS do {} while (0)
|
|
#endif
|
|
|
|
/* Whether to flush subnormal inputs to zero with the same sign. */
|
|
#ifndef FP_DENORM_ZERO
|
|
# define FP_DENORM_ZERO 0
|
|
#endif
|
|
|
|
#ifndef FP_INHIBIT_RESULTS
|
|
/* By default we write the results always.
|
|
sfp-machine may override this and e.g.
|
|
check if some exceptions are unmasked
|
|
and inhibit it in such a case. */
|
|
# define FP_INHIBIT_RESULTS 0
|
|
#endif
|
|
|
|
#define FP_SET_EXCEPTION(ex) \
|
|
_fex |= (ex)
|
|
|
|
#define FP_CUR_EXCEPTIONS \
|
|
(_fex)
|
|
|
|
#ifndef FP_TRAPPING_EXCEPTIONS
|
|
# define FP_TRAPPING_EXCEPTIONS 0
|
|
#endif
|
|
|
|
/* A file using soft-fp may define FP_NO_EXCEPTIONS before including
|
|
soft-fp.h to indicate that, although a macro used there could raise
|
|
exceptions, or do rounding and potentially thereby raise
|
|
exceptions, for some arguments, for the particular arguments used
|
|
in that file no exceptions or rounding can occur. Such a file
|
|
should not itself use macros relating to handling exceptions and
|
|
rounding modes; this is only for indirect uses (in particular, in
|
|
_FP_FROM_INT and the macros it calls). */
|
|
#ifdef FP_NO_EXCEPTIONS
|
|
|
|
# undef FP_SET_EXCEPTION
|
|
# define FP_SET_EXCEPTION(ex) do {} while (0)
|
|
|
|
# undef FP_CUR_EXCEPTIONS
|
|
# define FP_CUR_EXCEPTIONS 0
|
|
|
|
# undef FP_TRAPPING_EXCEPTIONS
|
|
# define FP_TRAPPING_EXCEPTIONS 0
|
|
|
|
# undef FP_ROUNDMODE
|
|
# define FP_ROUNDMODE FP_RND_ZERO
|
|
|
|
# undef _FP_TININESS_AFTER_ROUNDING
|
|
# define _FP_TININESS_AFTER_ROUNDING 0
|
|
|
|
#endif
|
|
|
|
/* A file using soft-fp may define FP_NO_EXACT_UNDERFLOW before
|
|
including soft-fp.h to indicate that, although a macro used there
|
|
could allow for the case of exact underflow requiring the underflow
|
|
exception to be raised if traps are enabled, for the particular
|
|
arguments used in that file no exact underflow can occur. */
|
|
#ifdef FP_NO_EXACT_UNDERFLOW
|
|
# undef FP_TRAPPING_EXCEPTIONS
|
|
# define FP_TRAPPING_EXCEPTIONS 0
|
|
#endif
|
|
|
|
#define _FP_ROUND_NEAREST(wc, X) \
|
|
do \
|
|
{ \
|
|
if ((_FP_FRAC_LOW_##wc (X) & 15) != _FP_WORK_ROUND) \
|
|
_FP_FRAC_ADDI_##wc (X, _FP_WORK_ROUND); \
|
|
} \
|
|
while (0)
|
|
|
|
#define _FP_ROUND_ZERO(wc, X) (void) 0
|
|
|
|
#define _FP_ROUND_PINF(wc, X) \
|
|
do \
|
|
{ \
|
|
if (!X##_s && (_FP_FRAC_LOW_##wc (X) & 7)) \
|
|
_FP_FRAC_ADDI_##wc (X, _FP_WORK_LSB); \
|
|
} \
|
|
while (0)
|
|
|
|
#define _FP_ROUND_MINF(wc, X) \
|
|
do \
|
|
{ \
|
|
if (X##_s && (_FP_FRAC_LOW_##wc (X) & 7)) \
|
|
_FP_FRAC_ADDI_##wc (X, _FP_WORK_LSB); \
|
|
} \
|
|
while (0)
|
|
|
|
#define _FP_ROUND(wc, X) \
|
|
do \
|
|
{ \
|
|
if (_FP_FRAC_LOW_##wc (X) & 7) \
|
|
{ \
|
|
FP_SET_EXCEPTION (FP_EX_INEXACT); \
|
|
switch (FP_ROUNDMODE) \
|
|
{ \
|
|
case FP_RND_NEAREST: \
|
|
_FP_ROUND_NEAREST (wc, X); \
|
|
break; \
|
|
case FP_RND_ZERO: \
|
|
_FP_ROUND_ZERO (wc, X); \
|
|
break; \
|
|
case FP_RND_PINF: \
|
|
_FP_ROUND_PINF (wc, X); \
|
|
break; \
|
|
case FP_RND_MINF: \
|
|
_FP_ROUND_MINF (wc, X); \
|
|
break; \
|
|
} \
|
|
} \
|
|
} \
|
|
while (0)
|
|
|
|
#define FP_CLS_NORMAL 0
|
|
#define FP_CLS_ZERO 1
|
|
#define FP_CLS_INF 2
|
|
#define FP_CLS_NAN 3
|
|
|
|
#define _FP_CLS_COMBINE(x, y) (((x) << 2) | (y))
|
|
|
|
#include "op-1.h"
|
|
#include "op-2.h"
|
|
#include "op-4.h"
|
|
#include "op-8.h"
|
|
#include "op-common.h"
|
|
|
|
/* Sigh. Silly things longlong.h needs. */
|
|
#define UWtype _FP_W_TYPE
|
|
#define W_TYPE_SIZE _FP_W_TYPE_SIZE
|
|
|
|
typedef int QItype __attribute__ ((mode (QI)));
|
|
typedef int SItype __attribute__ ((mode (SI)));
|
|
typedef int DItype __attribute__ ((mode (DI)));
|
|
typedef unsigned int UQItype __attribute__ ((mode (QI)));
|
|
typedef unsigned int USItype __attribute__ ((mode (SI)));
|
|
typedef unsigned int UDItype __attribute__ ((mode (DI)));
|
|
#if _FP_W_TYPE_SIZE == 32
|
|
typedef unsigned int UHWtype __attribute__ ((mode (HI)));
|
|
#elif _FP_W_TYPE_SIZE == 64
|
|
typedef USItype UHWtype;
|
|
#endif
|
|
|
|
#ifndef CMPtype
|
|
# define CMPtype int
|
|
#endif
|
|
|
|
#define SI_BITS (__CHAR_BIT__ * (int) sizeof (SItype))
|
|
#define DI_BITS (__CHAR_BIT__ * (int) sizeof (DItype))
|
|
|
|
#ifndef umul_ppmm
|
|
# ifdef _LIBC
|
|
# include <stdlib/longlong.h>
|
|
# else
|
|
# include "longlong.h"
|
|
# endif
|
|
#endif
|
|
|
|
#endif /* !SOFT_FP_H */
|