math: Remove fenvinline.h

Message ID 20200306175424.19827-1-adhemerval.zanella@linaro.org
State Superseded
Headers show
Series
  • math: Remove fenvinline.h
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Commit Message

Adhemerval Zanella March 6, 2020, 5:54 p.m.
Similar to string2.h (18b10de7ce) and string3.h (09a596cc2c) this
patch removes the fenvinline.h on all architectures.  Currently
only powerpc implements some optimization.

As for the strings optimization, this kind of optimization is
better implemented by the compiler (which handles the architecture
ISA transparently).

Also, for the specific optimized powerpc implementation the code is
becoming convoluted and these micro-optimization are hardly wildly
used, even more being a possible hotspot in realword cases
(non-default rounding are used only on specific cases and exception
handling are done most likely only on errors path).  The fact
that no other architecture bother to implement such optimization
is also an indication that these should no be on libc.

The math/test-fenv already covers all math/test-fenvinline tests,
so it is safe to remove it.

Checked on x86_64-linux-gnu and powerpc64le-linux-gnu.
---
 bits/fenvinline.h                 |   8 -
 math/Makefile                     |   4 +-
 math/fenv.h                       |   4 -
 math/test-fenvinline.c            | 354 ------------------------------
 sysdeps/powerpc/bits/fenvinline.h | 108 ---------
 5 files changed, 2 insertions(+), 476 deletions(-)
 delete mode 100644 bits/fenvinline.h
 delete mode 100644 math/test-fenvinline.c
 delete mode 100644 sysdeps/powerpc/bits/fenvinline.h

-- 
2.17.1

Comments

Tulio Magno Quites Machado Filho March 6, 2020, 6:08 p.m. | #1
Adhemerval Zanella <adhemerval.zanella@linaro.org> writes:

> Similar to string2.h (18b10de7ce) and string3.h (09a596cc2c) this

> patch removes the fenvinline.h on all architectures.  Currently

> only powerpc implements some optimization.

>

> As for the strings optimization, this kind of optimization is

> better implemented by the compiler (which handles the architecture

> ISA transparently).

>

> Also, for the specific optimized powerpc implementation the code is

> becoming convoluted and these micro-optimization are hardly wildly

> used, even more being a possible hotspot in realword cases

> (non-default rounding are used only on specific cases and exception

> handling are done most likely only on errors path).  The fact

> that no other architecture bother to implement such optimization

> is also an indication that these should no be on libc.

>

> The math/test-fenv already covers all math/test-fenvinline tests,

> so it is safe to remove it.

>

> Checked on x86_64-linux-gnu and powerpc64le-linux-gnu.


As has been mentioned in the previous thread [1]: I welcome this patch after the
proposed compiler features are implemented, but I don't think glibc
should remove fenvinline.h before that.

[1] https://www.sourceware.org/ml/libc-alpha/2020-03/msg00073.html

-- 
Tulio Magno
Adhemerval Zanella March 6, 2020, 6:47 p.m. | #2
On 06/03/2020 15:08, Tulio Magno Quites Machado Filho wrote:
> Adhemerval Zanella <adhemerval.zanella@linaro.org> writes:

> 

>> Similar to string2.h (18b10de7ce) and string3.h (09a596cc2c) this

>> patch removes the fenvinline.h on all architectures.  Currently

>> only powerpc implements some optimization.

>>

>> As for the strings optimization, this kind of optimization is

>> better implemented by the compiler (which handles the architecture

>> ISA transparently).

>>

>> Also, for the specific optimized powerpc implementation the code is

>> becoming convoluted and these micro-optimization are hardly wildly

>> used, even more being a possible hotspot in realword cases

>> (non-default rounding are used only on specific cases and exception

>> handling are done most likely only on errors path).  The fact

>> that no other architecture bother to implement such optimization

>> is also an indication that these should no be on libc.

>>

>> The math/test-fenv already covers all math/test-fenvinline tests,

>> so it is safe to remove it.

>>

>> Checked on x86_64-linux-gnu and powerpc64le-linux-gnu.

> 

> As has been mentioned in the previous thread [1]: I welcome this patch after the

> proposed compiler features are implemented, but I don't think glibc

> should remove fenvinline.h before that.

> 

> [1] https://www.sourceware.org/ml/libc-alpha/2020-03/msg00073.html

> 


Any real program actually benefits from this optimization, meaning
that fegetround/feraiseexcept/feclearexcept is being a hotspot? 
Also, why not adding other fenv functions, such as fetsetround
(since it the program is probing the rounding more, it most likely
want to set to a non-default)? 

Also, g++ disable such optimization on 
libstdc++-v3/include/c_compatibility/fenv.h, since it is not 
compatible with C++ (which is another indication that is really
does not make sense to continue exporting it).

The change of gcc is orthogonal to this one and I would like to
not encourage other ports to push for such optimization on glibc.
Paul E Murphy March 6, 2020, 7:36 p.m. | #3
On 3/6/20 11:54 AM, Adhemerval Zanella wrote:
> Similar to string2.h (18b10de7ce) and string3.h (09a596cc2c) this

> patch removes the fenvinline.h on all architectures.  Currently

> only powerpc implements some optimization.


Is that entirely accurate?  x86 looks like it places similar inline 
optimizations into bits/fenv.h, i.e feraiseexcept.

Should these instead move into the equivalent ppc bits/fenv.h header?

> 

> As for the strings optimization, this kind of optimization is

> better implemented by the compiler (which handles the architecture

> ISA transparently).

> 

> Also, for the specific optimized powerpc implementation the code is

> becoming convoluted and these micro-optimization are hardly wildly

> used, even more being a possible hotspot in realword cases

> (non-default rounding are used only on specific cases and exception

> handling are done most likely only on errors path).  The fact

> that no other architecture bother to implement such optimization

> is also an indication that these should no be on libc.

> 

> The math/test-fenv already covers all math/test-fenvinline tests,

> so it is safe to remove it.
Adhemerval Zanella March 9, 2020, 11:38 a.m. | #4
On 06/03/2020 16:36, Paul E Murphy wrote:
> 

> 

> On 3/6/20 11:54 AM, Adhemerval Zanella wrote:

>> Similar to string2.h (18b10de7ce) and string3.h (09a596cc2c) this

>> patch removes the fenvinline.h on all architectures.  Currently

>> only powerpc implements some optimization.

> 

> Is that entirely accurate?  x86 looks like it places similar inline optimizations into bits/fenv.h, i.e feraiseexcept.

> 

> Should these instead move into the equivalent ppc bits/fenv.h header?


Indeed, I will update the patch to remove these as well.

> 

>>

>> As for the strings optimization, this kind of optimization is

>> better implemented by the compiler (which handles the architecture

>> ISA transparently).

>>

>> Also, for the specific optimized powerpc implementation the code is

>> becoming convoluted and these micro-optimization are hardly wildly

>> used, even more being a possible hotspot in realword cases

>> (non-default rounding are used only on specific cases and exception

>> handling are done most likely only on errors path).  The fact

>> that no other architecture bother to implement such optimization

>> is also an indication that these should no be on libc.

>>

>> The math/test-fenv already covers all math/test-fenvinline tests,

>> so it is safe to remove it.

Patch

diff --git a/bits/fenvinline.h b/bits/fenvinline.h
deleted file mode 100644
index 42f77b5618..0000000000
--- a/bits/fenvinline.h
+++ /dev/null
@@ -1,8 +0,0 @@ 
-/* This file provides inline versions of floating-pint environment
-   handling functions.  If there were any.  */
-
-#ifndef __NO_MATH_INLINES
-
-/* Here is where the code would go.  */
-
-#endif
diff --git a/math/Makefile b/math/Makefile
index 84a8b94c74..f916594a51 100644
--- a/math/Makefile
+++ b/math/Makefile
@@ -24,7 +24,7 @@  include ../Makeconfig
 # Installed header files.
 headers		:= math.h bits/mathcalls.h bits/mathinline.h \
 		   fpu_control.h complex.h bits/cmathcalls.h fenv.h \
-		   bits/fenv.h bits/fenvinline.h bits/mathdef.h tgmath.h \
+		   bits/fenv.h bits/mathdef.h tgmath.h \
 		   bits/math-vector.h finclude/math-vector-fortran.h \
 		   bits/libm-simd-decl-stubs.h bits/iscanonical.h \
 		   bits/flt-eval-method.h bits/fp-fast.h bits/fp-logb.h \
@@ -233,7 +233,7 @@  tests = test-matherr-3 test-fenv basic-test \
 	test-misc test-fpucw test-fpucw-ieee tst-definitions test-tgmath \
 	test-tgmath-ret bug-nextafter bug-nexttoward bug-tgmath1 \
 	test-tgmath-int test-tgmath2 test-powl tst-CMPLX tst-CMPLX2 test-snan \
-	test-fenv-tls test-fenv-preserve test-fenv-return test-fenvinline \
+	test-fenv-tls test-fenv-preserve test-fenv-return \
 	test-nearbyint-except test-fenv-clear \
 	test-nearbyint-except-2 test-signgam-uchar test-signgam-uchar-init \
 	test-signgam-uint test-signgam-uint-init test-signgam-ullong \
diff --git a/math/fenv.h b/math/fenv.h
index 6cad1d3575..e6b9578d6c 100644
--- a/math/fenv.h
+++ b/math/fenv.h
@@ -140,10 +140,6 @@  extern int fegetmode (femode_t *__modep) __THROW;
 extern int fesetmode (const femode_t *__modep) __THROW;
 #endif
 
-/* Include optimization.  */
-#ifdef __OPTIMIZE__
-# include <bits/fenvinline.h>
-#endif
 
 /* NaN support.  */
 
diff --git a/math/test-fenvinline.c b/math/test-fenvinline.c
deleted file mode 100644
index 0e5d361fff..0000000000
--- a/math/test-fenvinline.c
+++ /dev/null
@@ -1,354 +0,0 @@ 
-/* Test for fenv inline implementations.
-   Copyright (C) 2015-2020 Free Software Foundation, Inc.
-   This file is part of the GNU C Library.
-
-   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.
-
-   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
-   <https://www.gnu.org/licenses/>.  */
-
-#ifndef _GNU_SOURCE
-# define _GNU_SOURCE
-#endif
-
-/* To make sure the fenv inline function are used.  */
-#undef __NO_MATH_INLINES
-
-#include <fenv.h>
-#include <stdio.h>
-#include <math-tests.h>
-
-/*
-  Since not all architectures might define all exceptions, we define
-  a private set and map accordingly.
-*/
-#define NO_EXC 0
-#define INEXACT_EXC 0x1
-#define DIVBYZERO_EXC 0x2
-#define UNDERFLOW_EXC 0x04
-#define OVERFLOW_EXC 0x08
-#define INVALID_EXC 0x10
-#define ALL_EXC \
-        (INEXACT_EXC | DIVBYZERO_EXC | UNDERFLOW_EXC | OVERFLOW_EXC \
-         | INVALID_EXC)
-static int count_errors;
-
-#if FE_ALL_EXCEPT
-static void
-test_single_exception_fp_int (int exception,
-			      int exc_flag,
-			      int fe_flag,
-			      const char *flag_name)
-{
-  if (exception & exc_flag)
-    {
-      if (fetestexcept (fe_flag))
-        printf ("  Pass: Exception \"%s\" is set\n", flag_name);
-      else
-        {
-          printf ("  Fail: Exception \"%s\" is not set\n", flag_name);
-          ++count_errors;
-        }
-    }
-  else
-    {
-      if (fetestexcept (fe_flag))
-        {
-          printf ("  Fail: Exception \"%s\" is set\n", flag_name);
-          ++count_errors;
-        }
-      else
-        printf ("  Pass: Exception \"%s\" is not set\n", flag_name);
-    }
-}
-/* Test whether a given exception was raised.  */
-static void
-test_single_exception_fp_double (int exception,
-				 int exc_flag,
-				 double fe_flag,
-				 const char *flag_name)
-{
-  if (exception & exc_flag)
-    {
-      if (fetestexcept (fe_flag))
-        printf ("  Pass: Exception \"%s\" is set\n", flag_name);
-      else
-        {
-          printf ("  Fail: Exception \"%s\" is not set\n", flag_name);
-          ++count_errors;
-        }
-    }
-  else
-    {
-      if (fetestexcept (fe_flag))
-        {
-          printf ("  Fail: Exception \"%s\" is set\n", flag_name);
-          ++count_errors;
-        }
-      else
-        printf ("  Pass: Exception \"%s\" is not set\n", flag_name);
-    }
-}
-#endif
-
-static void
-test_exceptions (const char *test_name, int exception)
-{
-  printf ("Test: %s\n", test_name);
-#ifdef FE_DIVBYZERO
-  test_single_exception_fp_double (exception, DIVBYZERO_EXC, FE_DIVBYZERO,
-				   "DIVBYZERO");
-#endif
-#ifdef FE_INVALID
-  test_single_exception_fp_double (exception, INVALID_EXC, FE_INVALID,
-				   "INVALID");
-#endif
-#ifdef FE_INEXACT
-  test_single_exception_fp_double (exception, INEXACT_EXC, FE_INEXACT,
-				   "INEXACT");
-#endif
-#ifdef FE_UNDERFLOW
-  test_single_exception_fp_double (exception, UNDERFLOW_EXC, FE_UNDERFLOW,
-				   "UNDERFLOW");
-#endif
-#ifdef FE_OVERFLOW
-  test_single_exception_fp_double (exception, OVERFLOW_EXC, FE_OVERFLOW,
-				   "OVERFLOW");
-#endif
-}
-
-static void
-test_exceptionflag (void)
-{
-  printf ("Test: fegetexceptionflag (FE_ALL_EXCEPT)\n");
-#if FE_ALL_EXCEPT
-  fexcept_t excepts;
-
-  feclearexcept (FE_ALL_EXCEPT);
-
-  feraiseexcept (FE_INVALID);
-  fegetexceptflag (&excepts, FE_ALL_EXCEPT);
-
-  feclearexcept (FE_ALL_EXCEPT);
-  feraiseexcept (FE_OVERFLOW | FE_INEXACT);
-
-  fesetexceptflag (&excepts, FE_ALL_EXCEPT);
-
-  test_single_exception_fp_int (INVALID_EXC, INVALID_EXC, FE_INVALID,
-				"INVALID (int)");
-  test_single_exception_fp_int (INVALID_EXC, OVERFLOW_EXC, FE_OVERFLOW,
-				"OVERFLOW (int)");
-  test_single_exception_fp_int (INVALID_EXC, INEXACT_EXC, FE_INEXACT,
-				"INEXACT (int)");
-
-  /* Same test, but using double as argument  */
-  feclearexcept (FE_ALL_EXCEPT);
-
-  feraiseexcept (FE_INVALID);
-  fegetexceptflag (&excepts, (double)FE_ALL_EXCEPT);
-
-  feclearexcept (FE_ALL_EXCEPT);
-  feraiseexcept (FE_OVERFLOW | FE_INEXACT);
-
-  fesetexceptflag (&excepts, (double)FE_ALL_EXCEPT);
-
-  test_single_exception_fp_double (INVALID_EXC, INVALID_EXC, FE_INVALID,
-				   "INVALID (double)");
-  test_single_exception_fp_double (INVALID_EXC, OVERFLOW_EXC, FE_OVERFLOW,
-				   "OVERFLOW (double)");
-  test_single_exception_fp_double (INVALID_EXC, INEXACT_EXC, FE_INEXACT,
-				   "INEXACT (double)");
-#endif
-}
-
-static void
-test_fesetround (void)
-{
-#if defined FE_TONEAREST && defined FE_TOWARDZERO
-  int res1;
-  int res2;
-
-  printf ("Tests for fesetround\n");
-
-  /* The fesetround should not itself cause the test to fail, however it
-     should either succeed for both 'int' and 'double' argument, or fail
-     for both.  */
-  res1 = fesetround ((int) FE_TOWARDZERO);
-  res2 = fesetround ((double) FE_TOWARDZERO);
-  if (res1 != res2)
-    {
-      printf ("fesetround (FE_TOWARDZERO) failed: %d, %d\n", res1, res2);
-      ++count_errors;
-    }
-
-  res1 = fesetround ((int) FE_TONEAREST);
-  res2 = fesetround ((double) FE_TONEAREST);
-  if (res1 != res2)
-    {
-      printf ("fesetround (FE_TONEAREST) failed: %d, %d\n", res1, res2);
-      ++count_errors;
-    }
-#endif
-}
-
-#if FE_ALL_EXCEPT
-/* Tests for feenableexcept/fedisableexcept.  */
-static void
-feenable_test (const char *flag_name, fexcept_t fe_exc)
-{
-  int fe_exci = fe_exc;
-  double fe_excd = fe_exc;
-  int excepts;
-
-  /* First disable all exceptions.  */
-  if (fedisableexcept (FE_ALL_EXCEPT) == -1)
-    {
-      printf ("Test: fedisableexcept (FE_ALL_EXCEPT) failed\n");
-      ++count_errors;
-      /* If this fails, the other tests don't make sense.  */
-      return;
-    }
-
-  /* Test for inline macros using integer argument.  */
-  excepts = feenableexcept (fe_exci);
-  if (!EXCEPTION_ENABLE_SUPPORTED (fe_exci) && excepts == -1)
-    {
-      printf ("Test: not testing feenableexcept, it isn't implemented.\n");
-      return;
-    }
-  if (excepts == -1)
-    {
-      printf ("Test: feenableexcept (%s) failed\n", flag_name);
-      ++count_errors;
-      return;
-    }
-  if (excepts != 0)
-    {
-      printf ("Test: feenableexcept (%s) failed, return should be 0, is %x\n",
-              flag_name, excepts);
-      ++count_errors;
-    }
-
-  /* And now disable the exception again.  */
-  excepts = fedisableexcept (fe_exc);
-  if (excepts == -1)
-    {
-      printf ("Test: fedisableexcept (%s) failed\n", flag_name);
-      ++count_errors;
-      return;
-    }
-  if (excepts != fe_exc)
-    {
-      printf ("Test: fedisableexcept (%s) failed, return should be 0x%x, is 0x%x\n",
-              flag_name, (unsigned int)fe_exc, excepts);
-      ++count_errors;
-    }
-
-  /* Test for inline macros using double argument.  */
-  excepts = feenableexcept (fe_excd);
-  if (!EXCEPTION_ENABLE_SUPPORTED (fe_excd) && excepts == -1)
-    {
-      printf ("Test: not testing feenableexcept, it isn't implemented.\n");
-      return;
-    }
-  if (excepts == -1)
-    {
-      printf ("Test: feenableexcept (%s) failed\n", flag_name);
-      ++count_errors;
-      return;
-    }
-  if (excepts != 0)
-    {
-      printf ("Test: feenableexcept (%s) failed, return should be 0, is %x\n",
-              flag_name, excepts);
-      ++count_errors;
-    }
-
-  /* And now disable the exception again.  */
-  excepts = fedisableexcept (fe_exc);
-  if (excepts == -1)
-    {
-      printf ("Test: fedisableexcept (%s) failed\n", flag_name);
-      ++count_errors;
-      return;
-    }
-  if (excepts != fe_exc)
-    {
-      printf ("Test: fedisableexcept (%s) failed, return should be 0x%x, is 0x%x\n",
-              flag_name, (unsigned int)fe_exc, excepts);
-      ++count_errors;
-    }
-}
-#endif
-
-static void
-test_feenabledisable (void)
-{
-  printf ("Tests for feenableexcepts/fedisableexcept\n");
-
-  /* We might have some exceptions still set.  */
-  feclearexcept (FE_ALL_EXCEPT);
-
-#ifdef FE_DIVBYZERO
-  feenable_test ("FE_DIVBYZERO", FE_DIVBYZERO);
-#endif
-#ifdef FE_INVALID
-  feenable_test ("FE_INVALID", FE_INVALID);
-#endif
-#ifdef FE_INEXACT
-  feenable_test ("FE_INEXACT", FE_INEXACT);
-#endif
-#ifdef FE_UNDERFLOW
-  feenable_test ("FE_UNDERFLOW", FE_UNDERFLOW);
-#endif
-#ifdef FE_OVERFLOW
-  feenable_test ("FE_OVERFLOW", FE_OVERFLOW);
-#endif
-  fesetenv (FE_DFL_ENV);
-}
-
-static int
-do_test (void)
-{
-  /* clear all exceptions and test if all are cleared  */
-  feclearexcept (FE_ALL_EXCEPT);
-  test_exceptions ("feclearexcept (FE_ALL_EXCEPT) clears all exceptions",
-                   NO_EXC);
-
-  /* raise all exceptions and test if all are raised  */
-  feraiseexcept (FE_ALL_EXCEPT);
-  if (EXCEPTION_TESTS (float))
-    test_exceptions ("feraiseexcept (FE_ALL_EXCEPT) raises all exceptions",
-		     ALL_EXC);
-
-  /* Same test, but using double as argument  */
-  feclearexcept ((double)FE_ALL_EXCEPT);
-  test_exceptions ("feclearexcept ((double)FE_ALL_EXCEPT) clears all exceptions",
-                   NO_EXC);
-
-  feraiseexcept ((double)FE_ALL_EXCEPT);
-  if (EXCEPTION_TESTS (float))
-    test_exceptions ("feraiseexcept ((double)FE_ALL_EXCEPT) raises all exceptions",
-		     ALL_EXC);
-
-  if (EXCEPTION_TESTS (float))
-    test_exceptionflag ();
-
-  test_fesetround ();
-
-  test_feenabledisable ();
-
-  return count_errors;
-}
-
-#define TEST_FUNCTION do_test ()
-#include "../test-skeleton.c"
diff --git a/sysdeps/powerpc/bits/fenvinline.h b/sysdeps/powerpc/bits/fenvinline.h
deleted file mode 100644
index f2d095a72f..0000000000
--- a/sysdeps/powerpc/bits/fenvinline.h
+++ /dev/null
@@ -1,108 +0,0 @@ 
-/* Inline floating-point environment handling functions for powerpc.
-   Copyright (C) 1995-2020 Free Software Foundation, Inc.
-   This file is part of the GNU C Library.
-
-   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.
-
-   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
-   <https://www.gnu.org/licenses/>.  */
-
-#if defined __GNUC__ && !defined _SOFT_FLOAT && !defined __NO_FPRS__
-
-/* Inline definitions for fegetround.  */
-# define __fegetround_ISA300()						\
-  (__extension__  ({							\
-    union { double __d; unsigned long long __ll; } __u;			\
-    __asm__ __volatile__ (						\
-      ".machine push; .machine \"power9\"; mffsl %0; .machine pop"	\
-      : "=f" (__u.__d));						\
-    __u.__ll & 0x0000000000000003LL;					\
-  }))
-
-# define __fegetround_ISA2()						\
-  (__extension__  ({							\
-     int __fegetround_result;						\
-     __asm__ __volatile__ ("mcrfs 7,7 ; mfcr %0"			\
-			   : "=r"(__fegetround_result) : : "cr7");	\
-     __fegetround_result & 3;						\
-  }))
-
-# ifdef _ARCH_PWR9
-#  define __fegetround() __fegetround_ISA300()
-# elif defined __BUILTIN_CPU_SUPPORTS__
-#  define __fegetround()						\
-  (__glibc_likely (__builtin_cpu_supports ("arch_3_00"))		\
-   ? __fegetround_ISA300()						\
-   : __fegetround_ISA2()						\
-  )
-# else
-#  define __fegetround() __fegetround_ISA2()
-# endif
-
-# define fegetround() __fegetround ()
-
-# ifndef __NO_MATH_INLINES
-
-/* Builtins to mtfsb0 and mtfsb1 was introduced on GCC 9.  */
-#  if !__GNUC_PREREQ(9, 0)
-/* The weird 'i#*X' constraints on the following suppress a gcc
-   warning when __excepts is not a constant.  Otherwise, they mean the
-   same as just plain 'i'.  This warning only happens in old GCC
-   versions (gcc 3 or less).  Otherwise plain 'i' works fine.  */
-#   define __MTFSB0(__b) __asm__ __volatile__ ("mtfsb0 %0" : : "i#*X" (__b))
-#   define __MTFSB1(__b) __asm__ __volatile__ ("mtfsb1 %0" : : "i#*X" (__b))
-#  else
-#   define __MTFSB0(__b) __builtin_mtfsb0 (__b)
-#   define __MTFSB1(__b) __builtin_mtfsb1 (__b)
-#  endif
-
-#  if __GNUC_PREREQ(3, 4)
-
-#include <sys/param.h>
-
-/* Inline definition for feraiseexcept.  */
-#   define feraiseexcept(__excepts) \
-  (__extension__  ({ 							      \
-    int __e = __excepts;						      \
-    int __ret = 0;							      \
-    if (__builtin_constant_p (__e)					      \
-        && __builtin_popcount (__e) == 1				      \
-        && __e != FE_INVALID)						      \
-      {									      \
-	__MTFSB1 ((__builtin_clz (__e)));				      \
-      }									      \
-    else								      \
-      __ret = feraiseexcept (__e);					      \
-    __ret;								      \
-  }))
-
-/* Inline definition for feclearexcept.  */
-#   define feclearexcept(__excepts) \
-  (__extension__  ({ 							      \
-    int __e = __excepts;						      \
-    int __ret = 0;							      \
-    if (__builtin_constant_p (__e)					      \
-        && __builtin_popcount (__e) == 1				      \
-        && __e != FE_INVALID)						      \
-      {									      \
-	__MTFSB0 ((__builtin_clz (__e)));				      \
-      }									      \
-    else								      \
-      __ret = feclearexcept (__e);					      \
-    __ret;								      \
-  }))
-
-#  endif /* __GNUC_PREREQ(3, 4).  */
-
-# endif /* !__NO_MATH_INLINES.  */
-
-#endif /* __GNUC__ && !_SOFT_FLOAT && !__NO_FPRS__ */