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Move math_opt_barrier, math_force_eval to separate math-barriers.h [committed]
- From: Joseph Myers <joseph at codesourcery dot com>
- To: <libc-alpha at sourceware dot org>
- Date: Wed, 9 May 2018 19:47:03 +0000
- Subject: Move math_opt_barrier, math_force_eval to separate math-barriers.h [committed]
This patch continues cleaning up math_private.h by moving the
math_opt_barrier and math_force_eval macros to a separate header
math-barriers.h.
At present, those macros are inside a "#ifndef math_opt_barrier" in
math_private.h to allow architectures to override them and then use
#include_next to include the generic math_private.h. With the move to
a separate math-barriers.h header, no such #ifndef or #include_next is
needed; architectures just have their own alternative version of
math-barriers.h when providing their own optimized versions that avoid
going through memory unnecessarily. The generic math-barriers.h has a
comment added to document these two macros.
In this patch, math_private.h is made to #include <math-barriers.h>,
so files using these macros do not need updating yet. That is because
of uses of math_force_eval in math_check_force_underflow and
math_check_force_underflow_nonneg, which are still defined in
math_private.h. Once those are moved out to a separate header, that
separate header can be made to include <math-barriers.h>, as can the
other files directly using these barrier macros, and then the include
of <math-barriers.h> from math_private.h can be removed.
Tested for x86_64 and x86. Also tested with build-many-glibcs.py that
installed stripped shared libraries are unchanged by this patch.
Committed.
2018-05-09 Joseph Myers <joseph@codesourcery.com>
* sysdeps/generic/math-barriers.h: New file.
* sysdeps/generic/math_private.h [!math_opt_barrier]
(math_opt_barrier): Move to math-barriers.h.
[!math_opt_barrier] (math_force_eval): Likewise.
* sysdeps/aarch64/fpu/math-barriers.h: New file.
* sysdeps/aarch64/fpu/math_private.h (math_opt_barrier): Move to
math-barriers.h.
(math_force_eval): Likewise.
* sysdeps/alpha/fpu/math-barriers.h: New file.
* sysdeps/alpha/fpu/math_private.h (math_opt_barrier): Move to
math-barriers.h.
(math_force_eval): Likewise.
* sysdeps/x86/fpu/math-barriers.h: New file.
* sysdeps/i386/fpu/fenv_private.h (math_opt_barrier): Move to
math-barriers.h.
(math_force_eval): Likewise.
* sysdeps/m68k/m680x0/fpu/math_private.h: Move to....
* sysdeps/m68k/m680x0/fpu/math-barriers.h: ... here. Adjust
multiple-include guard for rename.
* sysdeps/powerpc/fpu/math-barriers.h: New file.
* sysdeps/powerpc/fpu/math_private.h (math_opt_barrier): Move to
math-barriers.h.
(math_force_eval): Likewise.
diff --git a/sysdeps/aarch64/fpu/math-barriers.h b/sysdeps/aarch64/fpu/math-barriers.h
new file mode 100644
index 0000000..7db937b
--- /dev/null
+++ b/sysdeps/aarch64/fpu/math-barriers.h
@@ -0,0 +1,27 @@
+/* Control when floating-point expressions are evaluated. AArch64 version.
+ Copyright (C) 2014-2018 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
+ <http://www.gnu.org/licenses/>. */
+
+#ifndef AARCH64_MATH_BARRIERS_H
+#define AARCH64_MATH_BARRIERS_H 1
+
+#define math_opt_barrier(x) \
+ ({ __typeof (x) __x = (x); __asm ("" : "+w" (__x)); __x; })
+#define math_force_eval(x) \
+ ({ __typeof (x) __x = (x); __asm __volatile__ ("" : : "w" (__x)); })
+
+#endif
diff --git a/sysdeps/aarch64/fpu/math_private.h b/sysdeps/aarch64/fpu/math_private.h
index d9c2d71..fcd02c0 100644
--- a/sysdeps/aarch64/fpu/math_private.h
+++ b/sysdeps/aarch64/fpu/math_private.h
@@ -22,11 +22,6 @@
#include <fenv.h>
#include <fpu_control.h>
-#define math_opt_barrier(x) \
-({ __typeof (x) __x = (x); __asm ("" : "+w" (__x)); __x; })
-#define math_force_eval(x) \
-({ __typeof (x) __x = (x); __asm __volatile__ ("" : : "w" (__x)); })
-
static __always_inline void
libc_feholdexcept_aarch64 (fenv_t *envp)
{
diff --git a/sysdeps/alpha/fpu/math-barriers.h b/sysdeps/alpha/fpu/math-barriers.h
new file mode 100644
index 0000000..27a64d7
--- /dev/null
+++ b/sysdeps/alpha/fpu/math-barriers.h
@@ -0,0 +1,28 @@
+/* Control when floating-point expressions are evaluated. Alpha version.
+ Copyright (C) 2014-2018 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
+ <http://www.gnu.org/licenses/>. */
+
+#ifndef ALPHA_MATH_BARRIERS_H
+#define ALPHA_MATH_BARRIERS_H 1
+
+/* Generic code forces values to memory; we don't need to do that. */
+#define math_opt_barrier(x) \
+ ({ __typeof (x) __x = (x); __asm ("" : "+frm" (__x)); __x; })
+#define math_force_eval(x) \
+ ({ __typeof (x) __x = (x); __asm __volatile__ ("" : : "frm" (__x)); })
+
+#endif
diff --git a/sysdeps/alpha/fpu/math_private.h b/sysdeps/alpha/fpu/math_private.h
index 95dc32c..c71447a 100644
--- a/sysdeps/alpha/fpu/math_private.h
+++ b/sysdeps/alpha/fpu/math_private.h
@@ -13,12 +13,6 @@
# define __isnanf __isnanf
#endif
-/* Generic code forces values to memory; we don't need to do that. */
-#define math_opt_barrier(x) \
- ({ __typeof (x) __x = (x); __asm ("" : "+frm" (__x)); __x; })
-#define math_force_eval(x) \
- ({ __typeof (x) __x = (x); __asm __volatile__ ("" : : "frm" (__x)); })
-
#include_next <math_private.h>
#endif /* ALPHA_MATH_PRIVATE_H */
diff --git a/sysdeps/generic/math-barriers.h b/sysdeps/generic/math-barriers.h
new file mode 100644
index 0000000..4251731
--- /dev/null
+++ b/sysdeps/generic/math-barriers.h
@@ -0,0 +1,37 @@
+/* Control when floating-point expressions are evaluated. Generic version.
+ Copyright (C) 2007-2018 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
+ <http://www.gnu.org/licenses/>. */
+
+#ifndef _MATH_BARRIERS_H
+#define _MATH_BARRIERS_H 1
+
+/* math_opt_barrier evaluates and returns its floating-point argument
+ and ensures that the evaluation of any expression using the result
+ of math_opt_barrier is not moved before the call. math_force_eval
+ ensures that its floating-point argument is evaluated for its side
+ effects even if its value is apparently unused, and that the
+ evaluation of its argument is not moved after the call. Both these
+ macros are used to ensure the correct ordering of floating-point
+ expression evaluations with respect to accesses to the
+ floating-point environment. */
+
+#define math_opt_barrier(x) \
+ ({ __typeof (x) __x = (x); __asm ("" : "+m" (__x)); __x; })
+#define math_force_eval(x) \
+ ({ __typeof (x) __x = (x); __asm __volatile__ ("" : : "m" (__x)); })
+
+#endif /* math-barriers.h */
diff --git a/sysdeps/generic/math_private.h b/sysdeps/generic/math_private.h
index 703f506..f6faf71 100644
--- a/sysdeps/generic/math_private.h
+++ b/sysdeps/generic/math_private.h
@@ -263,12 +263,7 @@ extern double __mpsin (double __x, double __dx, bool __range_reduce);
extern double __mpcos (double __x, double __dx, bool __range_reduce);
extern void __docos (double __x, double __dx, double __v[]);
-#ifndef math_opt_barrier
-# define math_opt_barrier(x) \
-({ __typeof (x) __x = (x); __asm ("" : "+m" (__x)); __x; })
-# define math_force_eval(x) \
-({ __typeof (x) __x = (x); __asm __volatile__ ("" : : "m" (__x)); })
-#endif
+#include <math-barriers.h>
#define fabs_tg(x) __MATH_TG ((x), (__typeof (x)) __builtin_fabs, (x))
diff --git a/sysdeps/i386/fpu/fenv_private.h b/sysdeps/i386/fpu/fenv_private.h
index 357613a..59e83d8 100644
--- a/sysdeps/i386/fpu/fenv_private.h
+++ b/sysdeps/i386/fpu/fenv_private.h
@@ -5,45 +5,6 @@
#include <fenv.h>
#include <fpu_control.h>
-#ifdef __SSE2_MATH__
-# define math_opt_barrier(x) \
- ({ __typeof(x) __x; \
- if (sizeof (x) <= sizeof (double) \
- || __builtin_types_compatible_p (__typeof (x), _Float128)) \
- __asm ("" : "=x" (__x) : "0" (x)); \
- else \
- __asm ("" : "=t" (__x) : "0" (x)); \
- __x; })
-# define math_force_eval(x) \
- do { \
- if (sizeof (x) <= sizeof (double) \
- || __builtin_types_compatible_p (__typeof (x), _Float128)) \
- __asm __volatile ("" : : "x" (x)); \
- else \
- __asm __volatile ("" : : "f" (x)); \
- } while (0)
-#else
-# define math_opt_barrier(x) \
- ({ __typeof (x) __x; \
- if (__builtin_types_compatible_p (__typeof (x), _Float128)) \
- { \
- __x = (x); \
- __asm ("" : "+m" (__x)); \
- } \
- else \
- __asm ("" : "=t" (__x) : "0" (x)); \
- __x; })
-# define math_force_eval(x) \
- do { \
- __typeof (x) __x = (x); \
- if (sizeof (x) <= sizeof (double) \
- || __builtin_types_compatible_p (__typeof (x), _Float128)) \
- __asm __volatile ("" : : "m" (__x)); \
- else \
- __asm __volatile ("" : : "f" (__x)); \
- } while (0)
-#endif
-
/* This file is used by both the 32- and 64-bit ports. The 64-bit port
has a field in the fenv_t for the mxcsr; the 32-bit port does not.
Instead, we (ab)use the only 32-bit field extant in the struct. */
diff --git a/sysdeps/m68k/m680x0/fpu/math-barriers.h b/sysdeps/m68k/m680x0/fpu/math-barriers.h
new file mode 100644
index 0000000..b1b78d5
--- /dev/null
+++ b/sysdeps/m68k/m680x0/fpu/math-barriers.h
@@ -0,0 +1,37 @@
+/* Control when floating-point expressions are evaluated. M68k version.
+ Copyright (C) 2011-2018 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
+ <http://www.gnu.org/licenses/>. */
+
+#ifndef M68K_MATH_BARRIERS_H
+#define M68K_MATH_BARRIERS_H 1
+
+#define math_opt_barrier(x) \
+({ __typeof (x) __x; \
+ __asm ("" : "=f" (__x) : "0" (x)); \
+ __x; })
+#define math_force_eval(x) \
+do \
+ { \
+ __typeof (x) __x = (x); \
+ if (sizeof (x) <= sizeof (double)) \
+ __asm __volatile ("" : : "m" (__x)); \
+ else \
+ __asm __volatile ("" : : "f" (__x)); \
+ } \
+while (0)
+
+#endif
diff --git a/sysdeps/m68k/m680x0/fpu/math_private.h b/sysdeps/m68k/m680x0/fpu/math_private.h
deleted file mode 100644
index 2b79095..0000000
--- a/sysdeps/m68k/m680x0/fpu/math_private.h
+++ /dev/null
@@ -1,20 +0,0 @@
-#ifndef M68K_MATH_PRIVATE_H
-#define M68K_MATH_PRIVATE_H 1
-
-#define math_opt_barrier(x) \
-({ __typeof (x) __x; \
- __asm ("" : "=f" (__x) : "0" (x)); \
- __x; })
-#define math_force_eval(x) \
-do \
- { \
- __typeof (x) __x = (x); \
- if (sizeof (x) <= sizeof (double)) \
- __asm __volatile ("" : : "m" (__x)); \
- else \
- __asm __volatile ("" : : "f" (__x)); \
- } \
-while (0)
-
-#include_next <math_private.h>
-#endif
diff --git a/sysdeps/powerpc/fpu/math-barriers.h b/sysdeps/powerpc/fpu/math-barriers.h
new file mode 100644
index 0000000..6da2102
--- /dev/null
+++ b/sysdeps/powerpc/fpu/math-barriers.h
@@ -0,0 +1,28 @@
+/* Control when floating-point expressions are evaluated. PowerPC version.
+ Copyright (C) 2017-2018 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
+ <http://www.gnu.org/licenses/>. */
+
+#ifndef POWERPC_MATH_BARRIERS_H
+#define POWERPC_MATH_BARRIERS_H 1
+
+/* Avoid putting floating point values in memory. */
+# define math_opt_barrier(x) \
+ ({ __typeof (x) __x = (x); __asm ("" : "+dwa" (__x)); __x; })
+# define math_force_eval(x) \
+ ({ __typeof (x) __x = (x); __asm __volatile__ ("" : : "dwa" (__x)); })
+
+#endif
diff --git a/sysdeps/powerpc/fpu/math_private.h b/sysdeps/powerpc/fpu/math_private.h
index b9fc721..e642d6c 100644
--- a/sysdeps/powerpc/fpu/math_private.h
+++ b/sysdeps/powerpc/fpu/math_private.h
@@ -24,12 +24,6 @@
#include <dl-procinfo.h>
#include <fenv_private.h>
-/* Avoid putting floating point values in memory. */
-# define math_opt_barrier(x) \
- ({ __typeof (x) __x = (x); __asm ("" : "+dwa" (__x)); __x; })
-# define math_force_eval(x) \
- ({ __typeof (x) __x = (x); __asm __volatile__ ("" : : "dwa" (__x)); })
-
#include_next <math_private.h>
#if defined _ARCH_PWR9 && __HAVE_DISTINCT_FLOAT128
diff --git a/sysdeps/x86/fpu/math-barriers.h b/sysdeps/x86/fpu/math-barriers.h
new file mode 100644
index 0000000..1e1fabd
--- /dev/null
+++ b/sysdeps/x86/fpu/math-barriers.h
@@ -0,0 +1,61 @@
+/* Control when floating-point expressions are evaluated. x86 version.
+ Copyright (C) 2007-2018 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
+ <http://www.gnu.org/licenses/>. */
+
+#ifndef X86_MATH_BARRIERS_H
+#define X86_MATH_BARRIERS_H 1
+
+#ifdef __SSE2_MATH__
+# define math_opt_barrier(x) \
+ ({ __typeof(x) __x; \
+ if (sizeof (x) <= sizeof (double) \
+ || __builtin_types_compatible_p (__typeof (x), _Float128)) \
+ __asm ("" : "=x" (__x) : "0" (x)); \
+ else \
+ __asm ("" : "=t" (__x) : "0" (x)); \
+ __x; })
+# define math_force_eval(x) \
+ do { \
+ if (sizeof (x) <= sizeof (double) \
+ || __builtin_types_compatible_p (__typeof (x), _Float128)) \
+ __asm __volatile ("" : : "x" (x)); \
+ else \
+ __asm __volatile ("" : : "f" (x)); \
+ } while (0)
+#else
+# define math_opt_barrier(x) \
+ ({ __typeof (x) __x; \
+ if (__builtin_types_compatible_p (__typeof (x), _Float128)) \
+ { \
+ __x = (x); \
+ __asm ("" : "+m" (__x)); \
+ } \
+ else \
+ __asm ("" : "=t" (__x) : "0" (x)); \
+ __x; })
+# define math_force_eval(x) \
+ do { \
+ __typeof (x) __x = (x); \
+ if (sizeof (x) <= sizeof (double) \
+ || __builtin_types_compatible_p (__typeof (x), _Float128)) \
+ __asm __volatile ("" : : "m" (__x)); \
+ else \
+ __asm __volatile ("" : : "f" (__x)); \
+ } while (0)
+#endif
+
+#endif
--
Joseph S. Myers
joseph@codesourcery.com