Move math_opt_barrier, math_force_eval to separate math-barriers.h.

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
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.

	* 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.

1 files changed, 26 insertions, 0 deletions

diff --git a/ChangeLog b/ChangeLog
index 4164b32036..7ab225e320 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,29 @@
+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.
+
 2018-05-09  Paul Pluzhnikov  <ppluzhnikov@google.com>
 
 	[BZ #22786]