Define HIGH_ORDER_BIT_IS_SET_FOR_SNAN to 0 or 1.

This patch moves the HIGH_ORDER_BIT_IS_SET_FOR_SNAN macro from being
defined or undefined to the preferred convention of always being
defined, to either 0 or 1, so allowing typo-proof tests with #if.

The macro is moved from math_private.h to a new header
nan-high-order-bit.h to make it easy for all architectures to define,
either through the sysdeps/generic version of the header or through
providing their own version of the header, without needing #ifndef in
the generic math_private.h to give a default definition.  The move
also allows the macro to be used without needing math_private.h to be
included; the immediate motivation of this patch is to allow tests to
access this information (to know what kinds of NaNs 0 is a valid
payload for) without needing to include math_private.h.  Existing
C level rather than preprocessor conditionals at all, but this patch
does not make such a change).

Tested for x86_64 and x86 (testsuite); also verified for x86_64, x86,
mips64 and powerpc that installed stripped shared libraries are
unchanged by the patch.

	* sysdeps/generic/nan-high-order-bit.h: New file.
	* sysdeps/hppa/nan-high-order-bit.h: Likewise.
	* sysdeps/mips/nan-high-order-bit.h: Likewise.
	* sysdeps/hppa/math_private.h: Remove file.
	* sysdeps/mips/math_private.h (HIGH_ORDER_BIT_IS_SET_FOR_SNAN): Do
	not define here.
	* sysdeps/ieee754/dbl-64/s_issignaling.c: Include
	<nan-high-order-bit.h>.
	[HIGH_ORDER_BIT_IS_SET_FOR_SNAN]: Test with #if not #ifdef.
	* sysdeps/ieee754/dbl-64/s_totalorder.c: Include
	<nan-high-order-bit.h>.
	[HIGH_ORDER_BIT_IS_SET_FOR_SNAN]: Test with #if not #ifdef.
	* sysdeps/ieee754/dbl-64/s_totalordermag.c: Include
	<nan-high-order-bit.h>.
	[HIGH_ORDER_BIT_IS_SET_FOR_SNAN]: Test with #if not #ifdef.
	* sysdeps/ieee754/dbl-64/wordsize-64/s_issignaling.c: Include
	<nan-high-order-bit.h>.
	[HIGH_ORDER_BIT_IS_SET_FOR_SNAN]: Test with #if not #ifdef.
	* sysdeps/ieee754/dbl-64/wordsize-64/s_totalorder.c: Include
	<nan-high-order-bit.h>.
	[HIGH_ORDER_BIT_IS_SET_FOR_SNAN]: Test with #if not #ifdef.
	* sysdeps/ieee754/dbl-64/wordsize-64/s_totalordermag.c: Include
	<nan-high-order-bit.h>.
	[HIGH_ORDER_BIT_IS_SET_FOR_SNAN]: Test with #if not #ifdef.
	* sysdeps/ieee754/flt-32/s_issignalingf.c: Include
	<nan-high-order-bit.h>.
	[HIGH_ORDER_BIT_IS_SET_FOR_SNAN]: Test with #if not #ifdef.
	* sysdeps/ieee754/flt-32/s_totalorderf.c: Include
	<nan-high-order-bit.h>.
	[HIGH_ORDER_BIT_IS_SET_FOR_SNAN]: Test with #if not #ifdef.
	* sysdeps/ieee754/flt-32/s_totalordermagf.c: Include
	<nan-high-order-bit.h>.
	[HIGH_ORDER_BIT_IS_SET_FOR_SNAN]: Test with #if not #ifdef.
	* sysdeps/ieee754/ldbl-128/s_issignalingl.c: Include
	<nan-high-order-bit.h>.
	[HIGH_ORDER_BIT_IS_SET_FOR_SNAN]: Test with #if not #ifdef.
	* sysdeps/ieee754/ldbl-128/s_totalorderl.c: Include
	<nan-high-order-bit.h>.
	[HIGH_ORDER_BIT_IS_SET_FOR_SNAN]: Test with #if not #ifdef.
	* sysdeps/ieee754/ldbl-128/s_totalordermagl.c: Include
	<nan-high-order-bit.h>.
	[HIGH_ORDER_BIT_IS_SET_FOR_SNAN]: Test with #if not #ifdef.
	* sysdeps/ieee754/ldbl-128ibm/s_issignalingl.c: Include
	<nan-high-order-bit.h>.
	[HIGH_ORDER_BIT_IS_SET_FOR_SNAN]: Test with #if not #ifdef.
	* sysdeps/ieee754/ldbl-128ibm/s_totalorderl.c: Include
	<nan-high-order-bit.h>.
	[HIGH_ORDER_BIT_IS_SET_FOR_SNAN]: Test with #if not #ifdef.
	* sysdeps/ieee754/ldbl-128ibm/s_totalordermagl.c: Include
	<nan-high-order-bit.h>.
	[HIGH_ORDER_BIT_IS_SET_FOR_SNAN]: Test with #if not #ifdef.
	* sysdeps/ieee754/ldbl-96/s_issignalingl.c: Include
	<nan-high-order-bit.h>.
	[HIGH_ORDER_BIT_IS_SET_FOR_SNAN]: Test with #if not #ifdef.
	* sysdeps/ieee754/ldbl-96/s_totalorderl.c: Include
	<nan-high-order-bit.h>.
	[HIGH_ORDER_BIT_IS_SET_FOR_SNAN]: Test with #if not #ifdef.
	* sysdeps/ieee754/ldbl-96/s_totalordermagl.c: Include
	<nan-high-order-bit.h>.
	[HIGH_ORDER_BIT_IS_SET_FOR_SNAN]: Test with #if not #ifdef.

3 files changed, 6 insertions, 3 deletions

diff --git a/sysdeps/ieee754/ldbl-128ibm/s_issignalingl.c b/sysdeps/ieee754/ldbl-128ibm/s_issignalingl.c
index 091513908b..94cfffcd4b 100644
--- a/sysdeps/ieee754/ldbl-128ibm/s_issignalingl.c
+++ b/sysdeps/ieee754/ldbl-128ibm/s_issignalingl.c
@@ -18,6 +18,7 @@
 
 #include <math.h>
 #include <math_private.h>
+#include <nan-high-order-bit.h>
 
 int
 __issignalingl (long double x)
@@ -29,7 +30,7 @@ __issignalingl (long double x)
 
   xhi = ldbl_high (x);
   EXTRACT_WORDS64 (xi, xhi);
-#ifdef HIGH_ORDER_BIT_IS_SET_FOR_SNAN
+#if HIGH_ORDER_BIT_IS_SET_FOR_SNAN
 # error untested
   /* We only have to care about the high-order bit of x's significand, because
      having it set (sNaN) already makes the significand different from that
diff --git a/sysdeps/ieee754/ldbl-128ibm/s_totalorderl.c b/sysdeps/ieee754/ldbl-128ibm/s_totalorderl.c
index 1535b2fb1e..ff55779433 100644
--- a/sysdeps/ieee754/ldbl-128ibm/s_totalorderl.c
+++ b/sysdeps/ieee754/ldbl-128ibm/s_totalorderl.c
@@ -18,6 +18,7 @@
 
 #include <math.h>
 #include <math_private.h>
+#include <nan-high-order-bit.h>
 #include <stdint.h>
 
 int
@@ -30,7 +31,7 @@ totalorderl (long double x, long double y)
   EXTRACT_WORDS64 (hx, xhi);
   ldbl_unpack (y, &yhi, &ylo);
   EXTRACT_WORDS64 (hy, yhi);
-#ifdef HIGH_ORDER_BIT_IS_SET_FOR_SNAN
+#if HIGH_ORDER_BIT_IS_SET_FOR_SNAN
 # error not implemented
 #endif
   uint64_t hx_sign = hx >> 63;
diff --git a/sysdeps/ieee754/ldbl-128ibm/s_totalordermagl.c b/sysdeps/ieee754/ldbl-128ibm/s_totalordermagl.c
index 509a23a669..739e23194e 100644
--- a/sysdeps/ieee754/ldbl-128ibm/s_totalordermagl.c
+++ b/sysdeps/ieee754/ldbl-128ibm/s_totalordermagl.c
@@ -18,6 +18,7 @@
 
 #include <math.h>
 #include <math_private.h>
+#include <nan-high-order-bit.h>
 #include <stdint.h>
 
 int
@@ -30,7 +31,7 @@ totalordermagl (long double x, long double y)
   EXTRACT_WORDS64 (hx, xhi);
   ldbl_unpack (y, &yhi, &ylo);
   EXTRACT_WORDS64 (hy, yhi);
-#ifdef HIGH_ORDER_BIT_IS_SET_FOR_SNAN
+#if HIGH_ORDER_BIT_IS_SET_FOR_SNAN
 # error not implemented
 #endif
   uint64_t x_sign = hx & 0x8000000000000000ULL;