Fix asinh missing underflows (bug 16350).

Similar to various other bugs in this area, some asinh implementations
do not raise the underflow exception for subnormal arguments, when the
result is tiny and inexact.  This patch forces the exception in a
similar way to previous fixes.

Tested for x86_64, x86 and mips64.

	[BZ #16350]
	* sysdeps/i386/fpu/s_asinh.S (__asinh): Force underflow exception
	for arguments with small absolute value.
	* sysdeps/i386/fpu/s_asinhf.S (__asinhf): Likewise.
	* sysdeps/i386/fpu/s_asinhl.S (__asinhl): Likewise.
	* sysdeps/ieee754/dbl-64/s_asinh.c: Include <float.h>.
	(__asinh): Force underflow exception for arguments with small
	absolute value.
	* sysdeps/ieee754/flt-32/s_asinhf.c: Include <float.h>.
	(__asinhf): Force underflow exception for arguments with small
	absolute value.
	* sysdeps/ieee754/ldbl-128/s_asinhl.c: Include <float.h>.
	(__asinhl): Force underflow exception for arguments with small
	absolute value.
	* sysdeps/ieee754/ldbl-128ibm/s_asinhl.c: Include <float.h>.
	(__asinhl): Force underflow exception for arguments with small
	absolute value.
	* sysdeps/ieee754/ldbl-96/s_asinhl.c: Include <float.h>.
	(__asinhl): Force underflow exception for arguments with small
	absolute value.
	* math/auto-libm-test-in: Do not mark underflow exceptions as
	possibly missing for bug 16350.
	* math/auto-libm-test-out: Regenerated.

5 files changed, 30 insertions, 0 deletions

diff --git a/sysdeps/ieee754/dbl-64/s_asinh.c b/sysdeps/ieee754/dbl-64/s_asinh.c
index a33758d3c9..ebe471015b 100644
--- a/sysdeps/ieee754/dbl-64/s_asinh.c
+++ b/sysdeps/ieee754/dbl-64/s_asinh.c
@@ -21,6 +21,7 @@
  *		 := sign(x)*log1p(|x| + x^2/(1 + sqrt(1+x^2)))
  */
 
+#include <float.h>
 #include <math.h>
 #include <math_private.h>
 
@@ -38,6 +39,11 @@ __asinh (double x)
   ix = hx & 0x7fffffff;
   if (__glibc_unlikely (ix < 0x3e300000))                  /* |x|<2**-28 */
     {
+      if (fabs (x) < DBL_MIN)
+	{
+	  double force_underflow = x * x;
+	  math_force_eval (force_underflow);
+	}
       if (huge + x > one)
 	return x;                       /* return x inexact except 0 */
     }
diff --git a/sysdeps/ieee754/flt-32/s_asinhf.c b/sysdeps/ieee754/flt-32/s_asinhf.c
index b7fa2b4443..697faa843c 100644
--- a/sysdeps/ieee754/flt-32/s_asinhf.c
+++ b/sysdeps/ieee754/flt-32/s_asinhf.c
@@ -13,6 +13,7 @@
  * ====================================================
  */
 
+#include <float.h>
 #include <math.h>
 #include <math_private.h>
 
@@ -29,6 +30,11 @@ __asinhf(float x)
 	GET_FLOAT_WORD(hx,x);
 	ix = hx&0x7fffffff;
 	if(__builtin_expect(ix< 0x38000000, 0)) {	/* |x|<2**-14 */
+	    if (fabsf (x) < FLT_MIN)
+	      {
+		float force_underflow = x * x;
+		math_force_eval (force_underflow);
+	      }
 	    if(huge+x>one) return x;	/* return x inexact except 0 */
 	}
 	if(__builtin_expect(ix>0x47000000, 0)) {	/* |x| > 2**14 */
diff --git a/sysdeps/ieee754/ldbl-128/s_asinhl.c b/sysdeps/ieee754/ldbl-128/s_asinhl.c
index e5a3636beb..8d5721a73c 100644
--- a/sysdeps/ieee754/ldbl-128/s_asinhl.c
+++ b/sysdeps/ieee754/ldbl-128/s_asinhl.c
@@ -29,6 +29,7 @@ static char rcsid[] = "$NetBSD: $";
  *                := signl(x)*log1pl(|x| + x^2/(1 + sqrtl(1+x^2)))
  */
 
+#include <float.h>
 #include <math.h>
 #include <math_private.h>
 
@@ -51,6 +52,11 @@ __asinhl (long double x)
     return x + x;		/* x is inf or NaN */
   if (ix < 0x3fc70000)
     {				/* |x| < 2^ -56 */
+      if (fabsl (x) < LDBL_MIN)
+	{
+	  long double force_underflow = x * x;
+	  math_force_eval (force_underflow);
+	}
       if (huge + x > one)
 	return x;		/* return x inexact except 0 */
     }
diff --git a/sysdeps/ieee754/ldbl-128ibm/s_asinhl.c b/sysdeps/ieee754/ldbl-128ibm/s_asinhl.c
index b76e114317..dda7f780fc 100644
--- a/sysdeps/ieee754/ldbl-128ibm/s_asinhl.c
+++ b/sysdeps/ieee754/ldbl-128ibm/s_asinhl.c
@@ -25,6 +25,7 @@ static char rcsid[] = "$NetBSD: s_asinh.c,v 1.9 1995/05/12 04:57:37 jtc Exp $";
  *		 := sign(x)*log1p(|x| + x^2/(1 + sqrt(1+x^2)))
  */
 
+#include <float.h>
 #include <math.h>
 #include <math_private.h>
 #include <math_ldbl_opt.h>
@@ -45,6 +46,11 @@ long double __asinhl(long double x)
 	ix = hx&0x7fffffffffffffffLL;
 	if(ix>=0x7ff0000000000000LL) return x+x;	/* x is inf or NaN */
 	if(ix< 0x3c70000000000000LL) {	/* |x|<2**-56 */
+	    if (fabsl (x) < LDBL_MIN)
+	      {
+		long double force_underflow = x * x;
+		math_force_eval (force_underflow);
+	      }
 	    if(huge+x>one) return x;	/* return x inexact except 0 */
 	}
 	if(ix>0x4370000000000000LL) {	/* |x| > 2**56 */
diff --git a/sysdeps/ieee754/ldbl-96/s_asinhl.c b/sysdeps/ieee754/ldbl-96/s_asinhl.c
index 5e679bd719..75e47c71ea 100644
--- a/sysdeps/ieee754/ldbl-96/s_asinhl.c
+++ b/sysdeps/ieee754/ldbl-96/s_asinhl.c
@@ -29,6 +29,7 @@ static char rcsid[] = "$NetBSD: $";
  *		  := signl(x)*log1pl(|x| + x^2/(1 + sqrtl(1+x^2)))
  */
 
+#include <float.h>
 #include <math.h>
 #include <math_private.h>
 
@@ -44,6 +45,11 @@ long double __asinhl(long double x)
 	GET_LDOUBLE_EXP(hx,x);
 	ix = hx&0x7fff;
 	if(__builtin_expect(ix< 0x3fde, 0)) {	/* |x|<2**-34 */
+	    if (fabsl (x) < LDBL_MIN)
+	      {
+		long double force_underflow = x * x;
+		math_force_eval (force_underflow);
+	      }
 	    if(huge+x>one) return x;	/* return x inexact except 0 */
 	}
 	if(__builtin_expect(ix>0x4020,0)) {		/* |x| > 2**34 */