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.

8 files changed, 56 insertions, 3 deletions

diff --git a/sysdeps/i386/fpu/s_asinh.S b/sysdeps/i386/fpu/s_asinh.S
index e4c0c67..7123772 100644
--- a/sysdeps/i386/fpu/s_asinh.S
+++ b/sysdeps/i386/fpu/s_asinh.S
@@ -100,7 +100,16 @@ ENTRY(__asinh)
 4:	fld	%st			// x : x
 	faddl	MO(huge)		// huge+x : x
 	fstp	%st(0)			// x
-	ret
+	cmpl	$0x00100000, %eax
+	jae	8f
+	subl	$8, %esp
+	cfi_adjust_cfa_offset (8)
+	fld	%st(0)
+	fmul	%st(0)
+	fstpl	(%esp)
+	addl	$8, %esp
+	cfi_adjust_cfa_offset (-8)
+8:	ret
 
 	// |x| > 2^28 => y = sign(x) * (log(|x|) + log(2))
 	.align ALIGNARG(4)
diff --git a/sysdeps/i386/fpu/s_asinhf.S b/sysdeps/i386/fpu/s_asinhf.S
index b1a28e7..77ebae4 100644
--- a/sysdeps/i386/fpu/s_asinhf.S
+++ b/sysdeps/i386/fpu/s_asinhf.S
@@ -100,7 +100,16 @@ ENTRY(__asinhf)
 4:	fld	%st			// x : x
 	faddl	MO(huge)		// huge+x : x
 	fstp	%st(0)			// x
-	ret
+	cmpl	$0x00800000, %eax
+	jae	8f
+	subl	$4, %esp
+	cfi_adjust_cfa_offset (4)
+	fld	%st(0)
+	fmul	%st(0)
+	fstps	(%esp)
+	addl	$4, %esp
+	cfi_adjust_cfa_offset (-4)
+8:	ret
 
 	// |x| > 2^14 => y = sign(x) * (log(|x|) + log(2))
 	.align ALIGNARG(4)
diff --git a/sysdeps/i386/fpu/s_asinhl.S b/sysdeps/i386/fpu/s_asinhl.S
index 6a5defe..8799da6 100644
--- a/sysdeps/i386/fpu/s_asinhl.S
+++ b/sysdeps/i386/fpu/s_asinhl.S
@@ -108,7 +108,12 @@ ENTRY(__asinhl)
 	fldt	MO(huge)		// huge : x : x
 	faddp				// huge+x : x
 	fstp	%st(0)			// x
-	ret
+	cmpl	$0x0001, %eax
+	jae	8f
+	fld	%st(0)
+	fmul	%st(0)
+	fstp	%st(0)
+8:	ret
 
 	// |x| > 2^34 => y = sign(x) * (log(|x|) + log(2))
 	.align ALIGNARG(4)
diff --git a/sysdeps/ieee754/dbl-64/s_asinh.c b/sysdeps/ieee754/dbl-64/s_asinh.c
index a33758d..ebe4710 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 b7fa2b4..697faa8 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 e5a3636..8d5721a 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 b76e114..dda7f78 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 5e679bd..75e47c7 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 */