[PATCH] Fix for logb/logbf/logbl (bz 13954/13955/13956)

[David Miller]

From: Adhemerval Zanella <azanella@linux.vnet.ibm.com>
Date: Fri, 04 May 2012 12:30:09 -0300

> 2012-05-04  Adhemerval Zanella  <azanella@linux.vnet.ibm.com>
> 
> 	[BZ #13954]
> 	[BZ #13955]
> 	[BZ #13956]
> 	* sysdeps/ieee754/dbl-64/s_logb.c (__logb): Fix for subnormal number.
> 	* sysdeps/ieee754/dbl-64/wordsize-64/s_logb.c (__logb): Likewise.
> 	* sysdeps/ieee754/flt-32/s_logbf.c (__logf): Likewise.
> 	* sysdeps/ieee754/ldbl-128/s_logbl.c (__logbl): Likewise.
> 	* sysdeps/ieee754/ldbl-128ibm/s_logbl.c (__logbl): Likewise.
> 	* sysdeps/ieee754/ldbl-96/s_logbl.c (__logbl): Likewise.
> 	* math/libm-test.inc (logb_test) : Additional logb tests.

This works fine on sparc.