This is the mail archive of the glibc-cvs@sourceware.org mailing list for the glibc project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

GNU C Library master sources branch master updated. glibc-2.19-549-gf8ba1b5


This is an automated email from the git hooks/post-receive script. It was
generated because a ref change was pushed to the repository containing
the project "GNU C Library master sources".

The branch, master has been updated
       via  f8ba1b5654d876c8db4c9a020e6fa976d434f988 (commit)
      from  2c3520d98d9773d9e092196c3c36150244eed1dd (commit)

Those revisions listed above that are new to this repository have
not appeared on any other notification email; so we list those
revisions in full, below.

- Log -----------------------------------------------------------------
http://sourceware.org/git/gitweb.cgi?p=glibc.git;a=commitdiff;h=f8ba1b5654d876c8db4c9a020e6fa976d434f988

commit f8ba1b5654d876c8db4c9a020e6fa976d434f988
Author: Joseph Myers <joseph@codesourcery.com>
Date:   Tue Jun 10 12:07:15 2014 +0000

    Fix log2 (1) in round-downward mode (bug 17042).
    
    As with other issues of this kind, bug 17042 is log2 (1) wrongly
    returning -0 instead of +0 in round-downward mode because of
    implementations effectively in terms of log1p (x - 1).  This patch
    fixes the issue in the same way used for log and log10.
    
    Tested x86_64 and x86 and ulps updated accordingly.  Also tested for
    mips64 to confirm a fix was needed for ldbl-128 and to validate that
    fix (also applied to ldbl-128ibm since that version of log2l is
    essentially the same as the ldbl-128 one).
    
    	[BZ #17042]
    	* sysdeps/i386/fpu/e_log2.S (__ieee754_log2): Take absolete value
    	when x - 1 is zero.
    	* sysdeps/i386/fpu/e_log2f.S (__ieee754_log2f): Likewise.
    	* sysdeps/i386/fpu/e_log2l.S (__ieee754_log2l): Likewise.
    	* sysdeps/ieee754/ldbl-128/e_log2l.c (__ieee754_log2l): Return
    	0.0L for an argument of 1.0L.
    	* sysdeps/ieee754/ldbl-128ibm/e_log2l.c (__ieee754_log2l):
    	Likewise.
    	* sysdeps/x86_64/fpu/e_log2l.S (__ieee754_log2l): Take absolute
    	value when x - 1 is zero.
    	* math/libm-test.inc (log2_test): Use ALL_RM_TEST.
    	* sysdeps/i386/fpu/libm-test-ulps: Update.
    	* sysdeps/x86_64/fpu/libm-test-ulps: Likewise.

diff --git a/ChangeLog b/ChangeLog
index 0ace298..9055159 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,20 @@
+2014-06-10  Joseph Myers  <joseph@codesourcery.com>
+
+	[BZ #17042]
+	* sysdeps/i386/fpu/e_log2.S (__ieee754_log2): Take absolete value
+	when x - 1 is zero.
+	* sysdeps/i386/fpu/e_log2f.S (__ieee754_log2f): Likewise.
+	* sysdeps/i386/fpu/e_log2l.S (__ieee754_log2l): Likewise.
+	* sysdeps/ieee754/ldbl-128/e_log2l.c (__ieee754_log2l): Return
+	0.0L for an argument of 1.0L.
+	* sysdeps/ieee754/ldbl-128ibm/e_log2l.c (__ieee754_log2l):
+	Likewise.
+	* sysdeps/x86_64/fpu/e_log2l.S (__ieee754_log2l): Take absolute
+	value when x - 1 is zero.
+	* math/libm-test.inc (log2_test): Use ALL_RM_TEST.
+	* sysdeps/i386/fpu/libm-test-ulps: Update.
+	* sysdeps/x86_64/fpu/libm-test-ulps: Likewise.
+
 2014-06-09  Bernard Ogden  <bernie.ogden@linaro.org>
 
 	[BZ #15119]
diff --git a/NEWS b/NEWS
index 622cdbf..ca3ef63 100644
--- a/NEWS
+++ b/NEWS
@@ -19,7 +19,7 @@ Version 2.20
   16791, 16796, 16799, 16800, 16815, 16823, 16824, 16831, 16838, 16849,
   16854, 16876, 16877, 16878, 16882, 16885, 16888, 16890, 16912, 16915,
   16916, 16917, 16922, 16927, 16928, 16932, 16943, 16958, 16965, 16966,
-  16967, 16977, 16978, 16984, 16990, 17009.
+  16967, 16977, 16978, 16984, 16990, 17009, 17042.
 
 * The minimum Linux kernel version that this version of the GNU C Library
   can be used with is 2.6.32.
diff --git a/math/libm-test.inc b/math/libm-test.inc
index 0d467a2..fa8e238 100644
--- a/math/libm-test.inc
+++ b/math/libm-test.inc
@@ -7840,9 +7840,7 @@ static const struct test_f_f_data log2_test_data[] =
 static void
 log2_test (void)
 {
-  START (log2, 0);
-  RUN_TEST_LOOP_f_f (log2, log2_test_data, );
-  END;
+  ALL_RM_TEST (log2, 0, log2_test_data, RUN_TEST_LOOP_f_f, END);
 }
 
 
diff --git a/sysdeps/i386/fpu/e_log2.S b/sysdeps/i386/fpu/e_log2.S
index a202bc7..73ff0ff 100644
--- a/sysdeps/i386/fpu/e_log2.S
+++ b/sysdeps/i386/fpu/e_log2.S
@@ -47,7 +47,13 @@ ENTRY(__ieee754_log2)
 	fnstsw			// x-1 : x : 1
 	andb	$0x45, %ah
 	jz	2f
-	fstp	%st(1)		// x-1 : 1
+	fxam
+	fnstsw
+	andb	$0x45, %ah
+	cmpb	$0x40, %ah
+	jne	5f
+	fabs			// log2(1) is +0 in all rounding modes.
+5:	fstp	%st(1)		// x-1 : 1
 	fyl2xp1			// log(x)
 	ret
 
diff --git a/sysdeps/i386/fpu/e_log2f.S b/sysdeps/i386/fpu/e_log2f.S
index f4f9a8c..344eeb4 100644
--- a/sysdeps/i386/fpu/e_log2f.S
+++ b/sysdeps/i386/fpu/e_log2f.S
@@ -47,7 +47,13 @@ ENTRY(__ieee754_log2f)
 	fnstsw			// x-1 : x : 1
 	andb	$0x45, %ah
 	jz	2f
-	fstp	%st(1)		// x-1 : 1
+	fxam
+	fnstsw
+	andb	$0x45, %ah
+	cmpb	$0x40, %ah
+	jne	5f
+	fabs			// log2(1) is +0 in all rounding modes.
+5:	fstp	%st(1)		// x-1 : 1
 	fyl2xp1			// log(x)
 	ret
 
diff --git a/sysdeps/i386/fpu/e_log2l.S b/sysdeps/i386/fpu/e_log2l.S
index bd51b56..0f5f7e5 100644
--- a/sysdeps/i386/fpu/e_log2l.S
+++ b/sysdeps/i386/fpu/e_log2l.S
@@ -47,7 +47,13 @@ ENTRY(__ieee754_log2l)
 	fnstsw			// x-1 : x : 1
 	andb	$0x45, %ah
 	jz	2f
-	fstp	%st(1)		// x-1 : 1
+	fxam
+	fnstsw
+	andb	$0x45, %ah
+	cmpb	$0x40, %ah
+	jne	5f
+	fabs			// log2(1) is +0 in all rounding modes.
+5:	fstp	%st(1)		// x-1 : 1
 	fyl2xp1			// log(x)
 	ret
 
diff --git a/sysdeps/i386/fpu/libm-test-ulps b/sysdeps/i386/fpu/libm-test-ulps
index 1e89284..d7424a6 100644
--- a/sysdeps/i386/fpu/libm-test-ulps
+++ b/sysdeps/i386/fpu/libm-test-ulps
@@ -1588,6 +1588,22 @@ ifloat: 1
 ildouble: 1
 ldouble: 1
 
+Function: "log2_towardzero":
+double: 1
+float: 1
+idouble: 1
+ifloat: 1
+ildouble: 1
+ldouble: 1
+
+Function: "log2_upward":
+double: 1
+float: 1
+idouble: 1
+ifloat: 1
+ildouble: 1
+ldouble: 1
+
 Function: "log_downward":
 ildouble: 1
 ldouble: 1
diff --git a/sysdeps/ieee754/ldbl-128/e_log2l.c b/sysdeps/ieee754/ldbl-128/e_log2l.c
index 6c7da0e..991a3b7 100644
--- a/sysdeps/ieee754/ldbl-128/e_log2l.c
+++ b/sysdeps/ieee754/ldbl-128/e_log2l.c
@@ -188,6 +188,9 @@ __ieee754_log2l (x)
   if (hx >= 0x7fff000000000000LL)
     return (x + x);
 
+  if (x == 1.0L)
+    return 0.0L;
+
 /* separate mantissa from exponent */
 
 /* Note, frexp is used so that denormal numbers
diff --git a/sysdeps/ieee754/ldbl-128ibm/e_log2l.c b/sysdeps/ieee754/ldbl-128ibm/e_log2l.c
index 323ded0..442ad97 100644
--- a/sysdeps/ieee754/ldbl-128ibm/e_log2l.c
+++ b/sysdeps/ieee754/ldbl-128ibm/e_log2l.c
@@ -190,6 +190,9 @@ __ieee754_log2l (x)
   if (hx >= 0x7ff0000000000000LL)
     return (x + x);
 
+  if (x == 1.0L)
+    return 0.0L;
+
 /* separate mantissa from exponent */
 
 /* Note, frexp is used so that denormal numbers
diff --git a/sysdeps/x86_64/fpu/e_log2l.S b/sysdeps/x86_64/fpu/e_log2l.S
index 956489f..c12906d 100644
--- a/sysdeps/x86_64/fpu/e_log2l.S
+++ b/sysdeps/x86_64/fpu/e_log2l.S
@@ -45,7 +45,13 @@ ENTRY(__ieee754_log2l)
 	fnstsw			// x-1 : x : 1
 	andb	$0x45, %ah
 	jz	2f
-	fstp	%st(1)		// x-1 : 1
+	fxam
+	fnstsw
+	andb	$0x45, %ah
+	cmpb	$0x40, %ah
+	jne	5f
+	fabs			// log2(1) is +0 in all rounding modes.
+5:	fstp	%st(1)		// x-1 : 1
 	fyl2xp1			// log(x)
 	ret
 
diff --git a/sysdeps/x86_64/fpu/libm-test-ulps b/sysdeps/x86_64/fpu/libm-test-ulps
index bb549d2..92fef5a 100644
--- a/sysdeps/x86_64/fpu/libm-test-ulps
+++ b/sysdeps/x86_64/fpu/libm-test-ulps
@@ -1665,6 +1665,28 @@ ifloat: 1
 ildouble: 1
 ldouble: 1
 
+Function: "log2_downward":
+double: 2
+float: 2
+idouble: 2
+ifloat: 2
+
+Function: "log2_towardzero":
+double: 1
+float: 1
+idouble: 1
+ifloat: 1
+ildouble: 1
+ldouble: 1
+
+Function: "log2_upward":
+double: 2
+float: 2
+idouble: 2
+ifloat: 2
+ildouble: 1
+ldouble: 1
+
 Function: "log_downward":
 float: 1
 ifloat: 1

-----------------------------------------------------------------------

Summary of changes:
 ChangeLog                             |   17 +++++++++++++++++
 NEWS                                  |    2 +-
 math/libm-test.inc                    |    4 +---
 sysdeps/i386/fpu/e_log2.S             |    8 +++++++-
 sysdeps/i386/fpu/e_log2f.S            |    8 +++++++-
 sysdeps/i386/fpu/e_log2l.S            |    8 +++++++-
 sysdeps/i386/fpu/libm-test-ulps       |   16 ++++++++++++++++
 sysdeps/ieee754/ldbl-128/e_log2l.c    |    3 +++
 sysdeps/ieee754/ldbl-128ibm/e_log2l.c |    3 +++
 sysdeps/x86_64/fpu/e_log2l.S          |    8 +++++++-
 sysdeps/x86_64/fpu/libm-test-ulps     |   22 ++++++++++++++++++++++
 11 files changed, 91 insertions(+), 8 deletions(-)


hooks/post-receive
-- 
GNU C Library master sources


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]