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Re: PATCH: PR math/12775: Typo in sysdeps/x86_64/fpu/e_powl.S


On Wed, May 18, 2011 at 11:35 AM, Jakub Jelinek <jakub@redhat.com> wrote:
> On Wed, May 18, 2011 at 09:30:03AM -0700, H.J. Lu wrote:
>> @@ -90,7 +90,8 @@ distribute += $(filter-out $(generated),$(long-m-yes:=.c) $(long-c-yes:=.c))
>> ?# Rules for the test suite.
>> ?tests = test-matherr test-fenv atest-exp atest-sincos atest-exp2 basic-test \
>> ? ? ? test-misc test-fpucw tst-definitions test-tgmath test-tgmath-ret \
>> - ? ? bug-nextafter bug-nexttoward bug-tgmath1 test-tgmath-int test-tgmath2
>> + ? ? bug-nextafter bug-nexttoward bug-tgmath1 test-tgmath-int \
>> + ? ? test-tgmath2 test-powl
>> ?# We do the `long double' tests only if this data type is available and
>> ?# distinct from `double'.
>> ?test-longdouble-yes = test-ldouble test-ildoubl
>> @@ -131,12 +132,14 @@ CFLAGS-test-ldouble.c = -fno-inline -ffloat-store -fno-builtin
>> ?CFLAGS-test-tgmath.c = -fno-builtin
>> ?CFLAGS-test-tgmath2.c = -fno-builtin
>> ?CFLAGS-test-tgmath-ret.c = -fno-builtin
>> +CFLAGS-test-powl.c = -O0
>
> Why not -fno-builtin instead of -O0?
>
>> +#ifndef NO_LONG_DOUBLE
>> + ? ?{
>> + ? ? ?long double x = 1e-20;
>> + ? ? ?union ieee854_long_double u;
>> + ? ? ?u.ieee.mantissa0 = 1;
>> + ? ? ?u.ieee.mantissa1 = 1;
>> + ? ? ?u.ieee.exponent = 0;
>> + ? ? ?u.ieee.negative = 0;
>
> This won't work correctly for IEEE quad long double or IBM double double.
> So, either you should add the test for extended long double only, or
> add guards here for extended long double too (e.g. LDBL_MANT_DIG == 64).
>
> ? ? ? ?Jakub
>

Here is the updated patch.

Thanks.

-- 
H.J.
----
2011-05-18  H.J. Lu  <hongjiu.lu@intel.com>

	PR math/12775
	* math/Makefile (tests): Add test-powl.
	(CFLAGS-test-powl.c): New.

	* math/test-powl.c: New.

	* sysdeps/x86_64/fpu/e_powl.S: Fix a typo.
2011-05-18  H.J. Lu  <hongjiu.lu@intel.com>

	PR math/12775
	* math/Makefile (tests): Add test-powl.
	(CFLAGS-test-powl.c): New.

	* math/test-powl.c: New.

	* sysdeps/x86_64/fpu/e_powl.S: Fix a typo.

diff --git a/math/Makefile b/math/Makefile
index 7e3a626..45954e2 100644
--- a/math/Makefile
+++ b/math/Makefile
@@ -90,7 +90,8 @@ distribute += $(filter-out $(generated),$(long-m-yes:=.c) $(long-c-yes:=.c))
 # Rules for the test suite.
 tests = test-matherr test-fenv atest-exp atest-sincos atest-exp2 basic-test \
 	test-misc test-fpucw tst-definitions test-tgmath test-tgmath-ret \
-	bug-nextafter bug-nexttoward bug-tgmath1 test-tgmath-int test-tgmath2
+	bug-nextafter bug-nexttoward bug-tgmath1 test-tgmath-int \
+	test-tgmath2 test-powl
 # We do the `long double' tests only if this data type is available and
 # distinct from `double'.
 test-longdouble-yes = test-ldouble test-ildoubl
@@ -131,6 +132,7 @@ CFLAGS-test-ldouble.c = -fno-inline -ffloat-store -fno-builtin
 CFLAGS-test-tgmath.c = -fno-builtin
 CFLAGS-test-tgmath2.c = -fno-builtin
 CFLAGS-test-tgmath-ret.c = -fno-builtin
+CFLAGS-test-powl.c = -fno-builtin
 CPPFLAGS-test-ifloat.c = -U__LIBC_INTERNAL_MATH_INLINES -D__FAST_MATH__ \
 			 -DTEST_FAST_MATH -fno-builtin
 CPPFLAGS-test-idouble.c = -U__LIBC_INTERNAL_MATH_INLINES -D__FAST_MATH__ \
diff --git a/math/test-powl.c b/math/test-powl.c
new file mode 100644
index 0000000..960f216
--- /dev/null
+++ b/math/test-powl.c
@@ -0,0 +1,51 @@
+/* Test for powl
+   Copyright (C) 2011 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <stdio.h>
+#include <math.h>
+#include <float.h>
+#include <ieee754.h>
+
+int
+main (void)
+{
+  int result = 0;
+
+#ifndef NO_LONG_DOUBLE
+# if LDBL_MANT_DIG == 64
+    {
+      long double x = 1e-20;
+      union ieee854_long_double u;
+      u.ieee.mantissa0 = 1;
+      u.ieee.mantissa1 = 1;
+      u.ieee.exponent = 0;
+      u.ieee.negative = 0;
+      (void) powl (0.2, u.d);
+      x = powl (x, 1.5);
+      if (fabsl (x - 1e-30) > 1e-10) 
+	{
+	  printf ("powl (1e-20, 1.5): wrong result: %Lg\n", x);
+	  result = 1;
+	}
+    }
+# endif
+#endif
+
+  return result;
+}
diff --git a/sysdeps/x86_64/fpu/e_powl.S b/sysdeps/x86_64/fpu/e_powl.S
index 4959bea..f6a09c8 100644
--- a/sysdeps/x86_64/fpu/e_powl.S
+++ b/sysdeps/x86_64/fpu/e_powl.S
@@ -154,7 +154,7 @@ ENTRY(__ieee754_powl)
 	fucompp			// 1.0 : x : y
 	fnstsw
 	fxch			// x : 1.0 : y
-	test	$4500,%eax
+	test	$0x4500,%eax
 	jz	7f
 	fsub	%st(1)		// x-1 : 1.0 : y
 	fyl2xp1			// log2(x) : y

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