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authorAdhemerval Zanella <azanella@linux.vnet.ibm.com>2012-04-11 16:30:13 -0300
committerAndreas Jaeger <aj@suse.de>2012-04-17 22:12:53 +0200
commit76da7265320010c7a273ed99f53938c0f32d5fad (patch)
treef094871a5f38652d2d320a11423fee602a8746e6 /sysdeps/i386/fpu
parent0396e69dbefb3630651d93e0a7526c4326a071bb (diff)
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Fix ilogb exception and errno (bug 6794)
[BZ #6794]
Following Joseph comments about bug 6794, here is a proposed fix. It turned out
to be a large fix mainly because I had to move some file along to follow libm
files/names conventions.

Basically I have added wrappers (w_ilogb.c, w_ilogbf.c, w_ilogbl.c) that now calls
the symbol '__ieee754_ilogb'. The wrappers checks for '__ieee754_ilogb' output and
set the errno and raise exceptions as expected.

The '__ieee754_ilogb' is implemented in sysdeps. I have moved the 's_ilogb[f|l]' files
to e_ilogb[f|l] and renamed the '__ilogb[f|l]' to '__ieee754_ilogb[f|l]'.

I also found out a bug in i386 and x86-64 assembly coded ilogb implementation where
it raises a FE_DIVBYZERO when argument is '0.0'. I corrected this issue as well.

Finally I added the errno and FE_INVALID tests for 0.0, NaN and +-InF argument. Tested
on i386, x86-64, ppc32 and ppc64.
Diffstat (limited to 'sysdeps/i386/fpu')
-rw-r--r--sysdeps/i386/fpu/e_ilogb.S (renamed from sysdeps/i386/fpu/s_ilogb.S)11
-rw-r--r--sysdeps/i386/fpu/e_ilogbf.S (renamed from sysdeps/i386/fpu/s_ilogbf.S)11
-rw-r--r--sysdeps/i386/fpu/e_ilogbl.S (renamed from sysdeps/i386/fpu/s_ilogbl.S)11
3 files changed, 24 insertions, 9 deletions
diff --git a/sysdeps/i386/fpu/s_ilogb.S b/sysdeps/i386/fpu/e_ilogb.S
index 0cf1ad7419..4fb635041f 100644
--- a/sysdeps/i386/fpu/s_ilogb.S
+++ b/sysdeps/i386/fpu/e_ilogb.S
@@ -7,7 +7,7 @@
 
 RCSID("$NetBSD: s_ilogb.S,v 1.5 1995/10/12 15:53:09 jtc Exp $")
 
-ENTRY(__ilogb)
+ENTRY(__ieee754_ilogb)
 	fldl	4(%esp)
 /* I added the following ugly construct because ilogb(+-Inf) is
    required to return INT_MAX in ISO C99.
@@ -18,6 +18,8 @@ ENTRY(__ilogb)
 	andb    %ah, %dh
 	cmpb    $0x05, %dh
 	je      1f		/* Is +-Inf, jump.  */
+	cmpb    $0x40, %dh
+	je      2f		/* Is +-0, jump.  */
 
 	fxtract
 	pushl	%eax
@@ -34,5 +36,8 @@ ENTRY(__ilogb)
 1:	fstp	%st
 	movl	$0x7fffffff, %eax
 	ret
-END (__ilogb)
-weak_alias (__ilogb, ilogb)
+2:	fstp	%st
+	movl	$0x80000000, %eax	/* FP_ILOGB0  */
+	ret
+END (__ieee754_ilogb)
+weak_alias (__ieee754_ilogb, __ilogb_finite)
diff --git a/sysdeps/i386/fpu/s_ilogbf.S b/sysdeps/i386/fpu/e_ilogbf.S
index 99e53edd75..fbb50be07f 100644
--- a/sysdeps/i386/fpu/s_ilogbf.S
+++ b/sysdeps/i386/fpu/e_ilogbf.S
@@ -7,7 +7,7 @@
 
 RCSID("$NetBSD: s_ilogbf.S,v 1.4 1995/10/22 20:32:43 pk Exp $")
 
-ENTRY(__ilogbf)
+ENTRY(__ieee754_ilogbf)
 	flds	4(%esp)
 /* I added the following ugly construct because ilogb(+-Inf) is
    required to return INT_MAX in ISO C99.
@@ -18,6 +18,8 @@ ENTRY(__ilogbf)
 	andb    %ah, %dh
 	cmpb    $0x05, %dh
 	je      1f		/* Is +-Inf, jump.  */
+	cmpb    $0x40, %dh
+	je      2f		/* Is +-0, jump.  */
 
 	fxtract
 	pushl	%eax
@@ -34,5 +36,8 @@ ENTRY(__ilogbf)
 1:	fstp	%st
 	movl	$0x7fffffff, %eax
 	ret
-END (__ilogbf)
-weak_alias (__ilogbf, ilogbf)
+2:	fstp	%st
+	movl	$0x80000000, %eax	/* FP_ILOGB0  */
+	ret
+END (__ieee754_ilogbf)
+weak_alias (__ieee754_ilogbf, __ilogbf_finite)
diff --git a/sysdeps/i386/fpu/s_ilogbl.S b/sysdeps/i386/fpu/e_ilogbl.S
index 1f559b311e..6e2be9a300 100644
--- a/sysdeps/i386/fpu/s_ilogbl.S
+++ b/sysdeps/i386/fpu/e_ilogbl.S
@@ -8,7 +8,7 @@
 
 RCSID("$NetBSD: $")
 
-ENTRY(__ilogbl)
+ENTRY(__ieee754_ilogbl)
 	fldt	4(%esp)
 /* I added the following ugly construct because ilogb(+-Inf) is
    required to return INT_MAX in ISO C99.
@@ -19,6 +19,8 @@ ENTRY(__ilogbl)
 	andb    %ah, %dh
 	cmpb    $0x05, %dh
 	je      1f		/* Is +-Inf, jump.  */
+	cmpb    $0x40, %dh
+	je      2f		/* Is +-0, jump.  */
 
 	fxtract
 	pushl	%eax
@@ -35,5 +37,8 @@ ENTRY(__ilogbl)
 1:	fstp	%st
 	movl	$0x7fffffff, %eax
 	ret
-END (__ilogbl)
-weak_alias (__ilogbl, ilogbl)
+2:	fstp	%st
+	movl	$0x80000000, %eax	/* FP_ILOGB0  */
+	ret
+END (__ieee754_ilogbl)
+weak_alias (__ieee754_ilogbl, __ilogbl_finite)