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authorjoseph <joseph@7b3dc134-2b1b-0410-93df-9e9f96275f8d>2011-10-25 00:37:10 +0000
committerjoseph <joseph@7b3dc134-2b1b-0410-93df-9e9f96275f8d>2011-10-25 00:37:10 +0000
commit4bbe4e2185c5484328182720ff7b3bb4f9593bff (patch)
treecd67e40a74928c0f58d4f5b79d2e260e4099fee7 /libc/sysdeps/i386/i686/fpu/e_logl.S
parent91b4be71461f78cabe1fb5f164cea71b60e9e98a (diff)
downloadeglibc2-4bbe4e2185c5484328182720ff7b3bb4f9593bff.tar.gz
Merge changes between r15223 and r15532 from /fsf/trunk.
git-svn-id: svn://svn.eglibc.org/trunk@15545 7b3dc134-2b1b-0410-93df-9e9f96275f8d
Diffstat (limited to 'libc/sysdeps/i386/i686/fpu/e_logl.S')
-rw-r--r--libc/sysdeps/i386/i686/fpu/e_logl.S81
1 files changed, 81 insertions, 0 deletions
diff --git a/libc/sysdeps/i386/i686/fpu/e_logl.S b/libc/sysdeps/i386/i686/fpu/e_logl.S
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index 000000000..4e79a5a4b
--- /dev/null
+++ b/libc/sysdeps/i386/i686/fpu/e_logl.S
@@ -0,0 +1,81 @@
+/*
+ * Written by J.T. Conklin <jtc@netbsd.org>.
+ * Public domain.
+ *
+ * Adapted for `long double' by Ulrich Drepper <drepper@cygnus.com>.
+ * Changed to use fyl2xp1 for values near 1, <drepper@cygnus.com>.
+ * Adapted for i686 instructions.
+ */
+
+#include <machine/asm.h>
+
+#ifdef __ELF__
+ .section .rodata.cst8,"aM",@progbits,8
+#else
+ .text
+#endif
+ .p2align 3
+ ASM_TYPE_DIRECTIVE(one,@object)
+one: .double 1.0
+ ASM_SIZE_DIRECTIVE(one)
+ /* It is not important that this constant is precise. It is only
+ a value which is known to be on the safe side for using the
+ fyl2xp1 instruction. */
+ ASM_TYPE_DIRECTIVE(limit,@object)
+limit: .double 0.29
+ ASM_SIZE_DIRECTIVE(limit)
+
+
+#ifdef PIC
+# define MO(op) op##@GOTOFF(%edx)
+#else
+# define MO(op) op
+#endif
+
+ .text
+ENTRY(__ieee754_logl)
+ fldln2 // log(2)
+ fldt 4(%esp) // x : log(2)
+ fucomi %st
+ jp 3f
+#ifdef PIC
+ LOAD_PIC_REG (dx)
+#endif
+ fld %st // x : x : log(2)
+ fsubl MO(one) // x-1 : x : log(2)
+ fld %st // x-1 : x-1 : x : log(2)
+ fabs // |x-1| : x-1 : x : log(2)
+ fld MO(limit) // 0.29 : |x-1| : x-1 : x : log(2)
+ fcomip %st(1) // |x-1| : x-1 : x : log(2)
+ fstp %st(0) // x-1 : x : log(2)
+ jc 2f
+ fstp %st(1) // x-1 : log(2)
+ fyl2xp1 // log(x)
+ ret
+
+2: fstp %st(0) // x : log(2)
+ fyl2x // log(x)
+ ret
+
+3: fstp %st(1)
+ ret
+END (__ieee754_logl)
+
+ENTRY(__logl_finite)
+ fldln2 // log(2)
+ fldt 4(%esp) // x : log(2)
+#ifdef PIC
+ LOAD_PIC_REG (dx)
+#endif
+ fld %st // x : x : log(2)
+ fsubl MO(one) // x-1 : x : log(2)
+ fld %st // x-1 : x-1 : x : log(2)
+ fabs // |x-1| : x-1 : x : log(2)
+ fld MO(limit) // 0.29 : |x-1| : x-1 : x : log(2)
+ fcomip %st(1) // |x-1| : x-1 : x : log(2)
+ fstp %st(0) // x-1 : x : log(2)
+ jc 2b
+ fstp %st(1) // x-1 : log(2)
+ fyl2xp1 // log(x)
+ ret
+END(__logl_finite)