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+/*
+ * Written by J.T. Conklin <jtc@netbsd.org>.
+ * Public domain.
+ *
+ * Adapted for `long double' by Ulrich Drepper <drepper@cygnus.com>.
+ * Adapted for x86-64 by Andreas Jaeger <aj@suse.de>.
+ */
+
+#include <machine/asm.h>
+
+RCSID("$NetBSD: $")
+
+
+#ifdef __ELF__
+ .section .rodata
+#else
+ .text
+#endif
+ .align ALIGNARG(4)
+ 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##(%rip)
+#else
+#define MO(op) op
+#endif
+
+ .text
+ENTRY(__ieee754_logl)
+ fldln2 // log(2)
+ fldt 8(%rsp) // x : log(2)
+ 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)
+ fcompl MO(limit) // x-1 : x : log(2)
+ fnstsw // x-1 : x : log(2)
+ andb $0x45, %ah
+ jz 2f
+ fstp %st(1) // x-1 : log(2)
+ fyl2xp1 // log(x)
+ ret
+
+2: fstp %st(0) // x : log(2)
+ fyl2x // log(x)
+ ret
+END (__ieee754_logl)