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-rw-r--r--sysdeps/i386/fpu/s_log1pf.S62
1 files changed, 62 insertions, 0 deletions
diff --git a/sysdeps/i386/fpu/s_log1pf.S b/sysdeps/i386/fpu/s_log1pf.S
new file mode 100644
index 0000000000..df9fdcbcfc
--- /dev/null
+++ b/sysdeps/i386/fpu/s_log1pf.S
@@ -0,0 +1,62 @@
+/*
+ * Written by J.T. Conklin <jtc@netbsd.org>.
+ * Public domain.
+ */
+
+#include <machine/asm.h>
+
+RCSID("$NetBSD: s_log1pf.S,v 1.4 1995/05/09 00:13:05 jtc Exp $")
+
+#ifdef __ELF__
+	.section .rodata
+#else
+	.text
+#endif
+	.align ALIGNARG(4)
+	/* The fyl2xp1 can only be used for values in
+		-1 + sqrt(2) / 2 <= x <= 1 - sqrt(2) / 2
+	   0.29 is a safe value.
+	*/
+limit:	.float 0.29
+one:	.float 1.0
+
+/*
+ * Use the fyl2xp1 function when the argument is in the range -0.29 to 0.29,
+ * otherwise fyl2x with the needed extra computation.
+ */
+	.text
+ENTRY(__log1pf)
+	fldln2
+
+	flds	4(%esp)
+
+#ifdef	PIC
+	call	1f
+1:	popl	%edx
+	addl	$_GLOBAL_OFFSET_TABLE_+[.-1b], %edx
+#endif
+
+	fld	%st
+	fabs
+#ifdef PIC
+	fcomps	limit@GOTOFF(%edx)
+#else
+	fcomps	limit
+#endif
+	fnstsw
+	sahf
+	jc	2f
+
+#ifdef PIC
+	fadds	one@GOTOFF(%edx)
+#else
+	fadds	one
+#endif
+	fyl2x
+	ret
+
+2:	fyl2xp1
+	ret
+
+END (__log1pf)
+weak_alias (__log1pf, log1pf)