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-rw-r--r--REORG.TODO/sysdeps/i386/fpu/s_log1p.S67
1 files changed, 67 insertions, 0 deletions
diff --git a/REORG.TODO/sysdeps/i386/fpu/s_log1p.S b/REORG.TODO/sysdeps/i386/fpu/s_log1p.S
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index 0000000000..7978e76095
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+++ b/REORG.TODO/sysdeps/i386/fpu/s_log1p.S
@@ -0,0 +1,67 @@
+/*
+ * Written by J.T. Conklin <jtc@netbsd.org>.
+ * Public domain.
+ */
+
+#include <machine/asm.h>
+#include <i386-math-asm.h>
+
+RCSID("$NetBSD: s_log1p.S,v 1.7 1995/05/09 00:10:58 jtc Exp $")
+
+	.section .rodata
+
+	.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:	.double 0.29
+one:	.double 1.0
+
+DEFINE_DBL_MIN
+
+#ifdef PIC
+# define MO(op) op##@GOTOFF(%edx)
+#else
+# define MO(op) op
+#endif
+
+/*
+ * 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(__log1p)
+	fldln2
+
+	fldl	4(%esp)
+
+#ifdef	PIC
+	LOAD_PIC_REG (dx)
+#endif
+
+	fxam
+	fnstsw
+	fld	%st
+	sahf
+	jc	3f		// in case x is NaN or ħInf
+4:	fabs
+	fcompl	MO(limit)
+	fnstsw
+	sahf
+	jc	2f
+
+	faddl	MO(one)
+	fyl2x
+	ret
+
+2:	fyl2xp1
+	DBL_CHECK_FORCE_UFLOW_NONNAN
+	ret
+
+3:	jp	4b		// in case x is ħInf
+	fstp	%st(1)
+	fstp	%st(1)
+	ret
+
+END (__log1p)