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-rw-r--r--sysdeps/i386/fpu/e_log.S11
1 files changed, 10 insertions, 1 deletions
diff --git a/sysdeps/i386/fpu/e_log.S b/sysdeps/i386/fpu/e_log.S
index 5604e638f5..ce55b72292 100644
--- a/sysdeps/i386/fpu/e_log.S
+++ b/sysdeps/i386/fpu/e_log.S
@@ -36,11 +36,15 @@ limit:	.double 0.29
 ENTRY(__ieee754_log)
 	fldln2			// log(2)
 	fldl	4(%esp)		// x : log(2)
+	fxam
+	fnstsw
 #ifdef PIC
 	LOAD_PIC_REG (dx)
 #endif
 	fld	%st		// x : x : log(2)
-	fsubl	MO(one)		// x-1 : x : log(2)
+	sahf
+	jc	3f		// in case x is NaN or +-Inf
+4:	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)
@@ -54,4 +58,9 @@ ENTRY(__ieee754_log)
 2:	fstp	%st(0)		// x : log(2)
 	fyl2x			// log(x)
 	ret
+
+3:	jp	4b		// in case x is +-Inf
+	fstp	%st(1)
+	fstp	%st(1)
+	ret
 END (__ieee754_log)