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diff --git a/sysdeps/libm-i387/s_exp2l.S b/sysdeps/libm-i387/s_exp2l.S
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+/*
+ * Written by J.T. Conklin <jtc@netbsd.org>.
+ * Adapted for exp2 by Ulrich Drepper <drepper@cygnus.com>.
+ * Public domain.
+ */
+
+#include <machine/asm.h>
+
+ENTRY(__exp2l)
+ fldt 4(%esp)
+/* I added the following ugly construct because exp(+-Inf) resulted
+ in NaN. The ugliness results from the bright minds at Intel.
+ For the i686 the code can be written better.
+ -- drepper@cygnus.com. */
+ fxam /* Is NaN or +-Inf? */
+ fstsw %ax
+ movb $0x45, %dh
+ andb %ah, %dh
+ cmpb $0x05, %dh
+ je 1f /* Is +-Inf, jump. */
+ fld %st
+ frndint /* int(x) */
+ fsubr %st,%st(1) /* fract(x) */
+ fxch
+ f2xm1 /* 2^(fract(x)) - 1 */
+ fld1
+ faddp /* 2^(fract(x)) */
+ fscale /* e^x */
+ fstp %st(1)
+ ret
+
+1: testl $0x200, %eax /* Test sign. */
+ jz 2f /* If positive, jump. */
+ fstp %st
+ fldz /* Set result to 0. */
+2: ret
+END (__exp2l)
+weak_alias (__exp2l, exp2l)