libm: sync with upstream FreeBSD.

Bug: http://b/143311272
Test: ran tests
Change-Id: I0fbf94fb5cd13e64a55957d0f951757746d0367a
diff --git a/libm/upstream-freebsd/lib/msun/src/e_exp.c b/libm/upstream-freebsd/lib/msun/src/e_exp.c
index 94c9769..dd88d3e 100644
--- a/libm/upstream-freebsd/lib/msun/src/e_exp.c
+++ b/libm/upstream-freebsd/lib/msun/src/e_exp.c
@@ -11,7 +11,7 @@
  */
 
 #include <sys/cdefs.h>
-__FBSDID("$FreeBSD$");
+__FBSDID("$FreeBSD: head/lib/msun/src/e_exp.c 352710 2019-09-25 18:50:57Z dim $");
 
 /* __ieee754_exp(x)
  * Returns the exponential of x.
@@ -145,9 +145,9 @@
     /* x is now in primary range */
 	t  = x*x;
 	if(k >= -1021)
-	    INSERT_WORDS(twopk,0x3ff00000+(k<<20), 0);
+	    INSERT_WORDS(twopk,((u_int32_t)(0x3ff+k))<<20, 0);
 	else
-	    INSERT_WORDS(twopk,0x3ff00000+((k+1000)<<20), 0);
+	    INSERT_WORDS(twopk,((u_int32_t)(0x3ff+(k+1000)))<<20, 0);
 	c  = x - t*(P1+t*(P2+t*(P3+t*(P4+t*P5))));
 	if(k==0) 	return one-((x*c)/(c-2.0)-x); 
 	else 		y = one-((lo-(x*c)/(2.0-c))-hi);