2017-09-28  Joseph Myers  <joseph@codesourcery.com>

	[BZ #22225]
	* sysdeps/ieee754/dbl-64/s_nearbyint.c (__nearbyint): Use
	math_opt_barrier on argument when doing arithmetic on it.
	* sysdeps/ieee754/dbl-64/wordsize-64/s_nearbyint.c (__nearbyint):
	Likewise.  Use math_force_eval not math_opt_barrier after
	arithmetic.
	* sysdeps/ieee754/flt-32/s_nearbyintf.c (__nearbyintf): Use
	math_opt_barrier on argument when doing arithmetic on it.
	* sysdeps/ieee754/ldbl-128/s_nearbyintl.c (__nearbyintl):
	Likewise.

Index: glibc-2.26/sysdeps/ieee754/dbl-64/s_nearbyint.c
===================================================================
--- glibc-2.26.orig/sysdeps/ieee754/dbl-64/s_nearbyint.c
+++ glibc-2.26/sysdeps/ieee754/dbl-64/s_nearbyint.c
@@ -48,7 +48,7 @@ __nearbyint (double x)
       if (j0 < 0)
 	{
 	  libc_feholdexcept (&env);
-	  w = TWO52[sx] + x;
+	  w = TWO52[sx] + math_opt_barrier (x);
 	  t = w - TWO52[sx];
 	  math_force_eval (t);
 	  libc_fesetenv (&env);
@@ -65,7 +65,7 @@ __nearbyint (double x)
 	return x;                       /* x is integral */
     }
   libc_feholdexcept (&env);
-  w = TWO52[sx] + x;
+  w = TWO52[sx] + math_opt_barrier (x);
   t = w - TWO52[sx];
   math_force_eval (t);
   libc_fesetenv (&env);
Index: glibc-2.26/sysdeps/ieee754/dbl-64/wordsize-64/s_nearbyint.c
===================================================================
--- glibc-2.26.orig/sysdeps/ieee754/dbl-64/wordsize-64/s_nearbyint.c
+++ glibc-2.26/sysdeps/ieee754/dbl-64/wordsize-64/s_nearbyint.c
@@ -42,9 +42,9 @@ __nearbyint(double x)
 	if(__builtin_expect(j0<52, 1)) {
 	    if(j0<0) {
 		libc_feholdexcept (&env);
-		double w = TWO52[sx]+x;
+		double w = TWO52[sx] + math_opt_barrier (x);
 		double t =  w-TWO52[sx];
-		math_opt_barrier(t);
+		math_force_eval (t);
 		libc_fesetenv (&env);
 		return __copysign (t, x);
 	    }
@@ -53,9 +53,9 @@ __nearbyint(double x)
 	    else return x;		/* x is integral */
 	}
 	libc_feholdexcept (&env);
-	double w = TWO52[sx]+x;
+	double w = TWO52[sx] + math_opt_barrier (x);
 	double t = w-TWO52[sx];
-	math_opt_barrier (t);
+	math_force_eval (t);
 	libc_fesetenv (&env);
 	return t;
 }
Index: glibc-2.26/sysdeps/ieee754/flt-32/s_nearbyintf.c
===================================================================
--- glibc-2.26.orig/sysdeps/ieee754/flt-32/s_nearbyintf.c
+++ glibc-2.26/sysdeps/ieee754/flt-32/s_nearbyintf.c
@@ -37,7 +37,7 @@ __nearbyintf(float x)
 	if(j0<23) {
 	    if(j0<0) {
 		libc_feholdexceptf (&env);
-		w = TWO23[sx]+x;
+		w = TWO23[sx] + math_opt_barrier (x);
 		t =  w-TWO23[sx];
 		math_force_eval (t);
 		libc_fesetenvf (&env);
@@ -50,7 +50,7 @@ __nearbyintf(float x)
 	    else return x;		/* x is integral */
 	}
 	libc_feholdexceptf (&env);
-	w = TWO23[sx]+x;
+	w = TWO23[sx] + math_opt_barrier (x);
 	t = w-TWO23[sx];
 	math_force_eval (t);
 	libc_fesetenvf (&env);
Index: glibc-2.26/sysdeps/ieee754/ldbl-128/s_nearbyintl.c
===================================================================
--- glibc-2.26.orig/sysdeps/ieee754/ldbl-128/s_nearbyintl.c
+++ glibc-2.26/sysdeps/ieee754/ldbl-128/s_nearbyintl.c
@@ -45,7 +45,7 @@ _Float128 __nearbyintl(_Float128 x)
 	if(j0<112) {
 	    if(j0<0) {
 		feholdexcept (&env);
-	        w = TWO112[sx]+x;
+	        w = TWO112[sx] + math_opt_barrier (x);
 	        t = w-TWO112[sx];
 		math_force_eval (t);
 	        fesetenv (&env);
@@ -58,7 +58,7 @@ _Float128 __nearbyintl(_Float128 x)
 	    else return x;		/* x is integral */
 	}
 	feholdexcept (&env);
-	w = TWO112[sx]+x;
+	w = TWO112[sx] + math_opt_barrier (x);
 	t = w-TWO112[sx];
 	math_force_eval (t);
 	fesetenv (&env);