math-emu: Use statement expressions to fix Wshift-count-overflow warning

To avoid "shift count >= width of type" warning, using statement
expressions to implement the conditional controlling before constant shift

The modification in op-2.h is taken from the glibc
commit 'sysdeps/unix/sysv/lin ("fe0b1e854ad32")'.

Signed-off-by: Vincent Chen <[e-mail]>
Acked-by: Greentime Hu <[e-mail]>
Signed-off-by: Greentime Hu <[e-mail]>

include/math-emu/op-2.h

···
  */
 
 #define _FP_FRAC_ASSEMBLE_2(r, X, rsize)	\
-  do {						\
-    if (rsize <= _FP_W_TYPE_SIZE)		\
-      r = X##_f0;				\
-    else					\
-      {						\
-	r = X##_f1;				\
-	r <<= _FP_W_TYPE_SIZE;			\
-	r += X##_f0;				\
-      }						\
-  } while (0)
+	(void) (((rsize) <= _FP_W_TYPE_SIZE)	\
+		? ({ (r) = X##_f0; })		\
+		: ({				\
+		     (r) = X##_f1;		\
+		     (r) <<= _FP_W_TYPE_SIZE;	\
+		     (r) += X##_f0;		\
+		    }))
 
 #define _FP_FRAC_DISASSEMBLE_2(X, r, rsize)				\
   do {									\

include/math-emu/op-common.h

···
 	  ur_ = (unsigned rtype) -r;					\
 	else								\
 	  ur_ = (unsigned rtype) r;					\
-	if (rsize <= _FP_W_TYPE_SIZE)					\
-	  __FP_CLZ(X##_e, ur_);						\
-	else								\
-	  __FP_CLZ_2(X##_e, (_FP_W_TYPE)(ur_ >> _FP_W_TYPE_SIZE), 	\
-		     (_FP_W_TYPE)ur_);					\
+	(void) (((rsize) <= _FP_W_TYPE_SIZE)				\
+		? ({ __FP_CLZ(X##_e, ur_); })				\
+		: ({							\
+		     __FP_CLZ_2(X##_e, (_FP_W_TYPE)(ur_ >> _FP_W_TYPE_SIZE),  \
+							    (_FP_W_TYPE)ur_); \
+		  }));							\
 	if (rsize < _FP_W_TYPE_SIZE)					\
 		X##_e -= (_FP_W_TYPE_SIZE - rsize);			\
 	X##_e = rsize - X##_e - 1;					\