* fold-const.c (fold) [NOP_EXPR]: Convert (T)(x&c) into ((T)x&(T)c)
	for integer constant c (if x has unsigned type or sign bit is not
	set in c).  This folds the zero/sign extension into the bit-wise and
	operation.

	* gcc.c-torture/compile/20020415-1.c: New.

Co-Authored-By: Jakub Jelinek <jakub@redhat.com>

From-SVN: r52465