2017-11-03  Marc Glisse  <marc.glisse@inria.fr>

gcc/
	* match.pd (-(-A)): Rewrite.

gcc/testsuite/
	* gcc.dg/tree-ssa/negneg-1.c: New file.
	* gcc.dg/tree-ssa/negneg-2.c: Likewise.
	* gcc.dg/tree-ssa/negneg-3.c: Likewise.
	* gcc.dg/tree-ssa/negneg-4.c: Likewise.

From-SVN: r254382