re PR middle-end/46761 (-fgraphite-identity produces wrong code for array initialization arr[i] = i)

	PR middle-end/46761
	* graphite-clast-to-gimple.c (graphite_create_new_loop_guard): Prefer
	to use unadjusted UB.

testsuite:
	* gcc.dg/graphite/pr46761.c: New.

From-SVN: r167980