re PR rtl-optimization/66076 (ICE: in vec_safe_grow, at vec.h:618 with -funroll-loops -mno-prefer-avx128 -march=bdver4)

gcc/
	PR rtl-optimization/66076
	* rtlanal.c (generic_subrtx_iterator <T>::add_single_to_queue):
	Don't grow the heap array if it is already big enough from a
	previous iteration.

gcc/testsuite/
	PR rtl-optimization/66076
	* gcc.dg/torture/pr66076.c: New test.

From-SVN: r222999