backport: re PR tree-optimization/77916 (ICE in verify_gimple_in_cfg: invalid (pointe...

backport: re PR tree-optimization/77916 (ICE in verify_gimple_in_cfg: invalid (pointer) operands to plus/minus)

[gcc]

2016-10-23  Bill Schmidt  <wschmidt@linux.vnet.ibm.com>

	Backport from mainline
	2016-10-17  Bill Schmidt  <wschmidt@linux.vnet.ibm.com>

	PR tree-optimization/77916
	* gimple-ssa-strength-reduction.c (create_add_on_incoming_edge):
	Don't allow a MINUS_EXPR for pointer arithmetic for either known
	or unknown strides.
	(record_increment): Increments of -1 for unknown strides just use
	a multiply initializer like other negative values.
	(analyze_increments): Remove stopgap solution for -1 increment
	applied to pointer arithmetic.
	(insert_initializers): Requirement of initializer for -1 should be
	based on pointer-typedness of the candidate basis.

[gcc/testsuite]

2016-10-23  Bill Schmidt  <wschmidt@linux.vnet.ibm.com>

	Backport from mainline
	2016-10-17  Bill Schmidt  <wschmidt@linux.vnet.ibm.com>

	PR tree-optimization/77916
	* gcc.dg/torture/pr77916.c: New.

From-SVN: r241462