re PR rtl-optimization/17482 (GCSE after reload replacing changing instructions)

re PR rtl-optimization/17482 (GCSE after reload replacing changing instructions)

	PR rtl-optimization/17482
	* postreload-gcse.c (reg_avail_info, oprs_unchanged_p,
	load_killed_in_block_p): Clarify comments.
	(record_last_reg_set_info): Make static inline.
	(mark_call, mark_set, mark_clobber, mark_oprs_set): Remove.
	(record_opr_changes): New function to replace the above.
	(compute_hash_table): Clarify comments.  Use record_opr_changes.
	(reg_set_between_after_reload_p): Clean up.
	(reg_used_between_after_reload_p): Likewise.
	(eliminate_partially_redundant_load): Clarify comments.

From-SVN: r87794