add hash_map class

add hash_map class

gcc/

	* alloc-pool.c (alloc_pool_hash): Use hash_map instead of hash_table.
	* dominance.c (iterate_fix_dominators): Use hash_map instead of
	pointer_map.
	* hash-map.h: New file.
	* ipa-comdats.c: Use hash_map instead of pointer_map.
	* ipa.c: Likewise.
	* lto-section-out.c: Adjust.
	* lto-streamer.h: Replace pointer_map with hash_map.
	* symtab.c (verify_symtab): Likewise.
	* tree-ssa-strlen.c (decl_to_stridxlist_htab): Likewise.
	* tree-ssa-uncprop.c (val_ssa_equiv): Likewise.
	* tree-streamer.h: Likewise.
	* tree-streamer.c: Adjust.
	* pointer-set.h: Remove pointer_map.

gcc/lto/

	* lto.c (canonical_type_hash_cache): Use hash_map instead of
	pointer_map.

From-SVN: r211938