* Makefile.in (local-alloc.o): Depend on $(GGC_H) and reload.h.
	* local-alloc.c: Include "ggc.h" and "reload.h".
	(struct equivalence): New member is_arg_equivalence.
	(local_alloc): Always call update_equiv_regs.
	(update_equiv_regs): Allocate reg_equiv_init; set reg_equiv_init_size.
	Detect equivalences made by stores to memory in a second pass.
	Return early if not optimizing.
	Initialize reg_equiv_init for all equivalences; treat equivalences for
	REG_EQUIV notes existing before this pass specially.
	(no_equiv): Don't clear reg_equiv_init or remove notes if the
	is_arg_equivalence field is set.
	* reload.h (reg_equiv_init, reg_equiv_init_size): Declare.
	* reload1.c (reg_equiv_init): No longer static.
	(reg_equiv_init_size): New variable.
	(reload): Don't allocate reg_equiv_init; don't free it when done but
	clear it.
	Restructure equivalence set up code not to set reg_equiv_init, but to
	clear it when we can't use an equivalence.
	Undo change disabling equivalences for MEM_READONLY_P memrefs.
	Dump equivalencing insns to dump_file.

From-SVN: r100975