Re: [PATCH] Alias oracle for loop IM and store motion

[Zdenek Dvorak <rakdver at kam dot mff dot cuni dot cz>]

Hi,

> The ChangeLog for tree-ssa-loop-im.c is incomplete - Zdenek can
> you fill out the gap? ;)

Here it is; the bad news is that I no longer remember myself how
exactly does this (complete rewrite of store motion) work, so
fixing the bugs it causes will be fun :-)

> 	* tree-affine.h (aff_combination_expand): Declare.
> 	(get_inner_reference_aff): Likewise.
> 	* tree-affine.c (aff_combination_expand): Split out from
> 	tree_to_aff_combination_expand.
> 	(get_inner_reference_aff): New function.
> 	* Makefile.in (tree-ssa-loop-im.o): Add tree-affine.h and
> 	pointer-set.h dependencies.

	* tree-ssa-loop-im.c: Include tree-affine.h and pointer-set.h.
	(struct lim_aux_data): sm_done field removed.
	(mem_ref_loc_p, mem_ref_locs_p): New types.
	(struct mem_ref): Added id, stored, accesses_in_loop,
	indep_loop, dep_loop, indep_ref, dep_ref fields.
	Removed is_stored, locs and next fields.
	(memory_accesses): New variable.
	(movement_possibility): Do not allow moving statements
	that store to memory.
	(outermost_indep_loop, simple_mem_ref_in_stmt, mem_ref_in_stmt):
	New functions.
	(determine_max_movement): For statements with memory references,
	find the outermost loop in that the reference is independent.
	(move_computations_stmt): Mark the virtual operands for
	renaming.
	(memref_free, mem_ref_alloc, mem_ref_locs_alloc, mark_ref_stored,
	gather_mem_refs_stmt, gather_mem_refs_in_loops, vtoe_hash, vtoe_eq,
	vtoe_free, record_vop_access, get_vop_accesses, get_vop_stores,
	add_vop_ref_mapping, create_vop_ref_mapping_loop,
	create_vop_ref_mapping, analyze_memory_references,
	cannot_overlap_p, mem_refs_may_alias_p, rewrite_mem_ref_loc,
	get_all_locs_in_loop, ref_always_accessed_p,
	refs_independent_p, record_indep_loop, ref_indep_loop_p_1,
	ref_indep_loop_p, can_sm_ref_p, find_refs_for_sm,
	store_motion_loop, store_motion): New functions.
	(struct vop_to_refs_elt): New type.
	(record_mem_ref_loc, free_mem_ref_locs, rewrite_mem_refs,
	memref_hash, memref_eq, hoist_memory_references): Rewritten.
	(schedule_sm): Replaced by...
	(execute_sm): ... this.
	(determine_lsm_ref, hoist_memory_references,
	loop_suitable_for_sm, gather_mem_refs_stmt, gather_mem_refs,
	find_more_ref_vops, free_mem_ref, free_mem_refs,
	determine_lsm_loop, determine_lsm): Removed.
	(tree_ssa_lim_finalize): Free data structures used by store
	motion.
	(tree_ssa_lim): Call analyze_memory_references.  Use
	store_motion instead of determine_lsm.

Zdenek