Re: [patch] Tree level array prefetching (merge from killloop branch)

[Roger Sayle <roger at eyesopen dot com>]

On Mon, 16 Jan 2006, Zdenek Dvorak wrote:
> 	* doc/invoke.texi (-fprefetch-loop-arrays, -fprefetch-loop-arrays-rtl):
> 	Document.
> 	* tree-ssa-loop-niter.c (number_of_iterations_ne,
> 	number_of_iterations_lt, number_of_iterations_cond): Remember the shape
> 	of the ending condition.
> 	* tree-ssa-loop-manip.c: Include params.h.
> 	(build_if_stmt, can_unroll_loop_p, determine_exit_conditions,
> 	tree_unroll_loop): New functions.
> 	* tree-pass.h (pass_loop_prefetch): Declare.
> 	* loop.c (rest_of_handle_loop_optimize): Test for
> 	-fprefetch-loop-arrays-rtl.
> 	* tree-scalar-evolution.h (affine_iv): Moved to tree-flow.h.
> 	* timevar.def (TV_TREE_PREFETCH): New timevar.
> 	* tree-ssa-loop.c (tree_ssa_loop_prefetch, gate_tree_ssa_loop_prefetch,
> 	pass_loop_prefetch): New.
> 	* tree-cfgcleanup.c: Include tree-scalar-evolution.h.
> 	(cleanup_tree_cfg_loop): Call scev_reset.
> 	* common.opt (fprefetch-loop-arrays-rtl): Add.
> 	* tree-ssa-loop-prefetch.c: New file.
> 	* tree-outof-ssa.c (struct value_expr_d): Add expr_vars field.
> 	(new_temp_expr_table): Initialize expr_vars.
> 	(free_temp_expr_table): Cleanup expr_vars.
> 	(check_replaceable, find_replaceable_in_bb): Prevent accumulating
> 	expressions from being merged into one.
> 	* tree-flow.h (affine_iv): Moved from tree-scalar-evolution.h.
> 	(struct tree_niter_desc): Add control, bound and cmp fields.
> 	(tree_ssa_prefetch_arrays, can_unroll_loop_p, tree_unroll_loop):
> 	Declare.
> 	* Makefile.in (tree-ssa-loop-prefetch.o): Add.
> 	(tree-cfgcleanup.o): Add SCEV_H dependency.
> 	(tree-ssa-loop-manip.o): Add PARAMS_H dependency.
> 	* passes.c (init_optimization_passes): Add pass_loop_prefetch.

This is OK for mainline.

Hopefully, Canqun and the folks at the National University of
Defense Technology in China will resubmit their IA-64 prefetech
parameterization patches for use the new tree-level prefetcher.
They presented some impressive numbers last year, but unfortunately
their code was based upon the soon to be dead loop.c.

Thanks,

Roger
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