invoke.texi (-fprefetch-loop-arrays, [...]): Document.

	* 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.

From-SVN: r110964

1 files changed, 25 insertions, 0 deletions

diff --git a/gcc/tree-flow.h b/gcc/tree-flow.h
index 0e4824e..7774c3b 100644
--- a/gcc/tree-flow.h
+++ b/gcc/tree-flow.h
@@ -667,6 +667,17 @@ extern void replace_exp (use_operand_p, tree);
 extern bool may_propagate_copy (tree, tree);
 extern bool may_propagate_copy_into_asm (tree);
 
+/* Affine iv.  */
+
+typedef struct
+{
+  /* Iv = BASE + STEP * i.  */
+  tree base, step;
+
+  /* True if this iv does not overflow.  */
+  bool no_overflow;
+} affine_iv;
+
 /* Description of number of iterations of a loop.  All the expressions inside
    the structure can be evaluated at the end of the loop's preheader
    (and due to ssa form, also anywhere inside the body of the loop).  */
@@ -697,6 +708,15 @@ struct tree_niter_desc
 			   MAX_SIGNED_INT.  However if the (n <= 0) assumption
 			   is eliminated (by looking at the guard on entry of
 			   the loop), then the information would be lost.  */
+
+  /* The simplified shape of the exit condition.  The loop exits if
+     CONTROL CMP BOUND is false, where CMP is one of NE_EXPR,
+     LT_EXPR, or GT_EXPR, and step of CONTROL is positive if CMP is
+     LE_EXPR and negative if CMP is GE_EXPR.  This information is used
+     by loop unrolling.  */
+  affine_iv control;
+  tree bound;
+  enum tree_code cmp;
 };
 
 /* In tree-vectorizer.c */
@@ -711,6 +731,7 @@ void tree_ssa_lim (struct loops *);
 void tree_ssa_unswitch_loops (struct loops *);
 void canonicalize_induction_variables (struct loops *);
 void tree_unroll_loops_completely (struct loops *, bool);
+void tree_ssa_prefetch_arrays (struct loops *);
 void remove_empty_loops (struct loops *);
 void tree_ssa_iv_optimize (struct loops *);
 
@@ -748,6 +769,10 @@ struct loop *tree_ssa_loop_version (struct loops *, struct loop *, tree,
 tree expand_simple_operations (tree);
 void substitute_in_loop_info (struct loop *, tree, tree);
 edge single_dom_exit (struct loop *);
+bool can_unroll_loop_p (struct loop *loop, unsigned factor,
+			struct tree_niter_desc *niter);
+void tree_unroll_loop (struct loops *, struct loop *, unsigned,
+		       edge, struct tree_niter_desc *);
 
 /* In tree-ssa-threadedge.c */
 extern bool potentially_threadable_block (basic_block);