re PR rtl-optimization/32283 (Missed induction variable optimization)
PR tree-optimization/32283 * tree-ssa-loop-ivopts.c (may_eliminate_iv): Use estimated_loop_iterations. (determine_use_iv_cost_condition): Decrease cost of expressions used in iv elimination. * gcc.dg/tree-ssa/loop-31.c: New test. From-SVN: r128272
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2007-09-08 Zdenek Dvorak <ook@ucw.cz>
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PR tree-optimization/32283
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* tree-ssa-loop-ivopts.c (may_eliminate_iv): Use
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estimated_loop_iterations.
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(determine_use_iv_cost_condition): Decrease cost of expressions
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used in iv elimination.
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2007-09-08 Richard Guenther <rguenther@suse.de>
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* tree-cfg.c (verify_gimple_expr): Avoid building new
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@ -1,3 +1,8 @@
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2007-09-08 Zdenek Dvorak <ook@ucw.cz>
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PR tree-optimization/32283
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* gcc.dg/tree-ssa/loop-31.c: New test.
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2007-09-08 Uros Bizjak <ubizjak@gmail.com>
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PR rtl-optimization/26449
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/* PR 32283 */
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/* { dg-do compile } */
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/* { dg-options "-O1 -fdump-tree-optimized" } */
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short a[(2048)];
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short foo (int len, int v)
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{
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int i;
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for (i = 0; i < len; i++) {
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a[i] = v;
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}
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return a[0];
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}
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/* When we do not have addressing mode including multiplication,
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the memory access should be strength-reduced. */
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/* { dg-final { scan-tree-dump-times " \\+ 2" 1 "optimized" { target arm-*-* ia64-*-* } } } */
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/* { dg-final { cleanup-tree-dump "optimized" } } */
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@ -3623,11 +3623,11 @@ may_eliminate_iv (struct ivopts_data *data,
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{
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basic_block ex_bb;
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edge exit;
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tree nit, nit_type;
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tree wider_type, period, per_type;
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tree nit, period;
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struct loop *loop = data->current_loop;
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aff_tree bnd;
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double_int period_value, max_niter;
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if (TREE_CODE (cand->iv->step) != INTEGER_CST)
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return false;
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@ -3650,25 +3650,19 @@ may_eliminate_iv (struct ivopts_data *data,
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if (!nit)
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return false;
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nit_type = TREE_TYPE (nit);
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/* Determine whether we may use the variable to test whether niter iterations
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elapsed. This is the case iff the period of the induction variable is
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greater than the number of iterations. */
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period = iv_period (cand->iv);
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if (!period)
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return false;
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per_type = TREE_TYPE (period);
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wider_type = TREE_TYPE (period);
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if (TYPE_PRECISION (nit_type) < TYPE_PRECISION (per_type))
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wider_type = per_type;
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else
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wider_type = nit_type;
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if (!integer_nonzerop (fold_build2 (GE_EXPR, boolean_type_node,
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fold_convert (wider_type, period),
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fold_convert (wider_type, nit))))
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/* Compare the period with the estimate on the number of iterations of the
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loop. */
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if (!estimated_loop_iterations (loop, true, &max_niter))
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return false;
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period_value = tree_to_double_int (period);
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if (double_int_ucmp (period_value, max_niter) <= 0)
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return false;
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cand_value_at (loop, cand, use->stmt, nit, &bnd);
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@ -3697,7 +3691,12 @@ determine_use_iv_cost_condition (struct ivopts_data *data,
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/* Try iv elimination. */
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if (may_eliminate_iv (data, use, cand, &bound))
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elim_cost = force_var_cost (data, bound, &depends_on_elim);
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{
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elim_cost = force_var_cost (data, bound, &depends_on_elim);
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/* The bound is a loop invariant, so it will be only computed
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once. */
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elim_cost /= AVG_LOOP_NITER (data->current_loop);
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}
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else
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elim_cost = INFTY;
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