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-rw-r--r--gcc/ChangeLog14
-rw-r--r--gcc/tree-ssa-loop-ivopts.c102
2 files changed, 79 insertions, 37 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index a049544..096c1d7 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,17 @@
+2005-04-23 Zdenek Dvorak <dvorakz@suse.cz>
+
+ * tree-ssa-loop-ivopts.c (struct cost_pair): Add value field.
+ (find_interesting_uses_cond): Do not use integer_zerop and
+ integer_nonzerop to check for integer constants.
+ (set_use_iv_cost): Record the value field.
+ (determine_use_iv_cost_generic, determine_use_iv_cost_address,
+ determine_use_iv_cost_outer): Set the value field of the cost pair.
+ (may_eliminate_iv): Do not return the comparison code.
+ (iv_elimination_compare): New function.
+ (determine_use_iv_cost_condition): Set the value field. Record
+ noneliminable invariants correctly.
+ (rewrite_use_compare, rewrite_use_outer): Use the value field.
+
2005-04-23 DJ Delorie <dj@redhat.com>
* diagnostic.c (warning): Accept parameter to classify warning option.
diff --git a/gcc/tree-ssa-loop-ivopts.c b/gcc/tree-ssa-loop-ivopts.c
index d9ffc65..00965bc 100644
--- a/gcc/tree-ssa-loop-ivopts.c
+++ b/gcc/tree-ssa-loop-ivopts.c
@@ -143,6 +143,9 @@ struct cost_pair
unsigned cost; /* The cost. */
bitmap depends_on; /* The list of invariants that have to be
preserved. */
+ tree value; /* For final value elimination, the expression for
+ the final value of the iv. For iv elimination,
+ the new bound to compare with. */
};
/* Use. */
@@ -1276,8 +1279,8 @@ find_interesting_uses_cond (struct ivopts_data *data, tree stmt, tree *cond_p)
const_iv.step = NULL_TREE;
- if (integer_zerop (*cond_p)
- || integer_nonzerop (*cond_p))
+ if (TREE_CODE (*cond_p) != SSA_NAME
+ && !COMPARISON_CLASS_P (*cond_p))
return;
if (TREE_CODE (*cond_p) == SSA_NAME)
@@ -2270,12 +2273,13 @@ alloc_use_cost_map (struct ivopts_data *data)
}
/* Sets cost of (USE, CANDIDATE) pair to COST and record that it depends
- on invariants DEPENDS_ON. */
+ on invariants DEPENDS_ON and that the value used in expressing it
+ is VALUE.*/
static void
set_use_iv_cost (struct ivopts_data *data,
struct iv_use *use, struct iv_cand *cand, unsigned cost,
- bitmap depends_on)
+ bitmap depends_on, tree value)
{
unsigned i, s;
@@ -2290,6 +2294,7 @@ set_use_iv_cost (struct ivopts_data *data,
use->cost_map[cand->id].cand = cand;
use->cost_map[cand->id].cost = cost;
use->cost_map[cand->id].depends_on = depends_on;
+ use->cost_map[cand->id].value = value;
return;
}
@@ -2308,6 +2313,7 @@ found:
use->cost_map[i].cand = cand;
use->cost_map[i].cost = cost;
use->cost_map[i].depends_on = depends_on;
+ use->cost_map[i].value = value;
}
/* Gets cost of (USE, CANDIDATE) pair. */
@@ -3307,12 +3313,12 @@ determine_use_iv_cost_generic (struct ivopts_data *data,
if (cand->pos == IP_ORIGINAL
&& cand->incremented_at == use->stmt)
{
- set_use_iv_cost (data, use, cand, 0, NULL);
+ set_use_iv_cost (data, use, cand, 0, NULL, NULL_TREE);
return true;
}
cost = get_computation_cost (data, use, cand, false, &depends_on);
- set_use_iv_cost (data, use, cand, cost, depends_on);
+ set_use_iv_cost (data, use, cand, cost, depends_on, NULL_TREE);
return cost != INFTY;
}
@@ -3326,7 +3332,7 @@ determine_use_iv_cost_address (struct ivopts_data *data,
bitmap depends_on;
unsigned cost = get_computation_cost (data, use, cand, true, &depends_on);
- set_use_iv_cost (data, use, cand, cost, depends_on);
+ set_use_iv_cost (data, use, cand, cost, depends_on, NULL_TREE);
return cost != INFTY;
}
@@ -3382,14 +3388,29 @@ iv_period (struct iv *iv)
return period;
}
+/* Returns the comparison operator used when eliminating the iv USE. */
+
+static enum tree_code
+iv_elimination_compare (struct ivopts_data *data, struct iv_use *use)
+{
+ struct loop *loop = data->current_loop;
+ basic_block ex_bb;
+ edge exit;
+
+ ex_bb = bb_for_stmt (use->stmt);
+ exit = EDGE_SUCC (ex_bb, 0);
+ if (flow_bb_inside_loop_p (loop, exit->dest))
+ exit = EDGE_SUCC (ex_bb, 1);
+
+ return (exit->flags & EDGE_TRUE_VALUE ? EQ_EXPR : NE_EXPR);
+}
+
/* Check whether it is possible to express the condition in USE by comparison
- of candidate CAND. If so, store the comparison code to COMPARE and the
- value compared with to BOUND. */
+ of candidate CAND. If so, store the value compared with to BOUND. */
static bool
may_eliminate_iv (struct ivopts_data *data,
- struct iv_use *use, struct iv_cand *cand,
- enum tree_code *compare, tree *bound)
+ struct iv_use *use, struct iv_cand *cand, tree *bound)
{
basic_block ex_bb;
edge exit;
@@ -3440,11 +3461,6 @@ may_eliminate_iv (struct ivopts_data *data,
fold_convert (wider_type, nit)))))
return false;
- if (exit->flags & EDGE_TRUE_VALUE)
- *compare = EQ_EXPR;
- else
- *compare = NE_EXPR;
-
*bound = cand_value_at (loop, cand, use->stmt, nit);
return true;
}
@@ -3455,37 +3471,46 @@ static bool
determine_use_iv_cost_condition (struct ivopts_data *data,
struct iv_use *use, struct iv_cand *cand)
{
- tree bound;
- enum tree_code compare;
+ tree bound = NULL_TREE, op, cond;
+ bitmap depends_on = NULL;
+ unsigned cost;
/* Only consider real candidates. */
if (!cand->iv)
{
- set_use_iv_cost (data, use, cand, INFTY, NULL);
+ set_use_iv_cost (data, use, cand, INFTY, NULL, NULL_TREE);
return false;
}
- if (may_eliminate_iv (data, use, cand, &compare, &bound))
+ if (may_eliminate_iv (data, use, cand, &bound))
{
- bitmap depends_on = NULL;
- unsigned cost = force_var_cost (data, bound, &depends_on);
+ cost = force_var_cost (data, bound, &depends_on);
- set_use_iv_cost (data, use, cand, cost, depends_on);
+ set_use_iv_cost (data, use, cand, cost, depends_on, bound);
return cost != INFTY;
}
/* The induction variable elimination failed; just express the original
giv. If it is compared with an invariant, note that we cannot get
rid of it. */
- if (TREE_CODE (*use->op_p) == SSA_NAME)
- record_invariant (data, *use->op_p, true);
- else
+ cost = get_computation_cost (data, use, cand, false, &depends_on);
+
+ cond = *use->op_p;
+ if (TREE_CODE (cond) != SSA_NAME)
{
- record_invariant (data, TREE_OPERAND (*use->op_p, 0), true);
- record_invariant (data, TREE_OPERAND (*use->op_p, 1), true);
+ op = TREE_OPERAND (cond, 0);
+ if (TREE_CODE (op) == SSA_NAME && !zero_p (get_iv (data, op)->step))
+ op = TREE_OPERAND (cond, 1);
+ if (TREE_CODE (op) == SSA_NAME)
+ {
+ op = get_iv (data, op)->base;
+ fd_ivopts_data = data;
+ walk_tree (&op, find_depends, &depends_on, NULL);
+ }
}
- return determine_use_iv_cost_generic (data, use, cand);
+ set_use_iv_cost (data, use, cand, cost, depends_on, NULL);
+ return cost != INFTY;
}
/* Checks whether it is possible to replace the final value of USE by
@@ -3525,7 +3550,7 @@ determine_use_iv_cost_outer (struct ivopts_data *data,
bitmap depends_on;
unsigned cost;
edge exit;
- tree value;
+ tree value = NULL_TREE;
struct loop *loop = data->current_loop;
/* The simple case first -- if we need to express value of the preserved
@@ -3535,7 +3560,7 @@ determine_use_iv_cost_outer (struct ivopts_data *data,
if (cand->pos == IP_ORIGINAL
&& cand->incremented_at == use->stmt)
{
- set_use_iv_cost (data, use, cand, 0, NULL);
+ set_use_iv_cost (data, use, cand, 0, NULL, NULL_TREE);
return true;
}
@@ -3543,7 +3568,7 @@ determine_use_iv_cost_outer (struct ivopts_data *data,
{
if (!may_replace_final_value (data, use, &value))
{
- set_use_iv_cost (data, use, cand, INFTY, NULL);
+ set_use_iv_cost (data, use, cand, INFTY, NULL, NULL_TREE);
return false;
}
@@ -3552,7 +3577,7 @@ determine_use_iv_cost_outer (struct ivopts_data *data,
cost /= AVG_LOOP_NITER (loop);
- set_use_iv_cost (data, use, cand, cost, depends_on);
+ set_use_iv_cost (data, use, cand, cost, depends_on, value);
return cost != INFTY;
}
@@ -3572,7 +3597,7 @@ determine_use_iv_cost_outer (struct ivopts_data *data,
cost = get_computation_cost (data, use, cand, false, &depends_on);
}
- set_use_iv_cost (data, use, cand, cost, depends_on);
+ set_use_iv_cost (data, use, cand, cost, depends_on, NULL_TREE);
return cost != INFTY;
}
@@ -4907,12 +4932,15 @@ rewrite_use_compare (struct ivopts_data *data,
tree *op_p, cond, op, stmts, bound;
block_stmt_iterator bsi = bsi_for_stmt (use->stmt);
enum tree_code compare;
+ struct cost_pair *cp = get_use_iv_cost (data, use, cand);
- if (may_eliminate_iv (data, use, cand, &compare, &bound))
+ bound = cp->value;
+ if (bound)
{
tree var = var_at_stmt (data->current_loop, cand, use->stmt);
tree var_type = TREE_TYPE (var);
+ compare = iv_elimination_compare (data, use);
bound = fold_convert (var_type, bound);
op = force_gimple_operand (unshare_expr (bound), &stmts,
true, NULL_TREE);
@@ -5087,8 +5115,8 @@ rewrite_use_outer (struct ivopts_data *data,
{
if (!cand->iv)
{
- bool ok = may_replace_final_value (data, use, &value);
- gcc_assert (ok);
+ struct cost_pair *cp = get_use_iv_cost (data, use, cand);
+ value = cp->value;
}
else
value = get_computation_at (data->current_loop,
generated by cgit v1.1 at 2025-05-06 16:35:02 +0000