re PR tree-optimization/52976 (Revision 186384 breaks the polyhedron tests aermod...

2012-04-16  Bill Schmidt  <wschmidt@linux.vnet.ibm.com>

	PR tree-optimization/52976
	* tree-ssa-reassoc.c (add_to_ops_vec_max_rank): New function.
	(undistribute_ops_list): Ops with repeat counts aren't eligible for
	undistribution.
	(attempt_builtin_powi): Call add_to_ops_vec_max_rank.

From-SVN: r186493

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index bb23d46..a1f2b4b 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,11 @@
+2012-04-16  Bill Schmidt  <wschmidt@linux.vnet.ibm.com>
+
+       PR tree-optimization/52976
+       * tree-ssa-reassoc.c (add_to_ops_vec_max_rank): New function.
+       (undistribute_ops_list): Ops with repeat counts aren't eligible for
+       undistribution.
+       (attempt_builtin_powi): Call add_to_ops_vec_max_rank.
+
 2012-04-16  Jan Hubicka  <jh@suse.cz>
 
        * cgraph.h (FOR_EACH_VARIABLE, FOR_EACH_VARIABLE, FOR_EACH_FUNCTION):

diff --git a/gcc/tree-ssa-reassoc.c b/gcc/tree-ssa-reassoc.c
index 4385fbf..854ce00 100644 (file)
--- a/gcc/tree-ssa-reassoc.c
+++ b/gcc/tree-ssa-reassoc.c
@@ -544,6 +544,28 @@ add_repeat_to_ops_vec (VEC(operand_entry_t, heap) **ops, tree op,
   reassociate_stats.pows_encountered++;
 }
 
+/* Add an operand entry to *OPS for the tree operand OP, giving the
+   new entry a larger rank than any other operand already in *OPS.  */
+
+static void
+add_to_ops_vec_max_rank (VEC(operand_entry_t, heap) **ops, tree op)
+{
+  operand_entry_t oe = (operand_entry_t) pool_alloc (operand_entry_pool);
+  operand_entry_t oe1;
+  unsigned i;
+  unsigned max_rank = 0;
+
+  FOR_EACH_VEC_ELT (operand_entry_t, *ops, i, oe1)
+    if (oe1->rank > max_rank)
+      max_rank = oe1->rank;
+
+  oe->op = op;
+  oe->rank = max_rank + 1;
+  oe->id = next_operand_entry_id++;
+  oe->count = 1;
+  VEC_safe_push (operand_entry_t, heap, *ops, oe);
+}
+
 /* Return true if STMT is reassociable operation containing a binary
    operation with tree code CODE, and is inside LOOP.  */
 
@@ -1200,6 +1222,7 @@ undistribute_ops_list (enum tree_code opcode,
       dcode = gimple_assign_rhs_code (oe1def);
       if ((dcode != MULT_EXPR
           && dcode != RDIV_EXPR)
+         || oe1->count != 1
          || !is_reassociable_op (oe1def, dcode, loop))
        continue;
 
@@ -1243,6 +1266,8 @@ undistribute_ops_list (enum tree_code opcode,
          oecount c;
          void **slot;
          size_t idx;
+         if (oe1->count != 1)
+           continue;
          c.oecode = oecode;
          c.cnt = 1;
          c.id = next_oecount_id++;
@@ -1311,7 +1336,7 @@ undistribute_ops_list (enum tree_code opcode,
 
          FOR_EACH_VEC_ELT (operand_entry_t, subops[i], j, oe1)
            {
-             if (oe1->op == c->op)
+             if (oe1->op == c->op && oe1->count == 1)
                {
                  SET_BIT (candidates2, i);
                  ++nr_candidates2;
@@ -3275,8 +3300,10 @@ attempt_builtin_powi (gimple stmt, VEC(operand_entry_t, heap) **ops,
          gsi_insert_before (&gsi, pow_stmt, GSI_SAME_STMT);
        }
 
-      /* Append the result of this iteration to the ops vector.  */
-      add_to_ops_vec (ops, iter_result);
+      /* Append the result of this iteration to the ops vector.
+         Give it a rank higher than all other ranks in the ops vector
+         so that all uses of it will be forced to come after it.  */
+      add_to_ops_vec_max_rank (ops, iter_result);
 
       /* Decrement the occurrence count of each element in the product
         by the count found above, and remove this many copies of each