passes.c (init_optimization_passes): Move veclower after SSA.

2010-11-04  Artjoms Sinkarovs <artyom.shinakroff@gmail.com>
	Richard Guenther  <rguenther@suse.de>

	* passes.c (init_optimization_passes): Move veclower after SSA.
	* tree-vect-generic.c (uniform_vector_p): New function.
	(expand_vector_operations_1): Handle conversion.
	(pass_lower_vector): Update SSA form.

	testsuite/
	* gcc.dg/vec-scal-opt.c: New testcase.
	* gcc.dg/vec-scal-opt1.c: New testcase.
	* gcc.dg/vec-scal-opt2.c: New testcase.

From-SVN: r166303

1 files changed, 90 insertions, 14 deletions

diff --git a/gcc/tree-vect-generic.c b/gcc/tree-vect-generic.c
index 1fd2962..3f58240 100644
--- a/gcc/tree-vect-generic.c
+++ b/gcc/tree-vect-generic.c
@@ -284,6 +284,55 @@ expand_vector_addition (gimple_stmt_iterator *gsi,
 				    a, b, code);
 }
 
+/* Check if vector VEC consists of all the equal elements and
+   that the number of elements corresponds to the type of VEC.
+   The function returns first element of the vector
+   or NULL_TREE if the vector is not uniform.  */
+static tree
+uniform_vector_p (tree vec)
+{
+  tree first, t, els;
+  unsigned i;
+
+  if (vec == NULL_TREE)
+    return NULL_TREE;
+
+  if (TREE_CODE (vec) == VECTOR_CST)
+    {
+      els = TREE_VECTOR_CST_ELTS (vec);
+      first = TREE_VALUE (els);
+      els = TREE_CHAIN (els);
+
+      for (t = els; t; t = TREE_CHAIN (t))
+	if (!operand_equal_p (first, TREE_VALUE (t), 0))
+	  return NULL_TREE;
+
+      return first;
+    }
+
+  else if (TREE_CODE (vec) == CONSTRUCTOR)
+    {
+      first = error_mark_node;
+
+      FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (vec), i, t)
+        {
+          if (i == 0)
+            {
+              first = t;
+              continue;
+            }
+	  if (!operand_equal_p (first, t, 0))
+	    return NULL_TREE;
+        }
+      if (i != TYPE_VECTOR_SUBPARTS (TREE_TYPE (vec)))
+	return NULL_TREE;
+      
+      return first;
+    }
+  
+  return NULL_TREE;
+}
+
 static tree
 expand_vector_operation (gimple_stmt_iterator *gsi, tree type, tree compute_type,
 			 gimple assign, enum tree_code code)
@@ -392,7 +441,7 @@ expand_vector_operations_1 (gimple_stmt_iterator *gsi)
   tree lhs, rhs1, rhs2 = NULL, type, compute_type;
   enum tree_code code;
   enum machine_mode compute_mode;
-  optab op;
+  optab op = NULL;
   enum gimple_rhs_class rhs_class;
   tree new_rhs;
 
@@ -434,18 +483,44 @@ expand_vector_operations_1 (gimple_stmt_iterator *gsi)
       || code == LROTATE_EXPR
       || code == RROTATE_EXPR)
     {
-      /* If the 2nd argument is vector, we need a vector/vector shift */
+      bool vector_scalar_shift;
+      op = optab_for_tree_code (code, type, optab_scalar);
+      
+      /* Vector/Scalar shift is supported.  */
+      vector_scalar_shift = (op && (optab_handler (op, TYPE_MODE (type)) 
+				    != CODE_FOR_nothing));
+
+      /* If the 2nd argument is vector, we need a vector/vector shift.
+         Except all the elements in the second vector are the same.  */
       if (VECTOR_MODE_P (TYPE_MODE (TREE_TYPE (rhs2))))
-	op = optab_for_tree_code (code, type, optab_vector);
-      else
-	{
-	  /* Try for a vector/scalar shift, and if we don't have one, see if we
-	     have a vector/vector shift */
-	  op = optab_for_tree_code (code, type, optab_scalar);
-	  if (!op
-	      || optab_handler (op, TYPE_MODE (type)) == CODE_FOR_nothing)
-	    op = optab_for_tree_code (code, type, optab_vector);
-	}
+        {
+          tree first;
+          gimple def_stmt;
+
+          /* Check whether we have vector <op> {x,x,x,x} where x
+             could be a scalar variable or a constant. Transform
+             vector <op> {x,x,x,x} ==> vector <op> scalar.  */
+          if (vector_scalar_shift 
+              && ((TREE_CODE (rhs2) == VECTOR_CST
+		   && (first = uniform_vector_p (rhs2)) != NULL_TREE)
+		  || (TREE_CODE (rhs2) == SSA_NAME 
+		      && (def_stmt = SSA_NAME_DEF_STMT (rhs2))
+		      && gimple_assign_single_p (def_stmt)
+		      && (first = uniform_vector_p
+			    (gimple_assign_rhs1 (def_stmt))) != NULL_TREE)))
+            {
+              gimple_assign_set_rhs2 (stmt, first);
+              update_stmt (stmt);
+              rhs2 = first;
+            }
+          else
+            op = optab_for_tree_code (code, type, optab_vector);
+        }
+    
+      /* Try for a vector/scalar shift, and if we don't have one, see if we
+         have a vector/vector shift */
+      else if (!vector_scalar_shift)
+        op = optab_for_tree_code (code, type, optab_vector);
     }
   else
     op = optab_for_tree_code (code, type, optab_default);
@@ -559,8 +634,9 @@ struct gimple_opt_pass pass_lower_vector =
   0,					/* properties_provided */
   0,					/* properties_destroyed */
   0,					/* todo_flags_start */
-  TODO_dump_func | TODO_ggc_collect
-    | TODO_verify_stmts			/* todo_flags_finish */
+  TODO_dump_func | TODO_update_ssa	/* todo_flags_finish */
+    | TODO_verify_ssa
+    | TODO_verify_stmts | TODO_verify_flow
  }
 };