re PR middle-end/38250 (ICE with -O2 -ftree-loop-distribution)

        PR middle-end/38250
        * tree-loop-distribution.c (build_size_arg): New function.
        (generate_memset_zero): Checks if DR_STEP(de) is NULL.
        Reorganized generating of stmts.
        * testsuite/gcc.dg/tree-ssa/pr38250.c: New file.
        * tree-data-ref.c (dr_analyze_innermost): Returns bool.
        Indicate if analysis succeed.
        * tree-data-ref.h (dr_analyze_innermost): Returns bool.
        * tree-predcom.c (valid_initializer_p, find_looparound_phi):
        Uses new definition of dr_analyze_innermost.

From-SVN: r142394

gcc/ChangeLog

+2008-12-03  Tomas Bily  <tbily@suse.cz>
+
+        PR middle-end/38250
+        * tree-loop-distribution.c (build_size_arg): New function.
+        (generate_memset_zero): Checks if dr_analyze_innermost succeed.
+        Reorganized generating of stmts.
+        * testsuite/gcc.dg/tree-ssa/pr38250.c: New file.
+        * tree-data-ref.c (dr_analyze_innermost): Returns bool.
+        Indicate if analysis succeed.
+        * tree-data-ref.h (dr_analyze_innermost): Returns bool.
+        * tree-predcom.c (valid_initializer_p, find_looparound_phi):
+        Uses new definition of dr_analyze_innermost.
+
 2008-12-03  Ben Elliston  <bje@au.ibm.com>
 
 	* tree-ssa-pre.c (do_regular_insertion): Initialise edoubleprime.

gcc/tree-data-ref.c

@@ -667,9 +667,9 @@ canonicalize_base_object_address (tree addr)
 }
 
 /* Analyzes the behavior of the memory reference DR in the innermost loop that
-   contains it.  */
+   contains it. Returns true if analysis succeed or false otherwise.  */
 
-void
+bool
 dr_analyze_innermost (struct data_reference *dr)
 {
   gimple stmt = DR_STMT (dr);
@@ -693,7 +693,7 @@ dr_analyze_innermost (struct data_reference *dr)
     {
       if (dump_file && (dump_flags & TDF_DETAILS))
 	fprintf (dump_file, "failed: bit offset alignment.\n");
-      return;
+      return false;
     }
 
   base = build_fold_addr_expr (base);
@@ -701,7 +701,7 @@ dr_analyze_innermost (struct data_reference *dr)
     {
       if (dump_file && (dump_flags & TDF_DETAILS))
 	fprintf (dump_file, "failed: evolution of base is not affine.\n");
-      return;
+      return false;
     }
   if (!poffset)
     {
@@ -712,7 +712,7 @@ dr_analyze_innermost (struct data_reference *dr)
     {
       if (dump_file && (dump_flags & TDF_DETAILS))
 	fprintf (dump_file, "failed: evolution of offset is not affine.\n");
-      return;
+      return false;
     }
 
   init = ssize_int (pbitpos / BITS_PER_UNIT);
@@ -735,6 +735,8 @@ dr_analyze_innermost (struct data_reference *dr)
 
   if (dump_file && (dump_flags & TDF_DETAILS))
     fprintf (dump_file, "success.\n");
+
+  return true;
 }
 
 /* Determines the base object and the list of indices of memory reference

gcc/tree-data-ref.h

@@ -381,7 +381,7 @@ DEF_VEC_O (data_ref_loc);
 DEF_VEC_ALLOC_O (data_ref_loc, heap);
 
 bool get_references_in_stmt (gimple, VEC (data_ref_loc, heap) **);
-void dr_analyze_innermost (struct data_reference *);
+bool dr_analyze_innermost (struct data_reference *);
 extern bool compute_data_dependences_for_loop (struct loop *, bool,
 					       VEC (data_reference_p, heap) **,
 					       VEC (ddr_p, heap) **);

gcc/tree-loop-distribution.c

@@ -216,13 +216,30 @@ generate_loops_for_partition (struct loop *loop, bitmap partition, bool copy_p)
   return true;
 }
 
+/* Build size argument.  */
+
+static inline tree
+build_size_arg (tree nb_iter, tree op, gimple_seq* stmt_list)
+{
+    tree nb_bytes;
+    gimple_seq stmts = NULL;
+
+    nb_bytes = fold_build2 (MULT_EXPR, TREE_TYPE (nb_iter),
+			    nb_iter, TYPE_SIZE_UNIT (TREE_TYPE (op)));
+    nb_bytes = force_gimple_operand (nb_bytes, &stmts, true, NULL);
+    gimple_seq_add_seq (stmt_list, stmts);
+
+    return nb_bytes;
+}
+
 /* Generate a call to memset.  Return true when the operation succeeded.  */
 
 static bool
 generate_memset_zero (gimple stmt, tree op0, tree nb_iter,
 		      gimple_stmt_iterator bsi)
 {
-  tree t, nb_bytes, addr_base;
+  tree t, addr_base;
+  tree nb_bytes = NULL;
   bool res = false;
   gimple_seq stmts = NULL, stmt_list = NULL;
   gimple fn_call;
@@ -231,14 +248,10 @@ generate_memset_zero (gimple stmt, tree op0, tree nb_iter,
   ssa_op_iter iter;
   struct data_reference *dr = XCNEW (struct data_reference);
 
-  nb_bytes = fold_build2 (MULT_EXPR, TREE_TYPE (nb_iter),
-			  nb_iter, TYPE_SIZE_UNIT (TREE_TYPE (op0)));
-  nb_bytes = force_gimple_operand (nb_bytes, &stmts, true, NULL);
-  gimple_seq_add_seq (&stmt_list, stmts);
-
   DR_STMT (dr) = stmt;
   DR_REF (dr) = op0;
-  dr_analyze_innermost (dr);
+  if (!dr_analyze_innermost (dr))
+    goto end;
 
   /* Test for a positive stride, iterating over every element.  */
   if (integer_zerop (fold_build2 (MINUS_EXPR, integer_type_node, DR_STEP (dr),
@@ -253,6 +266,7 @@ generate_memset_zero (gimple stmt, tree op0, tree nb_iter,
 				       TYPE_SIZE_UNIT (TREE_TYPE (op0)),
 				       DR_STEP (dr))))
     {
+      nb_bytes = build_size_arg (nb_iter, op0, &stmt_list);
       addr_base = size_binop (PLUS_EXPR, DR_OFFSET (dr), DR_INIT (dr));
       addr_base = fold_build2 (MINUS_EXPR, sizetype, addr_base, nb_bytes);
       addr_base = force_gimple_operand (addr_base, &stmts, true, NULL);
@@ -272,6 +286,8 @@ generate_memset_zero (gimple stmt, tree op0, tree nb_iter,
   fntype = TREE_TYPE (fndecl);
   fn = build1 (ADDR_EXPR, build_pointer_type (fntype), fndecl);
 
+  if (!nb_bytes)
+      nb_bytes = build_size_arg (nb_iter, op0, &stmt_list);
   fn_call = gimple_build_call (fn, 3, mem, integer_zero_node, nb_bytes);
   gimple_seq_add_stmt (&stmt_list, fn_call);
 

gcc/tree-predcom.c

@@ -1026,9 +1026,6 @@ valid_initializer_p (struct data_reference *ref,
   aff_tree diff, base, step;
   double_int off;
 
-  if (!DR_BASE_ADDRESS (ref))
-    return false;
-
   /* Both REF and ROOT must be accessing the same object.  */
   if (!operand_equal_p (DR_BASE_ADDRESS (ref), DR_BASE_ADDRESS (root), 0))
     return false;
@@ -1115,7 +1112,8 @@ find_looparound_phi (struct loop *loop, dref ref, dref root)
   memset (&init_dr, 0, sizeof (struct data_reference));
   DR_REF (&init_dr) = init_ref;
   DR_STMT (&init_dr) = phi;
-  dr_analyze_innermost (&init_dr);
+  if (!dr_analyze_innermost (&init_dr))
+    return NULL;
 
   if (!valid_initializer_p (&init_dr, ref->distance + 1, root->ref))
     return NULL;