re PR tree-optimization/38529 (ICE with nested loops)

	PR tree-optimization/38529
	* tree-vect-transform (vect_transform_stmt): Handle inner-loop stmts
	whose DEF is used in the loop-nest that is being vectorized, but
	outside the immediately enclosing loop.


Co-Authored-By: Ira Rosen <irar@il.ibm.com>

From-SVN: r142959

gcc/ChangeLog

+2008-12-30  Dorit Nuzman  <dorit@il.ibm.com>
+            Ira Rosen  <irar@il.ibm.com>
+
+	PR tree-optimization/38529
+	* tree-vect-transform (vect_transform_stmt): Handle inner-loop stmts
+	whose DEF is used in the loop-nest that is being vectorized, but
+	outside the immediately enclosing loop.
+
 2008-12-29  Seongbae Park  <seongbae.park@gmail.com>
 
 	* tree-profile.c (tree_init_ic_make_global_vars): Make static

gcc/testsuite/ChangeLog

+2008-12-29  Dorit Nuzman  <dorit@il.ibm.com>
+            Ira Rosen  <irar@il.ibm.com>
+
+	PR tree-optimization/38529
+	* gcc.dg/vect/pr38529.c: New test.
+
 2008-12-29  Jakub Jelinek  <jakub@redhat.com>
 
 	PR c++/38635

gcc/testsuite/gcc.dg/vect/pr38529.c

+/* { dg-do compile } */
+/* { dg-require-effective-target vect_float } */
+
+float a[4];
+
+void foo()
+{
+  int i, j;
+
+  for (i = 0; i < 4; ++i)
+    for (j = 0; j < 17; ++j)
+      a[i] = 0;
+}
+
+/* { dg-final { scan-tree-dump-times "OUTER LOOP VECTORIZED" 1 "vect"  } } */
+/* { dg-final { cleanup-tree-dump "vect" } } */
+
+

gcc/tree-vect-transform.c

@@ -7047,6 +7047,8 @@ vect_transform_stmt (gimple stmt, gimple_stmt_iterator *gsi,
   stmt_vec_info stmt_info = vinfo_for_stmt (stmt);
   gimple orig_stmt_in_pattern;
   bool done;
+  loop_vec_info loop_vinfo = STMT_VINFO_LOOP_VINFO (stmt_info);
+  struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo);
 
   switch (STMT_VINFO_TYPE (stmt_info))
     {
@@ -7130,6 +7132,43 @@ vect_transform_stmt (gimple stmt, gimple_stmt_iterator *gsi,
 	}
     }
 
+  /* Handle inner-loop stmts whose DEF is used in the loop-nest that
+     is being vectorized, but outside the immediately enclosing loop.  */
+  if (vec_stmt
+      && nested_in_vect_loop_p (loop, stmt)
+      && STMT_VINFO_TYPE (stmt_info) != reduc_vec_info_type
+      && (STMT_VINFO_RELEVANT (stmt_info) == vect_used_in_outer
+          || STMT_VINFO_RELEVANT (stmt_info) == vect_used_in_outer_by_reduction))
+    {
+      struct loop *innerloop = loop->inner;
+      imm_use_iterator imm_iter;
+      use_operand_p use_p;
+      tree scalar_dest;
+      gimple exit_phi;
+
+      if (vect_print_dump_info (REPORT_DETAILS))
+       fprintf (vect_dump, "Record the vdef for outer-loop vectorization.");
+
+      /* Find the relevant loop-exit phi-node, and reord the vec_stmt there
+        (to be used when vectorizing outer-loop stmts that use the DEF of
+        STMT).  */
+      if (gimple_code (stmt) == GIMPLE_PHI)
+        scalar_dest = PHI_RESULT (stmt);
+      else
+        scalar_dest = gimple_assign_lhs (stmt);
+
+      FOR_EACH_IMM_USE_FAST (use_p, imm_iter, scalar_dest)
+       {
+         if (!flow_bb_inside_loop_p (innerloop, gimple_bb (USE_STMT (use_p))))
+           {
+             exit_phi = USE_STMT (use_p);
+             STMT_VINFO_VEC_STMT (vinfo_for_stmt (exit_phi)) = vec_stmt;
+           }
+       }
+    }
+
+  /* Handle stmts whose DEF is used outside the loop-nest that is
+     being vectorized.  */
   if (STMT_VINFO_LIVE_P (stmt_info)
       && STMT_VINFO_TYPE (stmt_info) != reduc_vec_info_type)
     {