PR tree-optimization/27549

[pf3gnuchains/gcc-fork.git] / gcc / tree-stdarg.c

diff --git a/gcc/tree-stdarg.c b/gcc/tree-stdarg.c
index a744658..4a67bc8 100644 (file)
--- a/gcc/tree-stdarg.c
+++ b/gcc/tree-stdarg.c
@@ -59,7 +59,7 @@ reachable_at_most_once (basic_block va_arg_bb, basic_block va_start_bb)
   if (! dominated_by_p (CDI_DOMINATORS, va_arg_bb, va_start_bb))
     return false;
 
-  stack = xmalloc ((n_basic_blocks + 1) * sizeof (edge));
+  stack = XNEWVEC (edge, n_basic_blocks + 1);
   sp = 0;
 
   visited = sbitmap_alloc (last_basic_block);
@@ -125,7 +125,7 @@ va_list_counter_bump (struct stdarg_info *si, tree counter, tree rhs,
     {
       unsigned int i;
 
-      si->offsets = xmalloc (num_ssa_names * sizeof (int));
+      si->offsets = XNEWVEC (int, num_ssa_names);
       for (i = 0; i < num_ssa_names; ++i)
        si->offsets[i] = -1;
     }
@@ -603,7 +603,7 @@ gate_optimize_stdarg (void)
 
 /* Entry point to the stdarg optimization pass.  */
 
-static void
+static unsigned int
 execute_optimize_stdarg (void)
 {
   basic_block bb;
@@ -624,6 +624,7 @@ execute_optimize_stdarg (void)
   va_list_simple_ptr = POINTER_TYPE_P (va_list_type_node)
                       && (TREE_TYPE (va_list_type_node) == void_type_node
                           || TREE_TYPE (va_list_type_node) == char_type_node);
+  gcc_assert (is_gimple_reg_type (va_list_type_node) == va_list_simple_ptr);
 
   FOR_EACH_BB (bb)
     {
@@ -734,12 +735,58 @@ execute_optimize_stdarg (void)
   if (va_list_simple_ptr)
     cfun->va_list_fpr_size = VA_LIST_MAX_FPR_SIZE;
 
+  calculate_dominance_info (CDI_DOMINATORS);
+
   FOR_EACH_BB (bb)
     {
       block_stmt_iterator i;
 
       si.compute_sizes = -1;
       si.bb = bb;
+
+      /* For va_list_simple_ptr, we have to check PHI nodes too.  We treat
+        them as assignments for the purpose of escape analysis.  This is
+        not needed for non-simple va_list because virtual phis don't perform
+        any real data movement.  */
+      if (va_list_simple_ptr)
+       {
+         tree phi, lhs, rhs;
+         use_operand_p uop;
+         ssa_op_iter soi;
+
+         for (phi = phi_nodes (bb); phi; phi = PHI_CHAIN (phi))
+           {
+             lhs = PHI_RESULT (phi);
+
+             if (!is_gimple_reg (lhs))
+               continue;
+
+             FOR_EACH_PHI_ARG (uop, phi, soi, SSA_OP_USE)
+               {
+                 rhs = USE_FROM_PTR (uop);
+                 if (va_list_ptr_read (&si, rhs, lhs))
+                   continue;
+                 else if (va_list_ptr_write (&si, lhs, rhs))
+                   continue;
+                 else
+                   check_va_list_escapes (&si, lhs, rhs);
+
+                 if (si.va_list_escapes
+                     || walk_tree (&phi, find_va_list_reference,
+                                   si.va_list_vars, NULL))
+                   {
+                     if (dump_file && (dump_flags & TDF_DETAILS))
+                       {
+                         fputs ("va_list escapes in ", dump_file);
+                         print_generic_expr (dump_file, phi, dump_flags);
+                         fputc ('\n', dump_file);
+                       }
+                     va_list_escapes = true;
+                   }
+               }
+           }
+       }
+
       for (i = bsi_start (bb);
           !bsi_end_p (i) && !va_list_escapes;
           bsi_next (&i))
@@ -856,6 +903,7 @@ finish:
        fprintf (dump_file, "%d", cfun->va_list_fpr_size);
       fputs (" FPR units.\n", dump_file);
     }
+  return 0;
 }