libcpp/

[pf3gnuchains/gcc-fork.git] / gcc / tree-ssa-propagate.c

diff --git a/gcc/tree-ssa-propagate.c b/gcc/tree-ssa-propagate.c
index b787aae..1981fa1 100644 (file)
--- a/gcc/tree-ssa-propagate.c
+++ b/gcc/tree-ssa-propagate.c
@@ -615,7 +615,6 @@ set_rhs (tree *stmt_p, tree expr)
            return false;
          break;
 
-       case CALL_EXPR:
        case EXC_PTR_EXPR:
        case FILTER_EXPR:
          break;
@@ -625,6 +624,16 @@ set_rhs (tree *stmt_p, tree expr)
        }
       break;
 
+    case tcc_vl_exp:
+      switch (code)
+       {
+       case CALL_EXPR:
+         break;
+       default:
+         return false;
+       }
+      break;
+
     case tcc_exceptional:
       switch (code)
        {
@@ -749,7 +758,7 @@ ssa_propagate (ssa_prop_visit_stmt_fn visit_stmt,
 }
 
 
-/* Return the first V_MAY_DEF or V_MUST_DEF operand for STMT.  */
+/* Return the first VDEF operand for STMT.  */
 
 tree
 first_vdef (tree stmt)
@@ -778,7 +787,7 @@ stmt_makes_single_load (tree stmt)
   if (TREE_CODE (stmt) != GIMPLE_MODIFY_STMT)
     return false;
 
-  if (ZERO_SSA_OPERANDS (stmt, SSA_OP_VMAYDEF|SSA_OP_VUSE))
+  if (ZERO_SSA_OPERANDS (stmt, SSA_OP_VDEF|SSA_OP_VUSE))
     return false;
 
   rhs = GIMPLE_STMT_OPERAND (stmt, 1);
@@ -803,7 +812,7 @@ stmt_makes_single_store (tree stmt)
   if (TREE_CODE (stmt) != GIMPLE_MODIFY_STMT)
     return false;
 
-  if (ZERO_SSA_OPERANDS (stmt, SSA_OP_VMAYDEF|SSA_OP_VMUSTDEF))
+  if (ZERO_SSA_OPERANDS (stmt, SSA_OP_VDEF))
     return false;
 
   lhs = GIMPLE_STMT_OPERAND (stmt, 0);
@@ -906,7 +915,7 @@ replace_uses_in (tree stmt, bool *replaced_addresses_p,
       GIMPLE register, then we are making a copy/constant propagation
       from a memory store.  For instance,
 
-       # a_3 = V_MAY_DEF <a_2>
+       # a_3 = VDEF <a_2>
        a.b = x_1;
        ...
        # VUSE <a_3>
@@ -917,8 +926,8 @@ replace_uses_in (tree stmt, bool *replaced_addresses_p,
       the VUSE(s) that we are replacing.  Otherwise, we may do the
       wrong replacement:
 
-       # a_3 = V_MAY_DEF <a_2>
-       # b_5 = V_MAY_DEF <b_4>
+       # a_3 = VDEF <a_2>
+       # b_5 = VDEF <b_4>
        *p = 10;
        ...
        # VUSE <b_5>
@@ -938,10 +947,10 @@ replace_uses_in (tree stmt, bool *replaced_addresses_p,
       stored in different locations:
 
                if (...)
-                 # a_3 = V_MAY_DEF <a_2>
+                 # a_3 = VDEF <a_2>
                  a.b = 3;
                else
-                 # a_4 = V_MAY_DEF <a_2>
+                 # a_4 = VDEF <a_2>
                  a.c = 3;
                # a_5 = PHI <a_3, a_4>
 
@@ -1103,7 +1112,7 @@ fold_predicate_in (tree stmt)
   else
     return false;
 
-  val = vrp_evaluate_conditional (*pred_p, true);
+  val = vrp_evaluate_conditional (*pred_p, stmt);
   if (val)
     {
       if (modify_stmt_p)
@@ -1137,15 +1146,18 @@ fold_predicate_in (tree stmt)
    expressions are evaluated with a call to vrp_evaluate_conditional.
    This will only give meaningful results when called from tree-vrp.c
    (the information used by vrp_evaluate_conditional is built by the
-   VRP pass).  */
+   VRP pass).  
 
-void
+   Return TRUE when something changed.  */
+
+bool
 substitute_and_fold (prop_value_t *prop_value, bool use_ranges_p)
 {
   basic_block bb;
+  bool something_changed = false;
 
   if (prop_value == NULL && !use_ranges_p)
-    return;
+    return false;
 
   if (dump_file && (dump_flags & TDF_DETAILS))
     fprintf (dump_file, "\nSubstituing values and folding statements\n\n");
@@ -1176,6 +1188,9 @@ substitute_and_fold (prop_value_t *prop_value, bool use_ranges_p)
              && TREE_CODE (GIMPLE_STMT_OPERAND (stmt, 1)) == ASSERT_EXPR)
            continue;
 
+         /* Record the state of the statement before replacements.  */
+         push_stmt_changes (bsi_stmt_ptr (i));
+
          /* Replace the statement with its folded version and mark it
             folded.  */
          did_replace = false;
@@ -1211,10 +1226,6 @@ substitute_and_fold (prop_value_t *prop_value, bool use_ranges_p)
              fold_stmt (bsi_stmt_ptr (i));
              stmt = bsi_stmt (i);
 
-             /* If we folded a builtin function, we'll likely
-                need to rename VDEFs.  */
-             mark_new_vars_to_rename (stmt);
-
               /* If we cleaned up EH information from the statement,
                  remove EH edges.  */
              if (maybe_clean_or_replace_eh_stmt (old_stmt, stmt))
@@ -1232,6 +1243,15 @@ substitute_and_fold (prop_value_t *prop_value, bool use_ranges_p)
                  print_generic_stmt (dump_file, stmt, TDF_SLIM);
                  fprintf (dump_file, "\n");
                }
+
+             /* Determine what needs to be done to update the SSA form.  */
+             pop_stmt_changes (bsi_stmt_ptr (i));
+             something_changed = true;
+           }
+         else
+           {
+             /* The statement was not modified, discard the change buffer.  */
+             discard_stmt_changes (bsi_stmt_ptr (i));
            }
 
          /* Some statements may be simplified using ranges.  For
@@ -1242,7 +1262,6 @@ substitute_and_fold (prop_value_t *prop_value, bool use_ranges_p)
             statement.  */
          if (use_ranges_p)
            simplify_stmt_using_ranges (stmt);
-
        }
     }
 
@@ -1255,6 +1274,7 @@ substitute_and_fold (prop_value_t *prop_value, bool use_ranges_p)
       fprintf (dump_file, "Predicates folded:    %6ld\n",
               prop_stats.num_pred_folded);
     }
+  return something_changed;
 }
 
 #include "gt-tree-ssa-propagate.h"