2009-10-13 Steve Ellcey <sje@cup.hp.com>

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

diff --git a/gcc/tree-ssa-live.c b/gcc/tree-ssa-live.c
index 0673fab..6d2fb32 100644 (file)
--- a/gcc/tree-ssa-live.c
+++ b/gcc/tree-ssa-live.c
@@ -435,6 +435,17 @@ remove_unused_scope_block_p (tree scope)
         will be output to file.  */
       if (TREE_CODE (*t) == FUNCTION_DECL)
        unused = false;
+
+      /* If a decl has a value expr, we need to instantiate it
+        regardless of debug info generation, to avoid codegen
+        differences in memory overlap tests.  update_equiv_regs() may
+        indirectly call validate_equiv_mem() to test whether a
+        SET_DEST overlaps with others, and if the value expr changes
+        by virtual register instantiation, we may get end up with
+        different results.  */
+      else if (TREE_CODE (*t) == VAR_DECL && DECL_HAS_VALUE_EXPR_P (*t))
+       unused = false;
+
       /* Remove everything we don't generate debug info for.  */
       else if (DECL_IGNORED_P (*t))
        {
@@ -525,7 +536,25 @@ remove_unused_scope_block_p (tree scope)
    /* For terse debug info we can eliminate info on unused variables.  */
    else if (debug_info_level == DINFO_LEVEL_NONE
            || debug_info_level == DINFO_LEVEL_TERSE)
-     ;
+     {
+       /* Even for -g0/-g1 don't prune outer scopes from artificial
+         functions, otherwise diagnostics using tree_nonartificial_location
+         will not be emitted properly.  */
+       if (inlined_function_outer_scope_p (scope))
+        {
+          tree ao = scope;
+
+          while (ao
+                 && TREE_CODE (ao) == BLOCK
+                 && BLOCK_ABSTRACT_ORIGIN (ao) != ao)
+            ao = BLOCK_ABSTRACT_ORIGIN (ao);
+          if (ao
+              && TREE_CODE (ao) == FUNCTION_DECL
+              && DECL_DECLARED_INLINE_P (ao)
+              && lookup_attribute ("artificial", DECL_ATTRIBUTES (ao)))
+            unused = false;
+        }
+     }
    else if (BLOCK_VARS (scope) || BLOCK_NUM_NONLOCALIZED_VARS (scope))
      unused = false;
    /* See if this block is important for representation of inlined function.
@@ -552,7 +581,9 @@ mark_all_vars_used (tree *expr_p, void *data)
   walk_tree (expr_p, mark_all_vars_used_1, data, NULL);
 }
 
-/* Dump scope blocks.  */
+
+/* Dump scope blocks starting at SCOPE to FILE.  INDENT is the
+   indentation level and FLAGS is as in print_generic_expr.  */
 
 static void
 dump_scope_block (FILE *file, int indent, tree scope, int flags)
@@ -606,12 +637,35 @@ dump_scope_block (FILE *file, int indent, tree scope, int flags)
   fprintf (file, "\n%*s}\n",indent, "");
 }
 
+/* Dump the tree of lexical scopes starting at SCOPE to stderr.  FLAGS
+   is as in print_generic_expr.  */
+
+void
+debug_scope_block (tree scope, int flags)
+{
+  dump_scope_block (stderr, 0, scope, flags);
+}
+
+
+/* Dump the tree of lexical scopes of current_function_decl to FILE.
+   FLAGS is as in print_generic_expr.  */
+
 void
 dump_scope_blocks (FILE *file, int flags)
 {
   dump_scope_block (file, 0, DECL_INITIAL (current_function_decl), flags);
 }
 
+
+/* Dump the tree of lexical scopes of current_function_decl to stderr.
+   FLAGS is as in print_generic_expr.  */
+
+void
+debug_scope_blocks (int flags)
+{
+  dump_scope_blocks (stderr, flags);
+}
+
 /* Remove local variables that are not referenced in the IL.  */
 
 void
@@ -623,6 +677,12 @@ remove_unused_locals (void)
   var_ann_t ann;
   bitmap global_unused_vars = NULL;
 
+  /* Removing declarations from lexical blocks when not optimizing is
+     not only a waste of time, it actually causes differences in stack
+     layout.  */
+  if (!optimize)
+    return;
+
   mark_scope_block_unused (DECL_INITIAL (current_function_decl));
 
   /* Assume all locals are unused.  */
@@ -643,6 +703,9 @@ remove_unused_locals (void)
          gimple stmt = gsi_stmt (gsi);
          tree b = gimple_block (stmt);
 
+         if (is_gimple_debug (stmt))
+           continue;
+
          if (b)
            TREE_USED (b) = true;
 
@@ -685,8 +748,7 @@ remove_unused_locals (void)
 
       if (TREE_CODE (var) != FUNCTION_DECL
          && (!(ann = var_ann (var))
-             || !ann->used)
-         && (optimize || DECL_ARTIFICIAL (var)))
+             || !ann->used))
        {
          if (is_global_var (var))
            {
@@ -745,8 +807,8 @@ remove_unused_locals (void)
        && TREE_CODE (t) != PARM_DECL
        && TREE_CODE (t) != RESULT_DECL
        && !(ann = var_ann (t))->used
-       && !TREE_ADDRESSABLE (t)
-       && (optimize || DECL_ARTIFICIAL (t)))
+       && !ann->is_heapvar
+       && !TREE_ADDRESSABLE (t))
       remove_referenced_var (t);
   remove_unused_scope_block_p (DECL_INITIAL (current_function_decl));
   if (dump_file && (dump_flags & TDF_DETAILS))
@@ -929,6 +991,8 @@ set_var_live_on_entry (tree ssa_name, tree_live_info_p live)
                add_block = e->src;
            }
        }
+      else if (is_gimple_debug (use_stmt))
+       continue;
       else
         {
          /* If its not defined in this block, its live on entry.  */