Update copyright years.

[thirdparty/gcc.git] / gcc / tree-into-ssa.c

diff --git a/gcc/tree-into-ssa.c b/gcc/tree-into-ssa.c
index c27bf2ce121533b6d509431b718673d98a6eb228..ef99060403039082435c0a6fc6d8922e3b375237 100644 (file)
--- a/gcc/tree-into-ssa.c
+++ b/gcc/tree-into-ssa.c
@@ -1,5 +1,5 @@
 /* Rewrite a program in Normal form into SSA.
-   Copyright (C) 2001-2020 Free Software Foundation, Inc.
+   Copyright (C) 2001-2021 Free Software Foundation, Inc.
    Contributed by Diego Novillo <dnovillo@redhat.com>
 
 This file is part of GCC.
@@ -41,6 +41,7 @@ along with GCC; see the file COPYING3.  If not see
 #include "stringpool.h"
 #include "attribs.h"
 #include "asan.h"
+#include "attr-fnspec.h"
 
 #define PERCENT(x,y) ((float)(x) * 100.0 / (float)(y))
 
@@ -323,7 +324,7 @@ get_ssa_name_ann (tree name)
 
   /* Re-allocate the vector at most once per update/into-SSA.  */
   if (ver >= len)
-    info_for_ssa_name.safe_grow_cleared (num_ssa_names);
+    info_for_ssa_name.safe_grow_cleared (num_ssa_names, true);
 
   /* But allocate infos lazily.  */
   info = info_for_ssa_name[ver];
@@ -944,7 +945,7 @@ mark_phi_for_rewrite (basic_block bb, gphi *phi)
     {
       n = (unsigned) last_basic_block_for_fn (cfun) + 1;
       if (phis_to_rewrite.length () < n)
-       phis_to_rewrite.safe_grow_cleared (n);
+       phis_to_rewrite.safe_grow_cleared (n, true);
 
       phis = phis_to_rewrite[idx];
       gcc_assert (!phis.exists ());
@@ -1411,6 +1412,10 @@ rewrite_stmt (gimple_stmt_iterator *si)
        SET_DEF (def_p, name);
        register_new_def (DEF_FROM_PTR (def_p), var);
 
+       /* Do not insert debug stmts if the stmt ends the BB.  */
+       if (stmt_ends_bb_p (stmt))
+         continue;
+       
        tracked_var = target_for_debug_bind (var);
        if (tracked_var)
          {
@@ -2430,8 +2435,7 @@ pass_build_ssa::execute (function *fun)
   basic_block bb;
 
   /* Increase the set of variables we can rewrite into SSA form
-     by clearing TREE_ADDRESSABLE and setting DECL_GIMPLE_REG_P
-     and transform the IL to support this.  */
+     by clearing TREE_ADDRESSABLE and transform the IL to support this.  */
   if (optimize)
     execute_update_addresses_taken ();
 
@@ -2493,19 +2497,19 @@ pass_build_ssa::execute (function *fun)
     }
 
   /* Initialize SSA_NAME_POINTS_TO_READONLY_MEMORY.  */
-  tree fnspec = lookup_attribute ("fn spec",
-                                 TYPE_ATTRIBUTES (TREE_TYPE (fun->decl)));
-  if (fnspec)
+  tree fnspec_tree
+        = lookup_attribute ("fn spec",
+                            TYPE_ATTRIBUTES (TREE_TYPE (fun->decl)));
+  if (fnspec_tree)
     {
-      fnspec = TREE_VALUE (TREE_VALUE (fnspec));
-      unsigned i = 1;
+      attr_fnspec fnspec (TREE_VALUE (TREE_VALUE (fnspec_tree)));
+      unsigned i = 0;
       for (tree arg = DECL_ARGUMENTS (cfun->decl);
           arg; arg = DECL_CHAIN (arg), ++i)
        {
-         if (i >= (unsigned) TREE_STRING_LENGTH (fnspec))
-           break;
-         if (TREE_STRING_POINTER (fnspec)[i]  == 'R'
-             || TREE_STRING_POINTER (fnspec)[i] == 'r')
+         if (!fnspec.arg_specified_p (i))
+          break;
+         if (fnspec.arg_readonly_p (i))
            {
              tree name = ssa_default_def (fun, arg);
              if (name)
@@ -2593,11 +2597,9 @@ mark_use_interesting (tree var, gimple *stmt, basic_block bb,
     }
 }
 
-
-/* Do a dominator walk starting at BB processing statements that
-   reference symbols in SSA operands.  This is very similar to
-   mark_def_sites, but the scan handles statements whose operands may
-   already be SSA names.
+/* Processing statements in BB that reference symbols in SSA operands.
+   This is very similar to mark_def_sites, but the scan handles
+   statements whose operands may already be SSA names.
 
    If INSERT_PHI_P is true, mark those uses as live in the
    corresponding block.  This is later used by the PHI placement
@@ -2610,9 +2612,8 @@ mark_use_interesting (tree var, gimple *stmt, basic_block bb,
           that.  */
 
 static void
-prepare_block_for_update (basic_block bb, bool insert_phi_p)
+prepare_block_for_update_1 (basic_block bb, bool insert_phi_p)
 {
-  basic_block son;
   edge e;
   edge_iterator ei;
 
@@ -2694,13 +2695,51 @@ prepare_block_for_update (basic_block bb, bool insert_phi_p)
        }
     }
 
-  /* Now visit all the blocks dominated by BB.  */
-  for (son = first_dom_son (CDI_DOMINATORS, bb);
-       son;
-       son = next_dom_son (CDI_DOMINATORS, son))
-    prepare_block_for_update (son, insert_phi_p);
 }
 
+/* Do a dominator walk starting at BB processing statements that
+   reference symbols in SSA operands.  This is very similar to
+   mark_def_sites, but the scan handles statements whose operands may
+   already be SSA names.
+
+   If INSERT_PHI_P is true, mark those uses as live in the
+   corresponding block.  This is later used by the PHI placement
+   algorithm to make PHI pruning decisions.
+
+   FIXME.  Most of this would be unnecessary if we could associate a
+          symbol to all the SSA names that reference it.  But that
+          sounds like it would be expensive to maintain.  Still, it
+          would be interesting to see if it makes better sense to do
+          that.  */
+static void
+prepare_block_for_update (basic_block bb, bool insert_phi_p)
+{
+  size_t sp = 0;
+  basic_block *worklist;
+
+  /* Allocate the worklist.  */
+  worklist = XNEWVEC (basic_block, n_basic_blocks_for_fn (cfun));
+  /* Add the BB to the worklist.  */
+  worklist[sp++] = bb;
+
+  while (sp)
+    {
+      basic_block bb;
+      basic_block son;
+
+      /* Pick a block from the worklist.  */
+      bb = worklist[--sp];
+
+      prepare_block_for_update_1 (bb, insert_phi_p);
+
+      /* Now add all the blocks dominated by BB to the worklist.  */
+      for (son = first_dom_son (CDI_DOMINATORS, bb);
+          son;
+          son = next_dom_son (CDI_DOMINATORS, son))
+       worklist[sp++] = son;
+    }
+  free (worklist);
+}
 
 /* Helper for prepare_names_to_update.  Mark all the use sites for
    NAME as interesting.  BLOCKS and INSERT_PHI_P are as in