2009-07-31 Andrew Haley <aph@redhat.com>

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

diff --git a/gcc/tree-ssa-math-opts.c b/gcc/tree-ssa-math-opts.c
index 7e4e1bd..11ce546 100644 (file)
--- a/gcc/tree-ssa-math-opts.c
+++ b/gcc/tree-ssa-math-opts.c
@@ -1125,9 +1125,14 @@ find_bswap (gimple stmt)
   struct symbolic_number n;
   tree source_expr;
 
+  /* The last parameter determines the depth search limit.  It usually
+     correlates directly to the number of bytes to be touched.  We
+     increase that number by one here in order to also cover signed ->
+     unsigned conversions of the src operand as can be seen in
+     libgcc.  */
   source_expr =  find_bswap_1 (stmt, &n,
                               TREE_INT_CST_LOW (
-                                TYPE_SIZE_UNIT (gimple_expr_type (stmt))));
+                                TYPE_SIZE_UNIT (gimple_expr_type (stmt))) + 1);
 
   if (!source_expr)
     return NULL_TREE;
@@ -1159,6 +1164,7 @@ execute_optimize_bswap (void)
   basic_block bb;
   bool bswap32_p, bswap64_p;
   bool changed = false;
+  tree bswap32_type = NULL_TREE, bswap64_type = NULL_TREE;
 
   if (BITS_PER_UNIT != 8)
     return 0;
@@ -1176,6 +1182,20 @@ execute_optimize_bswap (void)
   if (!bswap32_p && !bswap64_p)
     return 0;
 
+  /* Determine the argument type of the builtins.  The code later on
+     assumes that the return and argument type are the same.  */
+  if (bswap32_p)
+    {
+      tree fndecl = built_in_decls[BUILT_IN_BSWAP32];
+      bswap32_type = TREE_VALUE (TYPE_ARG_TYPES (TREE_TYPE (fndecl)));
+    }
+
+  if (bswap64_p)
+    {
+      tree fndecl = built_in_decls[BUILT_IN_BSWAP64];
+      bswap64_type = TREE_VALUE (TYPE_ARG_TYPES (TREE_TYPE (fndecl)));
+    }
+
   FOR_EACH_BB (bb)
     {
       gimple_stmt_iterator gsi;
@@ -1183,7 +1203,8 @@ execute_optimize_bswap (void)
       for (gsi = gsi_after_labels (bb); !gsi_end_p (gsi); gsi_next (&gsi))
         {
          gimple stmt = gsi_stmt (gsi);
-         tree bswap_src;
+         tree bswap_src, bswap_type;
+         tree bswap_tmp;
          tree fndecl = NULL_TREE;
          int type_size;
          gimple call;
@@ -1198,11 +1219,17 @@ execute_optimize_bswap (void)
            {
            case 32:
              if (bswap32_p)
-               fndecl = built_in_decls[BUILT_IN_BSWAP32];
+               {
+                 fndecl = built_in_decls[BUILT_IN_BSWAP32];
+                 bswap_type = bswap32_type;
+               }
              break;
            case 64:
              if (bswap64_p)
-               fndecl = built_in_decls[BUILT_IN_BSWAP64];
+               {
+                 fndecl = built_in_decls[BUILT_IN_BSWAP64];
+                 bswap_type = bswap64_type;
+               }
              break;
            default:
              continue;
@@ -1217,8 +1244,41 @@ execute_optimize_bswap (void)
            continue;
 
          changed = true;
-         call = gimple_build_call (fndecl, 1, bswap_src);
-         gimple_call_set_lhs (call, gimple_assign_lhs (stmt));
+
+         bswap_tmp = bswap_src;
+
+         /* Convert the src expression if necessary.  */
+         if (!useless_type_conversion_p (TREE_TYPE (bswap_tmp), bswap_type))
+           {
+             gimple convert_stmt;
+
+             bswap_tmp = create_tmp_var (bswap_type, "bswapsrc");
+             add_referenced_var (bswap_tmp);
+             bswap_tmp = make_ssa_name (bswap_tmp, NULL);
+
+             convert_stmt = gimple_build_assign_with_ops (
+                              CONVERT_EXPR, bswap_tmp, bswap_src, NULL);
+             gsi_insert_before (&gsi, convert_stmt, GSI_SAME_STMT);
+           }
+
+         call = gimple_build_call (fndecl, 1, bswap_tmp);
+
+         bswap_tmp = gimple_assign_lhs (stmt);
+
+         /* Convert the result if necessary.  */
+         if (!useless_type_conversion_p (TREE_TYPE (bswap_tmp), bswap_type))
+           {
+             gimple convert_stmt;
+
+             bswap_tmp = create_tmp_var (bswap_type, "bswapdst");
+             add_referenced_var (bswap_tmp);
+             bswap_tmp = make_ssa_name (bswap_tmp, NULL);
+             convert_stmt = gimple_build_assign_with_ops (
+                              CONVERT_EXPR, gimple_assign_lhs (stmt), bswap_tmp, NULL);
+             gsi_insert_after (&gsi, convert_stmt, GSI_SAME_STMT);
+           }
+
+         gimple_call_set_lhs (call, bswap_tmp);
 
          if (dump_file)
            {