[PATCH] Multiversioning fixes (PR c++/55742)

[PATCH] Multiversioning fixes (PR c++/55742)

[Jakub Jelinek]

Hi!

As discussed in the PR, this patch attempts to change multiversioning
so that backwards compatibility with the previous target attribute behavior
is preserved.  In particular, e.g. for
void foo () __attribute__((target ("avx")));
void foo ()
{
}

the foo definition was just merged with the previous declaration and
used the avx target attribute.  The patch introduces
target ("default")
which should be used if a default multiversion variant is desirable.

Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?

I've mentioned a bunch of other issues with multiversioning in the PR
(including missing documentation for the feature), hope those can be
resolved incrementally.

2013-01-18  Jakub Jelinek  <jakub@redhat.com>

	PR c++/55742
	* config/i386/i386.c (ix86_valid_target_attribute_inner_p): Diagnose
	invalid args instead of ICEing on it.
	(ix86_valid_target_attribute_p): Allow target("default") attribute.
	(sorted_attr_string): Formatting fix.
	(ix86_mangle_function_version_assembler_n): Mangle target("default")
	as if no target attribute is present.
	(ix86_function_versions): Don't return true if one of the decls
	doesn't have target attribute.  If they don't and one of the decls
	is DECL_FUNCTION_VERSIONED, report an error.
	(is_function_default_version): Return true if there is
	target("default") attribute rather than no target attribute at all.

	* g++.dg/mv1.C: Adjust test.
	* g++.dg/mv2.C: Likewise.
	* g++.dg/mv5.C: Likewise.
	* g++.dg/mv6.C: Likewise.

--- gcc/config/i386/i386.c.jj	2013-01-18 17:59:41.692943971 +0100
+++ gcc/config/i386/i386.c	2013-01-18 18:43:21.105326012 +0100
@@ -4223,7 +4223,10 @@ ix86_valid_target_attribute_inner_p (tre
     }
 
   else if (TREE_CODE (args) != STRING_CST)
-    gcc_unreachable ();
+    {
+      error ("invalid %<target%> attribute value");
+      return false;
+    }
 
   /* Handle multiple arguments separated by commas.  */
   next_optstr = ASTRDUP (TREE_STRING_POINTER (args));
@@ -4433,6 +4436,15 @@ ix86_valid_target_attribute_p (tree fnde
 {
   struct cl_target_option cur_target;
   bool ret = true;
+
+  /* attribute((target("default"))) does nothing, beyond
+     affecting multi-versioning.  */
+  if (TREE_VALUE (args)
+      && TREE_CODE (TREE_VALUE (args)) == STRING_CST
+      && TREE_CHAIN (args) == NULL_TREE
+      && strcmp (TREE_STRING_POINTER (TREE_VALUE (args)), "default") == 0)
+    return true;
+
   tree old_optimize = build_optimization_node ();
   tree new_target, new_optimize;
   tree func_optimize = DECL_FUNCTION_SPECIFIC_OPTIMIZATION (fndecl);
@@ -28964,7 +28976,7 @@ sorted_attr_string (const char *str)
     if (str[i] == ',')
       argnum++;
 
-  attr_str = (char *)xmalloc (strlen (str) + 1);
+  attr_str = (char *) xmalloc (strlen (str) + 1);
   strcpy (attr_str, str);
 
   /* Replace "=,-" with "_".  */
@@ -29034,6 +29046,9 @@ ix86_mangle_function_version_assembler_n
   version_string
     = TREE_STRING_POINTER (TREE_VALUE (TREE_VALUE (version_attr)));
 
+  if (strcmp (version_string, "default") == 0)
+    return id;
+
   attr_str = sorted_attr_string (version_string);
   assembler_name = (char *) xmalloc (strlen (orig_name)
 				     + strlen (attr_str) + 2);
@@ -29058,7 +29073,7 @@ ix86_function_versions (tree fn1, tree f
   const char *attr_str1, *attr_str2;
   char *target1, *target2;
   bool result;
-  
+
   if (TREE_CODE (fn1) != FUNCTION_DECL
       || TREE_CODE (fn2) != FUNCTION_DECL)
     return false;
@@ -29070,12 +29085,35 @@ ix86_function_versions (tree fn1, tree f
   if (attr1 == NULL_TREE && attr2 == NULL_TREE)
     return false;
 
-  /* If one function does not have a target attribute, these are versions.  */
+  /* Diagnose missing target attribute if one of the decls is already
+     multi-versioned.  */
   if (attr1 == NULL_TREE || attr2 == NULL_TREE)
-    return true;
+    {
+      if (DECL_FUNCTION_VERSIONED (fn1) || DECL_FUNCTION_VERSIONED (fn2))
+	{
+	  if (attr2 != NULL_TREE)
+	    {
+	      tree tem = fn1;
+	      fn1 = fn2;
+	      fn2 = tem;
+	      attr1 = attr2;
+	    }
+	  error_at (DECL_SOURCE_LOCATION (fn2),
+		    "missing %<target%> attribute for multi-versioned %D",
+		    fn2);
+	  error_at (DECL_SOURCE_LOCATION (fn1),
+		    "previous declaration of %D", fn1);
+	  /* Prevent diagnosing of the same error multiple times.  */
+	  DECL_ATTRIBUTES (fn2)
+	    = tree_cons (get_identifier ("target"),
+			 copy_node (TREE_VALUE (attr1)),
+			 DECL_ATTRIBUTES (fn2));
+	}
+      return false;
+    }
 
-  attr_str1 =  TREE_STRING_POINTER (TREE_VALUE (TREE_VALUE (attr1)));
-  attr_str2 =  TREE_STRING_POINTER (TREE_VALUE (TREE_VALUE (attr2)));
+  attr_str1 = TREE_STRING_POINTER (TREE_VALUE (TREE_VALUE (attr1)));
+  attr_str2 = TREE_STRING_POINTER (TREE_VALUE (TREE_VALUE (attr2)));
 
   target1 = sorted_attr_string (attr_str1);
   target2 = sorted_attr_string (attr_str2);
@@ -29196,9 +29234,14 @@ make_dispatcher_decl (const tree decl)
 static bool
 is_function_default_version (const tree decl)
 {
-  return (TREE_CODE (decl) == FUNCTION_DECL
-	  && DECL_FUNCTION_VERSIONED (decl)
-	  && lookup_attribute ("target", DECL_ATTRIBUTES (decl)) == NULL_TREE);
+  if (TREE_CODE (decl) != FUNCTION_DECL
+      || !DECL_FUNCTION_VERSIONED (decl))
+    return false;
+  tree attr = lookup_attribute ("target", DECL_ATTRIBUTES (decl));
+  gcc_assert (attr);
+  attr = TREE_VALUE (TREE_VALUE (attr));
+  return (TREE_CODE (attr) == STRING_CST
+	  && strcmp (TREE_STRING_POINTER (attr), "default") == 0);
 }
 
 /* Make a dispatcher declaration for the multi-versioned function DECL.
--- gcc/testsuite/g++.dg/mv1.C.jj	2013-01-18 17:59:41.567944606 +0100
+++ gcc/testsuite/g++.dg/mv1.C	2013-01-18 18:31:36.223533556 +0100
@@ -6,7 +6,7 @@
 #include <assert.h>
 
 /* Default version.  */
-int foo ();
+int foo () __attribute__ ((target("default")));
 /* The other versions of foo.  Mix up the ordering and 
    check if the dispatching does it in the order of priority. */
 /* Check combination of target attributes.  */
@@ -65,7 +65,8 @@ int main ()
   return 0;
 }
 
-int foo ()
+int __attribute__ ((target("default")))
+foo ()
 {
   return 0;
 }
--- gcc/testsuite/g++.dg/mv2.C.jj	2013-01-18 17:59:41.456945279 +0100
+++ gcc/testsuite/g++.dg/mv2.C	2013-01-18 18:31:36.224533535 +0100
@@ -7,7 +7,7 @@
 #include <assert.h>
 
 /* Default version.  */
-int foo ();
+int foo () __attribute__ ((target ("default")));
 /* The dispatch checks should be in the exact reverse order of the
    declarations below.  */
 int foo () __attribute__ ((target ("mmx")));
@@ -51,7 +51,7 @@ int main ()
   return 0;
 }
 
-int
+int __attribute__ ((target("default")))
 foo ()
 {
   return 0;
--- gcc/testsuite/g++.dg/mv5.C.jj	2013-01-18 17:59:41.587944512 +0100
+++ gcc/testsuite/g++.dg/mv5.C	2013-01-18 18:31:36.224533535 +0100
@@ -7,7 +7,7 @@
 
 
 /* Default version.  */
-inline int
+inline int __attribute__ ((target ("default")))
 foo ()
 {
   return 0;
--- gcc/testsuite/g++.dg/mv6.C.jj	2013-01-18 17:59:41.507944953 +0100
+++ gcc/testsuite/g++.dg/mv6.C	2013-01-18 18:31:36.224533535 +0100
@@ -8,6 +8,7 @@ class Foo
 {
  public:
   /* Default version of foo.  */
+  __attribute__ ((target("default")))
   int foo ()
   {
     return 0;


	Jakub

Re: [PATCH] Multiversioning fixes (PR c++/55742)

[Jason Merrill]

On 01/18/2013 03:22 PM, Jakub Jelinek wrote:
>     else if (TREE_CODE (args) != STRING_CST)
> -    gcc_unreachable ();
> +    {
> +      error ("invalid %<target%> attribute value");
> +      return false;
> +    }

Maybe say that it needs to be a string?

We also need more tests, both for the example in the PR (and your 
introductory text) and for error cases.

Thanks,
Jason

[PATCH] Multiversioning fixes (PR c++/55742, take 2)

[Jakub Jelinek]

On Sat, Jan 19, 2013 at 11:19:04AM -0500, Jason Merrill wrote:
> On 01/18/2013 03:22 PM, Jakub Jelinek wrote:
> >    else if (TREE_CODE (args) != STRING_CST)
> >-    gcc_unreachable ();
> >+    {
> >+      error ("invalid %<target%> attribute value");
> >+      return false;
> >+    }
> 
> Maybe say that it needs to be a string?

Fixed, using the wording of another attribute handler in c-common.c.

> We also need more tests, both for the example in the PR (and your
> introductory text) and for error cases.

Added a few ones, merged the patch with the incremental one, fixed handling
of target ("popcnt", "avx") as opposed to target ("popcnt,avx") that was
the only thing handled before by mv, fixed a bunch of memory leaks and
formatting issues, moved tests to g++.dg/ext/ and added a couple of new
ones.

Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?

I hope documentation (which is for multiversioning missing completely right
now) and further testcases can be added incrementally.

2013-01-21  Jakub Jelinek  <jakub@redhat.com>

	PR c++/55742
	* config/i386/i386.c (ix86_valid_target_attribute_inner_p): Diagnose
	invalid args instead of ICEing on it.
	(ix86_valid_target_attribute_tree): Return error_mark_node if
	ix86_valid_target_attribute_inner_p failed.
	(ix86_valid_target_attribute_p): Return false only if
	ix86_valid_target_attribute_tree returned error_mark_node.  Allow
	target("default") attribute.
	(sorted_attr_string): Change argument from const char * to tree,
	merge in all target attribute arguments rather than just one.
	Formatting fix.  Use XNEWVEC instead of xmalloc and XDELETEVEC
	instead of free.  Avoid using strcat.
	(ix86_mangle_function_version_assembler_name): Mangle
	target("default") as if no target attribute is present.  Adjust
	sorted_attr_string caller.  Avoid leaking memory.  Use XNEWVEC
	instead of xmalloc and XDELETEVEC instead of free.
	(ix86_function_versions): Don't return true if one of the decls
	doesn't have target attribute.  If they don't and one of the decls
	is DECL_FUNCTION_VERSIONED, report an error.  Adjust
	sorted_attr_string caller.  Use XDELETEVEC instead of free.
	(ix86_supports_function_versions): Remove.
	(make_name): Fix up formatting.
	(make_dispatcher_decl): Remove resolver_name and its initialization.
	Avoid leaking memory.
	(is_function_default_version): Return true if there is
	target("default") attribute rather than no target attribute at all.
	(make_resolver_func): Avoid leaking memory.
	(ix86_generate_version_dispatcher_body): Likewise.
	(TARGET_OPTION_SUPPORTS_FUNCTION_VERSIONS): Remove.
	* target.def (supports_function_versions): Remove.
	* doc/tm.texi.in (SUPPORTS_FUNCTION_VERSIONS): Remove.
	* doc/tm.texi: Regenerated.

	* c-common.c (handle_target_attribute): Revert 2012-12-26 change.

	* g++.dg/mv1.C: Moved to...
	* g++.dg/ext/mv1.C: ... here.  Adjust test.
	* g++.dg/mv2.C: Moved to...
	* g++.dg/ext/mv2.C: ... here.  Adjust test.
	* g++.dg/mv3.C: Moved to...
	* g++.dg/ext/mv3.C: ... here.
	* g++.dg/mv4.C: Moved to...
	* g++.dg/ext/mv4.C: ... here.
	* g++.dg/mv5.C: Moved to...
	* g++.dg/ext/mv5.C: ... here.  Adjust test.
	* g++.dg/mv6.C: Moved to...
	* g++.dg/ext/mv6.C: ... here.  Adjust test.
	* g++.dg/ext/mv7.C: New test.
	* g++.dg/ext/mv8.C: New test.
	* g++.dg/ext/mv9.C: New test.
	* g++.dg/ext/mv10.C: New test.
	* g++.dg/ext/mv11.C: New test.

--- gcc/config/i386/i386.c.jj	2013-01-21 10:57:08.325945469 +0100
+++ gcc/config/i386/i386.c	2013-01-21 12:02:59.384701394 +0100
@@ -4223,7 +4223,10 @@ ix86_valid_target_attribute_inner_p (tre
     }
 
   else if (TREE_CODE (args) != STRING_CST)
-    gcc_unreachable ();
+    {
+      error ("attribute %<target%> argument not a string");
+      return false;
+    }
 
   /* Handle multiple arguments separated by commas.  */
   next_optstr = ASTRDUP (TREE_STRING_POINTER (args));
@@ -4368,7 +4371,7 @@ ix86_valid_target_attribute_tree (tree a
   /* Process each of the options on the chain.  */
   if (! ix86_valid_target_attribute_inner_p (args, option_strings,
 					     &enum_opts_set))
-    return NULL_TREE;
+    return error_mark_node;
 
   /* If the changed options are different from the default, rerun
      ix86_option_override_internal, and then save the options away.
@@ -4433,6 +4436,15 @@ ix86_valid_target_attribute_p (tree fnde
 {
   struct cl_target_option cur_target;
   bool ret = true;
+
+  /* attribute((target("default"))) does nothing, beyond
+     affecting multi-versioning.  */
+  if (TREE_VALUE (args)
+      && TREE_CODE (TREE_VALUE (args)) == STRING_CST
+      && TREE_CHAIN (args) == NULL_TREE
+      && strcmp (TREE_STRING_POINTER (TREE_VALUE (args)), "default") == 0)
+    return true;
+
   tree old_optimize = build_optimization_node ();
   tree new_target, new_optimize;
   tree func_optimize = DECL_FUNCTION_SPECIFIC_OPTIMIZATION (fndecl);
@@ -4449,10 +4461,10 @@ ix86_valid_target_attribute_p (tree fnde
   new_target = ix86_valid_target_attribute_tree (args);
   new_optimize = build_optimization_node ();
 
-  if (!new_target)
+  if (new_target == error_mark_node)
     ret = false;
 
-  else if (fndecl)
+  else if (fndecl && new_target)
     {
       DECL_FUNCTION_SPECIFIC_TARGET (fndecl) = new_target;
 
@@ -28946,26 +28958,44 @@ attr_strcmp (const void *v1, const void
   return strcmp (c1, c2);
 }
 
-/* STR is the argument to target attribute.  This function tokenizes
+/* ARGLIST is the argument to target attribute.  This function tokenizes
    the comma separated arguments, sorts them and returns a string which
    is a unique identifier for the comma separated arguments.   It also
    replaces non-identifier characters "=,-" with "_".  */
 
 static char *
-sorted_attr_string (const char *str)
+sorted_attr_string (tree arglist)
 {
+  tree arg;
+  size_t str_len_sum = 0;
   char **args = NULL;
   char *attr_str, *ret_str;
   char *attr = NULL;
   unsigned int argnum = 1;
   unsigned int i;
 
-  for (i = 0; i < strlen (str); i++)
-    if (str[i] == ',')
-      argnum++;
-
-  attr_str = (char *)xmalloc (strlen (str) + 1);
-  strcpy (attr_str, str);
+  for (arg = arglist; arg; arg = TREE_CHAIN (arg))
+    {
+      const char *str = TREE_STRING_POINTER (TREE_VALUE (arg));
+      size_t len = strlen (str);
+      str_len_sum += len + 1;
+      if (arg != arglist)
+	argnum++;
+      for (i = 0; i < strlen (str); i++)
+	if (str[i] == ',')
+	  argnum++;
+    }
+
+  attr_str = XNEWVEC (char, str_len_sum);
+  str_len_sum = 0;
+  for (arg = arglist; arg; arg = TREE_CHAIN (arg))
+    {
+      const char *str = TREE_STRING_POINTER (TREE_VALUE (arg));
+      size_t len = strlen (str);
+      memcpy (attr_str + str_len_sum, str, len);
+      attr_str[str_len_sum + len] = TREE_CHAIN (arg) ? ',' : '\0';
+      str_len_sum += len + 1;
+    }
 
   /* Replace "=,-" with "_".  */
   for (i = 0; i < strlen (attr_str); i++)
@@ -28986,18 +29016,20 @@ sorted_attr_string (const char *str)
       attr = strtok (NULL, ",");
     }
 
-  qsort (args, argnum, sizeof (char*), attr_strcmp);
+  qsort (args, argnum, sizeof (char *), attr_strcmp);
 
-  ret_str = (char *)xmalloc (strlen (str) + 1);
-  strcpy (ret_str, args[0]);
-  for (i = 1; i < argnum; i++)
+  ret_str = XNEWVEC (char, str_len_sum);
+  str_len_sum = 0;
+  for (i = 0; i < argnum; i++)
     {
-      strcat (ret_str, "_");
-      strcat (ret_str, args[i]);
+      size_t len = strlen (args[i]);
+      memcpy (ret_str + str_len_sum, args[i], len);
+      ret_str[str_len_sum + len] = i < argnum - 1 ? '_' : '\0';
+      str_len_sum += len + 1;
     }
 
-  free (args);
-  free (attr_str);
+  XDELETEVEC (args);
+  XDELETEVEC (attr_str);
   return ret_str;
 }
 
@@ -29009,8 +29041,8 @@ static tree
 ix86_mangle_function_version_assembler_name (tree decl, tree id)
 {
   tree version_attr;
-  const char *orig_name, *version_string, *attr_str;
-  char *assembler_name;
+  const char *orig_name, *version_string;
+  char *attr_str, *assembler_name;
 
   if (DECL_DECLARED_INLINE_P (decl)
       && lookup_attribute ("gnu_inline",
@@ -29034,9 +29066,11 @@ ix86_mangle_function_version_assembler_n
   version_string
     = TREE_STRING_POINTER (TREE_VALUE (TREE_VALUE (version_attr)));
 
-  attr_str = sorted_attr_string (version_string);
-  assembler_name = (char *) xmalloc (strlen (orig_name)
-				     + strlen (attr_str) + 2);
+  if (strcmp (version_string, "default") == 0)
+    return id;
+
+  attr_str = sorted_attr_string (TREE_VALUE (version_attr));
+  assembler_name = XNEWVEC (char, strlen (orig_name) + strlen (attr_str) + 2);
 
   sprintf (assembler_name, "%s.%s", orig_name, attr_str);
 
@@ -29044,7 +29078,10 @@ ix86_mangle_function_version_assembler_n
   if (DECL_ASSEMBLER_NAME_SET_P (decl))
     SET_DECL_RTL (decl, NULL);
 
-  return get_identifier (assembler_name);
+  tree ret = get_identifier (assembler_name);
+  XDELETEVEC (attr_str);
+  XDELETEVEC (assembler_name);
+  return ret;
 }
 
 /* This function returns true if FN1 and FN2 are versions of the same function,
@@ -29055,10 +29092,9 @@ static bool
 ix86_function_versions (tree fn1, tree fn2)
 {
   tree attr1, attr2;
-  const char *attr_str1, *attr_str2;
   char *target1, *target2;
   bool result;
-  
+
   if (TREE_CODE (fn1) != FUNCTION_DECL
       || TREE_CODE (fn2) != FUNCTION_DECL)
     return false;
@@ -29070,15 +29106,35 @@ ix86_function_versions (tree fn1, tree f
   if (attr1 == NULL_TREE && attr2 == NULL_TREE)
     return false;
 
-  /* If one function does not have a target attribute, these are versions.  */
+  /* Diagnose missing target attribute if one of the decls is already
+     multi-versioned.  */
   if (attr1 == NULL_TREE || attr2 == NULL_TREE)
-    return true;
-
-  attr_str1 =  TREE_STRING_POINTER (TREE_VALUE (TREE_VALUE (attr1)));
-  attr_str2 =  TREE_STRING_POINTER (TREE_VALUE (TREE_VALUE (attr2)));
+    {
+      if (DECL_FUNCTION_VERSIONED (fn1) || DECL_FUNCTION_VERSIONED (fn2))
+	{
+	  if (attr2 != NULL_TREE)
+	    {
+	      tree tem = fn1;
+	      fn1 = fn2;
+	      fn2 = tem;
+	      attr1 = attr2;
+	    }
+	  error_at (DECL_SOURCE_LOCATION (fn2),
+		    "missing %<target%> attribute for multi-versioned %D",
+		    fn2);
+	  error_at (DECL_SOURCE_LOCATION (fn1),
+		    "previous declaration of %D", fn1);
+	  /* Prevent diagnosing of the same error multiple times.  */
+	  DECL_ATTRIBUTES (fn2)
+	    = tree_cons (get_identifier ("target"),
+			 copy_node (TREE_VALUE (attr1)),
+			 DECL_ATTRIBUTES (fn2));
+	}
+      return false;
+    }
 
-  target1 = sorted_attr_string (attr_str1);
-  target2 = sorted_attr_string (attr_str2);
+  target1 = sorted_attr_string (TREE_VALUE (attr1));
+  target2 = sorted_attr_string (TREE_VALUE (attr2));
 
   /* The sorted target strings must be different for fn1 and fn2
      to be versions.  */
@@ -29087,20 +29143,12 @@ ix86_function_versions (tree fn1, tree f
   else
     result = true;
 
-  free (target1);
-  free (target2); 
+  XDELETEVEC (target1);
+  XDELETEVEC (target2); 
   
   return result;
 }
 
-/* This target supports function multiversioning.  */
-
-static bool
-ix86_supports_function_versions (void)
-{
-  return true;
-}
-
 static tree 
 ix86_mangle_decl_assembler_name (tree decl, tree id)
 {
@@ -29141,10 +29189,10 @@ make_name (tree decl, const char *suffix
 
   /* Use '.' to concatenate names as it is demangler friendly.  */
   if (make_unique)
-      snprintf (global_var_name, name_len, "%s.%s.%s", name,
-		unique_name, suffix);
+    snprintf (global_var_name, name_len, "%s.%s.%s", name, unique_name,
+	      suffix);
   else
-      snprintf (global_var_name, name_len, "%s.%s", name, suffix);
+    snprintf (global_var_name, name_len, "%s.%s", name, suffix);
 
   return global_var_name;
 }
@@ -29159,7 +29207,7 @@ static tree
 make_dispatcher_decl (const tree decl)
 {
   tree func_decl;
-  char *func_name, *resolver_name;
+  char *func_name;
   tree fn_type, func_type;
   bool is_uniq = false;
 
@@ -29167,14 +29215,13 @@ make_dispatcher_decl (const tree decl)
     is_uniq = true;
 
   func_name = make_name (decl, "ifunc", is_uniq);
-  resolver_name = make_name (decl, "resolver", is_uniq);
-  gcc_assert (resolver_name);
 
   fn_type = TREE_TYPE (decl);
   func_type = build_function_type (TREE_TYPE (fn_type),
 				   TYPE_ARG_TYPES (fn_type));
   
   func_decl = build_fn_decl (func_name, func_type);
+  XDELETEVEC (func_name);
   TREE_USED (func_decl) = 1;
   DECL_CONTEXT (func_decl) = NULL_TREE;
   DECL_INITIAL (func_decl) = error_mark_node;
@@ -29196,9 +29243,14 @@ make_dispatcher_decl (const tree decl)
 static bool
 is_function_default_version (const tree decl)
 {
-  return (TREE_CODE (decl) == FUNCTION_DECL
-	  && DECL_FUNCTION_VERSIONED (decl)
-	  && lookup_attribute ("target", DECL_ATTRIBUTES (decl)) == NULL_TREE);
+  if (TREE_CODE (decl) != FUNCTION_DECL
+      || !DECL_FUNCTION_VERSIONED (decl))
+    return false;
+  tree attr = lookup_attribute ("target", DECL_ATTRIBUTES (decl));
+  gcc_assert (attr);
+  attr = TREE_VALUE (TREE_VALUE (attr));
+  return (TREE_CODE (attr) == STRING_CST
+	  && strcmp (TREE_STRING_POINTER (attr), "default") == 0);
 }
 
 /* Make a dispatcher declaration for the multi-versioned function DECL.
@@ -29392,6 +29444,7 @@ make_resolver_func (const tree default_d
   /* Create the alias for dispatch to resolver here.  */
   /*cgraph_create_function_alias (dispatch_decl, decl);*/
   cgraph_same_body_alias (NULL, dispatch_decl, decl);
+  XDELETEVEC (resolver_name);
   return decl;
 }
 
@@ -29453,7 +29506,7 @@ ix86_generate_version_dispatcher_body (v
     }
 
   dispatch_function_versions (resolver_decl, &fn_ver_vec, &empty_bb);
-
+  fn_ver_vec.release ();
   rebuild_cgraph_edges (); 
   pop_cfun ();
   return resolver_decl;
@@ -42441,10 +42494,6 @@ ix86_memmodel_check (unsigned HOST_WIDE_
 #undef TARGET_OPTION_FUNCTION_VERSIONS
 #define TARGET_OPTION_FUNCTION_VERSIONS ix86_function_versions
 
-#undef TARGET_OPTION_SUPPORTS_FUNCTION_VERSIONS
-#define TARGET_OPTION_SUPPORTS_FUNCTION_VERSIONS \
-  ix86_supports_function_versions
-
 #undef TARGET_CAN_INLINE_P
 #define TARGET_CAN_INLINE_P ix86_can_inline_p
 
--- gcc/target.def.jj	2013-01-11 09:02:32.000000000 +0100
+++ gcc/target.def	2013-01-21 11:25:29.145124702 +0100
@@ -2831,14 +2831,6 @@ DEFHOOK
  bool, (tree decl1, tree decl2),
  hook_bool_tree_tree_false)
 
-/* This function returns true if the target supports function
-   multiversioning.  */
-DEFHOOK
-(supports_function_versions,
- "",
- bool, (void),
- hook_bool_void_false)
-
 /* Function to determine if one function can inline another function.  */
 #undef HOOK_PREFIX
 #define HOOK_PREFIX "TARGET_"
--- gcc/doc/tm.texi.in.jj	2013-01-11 09:02:26.000000000 +0100
+++ gcc/doc/tm.texi.in	2013-01-21 11:25:57.789962584 +0100
@@ -9768,11 +9768,6 @@ different target specific attributes, th
 different target machines.
 @end deftypefn
 
-@hook TARGET_OPTION_SUPPORTS_FUNCTION_VERSIONS
-This target hook returns @code{true} if the target supports function
-multiversioning.
-@end deftypefn
-
 @hook TARGET_CAN_INLINE_P
 This target hook returns @code{false} if the @var{caller} function
 cannot inline @var{callee}, based on target specific information.  By
--- gcc/doc/tm.texi.jj	2013-01-11 09:02:26.000000000 +0100
+++ gcc/doc/tm.texi	2013-01-21 11:26:08.647897014 +0100
@@ -9907,11 +9907,6 @@ different target specific attributes, th
 different target machines.
 @end deftypefn
 
-@deftypefn {Target Hook} bool TARGET_OPTION_SUPPORTS_FUNCTION_VERSIONS (void)
-This target hook returns @code{true} if the target supports function
-multiversioning.
-@end deftypefn
-
 @deftypefn {Target Hook} bool TARGET_CAN_INLINE_P (tree @var{caller}, tree @var{callee})
 This target hook returns @code{false} if the @var{caller} function
 cannot inline @var{callee}, based on target specific information.  By
--- gcc/c-family/c-common.c.jj	2013-01-21 10:56:55.165014693 +0100
+++ gcc/c-family/c-common.c	2013-01-21 10:59:04.305285038 +0100
@@ -8759,12 +8759,8 @@ handle_target_attribute (tree *node, tre
       warning (OPT_Wattributes, "%qE attribute ignored", name);
       *no_add_attrs = true;
     }
-  /* Do not strip invalid target attributes for targets which support function
-     multiversioning as the target string is used to determine versioned
-     functions.  */
   else if (! targetm.target_option.valid_attribute_p (*node, name, args,
-						      flags)
-	   && ! targetm.target_option.supports_function_versions ())
+						      flags))
     *no_add_attrs = true;
 
   return NULL_TREE;
--- gcc/testsuite/g++.dg/mv1.C.jj	2013-01-21 10:56:54.564017815 +0100
+++ gcc/testsuite/g++.dg/mv1.C	2013-01-21 11:35:42.260684508 +0100
@@ -1,130 +0,0 @@
-/* Test case to check if Multiversioning works.  */
-/* { dg-do run { target i?86-*-* x86_64-*-* } } */
-/* { dg-require-ifunc "" }  */
-/* { dg-options "-O2 -fPIC" } */
-
-#include <assert.h>
-
-/* Default version.  */
-int foo ();
-/* The other versions of foo.  Mix up the ordering and 
-   check if the dispatching does it in the order of priority. */
-/* Check combination of target attributes.  */
-int foo () __attribute__ ((target("arch=corei7,popcnt")));
-/* The target operands in this declaration and the definition are re-ordered.
-   This should still work.  */
-int foo () __attribute__ ((target("ssse3,avx2")));
-
-/* Check for all target attributes for which dispatchers are available.  */
-/* Check arch= */
-int foo () __attribute__((target("arch=core2")));
-int foo () __attribute__((target("arch=corei7")));
-int foo () __attribute__((target("arch=atom")));
-/* Check ISAs  */
-int foo () __attribute__((target("avx")));
-int foo () __attribute__ ((target("arch=core2,sse4.2")));
-/* Check more arch=.  */
-int foo () __attribute__((target("arch=amdfam10")));
-int foo () __attribute__((target("arch=bdver1")));
-int foo () __attribute__((target("arch=bdver2")));
-
-int (*p)() = &foo;
-int main ()
-{
-  int val = foo ();
-  assert (val ==  (*p)());
-
-  /* Check in the exact same order in which the dispatching
-     is expected to happen.  */
-  if (__builtin_cpu_is ("bdver1"))
-    assert (val == 1);
-  else if (__builtin_cpu_is ("bdver2"))
-    assert (val == 2);
-  else if (__builtin_cpu_supports ("avx2")
-	   && __builtin_cpu_supports ("ssse3"))
-    assert (val == 3);
-  else if (__builtin_cpu_supports ("avx"))
-    assert (val == 4);
-  else if (__builtin_cpu_is ("corei7")
-	   && __builtin_cpu_supports ("popcnt"))
-    assert (val == 5);
-  else if (__builtin_cpu_is ("corei7"))
-    assert (val == 6);
-  else if (__builtin_cpu_is ("amdfam10h"))
-    assert (val == 7);
-  else if (__builtin_cpu_is ("core2")
-	   && __builtin_cpu_supports ("sse4.2"))
-    assert (val == 8);
-  else if (__builtin_cpu_is ("core2"))
-    assert (val == 9);
-  else if (__builtin_cpu_is ("atom"))
-    assert (val == 10);
-  else
-    assert (val == 0);
-  
-  return 0;
-}
-
-int foo ()
-{
-  return 0;
-}
-
-int __attribute__ ((target("arch=corei7,popcnt")))
-foo ()
-{
-  return 5;
-}
-int __attribute__ ((target("avx2,ssse3")))
-foo ()
-{
-  return 3;
-}
-
-int __attribute__ ((target("arch=core2")))
-foo ()
-{
-  return 9;
-}
-
-int __attribute__ ((target("arch=corei7")))
-foo ()
-{
-  return 6;
-}
-
-int __attribute__ ((target("arch=atom")))
-foo ()
-{
-  return 10;
-}
-
-int __attribute__ ((target("avx")))
-foo ()
-{
-  return 4;
-}
-
-int __attribute__ ((target("arch=core2,sse4.2")))
-foo ()
-{
-  return 8;
-}
-
-int __attribute__ ((target("arch=amdfam10")))
-foo ()
-{
-  return 7;
-}
-
-int __attribute__ ((target("arch=bdver1")))
-foo ()
-{
-  return 1;
-}
-
-int __attribute__ ((target("arch=bdver2")))
-foo ()
-{
-  return 2;
-}
--- gcc/testsuite/g++.dg/ext/mv1.C.jj	2013-01-21 11:36:16.084491175 +0100
+++ gcc/testsuite/g++.dg/ext/mv1.C	2013-01-21 11:42:52.975315718 +0100
@@ -0,0 +1,132 @@
+/* Test case to check if Multiversioning works.  */
+/* { dg-do run { target i?86-*-* x86_64-*-* } } */
+/* { dg-require-ifunc "" }  */
+/* { dg-options "-O2 -fPIC" } */
+
+#include <assert.h>
+
+/* Default version.  */
+int foo (); // Extra declaration that is merged with the second one.
+int foo () __attribute__ ((target("default")));
+/* The other versions of foo.  Mix up the ordering and 
+   check if the dispatching does it in the order of priority. */
+/* Check combination of target attributes.  */
+int foo () __attribute__ ((target("arch=corei7,popcnt")));
+/* The target operands in this declaration and the definition are re-ordered.
+   This should still work.  */
+int foo () __attribute__ ((target("ssse3,avx2")));
+
+/* Check for all target attributes for which dispatchers are available.  */
+/* Check arch= */
+int foo () __attribute__((target("arch=core2")));
+int foo () __attribute__((target("arch=corei7")));
+int foo () __attribute__((target("arch=atom")));
+/* Check ISAs  */
+int foo () __attribute__((target("avx")));
+int foo () __attribute__ ((target("arch=core2,sse4.2")));
+/* Check more arch=.  */
+int foo () __attribute__((target("arch=amdfam10")));
+int foo () __attribute__((target("arch=bdver1")));
+int foo () __attribute__((target("arch=bdver2")));
+
+int (*p)() = &foo;
+int main ()
+{
+  int val = foo ();
+  assert (val ==  (*p)());
+
+  /* Check in the exact same order in which the dispatching
+     is expected to happen.  */
+  if (__builtin_cpu_is ("bdver1"))
+    assert (val == 1);
+  else if (__builtin_cpu_is ("bdver2"))
+    assert (val == 2);
+  else if (__builtin_cpu_supports ("avx2")
+	   && __builtin_cpu_supports ("ssse3"))
+    assert (val == 3);
+  else if (__builtin_cpu_supports ("avx"))
+    assert (val == 4);
+  else if (__builtin_cpu_is ("corei7")
+	   && __builtin_cpu_supports ("popcnt"))
+    assert (val == 5);
+  else if (__builtin_cpu_is ("corei7"))
+    assert (val == 6);
+  else if (__builtin_cpu_is ("amdfam10h"))
+    assert (val == 7);
+  else if (__builtin_cpu_is ("core2")
+	   && __builtin_cpu_supports ("sse4.2"))
+    assert (val == 8);
+  else if (__builtin_cpu_is ("core2"))
+    assert (val == 9);
+  else if (__builtin_cpu_is ("atom"))
+    assert (val == 10);
+  else
+    assert (val == 0);
+  
+  return 0;
+}
+
+int __attribute__ ((target("default")))
+foo ()
+{
+  return 0;
+}
+
+int __attribute__ ((target("arch=corei7,popcnt")))
+foo ()
+{
+  return 5;
+}
+int __attribute__ ((target("avx2,ssse3")))
+foo ()
+{
+  return 3;
+}
+
+int __attribute__ ((target("arch=core2")))
+foo ()
+{
+  return 9;
+}
+
+int __attribute__ ((target("arch=corei7")))
+foo ()
+{
+  return 6;
+}
+
+int __attribute__ ((target("arch=atom")))
+foo ()
+{
+  return 10;
+}
+
+int __attribute__ ((target("avx")))
+foo ()
+{
+  return 4;
+}
+
+int __attribute__ ((target("arch=core2,sse4.2")))
+foo ()
+{
+  return 8;
+}
+
+int __attribute__ ((target("arch=amdfam10")))
+foo ()
+{
+  return 7;
+}
+
+int __attribute__ ((target("arch=bdver1")))
+foo ()
+{
+  return 1;
+}
+
+int __attribute__ ((target("arch=bdver2")))
+foo ()
+{
+  return 2;
+}
--- gcc/testsuite/g++.dg/mv2.C.jj	2013-01-21 10:56:54.465018354 +0100
+++ gcc/testsuite/g++.dg/mv2.C	2013-01-21 11:35:45.088666745 +0100
@@ -1,118 +0,0 @@
-/* Test case to check if Multiversioning chooses the correct
-   dispatching order when versions are for various ISAs.  */
-/* { dg-do run { target i?86-*-* x86_64-*-* } } */
-/* { dg-require-ifunc "" }  */
-/* { dg-options "-O2" } */
-
-#include <assert.h>
-
-/* Default version.  */
-int foo ();
-/* The dispatch checks should be in the exact reverse order of the
-   declarations below.  */
-int foo () __attribute__ ((target ("mmx")));
-int foo () __attribute__ ((target ("sse")));
-int foo () __attribute__ ((target ("sse2")));
-int foo () __attribute__ ((target ("sse3")));
-int foo () __attribute__ ((target ("ssse3")));
-int foo () __attribute__ ((target ("sse4.1")));
-int foo () __attribute__ ((target ("sse4.2")));
-int foo () __attribute__ ((target ("popcnt")));
-int foo () __attribute__ ((target ("avx")));
-int foo () __attribute__ ((target ("avx2")));
-
-int main ()
-{
-  int val = foo ();
-
-  if (__builtin_cpu_supports ("avx2"))
-    assert (val == 1);
-  else if (__builtin_cpu_supports ("avx"))
-    assert (val == 2);
-  else if (__builtin_cpu_supports ("popcnt"))
-    assert (val == 3);
-  else if (__builtin_cpu_supports ("sse4.2"))
-    assert (val == 4);
-  else if (__builtin_cpu_supports ("sse4.1"))
-    assert (val == 5);
-  else if (__builtin_cpu_supports ("ssse3"))
-    assert (val == 6);
-  else if (__builtin_cpu_supports ("sse3"))
-    assert (val == 7);
-  else if (__builtin_cpu_supports ("sse2"))
-    assert (val == 8);
-  else if (__builtin_cpu_supports ("sse"))
-    assert (val == 9);
-  else if (__builtin_cpu_supports ("mmx"))
-    assert (val == 10);
-  else
-    assert (val == 0);
-
-  return 0;
-}
-
-int
-foo ()
-{
-  return 0;
-}
-
-int __attribute__ ((target("mmx")))
-foo ()
-{
-  return 10;
-}
-
-int __attribute__ ((target("sse")))
-foo ()
-{
-  return 9;
-}
-
-int __attribute__ ((target("sse2")))
-foo ()
-{
-  return 8;
-}
-
-int __attribute__ ((target("sse3")))
-foo ()
-{
-  return 7;
-}
-
-int __attribute__ ((target("ssse3")))
-foo ()
-{
-  return 6;
-}
-
-int __attribute__ ((target("sse4.1")))
-foo ()
-{
-  return 5;
-}
-
-int __attribute__ ((target("sse4.2")))
-foo ()
-{
-  return 4;
-}
-
-int __attribute__ ((target("popcnt")))
-foo ()
-{
-  return 3;
-}
-
-int __attribute__ ((target("avx")))
-foo ()
-{
-  return 2;
-}
-
-int __attribute__ ((target("avx2")))
-foo ()
-{
-  return 1;
-}
--- gcc/testsuite/g++.dg/ext/mv2.C.jj	2013-01-21 11:36:16.085491165 +0100
+++ gcc/testsuite/g++.dg/ext/mv2.C	2013-01-21 10:58:57.000000000 +0100
@@ -0,0 +1,118 @@
+/* Test case to check if Multiversioning chooses the correct
+   dispatching order when versions are for various ISAs.  */
+/* { dg-do run { target i?86-*-* x86_64-*-* } } */
+/* { dg-require-ifunc "" }  */
+/* { dg-options "-O2" } */
+
+#include <assert.h>
+
+/* Default version.  */
+int foo () __attribute__ ((target ("default")));
+/* The dispatch checks should be in the exact reverse order of the
+   declarations below.  */
+int foo () __attribute__ ((target ("mmx")));
+int foo () __attribute__ ((target ("sse")));
+int foo () __attribute__ ((target ("sse2")));
+int foo () __attribute__ ((target ("sse3")));
+int foo () __attribute__ ((target ("ssse3")));
+int foo () __attribute__ ((target ("sse4.1")));
+int foo () __attribute__ ((target ("sse4.2")));
+int foo () __attribute__ ((target ("popcnt")));
+int foo () __attribute__ ((target ("avx")));
+int foo () __attribute__ ((target ("avx2")));
+
+int main ()
+{
+  int val = foo ();
+
+  if (__builtin_cpu_supports ("avx2"))
+    assert (val == 1);
+  else if (__builtin_cpu_supports ("avx"))
+    assert (val == 2);
+  else if (__builtin_cpu_supports ("popcnt"))
+    assert (val == 3);
+  else if (__builtin_cpu_supports ("sse4.2"))
+    assert (val == 4);
+  else if (__builtin_cpu_supports ("sse4.1"))
+    assert (val == 5);
+  else if (__builtin_cpu_supports ("ssse3"))
+    assert (val == 6);
+  else if (__builtin_cpu_supports ("sse3"))
+    assert (val == 7);
+  else if (__builtin_cpu_supports ("sse2"))
+    assert (val == 8);
+  else if (__builtin_cpu_supports ("sse"))
+    assert (val == 9);
+  else if (__builtin_cpu_supports ("mmx"))
+    assert (val == 10);
+  else
+    assert (val == 0);
+
+  return 0;
+}
+
+int __attribute__ ((target("default")))
+foo ()
+{
+  return 0;
+}
+
+int __attribute__ ((target("mmx")))
+foo ()
+{
+  return 10;
+}
+
+int __attribute__ ((target("sse")))
+foo ()
+{
+  return 9;
+}
+
+int __attribute__ ((target("sse2")))
+foo ()
+{
+  return 8;
+}
+
+int __attribute__ ((target("sse3")))
+foo ()
+{
+  return 7;
+}
+
+int __attribute__ ((target("ssse3")))
+foo ()
+{
+  return 6;
+}
+
+int __attribute__ ((target("sse4.1")))
+foo ()
+{
+  return 5;
+}
+
+int __attribute__ ((target("sse4.2")))
+foo ()
+{
+  return 4;
+}
+
+int __attribute__ ((target("popcnt")))
+foo ()
+{
+  return 3;
+}
+
+int __attribute__ ((target("avx")))
+foo ()
+{
+  return 2;
+}
+
+int __attribute__ ((target("avx2")))
+foo ()
+{
+  return 1;
+}
--- gcc/testsuite/g++.dg/mv3.C.jj	2013-01-18 21:23:45.000000000 +0100
+++ gcc/testsuite/g++.dg/mv3.C	2013-01-21 11:35:52.400626435 +0100
@@ -1,36 +0,0 @@
-/* Test case to check if a call to a multiversioned function
-   is replaced with a direct call to the particular version when
-   the most specialized version's target attributes match the
-   caller.  
-  
-   In this program, foo is multiversioned but there is no default
-   function.  This is an error if the call has to go through a
-   dispatcher.  However, the call to foo in bar can be replaced
-   with a direct call to the popcnt version of foo.  Hence, this
-   test should pass.  */
-
-/* { dg-do run { target i?86-*-* x86_64-*-* } } */
-/* { dg-options "-O2" } */
-
-
-int __attribute__ ((target ("sse")))
-foo ()
-{
-  return 1;
-}
-int __attribute__ ((target ("popcnt")))
-foo ()
-{
-  return 0;
-}
-
-int __attribute__ ((target ("popcnt")))
-bar ()
-{
-  return foo ();
-}
-
-int main ()
-{
-  return bar ();
-}
--- gcc/testsuite/g++.dg/ext/mv3.C.jj	2013-01-21 11:36:16.086491156 +0100
+++ gcc/testsuite/g++.dg/ext/mv3.C	2013-01-18 21:23:45.000000000 +0100
@@ -0,0 +1,36 @@
+/* Test case to check if a call to a multiversioned function
+   is replaced with a direct call to the particular version when
+   the most specialized version's target attributes match the
+   caller.  
+  
+   In this program, foo is multiversioned but there is no default
+   function.  This is an error if the call has to go through a
+   dispatcher.  However, the call to foo in bar can be replaced
+   with a direct call to the popcnt version of foo.  Hence, this
+   test should pass.  */
+
+/* { dg-do run { target i?86-*-* x86_64-*-* } } */
+/* { dg-options "-O2" } */
+
+
+int __attribute__ ((target ("sse")))
+foo ()
+{
+  return 1;
+}
+int __attribute__ ((target ("popcnt")))
+foo ()
+{
+  return 0;
+}
+
+int __attribute__ ((target ("popcnt")))
+bar ()
+{
+  return foo ();
+}
+
+int main ()
+{
+  return bar ();
+}
--- gcc/testsuite/g++.dg/mv4.C.jj	2013-01-18 21:23:45.000000000 +0100
+++ gcc/testsuite/g++.dg/mv4.C	2013-01-21 11:35:54.308616223 +0100
@@ -1,24 +0,0 @@
-/* Test case to check if the compiler generates an error message
-   when the default version of a multiversioned function is absent
-   and its pointer is taken.  */
-
-/* { dg-do compile { target i?86-*-* x86_64-*-* } } */
-/* { dg-require-ifunc "" }  */
-/* { dg-options "-O2" } */
-
-int __attribute__ ((target ("sse")))
-foo ()
-{
-  return 1;
-}
-int __attribute__ ((target ("popcnt")))
-foo ()
-{
-  return 0;
-}
-
-int main ()
-{
-  int (*p)() = &foo; /* { dg-error "use of multiversioned function without a default" {} } */
-  return (*p)();
-}
--- gcc/testsuite/g++.dg/ext/mv4.C.jj	2013-01-21 11:36:16.088491133 +0100
+++ gcc/testsuite/g++.dg/ext/mv4.C	2013-01-18 21:23:45.000000000 +0100
@@ -0,0 +1,24 @@
+/* Test case to check if the compiler generates an error message
+   when the default version of a multiversioned function is absent
+   and its pointer is taken.  */
+
+/* { dg-do compile { target i?86-*-* x86_64-*-* } } */
+/* { dg-require-ifunc "" }  */
+/* { dg-options "-O2" } */
+
+int __attribute__ ((target ("sse")))
+foo ()
+{
+  return 1;
+}
+int __attribute__ ((target ("popcnt")))
+foo ()
+{
+  return 0;
+}
+
+int main ()
+{
+  int (*p)() = &foo; /* { dg-error "use of multiversioned function without a default" {} } */
+  return (*p)();
+}
--- gcc/testsuite/g++.dg/mv5.C.jj	2013-01-21 10:56:54.582017723 +0100
+++ gcc/testsuite/g++.dg/mv5.C	2013-01-21 11:35:56.027606185 +0100
@@ -1,25 +0,0 @@
-/* Test case to check if multiversioned functions are still generated if they are
-   marked comdat with inline keyword.  */
-
-/* { dg-do run { target i?86-*-* x86_64-*-* } } */
-/* { dg-require-ifunc "" }  */
-/* { dg-options "-O2" } */
-
-
-/* Default version.  */
-inline int
-foo ()
-{
-  return 0;
-}
-
-inline int __attribute__ ((target ("popcnt")))
-foo ()
-{
-  return 0;
-}
-
-int main ()
-{
-  return foo ();
-}
--- gcc/testsuite/g++.dg/ext/mv5.C.jj	2013-01-21 11:36:16.089491123 +0100
+++ gcc/testsuite/g++.dg/ext/mv5.C	2013-01-21 10:58:57.000000000 +0100
@@ -0,0 +1,25 @@
+/* Test case to check if multiversioned functions are still generated if they are
+   marked comdat with inline keyword.  */
+
+/* { dg-do run { target i?86-*-* x86_64-*-* } } */
+/* { dg-require-ifunc "" }  */
+/* { dg-options "-O2" } */
+
+
+/* Default version.  */
+inline int __attribute__ ((target ("default")))
+foo ()
+{
+  return 0;
+}
+
+inline int __attribute__ ((target ("popcnt")))
+foo ()
+{
+  return 0;
+}
+
+int main ()
+{
+  return foo ();
+}
--- gcc/testsuite/g++.dg/mv6.C.jj	2013-01-21 10:56:54.504018081 +0100
+++ gcc/testsuite/g++.dg/mv6.C	2013-01-21 11:35:57.514597697 +0100
@@ -1,27 +0,0 @@
-/* Test to check if member version multiversioning works correctly.  */
-
-/* { dg-do run { target i?86-*-* x86_64-*-* } } */
-/* { dg-require-ifunc "" }  */
-/* { dg-options "-march=x86-64" } */
-
-class Foo
-{
- public:
-  /* Default version of foo.  */
-  int foo ()
-  {
-    return 0;
-  }
-  /* corei7 version of foo.  */
-  __attribute__ ((target("arch=corei7")))
-  int foo ()
-  {
-    return 0;
-  }
-};
-
-int main ()
-{
-  Foo f;
-  return f.foo ();
-}
--- gcc/testsuite/g++.dg/ext/mv6.C.jj	2013-01-21 11:36:16.090491117 +0100
+++ gcc/testsuite/g++.dg/ext/mv6.C	2013-01-21 10:58:57.000000000 +0100
@@ -0,0 +1,28 @@
+/* Test to check if member version multiversioning works correctly.  */
+
+/* { dg-do run { target i?86-*-* x86_64-*-* } } */
+/* { dg-require-ifunc "" }  */
+/* { dg-options "-march=x86-64" } */
+
+class Foo
+{
+ public:
+  /* Default version of foo.  */
+  __attribute__ ((target("default")))
+  int foo ()
+  {
+    return 0;
+  }
+  /* corei7 version of foo.  */
+  __attribute__ ((target("arch=corei7")))
+  int foo ()
+  {
+    return 0;
+  }
+};
+
+int main ()
+{
+  Foo f;
+  return f.foo ();
+}
--- gcc/testsuite/g++.dg/ext/mv7.C.jj	2013-01-21 11:39:21.789460493 +0100
+++ gcc/testsuite/g++.dg/ext/mv7.C	2013-01-21 11:45:05.098589632 +0100
@@ -0,0 +1,12 @@
+// { dg-do compile { target i?86-*-* x86_64-*-* } }
+// { dg-options "" }
+
+__attribute__((target ("default")))
+void foo (void)	// { dg-error "previously defined here" }
+{
+}
+
+__attribute__((target (128)))
+void foo (void) // { dg-error "(not a string|redefinition)" }
+{
+}
--- gcc/testsuite/g++.dg/ext/mv8.C.jj	2013-01-21 11:41:17.147836101 +0100
+++ gcc/testsuite/g++.dg/ext/mv8.C	2013-01-21 11:45:13.493544256 +0100
@@ -0,0 +1,7 @@
+// { dg-do compile { target i?86-*-* x86_64-*-* } }
+// { dg-options "" }
+
+__attribute__((target (11,12)))
+void foo (void) // { dg-error "not a string" }
+{
+}
--- gcc/testsuite/g++.dg/ext/mv9.C.jj	2013-01-21 11:44:31.634774921 +0100
+++ gcc/testsuite/g++.dg/ext/mv9.C	2013-01-21 11:45:18.275516266 +0100
@@ -0,0 +1,9 @@
+// { dg-do compile { target i?86-*-* x86_64-*-* } }    
+// { dg-options "" }   
+
+void foo ();
+void foo () __attribute__((target ("sse4")));
+void foo () __attribute__((target ("default"))); // { dg-error "previous declaration" }
+void foo ()	// { dg-error "attribute for multi-versioned" }
+{
+}
--- gcc/testsuite/g++.dg/ext/mv10.C.jj	2013-01-21 12:12:29.354541630 +0100
+++ gcc/testsuite/g++.dg/ext/mv10.C	2013-01-21 12:12:56.207392886 +0100
@@ -0,0 +1,12 @@
+// { dg-do assemble { target i?86-*-* x86_64-*-* } }
+// { dg-options "" }
+
+__attribute__((target ("popcnt"), used))
+void foo (void)
+{
+}
+
+__attribute__((target ("popcnt","avx"), used))
+void foo (void)
+{
+}
--- gcc/testsuite/g++.dg/ext/mv11.C.jj	2013-01-21 12:16:26.381285535 +0100
+++ gcc/testsuite/g++.dg/ext/mv11.C	2013-01-21 12:17:33.380918996 +0100
@@ -0,0 +1,23 @@
+// { dg-do compile { target i?86-*-* x86_64-*-* } }
+// { dg-options "-msse2" }
+
+int foo () __attribute__ ((target("default")));
+int foo () __attribute__ ((target("sse2")));
+
+int
+main ()
+{
+  return foo ();
+}
+
+int  __attribute__ ((target("default")))
+foo ()
+{
+  return 0;
+}
+
+int __attribute__ ((target("sse2")))
+foo ()
+{
+  return 0;
+}


	Jakub

Re: [PATCH] Multiversioning fixes (PR c++/55742, take 2)

[Jason Merrill]

OK.  Sriraman, are you working on documentation and more tests?

Jason

Re: [PATCH] Multiversioning fixes (PR c++/55742, take 2)

[Sriraman Tallam]

[-- Attachment #1: Type: text/plain, Size: 424 bytes --]

Hi,

  I have attached a patch documenting Function Multiversioning and
added a few more tests. I have also updated the wiki
http://gcc.gnu.org/wiki/FunctionMultiVersioning. Please let me know if
there are any more tests you specifically want.

  Please review.

Thanks
Sri

On Wed, Jan 30, 2013 at 5:55 AM, Jason Merrill <jason@redhat.com> wrote:
> OK.  Sriraman, are you working on documentation and more tests?
>
> Jason

[-- Attachment #2: mv.txt --]
[-- Type: text/plain, Size: 6900 bytes --]

	* doc/extend.texi: Document Function Multiversioning and "default"
	parameter string to target attribute.
	* g++.dg/ext/mv12.C: New test.
	* g++.dg/ext/mv13.C: New test.
	* g++.dg/ext/mv13.h: New file.
	* g++.dg/ext/mv13-aux.C: New file.
	* config/i386/i386.c (ix86_mangle_function_version_assembler_name): Change
	comment.
Index: gcc/doc/extend.texi
===================================================================
--- gcc/doc/extend.texi	(revision 195818)
+++ gcc/doc/extend.texi	(working copy)
@@ -3655,6 +3655,11 @@ Enable/disable the generation of the advanced bit
 @cindex @code{target("aes")} attribute
 Enable/disable the generation of the AES instructions.
 
+@item default
+@cindex @code{target("default")} attribute
+@xref{Function Multiversioning}, where it is used to specify the
+default function version.
+
 @item mmx
 @itemx no-mmx
 @cindex @code{target("mmx")} attribute
@@ -15215,6 +15220,7 @@ Predefined Macros,cpp,The GNU C Preprocessor}).
 * Bound member functions:: You can extract a function pointer to the
                         method denoted by a @samp{->*} or @samp{.*} expression.
 * C++ Attributes::      Variable, function, and type attributes for C++ only.
+* Function Multiversioning::   Declaring multiple function versions.
 * Namespace Association:: Strong using-directives for namespace association.
 * Type Traits::         Compiler support for type traits
 * Java Exceptions::     Tweaking exception handling to work with Java.
@@ -15744,6 +15750,64 @@ interface table mechanism, instead of regular virt
 
 See also @ref{Namespace Association}.
 
+@node Function Multiversioning
+@section Function Multiversioning
+@cindex function versions
+
+With the GNU C++ front end, for target i386, you may specify multiple
+versions of a function, where each function is specialized for a
+specific target feature.  At runtime, the appropriate version of the
+function is automatically executed depending on the characteristics of
+the execution platform.  Here is an example.
+
+@smallexample
+__attribute__ ((target ("default")))
+int foo ()
+@{
+  // The default version of foo.
+  return 0;
+@}
+
+__attribute__ ((target ("sse4.2")))
+int foo ()
+@{
+  // foo version for SSE4.2
+  return 1;
+@}
+
+__attribute__ ((target ("arch=atom")))
+int foo ()
+@{
+  // foo version for the Intel ATOM processor
+  return 2;
+@}
+
+__attribute__ ((target ("arch=amdfam10")))
+int foo ()
+@{
+  // foo version for the AMD Family 0x10 processors.
+  return 3;
+@}
+
+int main ()
+@{
+  int (*p)() = &foo;
+  assert ((*p) () == foo ());
+  return 0;
+@}
+@end smallexample
+
+In the above example, four versions of function foo are created. The
+first version of foo with the target attribute "default" is the default
+version.  This version gets executed when no other target specific
+version qualifies for execution on a particular platform. A new version
+of foo is created by using the same function signature but with a
+different target string.  Function foo is called or a pointer to it is
+taken just like a regular function.  GCC takes care of doing the
+dispatching to call the right version at runtime.  Refer to the
+@uref{http://gcc.gnu.org/wiki/FunctionMultiVersioning, GCC wiki on
+Function Multiversioning} for more details.
+
 @node Namespace Association
 @section Namespace Association
 
Index: gcc/testsuite/g++.dg/ext/mv13-aux.C
===================================================================
--- gcc/testsuite/g++.dg/ext/mv13-aux.C	(revision 0)
+++ gcc/testsuite/g++.dg/ext/mv13-aux.C	(revision 0)
@@ -0,0 +1,11 @@
+// Test case to check if multiversioning works as expected when the versions
+// are defined in different files. Auxiliary file for mv13.C.
+// { dg-do compile }
+
+#include "mv13.h"
+
+__attribute__ ((target ("sse4.2")))
+int foo ()
+{
+  return 1;
+}
Index: gcc/testsuite/g++.dg/ext/mv12.C
===================================================================
--- gcc/testsuite/g++.dg/ext/mv12.C	(revision 0)
+++ gcc/testsuite/g++.dg/ext/mv12.C	(revision 0)
@@ -0,0 +1,21 @@
+// Test to check if an error is generated when virtual functions
+// are multiversioned.  
+
+// { dg-do compile { target i?86-*-* x86_64-*-* } }
+// { dg-options "" }
+class Foo
+{
+ public:
+  /* Default version of foo.  */
+  __attribute__ ((target("default")))
+  virtual int foo () // { dg-error "Virtual function multiversioning not supported" }
+  {
+    return 0;
+  }
+  /* corei7 version of foo.  */
+  __attribute__ ((target("arch=corei7")))
+  virtual int foo () // { dg-error "Virtual function multiversioning not supported" }
+  {
+    return 0;
+  }
+};
Index: gcc/testsuite/g++.dg/ext/mv13.C
===================================================================
--- gcc/testsuite/g++.dg/ext/mv13.C	(revision 0)
+++ gcc/testsuite/g++.dg/ext/mv13.C	(revision 0)
@@ -0,0 +1,22 @@
+// Test case to check if multiversioning works as expected when the versions
+// are defined in different files.
+
+// { dg-do run { target i?86-*-* x86_64-*-* } }
+// { dg-require-ifunc "" }
+// { dg-options "-O2" }
+// { dg-additional-sources "mv13-aux.C" }
+
+#include "mv13.h"
+
+int main ()
+{
+  if (__builtin_cpu_supports ("sse4.2"))
+    return foo () - 1;
+  return foo ();
+}
+
+__attribute__ ((target ("default")))
+int foo ()
+{
+  return 0;
+}
Index: gcc/testsuite/g++.dg/ext/mv13.h
===================================================================
--- gcc/testsuite/g++.dg/ext/mv13.h	(revision 0)
+++ gcc/testsuite/g++.dg/ext/mv13.h	(revision 0)
@@ -0,0 +1,6 @@
+// Header file used by mv13.C and mv13-aux.C.
+// { dg-do compile { target i?86-*-* x86_64-*-* } }
+// { dg-options "" }
+
+int foo () __attribute__ ((target ("default")));
+int foo () __attribute__ ((target ("sse4.2")));
Index: gcc/testsuite/g++.dg/ext/mv14.C
===================================================================
--- gcc/testsuite/g++.dg/ext/mv14.C	(revision 0)
+++ gcc/testsuite/g++.dg/ext/mv14.C	(revision 0)
@@ -0,0 +1,18 @@
+// Test case to check if multiversioning functions that are extern "C"
+// generates errors.
+
+// { dg-do compile { target i?86-*-* x86_64-*-* } }
+
+extern "C"
+__attribute__ ((target ("default")))
+int foo ()  // { dg-error "previously defined here" }
+{
+  return 0;
+}
+
+extern "C"
+__attribute__ ((target ("sse4.2")))
+int foo () // { dg-error "redefinition" }
+{
+  return 1;
+}
Index: gcc/config/i386/i386.c
===================================================================
--- gcc/config/i386/i386.c	(revision 195818)
+++ gcc/config/i386/i386.c	(working copy)
@@ -29065,7 +29065,7 @@ ix86_mangle_function_version_assembler_name (tree
   if (DECL_VIRTUAL_P (decl)
       || DECL_VINDEX (decl))
     error_at (DECL_SOURCE_LOCATION (decl),
-	      "Virtual function versioning not supported\n");
+	      "Virtual function multiversioning not supported\n");
 
   version_attr = lookup_attribute ("target", DECL_ATTRIBUTES (decl));
 

Re: [PATCH] Multiversioning fixes (PR c++/55742, take 2)

[Jason Merrill]

On 02/06/2013 08:39 PM, Sriraman Tallam wrote:
> +// Test to check if an error is generated when virtual functions
> +// are multiversioned.

This seems like a TODO, rather than something to test for.  I don't see 
any reason why we couldn't support multiversioned virtual functions.

>      error_at (DECL_SOURCE_LOCATION (decl),
> -	      "Virtual function versioning not supported\n");
> +	      "Virtual function multiversioning not supported\n");

And so this should be a sorry rather than an error.

Jason

Re: [PATCH] Multiversioning fixes (PR c++/55742, take 2)

[Sriraman Tallam]

[-- Attachment #1: Type: text/plain, Size: 730 bytes --]

On Thu, Feb 7, 2013 at 6:29 AM, Jason Merrill <jason@redhat.com> wrote:
> On 02/06/2013 08:39 PM, Sriraman Tallam wrote:
>>
>> +// Test to check if an error is generated when virtual functions
>> +// are multiversioned.
>
>
> This seems like a TODO, rather than something to test for.  I don't see any
> reason why we couldn't support multiversioned virtual functions.
>
>>      error_at (DECL_SOURCE_LOCATION (decl),
>> -             "Virtual function versioning not supported\n");
>> +             "Virtual function multiversioning not supported\n");
>
>
> And so this should be a sorry rather than an error.

Attached a new patch with these changes. Also made more minor changes
to config/i386/i386.c.

Thanks
Sri

>
> Jason
>

[-- Attachment #2: mv.txt --]
[-- Type: text/plain, Size: 8214 bytes --]

	* doc/extend.texi: Document Function Multiversioning and "default"
	parameter string to target attribute.
	* g++.dg/ext/mv12.C: New test.
	* g++.dg/ext/mv12.h: New file.
	* g++.dg/ext/mv12-aux.C: New file.
	* g++.dg/ext/mv13.C: New test.
	* config/i386/i386.c (get_builtin_code_for_version): Return 0 if
	target attribute parameter is "default".
	(ix86_compare_version_priority): Remove checks for target attribute.
	(ix86_mangle_function_version_assembler_name): Change error to sorry.
	Remove check for target attribute equal to NULL. Add assert.
	(ix86_generate_version_dispatcher_body): Change error to sorry.

Index: gcc/doc/extend.texi
===================================================================
--- gcc/doc/extend.texi	(revision 195818)
+++ gcc/doc/extend.texi	(working copy)
@@ -3655,6 +3655,11 @@ Enable/disable the generation of the advanced bit
 @cindex @code{target("aes")} attribute
 Enable/disable the generation of the AES instructions.
 
+@item default
+@cindex @code{target("default")} attribute
+@xref{Function Multiversioning}, where it is used to specify the
+default function version.
+
 @item mmx
 @itemx no-mmx
 @cindex @code{target("mmx")} attribute
@@ -15215,6 +15220,7 @@ Predefined Macros,cpp,The GNU C Preprocessor}).
 * Bound member functions:: You can extract a function pointer to the
                         method denoted by a @samp{->*} or @samp{.*} expression.
 * C++ Attributes::      Variable, function, and type attributes for C++ only.
+* Function Multiversioning::   Declaring multiple function versions.
 * Namespace Association:: Strong using-directives for namespace association.
 * Type Traits::         Compiler support for type traits
 * Java Exceptions::     Tweaking exception handling to work with Java.
@@ -15744,6 +15750,64 @@ interface table mechanism, instead of regular virt
 
 See also @ref{Namespace Association}.
 
+@node Function Multiversioning
+@section Function Multiversioning
+@cindex function versions
+
+With the GNU C++ front end, for target i386, you may specify multiple
+versions of a function, where each function is specialized for a
+specific target feature.  At runtime, the appropriate version of the
+function is automatically executed depending on the characteristics of
+the execution platform.  Here is an example.
+
+@smallexample
+__attribute__ ((target ("default")))
+int foo ()
+@{
+  // The default version of foo.
+  return 0;
+@}
+
+__attribute__ ((target ("sse4.2")))
+int foo ()
+@{
+  // foo version for SSE4.2
+  return 1;
+@}
+
+__attribute__ ((target ("arch=atom")))
+int foo ()
+@{
+  // foo version for the Intel ATOM processor
+  return 2;
+@}
+
+__attribute__ ((target ("arch=amdfam10")))
+int foo ()
+@{
+  // foo version for the AMD Family 0x10 processors.
+  return 3;
+@}
+
+int main ()
+@{
+  int (*p)() = &foo;
+  assert ((*p) () == foo ());
+  return 0;
+@}
+@end smallexample
+
+In the above example, four versions of function foo are created. The
+first version of foo with the target attribute "default" is the default
+version.  This version gets executed when no other target specific
+version qualifies for execution on a particular platform. A new version
+of foo is created by using the same function signature but with a
+different target string.  Function foo is called or a pointer to it is
+taken just like a regular function.  GCC takes care of doing the
+dispatching to call the right version at runtime.  Refer to the
+@uref{http://gcc.gnu.org/wiki/FunctionMultiVersioning, GCC wiki on
+Function Multiversioning} for more details.
+
 @node Namespace Association
 @section Namespace Association
 
Index: gcc/testsuite/g++.dg/ext/mv12-aux.C
===================================================================
--- gcc/testsuite/g++.dg/ext/mv12-aux.C	(revision 0)
+++ gcc/testsuite/g++.dg/ext/mv12-aux.C	(revision 0)
@@ -0,0 +1,11 @@
+// Test case to check if multiversioning works as expected when the versions
+// are defined in different files. Auxiliary file for mv12.C.
+// { dg-do compile }
+
+#include "mv12.h"
+
+__attribute__ ((target ("sse4.2")))
+int foo ()
+{
+  return 1;
+}
Index: gcc/testsuite/g++.dg/ext/mv12.C
===================================================================
--- gcc/testsuite/g++.dg/ext/mv12.C	(revision 0)
+++ gcc/testsuite/g++.dg/ext/mv12.C	(revision 0)
@@ -0,0 +1,22 @@
+// Test case to check if multiversioning works as expected when the versions
+// are defined in different files.
+
+// { dg-do run { target i?86-*-* x86_64-*-* } }
+// { dg-require-ifunc "" }
+// { dg-options "-O2" }
+// { dg-additional-sources "mv12-aux.C" }
+
+#include "mv12.h"
+
+int main ()
+{
+  if (__builtin_cpu_supports ("sse4.2"))
+    return foo () - 1;
+  return foo ();
+}
+
+__attribute__ ((target ("default")))
+int foo ()
+{
+  return 0;
+}
Index: gcc/testsuite/g++.dg/ext/mv12.h
===================================================================
--- gcc/testsuite/g++.dg/ext/mv12.h	(revision 0)
+++ gcc/testsuite/g++.dg/ext/mv12.h	(revision 0)
@@ -0,0 +1,6 @@
+// Header file used by mv12.C and mv12-aux.C.
+// { dg-do compile { target i?86-*-* x86_64-*-* } }
+// { dg-options "" }
+
+int foo () __attribute__ ((target ("default")));
+int foo () __attribute__ ((target ("sse4.2")));
Index: gcc/testsuite/g++.dg/ext/mv13.C
===================================================================
--- gcc/testsuite/g++.dg/ext/mv13.C	(revision 0)
+++ gcc/testsuite/g++.dg/ext/mv13.C	(revision 0)
@@ -0,0 +1,18 @@
+// Test case to check if multiversioning functions that are extern "C"
+// generates errors.
+
+// { dg-do compile { target i?86-*-* x86_64-*-* } }
+
+extern "C"
+__attribute__ ((target ("default")))
+int foo ()  // { dg-error "previously defined here" }
+{
+  return 0;
+}
+
+extern "C"
+__attribute__ ((target ("sse4.2")))
+int foo () // { dg-error "redefinition" }
+{
+  return 1;
+}
Index: gcc/config/i386/i386.c
===================================================================
--- gcc/config/i386/i386.c	(revision 195818)
+++ gcc/config/i386/i386.c	(working copy)
@@ -28695,6 +28695,9 @@ get_builtin_code_for_version (tree decl, tree *pre
   gcc_assert (TREE_CODE (attrs) == STRING_CST);
   attrs_str = TREE_STRING_POINTER (attrs);
 
+  /* Return priority zero for default function.  */
+  if (strcmp (attrs_str, "default") == 0)
+    return 0;
 
   /* Handle arch= if specified.  For priority, set it to be 1 more than
      the best instruction set the processor can handle.  For instance, if
@@ -28827,15 +28830,9 @@ get_builtin_code_for_version (tree decl, tree *pre
 static int
 ix86_compare_version_priority (tree decl1, tree decl2)
 {
-  unsigned int priority1 = 0;
-  unsigned int priority2 = 0;
+  unsigned int priority1 = get_builtin_code_for_version (decl1, NULL);
+  unsigned int priority2 = get_builtin_code_for_version (decl2, NULL);
 
-  if (lookup_attribute ("target", DECL_ATTRIBUTES (decl1)) != NULL)
-    priority1 = get_builtin_code_for_version (decl1, NULL);
-
-  if (lookup_attribute ("target", DECL_ATTRIBUTES (decl2)) != NULL)
-    priority2 = get_builtin_code_for_version (decl2, NULL);
-
   return (int)priority1 - (int)priority2;
 }
 
@@ -29064,14 +29061,12 @@ ix86_mangle_function_version_assembler_name (tree
 
   if (DECL_VIRTUAL_P (decl)
       || DECL_VINDEX (decl))
-    error_at (DECL_SOURCE_LOCATION (decl),
-	      "Virtual function versioning not supported\n");
+    sorry ("Virtual function multiversioning not supported");
 
   version_attr = lookup_attribute ("target", DECL_ATTRIBUTES (decl));
 
-  /* target attribute string is NULL for default functions.  */
-  if (version_attr == NULL_TREE)
-    return id;
+  /* target attribute string cannot be NULL.  */
+  gcc_assert (version_attr != NULL_TREE);
 
   orig_name = IDENTIFIER_POINTER (id);
   version_string
@@ -29511,8 +29506,8 @@ ix86_generate_version_dispatcher_body (void *node_
 	 virtual methods in base classes but are not explicitly marked as
 	 virtual.  */
       if (DECL_VINDEX (versn->symbol.decl))
-        error_at (DECL_SOURCE_LOCATION (versn->symbol.decl),
-		  "Virtual function multiversioning not supported");
+	sorry ("Virtual function multiversioning not supported");
+
       fn_ver_vec.safe_push (versn->symbol.decl);
     }
 

Re: [PATCH] Multiversioning fixes (PR c++/55742, take 2)

[Sriraman Tallam]

Hi,

  Is this alright to commit?

Thanks
Sri

On Thu, Feb 7, 2013 at 4:10 PM, Sriraman Tallam <tmsriram@google.com> wrote:
> On Thu, Feb 7, 2013 at 6:29 AM, Jason Merrill <jason@redhat.com> wrote:
>> On 02/06/2013 08:39 PM, Sriraman Tallam wrote:
>>>
>>> +// Test to check if an error is generated when virtual functions
>>> +// are multiversioned.
>>
>>
>> This seems like a TODO, rather than something to test for.  I don't see any
>> reason why we couldn't support multiversioned virtual functions.
>>
>>>      error_at (DECL_SOURCE_LOCATION (decl),
>>> -             "Virtual function versioning not supported\n");
>>> +             "Virtual function multiversioning not supported\n");
>>
>>
>> And so this should be a sorry rather than an error.
>
> Attached a new patch with these changes. Also made more minor changes
> to config/i386/i386.c.
>
> Thanks
> Sri
>
>>
>> Jason
>>

Re: [PATCH] Multiversioning fixes (PR c++/55742, take 2)

[Jason Merrill]

OK, thanks.

Jason

Re: [PATCH] Multiversioning fixes (PR c++/55742, take 2)

[Andreas Schwab]

Sriraman Tallam <tmsriram@google.com> writes:

> Index: gcc/testsuite/g++.dg/ext/mv12-aux.C
> ===================================================================
> --- gcc/testsuite/g++.dg/ext/mv12-aux.C	(revision 0)
> +++ gcc/testsuite/g++.dg/ext/mv12-aux.C	(revision 0)
> @@ -0,0 +1,11 @@
> +// Test case to check if multiversioning works as expected when the versions
> +// are defined in different files. Auxiliary file for mv12.C.
> +// { dg-do compile }
> +
> +#include "mv12.h"
> +
> +__attribute__ ((target ("sse4.2")))
> +int foo ()

FAIL: g++.dg/ext/mv12-aux.C -std=c++11 (test for excess errors)
Excess errors:
/daten/aranym/gcc/gcc-20130213/gcc/testsuite/g++.dg/ext/mv12.h:5:47: warning: target attribute is not supported on this machine [-Wattributes]
/daten/aranym/gcc/gcc-20130213/gcc/testsuite/g++.dg/ext/mv12.h:6:46: warning: target attribute is not supported on this machine [-Wattributes]
/daten/aranym/gcc/gcc-20130213/gcc/testsuite/g++.dg/ext/mv12-aux.C:8:10: warning: target attribute is not supported on this machine [-Wattributes]

Andreas.

-- 
Andreas Schwab, SUSE Labs, schwab@suse.de
GPG Key fingerprint = 0196 BAD8 1CE9 1970 F4BE  1748 E4D4 88E3 0EEA B9D7
"And now for something completely different."

Re: [PATCH] Multiversioning fixes (PR c++/55742, take 2)

[Sriraman Tallam]

On Wed, Feb 13, 2013 at 7:46 AM, Sriraman Tallam <tmsriram@google.com> wrote:
>
> On Feb 13, 2013 1:21 AM, "Andreas Schwab" <schwab@suse.de> wrote:
>>
>> Sriraman Tallam <tmsriram@google.com> writes:
>>
>> > Index: gcc/testsuite/g++.dg/ext/mv12-aux.C
>> > ===================================================================
>> > --- gcc/testsuite/g++.dg/ext/mv12-aux.C       (revision 0)
>> > +++ gcc/testsuite/g++.dg/ext/mv12-aux.C       (revision 0)
>> > @@ -0,0 +1,11 @@
>> > +// Test case to check if multiversioning works as expected when the
>> > versions
>> > +// are defined in different files. Auxiliary file for mv12.C.
>> > +// { dg-do compile }
>> > +
>> > +#include "mv12.h"
>> > +
>> > +__attribute__ ((target ("sse4.2")))
>> > +int foo ()
>>
>> FAIL: g++.dg/ext/mv12-aux.C -std=c++11 (test for excess errors)
>> Excess errors:
>> /daten/aranym/gcc/gcc-20130213/gcc/testsuite/g++.dg/ext/mv12.h:5:47:
>> warning: target attribute is not supported on this machine [-Wattributes]
>> /daten/aranym/gcc/gcc-20130213/gcc/testsuite/g++.dg/ext/mv12.h:6:46:
>> warning: target attribute is not supported on this machine [-Wattributes]
>> /daten/aranym/gcc/gcc-20130213/gcc/testsuite/g++.dg/ext/mv12-aux.C:8:10:
>> warning: target attribute is not supported on this machine [-Wattributes]
>
> I will fix this asap. Sorry about this.

I committed a trivial patch to fix this problem. mv12-aux.C is
auxiliary to mv12.C and should have the same test directives as
mv12.C.

2013-02-13  Sriraman Tallam  <tmsriram@google.com>

        * g++.dg/ext/mv12-aux.C: Add directives to match mv12.C.


Index: g++.dg/ext/mv12-aux.C
===================================================================
--- g++.dg/ext/mv12-aux.C (revision 196025)
+++ g++.dg/ext/mv12-aux.C (working copy)
@@ -1,7 +1,10 @@
 // Test case to check if multiversioning works as expected when the versions
 // are defined in different files. Auxiliary file for mv12.C.
-// { dg-do compile }

+// { dg-do compile { target i?86-*-* x86_64-*-* } }
+// { dg-require-ifunc "" }
+// { dg-options "-O2" }
+
 #include "mv12.h"

This should fix the problem.

Thanks
Sri


>
> Sri
>
>>
>> Andreas.
>>
>> --
>> Andreas Schwab, SUSE Labs, schwab@suse.de
>> GPG Key fingerprint = 0196 BAD8 1CE9 1970 F4BE  1748 E4D4 88E3 0EEA B9D7
>> "And now for something completely different."

Re: [PATCH] Multiversioning fixes (PR c++/55742, take 2)

[Jakub Jelinek]

On Wed, Feb 13, 2013 at 10:57:42AM -0800, Sriraman Tallam wrote:
> I committed a trivial patch to fix this problem. mv12-aux.C is
> auxiliary to mv12.C and should have the same test directives as
> mv12.C.
> 
> 2013-02-13  Sriraman Tallam  <tmsriram@google.com>
> 
>         * g++.dg/ext/mv12-aux.C: Add directives to match mv12.C.

Better would be to rename
g++.dg/ext/mv12-aux.C to g++.dg/ext/mv12-aux.cc and remove all dg-*
directives from it, plus adjust dg-additional-sources in mv12.C.
The dg.exp driver is only looking for *.C testcases, so it will skip
*.cc, which is what you want.

> --- g++.dg/ext/mv12-aux.C (revision 196025)
> +++ g++.dg/ext/mv12-aux.C (working copy)
> @@ -1,7 +1,10 @@
>  // Test case to check if multiversioning works as expected when the versions
>  // are defined in different files. Auxiliary file for mv12.C.
> -// { dg-do compile }
> 
> +// { dg-do compile { target i?86-*-* x86_64-*-* } }
> +// { dg-require-ifunc "" }
> +// { dg-options "-O2" }
> +
>  #include "mv12.h"
> 
> This should fix the problem.

	Jakub

Re: [PATCH] Multiversioning fixes (PR c++/55742, take 2)

[Sriraman Tallam]

On Wed, Feb 13, 2013 at 12:14 PM, Jakub Jelinek <jakub@redhat.com> wrote:
> On Wed, Feb 13, 2013 at 10:57:42AM -0800, Sriraman Tallam wrote:
>> I committed a trivial patch to fix this problem. mv12-aux.C is
>> auxiliary to mv12.C and should have the same test directives as
>> mv12.C.
>>
>> 2013-02-13  Sriraman Tallam  <tmsriram@google.com>
>>
>>         * g++.dg/ext/mv12-aux.C: Add directives to match mv12.C.
>
> Better would be to rename
> g++.dg/ext/mv12-aux.C to g++.dg/ext/mv12-aux.cc and remove all dg-*
> directives from it, plus adjust dg-additional-sources in mv12.C.
> The dg.exp driver is only looking for *.C testcases, so it will skip
> *.cc, which is what you want.

Committed patch which does exactly this.

2013-02-13  Sriraman Tallam  <tmsriram@google.com>

        * g++.dg/ext/mv12-aux.C: Delete, move to mv12-aux.cc.
        * g++.dg/ext/mv12-aux.cc: New file.
        * g++.dg/ext/mv12.h: Remove directives. Fix comment.
        * g++.dg/ext/mv12.C: Fix file name.

Index: mv12-aux.cc
===================================================================
--- mv12-aux.cc (revision 0)
+++ mv12-aux.cc (revision 0)
@@ -0,0 +1,10 @@
+// Test case to check if multiversioning works as expected when the versions
+// are defined in different files. Auxiliary file for mv12.C.
+
+#include "mv12.h"
+
+__attribute__ ((target ("sse4.2")))
+int foo ()
+{
+  return 1;
+}
Index: mv12.C
===================================================================
--- mv12.C (revision 196025)
+++ mv12.C (working copy)
@@ -4,7 +4,7 @@
 // { dg-do run { target i?86-*-* x86_64-*-* } }
 // { dg-require-ifunc "" }
 // { dg-options "-O2" }
-// { dg-additional-sources "mv12-aux.C" }
+// { dg-additional-sources "mv12-aux.cc" }

 #include "mv12.h"

Index: mv12.h
===================================================================
--- mv12.h (revision 196025)
+++ mv12.h (working copy)
@@ -1,6 +1,4 @@
-// Header file used by mv12.C and mv12-aux.C.
-// { dg-do compile { target i?86-*-* x86_64-*-* } }
-// { dg-options "" }
+// Header file used by mv12.C and mv12-aux.cc.

 int foo () __attribute__ ((target ("default")));
 int foo () __attribute__ ((target ("sse4.2")));
Index: mv12-aux.C
===================================================================
--- mv12-aux.C (revision 196025)
+++ mv12-aux.C (working copy)
@@ -1,14 +0,0 @@
-// Test case to check if multiversioning works as expected when the versions
-// are defined in different files. Auxiliary file for mv12.C.
-
-// { dg-do compile { target i?86-*-* x86_64-*-* } }
-// { dg-require-ifunc "" }
-// { dg-options "-O2" }
-
-#include "mv12.h"
-
-__attribute__ ((target ("sse4.2")))
-int foo ()
-{
-  return 1;
-}

Thanks
Sri


>
>> --- g++.dg/ext/mv12-aux.C (revision 196025)
>> +++ g++.dg/ext/mv12-aux.C (working copy)
>> @@ -1,7 +1,10 @@
>>  // Test case to check if multiversioning works as expected when the versions
>>  // are defined in different files. Auxiliary file for mv12.C.
>> -// { dg-do compile }
>>
>> +// { dg-do compile { target i?86-*-* x86_64-*-* } }
>> +// { dg-require-ifunc "" }
>> +// { dg-options "-O2" }
>> +
>>  #include "mv12.h"
>>
>> This should fix the problem.
>
>         Jakub