Refactor record_function_versions.

Renames record_function_versions to add_function_version, and make it
explicit that it is adding a single version to the function structure.

Additionally, change the insertion point to always maintain priority ordering
of the versions.

This allows for removing logic for moving the default to the first
position which was duplicated across target specific code and enables
easier reasoning about function sets.

gcc/ChangeLog:

	* cgraph.cc (cgraph_node::record_function_versions): Refactor and
	rename to...
	(cgraph_node::add_function_version): new function.
	* cgraph.h (cgraph_node::record_function_versions): Refactor and
	rename to...
	(cgraph_node::add_function_version): new function.
	* config/aarch64/aarch64.cc (aarch64_get_function_versions_dispatcher):
	Remove reordering.
	* config/i386/i386-features.cc (ix86_get_function_versions_dispatcher):
	Remove reordering.
	* config/riscv/riscv.cc (riscv_get_function_versions_dispatcher):
	Remove reordering.
	* config/rs6000/rs6000.cc (rs6000_get_function_versions_dispatcher):
	Remove reordering.

gcc/cp/ChangeLog:

	* decl.cc (maybe_version_functions): Change record_function_versions
	call to add_function_version.

diff --git a/gcc/cgraph.cc b/gcc/cgraph.cc
index 2f31260207df8f72e7e2817d2251ab47c1e4bd67..93353cbcb683bfe105333c3f1add96d77daab275 100644 (file)
--- a/gcc/cgraph.cc
+++ b/gcc/cgraph.cc
@@ -353,45 +353,60 @@ cgraph_node::delete_function_version_by_decl (tree decl)
   decl_node->remove ();
 }
 
-/* Record that DECL1 and DECL2 are semantically identical function
+/* Add decl to the structure of semantically identical function versions.
+   The node is inserted at the point maintaining the priority ordering on the
    versions.  */
 void
-cgraph_node::record_function_versions (tree decl1, tree decl2)
+cgraph_node::add_function_version (cgraph_function_version_info *fn_v,
+                                  tree decl)
 {
-  cgraph_node *decl1_node = cgraph_node::get_create (decl1);
-  cgraph_node *decl2_node = cgraph_node::get_create (decl2);
-  cgraph_function_version_info *decl1_v = NULL;
-  cgraph_function_version_info *decl2_v = NULL;
-  cgraph_function_version_info *before;
-  cgraph_function_version_info *after;
+  cgraph_node *decl_node = cgraph_node::get_create (decl);
+  cgraph_function_version_info *decl_v = NULL;
 
-  gcc_assert (decl1_node != NULL && decl2_node != NULL);
-  decl1_v = decl1_node->function_version ();
-  decl2_v = decl2_node->function_version ();
+  gcc_assert (decl_node != NULL);
 
-  if (decl1_v != NULL && decl2_v != NULL)
-    return;
-
-  if (decl1_v == NULL)
-    decl1_v = decl1_node->insert_new_function_version ();
-
-  if (decl2_v == NULL)
-    decl2_v = decl2_node->insert_new_function_version ();
-
-  /* Chain decl2_v and decl1_v.  All semantically identical versions
-     will be chained together.  */
+  decl_v = decl_node->function_version ();
 
-  before = decl1_v;
-  after = decl2_v;
+  /* If the nodes are already linked, skip.  */
+  if (decl_v != NULL && (decl_v->next || decl_v->prev))
+    return;
 
-  while (before->next != NULL)
-    before = before->next;
+  if (decl_v == NULL)
+    decl_v = decl_node->insert_new_function_version ();
+
+  gcc_assert (decl_v);
+  gcc_assert (fn_v);
+
+  /* Go to start of the FMV structure.  */
+  while (fn_v->prev)
+    fn_v = fn_v->prev;
+
+  cgraph_function_version_info *insert_point_before = NULL;
+  cgraph_function_version_info *insert_point_after = fn_v;
+
+  /* Find the insertion point for the new version to maintain ordering.
+     The default node must always go at the beginning.  */
+  if (!is_function_default_version (decl))
+    while (insert_point_after
+          && (targetm.compare_version_priority
+                (decl, insert_point_after->this_node->decl) > 0
+              || is_function_default_version
+                   (insert_point_after->this_node->decl)
+              || lookup_attribute
+                   ("target_clones",
+                    DECL_ATTRIBUTES (insert_point_after->this_node->decl))))
+      {
+       insert_point_before = insert_point_after;
+       insert_point_after = insert_point_after->next;
+      }
 
-  while (after->prev != NULL)
-    after= after->prev;
+  decl_v->prev = insert_point_before;
+  decl_v->next= insert_point_after;
 
-  before->next = after;
-  after->prev = before;
+  if (insert_point_before)
+    insert_point_before->next = decl_v;
+  if (insert_point_after)
+    insert_point_after->prev = decl_v;
 }
 
 /* Initialize callgraph dump file.  */

diff --git a/gcc/cgraph.h b/gcc/cgraph.h
index 970ac2cba376f30c93977c376449e803fae63abf..deca564a8e37b9feef018d21a63c3a73647bda51 100644 (file)
--- a/gcc/cgraph.h
+++ b/gcc/cgraph.h
@@ -1339,9 +1339,9 @@ struct GTY((tag ("SYMTAB_FUNCTION"))) cgraph_node : public symtab_node
     return m_summary_id;
   }
 
-  /* Record that DECL1 and DECL2 are semantically identical function
-     versions.  */
-  static void record_function_versions (tree decl1, tree decl2);
+  /* Adds DECL to the FN_V structure of semantically identical functions.  */
+  static void add_function_version (cgraph_function_version_info *fn_v,
+                                   tree decl);
 
   /* Remove the cgraph_function_version_info and cgraph_node for DECL.  This
      DECL is a duplicate declaration.  */

diff --git a/gcc/config/aarch64/aarch64.cc b/gcc/config/aarch64/aarch64.cc
index 59ac08483f4de4da1e2522af0f1c7cc5279ecf41..c8977b5a9481c33c89b18d643c0d8d4c47594484 100644 (file)
--- a/gcc/config/aarch64/aarch64.cc
+++ b/gcc/config/aarch64/aarch64.cc
@@ -20862,7 +20862,6 @@ aarch64_get_function_versions_dispatcher (void *decl)
   struct cgraph_node *node = NULL;
   struct cgraph_node *default_node = NULL;
   struct cgraph_function_version_info *node_v = NULL;
-  struct cgraph_function_version_info *first_v = NULL;
 
   tree dispatch_decl = NULL;
 
@@ -20879,37 +20878,16 @@ aarch64_get_function_versions_dispatcher (void *decl)
   if (node_v->dispatcher_resolver != NULL)
     return node_v->dispatcher_resolver;
 
-  /* Find the default version and make it the first node.  */
-  first_v = node_v;
-  /* Go to the beginning of the chain.  */
-  while (first_v->prev != NULL)
-    first_v = first_v->prev;
-  default_version_info = first_v;
-  while (default_version_info != NULL)
-    {
-      if (get_feature_mask_for_version
-           (default_version_info->this_node->decl) == 0ULL)
-       break;
-      default_version_info = default_version_info->next;
-    }
+  /* The default node is always the beginning of the chain.  */
+  default_version_info = node_v;
+  while (default_version_info->prev)
+    default_version_info = default_version_info->prev;
+  default_node = default_version_info->this_node;
 
   /* If there is no default node, just return NULL.  */
-  if (default_version_info == NULL)
+  if (!is_function_default_version (default_node->decl))
     return NULL;
 
-  /* Make default info the first node.  */
-  if (first_v != default_version_info)
-    {
-      default_version_info->prev->next = default_version_info->next;
-      if (default_version_info->next)
-       default_version_info->next->prev = default_version_info->prev;
-      first_v->prev = default_version_info;
-      default_version_info->next = first_v;
-      default_version_info->prev = NULL;
-    }
-
-  default_node = default_version_info->this_node;
-
   if (targetm.has_ifunc_p ())
     {
       struct cgraph_function_version_info *it_v = NULL;

diff --git a/gcc/config/i386/i386-features.cc b/gcc/config/i386/i386-features.cc
index b1682c2fad444923f698da4d07573a09c8e9047d..56ab7f2d23b0450e7901224d41c0538eb583e8b5 100644 (file)
--- a/gcc/config/i386/i386-features.cc
+++ b/gcc/config/i386/i386-features.cc
@@ -4284,7 +4284,6 @@ ix86_get_function_versions_dispatcher (void *decl)
   struct cgraph_node *node = NULL;
   struct cgraph_node *default_node = NULL;
   struct cgraph_function_version_info *node_v = NULL;
-  struct cgraph_function_version_info *first_v = NULL;
 
   tree dispatch_decl = NULL;
 
@@ -4301,37 +4300,16 @@ ix86_get_function_versions_dispatcher (void *decl)
   if (node_v->dispatcher_resolver != NULL)
     return node_v->dispatcher_resolver;
 
-  /* Find the default version and make it the first node.  */
-  first_v = node_v;
-  /* Go to the beginning of the chain.  */
-  while (first_v->prev != NULL)
-    first_v = first_v->prev;
-  default_version_info = first_v;
-  while (default_version_info != NULL)
-    {
-      if (is_function_default_version
-           (default_version_info->this_node->decl))
-       break;
-      default_version_info = default_version_info->next;
-    }
+  /* The default node is always the beginning of the chain.  */
+  default_version_info = node_v;
+  while (default_version_info->prev != NULL)
+    default_version_info = default_version_info->prev;
+  default_node = default_version_info->this_node;
 
   /* If there is no default node, just return NULL.  */
-  if (default_version_info == NULL)
+  if (!is_function_default_version (default_node->decl))
     return NULL;
 
-  /* Make default info the first node.  */
-  if (first_v != default_version_info)
-    {
-      default_version_info->prev->next = default_version_info->next;
-      if (default_version_info->next)
-       default_version_info->next->prev = default_version_info->prev;
-      first_v->prev = default_version_info;
-      default_version_info->next = first_v;
-      default_version_info->prev = NULL;
-    }
-
-  default_node = default_version_info->this_node;
-
 #if defined (ASM_OUTPUT_TYPE_DIRECTIVE)
   if (targetm.has_ifunc_p ())
     {

diff --git a/gcc/config/riscv/riscv.cc b/gcc/config/riscv/riscv.cc
index c6e0ffb0755e546619fc8c34806d1b917112e4aa..2dd459ad09f7306dab673c93eea4196c23d698eb 100644 (file)
--- a/gcc/config/riscv/riscv.cc
+++ b/gcc/config/riscv/riscv.cc
@@ -13953,7 +13953,6 @@ riscv_get_function_versions_dispatcher (void *decl)
   struct cgraph_node *node = NULL;
   struct cgraph_node *default_node = NULL;
   struct cgraph_function_version_info *node_v = NULL;
-  struct cgraph_function_version_info *first_v = NULL;
 
   tree dispatch_decl = NULL;
 
@@ -13970,41 +13969,16 @@ riscv_get_function_versions_dispatcher (void *decl)
   if (node_v->dispatcher_resolver != NULL)
     return node_v->dispatcher_resolver;
 
-  /* Find the default version and make it the first node.  */
-  first_v = node_v;
-  /* Go to the beginning of the chain.  */
-  while (first_v->prev != NULL)
-    first_v = first_v->prev;
-  default_version_info = first_v;
-
-  while (default_version_info != NULL)
-    {
-      struct riscv_feature_bits res;
-      int priority; /* Unused.  */
-      parse_features_for_version (default_version_info->this_node->decl,
-                                 res, priority);
-      if (res.length == 0)
-       break;
-      default_version_info = default_version_info->next;
-    }
+  /* The default node is always the beginning of the chain.  */
+  default_version_info = node_v;
+  while (default_version_info->prev)
+    default_version_info = default_version_info->prev;
+  default_node = default_version_info->this_node;
 
   /* If there is no default node, just return NULL.  */
-  if (default_version_info == NULL)
+  if (!is_function_default_version (default_node->decl))
     return NULL;
 
-  /* Make default info the first node.  */
-  if (first_v != default_version_info)
-    {
-      default_version_info->prev->next = default_version_info->next;
-      if (default_version_info->next)
-       default_version_info->next->prev = default_version_info->prev;
-      first_v->prev = default_version_info;
-      default_version_info->next = first_v;
-      default_version_info->prev = NULL;
-    }
-
-  default_node = default_version_info->this_node;
-
   if (targetm.has_ifunc_p ())
     {
       struct cgraph_function_version_info *it_v = NULL;

diff --git a/gcc/config/rs6000/rs6000.cc b/gcc/config/rs6000/rs6000.cc
index 7375c36e406d59441fe135ff0828d6247ff8ba4c..7ee26e52b1380210a28b9c0e451144ceb6b2d86a 100644 (file)
--- a/gcc/config/rs6000/rs6000.cc
+++ b/gcc/config/rs6000/rs6000.cc
@@ -25312,7 +25312,6 @@ rs6000_get_function_versions_dispatcher (void *decl)
   struct cgraph_node *node = NULL;
   struct cgraph_node *default_node = NULL;
   struct cgraph_function_version_info *node_v = NULL;
-  struct cgraph_function_version_info *first_v = NULL;
 
   tree dispatch_decl = NULL;
 
@@ -25332,38 +25331,16 @@ rs6000_get_function_versions_dispatcher (void *decl)
   if (node_v->dispatcher_resolver != NULL)
     return node_v->dispatcher_resolver;
 
-  /* Find the default version and make it the first node.  */
-  first_v = node_v;
-  /* Go to the beginning of the chain.  */
-  while (first_v->prev != NULL)
-    first_v = first_v->prev;
-
-  default_version_info = first_v;
-  while (default_version_info != NULL)
-    {
-      const tree decl2 = default_version_info->this_node->decl;
-      if (is_function_default_version (decl2))
-        break;
-      default_version_info = default_version_info->next;
-    }
+  /* The default node is always the beginning of the chain.  */
+  default_version_info = node_v;
+  while (default_version_info->prev)
+    default_version_info = default_version_info->prev;
+  default_node = default_version_info->this_node;
 
   /* If there is no default node, just return NULL.  */
-  if (default_version_info == NULL)
+  if (!is_function_default_version (default_node->decl))
     return NULL;
 
-  /* Make default info the first node.  */
-  if (first_v != default_version_info)
-    {
-      default_version_info->prev->next = default_version_info->next;
-      if (default_version_info->next)
-        default_version_info->next->prev = default_version_info->prev;
-      first_v->prev = default_version_info;
-      default_version_info->next = first_v;
-      default_version_info->prev = NULL;
-    }
-
-  default_node = default_version_info->this_node;
-
 #ifndef TARGET_LIBC_PROVIDES_HWCAP_IN_TCB
   error_at (DECL_SOURCE_LOCATION (default_node->decl),
            "%<target_clones%> attribute needs GLIBC (2.23 and newer) that "

diff --git a/gcc/cp/decl.cc b/gcc/cp/decl.cc
index 9a20ed62738f3bc2e87eaed7cf38d0c66aed729d..4c8a2052aee245446958de78e1e39c559292045a 100644 (file)
--- a/gcc/cp/decl.cc
+++ b/gcc/cp/decl.cc
@@ -1311,7 +1311,15 @@ maybe_version_functions (tree newdecl, tree olddecl, bool record)
     }
 
   if (record)
-    cgraph_node::record_function_versions (olddecl, newdecl);
+    {
+      /* Add the new version to the function version structure.  */
+      cgraph_node *fn_node = cgraph_node::get_create (olddecl);
+      cgraph_function_version_info *fn_v = fn_node->function_version ();
+      if (!fn_v)
+       fn_v = fn_node->insert_new_function_version ();
+
+      cgraph_node::add_function_version (fn_v, newdecl);
+    }
 
   return true;
 }