score: Optimize object lookup

Use the maximum ID for the ID to object translation.  Using the maximum
ID gets rid of an additional load from the object information in
_Objects_Get().  In addition, object lookups fail for every ID in case
the object information is cleared to zero.  This makes it a bit more
robust during system startup (see new tests in spconfig02).

The local table no longer needs a NULL pointer entry at array index
zero.  Adjust all the object iteration loops accordingly.

Remove Objects_Information::minimum_id since it contains only redundant
information.  Add _Objects_Get_minimum_id() to get the minimum ID.

Update #3621.

11 files changed, 44 insertions, 65 deletions

diff --git a/cpukit/score/src/objectallocate.c b/cpukit/score/src/objectallocate.c
index 81e322757c..2f991477da 100644
--- a/cpukit/score/src/objectallocate.c
+++ b/cpukit/score/src/objectallocate.c
@@ -62,16 +62,15 @@ Objects_Control *_Objects_Allocate_unprotected(
      *  extend information base.
      */
 
-    if ( !the_object ) {
+    if ( the_object == NULL ) {
       _Objects_Extend_information( information );
       the_object = _Objects_Get_inactive( information );
     }
 
-    if ( the_object ) {
-      uint32_t   block;
+    if ( the_object != NULL ) {
+      Objects_Maximum block;
 
-      block = (uint32_t) _Objects_Get_index( the_object->id ) -
-              _Objects_Get_index( information->minimum_id );
+      block = _Objects_Get_index( the_object->id ) - OBJECTS_INDEX_MINIMUM;
       block /= information->objects_per_block;
 
       information->inactive_per_block[ block ]--;
diff --git a/cpukit/score/src/objectextendinformation.c b/cpukit/score/src/objectextendinformation.c
index b8e72f93b6..a8346ce937 100644
--- a/cpukit/score/src/objectextendinformation.c
+++ b/cpukit/score/src/objectextendinformation.c
@@ -48,7 +48,6 @@ void _Objects_Extend_information(
   uint32_t          block;
   uint32_t          index_base;
   uint32_t          index_end;
-  uint32_t          minimum_index;
   uint32_t          index;
   uint32_t          maximum;
   size_t            object_block_size;
@@ -65,11 +64,9 @@ void _Objects_Extend_information(
    *  extend the block table, then we will change do_extend.
    */
   do_extend     = true;
-  minimum_index = _Objects_Get_index( information->minimum_id );
-  index_base    = minimum_index;
+  index_base    = 0;
   block         = 0;
 
-  /* if ( information->maximum < minimum_index ) */
   if ( information->object_blocks == NULL )
     block_count = 0;
   else {
@@ -149,7 +146,7 @@ void _Objects_Extend_information(
      *  Allocate the tables and break it up.
      */
     object_blocks_size = block_count * sizeof( *object_blocks );
-    local_table_size = ( maximum + minimum_index ) * sizeof( *local_table );
+    local_table_size =  maximum * sizeof( *local_table );
     table_size = object_blocks_size
       + local_table_size
       + block_count * sizeof( *inactive_per_block );
@@ -181,7 +178,7 @@ void _Objects_Extend_information(
      */
     block_count--;
 
-    if ( information->maximum > minimum_index ) {
+    if ( information->maximum > 0 ) {
       /*
        *  Copy each section of the table over. This has to be performed as
        *  separate parts as size of each block has changed.
@@ -199,15 +196,8 @@ void _Objects_Extend_information(
       memcpy(
         local_table,
         information->local_table,
-        ( information->maximum + minimum_index ) * sizeof( *local_table )
+        information->maximum * sizeof( *local_table )
       );
-    } else {
-      /*
-       *  Deal with the special case of the 0 to minimum_index
-       */
-      for ( index = 0; index < minimum_index; index++ ) {
-        local_table[ index ] = NULL;
-      }
     }
 
     /*
@@ -256,7 +246,7 @@ void _Objects_Extend_information(
       information->the_api,
       information->the_class,
       _Objects_Local_node,
-      index
+      index + OBJECTS_INDEX_MINIMUM
     );
 
     _Chain_Initialize_node( &the_object->Node );
diff --git a/cpukit/score/src/objectfree.c b/cpukit/score/src/objectfree.c
index 3e7c8e409c..cf31a5b24e 100644
--- a/cpukit/score/src/objectfree.c
+++ b/cpukit/score/src/objectfree.c
@@ -37,8 +37,7 @@ void _Objects_Free(
     Objects_Maximum inactive;
 
     objects_per_block = information->objects_per_block;
-    block = _Objects_Get_index( the_object->id );
-    block -= _Objects_Get_index( information->minimum_id );
+    block = _Objects_Get_index( the_object->id ) - OBJECTS_INDEX_MINIMUM;
     block /= objects_per_block;
 
     ++information->inactive_per_block[ block ];
diff --git a/cpukit/score/src/objectgetlocal.c b/cpukit/score/src/objectgetlocal.c
index a1a81db436..e8a109f457 100644
--- a/cpukit/score/src/objectgetlocal.c
+++ b/cpukit/score/src/objectgetlocal.c
@@ -31,22 +31,29 @@ Objects_Control *_Objects_Get(
   const Objects_Information *information
 )
 {
-  uint32_t index;
+  Objects_Id delta;
+  Objects_Id maximum_id;
+  Objects_Id end;
 
-  index = id - information->minimum_id + 1;
+  maximum_id = information->maximum_id;
+  delta = maximum_id - id;
+  end = _Objects_Get_index( maximum_id );
 
-  if ( information->maximum >= index ) {
+  if ( RTEMS_PREDICT_TRUE( delta < end ) ) {
+    ISR_Level        level;
     Objects_Control *the_object;
 
-    _ISR_lock_ISR_disable( lock_context );
+    _ISR_Local_disable( level );
+    _ISR_lock_Context_set_level( lock_context, level );
 
-    the_object = information->local_table[ index ];
-    if ( the_object != NULL ) {
+    the_object =
+      information->local_table[ end - OBJECTS_INDEX_MINIMUM - delta ];
+    if ( RTEMS_PREDICT_TRUE( the_object != NULL ) ) {
       /* ISR disabled on behalf of caller */
       return the_object;
     }
 
-    _ISR_lock_ISR_enable( lock_context );
+    _ISR_Local_enable( level );
   }
 
   return NULL;
diff --git a/cpukit/score/src/objectgetnext.c b/cpukit/score/src/objectgetnext.c
index a46c02f2c2..054ed22fc1 100644
--- a/cpukit/score/src/objectgetnext.c
+++ b/cpukit/score/src/objectgetnext.c
@@ -36,7 +36,7 @@ Objects_Control *_Objects_Get_next(
       return NULL;
 
     if (_Objects_Get_index(id) == OBJECTS_ID_INITIAL_INDEX)
-        next_id = information->minimum_id;
+        next_id = _Objects_Get_minimum_id( information->maximum_id );
     else
         next_id = id;
 
diff --git a/cpukit/score/src/objectgetnoprotection.c b/cpukit/score/src/objectgetnoprotection.c
index 85692234fa..e5045b26de 100644
--- a/cpukit/score/src/objectgetnoprotection.c
+++ b/cpukit/score/src/objectgetnoprotection.c
@@ -25,19 +25,16 @@ Objects_Control *_Objects_Get_no_protection(
   const Objects_Information *information
 )
 {
-  Objects_Control *the_object;
-  uint32_t         index;
+  Objects_Id delta;
+  Objects_Id maximum_id;
+  Objects_Id end;
 
-  /*
-   * You can't just extract the index portion or you can get tricked
-   * by a value between 1 and maximum.
-   */
-  index = id - information->minimum_id + 1;
+  maximum_id = information->maximum_id;
+  delta = maximum_id - id;
+  end = _Objects_Get_index( maximum_id );
 
-  if ( information->maximum >= index ) {
-    if ( (the_object = information->local_table[ index ]) != NULL ) {
-      return the_object;
-    }
+  if ( RTEMS_PREDICT_TRUE( delta < end ) ) {
+    return information->local_table[ end - OBJECTS_INDEX_MINIMUM - delta ];
   }
 
   /*
diff --git a/cpukit/score/src/objectinitializeinformation.c b/cpukit/score/src/objectinitializeinformation.c
index a341dc1a5d..530e4e10ba 100644
--- a/cpukit/score/src/objectinitializeinformation.c
+++ b/cpukit/score/src/objectinitializeinformation.c
@@ -37,9 +37,7 @@ void _Objects_Do_initialize_information(
 #endif
 )
 {
-  static Objects_Control *null_local_table = NULL;
-  uint32_t                minimum_index;
-  Objects_Maximum         maximum_per_allocation;
+  Objects_Maximum maximum_per_allocation;
 
   information->the_api            = the_api;
   information->the_class          = the_class;
@@ -48,6 +46,7 @@ void _Objects_Do_initialize_information(
   information->inactive_per_block = 0;
   information->object_blocks      = 0;
   information->inactive           = 0;
+  information->local_table        = NULL;
 
   /*
    *  Set the maximum value to 0. It will be updated when objects are
@@ -79,18 +78,6 @@ void _Objects_Do_initialize_information(
   information->objects_per_block = maximum_per_allocation;
 
   /*
-   *  Provide a null local table entry for the case of any empty table.
-   */
-  information->local_table = &null_local_table;
-
-  /*
-   *  Calculate minimum and maximum Id's
-   */
-  minimum_index = (maximum_per_allocation == 0) ? 0 : 1;
-  information->minimum_id =
-    _Objects_Build_id( the_api, the_class, _Objects_Local_node, minimum_index );
-
-  /*
    *  Calculate the maximum name length
    *
    *  NOTE: Either 4 bytes for Classic API names or an arbitrary
diff --git a/cpukit/score/src/objectnametoid.c b/cpukit/score/src/objectnametoid.c
index 030d64a4bd..c3b014e3e1 100644
--- a/cpukit/score/src/objectnametoid.c
+++ b/cpukit/score/src/objectnametoid.c
@@ -29,7 +29,7 @@ Objects_Name_or_id_lookup_errors _Objects_Name_to_id_u32(
 {
   bool                       search_local_node;
   Objects_Control           *the_object;
-  uint32_t                   index;
+  Objects_Maximum            index;
 #if defined(RTEMS_MULTIPROCESSING)
   Objects_Name               name_for_mp;
 #endif
@@ -52,7 +52,7 @@ Objects_Name_or_id_lookup_errors _Objects_Name_to_id_u32(
    search_local_node = true;
 
   if ( search_local_node ) {
-    for ( index = 1; index <= information->maximum; index++ ) {
+    for ( index = 0; index < information->maximum; ++index ) {
       the_object = information->local_table[ index ];
       if ( !the_object )
         continue;
diff --git a/cpukit/score/src/objectnametoidstring.c b/cpukit/score/src/objectnametoidstring.c
index 3bca0441e0..a015d5fc25 100644
--- a/cpukit/score/src/objectnametoidstring.c
+++ b/cpukit/score/src/objectnametoidstring.c
@@ -52,7 +52,7 @@ Objects_Control *_Objects_Get_by_name(
     *name_length_p = name_length;
   }
 
-  for ( index = 1; index <= information->maximum; index++ ) {
+  for ( index = 0; index < information->maximum; ++index ) {
     Objects_Control *the_object;
 
     the_object = information->local_table[ index ];
diff --git a/cpukit/score/src/objectshrinkinformation.c b/cpukit/score/src/objectshrinkinformation.c
index cf3618f8fa..3b1841a16b 100644
--- a/cpukit/score/src/objectshrinkinformation.c
+++ b/cpukit/score/src/objectshrinkinformation.c
@@ -28,9 +28,9 @@ void _Objects_Shrink_information(
 )
 {
   Objects_Maximum objects_per_block;
-  Objects_Maximum index_base;
   Objects_Maximum block_count;
   Objects_Maximum block;
+  Objects_Maximum index_base;
 
   _Assert( _Objects_Allocator_is_owner() );
 
@@ -39,14 +39,14 @@ void _Objects_Shrink_information(
    */
 
   objects_per_block = information->objects_per_block;
-  index_base = _Objects_Get_index( information->minimum_id );
-  block_count = ( information->maximum - index_base ) / objects_per_block;
+  block_count = information->maximum / objects_per_block;
+  index_base = 0;
 
   for ( block = 0; block < block_count; block++ ) {
     if ( information->inactive_per_block[ block ] == objects_per_block ) {
       Chain_Node       *node;
       const Chain_Node *tail;
-      uint32_t          index_end;
+      Objects_Maximum   index_end;
 
       node = _Chain_First( &information->Inactive );
       tail = _Chain_Immutable_tail( &information->Inactive );
@@ -57,7 +57,7 @@ void _Objects_Shrink_information(
         uint32_t         index;
 
         object = (Objects_Control *) node;
-        index = _Objects_Get_index( object->id );
+        index = _Objects_Get_index( object->id ) - OBJECTS_INDEX_MINIMUM;
 
         /*
          *  Get the next node before the node is extracted
diff --git a/cpukit/score/src/threaditerate.c b/cpukit/score/src/threaditerate.c
index eff3472d57..9fa9b89166 100644
--- a/cpukit/score/src/threaditerate.c
+++ b/cpukit/score/src/threaditerate.c
@@ -39,7 +39,7 @@ void _Thread_Iterate(
       continue;
     }
 
-    for ( i = 1 ; i <= information->maximum ; ++i ) {
+    for ( i = 0 ; i < information->maximum ; ++i ) {
       Thread_Control *the_thread;
 
       the_thread = (Thread_Control *) information->local_table[ i ];