Remap multiple items in referenced data.

This patch increases the performance when remapping data.
{D13615} introduced a mechanism to remap multiple items in a single go.
This patch uses the same mechanism when remapping data inside ID datablocks.

Benchmark results when loading the village scene of sprite fright on AMD Ryzen 7 3800X 8-Core Processor
Before this patch 115 seconds
When patch applied less than 43 seconds

There is still some room for improvement by porting relink code.

Reviewed By: mont29

Maniphest Tasks: T95279

Differential Revision: https://developer.blender.org/D14043

7 files changed, 344 insertions, 145 deletions

diff --git a/source/blender/blenkernel/BKE_lib_id.h b/source/blender/blenkernel/BKE_lib_id.h
index c4aa44706d5..c56cb616a9a 100644
--- a/source/blender/blenkernel/BKE_lib_id.h
+++ b/source/blender/blenkernel/BKE_lib_id.h
@@ -69,6 +69,11 @@ void *BKE_libblock_alloc(struct Main *bmain, short type, const char *name, int f
  */
 void BKE_libblock_init_empty(struct ID *id) ATTR_NONNULL(1);
 
+/**
+ * Reset the runtime counters used by ID remapping.
+ */
+void BKE_libblock_runtime_reset_remapping_status(struct ID *id) ATTR_NONNULL(1);
+
 /* *** ID's session_uuid management. *** */
 
 /**
diff --git a/source/blender/blenkernel/BKE_lib_remap.h b/source/blender/blenkernel/BKE_lib_remap.h
index f4136ed5cda..94b94303ec9 100644
--- a/source/blender/blenkernel/BKE_lib_remap.h
+++ b/source/blender/blenkernel/BKE_lib_remap.h
@@ -77,17 +77,25 @@ enum {
   ID_REMAP_FORCE_OBDATA_IN_EDITMODE = 1 << 9,
 };
 
+typedef enum eIDRemapType {
+  /** Remap an ID reference to a new reference. The new reference can also be null. */
+  ID_REMAP_TYPE_REMAP = 0,
+
+  /** Cleanup all IDs used by a specific one. */
+  ID_REMAP_TYPE_CLEANUP = 1,
+} eIDRemapType;
+
 /**
  * Replace all references in given Main using the given \a mappings
  *
  * \note Is preferred over BKE_libblock_remap_locked due to performance.
  */
 void BKE_libblock_remap_multiple_locked(struct Main *bmain,
-                                        const struct IDRemapper *mappings,
+                                        struct IDRemapper *mappings,
                                         const short remap_flags);
 
 void BKE_libblock_remap_multiple(struct Main *bmain,
-                                 const struct IDRemapper *mappings,
+                                 struct IDRemapper *mappings,
                                  const short remap_flags);
 
 /**
@@ -172,6 +180,13 @@ typedef enum IDRemapperApplyOptions {
    */
   ID_REMAP_APPLY_ENSURE_REAL = (1 << 1),
 
+  /**
+   * Unassign in stead of remap when the new ID datablock would become id_self.
+   *
+   * To use this option 'BKE_id_remapper_apply_ex' must be used with a not-null id_self parameter.
+   */
+  ID_REMAP_APPLY_UNMAP_WHEN_REMAPPING_TO_SELF = (1 << 2),
+
   ID_REMAP_APPLY_DEFAULT = 0,
 } IDRemapperApplyOptions;
 
@@ -199,7 +214,28 @@ void BKE_id_remapper_add(struct IDRemapper *id_remapper, struct ID *old_id, stru
 IDRemapperApplyResult BKE_id_remapper_apply(const struct IDRemapper *id_remapper,
                                             struct ID **r_id_ptr,
                                             IDRemapperApplyOptions options);
+/**
+ * Apply a remapping.
+ *
+ * Use this function when `ID_REMAP_APPLY_UNMAP_WHEN_REMAPPING_TO_SELF`. In this case
+ * the #id_self parameter is required. Otherwise the #BKE_id_remapper_apply can be used.
+ *
+ * \param id_self required for ID_REMAP_APPLY_UNMAP_WHEN_REMAPPING_TO_SELF.
+ *     When remapping to id_self it will then be remapped to NULL.
+ */
+IDRemapperApplyResult BKE_id_remapper_apply_ex(const struct IDRemapper *id_remapper,
+                                               struct ID **r_id_ptr,
+                                               IDRemapperApplyOptions options,
+                                               struct ID *id_self);
 bool BKE_id_remapper_has_mapping_for(const struct IDRemapper *id_remapper, uint64_t type_filter);
+
+/**
+ * Determine the mapping result, without applying the mapping.
+ */
+IDRemapperApplyResult BKE_id_remapper_get_mapping_result(const struct IDRemapper *id_remapper,
+                                                         struct ID *id,
+                                                         IDRemapperApplyOptions options,
+                                                         const struct ID *id_self);
 void BKE_id_remapper_iter(const struct IDRemapper *id_remapper,
                           IDRemapperIterFunction func,
                           void *user_data);
diff --git a/source/blender/blenkernel/intern/lib_id.c b/source/blender/blenkernel/intern/lib_id.c
index 2baecea51ff..7cd3204f3f1 100644
--- a/source/blender/blenkernel/intern/lib_id.c
+++ b/source/blender/blenkernel/intern/lib_id.c
@@ -1121,6 +1121,14 @@ void BKE_libblock_init_empty(ID *id)
   BLI_assert_msg(0, "IDType Missing IDTypeInfo");
 }
 
+void BKE_libblock_runtime_reset_remapping_status(ID *id)
+{
+  id->runtime.remap.status = 0;
+  id->runtime.remap.skipped_refcounted = 0;
+  id->runtime.remap.skipped_direct = 0;
+  id->runtime.remap.skipped_indirect = 0;
+}
+
 /* ********** ID session-wise UUID management. ********** */
 static uint global_session_uuid = 0;
 
diff --git a/source/blender/blenkernel/intern/lib_id_remapper.cc b/source/blender/blenkernel/intern/lib_id_remapper.cc
index 5af482ac088..7696386c87d 100644
--- a/source/blender/blenkernel/intern/lib_id_remapper.cc
+++ b/source/blender/blenkernel/intern/lib_id_remapper.cc
@@ -44,7 +44,25 @@ struct IDRemapper {
     return (source_types & filter) != 0;
   }
 
-  IDRemapperApplyResult apply(ID **r_id_ptr, IDRemapperApplyOptions options) const
+  IDRemapperApplyResult get_mapping_result(ID *id,
+                                           IDRemapperApplyOptions options,
+                                           const ID *id_self) const
+  {
+    if (!mappings.contains(id)) {
+      return ID_REMAP_RESULT_SOURCE_UNAVAILABLE;
+    }
+    const ID *new_id = mappings.lookup(id);
+    if ((options & ID_REMAP_APPLY_UNMAP_WHEN_REMAPPING_TO_SELF) != 0 && id_self == new_id) {
+      new_id = nullptr;
+    }
+    if (new_id == nullptr) {
+      return ID_REMAP_RESULT_SOURCE_UNASSIGNED;
+    }
+
+    return ID_REMAP_RESULT_SOURCE_REMAPPED;
+  }
+
+  IDRemapperApplyResult apply(ID **r_id_ptr, IDRemapperApplyOptions options, ID *id_self) const
   {
     BLI_assert(r_id_ptr != nullptr);
     if (*r_id_ptr == nullptr) {
@@ -60,6 +78,9 @@ struct IDRemapper {
     }
 
     *r_id_ptr = mappings.lookup(*r_id_ptr);
+    if (options & ID_REMAP_APPLY_UNMAP_WHEN_REMAPPING_TO_SELF && *r_id_ptr == id_self) {
+      *r_id_ptr = nullptr;
+    }
     if (*r_id_ptr == nullptr) {
       return ID_REMAP_RESULT_SOURCE_UNASSIGNED;
     }
@@ -142,12 +163,35 @@ bool BKE_id_remapper_has_mapping_for(const struct IDRemapper *id_remapper, uint6
   return remapper->contains_mappings_for_any(type_filter);
 }
 
+IDRemapperApplyResult BKE_id_remapper_get_mapping_result(const struct IDRemapper *id_remapper,
+                                                         struct ID *id,
+                                                         IDRemapperApplyOptions options,
+                                                         const struct ID *id_self)
+{
+  const blender::bke::id::remapper::IDRemapper *remapper = unwrap(id_remapper);
+  return remapper->get_mapping_result(id, options, id_self);
+}
+
+IDRemapperApplyResult BKE_id_remapper_apply_ex(const IDRemapper *id_remapper,
+                                               ID **r_id_ptr,
+                                               const IDRemapperApplyOptions options,
+                                               ID *id_self)
+{
+  BLI_assert_msg((options & ID_REMAP_APPLY_UNMAP_WHEN_REMAPPING_TO_SELF) == 0 ||
+                     id_self != nullptr,
+                 "ID_REMAP_APPLY_WHEN_REMAPPING_TO_SELF requires id_self parameter.");
+  const blender::bke::id::remapper::IDRemapper *remapper = unwrap(id_remapper);
+  return remapper->apply(r_id_ptr, options, id_self);
+}
+
 IDRemapperApplyResult BKE_id_remapper_apply(const IDRemapper *id_remapper,
                                             ID **r_id_ptr,
                                             const IDRemapperApplyOptions options)
 {
-  const blender::bke::id::remapper::IDRemapper *remapper = unwrap(id_remapper);
-  return remapper->apply(r_id_ptr, options);
+  BLI_assert_msg((options & ID_REMAP_APPLY_UNMAP_WHEN_REMAPPING_TO_SELF) == 0,
+                 "ID_REMAP_APPLY_UNMAP_WHEN_REMAPPING_TO_SELF requires id_self parameter. Use "
+                 "`BKE_id_remapper_apply_ex`.");
+  return BKE_id_remapper_apply_ex(id_remapper, r_id_ptr, options, nullptr);
 }
 
 void BKE_id_remapper_iter(const struct IDRemapper *id_remapper,
diff --git a/source/blender/blenkernel/intern/lib_id_remapper_test.cc b/source/blender/blenkernel/intern/lib_id_remapper_test.cc
index a6cfe60153d..73edc30d077 100644
--- a/source/blender/blenkernel/intern/lib_id_remapper_test.cc
+++ b/source/blender/blenkernel/intern/lib_id_remapper_test.cc
@@ -65,4 +65,44 @@ TEST(lib_id_remapper, unassigned)
   BKE_id_remapper_free(remapper);
 }
 
+TEST(lib_id_remapper, unassign_when_mapped_to_self)
+{
+  ID id_self;
+  ID id1;
+  ID id2;
+  ID *idp;
+
+  BLI_strncpy(id_self.name, "OBSelf", sizeof(id1.name));
+  BLI_strncpy(id1.name, "OB1", sizeof(id1.name));
+  BLI_strncpy(id2.name, "OB2", sizeof(id2.name));
+
+  /* Default mapping behavior. Should just remap to id2. */
+  idp = &id1;
+  IDRemapper *remapper = BKE_id_remapper_create();
+  BKE_id_remapper_add(remapper, &id1, &id2);
+  IDRemapperApplyResult result = BKE_id_remapper_apply_ex(
+      remapper, &idp, ID_REMAP_APPLY_UNMAP_WHEN_REMAPPING_TO_SELF, &id_self);
+  EXPECT_EQ(result, ID_REMAP_RESULT_SOURCE_REMAPPED);
+  EXPECT_EQ(idp, &id2);
+
+  /* Default mapping behavior. Should unassign. */
+  idp = &id1;
+  BKE_id_remapper_clear(remapper);
+  BKE_id_remapper_add(remapper, &id1, nullptr);
+  result = BKE_id_remapper_apply_ex(
+      remapper, &idp, ID_REMAP_APPLY_UNMAP_WHEN_REMAPPING_TO_SELF, &id_self);
+  EXPECT_EQ(result, ID_REMAP_RESULT_SOURCE_UNASSIGNED);
+  EXPECT_EQ(idp, nullptr);
+
+  /* Unmap when remapping to self behavior. Should unassign. */
+  idp = &id1;
+  BKE_id_remapper_clear(remapper);
+  BKE_id_remapper_add(remapper, &id1, &id_self);
+  result = BKE_id_remapper_apply_ex(
+      remapper, &idp, ID_REMAP_APPLY_UNMAP_WHEN_REMAPPING_TO_SELF, &id_self);
+  EXPECT_EQ(result, ID_REMAP_RESULT_SOURCE_UNASSIGNED);
+  EXPECT_EQ(idp, nullptr);
+  BKE_id_remapper_free(remapper);
+}
+
 }  // namespace blender::bke::id::remapper::tests
diff --git a/source/blender/blenkernel/intern/lib_remap.c b/source/blender/blenkernel/intern/lib_remap.c
index a05067e16f6..9329a09f1b6 100644
--- a/source/blender/blenkernel/intern/lib_remap.c
+++ b/source/blender/blenkernel/intern/lib_remap.c
@@ -51,35 +51,20 @@ void BKE_library_callback_remap_editor_id_reference_set(
 }
 
 typedef struct IDRemap {
+  eIDRemapType type;
   Main *bmain; /* Only used to trigger depsgraph updates in the right bmain. */
-  ID *old_id;
-  ID *new_id;
+
+  struct IDRemapper *id_remapper;
+
   /** The ID in which we are replacing old_id by new_id usages. */
   ID *id_owner;
   short flag;
-
-  /* 'Output' data. */
-  short status;
-  /** Number of direct use cases that could not be remapped (e.g.: obdata when in edit mode). */
-  int skipped_direct;
-  /** Number of indirect use cases that could not be remapped. */
-  int skipped_indirect;
-  /** Number of skipped use cases that refcount the data-block. */
-  int skipped_refcounted;
 } IDRemap;
 
 /* IDRemap->flag enums defined in BKE_lib.h */
 
-/* IDRemap->status */
-enum {
-  /* *** Set by callback. *** */
-  ID_REMAP_IS_LINKED_DIRECT = 1 << 0,    /* new_id is directly linked in current .blend. */
-  ID_REMAP_IS_USER_ONE_SKIPPED = 1 << 1, /* There was some skipped 'user_one' usages of old_id. */
-};
-
 static void foreach_libblock_remap_callback_skip(const ID *UNUSED(id_owner),
-                                                 ID **UNUSED(id_ptr),
-                                                 IDRemap *id_remap_data,
+                                                 ID **id_ptr,
                                                  const int cb_flag,
                                                  const bool is_indirect,
                                                  const bool is_reference,
@@ -87,37 +72,40 @@ static void foreach_libblock_remap_callback_skip(const ID *UNUSED(id_owner),
                                                  const bool UNUSED(is_obj),
                                                  const bool is_obj_editmode)
 {
+  ID *id = *id_ptr;
+  BLI_assert(id != NULL);
   if (is_indirect) {
-    id_remap_data->skipped_indirect++;
+    id->runtime.remap.skipped_indirect++;
   }
   else if (violates_never_null || is_obj_editmode || is_reference) {
-    id_remap_data->skipped_direct++;
+    id->runtime.remap.skipped_direct++;
   }
   else {
     BLI_assert(0);
   }
   if (cb_flag & IDWALK_CB_USER) {
-    id_remap_data->skipped_refcounted++;
+    id->runtime.remap.skipped_refcounted++;
   }
   else if (cb_flag & IDWALK_CB_USER_ONE) {
     /* No need to count number of times this happens, just a flag is enough. */
-    id_remap_data->status |= ID_REMAP_IS_USER_ONE_SKIPPED;
+    id->runtime.remap.status |= ID_REMAP_IS_USER_ONE_SKIPPED;
   }
 }
 
 static void foreach_libblock_remap_callback_apply(ID *id_owner,
                                                   ID *id_self,
-                                                  ID *old_id,
-                                                  ID *new_id,
                                                   ID **id_ptr,
                                                   IDRemap *id_remap_data,
+                                                  const struct IDRemapper *mappings,
+                                                  const IDRemapperApplyOptions id_remapper_options,
                                                   const int cb_flag,
                                                   const bool is_indirect,
                                                   const bool violates_never_null,
                                                   const bool force_user_refcount)
 {
+  ID *old_id = *id_ptr;
   if (!violates_never_null) {
-    *id_ptr = new_id;
+    BKE_id_remapper_apply_ex(mappings, id_ptr, id_remapper_options, id_self);
     DEG_id_tag_update_ex(id_remap_data->bmain,
                          id_self,
                          ID_RECALC_COPY_ON_WRITE | ID_RECALC_TRANSFORM | ID_RECALC_GEOMETRY);
@@ -127,6 +115,10 @@ static void foreach_libblock_remap_callback_apply(ID *id_owner,
                            ID_RECALC_COPY_ON_WRITE | ID_RECALC_TRANSFORM | ID_RECALC_GEOMETRY);
     }
   }
+  /* Get the new_id pointer. When the mapping is violating never null we should use a NULL
+   * pointer otherwise the incorrect users are decreased and increased on the same instance. */
+  ID *new_id = violates_never_null ? NULL : *id_ptr;
+
   if (cb_flag & IDWALK_CB_USER) {
     /* NOTE: by default we don't user-count IDs which are not in the main database.
      * This is because in certain conditions we can have data-blocks in
@@ -147,8 +139,8 @@ static void foreach_libblock_remap_callback_apply(ID *id_owner,
     /* We cannot affect old_id->us directly, LIB_TAG_EXTRAUSER(_SET)
      * are assumed to be set as needed, that extra user is processed in final handling. */
   }
-  if (!is_indirect) {
-    id_remap_data->status |= ID_REMAP_IS_LINKED_DIRECT;
+  if (!is_indirect && new_id) {
+    new_id->runtime.remap.status |= ID_REMAP_IS_LINKED_DIRECT;
   }
 }
 
@@ -164,28 +156,43 @@ static int foreach_libblock_remap_callback(LibraryIDLinkCallbackData *cb_data)
   ID *id_self = cb_data->id_self;
   ID **id_p = cb_data->id_pointer;
   IDRemap *id_remap_data = cb_data->user_data;
-  ID *old_id = id_remap_data->old_id;
-  ID *new_id = id_remap_data->new_id;
 
   /* Those asserts ensure the general sanity of ID tags regarding 'embedded' ID data (root
    * nodetrees and co). */
   BLI_assert(id_owner == id_remap_data->id_owner);
   BLI_assert(id_self == id_owner || (id_self->flag & LIB_EMBEDDED_DATA) != 0);
 
-  if (!old_id) { /* Used to cleanup all IDs used by a specific one. */
-    BLI_assert(!new_id);
-    old_id = *id_p;
+  /* Early exit when id pointer isn't set. */
+  if (*id_p == NULL) {
+    return IDWALK_RET_NOP;
   }
 
-  /* Early exit when id pointer isn't set to an expected value. */
-  if (*id_p == NULL || *id_p != old_id) {
-    return IDWALK_RET_NOP;
+  struct IDRemapper *id_remapper = id_remap_data->id_remapper;
+  IDRemapperApplyOptions id_remapper_options = ID_REMAP_APPLY_DEFAULT;
+
+  /* Used to cleanup all IDs used by a specific one. */
+  if (id_remap_data->type == ID_REMAP_TYPE_CLEANUP) {
+    /* Clearing existing instance to reduce potential lookup times for IDs referencing many other
+     * IDs. This makes sure that there will only be a single rule in the id_remapper. */
+    BKE_id_remapper_clear(id_remapper);
+    BKE_id_remapper_add(id_remapper, *id_p, NULL);
   }
 
   /* Better remap to NULL than not remapping at all,
    * then we can handle it as a regular remap-to-NULL case. */
-  if ((cb_flag & IDWALK_CB_NEVER_SELF) && (new_id == id_self)) {
-    new_id = NULL;
+  if ((cb_flag & IDWALK_CB_NEVER_SELF)) {
+    id_remapper_options |= ID_REMAP_APPLY_UNMAP_WHEN_REMAPPING_TO_SELF;
+  }
+
+  const IDRemapperApplyResult expected_mapping_result = BKE_id_remapper_get_mapping_result(
+      id_remapper, *id_p, id_remapper_options, id_self);
+  /* Exit, when no modifications will be done; ensuring id->runtime counters won't changed. */
+  if (ELEM(expected_mapping_result,
+           ID_REMAP_RESULT_SOURCE_UNAVAILABLE,
+           ID_REMAP_RESULT_SOURCE_NOT_MAPPABLE)) {
+    BLI_assert_msg(id_remap_data->type == ID_REMAP_TYPE_REMAP,
+                   "Cleanup should always do unassign.");
+    return IDWALK_RET_NOP;
   }
 
   const bool is_reference = (cb_flag & IDWALK_CB_OVERRIDE_LIBRARY_REFERENCE) != 0;
@@ -196,7 +203,9 @@ static int foreach_libblock_remap_callback(LibraryIDLinkCallbackData *cb_data)
    * remapped in this situation. */
   const bool is_obj_editmode = (is_obj && BKE_object_is_in_editmode((Object *)id_owner) &&
                                 (id_remap_data->flag & ID_REMAP_FORCE_OBDATA_IN_EDITMODE) == 0);
-  const bool violates_never_null = ((cb_flag & IDWALK_CB_NEVER_NULL) && (new_id == NULL) &&
+  const bool violates_never_null = ((cb_flag & IDWALK_CB_NEVER_NULL) &&
+                                    (expected_mapping_result ==
+                                     ID_REMAP_RESULT_SOURCE_UNASSIGNED) &&
                                     (id_remap_data->flag & ID_REMAP_FORCE_NEVER_NULL_USAGE) == 0);
   const bool skip_reference = (id_remap_data->flag & ID_REMAP_SKIP_OVERRIDE_LIBRARY) != 0;
   const bool skip_never_null = (id_remap_data->flag & ID_REMAP_SKIP_NEVER_NULL_USAGE) != 0;
@@ -204,14 +213,13 @@ static int foreach_libblock_remap_callback(LibraryIDLinkCallbackData *cb_data)
 
 #ifdef DEBUG_PRINT
   printf(
-      "In %s (lib %p): Remapping %s (%p) to %s (%p) "
+      "In %s (lib %p): Remapping %s (%p) remap operation: %s "
       "(is_indirect: %d, skip_indirect: %d, is_reference: %d, skip_reference: %d)\n",
-      id->name,
-      id->lib,
-      old_id->name,
-      old_id,
-      new_id ? new_id->name : "<NONE>",
-      new_id,
+      id_owner->name,
+      id_owner->lib,
+      (*id_p)->name,
+      *id_p,
+      BKE_id_remapper_result_string(expected_mapping_result),
       is_indirect,
       skip_indirect,
       is_reference,
@@ -226,11 +234,11 @@ static int foreach_libblock_remap_callback(LibraryIDLinkCallbackData *cb_data)
    * (otherwise, we follow common NEVER_NULL flags).
    * (skipped_indirect too). */
   if ((violates_never_null && skip_never_null) ||
-      (is_obj_editmode && (((Object *)id_owner)->data == *id_p) && new_id != NULL) ||
+      (is_obj_editmode && (((Object *)id_owner)->data == *id_p) &&
+       (expected_mapping_result == ID_REMAP_RESULT_SOURCE_REMAPPED)) ||
       (skip_indirect && is_indirect) || (is_reference && skip_reference)) {
     foreach_libblock_remap_callback_skip(id_owner,
                                          id_p,
-                                         id_remap_data,
                                          cb_flag,
                                          is_indirect,
                                          is_reference,
@@ -241,10 +249,10 @@ static int foreach_libblock_remap_callback(LibraryIDLinkCallbackData *cb_data)
   else {
     foreach_libblock_remap_callback_apply(id_owner,
                                           id_self,
-                                          old_id,
-                                          new_id,
                                           id_p,
                                           id_remap_data,
+                                          id_remapper,
+                                          id_remapper_options,
                                           cb_flag,
                                           is_indirect,
                                           violates_never_null,
@@ -254,27 +262,47 @@ static int foreach_libblock_remap_callback(LibraryIDLinkCallbackData *cb_data)
   return IDWALK_RET_NOP;
 }
 
-static void libblock_remap_data_preprocess(IDRemap *r_id_remap_data)
+static void libblock_remap_data_preprocess_ob(Object *ob,
+                                              eIDRemapType remap_type,
+                                              const struct IDRemapper *id_remapper)
+{
+  if (ob->type != OB_ARMATURE) {
+    return;
+  }
+  if (ob->pose == NULL) {
+    return;
+  }
+
+  const bool is_cleanup_type = remap_type == ID_REMAP_TYPE_CLEANUP;
+  /* Early exit when mapping, but no armature mappings present. */
+  if (!is_cleanup_type && !BKE_id_remapper_has_mapping_for(id_remapper, FILTER_ID_AR)) {
+    return;
+  }
+
+  /* Object's pose holds reference to armature bones. sic */
+  /* Note that in theory, we should have to bother about linked/non-linked/never-null/etc.
+   * flags/states.
+   * Fortunately, this is just a tag, so we can accept to 'over-tag' a bit for pose recalc,
+   * and avoid another complex and risky condition nightmare like the one we have in
+   * foreach_libblock_remap_callback(). */
+  const IDRemapperApplyResult expected_mapping_result = BKE_id_remapper_get_mapping_result(
+      id_remapper, ob->data, ID_REMAP_APPLY_DEFAULT, NULL);
+  if (is_cleanup_type || expected_mapping_result == ID_REMAP_RESULT_SOURCE_REMAPPED) {
+    ob->pose->flag |= POSE_RECALC;
+    /* We need to clear pose bone pointers immediately, some code may access those before
+     * pose is actually recomputed, which can lead to segfault. */
+    BKE_pose_clear_pointers(ob->pose);
+  }
+}
+
+static void libblock_remap_data_preprocess(ID *id_owner,
+                                           eIDRemapType remap_type,
+                                           const struct IDRemapper *id_remapper)
 {
-  switch (GS(r_id_remap_data->id_owner->name)) {
+  switch (GS(id_owner->name)) {
     case ID_OB: {
-      ID *old_id = r_id_remap_data->old_id;
-      if (!old_id || GS(old_id->name) == ID_AR) {
-        Object *ob = (Object *)r_id_remap_data->id_owner;
-        /* Object's pose holds reference to armature bones. sic */
-        /* Note that in theory, we should have to bother about linked/non-linked/never-null/etc.
-         * flags/states.
-         * Fortunately, this is just a tag, so we can accept to 'over-tag' a bit for pose recalc,
-         * and avoid another complex and risky condition nightmare like the one we have in
-         * foreach_libblock_remap_callback(). */
-        if (ob->pose && (!old_id || ob->data == old_id)) {
-          BLI_assert(ob->type == OB_ARMATURE);
-          ob->pose->flag |= POSE_RECALC;
-          /* We need to clear pose bone pointers immediately, some code may access those before
-           * pose is actually recomputed, which can lead to segfault. */
-          BKE_pose_clear_pointers(ob->pose);
-        }
-      }
+      Object *ob = (Object *)id_owner;
+      libblock_remap_data_preprocess_ob(ob, remap_type, id_remapper);
       break;
     }
     default:
@@ -369,6 +397,37 @@ static void libblock_remap_data_postprocess_nodetree_update(Main *bmain, ID *new
   ntreeUpdateAllUsers(bmain, new_id);
 }
 
+static void libblock_remap_data_update_tags(ID *old_id, ID *new_id, void *user_data)
+{
+  IDRemap *id_remap_data = user_data;
+  const int remap_flags = id_remap_data->flag;
+  if ((remap_flags & ID_REMAP_SKIP_USER_CLEAR) == 0) {
+    /* XXX We may not want to always 'transfer' fake-user from old to new id...
+     *     Think for now it's desired behavior though,
+     *     we can always add an option (flag) to control this later if needed. */
+    if (old_id && (old_id->flag & LIB_FAKEUSER)) {
+      id_fake_user_clear(old_id);
+      id_fake_user_set(new_id);
+    }
+
+    id_us_clear_real(old_id);
+  }
+
+  if (new_id && (new_id->tag & LIB_TAG_INDIRECT) &&
+      (new_id->runtime.remap.status & ID_REMAP_IS_LINKED_DIRECT)) {
+    new_id->tag &= ~LIB_TAG_INDIRECT;
+    new_id->flag &= ~LIB_INDIRECT_WEAK_LINK;
+    new_id->tag |= LIB_TAG_EXTERN;
+  }
+}
+
+static void libblock_remap_reset_remapping_status_callback(ID *old_id,
+                                                           ID *UNUSED(new_id),
+                                                           void *UNUSED(user_data))
+{
+  BKE_libblock_runtime_reset_remapping_status(old_id);
+}
+
 /**
  * Execute the 'data' part of the remapping (that is, all ID pointers from other ID data-blocks).
  *
@@ -392,35 +451,33 @@ static void libblock_remap_data_postprocess_nodetree_update(Main *bmain, ID *new
  * (uselful to retrieve info about remapping process).
  */
 ATTR_NONNULL(1)
-static void libblock_remap_data(
-    Main *bmain, ID *id, ID *old_id, ID *new_id, const short remap_flags, IDRemap *r_id_remap_data)
+static void libblock_remap_data(Main *bmain,
+                                ID *id,
+                                eIDRemapType remap_type,
+                                struct IDRemapper *id_remapper,
+                                const short remap_flags)
 {
-  IDRemap id_remap_data;
+  IDRemap id_remap_data = {0};
   const int foreach_id_flags = ((remap_flags & ID_REMAP_FORCE_INTERNAL_RUNTIME_POINTERS) != 0 ?
                                     IDWALK_DO_INTERNAL_RUNTIME_POINTERS :
                                     IDWALK_NOP);
 
-  if (r_id_remap_data == NULL) {
-    r_id_remap_data = &id_remap_data;
-  }
-  r_id_remap_data->bmain = bmain;
-  r_id_remap_data->old_id = old_id;
-  r_id_remap_data->new_id = new_id;
-  r_id_remap_data->id_owner = NULL;
-  r_id_remap_data->flag = remap_flags;
-  r_id_remap_data->status = 0;
-  r_id_remap_data->skipped_direct = 0;
-  r_id_remap_data->skipped_indirect = 0;
-  r_id_remap_data->skipped_refcounted = 0;
+  id_remap_data.id_remapper = id_remapper;
+  id_remap_data.type = remap_type;
+  id_remap_data.bmain = bmain;
+  id_remap_data.id_owner = NULL;
+  id_remap_data.flag = remap_flags;
+
+  BKE_id_remapper_iter(id_remapper, libblock_remap_reset_remapping_status_callback, NULL);
 
   if (id) {
 #ifdef DEBUG_PRINT
     printf("\tchecking id %s (%p, %p)\n", id->name, id, id->lib);
 #endif
-    r_id_remap_data->id_owner = id;
-    libblock_remap_data_preprocess(r_id_remap_data);
+    id_remap_data.id_owner = id;
+    libblock_remap_data_preprocess(id_remap_data.id_owner, remap_type, id_remapper);
     BKE_library_foreach_ID_link(
-        NULL, id, foreach_libblock_remap_callback, (void *)r_id_remap_data, foreach_id_flags);
+        NULL, id, foreach_libblock_remap_callback, &id_remap_data, foreach_id_flags);
   }
   else {
     /* Note that this is a very 'brute force' approach,
@@ -429,48 +486,28 @@ static void libblock_remap_data(
     ID *id_curr;
 
     FOREACH_MAIN_ID_BEGIN (bmain, id_curr) {
-      if (BKE_library_id_can_use_idtype(id_curr, GS(old_id->name))) {
-        /* Note that we cannot skip indirect usages of old_id here (if requested),
-         * we still need to check it for the user count handling...
-         * XXX No more true (except for debug usage of those skipping counters). */
-        r_id_remap_data->id_owner = id_curr;
-        libblock_remap_data_preprocess(r_id_remap_data);
-        BKE_library_foreach_ID_link(NULL,
-                                    id_curr,
-                                    foreach_libblock_remap_callback,
-                                    (void *)r_id_remap_data,
-                                    foreach_id_flags);
+      const uint64_t can_use_filter_id = BKE_library_id_can_use_filter_id(id_curr);
+      const bool has_mapping = BKE_id_remapper_has_mapping_for(id_remapper, can_use_filter_id);
+
+      /* Continue when id_remapper doesn't have any mappings that can be used by id_curr. */
+      if (!has_mapping) {
+        continue;
       }
-    }
-    FOREACH_MAIN_ID_END;
-  }
 
-  if ((remap_flags & ID_REMAP_SKIP_USER_CLEAR) == 0) {
-    /* XXX We may not want to always 'transfer' fake-user from old to new id...
-     *     Think for now it's desired behavior though,
-     *     we can always add an option (flag) to control this later if needed. */
-    if (old_id && (old_id->flag & LIB_FAKEUSER)) {
-      id_fake_user_clear(old_id);
-      id_fake_user_set(new_id);
+      /* Note that we cannot skip indirect usages of old_id
+       * here (if requested), we still need to check it for the
+       * user count handling...
+       * XXX No more true (except for debug usage of those
+       * skipping counters). */
+      id_remap_data.id_owner = id_curr;
+      libblock_remap_data_preprocess(id_remap_data.id_owner, remap_type, id_remapper);
+      BKE_library_foreach_ID_link(
+          NULL, id_curr, foreach_libblock_remap_callback, &id_remap_data, foreach_id_flags);
     }
-
-    id_us_clear_real(old_id);
-  }
-
-  if (new_id && (new_id->tag & LIB_TAG_INDIRECT) &&
-      (r_id_remap_data->status & ID_REMAP_IS_LINKED_DIRECT)) {
-    new_id->tag &= ~LIB_TAG_INDIRECT;
-    new_id->flag &= ~LIB_INDIRECT_WEAK_LINK;
-    new_id->tag |= LIB_TAG_EXTERN;
+    FOREACH_MAIN_ID_END;
   }
 
-#ifdef DEBUG_PRINT
-  printf("%s: %d occurrences skipped (%d direct and %d indirect ones)\n",
-         __func__,
-         r_id_remap_data->skipped_direct + r_id_remap_data->skipped_indirect,
-         r_id_remap_data->skipped_direct,
-         r_id_remap_data->skipped_indirect);
-#endif
+  BKE_id_remapper_iter(id_remapper, libblock_remap_data_update_tags, &id_remap_data);
 }
 
 typedef struct LibblockRemapMultipleUserData {
@@ -484,32 +521,25 @@ static void libblock_remap_foreach_idpair_cb(ID *old_id, ID *new_id, void *user_
   Main *bmain = data->bmain;
   const short remap_flags = data->remap_flags;
 
-  IDRemap id_remap_data;
-  int skipped_direct, skipped_refcounted;
-
   BLI_assert(old_id != NULL);
   BLI_assert((new_id == NULL) || GS(old_id->name) == GS(new_id->name));
   BLI_assert(old_id != new_id);
 
-  libblock_remap_data(bmain, NULL, old_id, new_id, remap_flags, &id_remap_data);
-
   if (free_notifier_reference_cb) {
     free_notifier_reference_cb(old_id);
   }
 
-  skipped_direct = id_remap_data.skipped_direct;
-  skipped_refcounted = id_remap_data.skipped_refcounted;
-
   if ((remap_flags & ID_REMAP_SKIP_USER_CLEAR) == 0) {
     /* If old_id was used by some ugly 'user_one' stuff (like Image or Clip editors...), and user
      * count has actually been incremented for that, we have to decrease once more its user
      * count... unless we had to skip some 'user_one' cases. */
     if ((old_id->tag & LIB_TAG_EXTRAUSER_SET) &&
-        !(id_remap_data.status & ID_REMAP_IS_USER_ONE_SKIPPED)) {
+        !(old_id->runtime.remap.status & ID_REMAP_IS_USER_ONE_SKIPPED)) {
       id_us_clear_real(old_id);
     }
   }
 
+  const int skipped_refcounted = old_id->runtime.remap.skipped_refcounted;
   if (old_id->us - skipped_refcounted < 0) {
     CLOG_ERROR(&LOG,
                "Error in remapping process from '%s' (%p) to '%s' (%p): "
@@ -522,6 +552,7 @@ static void libblock_remap_foreach_idpair_cb(ID *old_id, ID *new_id, void *user_
     BLI_assert(0);
   }
 
+  const int skipped_direct = old_id->runtime.remap.skipped_direct;
   if (skipped_direct == 0) {
     /* old_id is assumed to not be used directly anymore... */
     if (old_id->lib && (old_id->tag & LIB_TAG_EXTERN)) {
@@ -567,10 +598,12 @@ static void libblock_remap_foreach_idpair_cb(ID *old_id, ID *new_id, void *user_
 
   /* Full rebuild of DEG! */
   DEG_relations_tag_update(bmain);
+
+  BKE_libblock_runtime_reset_remapping_status(old_id);
 }
 
 void BKE_libblock_remap_multiple_locked(Main *bmain,
-                                        const struct IDRemapper *mappings,
+                                        struct IDRemapper *mappings,
                                         const short remap_flags)
 {
   if (BKE_id_remapper_is_empty(mappings)) {
@@ -578,9 +611,12 @@ void BKE_libblock_remap_multiple_locked(Main *bmain,
     return;
   }
 
-  LibBlockRemapMultipleUserData user_data;
+  libblock_remap_data(bmain, NULL, ID_REMAP_TYPE_REMAP, mappings, remap_flags);
+
+  LibBlockRemapMultipleUserData user_data = {0};
   user_data.bmain = bmain;
   user_data.remap_flags = remap_flags;
+
   BKE_id_remapper_iter(mappings, libblock_remap_foreach_idpair_cb, &user_data);
 
   /* We assume editors do not hold references to their IDs... This is false in some cases
@@ -613,9 +649,7 @@ void BKE_libblock_remap(Main *bmain, void *old_idv, void *new_idv, const short r
   BKE_main_unlock(bmain);
 }
 
-void BKE_libblock_remap_multiple(Main *bmain,
-                                 const struct IDRemapper *mappings,
-                                 const short remap_flags)
+void BKE_libblock_remap_multiple(Main *bmain, struct IDRemapper *mappings, const short remap_flags)
 {
   BKE_main_lock(bmain);
 
@@ -658,17 +692,22 @@ void BKE_libblock_relink_ex(
   ID *new_id = new_idv;
 
   /* No need to lock here, we are only affecting given ID, not bmain database. */
+  struct IDRemapper *id_remapper = BKE_id_remapper_create();
+  eIDRemapType remap_type = ID_REMAP_TYPE_REMAP;
 
   BLI_assert(id);
   if (old_id) {
     BLI_assert((new_id == NULL) || GS(old_id->name) == GS(new_id->name));
     BLI_assert(old_id != new_id);
+    BKE_id_remapper_add(id_remapper, old_id, new_id);
   }
   else {
     BLI_assert(new_id == NULL);
+    remap_type = ID_REMAP_TYPE_CLEANUP;
   }
 
-  libblock_remap_data(bmain, id, old_id, new_id, remap_flags, NULL);
+  libblock_remap_data(bmain, id, remap_type, id_remapper, remap_flags);
+  BKE_id_remapper_free(id_remapper);
 
   /* Some after-process updates.
    * This is a bit ugly, but cannot see a way to avoid it.
diff --git a/source/blender/makesdna/DNA_ID.h b/source/blender/makesdna/DNA_ID.h
index afe8901ccda..c045082d569 100644
--- a/source/blender/makesdna/DNA_ID.h
+++ b/source/blender/makesdna/DNA_ID.h
@@ -330,6 +330,31 @@ enum {
 /* 2 characters for ID code and 64 for actual name */
 #define MAX_ID_NAME 66
 
+/* ID_Runtime.remapping_status */
+enum {
+  /** new_id is directly linked in current .blend. */
+  ID_REMAP_IS_LINKED_DIRECT = 1 << 0,
+  /** There was some skipped 'user_one' usages of old_id. */
+  ID_REMAP_IS_USER_ONE_SKIPPED = 1 << 1,
+};
+
+/** Status used and counters created during id-remapping. */
+typedef struct ID_Runtime_Remap {
+  /** Status during ID remapping. */
+  int status;
+  /** During ID remapping the number of skipped use cases that refcount the data-block. */
+  int skipped_refcounted;
+  /** During ID remapping the number of direct use cases that could be remapped (e.g. obdata when
+in edit mode). */
+  int skipped_direct;
+  /** During ID remapping, the number of indirect use cases that could not be remapped. */
+  int skipped_indirect;
+} ID_Runtime_Remap;
+
+typedef struct ID_Runtime {
+  ID_Runtime_Remap remap;
+} ID_Runtime;
+
 /* There's a nasty circular dependency here.... 'void *' to the rescue! I
  * really wonder why this is needed. */
 typedef struct ID {
@@ -408,6 +433,8 @@ typedef struct ID {
    * May be NULL.
    */
   struct LibraryWeakReference *library_weak_reference;
+
+  struct ID_Runtime runtime;
 } ID;
 
 /**