LibOverride: increase speed of RNA diffing process.

By using own path construction instead of handy printf-like functions,
we get a 10% improvement on overall diffing process!

This remains way to slow on some complex production characters, but
always good to have still.

6 files changed, 119 insertions, 36 deletions

diff --git a/source/blender/blenkernel/intern/lib_override.c b/source/blender/blenkernel/intern/lib_override.c
index d6f037f64a4..c37ba35991e 100644
--- a/source/blender/blenkernel/intern/lib_override.c
+++ b/source/blender/blenkernel/intern/lib_override.c
@@ -649,6 +649,7 @@ bool BKE_lib_override_library_status_check_local(Main *bmain, ID *local)
                                    &rnaptr_local,
                                    &rnaptr_reference,
                                    NULL,
+                                   0,
                                    local->override_library,
                                    RNA_OVERRIDE_COMPARE_IGNORE_NON_OVERRIDABLE |
                                        RNA_OVERRIDE_COMPARE_IGNORE_OVERRIDDEN,
@@ -712,6 +713,7 @@ bool BKE_lib_override_library_status_check_reference(Main *bmain, ID *local)
                                    &rnaptr_local,
                                    &rnaptr_reference,
                                    NULL,
+                                   0,
                                    local->override_library,
                                    RNA_OVERRIDE_COMPARE_IGNORE_OVERRIDDEN,
                                    NULL)) {
@@ -771,6 +773,7 @@ bool BKE_lib_override_library_operations_create(Main *bmain,
                                 &rnaptr_local,
                                 &rnaptr_reference,
                                 NULL,
+                                0,
                                 local->override_library,
                                 RNA_OVERRIDE_COMPARE_CREATE | RNA_OVERRIDE_COMPARE_RESTORE,
                                 &report_flags);
diff --git a/source/blender/makesrna/RNA_access.h b/source/blender/makesrna/RNA_access.h
index 65c43ebc151..7247f468245 100644
--- a/source/blender/makesrna/RNA_access.h
+++ b/source/blender/makesrna/RNA_access.h
@@ -1465,6 +1465,7 @@ bool RNA_struct_override_matches(struct Main *bmain,
                                  struct PointerRNA *ptr_local,
                                  struct PointerRNA *ptr_reference,
                                  const char *root_path,
+                                 const size_t root_path_len,
                                  struct IDOverrideLibrary *override,
                                  const eRNAOverrideMatch flags,
                                  eRNAOverrideMatchResult *r_report_flags);
diff --git a/source/blender/makesrna/intern/rna_access_compare_override.c b/source/blender/makesrna/intern/rna_access_compare_override.c
index 265e83ddcba..28ee5eca723 100644
--- a/source/blender/makesrna/intern/rna_access_compare_override.c
+++ b/source/blender/makesrna/intern/rna_access_compare_override.c
@@ -18,6 +18,8 @@
  * \ingroup RNA
  */
 
+#include <string.h>
+
 #include "MEM_guardedalloc.h"
 
 #include "DNA_ID.h"
@@ -28,7 +30,7 @@
 #include "BLI_string.h"
 #include "BLI_utildefines.h"
 
-// #define DEBUG_OVERRIDE_TIMEIT
+//#define DEBUG_OVERRIDE_TIMEIT
 
 #ifdef DEBUG_OVERRIDE_TIMEIT
 #  include "PIL_time_utildefines.h"
@@ -180,6 +182,7 @@ static int rna_property_override_diff(Main *bmain,
                                       PropertyRNA *prop_a,
                                       PropertyRNA *prop_b,
                                       const char *rna_path,
+                                      const size_t rna_path_len,
                                       eRNACompareMode mode,
                                       IDOverrideLibrary *override,
                                       const int flags,
@@ -191,7 +194,7 @@ bool RNA_property_equals(
   BLI_assert(ELEM(mode, RNA_EQ_STRICT, RNA_EQ_UNSET_MATCH_ANY, RNA_EQ_UNSET_MATCH_NONE));
 
   return (rna_property_override_diff(
-              bmain, ptr_a, ptr_b, prop, NULL, NULL, NULL, mode, NULL, 0, NULL) == 0);
+              bmain, ptr_a, ptr_b, prop, NULL, NULL, NULL, 0, mode, NULL, 0, NULL) == 0);
 }
 
 bool RNA_struct_equals(Main *bmain, PointerRNA *ptr_a, PointerRNA *ptr_b, eRNACompareMode mode)
@@ -249,6 +252,7 @@ static int rna_property_override_diff(Main *bmain,
                                       PropertyRNA *prop_a,
                                       PropertyRNA *prop_b,
                                       const char *rna_path,
+                                      const size_t rna_path_len,
                                       eRNACompareMode mode,
                                       IDOverrideLibrary *override,
                                       const int flags,
@@ -363,6 +367,7 @@ static int rna_property_override_diff(Main *bmain,
                                  mode,
                                  override,
                                  rna_path,
+                                 rna_path_len,
                                  diff_flags,
                                  &override_changed);
   if (override_changed && r_report_flags) {
@@ -568,6 +573,7 @@ bool RNA_struct_override_matches(Main *bmain,
                                  PointerRNA *ptr_local,
                                  PointerRNA *ptr_reference,
                                  const char *root_path,
+                                 const size_t root_path_len,
                                  IDOverrideLibrary *override,
                                  const eRNAOverrideMatch flags,
                                  eRNAOverrideMatchResult *r_report_flags)
@@ -649,31 +655,51 @@ bool RNA_struct_override_matches(Main *bmain,
 #endif
 
 #define RNA_PATH_BUFFSIZE 8192
-#define RNA_PATH_PRINTF(_str, ...) \
-  if (BLI_snprintf(rna_path, RNA_PATH_BUFFSIZE, (_str), __VA_ARGS__) >= RNA_PATH_BUFFSIZE) { \
-    rna_path = BLI_sprintfN((_str), __VA_ARGS__); \
-  } \
-  (void)0
-#define RNA_PATH_FREE \
-  if (rna_path != rna_path_buffer) \
-  MEM_freeN(rna_path)
 
     char rna_path_buffer[RNA_PATH_BUFFSIZE];
     char *rna_path = rna_path_buffer;
+    size_t rna_path_len = 0;
 
     /* XXX TODO this will have to be refined to handle collections insertions, and array items */
     if (root_path) {
+      BLI_assert(strlen(root_path) == root_path_len);
+
+      const char *prop_name = RNA_property_identifier(prop_local);
+      const size_t prop_name_len = strlen(prop_name);
+
       /* Inlined building, much much more efficient. */
       if (prop_local->magic == RNA_MAGIC) {
-        RNA_PATH_PRINTF("%s.%s", root_path, RNA_property_identifier(prop_local));
+        rna_path_len = root_path_len + 1 + prop_name_len;
+        if (rna_path_len >= RNA_PATH_BUFFSIZE) {
+          rna_path = MEM_mallocN(rna_path_len + 1, __func__);
+        }
+
+        memcpy(rna_path, root_path, root_path_len);
+        rna_path[root_path_len] = '.';
+        memcpy(rna_path + root_path_len + 1, prop_name, prop_name_len);
+        rna_path[rna_path_len] = '\0';
       }
       else {
-        RNA_PATH_PRINTF("%s[\"%s\"]", root_path, RNA_property_identifier(prop_local));
+        rna_path_len = root_path_len + 2 + prop_name_len + 2;
+        if (rna_path_len >= RNA_PATH_BUFFSIZE) {
+          rna_path = MEM_mallocN(rna_path_len + 1, __func__);
+        }
+
+        memcpy(rna_path, root_path, root_path_len);
+        rna_path[root_path_len] = '[';
+        rna_path[root_path_len + 1] = '"';
+        memcpy(rna_path + root_path_len + 2, prop_name, prop_name_len);
+        rna_path[root_path_len + 2 + prop_name_len] = '"';
+        rna_path[root_path_len + 2 + prop_name_len + 1] = ']';
+        rna_path[rna_path_len] = '\0';
       }
     }
     else {
       /* This is rather slow, but is not much called, so not really worth optimizing. */
       rna_path = RNA_path_from_ID_to_property(ptr_local, prop_local);
+      if (rna_path != NULL) {
+        rna_path_len = strlen(rna_path);
+      }
     }
     if (rna_path == NULL) {
       continue;
@@ -684,7 +710,10 @@ bool RNA_struct_override_matches(Main *bmain,
     IDOverrideLibraryProperty *op = BKE_lib_override_library_property_find(override, rna_path);
     if (ignore_overridden && op != NULL) {
       BKE_lib_override_library_operations_tag(op, IDOVERRIDE_LIBRARY_TAG_UNUSED, false);
-      RNA_PATH_FREE;
+
+      if (rna_path != rna_path_buffer) {
+        MEM_freeN(rna_path);
+      }
       continue;
     }
 
@@ -702,6 +731,7 @@ bool RNA_struct_override_matches(Main *bmain,
                                                 prop_local,
                                                 prop_reference,
                                                 rna_path,
+                                                rna_path_len,
                                                 RNA_EQ_STRICT,
                                                 override,
                                                 flags,
@@ -769,17 +799,18 @@ bool RNA_struct_override_matches(Main *bmain,
         matching = false;
         if (!(do_create || do_restore)) {
           /* Since we have no 'changing' action allowed, we can break here. */
-          MEM_SAFE_FREE(rna_path);
+          if (rna_path != rna_path_buffer) {
+            MEM_freeN(rna_path);
+          }
           break;
         }
       }
     }
 
-    RNA_PATH_FREE;
-
+    if (rna_path != rna_path_buffer) {
+      MEM_freeN(rna_path);
+    }
 #undef RNA_PATH_BUFFSIZE
-#undef RNA_PATH_PRINTF
-#undef RNA_PATH_FREE
   }
   RNA_property_collection_end(&iter);
 
diff --git a/source/blender/makesrna/intern/rna_internal.h b/source/blender/makesrna/intern/rna_internal.h
index 44f118a8744..0783addd78b 100644
--- a/source/blender/makesrna/intern/rna_internal.h
+++ b/source/blender/makesrna/intern/rna_internal.h
@@ -498,6 +498,7 @@ int rna_property_override_diff_default(struct Main *bmain,
                                        const int mode,
                                        struct IDOverrideLibrary *override,
                                        const char *rna_path,
+                                       const size_t rna_path_len,
                                        const int flags,
                                        bool *r_override_changed);
 
diff --git a/source/blender/makesrna/intern/rna_internal_types.h b/source/blender/makesrna/intern/rna_internal_types.h
index 0e3fc851a9b..bc83ed25ce5 100644
--- a/source/blender/makesrna/intern/rna_internal_types.h
+++ b/source/blender/makesrna/intern/rna_internal_types.h
@@ -176,6 +176,7 @@ typedef int (*RNAPropOverrideDiff)(struct Main *bmain,
                                    const int mode,
                                    struct IDOverrideLibrary *override,
                                    const char *rna_path,
+                                   const size_t rna_path_len,
                                    const int flags,
                                    bool *r_override_changed);
 
diff --git a/source/blender/makesrna/intern/rna_rna.c b/source/blender/makesrna/intern/rna_rna.c
index d7e93975d31..bf1dcfbbf25 100644
--- a/source/blender/makesrna/intern/rna_rna.c
+++ b/source/blender/makesrna/intern/rna_rna.c
@@ -1248,6 +1248,7 @@ static int rna_property_override_diff_propptr(Main *bmain,
                                               const bool no_prop_name,
                                               IDOverrideLibrary *override,
                                               const char *rna_path,
+                                              size_t rna_path_len,
                                               const char *rna_itemname_a,
                                               const char *rna_itemname_b,
                                               const int rna_itemindex_a,
@@ -1324,16 +1325,7 @@ static int rna_property_override_diff_propptr(Main *bmain,
 
       char extended_rna_path_buffer[RNA_PATH_BUFFSIZE];
       char *extended_rna_path = extended_rna_path_buffer;
-
-#  define RNA_PATH_PRINTF(_str, ...) \
-    if (BLI_snprintf(extended_rna_path_buffer, RNA_PATH_BUFFSIZE, (_str), __VA_ARGS__) >= \
-        RNA_PATH_BUFFSIZE - 1) { \
-      extended_rna_path = BLI_sprintfN((_str), __VA_ARGS__); \
-    } \
-    (void)0
-#  define RNA_PATH_FREE() \
-    if (extended_rna_path != extended_rna_path_buffer && extended_rna_path != rna_path) \
-    MEM_freeN(extended_rna_path)
+      size_t extended_rna_path_len = 0;
 
       /* There may be a propname defined in some cases, while no actual name set
        * (e.g. happens with point cache), in that case too we want to fall back to index.
@@ -1342,31 +1334,82 @@ static int rna_property_override_diff_propptr(Main *bmain,
         if ((rna_itemname_a != NULL && rna_itemname_a[0] != '\0') &&
             (rna_itemname_b != NULL && rna_itemname_b[0] != '\0')) {
           BLI_assert(STREQ(rna_itemname_a, rna_itemname_b));
+
           char esc_item_name[RNA_PATH_BUFFSIZE];
-          BLI_strescape(esc_item_name, rna_itemname_a, RNA_PATH_BUFFSIZE);
-          RNA_PATH_PRINTF("%s[\"%s\"]", rna_path, esc_item_name);
+          const size_t esc_item_name_len = BLI_strescape(
+              esc_item_name, rna_itemname_a, RNA_PATH_BUFFSIZE);
+          extended_rna_path_len = rna_path_len + 2 + esc_item_name_len + 2;
+          if (extended_rna_path_len >= RNA_PATH_BUFFSIZE) {
+            extended_rna_path = MEM_mallocN(extended_rna_path_len + 1, __func__);
+          }
+
+          memcpy(extended_rna_path, rna_path, rna_path_len);
+          extended_rna_path[rna_path_len] = '[';
+          extended_rna_path[rna_path_len + 1] = '"';
+          memcpy(extended_rna_path + rna_path_len + 2, esc_item_name, esc_item_name_len);
+          extended_rna_path[rna_path_len + 2 + esc_item_name_len] = '"';
+          extended_rna_path[rna_path_len + 2 + esc_item_name_len + 1] = ']';
+          extended_rna_path[extended_rna_path_len] = '\0';
         }
         else if (rna_itemindex_a != -1) { /* Based on index... */
           BLI_assert(rna_itemindex_a == rna_itemindex_b);
-          RNA_PATH_PRINTF("%s[%d]", rna_path, rna_itemindex_a);
+
+          /* low-level specific highly-efficient conversion of positive integer to string. */
+          char item_index_buff[32];
+          size_t item_index_buff_len = 0;
+          if (rna_itemindex_a == 0) {
+            item_index_buff[0] = '0';
+            item_index_buff_len = 1;
+          }
+          else {
+            uint index;
+            for (index = rna_itemindex_a;
+                 index > 0 && item_index_buff_len < sizeof(item_index_buff);
+                 index /= 10) {
+              item_index_buff[item_index_buff_len++] = '0' + (char)(index % 10);
+            }
+            BLI_assert(index == 0);
+          }
+
+          extended_rna_path_len = rna_path_len + item_index_buff_len + 2;
+          if (extended_rna_path_len >= RNA_PATH_BUFFSIZE) {
+            extended_rna_path = MEM_mallocN(extended_rna_path_len + 1, __func__);
+          }
+
+          memcpy(extended_rna_path, rna_path, rna_path_len);
+          extended_rna_path[rna_path_len] = '[';
+          for (size_t i = 1; i <= item_index_buff_len; i++) {
+            /* The first loop above generated inverted string representation of our index number.
+             */
+            extended_rna_path[rna_path_len + i] = item_index_buff[item_index_buff_len - i];
+          }
+          extended_rna_path[rna_path_len + 1 + item_index_buff_len] = ']';
+          extended_rna_path[extended_rna_path_len] = '\0';
         }
         else {
           extended_rna_path = (char *)rna_path;
+          extended_rna_path_len = rna_path_len;
         }
       }
 
       eRNAOverrideMatchResult report_flags = 0;
-      const bool match = RNA_struct_override_matches(
-          bmain, propptr_a, propptr_b, extended_rna_path, override, flags, &report_flags);
+      const bool match = RNA_struct_override_matches(bmain,
+                                                     propptr_a,
+                                                     propptr_b,
+                                                     extended_rna_path,
+                                                     extended_rna_path_len,
+                                                     override,
+                                                     flags,
+                                                     &report_flags);
       if (r_override_changed && (report_flags & RNA_OVERRIDE_MATCH_RESULT_CREATED) != 0) {
         *r_override_changed = true;
       }
 
-      RNA_PATH_FREE();
+      if (extended_rna_path != extended_rna_path_buffer && extended_rna_path != rna_path) {
+        MEM_freeN(extended_rna_path);
+      }
 
 #  undef RNA_PATH_BUFFSIZE
-#  undef RNA_PATH_PRINTF
-#  undef RNA_PATH_FREE
 
       return !match;
     }
@@ -1395,6 +1438,7 @@ int rna_property_override_diff_default(Main *bmain,
                                        const int mode,
                                        IDOverrideLibrary *override,
                                        const char *rna_path,
+                                       const size_t rna_path_len,
                                        const int flags,
                                        bool *r_override_changed)
 {
@@ -1684,6 +1728,7 @@ int rna_property_override_diff_default(Main *bmain,
                                                   no_prop_name,
                                                   override,
                                                   rna_path,
+                                                  rna_path_len,
                                                   NULL,
                                                   NULL,
                                                   -1,
@@ -1844,6 +1889,7 @@ int rna_property_override_diff_default(Main *bmain,
                                                                 no_prop_name,
                                                                 override,
                                                                 rna_path,
+                                                                rna_path_len,
                                                                 propname_a,
                                                                 propname_b,
                                                                 idx_a,