search chunks only grow while resolving libraries, so revisit only symbols appended since this library's last search

src/linker/lnk.c

@@ -1647,13 +1647,20 @@ THREAD_POOL_TASK_FUNC(lnk_search_lib_task)
   LNK_LibMemberInfo    *lib_member_infos = task->lib_member_infos;
   LNK_LibMemberRefList *member_ref_list  = &task->member_ref_lists[task_id];
 
-  for EachNode(c, LNK_SymbolHashTrieChunk, symtab->search_chunks[task_id].first) {
-    for EachIndex(i, c->count) {
-      LNK_Symbol *symbol = c->v[i].symbol;
+  LNK_SymbolHashTrieChunk *start_chunk = task->reset_search_cursor ? 0 : lib->search_cursor_chunks[task_id];
+  U64                      start_idx   = task->reset_search_cursor ? 0 : lib->search_cursor_indices[task_id];
+  LNK_SymbolHashTrieChunk *end_chunk   = symtab->search_chunks[task_id].last;
+  U64                      end_count   = end_chunk ? end_chunk->count : 0;
 
+  for EachNode(c, LNK_SymbolHashTrieChunk, start_chunk ? start_chunk : symtab->search_chunks[task_id].first) {
+    U64 i_begin = (c == start_chunk) ? start_idx : 0;
+    U64 i_end   = (c == end_chunk)   ? end_count : c->count;
+    for (U64 i = i_begin; i < i_end; i += 1) {
+      LNK_Symbol                *symbol        = c->v[i].symbol;
       LNK_ObjSymbolRef           symbol_ref    = lnk_ref_from_symbol(symbol);
       COFF_ParsedSymbol          symbol_parsed = lnk_parsed_from_symbol(symbol);
       COFF_SymbolValueInterpType symbol_interp = coff_interp_from_parsed_symbol(symbol_parsed);
+
       if (symbol_interp == COFF_SymbolValueInterp_Undefined) {
         U32 member_idx;
         if (lnk_search_lib(lib, symbol->name, &member_idx)) {
@@ -1684,6 +1691,10 @@ THREAD_POOL_TASK_FUNC(lnk_search_lib_task)
       }
     }
   }
+
+  // cache search cursors
+  lib->search_cursor_chunks[task_id]  = end_chunk;
+  lib->search_cursor_indices[task_id] = end_count;
 }
 
 internal LNK_Lib *
@@ -1819,19 +1830,32 @@ lnk_link_inputs(TP_Context      *tp,
           for EachIndex(member_idx, lib->member_count) {
             lnk_queue_lib_member(arena->v[0], &imports_hm, link->lib_member_infos_hm, &member_ref_lists[0], null_symbol, lib, lib_member_infos, member_idx);
           }
-        } else {
-          // search symbols in lib
+        } else { // search symbols in lib
           MemoryZeroTyped(member_ref_lists, tp->worker_count);
+
+          // anti-dep mode changes which weak symbols can resolve from this lib
+          B32 reset_search_cursor = lib->search_cursor_chunks != 0 && lib->searched_anti_deps != search_anti_deps;
+
+          // lazy alloc cursors for tracking searched symbols
+          if (lib->search_cursor_chunks == 0) {
+            lib->search_cursor_chunks  = push_array(link->arena, LNK_SymbolHashTrieChunk *, tp->worker_count);
+            lib->search_cursor_indices = push_array(link->arena, U64,                       tp->worker_count);
+          }
+
           LNK_SearchLibTask search_task = {
-            .search_anti_deps = search_anti_deps,
-            .link             = link,
-            .imports_hm       = &imports_hm,
-            .lib              = lib,
-            .symtab           = symtab,
-            .lib_member_infos = lib_member_infos,
-            .member_ref_lists = member_ref_lists
+            .search_anti_deps    = search_anti_deps,
+            .reset_search_cursor = reset_search_cursor,
+            .link                = link,
+            .imports_hm          = &imports_hm,
+            .lib                 = lib,
+            .symtab              = symtab,
+            .lib_member_infos    = lib_member_infos,
+            .member_ref_lists    = member_ref_lists
           };
           tp_for_parallel(tp, arena, tp->worker_count, lnk_search_lib_task, &search_task);
+
+          // cache last search mode, if the mode changes then skipped weak anti-dependency must be searched again
+          lib->searched_anti_deps = search_anti_deps;
         }
 
         LNK_LibMemberRefList queued_members = {0};

src/linker/lnk.h

@@ -205,6 +205,7 @@ typedef struct LNK_BaseRelocPageArray
 typedef struct
 {
   B32                   search_anti_deps;
+  B32                   reset_search_cursor;
   LNK_Link             *link;
   HashMap              *imports_hm;
   LNK_SymbolTable      *symtab;
@@ -410,4 +411,3 @@ internal LNK_ImageContext lnk_build_image(TP_Arena *arena, TP_Context *tp, LNK_C
 
 internal void lnk_log_link_stats(LNK_ObjList obj_list, LNK_LibList *lib_index, LNK_SectionTable *sectab);
 internal void lnk_log_timers(void);
-

src/linker/lnk_lib.h

@@ -15,6 +15,10 @@ typedef struct LNK_Lib
   String8Array         symbol_names;
   String8              long_names;
   U64                  input_idx;
+  
+  struct LNK_SymbolHashTrieChunk **search_cursor_chunks;
+  U64                             *search_cursor_indices;
+  B32                              searched_anti_deps;
 } LNK_Lib;
  
 typedef struct LNK_LibNode