[wasm-split] Support Table::init

src/ir/module-splitting.cpp

@@ -729,29 +729,6 @@ void ModuleSplitter::shareImportableItems() {
     }
 
     NameCollector collector(used);
-    // We shouldn't use collector.walkModuleCode here, because we don't want to
-    // walk global initializers. At this point, all globals are still in the
-    // primary module, so if we walk global initializers here, other globals
-    // appearing in their initializers will all be marked as used in the primary
-    // module, which is not what we want.
-    //
-    // For example, we have (global $a i32 (global.get $b)). Because $a is at
-    // this point still in the primary module, $b will be marked as "used" in
-    // the primary module. But $a can be moved to a secondary module later if it
-    // is used exclusively by that module. Then $b can be also moved, in case it
-    // doesn't have other uses. But if it is marked as "used" in the primary
-    // module, it can't.
-    walkSegments(collector, &module);
-    for (auto& segment : module.dataSegments) {
-      if (segment->isActive()) {
-        used.memories.insert(segment->memory);
-      }
-    }
-    for (auto& segment : module.elementSegments) {
-      if (segment->isActive()) {
-        used.tables.insert(segment->table);
-      }
-    }
 
     // If primary module has exports, they are "used" in it. Secondary modules
     // don't have exports, so this only applies to the primary module.
@@ -785,6 +762,37 @@ void ModuleSplitter::shareImportableItems() {
       }
     }
 
+    // We shouldn't use collector.walkModuleCode here, because we don't want to
+    // walk global initializers. At this point, all globals are still in the
+    // primary module, so if we walk global initializers here, other globals
+    // appearing in their initializers will all be marked as used in the primary
+    // module, which is not what we want.
+    //
+    // For example, we have (global $a i32 (global.get $b)). Because $a is at
+    // this point still in the primary module, $b will be marked as "used" in
+    // the primary module. But $a can be moved to a secondary module later if it
+    // is used exclusively by that module. Then $b can be also moved, in case it
+    // doesn't have other uses. But if it is marked as "used" in the primary
+    // module, it can't.
+    walkSegments(collector, &module);
+    for (auto& segment : module.dataSegments) {
+      if (segment->isActive()) {
+        used.memories.insert(segment->memory);
+      }
+    }
+    for (auto& segment : module.elementSegments) {
+      if (segment->isActive()) {
+        used.tables.insert(segment->table);
+      }
+    }
+    for (auto name : used.tables) {
+      if (auto* table = primary.getTableOrNull(name)) {
+        if (table->init) {
+          collector.walk(table->init);
+        }
+      }
+    }
+
     // Compute the transitive closure of globals referenced in other globals'
     // initializers. Since globals can reference other globals, we must ensure
     // that if a global is used in a module, all its dependencies are also

src/ir/module-utils.cpp

@@ -165,6 +165,9 @@ Table* copyTable(const Table* table, Module& out) {
   ret->initial = table->initial;
   ret->max = table->max;
   ret->addressType = table->addressType;
+  if (table->init) {
+    ret->init = ExpressionManipulator::copy(table->init, out);
+  }
 
   return out.addTable(std::move(ret));
 }

test/lit/wasm-split/split-module-items.wast

@@ -9,14 +9,15 @@
 ;;    the secondary module
 
 (module
+ (import "env" "g" (global $import-global-for-table funcref))
  (memory $keep-memory 1 1)
  (global $keep-global i32 (i32.const 20))
  (table $keep-table 1 1 funcref)
  (tag $keep-tag (param i32))
 
  (memory $split-memory 1 1)
  (global $split-global i32 (i32.const 20))
- (table $split-table 1 1 funcref)
+ (table $split-table 1 1 funcref (global.get $import-global-for-table))
  (tag $split-tag (param i32))
 
  (memory $shared-memory 1 1)
@@ -44,13 +45,14 @@
  ;; SECONDARY:      (import "primary" "memory" (memory $shared-memory 1 1))
  ;; SECONDARY-NEXT: (import "primary" "table" (table $shared-table 1 1 funcref))
  ;; SECONDARY-NEXT: (import "primary" "table_5" (table $timport$1 1 funcref))
+ ;; SECONDARY-NEXT: (import "env" "g" (global $import-global-for-table funcref))
  ;; SECONDARY-NEXT: (import "primary" "global" (global $shared-global i32))
  ;; SECONDARY-NEXT: (import "primary" "keep" (func $keep (exact (param i32) (result i32))))
  ;; SECONDARY-NEXT: (import "primary" "tag" (tag $shared-tag (type $1) (param i32)))
 
  ;; SECONDARY:      (global $split-global i32 (i32.const 20))
  ;; SECONDARY-NEXT: (memory $split-memory 1 1)
- ;; SECONDARY-NEXT: (table $split-table 1 1 funcref)
+ ;; SECONDARY-NEXT: (table $split-table 1 1 funcref (global.get $import-global-for-table))
  ;; SECONDARY:      (tag $split-tag (type $1) (param i32))
 
  (func $keep (param i32) (result i32)