3 files changed, 23 insertions, 11 deletions

diff --git a/src/passes/Memory64Lowering.cpp b/src/passes/Memory64Lowering.cpp
index 0a58fed13..39ce1869b 100644
--- a/src/passes/Memory64Lowering.cpp
+++ b/src/passes/Memory64Lowering.cpp
@@ -118,6 +118,7 @@ struct Memory64Lowering : public WalkerPass<PostWalker<Memory64Lowering>> {
 
   void visitMemory(Memory* memory) {
     // This is visited last.
+    seenMemory = true;
     if (memory->is64()) {
       memory->indexType = Type::i32;
       if (memory->hasMax() && memory->max > Memory::kMaxSize32) {
@@ -127,8 +128,12 @@ struct Memory64Lowering : public WalkerPass<PostWalker<Memory64Lowering>> {
   }
 
   void visitDataSegment(DataSegment* segment) {
-    if (segment->isPassive) {
-      // passive segments don't have any offset to adjust
+    // We assume that memories are visited after segments, so assert that here.
+    assert(!seenMemory);
+    auto& module = *getModule();
+
+    // passive segments don't have any offset to adjust
+    if (segment->isPassive || !module.getMemory(segment->memory)->is64()) {
       return;
     }
 
@@ -136,7 +141,6 @@ struct Memory64Lowering : public WalkerPass<PostWalker<Memory64Lowering>> {
       c->value = Literal(static_cast<uint32_t>(c->value.geti64()));
       c->type = Type::i32;
     } else if (auto* get = segment->offset->dynCast<GlobalGet>()) {
-      auto& module = *getModule();
       auto* g = module.getGlobal(get->name);
       if (g->imported() && g->base == MEMORY_BASE) {
         ImportInfo info(module);
@@ -170,6 +174,8 @@ struct Memory64Lowering : public WalkerPass<PostWalker<Memory64Lowering>> {
     super::run(module);
     module->features.disable(FeatureSet::Memory64);
   }
+
+  bool seenMemory = false;
 };
 
 Pass* createMemory64LoweringPass() { return new Memory64Lowering(); }
diff --git a/src/passes/Table64Lowering.cpp b/src/passes/Table64Lowering.cpp
index 3c4086a01..b24bea167 100644
--- a/src/passes/Table64Lowering.cpp
+++ b/src/passes/Table64Lowering.cpp
@@ -97,14 +97,19 @@ struct Table64Lowering : public WalkerPass<PostWalker<Table64Lowering>> {
 
   void visitTable(Table* table) {
     // This is visited last.
+    seenTable = true;
     if (table->is64()) {
       table->indexType = Type::i32;
     }
   }
 
   void visitElementSegment(ElementSegment* segment) {
-    if (segment->table.isNull()) {
-      // Passive segments don't have any offset to update.
+    // We assume that tables are visited after segments, so assert that here.
+    assert(!seenTable);
+    auto& module = *getModule();
+
+    // Passive segments don't have any offset to update.
+    if (segment->table.isNull() || !module.getTable(segment->table)->is64()) {
       return;
     }
 
@@ -112,7 +117,6 @@ struct Table64Lowering : public WalkerPass<PostWalker<Table64Lowering>> {
       c->value = Literal(static_cast<uint32_t>(c->value.geti64()));
       c->type = Type::i32;
     } else if (auto* get = segment->offset->dynCast<GlobalGet>()) {
-      auto& module = *getModule();
       auto* g = module.getGlobal(get->name);
       if (g->imported() && g->base == TABLE_BASE) {
         ImportInfo info(module);
@@ -138,6 +142,8 @@ struct Table64Lowering : public WalkerPass<PostWalker<Table64Lowering>> {
       WASM_UNREACHABLE("unexpected elem offset");
     }
   }
+
+  bool seenTable = false;
 };
 
 Pass* createTable64LoweringPass() { return new Table64Lowering(); }
diff --git a/src/wasm-traversal.h b/src/wasm-traversal.h
index c8078164b..8e99749b6 100644
--- a/src/wasm-traversal.h
+++ b/src/wasm-traversal.h
@@ -256,18 +256,18 @@ struct Walker : public VisitorType {
         self->walkTag(curr.get());
       }
     }
-    for (auto& curr : module->tables) {
-      self->walkTable(curr.get());
-    }
     for (auto& curr : module->elementSegments) {
       self->walkElementSegment(curr.get());
     }
-    for (auto& curr : module->memories) {
-      self->walkMemory(curr.get());
+    for (auto& curr : module->tables) {
+      self->walkTable(curr.get());
     }
     for (auto& curr : module->dataSegments) {
       self->walkDataSegment(curr.get());
     }
+    for (auto& curr : module->memories) {
+      self->walkMemory(curr.get());
+    }
   }
 
   // Walks module-level code, that is, code that is not in functions.