[wasm64] Fix wasm-ctor-eval + utils on 64-bit indexes for memory64 (#7059)

Some places assumed a 32-bit index.

2 files changed, 12 insertions, 5 deletions

diff --git a/src/ir/memory-utils.cpp b/src/ir/memory-utils.cpp
index 0f6b77602..552e4ff9a 100644
--- a/src/ir/memory-utils.cpp
+++ b/src/ir/memory-utils.cpp
@@ -21,8 +21,12 @@
 namespace wasm::MemoryUtils {
 
 bool flatten(Module& wasm) {
+  // If there are no memories then they are already flat, in the empty sense.
+  if (wasm.memories.empty()) {
+    return true;
+  }
   // Flatten does not currently have support for multimemory
-  if (wasm.memories.size() > 1) {
+  if (wasm.memories.size() != 1) {
     return false;
   }
   // The presence of any instruction that cares about segment identity is a
@@ -105,7 +109,8 @@ bool flatten(Module& wasm) {
     }
     std::copy(segment->data.begin(), segment->data.end(), data.begin() + start);
   }
-  dataSegments[0]->offset->cast<Const>()->value = Literal(int32_t(0));
+  dataSegments[0]->offset->cast<Const>()->value =
+    Literal::makeFromInt32(0, wasm.memories[0]->indexType);
   dataSegments[0]->data.swap(data);
   wasm.removeDataSegments(
     [&](DataSegment* curr) { return curr->name != dataSegments[0]->name; });
diff --git a/src/tools/wasm-ctor-eval.cpp b/src/tools/wasm-ctor-eval.cpp
index 72ad459d3..499c1bf6c 100644
--- a/src/tools/wasm-ctor-eval.cpp
+++ b/src/tools/wasm-ctor-eval.cpp
@@ -508,12 +508,14 @@ private:
   void applyMemoryToModule() {
     // Memory must have already been flattened into the standard form: one
     // segment at offset 0, or none.
+    auto& memory = wasm->memories[0];
     if (wasm->dataSegments.empty()) {
       Builder builder(*wasm);
       auto curr = builder.makeDataSegment();
-      curr->offset = builder.makeConst(int32_t(0));
+      curr->offset =
+        builder.makeConst(Literal::makeFromInt32(0, memory->indexType));
       curr->setName(Name::fromInt(0), false);
-      curr->memory = wasm->memories[0]->name;
+      curr->memory = memory->name;
       wasm->addDataSegment(std::move(curr));
     }
     auto& segment = wasm->dataSegments[0];
@@ -521,7 +523,7 @@ private:
 
     // Copy the current memory contents after execution into the Module's
     // memory.
-    segment->data = memories[wasm->memories[0]->name];
+    segment->data = memories[memory->name];
   }
 
   // Serializing GC data requires more work than linear memory, because