3 files changed, 25 insertions, 9 deletions
diff --git a/src/wasm/wasm-binary.cpp b/src/wasm/wasm-binary.cpp
index 1ddb009cf..f43346fdb 100644
--- a/src/wasm/wasm-binary.cpp
+++ b/src/wasm/wasm-binary.cpp
@@ -1084,6 +1084,8 @@ void WasmBinaryWriter::writeFeaturesSection() {
         return BinaryConsts::UserSections::TypedFunctionReferencesFeature;
       case FeatureSet::RelaxedSIMD:
         return BinaryConsts::UserSections::RelaxedSIMDFeature;
+      case FeatureSet::ExtendedConst:
+        return BinaryConsts::UserSections::ExtendedConstFeature;
       default:
         WASM_UNREACHABLE("unexpected feature flag");
     }
@@ -3350,6 +3352,8 @@ void WasmBinaryBuilder::readFeatures(size_t payloadLen) {
       feature = FeatureSet::TypedFunctionReferences;
     } else if (name == BinaryConsts::UserSections::RelaxedSIMDFeature) {
       feature = FeatureSet::RelaxedSIMD;
+    } else if (name == BinaryConsts::UserSections::ExtendedConstFeature) {
+      feature = FeatureSet::ExtendedConst;
     } else {
       // Silently ignore unknown features (this may be and old binaryen running
       // on a new wasm).
diff --git a/src/wasm/wasm-validator.cpp b/src/wasm/wasm-validator.cpp
index 65fcc7a9d..86fc4811b 100644
--- a/src/wasm/wasm-validator.cpp
+++ b/src/wasm/wasm-validator.cpp
@@ -2767,13 +2767,21 @@ void FunctionValidator::visitFunction(Function* curr) {
   }
 }
 
-static bool checkSegmentOffset(Expression* curr, Address add, Address max) {
-  if (curr->is<GlobalGet>()) {
-    return true;
+static bool checkSegmentOffset(Expression* curr,
+                               Address add,
+                               Address max,
+                               FeatureSet features) {
+  if (!Properties::isValidInConstantExpression(curr, features)) {
+    return false;
   }
   auto* c = curr->dynCast<Const>();
   if (!c) {
-    return false;
+    // Unless the instruction is actually a const instruction, we don't
+    // currently try to evaluate it.
+    // TODO: Attempt to evaluate other expressions that might also be const
+    // such as `global.get` or more complex instruction sequences involving
+    // add/sub/mul/etc.
+    return true;
   }
   uint64_t raw = c->value.getInteger();
   if (raw > std::numeric_limits<Address::address32_t>::max()) {
@@ -2999,9 +3007,10 @@ static void validateGlobals(Module& module, ValidationInfo& info) {
     info.shouldBeTrue(
       curr->init != nullptr, curr->name, "global init must be non-null");
     assert(curr->init);
-    info.shouldBeTrue(GlobalUtils::canInitializeGlobal(curr->init),
-                      curr->name,
-                      "global init must be valid");
+    info.shouldBeTrue(
+      GlobalUtils::canInitializeGlobal(curr->init, module.features),
+      curr->name,
+      "global init must be valid");
 
     if (!info.shouldBeSubType(curr->init->type,
                               curr->type,
@@ -3066,7 +3075,8 @@ static void validateMemory(Module& module, ValidationInfo& info) {
       }
       info.shouldBeTrue(checkSegmentOffset(segment.offset,
                                            segment.data.size(),
-                                           curr.initial * Memory::kPageSize),
+                                           curr.initial * Memory::kPageSize,
+                                           module.features),
                         segment.offset,
                         "memory segment offset should be reasonable");
       if (segment.offset->is<Const>()) {
@@ -3171,7 +3181,8 @@ static void validateTables(Module& module, ValidationInfo& info) {
                          "element segment offset should be i32");
       info.shouldBeTrue(checkSegmentOffset(segment->offset,
                                            segment->data.size(),
-                                           table->initial * Table::kPageSize),
+                                           table->initial * Table::kPageSize,
+                                           module.features),
                         segment->offset,
                         "table segment offset should be reasonable");
       if (module.features.hasTypedFunctionReferences()) {
diff --git a/src/wasm/wasm.cpp b/src/wasm/wasm.cpp
index aac8b44fe..ca9691346 100644
--- a/src/wasm/wasm.cpp
+++ b/src/wasm/wasm.cpp
@@ -49,6 +49,7 @@ const char* GCFeature = "gc";
 const char* Memory64Feature = "memory64";
 const char* TypedFunctionReferencesFeature = "typed-function-references";
 const char* RelaxedSIMDFeature = "relaxed-simd";
+const char* ExtendedConstFeature = "extended-const";
 } // namespace UserSections
 } // namespace BinaryConsts