4 files changed, 52 insertions, 1 deletions
diff --git a/src/passes/Print.cpp b/src/passes/Print.cpp
index 5c2acf3f0..0577c7c02 100644
--- a/src/passes/Print.cpp
+++ b/src/passes/Print.cpp
@@ -2771,6 +2771,10 @@ struct PrintSExpression : public OverriddenVisitor<PrintSExpression> {
       doIndent(o, indent);
       o << '(';
       printMajor(o, "data ");
+      if (segment.name.is()) {
+        printName(segment.name, o);
+        o << ' ';
+      }
       if (segment.isPassive) {
         printMedium(o, "passive");
       } else {
diff --git a/src/wasm.h b/src/wasm.h
index 0ea3ffeb7..c23819d51 100644
--- a/src/wasm.h
+++ b/src/wasm.h
@@ -1631,6 +1631,8 @@ public:
     (uint64_t(4) * 1024 * 1024 * 1024) / kPageSize;
 
   struct Segment {
+    // For use in name section only
+    Name name;
     bool isPassive = false;
     Expression* offset = nullptr;
     std::vector<char> data; // TODO: optimize
diff --git a/src/wasm/wasm-binary.cpp b/src/wasm/wasm-binary.cpp
index 314364f38..6d4689056 100644
--- a/src/wasm/wasm-binary.cpp
+++ b/src/wasm/wasm-binary.cpp
@@ -690,7 +690,31 @@ void WasmBinaryWriter::writeNames() {
     }
   }
 
-  // TODO: label, type, element and data names
+  // memory names
+  if (wasm->memory.exists) {
+    Index count = 0;
+    for (auto& seg : wasm->memory.segments) {
+      if (seg.name.is()) {
+        count++;
+      }
+    }
+
+    if (count) {
+      auto substart =
+        startSubsection(BinaryConsts::UserSections::Subsection::NameData);
+      o << U32LEB(count);
+      for (Index i = 0; i < wasm->memory.segments.size(); i++) {
+        auto& seg = wasm->memory.segments[i];
+        if (seg.name.is()) {
+          o << U32LEB(i);
+          writeEscapedName(seg.name.str);
+        }
+      }
+      finishSubsection(substart);
+    }
+  }
+
+  // TODO: label, type, and element names
   // see: https://github.com/WebAssembly/extended-name-section
 
   finishSection(start);
@@ -2566,6 +2590,20 @@ void WasmBinaryBuilder::readNames(size_t payloadLen) {
                     << std::to_string(index) << std::endl;
         }
       }
+    } else if (nameType == BinaryConsts::UserSections::Subsection::NameData) {
+      auto num = getU32LEB();
+      for (size_t i = 0; i < num; i++) {
+        auto index = getU32LEB();
+        auto rawName = getInlineString();
+        if (index < wasm.memory.segments.size()) {
+          wasm.memory.segments[i].name = rawName;
+        } else {
+          std::cerr << "warning: memory index out of bounds in name section, "
+                       "memory subsection: "
+                    << std::string(rawName.str) << " at index "
+                    << std::to_string(index) << std::endl;
+        }
+      }
     } else if (nameType == BinaryConsts::UserSections::Subsection::NameGlobal) {
       auto num = getU32LEB();
       std::set<Name> usedNames;
diff --git a/src/wasm/wasm-s-parser.cpp b/src/wasm/wasm-s-parser.cpp
index 7efb2f2fb..3bb54f0c8 100644
--- a/src/wasm/wasm-s-parser.cpp
+++ b/src/wasm/wasm-s-parser.cpp
@@ -2380,6 +2380,10 @@ void SExpressionWasmBuilder::parseData(Element& s) {
   bool isPassive = false;
   Expression* offset = nullptr;
   Index i = 1;
+  Name name;
+  if (s[i]->dollared()) {
+    name = s[i++]->str();
+  }
   if (s[i]->isStr()) {
     // data is passive or named
     if (s[i]->str() == PASSIVE) {
@@ -2394,6 +2398,9 @@ void SExpressionWasmBuilder::parseData(Element& s) {
     throw ParseException("Unexpected data items", s.line, s.col);
   }
   parseInnerData(s, s.size() - 1, offset, isPassive);
+  if (name.is()) {
+    wasm.memory.segments.back().name = name;
+  }
 }
 
 void SExpressionWasmBuilder::parseInnerData(Element& s,