4 files changed, 51 insertions, 0 deletions
diff --git a/src/wasm/wasm-binary.cpp b/src/wasm/wasm-binary.cpp
index b7ffcd8d7..2c473a254 100644
--- a/src/wasm/wasm-binary.cpp
+++ b/src/wasm/wasm-binary.cpp
@@ -3005,6 +3005,9 @@ BinaryConsts::ASTNodes WasmBinaryBuilder::readExpression(Expression*& curr) {
       if (maybeVisitSIMDLoadStoreLane(curr, opcode)) {
         break;
       }
+      if (maybeVisitSIMDWiden(curr, opcode)) {
+        break;
+      }
       if (maybeVisitPrefetch(curr, opcode)) {
         break;
       }
@@ -5466,6 +5469,27 @@ bool WasmBinaryBuilder::maybeVisitSIMDLoadStoreLane(Expression*& out,
   return true;
 }
 
+bool WasmBinaryBuilder::maybeVisitSIMDWiden(Expression*& out, uint32_t code) {
+  SIMDWidenOp op;
+  switch (code) {
+    case BinaryConsts::I32x4WidenSI8x16:
+      op = WidenSVecI8x16ToVecI32x4;
+      break;
+    case BinaryConsts::I32x4WidenUI8x16:
+      op = WidenUVecI8x16ToVecI32x4;
+      break;
+    default:
+      return false;
+  }
+  auto* curr = allocator.alloc<SIMDWiden>();
+  curr->op = op;
+  curr->index = getLaneIndex(4);
+  curr->vec = popNonVoidExpression();
+  curr->finalize();
+  out = curr;
+  return true;
+}
+
 bool WasmBinaryBuilder::maybeVisitPrefetch(Expression*& out, uint32_t code) {
   PrefetchOp op;
   switch (code) {
diff --git a/src/wasm/wasm-s-parser.cpp b/src/wasm/wasm-s-parser.cpp
index 3075f70d7..0dc121f2c 100644
--- a/src/wasm/wasm-s-parser.cpp
+++ b/src/wasm/wasm-s-parser.cpp
@@ -1666,6 +1666,15 @@ SExpressionWasmBuilder::makeSIMDLoadStoreLane(Element& s,
   return ret;
 }
 
+Expression* SExpressionWasmBuilder::makeSIMDWiden(Element& s, SIMDWidenOp op) {
+  auto* ret = allocator.alloc<SIMDWiden>();
+  ret->op = op;
+  ret->index = parseLaneIndex(s[1], 4);
+  ret->vec = parseExpression(s[2]);
+  ret->finalize();
+  return ret;
+}
+
 Expression* SExpressionWasmBuilder::makePrefetch(Element& s, PrefetchOp op) {
   Address offset, align;
   size_t i = parseMemAttributes(s, offset, align, /*defaultAlign*/ 1);
diff --git a/src/wasm/wasm-stack.cpp b/src/wasm/wasm-stack.cpp
index d42080bac..cb8702d0c 100644
--- a/src/wasm/wasm-stack.cpp
+++ b/src/wasm/wasm-stack.cpp
@@ -691,6 +691,19 @@ void BinaryInstWriter::visitSIMDLoadStoreLane(SIMDLoadStoreLane* curr) {
   o << curr->index;
 }
 
+void BinaryInstWriter::visitSIMDWiden(SIMDWiden* curr) {
+  o << int8_t(BinaryConsts::SIMDPrefix);
+  switch (curr->op) {
+    case WidenSVecI8x16ToVecI32x4:
+      o << U32LEB(BinaryConsts::I32x4WidenSI8x16);
+      break;
+    case WidenUVecI8x16ToVecI32x4:
+      o << U32LEB(BinaryConsts::I32x4WidenUI8x16);
+      break;
+  }
+  o << uint8_t(curr->index);
+}
+
 void BinaryInstWriter::visitPrefetch(Prefetch* curr) {
   o << int8_t(BinaryConsts::SIMDPrefix);
   switch (curr->op) {
diff --git a/src/wasm/wasm.cpp b/src/wasm/wasm.cpp
index f8d8890ec..e9d2bf116 100644
--- a/src/wasm/wasm.cpp
+++ b/src/wasm/wasm.cpp
@@ -496,6 +496,11 @@ void SIMDLoadStoreLane::finalize() {
   }
 }
 
+void SIMDWiden::finalize() {
+  assert(vec);
+  type = vec->type == Type::unreachable ? Type::unreachable : Type::v128;
+}
+
 Index SIMDLoadStoreLane::getMemBytes() {
   switch (op) {
     case LoadLaneVec8x16: