From 54bd283275124f0aa8aa4aa11fd2ed203896ba84 Mon Sep 17 00:00:00 2001
From: Thomas Lively <tlively@google.com>
Date: Fri, 12 Sep 2025 17:45:50 -0700
Subject: [PATCH] [Experimental] Do not print vtable types

---
 src/passes/Print.cpp   |  6 ++++++
 src/wasm/wasm-type.cpp | 15 +++++++++++----
 2 files changed, 17 insertions(+), 4 deletions(-)

diff --git a/src/passes/Print.cpp b/src/passes/Print.cpp
index 75c5452f238..52ccd8330be 100644
--- a/src/passes/Print.cpp
+++ b/src/passes/Print.cpp
@@ -3518,6 +3518,12 @@ void PrintSExpression::visitModule(Module* curr) {
         incIndent();
       }
     }
+    if (auto it = curr->typeNames.find(type); it != curr->typeNames.end()) {
+      auto name = it->second.name.str;
+      if (name.find(".vtable") == name.size() - 7) {
+        continue;
+      }
+    }
     doIndent(o, indent);
     o << typePrinter(type) << maybeNewLine;
   }
diff --git a/src/wasm/wasm-type.cpp b/src/wasm/wasm-type.cpp
index b54116258e8..042a4ea52f3 100644
--- a/src/wasm/wasm-type.cpp
+++ b/src/wasm/wasm-type.cpp
@@ -1919,17 +1919,24 @@ TypePrinter::print(HeapType type,
   const auto& struct_ = type.getStruct();
   os << "(struct";
   if (auto desc = type.getDescriptorType()) {
-    os << " (field $vtable ";
-    print(Type(*desc, NonNullable));
+    os << " (field $vtable";
+    // print(Type(*desc, NonNullable));
     os << ')';
   }
   for (Index i = 0; i < struct_.fields.size(); ++i) {
     // TODO: move this to the function for printing fields.
     os << " (field ";
+    bool isVTable = false;
     if (auto it = fieldNames.find(i); it != fieldNames.end()) {
-      it->second.print(os) << ' ';
+      if (it->second == Name("vtable")) {
+        isVTable = true;
+      }
+      it->second.print(os);
+    }
+    if (!isVTable) {
+      os << ' ';
+      print(struct_.fields[i]);
     }
-    print(struct_.fields[i]);
     os << ')';
   }
   return os << ")";