From ccec65e3d0c980bb1079fd0946f48dea069d224e Mon Sep 17 00:00:00 2001
From: Alon Zakai <alonzakai@gmail.com>
Date: Tue, 16 Aug 2016 15:40:22 -0700
Subject: some additional validations

---
 src/wasm-s-parser.h  |  5 +++++
 src/wasm-validator.h | 11 +++++++++++
 2 files changed, 16 insertions(+)

(limited to 'src')

diff --git a/src/wasm-s-parser.h b/src/wasm-s-parser.h
index 3f61b113f..a4dd60532 100644
--- a/src/wasm-s-parser.h
+++ b/src/wasm-s-parser.h
@@ -1472,7 +1472,11 @@ private:
     wasm.addGlobal(global.release());
   }
 
+  bool seenTable = false;
+
   void parseTable(Element& s) {
+    seenTable = true;
+
     if (s.size() == 1) return; // empty table in old notation
     if (!s[1]->dollared()) {
       if (s[1]->str() == ANYFUNC) {
@@ -1495,6 +1499,7 @@ private:
   }
 
   void parseElem(Element& s) {
+    if (!seenTable) throw ParseException("elem without table", s.line, s.col);
     Index i = 1;
     Expression* offset;
     if (s[i]->isList()) {
diff --git a/src/wasm-validator.h b/src/wasm-validator.h
index 0c3acaf6d..ffdd2a2b7 100644
--- a/src/wasm-validator.h
+++ b/src/wasm-validator.h
@@ -347,10 +347,21 @@ public:
     }
     returnType = unreachable;
   }
+
+  bool isConstant(Expression* curr) {
+    return curr->is<Const>();
+  }
+
   void visitMemory(Memory *curr) {
     shouldBeFalse(curr->initial > curr->max, "memory", "memory max >= initial");
     shouldBeTrue(curr->max <= Memory::kMaxSize, "memory", "max memory must be <= 4GB");
   }
+  void visitTable(Table* curr) {
+    for (auto& segment : curr->segments) {
+      shouldBeEqual(segment.offset->type, i32, segment.offset, "segment offset should be i32");
+      shouldBeTrue(isConstant(segment.offset), segment.offset, "segment offset should be constant");
+    }
+  }
   void visitModule(Module *curr) {
     // exports
     std::set<Name> exportNames;
-- 
cgit v1.2.3