Strings: Add initial validation checks (#5758)

This is far from comprehensive, but it checks strings being enabled for
all the instructions. Without this, the fuzzer can get confused because it
checks if code validates and then proceeds under that assumption, so
any missing validation checks can cause problems (specifically, if we have
a string.const without strings enabled then we error during writing of
the string, since we don't do the initial pass to find all strings to
deduplicate them).

1 files changed, 91 insertions, 0 deletions

diff --git a/src/wasm/wasm-validator.cpp b/src/wasm/wasm-validator.cpp
index 318657034..b92727e0e 100644
--- a/src/wasm/wasm-validator.cpp
+++ b/src/wasm/wasm-validator.cpp
@@ -469,6 +469,20 @@ public:
   template<typename ArrayInit> void visitArrayInit(ArrayInit* curr);
   void visitArrayInitData(ArrayInitData* curr);
   void visitArrayInitElem(ArrayInitElem* curr);
+  void visitStringNew(StringNew* curr);
+  void visitStringConst(StringConst* curr);
+  void visitStringMeasure(StringMeasure* curr);
+  void visitStringEncode(StringEncode* curr);
+  void visitStringConcat(StringConcat* curr);
+  void visitStringEq(StringEq* curr);
+  void visitStringAs(StringAs* curr);
+  void visitStringWTF8Advance(StringWTF8Advance* curr);
+  void visitStringWTF16Get(StringWTF16Get* curr);
+  void visitStringIterNext(StringIterNext* curr);
+  void visitStringIterMove(StringIterMove* curr);
+  void visitStringSliceWTF(StringSliceWTF* curr);
+  void visitStringSliceIter(StringSliceIter* curr);
+
   void visitFunction(Function* curr);
 
   // helpers
@@ -3042,6 +3056,83 @@ void FunctionValidator::visitArrayInitElem(ArrayInitElem* curr) {
                   "array.init_elem segment type must match destination type");
 }
 
+void FunctionValidator::visitStringNew(StringNew* curr) {
+  shouldBeTrue(!getModule() || getModule()->features.hasStrings(),
+               curr,
+               "string operations require reference-types [--enable-strings]");
+}
+
+void FunctionValidator::visitStringConst(StringConst* curr) {
+  shouldBeTrue(!getModule() || getModule()->features.hasStrings(),
+               curr,
+               "string operations require reference-types [--enable-strings]");
+}
+
+void FunctionValidator::visitStringMeasure(StringMeasure* curr) {
+  shouldBeTrue(!getModule() || getModule()->features.hasStrings(),
+               curr,
+               "string operations require reference-types [--enable-strings]");
+}
+
+void FunctionValidator::visitStringEncode(StringEncode* curr) {
+  shouldBeTrue(!getModule() || getModule()->features.hasStrings(),
+               curr,
+               "string operations require reference-types [--enable-strings]");
+}
+
+void FunctionValidator::visitStringConcat(StringConcat* curr) {
+  shouldBeTrue(!getModule() || getModule()->features.hasStrings(),
+               curr,
+               "string operations require reference-types [--enable-strings]");
+}
+
+void FunctionValidator::visitStringEq(StringEq* curr) {
+  shouldBeTrue(!getModule() || getModule()->features.hasStrings(),
+               curr,
+               "string operations require reference-types [--enable-strings]");
+}
+
+void FunctionValidator::visitStringAs(StringAs* curr) {
+  shouldBeTrue(!getModule() || getModule()->features.hasStrings(),
+               curr,
+               "string operations require reference-types [--enable-strings]");
+}
+
+void FunctionValidator::visitStringWTF8Advance(StringWTF8Advance* curr) {
+  shouldBeTrue(!getModule() || getModule()->features.hasStrings(),
+               curr,
+               "string operations require reference-types [--enable-strings]");
+}
+
+void FunctionValidator::visitStringWTF16Get(StringWTF16Get* curr) {
+  shouldBeTrue(!getModule() || getModule()->features.hasStrings(),
+               curr,
+               "string operations require reference-types [--enable-strings]");
+}
+void FunctionValidator::visitStringIterNext(StringIterNext* curr) {
+  shouldBeTrue(!getModule() || getModule()->features.hasStrings(),
+               curr,
+               "string operations require reference-types [--enable-strings]");
+}
+
+void FunctionValidator::visitStringIterMove(StringIterMove* curr) {
+  shouldBeTrue(!getModule() || getModule()->features.hasStrings(),
+               curr,
+               "string operations require reference-types [--enable-strings]");
+}
+
+void FunctionValidator::visitStringSliceWTF(StringSliceWTF* curr) {
+  shouldBeTrue(!getModule() || getModule()->features.hasStrings(),
+               curr,
+               "string operations require reference-types [--enable-strings]");
+}
+
+void FunctionValidator::visitStringSliceIter(StringSliceIter* curr) {
+  shouldBeTrue(!getModule() || getModule()->features.hasStrings(),
+               curr,
+               "string operations require reference-types [--enable-strings]");
+}
+
 void FunctionValidator::visitFunction(Function* curr) {
   if (curr->getResults().isTuple()) {
     shouldBeTrue(getModule()->features.hasMultivalue(),