[EH] Make tag's attribute encoding detail

src/binaryen-c.cpp

@@ -3352,12 +3352,10 @@ BinaryenGlobalRef BinaryenGetGlobalByIndex(BinaryenModuleRef module,
 
 BinaryenTagRef BinaryenAddTag(BinaryenModuleRef module,
                               const char* name,
-                              uint32_t attribute,
                               BinaryenType params,
                               BinaryenType results) {
   auto* ret = new Tag();
   ret->setExplicitName(name);
-  ret->attribute = attribute;
   ret->sig = Signature(Type(params), Type(results));
   ((Module*)module)->addTag(ret);
   return ret;
@@ -3423,7 +3421,6 @@ void BinaryenAddTagImport(BinaryenModuleRef module,
                           const char* internalName,
                           const char* externalModuleName,
                           const char* externalBaseName,
-                          uint32_t attribute,
                           BinaryenType params,
                           BinaryenType results) {
   auto* ret = new Tag();
@@ -4152,9 +4149,6 @@ BinaryenExpressionRef BinaryenGlobalGetInitExpr(BinaryenGlobalRef global) {
 const char* BinaryenTagGetName(BinaryenTagRef tag) {
   return ((Tag*)tag)->name.c_str();
 }
-uint32_t BinaryenTagGetAttribute(BinaryenTagRef tag) {
-  return ((Tag*)tag)->attribute;
-}
 BinaryenType BinaryenTagGetParams(BinaryenTagRef tag) {
   return ((Tag*)tag)->sig.params.getID();
 }

src/binaryen-c.h

@@ -2072,7 +2072,6 @@ BINARYEN_API void BinaryenAddTagImport(BinaryenModuleRef module,
                                        const char* internalName,
                                        const char* externalModuleName,
                                        const char* externalBaseName,
-                                       uint32_t attribute,
                                        BinaryenType params,
                                        BinaryenType results);
 
@@ -2142,7 +2141,6 @@ BINARYEN_REF(Tag);
 // Adds a tag to the module.
 BINARYEN_API BinaryenTagRef BinaryenAddTag(BinaryenModuleRef module,
                                            const char* name,
-                                           uint32_t attribute,
                                            BinaryenType params,
                                            BinaryenType results);
 // Gets a tag reference by name. Returns NULL if the tag does not exist.
@@ -2555,8 +2553,6 @@ BinaryenGlobalGetInitExpr(BinaryenGlobalRef global);
 
 // Gets the name of the specified `Tag`.
 BINARYEN_API const char* BinaryenTagGetName(BinaryenTagRef tag);
-// Gets the attribute of the specified `Tag`.
-BINARYEN_API uint32_t BinaryenTagGetAttribute(BinaryenTagRef tag);
 // Gets the parameters type of the specified `Tag`.
 BINARYEN_API BinaryenType BinaryenTagGetParams(BinaryenTagRef tag);
 // Gets the results type of the specified `Tag`.

src/ir/module-splitting.cpp

@@ -650,7 +650,6 @@ void ModuleSplitter::shareImportableItems() {
 
   for (auto& tag : primary.tags) {
     auto secondaryTag = std::make_unique<Tag>();
-    secondaryTag->attribute = tag->attribute;
     secondaryTag->sig = tag->sig;
     makeImportExport(*tag, *secondaryTag, "tag", ExternalKind::Tag);
     secondary.addTag(std::move(secondaryTag));

src/ir/module-utils.h

@@ -66,7 +66,6 @@ inline Global* copyGlobal(Global* global, Module& out) {
 inline Tag* copyTag(Tag* tag, Module& out) {
   auto* ret = new Tag();
   ret->name = tag->name;
-  ret->attribute = tag->attribute;
   ret->sig = tag->sig;
   out.addTag(ret);
   return ret;

src/js/binaryen.js-post.js

@@ -2396,8 +2396,8 @@ function wrapModule(module, self = {}) {
   self['removeElementSegment'] = function(name) {
     return preserveStack(() => Module['_BinaryenRemoveElementSegment'](module, strToStack(name)));
   };
-  self['addTag'] = function(name, attribute, params, results) {
-    return preserveStack(() => Module['_BinaryenAddTag'](module, strToStack(name), attribute, params, results));
+  self['addTag'] = function(name, params, results) {
+    return preserveStack(() => Module['_BinaryenAddTag'](module, strToStack(name), params, results));
   };
   self['getTag'] = function(name) {
     return preserveStack(() => Module['_BinaryenGetTag'](module, strToStack(name)));
@@ -2425,9 +2425,9 @@ function wrapModule(module, self = {}) {
       Module['_BinaryenAddGlobalImport'](module, strToStack(internalName), strToStack(externalModuleName), strToStack(externalBaseName), globalType, mutable)
     );
   };
-  self['addTagImport'] = function(internalName, externalModuleName, externalBaseName, attribute, params, results) {
+  self['addTagImport'] = function(internalName, externalModuleName, externalBaseName, params, results) {
     return preserveStack(() =>
-      Module['_BinaryenAddTagImport'](module, strToStack(internalName), strToStack(externalModuleName), strToStack(externalBaseName), attribute, params, results)
+      Module['_BinaryenAddTagImport'](module, strToStack(internalName), strToStack(externalModuleName), strToStack(externalBaseName), params, results)
     );
   };
   self['addExport'] = // deprecated
@@ -3212,7 +3212,6 @@ Module['getTagInfo'] = function(tag) {
     'name': UTF8ToString(Module['_BinaryenTagGetName'](tag)),
     'module': UTF8ToString(Module['_BinaryenTagImportGetModule'](tag)),
     'base': UTF8ToString(Module['_BinaryenTagImportGetBase'](tag)),
-    'attribute': Module['_BinaryenTagGetAttribute'](tag),
     'params': Module['_BinaryenTagGetParams'](tag),
     'results': Module['_BinaryenTagGetResults'](tag)
   };

src/tools/fuzzing.h

@@ -499,7 +499,6 @@ class TranslateToFuzzReader {
     Index num = upTo(3);
     for (size_t i = 0; i < num; i++) {
       auto tag = builder.makeTag(Names::getValidTagName(wasm, "tag$"),
-                                 WASM_TAG_ATTRIBUTE_EXCEPTION,
                                  Signature(getControlFlowType(), Type::none));
       wasm.addTag(std::move(tag));
     }

src/wasm-builder.h

@@ -125,11 +125,9 @@ class Builder {
     return glob;
   }
 
-  static std::unique_ptr<Tag>
-  makeTag(Name name, uint32_t attribute, Signature sig) {
+  static std::unique_ptr<Tag> makeTag(Name name, Signature sig) {
     auto tag = std::make_unique<Tag>();
     tag->name = name;
-    tag->attribute = attribute;
     tag->sig = sig;
     return tag;
   }

src/wasm.h

@@ -1801,13 +1801,8 @@ class Global : public Importable {
   bool mutable_ = false;
 };
 
-// Kinds of tag attributes.
-enum WasmTagAttribute : unsigned { WASM_TAG_ATTRIBUTE_EXCEPTION = 0x0 };
-
 class Tag : public Importable {
 public:
-  // Kind of tag. Currently only WASM_TAG_ATTRIBUTE_EXCEPTION is possible.
-  uint32_t attribute = WASM_TAG_ATTRIBUTE_EXCEPTION;
   Signature sig;
 };
 

src/wasm/wasm-binary.cpp

@@ -282,7 +282,7 @@ void WasmBinaryWriter::writeImports() {
     BYN_TRACE("write one tag\n");
     writeImportHeader(tag);
     o << U32LEB(int32_t(ExternalKind::Tag));
-    o << U32LEB(tag->attribute);
+    o << U32LEB(0); // Reserved 'attribute' field. Always 0.
     o << U32LEB(getTypeIndex(tag->sig));
   });
   if (wasm->memory.imported()) {
@@ -656,7 +656,7 @@ void WasmBinaryWriter::writeTags() {
   o << U32LEB(num);
   ModuleUtils::iterDefinedTags(*wasm, [&](Tag* tag) {
     BYN_TRACE("write one\n");
-    o << U32LEB(tag->attribute);
+    o << U32LEB(0); // Reserved 'attribute' field. Always 0.
     o << U32LEB(getTypeIndex(tag->sig));
   });
 
@@ -2071,10 +2071,9 @@ void WasmBinaryBuilder::readImports() {
       }
       case ExternalKind::Tag: {
         Name name(std::string("eimport$") + std::to_string(tagCounter++));
-        auto attribute = getU32LEB();
+        getU32LEB(); // Reserved 'attribute' field
         auto index = getU32LEB();
-        auto curr =
-          builder.makeTag(name, attribute, getSignatureByTypeIndex(index));
+        auto curr = builder.makeTag(name, getSignatureByTypeIndex(index));
         curr->module = module;
         curr->base = base;
         wasm.addTag(std::move(curr));
@@ -2908,10 +2907,9 @@ void WasmBinaryBuilder::readTags() {
   BYN_TRACE("num: " << numTags << std::endl);
   for (size_t i = 0; i < numTags; i++) {
     BYN_TRACE("read one\n");
-    auto attribute = getU32LEB();
+    getU32LEB(); // Reserved 'attribute' field
     auto typeIndex = getU32LEB();
     wasm.addTag(Builder::makeTag("tag$" + std::to_string(i),
-                                 attribute,
                                  getSignatureByTypeIndex(typeIndex)));
   }
 }

src/wasm/wasm-validator.cpp

@@ -2984,10 +2984,6 @@ static void validateTags(Module& module, ValidationInfo& info) {
                       "Module has tags (exception-handling is disabled)");
   }
   for (auto& curr : module.tags) {
-    info.shouldBeEqual(curr->attribute,
-                       (unsigned)0,
-                       curr->attribute,
-                       "Currently only attribute 0 is supported");
     info.shouldBeEqual(curr->sig.results,
                        Type(Type::none),
                        curr->name,

test/binaryen.js/exception-handling.js

@@ -19,7 +19,7 @@ var module = new binaryen.Module();
 module.setFeatures(binaryen.Features.ReferenceTypes |
                    binaryen.Features.ExceptionHandling);
 
-module.addTag("e", 0, binaryen.i32, binaryen.none);
+module.addTag("e", binaryen.i32, binaryen.none);
 
 // (try $l0
 //   (do

test/binaryen.js/kitchen-sink.js

@@ -192,7 +192,7 @@ function test_core() {
   module = new binaryen.Module();
 
   // Create a tag
-  var tag = module.addTag("a-tag", 0, binaryen.i32, binaryen.none);
+  var tag = module.addTag("a-tag", binaryen.i32, binaryen.none);
 
   // Literals and consts
 
@@ -702,7 +702,7 @@ function test_core() {
   module.addFunctionImport("an-imported", "module", "base", iF, binaryen.f32);
   module.addGlobalImport("a-global-imp", "module", "base", binaryen.i32, false);
   module.addGlobalImport("a-mut-global-imp", "module", "base", binaryen.i32, true);
-  module.addTagImport("a-tag-imp", "module", "base", 0, binaryen.i32, binaryen.none);
+  module.addTagImport("a-tag-imp", "module", "base", binaryen.i32, binaryen.none);
 
   // Exports
 
@@ -973,7 +973,7 @@ function test_binaries() {
     var adder = module.addFunction("adder", ii, binaryen.i32, [], add);
     var initExpr = module.i32.const(3);
     var global = module.addGlobal("a-global", binaryen.i32, false, initExpr)
-    var tag = module.addTag("a-tag", 0, binaryen.createType([binaryen.i32, binaryen.i32]), binaryen.none);
+    var tag = module.addTag("a-tag", binaryen.createType([binaryen.i32, binaryen.i32]), binaryen.none);
     binaryen.setDebugInfo(true); // include names section
     buffer = module.emitBinary();
     binaryen.setDebugInfo(false);
@@ -1038,7 +1038,7 @@ function test_parsing() {
   var adder = module.addFunction("adder", ii, binaryen.i32, [], add);
   var initExpr = module.i32.const(3);
   var global = module.addGlobal("a-global", binaryen.i32, false, initExpr)
-  var tag = module.addTag("a-tag", 0, binaryen.i32, binaryen.none);
+  var tag = module.addTag("a-tag", binaryen.i32, binaryen.none);
   text = module.emitText();
   module.dispose();
   module = null;

test/binaryen.js/tag.js

@@ -13,15 +13,15 @@ module.setFeatures(binaryen.Features.ReferenceTypes |
 
 var pairType = binaryen.createType([binaryen.i32, binaryen.f32]);
 
-var tag = module.addTag("a-tag", 0, binaryen.i32, binaryen.none);
+var tag = module.addTag("a-tag", binaryen.i32, binaryen.none);
 
 console.log("GetTag is equal: " + (tag === module.getTag("a-tag")));
 
 var tagInfo = binaryen.getTagInfo(tag);
 console.log("getTagInfo=" + JSON.stringify(cleanInfo(tagInfo)));
 
 module.addTagExport("a-tag", "a-tag-exp");
-module.addTagImport("a-tag-imp", "module", "base", 0, pairType, binaryen.none);
+module.addTagImport("a-tag-imp", "module", "base", pairType, binaryen.none);
 
 assert(module.validate());
 console.log(module.emitText());

test/binaryen.js/tag.js.txt

@@ -1,5 +1,5 @@
 GetTag is equal: true
-getTagInfo={"name":"a-tag","module":"","base":"","attribute":0,"params":2,"results":0}
+getTagInfo={"name":"a-tag","module":"","base":"","params":2,"results":0}
 (module
  (type $i32_=>_none (func (param i32)))
  (type $i32_f32_=>_none (func (param i32 f32)))

test/example/c-api-kitchen-sink.c

@@ -317,7 +317,7 @@ void test_core() {
   BinaryenExpressionRef i31refExpr = BinaryenI31New(module, makeInt32(module, 1));
 
   // Tags
-  BinaryenAddTag(module, "a-tag", 0, BinaryenTypeInt32(), BinaryenTypeNone());
+  BinaryenAddTag(module, "a-tag", BinaryenTypeInt32(), BinaryenTypeNone());
 
   BinaryenAddTable(module, "tab", 0, 100);