[NFC] Simplify binary reading logic for tables (#4974)

Similar to #4969 but for tables.

Author: kripken

src/wasm-binary.h

@@ -1519,11 +1519,6 @@ class WasmBinaryBuilder {
   // function to check
   Index endOfFunction = -1;
 
-  // we store tables here before wasm.addTable after we know their names
-  std::vector<std::unique_ptr<Table>> tables;
-  // we store table imports here before wasm.addTableImport after we know
-  // their names
-  std::vector<Table*> tableImports;
   // at index i we have all references to the table i
   std::map<Index, std::vector<Name*>> tableRefs;
 

src/wasm/wasm-binary.cpp

@@ -2334,7 +2334,6 @@ void WasmBinaryBuilder::readImports() {
           throwError("Tables may not be 64-bit");
         }
 
-        tableImports.push_back(table.get());
         wasm.addTable(std::move(table));
         break;
       }
@@ -2986,9 +2985,6 @@ void WasmBinaryBuilder::processNames() {
   for (auto& global : globals) {
     wasm.addGlobal(std::move(global));
   }
-  for (auto& table : tables) {
-    wasm.addTable(std::move(table));
-  }
   for (auto& segment : elementSegments) {
     wasm.addElementSegment(std::move(segment));
   }
@@ -3115,7 +3111,7 @@ void WasmBinaryBuilder::readTableDeclarations() {
       throwError("Tables may not be 64-bit");
     }
 
-    tables.push_back(std::move(table));
+    wasm.addTable(std::move(table));
   }
 }
 
@@ -3154,17 +3150,10 @@ void WasmBinaryBuilder::readElementSegments() {
         tableIdx = getU32LEB();
       }
 
-      Table* table = nullptr;
-      auto numTableImports = tableImports.size();
-      if (tableIdx < numTableImports) {
-        table = tableImports[tableIdx];
-      } else if (tableIdx - numTableImports < tables.size()) {
-        table = tables[tableIdx - numTableImports].get();
-      }
-      if (!table) {
+      if (tableIdx >= wasm.tables.size()) {
         throwError("Table index out of range.");
       }
-
+      auto* table = wasm.tables[tableIdx].get();
       segment->table = table->name;
       segment->offset = readExpression();
     }
@@ -3367,20 +3356,15 @@ void WasmBinaryBuilder::readNames(size_t payloadLen) {
         auto index = getU32LEB();
         auto rawName = getInlineString();
         auto name = processor.process(rawName);
-        auto numTableImports = tableImports.size();
-        auto setTableName = [&](Table* table) {
+
+        if (index < wasm.tables.size()) {
+          auto* table = wasm.tables[index].get();
           for (auto& segment : elementSegments) {
             if (segment->table == table->name) {
               segment->table = name;
             }
           }
           table->setExplicitName(name);
-        };
-
-        if (index < numTableImports) {
-          setTableName(tableImports[index]);
-        } else if (index - numTableImports < tables.size()) {
-          setTableName(tables[index - numTableImports].get());
         } else {
           std::cerr << "warning: table index out of bounds in name section, "
                        "table subsection: "
@@ -5226,7 +5210,7 @@ bool WasmBinaryBuilder::maybeVisitTableSize(Expression*& out, uint32_t code) {
     return false;
   }
   Index tableIdx = getU32LEB();
-  if (tableIdx >= tables.size()) {
+  if (tableIdx >= wasm.tables.size()) {
     throwError("bad table index");
   }
   auto* curr = allocator.alloc<TableSize>();
@@ -5242,7 +5226,7 @@ bool WasmBinaryBuilder::maybeVisitTableGrow(Expression*& out, uint32_t code) {
     return false;
   }
   Index tableIdx = getU32LEB();
-  if (tableIdx >= tables.size()) {
+  if (tableIdx >= wasm.tables.size()) {
     throwError("bad table index");
   }
   auto* curr = allocator.alloc<TableGrow>();
@@ -6634,11 +6618,11 @@ void WasmBinaryBuilder::visitRefEq(RefEq* curr) {
 void WasmBinaryBuilder::visitTableGet(TableGet* curr) {
   BYN_TRACE("zz node: TableGet\n");
   Index tableIdx = getU32LEB();
-  if (tableIdx >= tables.size()) {
+  if (tableIdx >= wasm.tables.size()) {
     throwError("bad table index");
   }
   curr->index = popNonVoidExpression();
-  curr->type = tables[tableIdx]->type;
+  curr->type = wasm.tables[tableIdx]->type;
   curr->finalize();
   // Defer setting the table name for later, when we know it.
   tableRefs[tableIdx].push_back(&curr->table);
@@ -6647,7 +6631,7 @@ void WasmBinaryBuilder::visitTableGet(TableGet* curr) {
 void WasmBinaryBuilder::visitTableSet(TableSet* curr) {
   BYN_TRACE("zz node: TableSet\n");
   Index tableIdx = getU32LEB();
-  if (tableIdx >= tables.size()) {
+  if (tableIdx >= wasm.tables.size()) {
     throwError("bad table index");
   }
   curr->value = popNonVoidExpression();