[wasm] [cleanup] Use {code_table} accessor for iteration

This reads much nicer than the for loop with {num_imported_functions_}
and {num_functions}, and is potentially even faster, because we access
the code table directly and not via function index.

R=mstarzinger@chromium.org

Bug: v8:7754
Change-Id: I83e5c0253d8f78c22982a79d878431ba75cfc027
Reviewed-on: https://chromium-review.googlesource.com/1090271Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#53574}

src/wasm/wasm-code-manager.cc

@@ -818,23 +818,20 @@ WasmCode* NativeModule::CloneCode(const WasmCode* original_code,
 }
 
 void NativeModule::UnpackAndRegisterProtectedInstructions() {
-  for (uint32_t i = num_imported_functions_, e = num_functions_; i < e; ++i) {
-    WasmCode* wasm_code = code(i);
+  for (WasmCode* wasm_code : code_table()) {
     if (wasm_code == nullptr) continue;
     wasm_code->RegisterTrapHandlerData();
   }
 }
 
 void NativeModule::ReleaseProtectedInstructions() {
-  for (uint32_t i = num_imported_functions_, e = num_functions_; i < e; ++i) {
-    WasmCode* wasm_code = code(i);
-    if (wasm_code->HasTrapHandlerIndex()) {
-      CHECK_LT(wasm_code->trap_handler_index(),
-               static_cast<size_t>(std::numeric_limits<int>::max()));
-      trap_handler::ReleaseHandlerData(
-          static_cast<int>(wasm_code->trap_handler_index()));
-      wasm_code->ResetTrapHandlerIndex();
-    }
+  for (WasmCode* wasm_code : code_table()) {
+    if (wasm_code == nullptr || !wasm_code->HasTrapHandlerIndex()) continue;
+    CHECK_LT(wasm_code->trap_handler_index(),
+             static_cast<size_t>(std::numeric_limits<int>::max()));
+    trap_handler::ReleaseHandlerData(
+        static_cast<int>(wasm_code->trap_handler_index()));
+    wasm_code->ResetTrapHandlerIndex();
   }
 }
 

src/wasm/wasm-objects.cc

@@ -1596,11 +1596,7 @@ void WasmCompiledModule::LogWasmCodes(Isolate* isolate) {
   if (native_module == nullptr) return;
   // TODO(titzer): we skip the logging of the import wrappers
   // here, but they should be included somehow.
-  const uint32_t num_imported_functions =
-      native_module->shared_module_data()->module()->num_imported_functions;
-  const uint32_t num_functions = native_module->num_functions();
-  for (uint32_t i = num_imported_functions; i < num_functions; i++) {
-    wasm::WasmCode* code = native_module->code(i);
+  for (wasm::WasmCode* code : native_module->code_table()) {
     if (code == nullptr) continue;
     code->LogCode(isolate);
   }