[wasm] Fix tier down on streaming with error

Recompilation for tier down should not be triggered if the module had a
compile error. This CL ensures that by moving the recompilation a bit
later in the async compilation, to a place where a compile error would
have been detected already. An added DCHECK would catch similar bugs
earlier (crashing instead of timing out).

R=ahaas@chromium.org

Bug: chromium:1160031
Change-Id: I7eb3d2921db0f28bb39e9ec6150fd98fd4b99089
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2649028
Commit-Queue: Clemens Backes <clemensb@chromium.org>
Reviewed-by: Andreas Haas <ahaas@chromium.org>
Cr-Commit-Position: refs/heads/master@{#72329}

src/wasm/module-compiler.cc

@@ -1707,6 +1707,7 @@ void RecompileNativeModule(NativeModule* native_module,
   compilation_state->InitializeRecompilation(
       tiering_state,
       [recompilation_finished_semaphore](CompilationEvent event) {
+        DCHECK_NE(CompilationEvent::kFailedCompilation, event);
         if (event == CompilationEvent::kFinishedRecompilation) {
           recompilation_finished_semaphore->Signal();
         }
@@ -1960,6 +1961,12 @@ void AsyncCompileJob::FinishCompile(bool is_after_cache_hit) {
   // We can only update the feature counts once the entire compile is done.
   compilation_state->PublishDetectedFeatures(isolate_);
 
+  // We might need to recompile the module for debugging, if the debugger was
+  // enabled while streaming compilation was running. Since handling this while
+  // compiling via streaming is tricky, we just tier down now, before publishing
+  // the module.
+  if (native_module_->IsTieredDown()) native_module_->RecompileForTiering();
+
   // Finally, log all generated code (it does not matter if this happens
   // repeatedly in case the script is shared).
   native_module_->LogWasmCodes(isolate_, module_object_->script());
@@ -2709,13 +2716,6 @@ void AsyncStreamingProcessor::OnFinishedStream(OwnedVector<uint8_t> bytes) {
   }
   const bool needs_finish = job_->DecrementAndCheckFinisherCount();
   DCHECK_IMPLIES(!has_code_section, needs_finish);
-  // We might need to recompile the module for debugging, if the debugger was
-  // enabled while streaming compilation was running. Since handling this while
-  // compiling via streaming is tricky, we just tier down now, before publishing
-  // the module.
-  if (job_->native_module_->IsTieredDown()) {
-    job_->native_module_->RecompileForTiering();
-  }
   if (needs_finish) {
     const bool failed = job_->native_module_->compilation_state()->failed();
     if (!cache_hit) {

test/cctest/wasm/test-streaming-compilation.cc

@@ -1372,6 +1372,28 @@ STREAM_TEST(TestProfilingMidStreaming) {
   cpu_profiler->Dispose();
 }
 
+STREAM_TEST(TierDownWithError) {
+  // https://crbug.com/1160031
+  StreamTester tester(isolate);
+  Isolate* i_isolate = reinterpret_cast<i::Isolate*>(isolate);
+  Zone* zone = tester.zone();
+
+  ZoneBuffer buffer(zone);
+  {
+    TestSignatures sigs;
+    WasmModuleBuilder builder(zone);
+    // Type error at i32.add.
+    builder.AddFunction(sigs.v_v())->Emit(kExprI32Add);
+    builder.WriteTo(&buffer);
+  }
+
+  i_isolate->wasm_engine()->TierDownAllModulesPerIsolate(i_isolate);
+
+  tester.OnBytesReceived(buffer.begin(), buffer.size());
+  tester.FinishStream();
+  tester.RunCompilerTasks();
+}
+
 #undef STREAM_TEST
 
 }  // namespace wasm