Introduce IKG into kernel-service to support incremental compilation.

runtime/vm/kernel_isolate.cc

Index: runtime/vm/kernel_isolate.cc
diff --git a/runtime/vm/kernel_isolate.cc b/runtime/vm/kernel_isolate.cc
index e66b58ba4eec33d913df28754005eb653c82f3cc..6e270c123ff5ec76b000d6fde822aa1e585da2c4 100644
--- a/runtime/vm/kernel_isolate.cc
+++ b/runtime/vm/kernel_isolate.cc
@@ -267,6 +267,31 @@ Dart_Port KernelIsolate::WaitForKernelPort() {
   return kernel_port_;
 }
 
+static Dart_CObject BuildFilesPairs(int source_files_count,
+                                    Dart_SourceFile source_files[]) {
+  Dart_CObject files;
+  files.type = Dart_CObject_kArray;
+  files.value.as_array.length = source_files_count * 2;
+  // typedef Dart_CObject* Dart_CObjectPtr;
+  Dart_CObject** fileNamePairs = new Dart_CObject*[source_files_count * 2];
+  for (int i = 0; i < source_files_count; i++) {
+    Dart_CObject* source_uri = new Dart_CObject();
+    source_uri->type = Dart_CObject_kString;
+    source_uri->value.as_string = const_cast<char*>(source_files[i].uri);
+    fileNamePairs[i * 2] = source_uri;
+
+    Dart_CObject* source_code = new Dart_CObject();
+    source_code->type = Dart_CObject_kTypedData;
+    source_code->value.as_typed_data.type = Dart_TypedData_kUint8;
+    source_code->value.as_typed_data.length = strlen(source_files[i].source);
+    source_code->value.as_typed_data.values =
+        reinterpret_cast<uint8_t*>(const_cast<char*>(source_files[i].source));
+    fileNamePairs[(i * 2) + 1] = source_code;
+  }
+  files.value.as_array.values = fileNamePairs;
+  return files;
+}
+
 class KernelCompilationRequest : public ValueObject {
  public:
   KernelCompilationRequest()
@@ -294,10 +319,12 @@ class KernelCompilationRequest : public ValueObject {
       Dart_Port kernel_port,
       const char* script_uri,
       int source_files_count,
-      Dart_SourceFile source_files[]) {
-    // Build the [null, send_port, script_uri] message for the Kernel isolate:
-    // null tag tells it that request came from this code, instead of Loader
-    // so that it can given a more informative response.
+      Dart_SourceFile source_files[],
+      bool incremental) {
+    // Build the [null, send_port, script_uri, incremental, isolate_id, [files]]
+    // message for the Kernel isolate: null tag tells it that request came from
+    // this code, instead of Loader so that it can given a more informative
+    // response.
     Dart_CObject tag;
     tag.type = Dart_CObject_kNull;
 
@@ -310,44 +337,30 @@ class KernelCompilationRequest : public ValueObject {
     uri.type = Dart_CObject_kString;
     uri.value.as_string = const_cast<char*>(script_uri);
 
+    Dart_CObject dart_incremental;
+    dart_incremental.type = Dart_CObject_kBool;
+    dart_incremental.value.as_bool = incremental;
+
+    Dart_CObject isolate_id;
+    isolate_id.type = Dart_CObject_kInt64;
+    isolate_id.value.as_int64 =
+        static_cast<int64_t>(Thread::Current()->isolate()->main_port());
+
     Dart_CObject message;
     message.type = Dart_CObject_kArray;
 
-    if (source_files_count == 0) {
-      static const intptr_t message_len = 3;
-      Dart_CObject* message_arr[] = {&tag, &send_port, &uri};
-      message.value.as_array.values = message_arr;
-      message.value.as_array.length = message_len;
-      // Send the message.
-      Dart_PostCObject(kernel_port, &message);
-    } else {
-      Dart_CObject files;
-      files.type = Dart_CObject_kArray;
-      files.value.as_array.length = source_files_count * 2;
-      // typedef Dart_CObject* Dart_CObjectPtr;
-      Dart_CObject** fileNamePairs = new Dart_CObject*[source_files_count * 2];
-      for (int i = 0; i < source_files_count; i++) {
-        Dart_CObject* source_uri = new Dart_CObject();
-        source_uri->type = Dart_CObject_kString;
-        source_uri->value.as_string = const_cast<char*>(source_files[i].uri);
-        fileNamePairs[i * 2] = source_uri;
-
-        Dart_CObject* source_code = new Dart_CObject();
-        source_code->type = Dart_CObject_kTypedData;
-        source_code->value.as_typed_data.type = Dart_TypedData_kUint8;
-        source_code->value.as_typed_data.length =
-            strlen(source_files[i].source);
-        source_code->value.as_typed_data.values = reinterpret_cast<uint8_t*>(
-            const_cast<char*>(source_files[i].source));
-        fileNamePairs[(i * 2) + 1] = source_code;
-      }
-      files.value.as_array.values = fileNamePairs;
-      static const intptr_t message_len = 4;
-      Dart_CObject* message_arr[] = {&tag, &send_port, &uri, &files};
-      message.value.as_array.values = message_arr;
-      message.value.as_array.length = message_len;
-      Dart_PostCObject(kernel_port, &message);
+    intptr_t message_len = 5;
+    Dart_CObject files;
+    if (source_files_count != 0) {
+      files = BuildFilesPairs(source_files_count, source_files);
+      message_len++;
     }
+    Dart_CObject* message_arr[] = {
+        &tag, &send_port, &uri, &dart_incremental, &isolate_id, &files};
+    message.value.as_array.values = message_arr;
+    message.value.as_array.length = message_len;
+    // Send the message.
+    Dart_PostCObject(kernel_port, &message);
 
     // Wait for reply to arrive.
     MonitorLocker ml(monitor_);
@@ -458,7 +471,8 @@ KernelCompilationRequest* KernelCompilationRequest::requests_ = NULL;
 Dart_KernelCompilationResult KernelIsolate::CompileToKernel(
     const char* script_uri,
     int source_file_count,
-    Dart_SourceFile source_files[]) {
+    Dart_SourceFile source_files[],
+    bool incremental) {
   // This must be the main script to be loaded. Wait for Kernel isolate
   // to finish initialization.
   Dart_Port kernel_port = WaitForKernelPort();
@@ -470,8 +484,8 @@ Dart_KernelCompilationResult KernelIsolate::CompileToKernel(
   }
 
   KernelCompilationRequest request;
-  return request.SendAndWaitForResponse(kernel_port, script_uri,
-                                        source_file_count, source_files);
+  return request.SendAndWaitForResponse(
+      kernel_port, script_uri, source_file_count, source_files, incremental);
 }
 
 #endif  // DART_PRECOMPILED_RUNTIME