Revert "Revert "Use Kernel frontend from run_vm_tests.""

runtime/bin/run_vm_tests.cc

Index: runtime/bin/run_vm_tests.cc
diff --git a/runtime/bin/run_vm_tests.cc b/runtime/bin/run_vm_tests.cc
index ed1e0969e6eef19406a84b0dfd86bf54922dd643..ddb8a4e37bb1846b32cc68cb8dade34fbce15b64 100644
--- a/runtime/bin/run_vm_tests.cc
+++ b/runtime/bin/run_vm_tests.cc
@@ -6,7 +6,9 @@
 
 #include "bin/dartutils.h"
 #include "bin/file.h"
+#include "bin/loader.h"
 #include "bin/platform.h"
+#include "bin/snapshot_utils.h"
 #include "platform/assert.h"
 #include "vm/benchmark_test.h"
 #include "vm/dart.h"
@@ -30,6 +32,7 @@ static const char* const kNone = "No Test or Benchmarks";
 static const char* const kList = "List all Tests and Benchmarks";
 static const char* const kAllBenchmarks = "All Benchmarks";
 static const char* run_filter = kNone;
+static const char* kernel_snapshot = NULL;
 
 static int run_matches = 0;
 
@@ -75,12 +78,98 @@ void Benchmark::RunBenchmark() {
 
 static void PrintUsage() {
   OS::PrintErr(
-      "run_vm_tests [--list | --benchmarks | "
-      "<test name> | <benchmark name>]\n");
-  OS::PrintErr("run_vm_tests [vm-flags ...] <test name>\n");
-  OS::PrintErr("run_vm_tests [vm-flags ...] <benchmark name>\n");
+      "Usage: one of the following\n"
+      "  run_vm_tests --list\n"
+      "  run_vm_tests [--dfe=<snapshot file name>] --benchmarks\n"
+      "  run_vm_tests [--dfe=<snapshot file name>] [vm-flags ...] <test name>\n"
+      "  run_vm_tests [--dfe=<snapshot file name>] [vm-flags ...] <benchmark "
+      "name>\n");
 }
 
+#define CHECK_RESULT(result)                                                   \
+  if (Dart_IsError(result)) {                                                  \
+    *error = strdup(Dart_GetError(result));                                    \
+    Dart_ExitScope();                                                          \
+    Dart_ShutdownIsolate();                                                    \
+    return NULL;                                                               \
+  }
+
+
+static Dart_Isolate CreateIsolateAndSetup(const char* script_uri,
+                                          const char* main,
+                                          const char* package_root,
+                                          const char* packages_config,
+                                          Dart_IsolateFlags* flags,
+                                          void* data,
+                                          char** error) {
+  ASSERT(script_uri != NULL);
+  const bool is_service_isolate =
+      strcmp(script_uri, DART_VM_SERVICE_ISOLATE_NAME) == 0;
+  if (is_service_isolate) {
+    // We don't need service isolate for VM tests.
+    return NULL;
+  }
+  const bool is_kernel_isolate =
+      strcmp(script_uri, DART_KERNEL_ISOLATE_NAME) == 0;
+  if (!is_kernel_isolate) {
+    *error =
+        strdup("Spawning of only Kernel isolate is supported in run_vm_tests.");
+    return NULL;
+  }
+  if (kernel_snapshot == NULL) {
+    *error =
+        strdup("Kernel snapshot location has to be specified via --dfe option");
+    return NULL;
+  }
+  script_uri = kernel_snapshot;
+
+  bin::AppSnapshot* app_snapshot =
+      bin::Snapshot::TryReadAppSnapshot(script_uri);
+  if (app_snapshot == NULL) {
+    *error = strdup("Failed to read kernel service app snapshot");
+    return NULL;
+  }
+
+  const uint8_t* isolate_snapshot_data = bin::core_isolate_snapshot_data;
+  const uint8_t* isolate_snapshot_instructions =
+      bin::core_isolate_snapshot_instructions;
+
+  const uint8_t* ignore_vm_snapshot_data;
+  const uint8_t* ignore_vm_snapshot_instructions;
+  app_snapshot->SetBuffers(
+      &ignore_vm_snapshot_data, &ignore_vm_snapshot_instructions,
+      &isolate_snapshot_data, &isolate_snapshot_instructions);
+
+  bin::IsolateData* isolate_data = new bin::IsolateData(
+      script_uri, package_root, packages_config, NULL /* app_snapshot */);
+  Dart_Isolate isolate = Dart_CreateIsolate(
+      script_uri, main, isolate_snapshot_data, isolate_snapshot_instructions,
+      flags, isolate_data, error);
+  if (isolate == NULL) {
+    *error = strdup("Failed to create isolate");
+    delete isolate_data;
+    return NULL;
+  }
+
+  Dart_EnterScope();
+
+  bin::DartUtils::SetOriginalWorkingDirectory();
+  Dart_Handle result = bin::DartUtils::PrepareForScriptLoading(
+      false /* is_service_isolate */, false /* trace_loading */);
+  CHECK_RESULT(result);
+
+  Dart_ExitScope();
+  Dart_ExitIsolate();
+  bool retval = Dart_IsolateMakeRunnable(isolate);
+  if (!retval) {
+    *error = strdup("Invalid isolate state - Unable to make it runnable");
+    Dart_EnterIsolate(isolate);
+    Dart_ShutdownIsolate();
+    return NULL;
+  }
+
+  return isolate;
+}
 
 static int Main(int argc, const char** argv) {
   // Flags being passed to the Dart VM.
@@ -96,20 +185,36 @@ static int Main(int argc, const char** argv) {
     // Bad parameter count.
     PrintUsage();
     return 1;
-  } else if (argc == 2) {
-    if (strcmp(argv[1], "--list") == 0) {
-      run_filter = kList;
-      // List all tests and benchmarks and exit without initializing the VM.
-      TestCaseBase::RunAll();
-      Benchmark::RunAll(argv[0]);
-      TestCaseBase::RunAllRaw();
-      fflush(stdout);
-      return 0;
-    } else if (strcmp(argv[1], "--benchmarks") == 0) {
-      run_filter = kAllBenchmarks;
-    } else {
-      run_filter = argv[1];
+  }
+
+  if (argc == 2 && strcmp(argv[1], "--list") == 0) {
+    run_filter = kList;
+    // List all tests and benchmarks and exit without initializing the VM.
+    TestCaseBase::RunAll();
+    Benchmark::RunAll(argv[0]);
+    TestCaseBase::RunAllRaw();
+    fflush(stdout);
+    return 0;
+  }
+
+  int arg_pos = 1;
+  if (strstr(argv[arg_pos], "--dfe") == argv[arg_pos]) {
+    const char* delim = strstr(argv[1], "=");
+    if (delim == NULL || strlen(delim + 1) == 0) {
+      OS::PrintErr("Invalid value for the option: %s\n", argv[1]);
+      PrintUsage();
+      return 1;
     }
+    kernel_snapshot = strdup(delim + 1);
+    // VM needs '--use-dart-frontend' option, which we will insert in place
+    // of '--dfe' option.
+    argv[arg_pos] = strdup("--use-dart-frontend");
+    ++arg_pos;
+  }
+
+  if (arg_pos == argc - 1 && strcmp(argv[arg_pos], "--benchmarks") == 0) {
+    // "--benchmarks" is the last argument.
+    run_filter = kAllBenchmarks;
   } else {
     // Last argument is the test name, the rest are vm flags.
     run_filter = argv[argc - 1];
@@ -118,14 +223,18 @@ static int Main(int argc, const char** argv) {
     dart_argc = argc - 2;
     dart_argv = &argv[1];
   }
+
   bool set_vm_flags_success =
       Flags::ProcessCommandLineFlags(dart_argc, dart_argv);
   ASSERT(set_vm_flags_success);
   const char* err_msg = Dart::InitOnce(
-      dart::bin::vm_snapshot_data, dart::bin::vm_snapshot_instructions, NULL,
-      NULL, NULL, NULL, dart::bin::DartUtils::OpenFile,
-      dart::bin::DartUtils::ReadFile, dart::bin::DartUtils::WriteFile,
-      dart::bin::DartUtils::CloseFile, NULL, NULL);
+      dart::bin::vm_snapshot_data, dart::bin::vm_snapshot_instructions,
+      CreateIsolateAndSetup /* create */, NULL /* shutdown */,
+      NULL /* cleanup */, NULL /* thread_exit */,
+      dart::bin::DartUtils::OpenFile, dart::bin::DartUtils::ReadFile,
+      dart::bin::DartUtils::WriteFile, dart::bin::DartUtils::CloseFile,
+      NULL /* entropy_source */, NULL /* get_service_assets */);
+
   ASSERT(err_msg == NULL);
   // Apply the filter to all registered tests.
   TestCaseBase::RunAll();