[view_compiler] Add end-to-end DexBuilder tests

These tests verify that code produced by DexBuilder can be loaded and run on
device. It works by introducing a new tool, dex_testcase_generator, which writes
out a couple of DEX files with test cases. This tool runs as a build step. The
generated DEX are then copied over to the device where they are loaded and run
the on-device DexBuilderTest.

Bug: 111895153

Change-Id: I06f5edd0e3e2f4e9ec2d14a0db7d22b75b424119

1 files changed, 85 insertions, 0 deletions

diff --git a/startop/view_compiler/dex_testcase_generator.cc b/startop/view_compiler/dex_testcase_generator.cc
new file mode 100644
index 000000000000..898817b4768c
--- /dev/null
+++ b/startop/view_compiler/dex_testcase_generator.cc
@@ -0,0 +1,85 @@
+/*
+ * Copyright (C) 2018 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "android-base/logging.h"
+#include "dex_builder.h"
+
+#include <fstream>
+#include <string>
+
+// Adding tests here requires changes in several other places. See README.md in
+// the view_compiler directory for more information.
+
+using namespace startop::dex;
+using namespace std;
+
+void GenerateTrivialDexFile(const string& outdir) {
+  DexBuilder dex_file;
+
+  ClassBuilder cbuilder{dex_file.MakeClass("android.startop.test.testcases.Trivial")};
+  cbuilder.set_source_file("dex_testcase_generator.cc#GenerateTrivialDexFile");
+
+  slicer::MemView image{dex_file.CreateImage()};
+  std::ofstream out_file(outdir + "/trivial.dex");
+  out_file.write(image.ptr<const char>(), image.size());
+}
+
+// Generates test cases that test around 1 instruction.
+void GenerateSimpleTestCases(const string& outdir) {
+  DexBuilder dex_file;
+
+  ClassBuilder cbuilder{dex_file.MakeClass("android.startop.test.testcases.SimpleTests")};
+  cbuilder.set_source_file("dex_testcase_generator.cc#GenerateSimpleTestCases");
+
+  // int return5() { return 5; }
+  auto return5{cbuilder.CreateMethod("return5", Prototype{TypeDescriptor::Int()})};
+  Value r{return5.MakeRegister()};
+  return5.BuildConst4(r, 5);
+  return5.BuildReturn(r);
+  return5.Encode();
+
+  // // int returnParam(int x) { return x; }
+  auto returnParam{cbuilder.CreateMethod("returnParam",
+                                         Prototype{TypeDescriptor::Int(), TypeDescriptor::Int()})};
+  returnParam.BuildReturn(Value::Parameter(0));
+  returnParam.Encode();
+
+  // int returnStringLength(String x) { return x.length(); }
+  auto string_type{TypeDescriptor::FromClassname("java.lang.String")};
+  MethodDeclData string_length{
+      dex_file.GetOrDeclareMethod(string_type, "length", Prototype{TypeDescriptor::Int()})};
+
+  auto returnStringLength{
+      cbuilder.CreateMethod("returnStringLength", Prototype{TypeDescriptor::Int(), string_type})};
+  Value result = returnStringLength.MakeRegister();
+  returnStringLength.AddInstruction(
+      Instruction::InvokeVirtual(string_length.id, result, Value::Parameter(0)));
+  returnStringLength.BuildReturn(result);
+  returnStringLength.Encode();
+
+  slicer::MemView image{dex_file.CreateImage()};
+  std::ofstream out_file(outdir + "/simple.dex");
+  out_file.write(image.ptr<const char>(), image.size());
+}
+
+int main(int argc, char** argv) {
+  CHECK_EQ(argc, 2);
+
+  string outdir = argv[1];
+
+  GenerateTrivialDexFile(outdir);
+  GenerateSimpleTestCases(outdir);
+}