Fallback to quick in case of soft verification errors

Add a regression test: using uninitialized values triggers a soft
verification error and optimizing should not crash.

Thanks to Stephen Kyle (stephenckyle@googlemail.com) for the bug report.

Bug: 19988704
Change-Id: I67174538eed853baff735694b3ae8eb34afe2a39
diff --git a/compiler/driver/compiler_driver.cc b/compiler/driver/compiler_driver.cc
index ef47377..641d174 100644
--- a/compiler/driver/compiler_driver.cc
+++ b/compiler/driver/compiler_driver.cc
@@ -2344,6 +2344,31 @@
   return it->second;
 }
 
+bool CompilerDriver::IsMethodVerifiedWithoutFailures(uint32_t method_idx,
+                                                     uint16_t class_def_idx,
+                                                     const DexFile& dex_file) const {
+  const VerifiedMethod* verified_method = GetVerifiedMethod(&dex_file, method_idx);
+  if (verified_method != nullptr) {
+    return !verified_method->HasVerificationFailures();
+  }
+
+  // If we can't find verification metadata, check if this is a system class (we trust that system
+  // classes have their methods verified). If it's not, be conservative and assume the method
+  // has not been verified successfully.
+
+  // TODO: When compiling the boot image it should be safe to assume that everything is verified,
+  // even if methods are not found in the verification cache.
+  const char* descriptor = dex_file.GetClassDescriptor(dex_file.GetClassDef(class_def_idx));
+  ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
+  Thread* self = Thread::Current();
+  ScopedObjectAccess soa(self);
+  bool is_system_class = class_linker->FindSystemClass(self, descriptor) != nullptr;
+  if (!is_system_class) {
+    self->ClearException();
+  }
+  return is_system_class;
+}
+
 size_t CompilerDriver::GetNonRelativeLinkerPatchCount() const {
   MutexLock mu(Thread::Current(), compiled_methods_lock_);
   return non_relative_linker_patch_count_;