[Lldb-commits] [lldb] [lldb] Cache register types by object UID and register size (PR #215874)

[David Spickett via lldb-commits]

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@@ -0,0 +1,161 @@
+//===-- RegisterTypeBuilderClangTest.cpp ----------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "Plugins/RegisterTypeBuilder/RegisterTypeBuilderClang.h"
+#include "Plugins/Platform/Linux/PlatformLinux.h"
+#include "Plugins/TypeSystem/Clang/TypeSystemClang.h"
+#include "TestingSupport/SubsystemRAII.h"
+#include "TestingSupport/TestUtilities.h"
+#include "lldb/Core/Debugger.h"
+#include "lldb/Host/FileSystem.h"
+#include "lldb/Host/HostInfo.h"
+#include "lldb/Utility/ArchSpec.h"
+#include "lldb/Utility/RegisterInfo.h"
+#include "lldb/Utility/RegisterTypeFlags.h"
+#include "gtest/gtest.h"
+
+#include <mutex>
+#include <optional>
+
+using namespace lldb;
+using namespace lldb_private;
+
+namespace {
+
+class RegisterTypeBuilderClangTest : public testing::Test {
+public:
+  SubsystemRAII<FileSystem, HostInfo, TypeSystemClang,
+                platform_linux::PlatformLinux>
+      subsystems;
+
+protected:
+  void SetUp() override {
+    std::call_once(TestUtilities::g_debugger_initialize_flag,
+                   []() { Debugger::Initialize(nullptr); });
+    ArchSpec host_arch("x86_64-pc-linux");
+    Platform::SetHostPlatform(
+        platform_linux::PlatformLinux::CreateInstance(true, &host_arch));
+    m_debugger_sp = Debugger::CreateInstance();
+  }
+
+  static RegisterInfo MakeRegisterInfo(const RegisterType &type,
+                                       uint32_t byte_size) {
+    RegisterInfo info{};
+    info.name = "test";
+    info.byte_size = byte_size;
+    info.register_type = &type;
+    return info;
+  }
+
+  DebuggerSP m_debugger_sp;
+};
+
+TEST_F(RegisterTypeBuilderClangTest, ReusesCachedType) {
+  Target &target = m_debugger_sp->GetDummyTarget();
+  RegisterTypeFlags flags("flags", 4,
+                          {RegisterTypeFlags::Field("field", 0, 31)});
+  RegisterInfo info = MakeRegisterInfo(flags, 4);
+  RegisterTypeBuilderClang builder(target);
+
+  CompilerType first = builder.GetRegisterType(info);
+  CompilerType second = builder.GetRegisterType(info);
----------------
DavidSpickett wrote:

Is comparing CompilerType enough to prove that we are reusing the type? I looked a bit into it but am not sure what the thing underlying the CompilerType is.

Of course you can prove this another way, if you disable caching, this test should fail. Does it?

https://github.com/llvm/llvm-project/pull/215874