[Lldb-commits] [lldb] [lldb][AIX] Added base files for NativeProcess Support for AIX (PR #118160)

[David Spickett via lldb-commits]

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@@ -0,0 +1,119 @@
+//===-- NativeProcessAIX.h ---------------------------------- -*- C++ -*-===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LIBLLDB_NATIVEPROCESSAIX_H_
+#define LIBLLDB_NATIVEPROCESSAIX_H_
+
+#include "Plugins/Process/Utility/NativeProcessSoftwareSingleStep.h"
+#include "lldb/Host/Debug.h"
+#include "lldb/Host/common/NativeProcessProtocol.h"
+#include "lldb/Target/MemoryRegionInfo.h"
+#include "lldb/Utility/ArchSpec.h"
+#include "lldb/Utility/FileSpec.h"
+#include "lldb/lldb-types.h"
+#include "llvm/ADT/SmallPtrSet.h"
+#include <csignal>
+#include <unordered_set>
+
+namespace lldb_private {
+
+namespace process_aix {
+/// \class NativeProcessAIX
+/// Manages communication with the inferior (debugee) process.
+///
+/// Upon construction, this class prepares and launches an inferior process
+/// for debugging.
+///
+/// Changes in the inferior process state are broadcasted.
+class NativeProcessAIX : public NativeProcessProtocol {
+public:
+  class Manager : public NativeProcessProtocol::Manager {
+  public:
+    Manager(MainLoop &mainloop);
+
+    llvm::Expected<std::unique_ptr<NativeProcessProtocol>>
+    Launch(ProcessLaunchInfo &launch_info,
+           NativeDelegate &native_delegate) override;
+
+    llvm::Expected<std::unique_ptr<NativeProcessProtocol>>
+    Attach(lldb::pid_t pid, NativeDelegate &native_delegate) override;
+
+    Extension GetSupportedExtensions() const override;
+
+    void AddProcess(NativeProcessAIX &process) { m_processes.insert(&process); }
+
+    void RemoveProcess(NativeProcessAIX &process) {
+      m_processes.erase(&process);
+    }
+
+    // Collect an event for the given tid, waiting for it if necessary.
+    void CollectThread(::pid_t tid);
+
+  private:
+    MainLoop::SignalHandleUP m_sigchld_handle;
+
+    llvm::SmallPtrSet<NativeProcessAIX *, 2> m_processes;
----------------
DavidSpickett wrote:

It's because SmallPtrSet is small as in "small string optimisation". So for 0, 1, or 2 pointers it'll be on the stack but anything more it moves to the heap.

We're always debugging at least 1 process, maybe you need 2 for certain common things programs do?

Anyway, it's arbitrary so no need to document anything here.

https://github.com/llvm/llvm-project/pull/118160