[Lldb-commits] [lldb] [lldb][AIX] Added RegisterInfo file for PPC64 (PR #165367)

[Hemang Gadhavi via lldb-commits]

https://github.com/HemangGadhavi created https://github.com/llvm/llvm-project/pull/165367

This PR is in reference to porting LLDB on AIX.
Link to discussions on llvm discourse and github:

1. https://discourse.llvm.org/t/port-lldb-to-ibm-aix/80640
2. https://github.com/llvm/llvm-project/issues/101657
The complete changes for porting are present in this draft PR:
https://github.com/llvm/llvm-project/pull/102601

- Added register information file for PPC64 big-endian architecture (used by AIX)
@DavidSpickett @labath @DhruvSrivastavaX 

>From a9c6cef1e9cb0f7a9c60c623f2d0b74699b66f06 Mon Sep 17 00:00:00 2001
From: HemangGadhavi <hemang.gadhavi at ibm.com>
Date: Tue, 28 Oct 2025 05:20:52 -0500
Subject: [PATCH] [lldb][AIX] Added RegisterInfo file for PPC64

---
 .../Plugins/Process/Utility/CMakeLists.txt    |  1 +
 .../Utility/RegisterInfoPOSIX_ppc64.cpp       | 61 +++++++++++++++++++
 .../Process/Utility/RegisterInfoPOSIX_ppc64.h | 31 ++++++++++
 3 files changed, 93 insertions(+)
 create mode 100644 lldb/source/Plugins/Process/Utility/RegisterInfoPOSIX_ppc64.cpp
 create mode 100644 lldb/source/Plugins/Process/Utility/RegisterInfoPOSIX_ppc64.h

diff --git a/lldb/source/Plugins/Process/Utility/CMakeLists.txt b/lldb/source/Plugins/Process/Utility/CMakeLists.txt
index b1e326ec064e4..997fdbda05839 100644
--- a/lldb/source/Plugins/Process/Utility/CMakeLists.txt
+++ b/lldb/source/Plugins/Process/Utility/CMakeLists.txt
@@ -60,6 +60,7 @@ add_lldb_library(lldbPluginProcessUtility
   RegisterInfoPOSIX_arm64.cpp
   RegisterInfoPOSIX_loongarch64.cpp
   RegisterInfoPOSIX_ppc64le.cpp
+  RegisterInfoPOSIX_ppc64.cpp
   RegisterInfoPOSIX_riscv32.cpp
   RegisterInfoPOSIX_riscv64.cpp
   StopInfoMachException.cpp
diff --git a/lldb/source/Plugins/Process/Utility/RegisterInfoPOSIX_ppc64.cpp b/lldb/source/Plugins/Process/Utility/RegisterInfoPOSIX_ppc64.cpp
new file mode 100644
index 0000000000000..1550f00bea28e
--- /dev/null
+++ b/lldb/source/Plugins/Process/Utility/RegisterInfoPOSIX_ppc64.cpp
@@ -0,0 +1,61 @@
+//===-- RegisterInfoPOSIX_ppc64.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 <cassert>
+#include <cstddef>
+#include <vector>
+
+#include "lldb/lldb-defines.h"
+#include "llvm/Support/Compiler.h"
+
+#include "RegisterInfoPOSIX_ppc64.h"
+
+// Include RegisterInfoPOSIX_ppc64 to declare our g_register_infos_ppc64
+#define DECLARE_REGISTER_INFOS_PPC64_STRUCT
+#include "RegisterInfos_ppc64.h"
+#undef DECLARE_REGISTER_INFOS_PPC64_STRUCT
+
+static const lldb_private::RegisterInfo *
+GetRegisterInfoPtr(const lldb_private::ArchSpec &target_arch) {
+  switch (target_arch.GetMachine()) {
+  case llvm::Triple::ppc64:
+    return g_register_infos_ppc64;
+  default:
+    assert(false && "Unhandled target architecture.");
+    return nullptr;
+  }
+}
+
+static uint32_t
+GetRegisterInfoCount(const lldb_private::ArchSpec &target_arch) {
+  switch (target_arch.GetMachine()) {
+  case llvm::Triple::ppc64:
+    return static_cast<uint32_t>(sizeof(g_register_infos_ppc64) /
+                                 sizeof(g_register_infos_ppc64[0]));
+  default:
+    assert(false && "Unhandled target architecture.");
+    return 0;
+  }
+}
+
+RegisterInfoPOSIX_ppc64::RegisterInfoPOSIX_ppc64(
+    const lldb_private::ArchSpec &target_arch)
+    : lldb_private::RegisterInfoInterface(target_arch),
+      m_register_info_p(GetRegisterInfoPtr(target_arch)),
+      m_register_info_count(GetRegisterInfoCount(target_arch)) {}
+
+size_t RegisterInfoPOSIX_ppc64::GetGPRSize() const { return sizeof(GPR_PPC64); }
+
+const lldb_private::RegisterInfo *
+RegisterInfoPOSIX_ppc64::GetRegisterInfo() const {
+  return m_register_info_p;
+}
+
+uint32_t RegisterInfoPOSIX_ppc64::GetRegisterCount() const {
+  return m_register_info_count;
+}
diff --git a/lldb/source/Plugins/Process/Utility/RegisterInfoPOSIX_ppc64.h b/lldb/source/Plugins/Process/Utility/RegisterInfoPOSIX_ppc64.h
new file mode 100644
index 0000000000000..4805883e5b848
--- /dev/null
+++ b/lldb/source/Plugins/Process/Utility/RegisterInfoPOSIX_ppc64.h
@@ -0,0 +1,31 @@
+//===-- RegisterInfoPOSIX_ppc64.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 LLDB_SOURCE_PLUGINS_PROCESS_UTILITY_REGISTERINFOPOSIX_PPC64_H
+#define LLDB_SOURCE_PLUGINS_PROCESS_UTILITY_REGISTERINFOPOSIX_PPC64_H
+
+#include "RegisterInfoInterface.h"
+#include "lldb/Target/RegisterContext.h"
+#include "lldb/lldb-private.h"
+
+class RegisterInfoPOSIX_ppc64 : public lldb_private::RegisterInfoInterface {
+public:
+  RegisterInfoPOSIX_ppc64(const lldb_private::ArchSpec &target_arch);
+
+  size_t GetGPRSize() const override;
+
+  const lldb_private::RegisterInfo *GetRegisterInfo() const override;
+
+  uint32_t GetRegisterCount() const override;
+
+private:
+  const lldb_private::RegisterInfo *m_register_info_p;
+  uint32_t m_register_info_count;
+};
+
+#endif // #ifndef LLDB_SOURCE_PLUGINS_PROCESS_UTILITY_REGISTERINFOPOSIX_PPC64_H