[Lldb-commits] [lldb] [llvm] [lldb][Process/FreeBSDKernel] Add riscv64 support (PR #180670)
Minsoo Choo via lldb-commits
lldb-commits at lists.llvm.org
Tue Feb 10 09:55:40 PST 2026
https://github.com/mchoo7 updated https://github.com/llvm/llvm-project/pull/180670
>From c294e465fc028e551e099595b3c7b89bed2e27ba Mon Sep 17 00:00:00 2001
From: Minsoo Choo <minsoochoo0122 at proton.me>
Date: Fri, 6 Feb 2026 10:02:48 -0500
Subject: [PATCH 1/2] [lldb][Process/FreeBSDKernel] Add riscv64 support
Signed-off-by: Minsoo Choo <minsoochoo0122 at proton.me>
---
lldb/docs/index.rst | 2 +-
.../Process/FreeBSDKernel/CMakeLists.txt | 1 +
.../RegisterContextFreeBSDKernel_riscv64.cpp | 110 ++++++++++++++++++
.../RegisterContextFreeBSDKernel_riscv64.h | 49 ++++++++
.../FreeBSDKernel/ThreadFreeBSDKernel.cpp | 8 ++
llvm/docs/ReleaseNotes.md | 1 +
6 files changed, 170 insertions(+), 1 deletion(-)
create mode 100644 lldb/source/Plugins/Process/FreeBSDKernel/RegisterContextFreeBSDKernel_riscv64.cpp
create mode 100644 lldb/source/Plugins/Process/FreeBSDKernel/RegisterContextFreeBSDKernel_riscv64.h
diff --git a/lldb/docs/index.rst b/lldb/docs/index.rst
index 10683c7593b01..d605d2649d94f 100644
--- a/lldb/docs/index.rst
+++ b/lldb/docs/index.rst
@@ -74,7 +74,7 @@ are welcome:
* iOS, tvOS, and watchOS device debugging on ARM and AArch64
* Linux user-space debugging for i386, x86_64, ARM, AArch64, PPC64le, s390x
* FreeBSD user-space debugging for i386, x86_64, ARM, AArch64, PPC
-* FreeBSD kernel debugging for i386, x86_64, AArch64
+* FreeBSD kernel debugging for i386, x86_64, AArch64, RISCV64
* NetBSD user-space debugging for i386 and x86_64
* Windows user-space debugging for i386, x86_64, ARM and AArch64 (*)
diff --git a/lldb/source/Plugins/Process/FreeBSDKernel/CMakeLists.txt b/lldb/source/Plugins/Process/FreeBSDKernel/CMakeLists.txt
index c35b4def24e25..d8a42c599a77e 100644
--- a/lldb/source/Plugins/Process/FreeBSDKernel/CMakeLists.txt
+++ b/lldb/source/Plugins/Process/FreeBSDKernel/CMakeLists.txt
@@ -15,6 +15,7 @@ add_lldb_library(lldbPluginProcessFreeBSDKernel PLUGIN
ProcessFreeBSDKernel.cpp
RegisterContextFreeBSDKernel_arm64.cpp
RegisterContextFreeBSDKernel_i386.cpp
+ RegisterContextFreeBSDKernel_riscv64.cpp
RegisterContextFreeBSDKernel_x86_64.cpp
ThreadFreeBSDKernel.cpp
diff --git a/lldb/source/Plugins/Process/FreeBSDKernel/RegisterContextFreeBSDKernel_riscv64.cpp b/lldb/source/Plugins/Process/FreeBSDKernel/RegisterContextFreeBSDKernel_riscv64.cpp
new file mode 100644
index 0000000000000..d93f3f3b0e807
--- /dev/null
+++ b/lldb/source/Plugins/Process/FreeBSDKernel/RegisterContextFreeBSDKernel_riscv64.cpp
@@ -0,0 +1,110 @@
+//===----------------------------------------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+///
+/// \file
+/// This file contains the definition of the
+/// RegisterContextFreeBSDKernel_riscv64 class, which is used for reading
+/// registers from PCB on ppc64le kernel dump.
+///
+//===----------------------------------------------------------------------===//
+
+#include "RegisterContextFreeBSDKernel_riscv64.h"
+
+#include "lldb/Target/Process.h"
+#include "lldb/Target/Thread.h"
+#include "lldb/Utility/RegisterValue.h"
+#include "llvm/Support/Endian.h"
+
+using namespace lldb;
+using namespace lldb_private;
+
+RegisterContextFreeBSDKernel_riscv64::RegisterContextFreeBSDKernel_riscv64(
+ Thread &thread, std::unique_ptr<RegisterInfoPOSIX_riscv64> register_info_up,
+ lldb::addr_t pcb_addr)
+ : RegisterContextPOSIX_riscv64(thread, std::move(register_info_up)),
+ m_pcb_addr(pcb_addr) {}
+
+bool RegisterContextFreeBSDKernel_riscv64::ReadGPR() { return true; }
+
+bool RegisterContextFreeBSDKernel_riscv64::ReadFPR() { return true; }
+
+bool RegisterContextFreeBSDKernel_riscv64::WriteGPR() {
+ assert(0);
+ return false;
+}
+
+bool RegisterContextFreeBSDKernel_riscv64::WriteFPR() {
+ assert(0);
+ return false;
+}
+
+bool RegisterContextFreeBSDKernel_riscv64::ReadRegister(
+ const RegisterInfo *reg_info, RegisterValue &value) {
+ if (m_pcb_addr == LLDB_INVALID_ADDRESS)
+ return false;
+
+ // https://cgit.freebsd.org/src/tree/sys/riscv/include/pcb.h
+ struct {
+ llvm::support::ulittle64_t ra;
+ llvm::support::ulittle64_t sp;
+ llvm::support::ulittle64_t gp;
+ llvm::support::ulittle64_t tp;
+ llvm::support::ulittle64_t s[12];
+ } pcb;
+
+ Status error;
+ size_t rd =
+ m_thread.GetProcess()->ReadMemory(m_pcb_addr, &pcb, sizeof(pcb), error);
+ if (rd != sizeof(pcb))
+ return false;
+
+ uint32_t reg = reg_info->kinds[lldb::eRegisterKindLLDB];
+ switch (reg) {
+ case gpr_pc_riscv:
+ // Supply the RA as PC as well to simulate the PC as if the thread had just
+ // returned.
+ case gpr_ra_riscv:
+ value = pcb.ra;
+ break;
+ case gpr_sp_riscv:
+ value = pcb.sp;
+ break;
+ case gpr_gp_riscv:
+ value = pcb.gp;
+ break;
+ case gpr_tp_riscv:
+ value = pcb.tp;
+ break;
+ case gpr_fp_riscv:
+ value = pcb.s[0];
+ break;
+ case gpr_s1_riscv:
+ value = pcb.s[1];
+ break;
+ case gpr_s2_riscv:
+ case gpr_s3_riscv:
+ case gpr_s4_riscv:
+ case gpr_s5_riscv:
+ case gpr_s6_riscv:
+ case gpr_s7_riscv:
+ case gpr_s8_riscv:
+ case gpr_s9_riscv:
+ case gpr_s10_riscv:
+ case gpr_s11_riscv:
+ value = pcb.s[reg - gpr_s2_riscv];
+ break;
+ default:
+ return false;
+ }
+ return true;
+}
+
+bool RegisterContextFreeBSDKernel_riscv64::WriteRegister(
+ const RegisterInfo *reg_info, const RegisterValue &value) {
+ return false;
+}
diff --git a/lldb/source/Plugins/Process/FreeBSDKernel/RegisterContextFreeBSDKernel_riscv64.h b/lldb/source/Plugins/Process/FreeBSDKernel/RegisterContextFreeBSDKernel_riscv64.h
new file mode 100644
index 0000000000000..789d203d8c158
--- /dev/null
+++ b/lldb/source/Plugins/Process/FreeBSDKernel/RegisterContextFreeBSDKernel_riscv64.h
@@ -0,0 +1,49 @@
+//===----------------------------------------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+///
+/// \file
+/// This file contains the declaration of the
+/// RegisterContextFreeBSDKernel_riscv64 class, which is used for reading
+/// registers from PCB on ppc64le kernel dump.
+///
+//===----------------------------------------------------------------------===//
+
+#ifndef LLDB_SOURCE_PLUGINS_PROCESS_FREEBSDKERNEL_REGISTERCONTEXTFREEBSDKERNEL_RISCV64_H
+#define LLDB_SOURCE_PLUGINS_PROCESS_FREEBSDKERNEL_REGISTERCONTEXTFREEBSDKERNEL_RISCV64_H
+
+#include "Plugins/Process/Utility/RegisterContextPOSIX_riscv64.h"
+#include "Plugins/Process/elf-core/RegisterUtilities.h"
+
+class RegisterContextFreeBSDKernel_riscv64
+ : public RegisterContextPOSIX_riscv64 {
+public:
+ RegisterContextFreeBSDKernel_riscv64(
+ lldb_private::Thread &thread,
+ std::unique_ptr<RegisterInfoPOSIX_riscv64> register_info_up,
+ lldb::addr_t pcb_addr);
+
+ bool ReadRegister(const lldb_private::RegisterInfo *reg_info,
+ lldb_private::RegisterValue &value) override;
+
+ bool WriteRegister(const lldb_private::RegisterInfo *reg_info,
+ const lldb_private::RegisterValue &value) override;
+
+protected:
+ bool ReadGPR() override;
+
+ bool ReadFPR() override;
+
+ bool WriteGPR() override;
+
+ bool WriteFPR() override;
+
+private:
+ lldb::addr_t m_pcb_addr;
+};
+
+#endif // LLDB_SOURCE_PLUGINS_PROCESS_FREEBSDKERNEL_REGISTERCONTEXTFREEBSDKERNEL_RISCV64_H
diff --git a/lldb/source/Plugins/Process/FreeBSDKernel/ThreadFreeBSDKernel.cpp b/lldb/source/Plugins/Process/FreeBSDKernel/ThreadFreeBSDKernel.cpp
index dd1ed52719749..28de9bed05519 100644
--- a/lldb/source/Plugins/Process/FreeBSDKernel/ThreadFreeBSDKernel.cpp
+++ b/lldb/source/Plugins/Process/FreeBSDKernel/ThreadFreeBSDKernel.cpp
@@ -15,9 +15,11 @@
#include "Plugins/Process/Utility/RegisterContextFreeBSD_i386.h"
#include "Plugins/Process/Utility/RegisterContextFreeBSD_x86_64.h"
#include "Plugins/Process/Utility/RegisterInfoPOSIX_arm64.h"
+#include "Plugins/Process/Utility/RegisterInfoPOSIX_riscv64.h"
#include "ProcessFreeBSDKernel.h"
#include "RegisterContextFreeBSDKernel_arm64.h"
#include "RegisterContextFreeBSDKernel_i386.h"
+#include "RegisterContextFreeBSDKernel_riscv64.h"
#include "RegisterContextFreeBSDKernel_x86_64.h"
using namespace lldb;
@@ -62,6 +64,12 @@ ThreadFreeBSDKernel::CreateRegisterContextForFrame(StackFrame *frame) {
*this, std::make_unique<RegisterInfoPOSIX_arm64>(arch, 0),
m_pcb_addr);
break;
+ case llvm::Triple::riscv64:
+ m_thread_reg_ctx_sp =
+ std::make_shared<RegisterContextFreeBSDKernel_riscv64>(
+ *this, std::make_unique<RegisterInfoPOSIX_riscv64>(arch, 0),
+ m_pcb_addr);
+ break;
case llvm::Triple::x86:
m_thread_reg_ctx_sp = std::make_shared<RegisterContextFreeBSDKernel_i386>(
*this, new RegisterContextFreeBSD_i386(arch), m_pcb_addr);
diff --git a/llvm/docs/ReleaseNotes.md b/llvm/docs/ReleaseNotes.md
index 30e74acf973ed..d37af4f25b503 100644
--- a/llvm/docs/ReleaseNotes.md
+++ b/llvm/docs/ReleaseNotes.md
@@ -182,6 +182,7 @@ Changes to LLDB
* Support for FreeBSD on MIPS64 has been removed.
* The minimum assumed version of FreeBSD is now 14. The effect of which is that watchpoints are
assumed to be supported.
+* Kernel debugging support for RISCV64 on FreeBSD has been added.
Changes to BOLT
---------------
>From e6b814d985998c176f8d7bd0bcfbdece2ce57fe6 Mon Sep 17 00:00:00 2001
From: Minsoo Choo <minsoochoo0122 at proton.me>
Date: Tue, 10 Feb 2026 12:55:10 -0500
Subject: [PATCH 2/2] fixup! [lldb][Process/FreeBSDKernel] Add riscv64 support
Signed-off-by: Minsoo Choo <minsoochoo0122 at proton.me>
---
.../FreeBSDKernel/RegisterContextFreeBSDKernel_riscv64.cpp | 2 +-
.../FreeBSDKernel/RegisterContextFreeBSDKernel_riscv64.h | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/lldb/source/Plugins/Process/FreeBSDKernel/RegisterContextFreeBSDKernel_riscv64.cpp b/lldb/source/Plugins/Process/FreeBSDKernel/RegisterContextFreeBSDKernel_riscv64.cpp
index d93f3f3b0e807..5d6cd56860066 100644
--- a/lldb/source/Plugins/Process/FreeBSDKernel/RegisterContextFreeBSDKernel_riscv64.cpp
+++ b/lldb/source/Plugins/Process/FreeBSDKernel/RegisterContextFreeBSDKernel_riscv64.cpp
@@ -9,7 +9,7 @@
/// \file
/// This file contains the definition of the
/// RegisterContextFreeBSDKernel_riscv64 class, which is used for reading
-/// registers from PCB on ppc64le kernel dump.
+/// registers from PCB on riscv64 kernel dump.
///
//===----------------------------------------------------------------------===//
diff --git a/lldb/source/Plugins/Process/FreeBSDKernel/RegisterContextFreeBSDKernel_riscv64.h b/lldb/source/Plugins/Process/FreeBSDKernel/RegisterContextFreeBSDKernel_riscv64.h
index 789d203d8c158..277fb5bfed96f 100644
--- a/lldb/source/Plugins/Process/FreeBSDKernel/RegisterContextFreeBSDKernel_riscv64.h
+++ b/lldb/source/Plugins/Process/FreeBSDKernel/RegisterContextFreeBSDKernel_riscv64.h
@@ -9,7 +9,7 @@
/// \file
/// This file contains the declaration of the
/// RegisterContextFreeBSDKernel_riscv64 class, which is used for reading
-/// registers from PCB on ppc64le kernel dump.
+/// registers from PCB on riscv64 kernel dump.
///
//===----------------------------------------------------------------------===//
More information about the lldb-commits
mailing list