diff --git a/lldb/include/lldb/Utility/ArchSpec.h b/lldb/include/lldb/Utility/ArchSpec.h
--- a/lldb/include/lldb/Utility/ArchSpec.h
+++ b/lldb/include/lldb/Utility/ArchSpec.h
@@ -180,6 +180,9 @@
     eCore_hexagon_hexagonv4,
     eCore_hexagon_hexagonv5,
 
+    eCore_riscv32,
+    eCore_riscv64,
+
     eCore_uknownMach32,
     eCore_uknownMach64,
 
diff --git a/lldb/source/API/SystemInitializerFull.cpp b/lldb/source/API/SystemInitializerFull.cpp
--- a/lldb/source/API/SystemInitializerFull.cpp
+++ b/lldb/source/API/SystemInitializerFull.cpp
@@ -32,6 +32,7 @@
 #include "Plugins/ABI/SysV-mips64/ABISysV_mips64.h"
 #include "Plugins/ABI/SysV-ppc/ABISysV_ppc.h"
 #include "Plugins/ABI/SysV-ppc64/ABISysV_ppc64.h"
+#include "Plugins/ABI/SysV-riscv/ABISysV_riscv.h"
 #include "Plugins/ABI/SysV-s390x/ABISysV_s390x.h"
 #include "Plugins/ABI/SysV-x86_64/ABISysV_x86_64.h"
 #include "Plugins/Architecture/Arm/ArchitectureArm.h"
@@ -185,6 +186,7 @@
   ABISysV_ppc64::Initialize();
   ABISysV_mips::Initialize();
   ABISysV_mips64::Initialize();
+  ABISysV_riscv::Initialize();
   ABISysV_s390x::Initialize();
 
   ArchitectureArm::Initialize();
diff --git a/lldb/source/Plugins/ABI/CMakeLists.txt b/lldb/source/Plugins/ABI/CMakeLists.txt
--- a/lldb/source/Plugins/ABI/CMakeLists.txt
+++ b/lldb/source/Plugins/ABI/CMakeLists.txt
@@ -8,6 +8,7 @@
 add_subdirectory(SysV-s390x)
 add_subdirectory(SysV-i386)
 add_subdirectory(SysV-x86_64)
+add_subdirectory(SysV-riscv)
 add_subdirectory(MacOSX-i386)
 add_subdirectory(MacOSX-arm)
 add_subdirectory(MacOSX-arm64)
diff --git a/lldb/source/Plugins/ABI/SysV-riscv/ABISysV_riscv.h b/lldb/source/Plugins/ABI/SysV-riscv/ABISysV_riscv.h
new file mode 100644
--- /dev/null
+++ b/lldb/source/Plugins/ABI/SysV-riscv/ABISysV_riscv.h
@@ -0,0 +1,112 @@
+//===-- ABISysV_riscv.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_ABISysV_riscv_h_
+#define liblldb_ABISysV_riscv_h_
+
+#include "lldb/Target/ABI.h"
+#include "lldb/lldb-private.h"
+
+class ABISysV_riscv : public lldb_private::ABI {
+  bool isRV64;
+
+public:
+  size_t GetRedZoneSize() const override { return 0; }
+
+  bool PrepareTrivialCall(lldb_private::Thread &thread, lldb::addr_t sp,
+                          lldb::addr_t functionAddress,
+                          lldb::addr_t returnAddress,
+                          llvm::ArrayRef<lldb::addr_t> args) const override {
+    // TODO: Implement
+    return false;
+  }
+
+  bool GetArgumentValues(lldb_private::Thread &thread,
+                         lldb_private::ValueList &values) const override {
+    // TODO: Implement
+    return false;
+  }
+
+  lldb_private::Status
+  SetReturnValueObject(lldb::StackFrameSP &frame_sp,
+                       lldb::ValueObjectSP &new_value) override {
+    // TODO: Implement
+    lldb_private::Status error;
+    error.SetErrorString("Not yet implemented");
+    return error;
+  }
+
+  lldb::ValueObjectSP
+  GetReturnValueObjectImpl(lldb_private::Thread &thread,
+                           lldb_private::CompilerType &type) const override {
+    // TODO: Implement
+    lldb::ValueObjectSP return_valobj;
+    return return_valobj;
+  }
+
+  bool CreateFunctionEntryUnwindPlan(
+      lldb_private::UnwindPlan &unwind_plan) override {
+    // TODO: Implement disassembly-based unwinding
+    unwind_plan.Clear();
+    return false;
+  }
+
+  bool CreateDefaultUnwindPlan(lldb_private::UnwindPlan &unwind_plan) override {
+    // TODO: Implement disassembly-based unwinding
+    unwind_plan.Clear();
+    return true;
+  }
+
+  bool RegisterIsVolatile(const lldb_private::RegisterInfo *reg_info) override {
+    // TODO: Implement
+    return false;
+  }
+
+  bool CallFrameAddressIsValid(lldb::addr_t cfa) override {
+    // Assume any address except zero is valid
+    if (cfa == 0)
+      return false;
+    return true;
+  }
+
+  bool CodeAddressIsValid(lldb::addr_t pc) override {
+    // Any address in the address space is valid
+    if (!isRV64)
+      return (pc <= UINT32_MAX);
+    return (pc <= UINT64_MAX);
+  }
+
+  const lldb_private::RegisterInfo *
+  GetRegisterInfoArray(uint32_t &count) override;
+
+  // Static Functions
+
+  static void Initialize();
+
+  static void Terminate();
+
+  static lldb::ABISP CreateInstance(lldb::ProcessSP process_sp,
+                                    const lldb_private::ArchSpec &arch);
+
+  // PluginInterface protocol
+
+  static lldb_private::ConstString GetPluginNameStatic();
+
+  lldb_private::ConstString GetPluginName() override;
+
+  uint32_t GetPluginVersion() override { return 1; }
+
+protected:
+private:
+  ABISysV_riscv(lldb::ProcessSP process_sp, bool _isRV64)
+      : lldb_private::ABI(process_sp), isRV64(_isRV64) {
+    // Call CreateInstance instead.
+  }
+};
+
+#endif // liblldb_ABISysV_riscv_h_
diff --git a/lldb/source/Plugins/ABI/SysV-riscv/ABISysV_riscv.cpp b/lldb/source/Plugins/ABI/SysV-riscv/ABISysV_riscv.cpp
new file mode 100644
--- /dev/null
+++ b/lldb/source/Plugins/ABI/SysV-riscv/ABISysV_riscv.cpp
@@ -0,0 +1,832 @@
+//===-- ABISysV_riscv.cpp ---------------------------------------*- 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
+//===----------------------------------------------------------------------===//
+
+#include "ABISysV_riscv.h"
+
+#include "llvm/ADT/STLExtras.h"
+#include "llvm/ADT/Triple.h"
+
+#include "lldb/Core/Module.h"
+#include "lldb/Core/PluginManager.h"
+#include "lldb/Core/Value.h"
+#include "lldb/Core/ValueObjectConstResult.h"
+#include "lldb/Core/ValueObjectMemory.h"
+#include "lldb/Core/ValueObjectRegister.h"
+#include "lldb/Symbol/UnwindPlan.h"
+#include "lldb/Target/Process.h"
+#include "lldb/Target/RegisterContext.h"
+#include "lldb/Target/StackFrame.h"
+#include "lldb/Target/Target.h"
+#include "lldb/Target/Thread.h"
+#include "lldb/Utility/ConstString.h"
+#include "lldb/Utility/DataExtractor.h"
+#include "lldb/Utility/Log.h"
+#include "lldb/Utility/RegisterValue.h"
+#include "lldb/Utility/Status.h"
+
+using namespace lldb;
+using namespace lldb_private;
+
+static RegisterInfo g_register_infos_rv32[] = {
+    {"x0",
+     "zero",
+     4,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {0, 0, LLDB_INVALID_REGNUM, 0, 0},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x1",
+     "ra",
+     4,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {1, 1, LLDB_REGNUM_GENERIC_RA, 1, 1},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x2",
+     "sp",
+     4,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {2, 2, LLDB_REGNUM_GENERIC_SP, 2, 2},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x3",
+     "gp",
+     4,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {3, 3, LLDB_INVALID_REGNUM, 3, 3},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x4",
+     "tp",
+     4,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {4, 4, LLDB_INVALID_REGNUM, 4, 4},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x5",
+     "t0",
+     4,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {5, 5, LLDB_INVALID_REGNUM, 5, 5},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x6",
+     "t1",
+     4,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {6, 6, LLDB_INVALID_REGNUM, 6, 6},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x7",
+     "t2",
+     4,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {7, 7, LLDB_INVALID_REGNUM, 7, 7},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x8",
+     "s0",
+     4,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {8, 8, LLDB_INVALID_REGNUM, 8, 8},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x9",
+     "s1",
+     4,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {9, 9, LLDB_INVALID_REGNUM, 9, 9},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x10",
+     "a0",
+     4,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {10, 10, LLDB_INVALID_REGNUM, 10, 10},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x11",
+     "a1",
+     4,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {11, 11, LLDB_INVALID_REGNUM, 11, 11},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x12",
+     "a2",
+     4,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {12, 12, LLDB_INVALID_REGNUM, 12, 12},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x13",
+     "a3",
+     4,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {13, 13, LLDB_INVALID_REGNUM, 13, 13},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x14",
+     "a4",
+     4,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {14, 14, LLDB_INVALID_REGNUM, 14, 14},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x15",
+     "a5",
+     4,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {15, 15, LLDB_INVALID_REGNUM, 15, 15},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x16",
+     "a6",
+     4,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {16, 16, LLDB_INVALID_REGNUM, 16, 16},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x17",
+     "a7",
+     4,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {17, 17, LLDB_INVALID_REGNUM, 17, 17},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x18",
+     "s2",
+     4,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {18, 18, LLDB_INVALID_REGNUM, 18, 18},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x19",
+     "s3",
+     4,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {19, 19, LLDB_INVALID_REGNUM, 19, 19},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x20",
+     "s4",
+     4,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {20, 20, LLDB_INVALID_REGNUM, 20, 20},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x21",
+     "s5",
+     4,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {21, 21, LLDB_INVALID_REGNUM, 21, 21},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x22",
+     "s6",
+     4,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {22, 22, LLDB_INVALID_REGNUM, 22, 22},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x23",
+     "s7",
+     4,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {23, 23, LLDB_INVALID_REGNUM, 23, 23},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x24",
+     "s8",
+     4,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {24, 24, LLDB_INVALID_REGNUM, 24, 24},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x25",
+     "s9",
+     4,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {25, 25, LLDB_INVALID_REGNUM, 25, 25},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x26",
+     "s10",
+     4,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {26, 26, LLDB_INVALID_REGNUM, 26, 26},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x27",
+     "s11",
+     4,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {27, 27, LLDB_INVALID_REGNUM, 27, 27},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x28",
+     "t3",
+     4,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {28, 28, LLDB_INVALID_REGNUM, 28, 28},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x29",
+     "t4",
+     4,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {29, 29, LLDB_INVALID_REGNUM, 29, 29},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x30",
+     "t5",
+     4,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {30, 30, LLDB_INVALID_REGNUM, 30, 30},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x31",
+     "t6",
+     4,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {31, 31, LLDB_INVALID_REGNUM, 31, 31},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"pc",
+     nullptr,
+     4,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM, LLDB_REGNUM_GENERIC_PC,
+      LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+};
+
+static RegisterInfo g_register_infos_rv64[] = {
+    {"x0",
+     "zero",
+     8,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {0, 0, LLDB_INVALID_REGNUM, 0, 0},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x1",
+     "ra",
+     8,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {1, 1, LLDB_REGNUM_GENERIC_RA, 1, 1},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x2",
+     "sp",
+     8,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {2, 2, LLDB_REGNUM_GENERIC_SP, 2, 2},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x3",
+     "gp",
+     8,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {3, 3, LLDB_INVALID_REGNUM, 3, 3},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x4",
+     "tp",
+     8,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {4, 4, LLDB_INVALID_REGNUM, 4, 4},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x5",
+     "t0",
+     8,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {5, 5, LLDB_INVALID_REGNUM, 5, 5},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x6",
+     "t1",
+     8,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {6, 6, LLDB_INVALID_REGNUM, 6, 6},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x7",
+     "t2",
+     8,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {7, 7, LLDB_INVALID_REGNUM, 7, 7},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x8",
+     "s0",
+     8,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {8, 8, LLDB_INVALID_REGNUM, 8, 8},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x9",
+     "s1",
+     8,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {9, 9, LLDB_INVALID_REGNUM, 9, 9},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x10",
+     "a0",
+     8,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {10, 10, LLDB_INVALID_REGNUM, 10, 10},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x11",
+     "a1",
+     8,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {11, 11, LLDB_INVALID_REGNUM, 11, 11},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x12",
+     "a2",
+     8,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {12, 12, LLDB_INVALID_REGNUM, 12, 12},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x13",
+     "a3",
+     8,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {13, 13, LLDB_INVALID_REGNUM, 13, 13},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x14",
+     "a4",
+     8,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {14, 14, LLDB_INVALID_REGNUM, 14, 14},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x15",
+     "a5",
+     8,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {15, 15, LLDB_INVALID_REGNUM, 15, 15},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x16",
+     "a6",
+     8,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {16, 16, LLDB_INVALID_REGNUM, 16, 16},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x17",
+     "a7",
+     8,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {17, 17, LLDB_INVALID_REGNUM, 17, 17},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x18",
+     "s2",
+     8,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {18, 18, LLDB_INVALID_REGNUM, 18, 18},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x19",
+     "s3",
+     8,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {19, 19, LLDB_INVALID_REGNUM, 19, 19},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x20",
+     "s4",
+     8,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {20, 20, LLDB_INVALID_REGNUM, 20, 20},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x21",
+     "s5",
+     8,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {21, 21, LLDB_INVALID_REGNUM, 21, 21},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x22",
+     "s6",
+     8,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {22, 22, LLDB_INVALID_REGNUM, 22, 22},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x23",
+     "s7",
+     8,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {23, 23, LLDB_INVALID_REGNUM, 23, 23},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x24",
+     "s8",
+     8,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {24, 24, LLDB_INVALID_REGNUM, 24, 24},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x25",
+     "s9",
+     8,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {25, 25, LLDB_INVALID_REGNUM, 25, 25},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x26",
+     "s10",
+     8,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {26, 26, LLDB_INVALID_REGNUM, 26, 26},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x27",
+     "s11",
+     8,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {27, 27, LLDB_INVALID_REGNUM, 27, 27},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x28",
+     "t3",
+     8,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {28, 28, LLDB_INVALID_REGNUM, 28, 28},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x29",
+     "t4",
+     8,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {29, 29, LLDB_INVALID_REGNUM, 29, 29},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x30",
+     "t5",
+     8,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {30, 30, LLDB_INVALID_REGNUM, 30, 30},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"x31",
+     "t6",
+     8,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {31, 31, LLDB_INVALID_REGNUM, 31, 31},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+    {"pc",
+     nullptr,
+     8,
+     0,
+     eEncodingUint,
+     eFormatHex,
+     {LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM, LLDB_REGNUM_GENERIC_PC,
+      LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM},
+     nullptr,
+     nullptr,
+     nullptr,
+     0},
+};
+
+static const uint32_t k_num_register_infos_rv32 =
+    llvm::array_lengthof(g_register_infos_rv32);
+static const uint32_t k_num_register_infos_rv64 =
+    llvm::array_lengthof(g_register_infos_rv64);
+static bool g_register_info_names_constified = false;
+
+static void ConstantifyTable(RegisterInfo *register_infos, uint32_t count) {
+  for (uint32_t i = 0; i < count; ++i) {
+    if (register_infos[i].name)
+      register_infos[i].name = ConstString(register_infos[i].name).GetCString();
+    if (register_infos[i].alt_name)
+      register_infos[i].alt_name =
+          ConstString(register_infos[i].alt_name).GetCString();
+  }
+}
+
+const lldb_private::RegisterInfo *
+ABISysV_riscv::GetRegisterInfoArray(uint32_t &count) {
+  // Make the C-string names and alt_names for the register infos into const
+  // C-string values by having the ConstString unique the names in the global
+  // constant C-string pool.
+  if (!g_register_info_names_constified) {
+    g_register_info_names_constified = true;
+    ConstantifyTable(g_register_infos_rv32, k_num_register_infos_rv32);
+    ConstantifyTable(g_register_infos_rv64, k_num_register_infos_rv64);
+  }
+
+  if (isRV64) {
+    count = k_num_register_infos_rv64;
+    return g_register_infos_rv64;
+  }
+  count = k_num_register_infos_rv32;
+  return g_register_infos_rv32;
+}
+
+ABISP
+ABISysV_riscv::CreateInstance(lldb::ProcessSP process_sp,
+                              const ArchSpec &arch) {
+  if (arch.GetTriple().getArch() == llvm::Triple::riscv32 ||
+      arch.GetTriple().getArch() == llvm::Triple::riscv64) {
+    return ABISP(new ABISysV_riscv(process_sp, arch.GetTriple().getArch() ==
+                                                   llvm::Triple::riscv64));
+  }
+  return ABISP();
+}
+
+void ABISysV_riscv::Initialize() {
+  PluginManager::RegisterPlugin(
+      GetPluginNameStatic(), "System V ABI for riscv targets", CreateInstance);
+}
+
+void ABISysV_riscv::Terminate() {
+  PluginManager::UnregisterPlugin(CreateInstance);
+}
+
+// PluginInterface protocol
+
+lldb_private::ConstString ABISysV_riscv::GetPluginNameStatic() {
+  static ConstString g_name("sysv-riscv");
+  return g_name;
+}
+
+lldb_private::ConstString ABISysV_riscv::GetPluginName() {
+  return GetPluginNameStatic();
+}
diff --git a/lldb/source/Plugins/ABI/SysV-riscv/CMakeLists.txt b/lldb/source/Plugins/ABI/SysV-riscv/CMakeLists.txt
new file mode 100644
--- /dev/null
+++ b/lldb/source/Plugins/ABI/SysV-riscv/CMakeLists.txt
@@ -0,0 +1,10 @@
+add_lldb_library(lldbPluginABISysV_riscv PLUGIN
+  ABISysV_riscv.cpp
+
+  LINK_LIBS
+    lldbCore
+    lldbSymbol
+    lldbTarget
+  LINK_COMPONENTS
+    Support
+  )
diff --git a/lldb/source/Plugins/Disassembler/llvm/DisassemblerLLVMC.cpp b/lldb/source/Plugins/Disassembler/llvm/DisassemblerLLVMC.cpp
--- a/lldb/source/Plugins/Disassembler/llvm/DisassemblerLLVMC.cpp
+++ b/lldb/source/Plugins/Disassembler/llvm/DisassemblerLLVMC.cpp
@@ -1198,6 +1198,11 @@
     cpu = "apple-latest";
   }
 
+  // For RISC-V, enable all standard extensions so these can be disassembled.
+  if (triple.getArch() == llvm::Triple::riscv32 ||
+      triple.getArch() == llvm::Triple::riscv64)
+    features_str += "+a,+c,+d,+f,+m";
+
   // We use m_disasm_up.get() to tell whether we are valid or not, so if this
   // isn't good for some reason, we won't be valid and FindPlugin will fail and
   // we won't get used.
diff --git a/lldb/source/Plugins/Process/Utility/DynamicRegisterInfo.cpp b/lldb/source/Plugins/Process/Utility/DynamicRegisterInfo.cpp
--- a/lldb/source/Plugins/Process/Utility/DynamicRegisterInfo.cpp
+++ b/lldb/source/Plugins/Process/Utility/DynamicRegisterInfo.cpp
@@ -621,6 +621,18 @@
       }
       break;
 
+    case llvm::Triple::riscv32:
+    case llvm::Triple::riscv64:
+      for (auto &reg : m_regs) {
+        if (strcmp(reg.name, "x1") == 0)
+          reg.kinds[eRegisterKindGeneric] = LLDB_REGNUM_GENERIC_RA;
+        else if (strcmp(reg.name, "x2") == 0)
+          reg.kinds[eRegisterKindGeneric] = LLDB_REGNUM_GENERIC_SP;
+        else if (strcmp(reg.name, "pc") == 0)
+          reg.kinds[eRegisterKindGeneric] = LLDB_REGNUM_GENERIC_PC;
+      }
+      break;
+
     default:
       break;
     }
diff --git a/lldb/source/Target/Platform.cpp b/lldb/source/Target/Platform.cpp
--- a/lldb/source/Target/Platform.cpp
+++ b/lldb/source/Target/Platform.cpp
@@ -1911,6 +1911,15 @@
     trap_opcode_size = sizeof(g_i386_opcode);
   } break;
 
+  case llvm::Triple::riscv32:
+  case llvm::Triple::riscv64: {
+    // FIXME: Use ebreak when c_ebreak is not available.
+    static const uint8_t g_riscv_c_opcode[] = {0x02, 0x90}; // c_ebreak
+    trap_opcode = g_riscv_c_opcode;
+    trap_opcode_size = sizeof(g_riscv_c_opcode);
+    break;
+  }
+
   default:
     llvm_unreachable(
         "Unhandled architecture in Platform::GetSoftwareBreakpointTrapOpcode");
diff --git a/lldb/source/Target/Thread.cpp b/lldb/source/Target/Thread.cpp
--- a/lldb/source/Target/Thread.cpp
+++ b/lldb/source/Target/Thread.cpp
@@ -2070,6 +2070,8 @@
     case llvm::Triple::ppc:
     case llvm::Triple::ppc64:
     case llvm::Triple::ppc64le:
+    case llvm::Triple::riscv32:
+    case llvm::Triple::riscv64:
     case llvm::Triple::systemz:
     case llvm::Triple::hexagon:
       m_unwinder_up.reset(new UnwindLLDB(*this));
diff --git a/lldb/source/Utility/ArchSpec.cpp b/lldb/source/Utility/ArchSpec.cpp
--- a/lldb/source/Utility/ArchSpec.cpp
+++ b/lldb/source/Utility/ArchSpec.cpp
@@ -210,6 +210,11 @@
     {eByteOrderLittle, 4, 4, 4, llvm::Triple::hexagon,
      ArchSpec::eCore_hexagon_hexagonv5, "hexagonv5"},
 
+    {eByteOrderLittle, 4, 2, 4, llvm::Triple::riscv32,
+     ArchSpec::eCore_riscv32, "riscv32"},
+    {eByteOrderLittle, 8, 2, 4, llvm::Triple::riscv64,
+     ArchSpec::eCore_riscv64, "riscv64"},
+
     {eByteOrderLittle, 4, 4, 4, llvm::Triple::UnknownArch,
      ArchSpec::eCore_uknownMach32, "unknown-mach-32"},
     {eByteOrderLittle, 8, 4, 4, llvm::Triple::UnknownArch,
@@ -446,6 +451,10 @@
      ArchSpec::eMIPSSubType_mips64r6el, 0xFFFFFFFFu, 0xFFFFFFFFu}, // mips64r6el
     {ArchSpec::eCore_hexagon_generic, llvm::ELF::EM_HEXAGON,
      LLDB_INVALID_CPUTYPE, 0xFFFFFFFFu, 0xFFFFFFFFu}, // HEXAGON
+    {ArchSpec::eCore_riscv32, llvm::ELF::EM_RISCV, LLDB_INVALID_CPUTYPE,
+     0xFFFFFFFFu, 0xFFFFFFFFu}, // riscv32
+    {ArchSpec::eCore_riscv64, llvm::ELF::EM_RISCV, LLDB_INVALID_CPUTYPE,
+     0xFFFFFFFFu, 0xFFFFFFFFu}, // riscv64
 };
 
 static const ArchDefinition g_elf_arch_def = {