Index: lldb/include/lldb/Target/ABI.h
===================================================================
--- lldb/include/lldb/Target/ABI.h
+++ lldb/include/lldb/Target/ABI.h
@@ -21,6 +21,9 @@
 class Type;
 }
 
+// TODO
+class DynamicRegisterInfo;
+
 namespace lldb_private {
 
 class ABI : public PluginInterface {
@@ -128,6 +131,8 @@
   llvm::MCRegisterInfo &GetMCRegisterInfo() { return *m_mc_register_info_up; }
 
   virtual void AugmentRegisterInfo(RegisterInfo &info) = 0;
+  // Routine called before DynamicRegisterInfo::Finalize().
+  virtual void PreFinalizeDynamicRegisterInfo(DynamicRegisterInfo &info) {}
 
   virtual bool GetPointerReturnRegister(const char *&name) { return false; }
 
Index: lldb/source/Plugins/ABI/AArch64/ABIAArch64.h
===================================================================
--- lldb/source/Plugins/ABI/AArch64/ABIAArch64.h
+++ lldb/source/Plugins/ABI/AArch64/ABIAArch64.h
@@ -32,6 +32,7 @@
   uint32_t GetGenericNum(llvm::StringRef name) override;
 
   void AugmentRegisterInfo(lldb_private::RegisterInfo &info) override;
+  void PreFinalizeDynamicRegisterInfo(DynamicRegisterInfo &info) override;
 
   using lldb_private::MCBasedABI::MCBasedABI;
 };
Index: lldb/source/Plugins/ABI/AArch64/ABIAArch64.cpp
===================================================================
--- lldb/source/Plugins/ABI/AArch64/ABIAArch64.cpp
+++ lldb/source/Plugins/ABI/AArch64/ABIAArch64.cpp
@@ -13,6 +13,8 @@
 #include "lldb/Core/PluginManager.h"
 #include "lldb/Target/Process.h"
 
+#include "Plugins/Process/Utility/DynamicRegisterInfo.h"
+
 LLDB_PLUGIN_DEFINE(ABIAArch64)
 
 void ABIAArch64::Initialize() {
@@ -78,3 +80,45 @@
   if (!strcmp(info.name, "sp") && !info.alt_name)
     info.alt_name = "x31";
 }
+
+static uint32_t tmp_value_regs[32][2];
+
+void ABIAArch64::PreFinalizeDynamicRegisterInfo(DynamicRegisterInfo &info) {
+  uint32_t next_regnum_process = 0;
+  // TODO: use public API
+  uint32_t next_regnum_lldb = info.m_regs.size();
+  for (const lldb_private::RegisterInfo &reg : info.m_regs)
+    next_regnum_process = std::max(next_regnum_process,
+                                   reg.kinds[lldb::eRegisterKindProcessPlugin]);
+  next_regnum_process++;
+
+  lldb_private::ConstString group{"partial registers"};
+
+  // Create wN aliases for xN registers if missing.
+  for (int i = 0; i < 32; i++) {
+    std::string r64_name = llvm::formatv("x{0}", i);
+    std::string r32_name = llvm::formatv("w{0}", i);
+    const lldb_private::RegisterInfo* r64 = info.GetRegisterInfo(r64_name);
+    const lldb_private::RegisterInfo* r32 = info.GetRegisterInfo(r32_name);
+    if (r64 && !r32 && r64->byte_size == 8) {
+      lldb_private::ConstString r32_name_const{r32_name};
+      // TODO
+      tmp_value_regs[i][0] = r64->kinds[lldb::eRegisterKindProcessPlugin];
+      tmp_value_regs[i][1] = LLDB_INVALID_REGNUM;
+
+      struct lldb_private::RegisterInfo new_reg {
+        r32_name_const.AsCString(), nullptr, 4,
+            LLDB_INVALID_INDEX32, r64->encoding, r64->format,
+            {
+                LLDB_INVALID_REGNUM, LLDB_INVALID_REGNUM,
+                LLDB_INVALID_REGNUM, next_regnum_process++,
+                next_regnum_lldb++,
+            },
+            tmp_value_regs[i], nullptr,
+            nullptr, 0
+      };
+
+      info.AddRegister(new_reg, group);
+    }
+  }
+}
Index: lldb/source/Plugins/Process/Utility/DynamicRegisterInfo.h
===================================================================
--- lldb/source/Plugins/Process/Utility/DynamicRegisterInfo.h
+++ lldb/source/Plugins/Process/Utility/DynamicRegisterInfo.h
@@ -70,7 +70,8 @@
   const lldb_private::RegisterInfo *
   GetRegisterInfo(llvm::StringRef reg_name) const;
 
-protected:
+// TODO
+//protected:
   // Classes that inherit from DynamicRegisterInfo can see and modify these
   typedef std::vector<lldb_private::RegisterInfo> reg_collection;
   typedef std::vector<lldb_private::RegisterSet> set_collection;
Index: lldb/source/Plugins/Process/gdb-remote/ProcessGDBRemote.cpp
===================================================================
--- lldb/source/Plugins/Process/gdb-remote/ProcessGDBRemote.cpp
+++ lldb/source/Plugins/Process/gdb-remote/ProcessGDBRemote.cpp
@@ -453,6 +453,7 @@
   if (GetGDBServerRegisterInfo(arch_to_use))
     return;
 
+  ABISP abi_sp = ABI::FindPlugin(shared_from_this(), arch_to_use);
   char packet[128];
   uint32_t reg_offset = LLDB_INVALID_INDEX32;
   uint32_t reg_num = 0;
@@ -582,7 +583,7 @@
         // We have to make a temporary ABI here, and not use the GetABI because
         // this code gets called in DidAttach, when the target architecture
         // (and consequently the ABI we'll get from the process) may be wrong.
-        if (ABISP abi_sp = ABI::FindPlugin(shared_from_this(), arch_to_use))
+        if (abi_sp)
           abi_sp->AugmentRegisterInfo(reg_info);
 
         m_register_info_sp->AddRegister(reg_info, set_name);
@@ -595,6 +596,8 @@
   }
 
   if (m_register_info_sp->GetNumRegisters() > 0) {
+    if (abi_sp)
+      abi_sp->PreFinalizeDynamicRegisterInfo(*m_register_info_sp);
     m_register_info_sp->Finalize(GetTarget().GetArchitecture());
     return;
   }
@@ -618,6 +621,8 @@
   }
 
   // At this point, we can finalize our register info.
+  if (abi_sp)
+    abi_sp->PreFinalizeDynamicRegisterInfo(*m_register_info_sp);
   m_register_info_sp->Finalize(GetTarget().GetArchitecture());
 }
 
@@ -4704,8 +4709,12 @@
   uint32_t reg_num_remote = 0;
   uint32_t reg_num_local = 0;
   if (GetGDBServerRegisterInfoXMLAndProcess(arch_to_use, "target.xml",
-                                            reg_num_remote, reg_num_local))
+                                            reg_num_remote, reg_num_local)) {
+    ABISP abi_sp = ABI::FindPlugin(shared_from_this(), arch_to_use);
+    if (abi_sp)
+      abi_sp->PreFinalizeDynamicRegisterInfo(*m_register_info_sp);
     this->m_register_info_sp->Finalize(arch_to_use);
+  }
 
   return m_register_info_sp->GetNumRegisters() > 0;
 }
Index: lldb/test/API/functionalities/gdb_remote_client/TestGDBServerTargetXML.py
===================================================================
--- lldb/test/API/functionalities/gdb_remote_client/TestGDBServerTargetXML.py
+++ lldb/test/API/functionalities/gdb_remote_client/TestGDBServerTargetXML.py
@@ -423,3 +423,7 @@
                    ["x30 = 0x4847464544434241"])
         self.match("register read flags",
                    ["cpsr = 0x74737271"])
+
+        # test partial registers
+        self.match("register read w0",
+                   ["w0 = 0x04030201"])