[Lldb-commits] [lldb] 340bd05 - [lldb] Simplify creating RegisterSets in DynamicRegisterInfo (#208592)

[via lldb-commits]

Author: Alex Langford
Date: 2026-07-10T10:52:17-07:00
New Revision: 340bd05d5f3c5dbd8bb49618aaaf39188cd2014b

URL: https://github.com/llvm/llvm-project/commit/340bd05d5f3c5dbd8bb49618aaaf39188cd2014b
DIFF: https://github.com/llvm/llvm-project/commit/340bd05d5f3c5dbd8bb49618aaaf39188cd2014b.diff

LOG: [lldb] Simplify creating RegisterSets in DynamicRegisterInfo (#208592)

`DynamicRegisterInfo::GetRegisterSetIndexByName` is only used in
`DynamicRegisterInfo::SetRegisterInfo` so I inlined it and removed the
function. I also noticed that `m_set_names` is only used in this
function for setup, so I made it a local variable instead of a member.

Added: 
    

Modified: 
    lldb/include/lldb/Target/DynamicRegisterInfo.h
    lldb/source/Target/DynamicRegisterInfo.cpp

Removed: 
    


################################################################################
diff  --git a/lldb/include/lldb/Target/DynamicRegisterInfo.h b/lldb/include/lldb/Target/DynamicRegisterInfo.h
index ada40ce1b90bb..b5ce07d9d61e0 100644
--- a/lldb/include/lldb/Target/DynamicRegisterInfo.h
+++ b/lldb/include/lldb/Target/DynamicRegisterInfo.h
@@ -71,9 +71,6 @@ class DynamicRegisterInfo {
 
   const lldb_private::RegisterSet *GetRegisterSet(uint32_t i) const;
 
-  uint32_t GetRegisterSetIndexByName(const lldb_private::ConstString &set_name,
-                                     bool can_create);
-
   uint32_t ConvertRegisterKindToRegisterNumber(uint32_t kind,
                                                uint32_t num) const;
 
@@ -105,7 +102,6 @@ class DynamicRegisterInfo {
   typedef std::vector<lldb_private::RegisterSet> set_collection;
   typedef std::vector<uint32_t> reg_num_collection;
   typedef std::vector<reg_num_collection> set_reg_num_collection;
-  typedef std::vector<lldb_private::ConstString> name_collection;
   typedef std::map<uint32_t, reg_num_collection> reg_to_regs_map;
   typedef std::map<uint32_t, uint32_t> reg_offset_map;
 
@@ -126,7 +122,6 @@ class DynamicRegisterInfo {
   reg_collection m_regs;
   set_collection m_sets;
   set_reg_num_collection m_set_reg_nums;
-  name_collection m_set_names;
   reg_to_regs_map m_value_regs_map;
   reg_to_regs_map m_invalidate_regs_map;
   reg_offset_map m_value_reg_offset_map;

diff  --git a/lldb/source/Target/DynamicRegisterInfo.cpp b/lldb/source/Target/DynamicRegisterInfo.cpp
index 3cf89ec488f8b..5fde415dd54c7 100644
--- a/lldb/source/Target/DynamicRegisterInfo.cpp
+++ b/lldb/source/Target/DynamicRegisterInfo.cpp
@@ -47,7 +47,6 @@ void DynamicRegisterInfo::MoveFrom(DynamicRegisterInfo &&info) {
   m_regs = std::move(info.m_regs);
   m_sets = std::move(info.m_sets);
   m_set_reg_nums = std::move(info.m_set_reg_nums);
-  m_set_names = std::move(info.m_set_names);
   m_value_regs_map = std::move(info.m_value_regs_map);
   m_invalidate_regs_map = std::move(info.m_invalidate_regs_map);
 
@@ -396,6 +395,9 @@ size_t DynamicRegisterInfo::SetRegisterInfo(
     const ArchSpec &arch) {
   assert(!m_finalized);
 
+  llvm::StringMap<uint32_t> set_name_to_idx;
+  uint32_t next_idx = 0;
+
   for (auto it : llvm::enumerate(regs)) {
     uint32_t local_regnum = it.index();
     const DynamicRegisterInfo::Register &reg = it.value();
@@ -428,12 +430,22 @@ size_t DynamicRegisterInfo::SetRegisterInfo(
 
     m_regs.push_back(reg_info);
 
-    uint32_t set = GetRegisterSetIndexByName(reg.set_name, true);
-    assert(set < m_sets.size());
-    assert(set < m_set_reg_nums.size());
-    assert(set < m_set_names.size());
-    m_set_reg_nums[set].push_back(local_regnum);
-  };
+    uint32_t set_idx;
+    if (!set_name_to_idx.contains(reg.set_name)) {
+      set_idx = next_idx;
+
+      set_name_to_idx.insert({reg.set_name, next_idx++});
+      m_set_reg_nums.resize(m_set_reg_nums.size() + 1);
+      RegisterSet new_set = {reg.set_name.GetCString(), nullptr, 0, nullptr};
+      m_sets.push_back(new_set);
+    } else {
+      set_idx = set_name_to_idx.lookup(reg.set_name);
+    }
+
+    assert(set_idx < m_sets.size());
+    assert(set_idx < m_set_reg_nums.size());
+    m_set_reg_nums[set_idx].push_back(local_regnum);
+  }
 
   Finalize(arch);
   return m_regs.size();
@@ -710,22 +722,6 @@ const RegisterSet *DynamicRegisterInfo::GetRegisterSet(uint32_t i) const {
   return nullptr;
 }
 
-uint32_t
-DynamicRegisterInfo::GetRegisterSetIndexByName(const ConstString &set_name,
-                                               bool can_create) {
-  name_collection::iterator pos, end = m_set_names.end();
-  for (pos = m_set_names.begin(); pos != end; ++pos) {
-    if (*pos == set_name)
-      return std::distance(m_set_names.begin(), pos);
-  }
-
-  m_set_names.push_back(set_name);
-  m_set_reg_nums.resize(m_set_reg_nums.size() + 1);
-  RegisterSet new_set = {set_name.AsCString(nullptr), nullptr, 0, nullptr};
-  m_sets.push_back(new_set);
-  return m_sets.size() - 1;
-}
-
 uint32_t
 DynamicRegisterInfo::ConvertRegisterKindToRegisterNumber(uint32_t kind,
                                                          uint32_t num) const {
@@ -742,7 +738,6 @@ void DynamicRegisterInfo::Clear() {
   m_regs.clear();
   m_sets.clear();
   m_set_reg_nums.clear();
-  m_set_names.clear();
   m_value_regs_map.clear();
   m_invalidate_regs_map.clear();
   m_reg_data_byte_size = 0;