[lldb] Avoid repeated map lookups (NFC)

[kazutakahirata]

No description provided.

[llvmbot]

@llvm/pr-subscribers-lldb

Author: Kazu Hirata (kazutakahirata)

Changes

---

Full diff: https://github.com/llvm/llvm-project/pull/123892.diff

1 Files Affected:

• (modified) lldb/source/Target/Process.cpp (+5-10)

diff --git a/lldb/source/Target/Process.cpp b/lldb/source/Target/Process.cpp
index c47e728fdf716c..89731f798deda8 100644
--- a/lldb/source/Target/Process.cpp
+++ b/lldb/source/Target/Process.cpp
@@ -1292,17 +1292,12 @@ bool Process::HasAssignedIndexIDToThread(uint64_t thread_id) {
 }
 
 uint32_t Process::AssignIndexIDToThread(uint64_t thread_id) {
-  uint32_t result = 0;
-  std::map<uint64_t, uint32_t>::iterator iterator =
-      m_thread_id_to_index_id_map.find(thread_id);
-  if (iterator == m_thread_id_to_index_id_map.end()) {
-    result = ++m_thread_index_id;
-    m_thread_id_to_index_id_map[thread_id] = result;
-  } else {
-    result = iterator->second;
-  }
+  auto [iterator, inserted] =
+      m_thread_id_to_index_id_map.try_emplace(thread_id, m_thread_index_id + 1);
+  if (inserted)
+    ++m_thread_index_id;
 
-  return result;
+  return iterator->second;
 }
 
 StateType Process::GetState() {