[Lldb-commits] [lldb] [lldb-dap] Don't emit memory reference for constants (PR #197645)

[Sergei Druzhkov via lldb-commits]

https://github.com/DrSergei updated https://github.com/llvm/llvm-project/pull/197645

>From e2b3583f338836a293c7e83162de21a332fb7556 Mon Sep 17 00:00:00 2001
From: Sergei Druzhkov <serzhdruzhok at gmail.com>
Date: Thu, 14 May 2026 13:02:06 +0300
Subject: [PATCH 1/2] [lldb-dap] Don't emit memory reference for constants

---
 .../API/tools/lldb-dap/evaluate/TestDAP_evaluate.py    |  1 +
 lldb/tools/lldb-dap/Handler/EvaluateRequestHandler.cpp | 10 +++++++---
 2 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/lldb/test/API/tools/lldb-dap/evaluate/TestDAP_evaluate.py b/lldb/test/API/tools/lldb-dap/evaluate/TestDAP_evaluate.py
index 556168e5adfa8..328938b42b39f 100644
--- a/lldb/test/API/tools/lldb-dap/evaluate/TestDAP_evaluate.py
+++ b/lldb/test/API/tools/lldb-dap/evaluate/TestDAP_evaluate.py
@@ -155,6 +155,7 @@ def run_test_evaluate_expressions(
         self.assertEvaluate("non_static_int", "43", want_type="int")
         self.assertEvaluate("struct1.foo", "15", want_type="int")
         self.assertEvaluate("struct2->foo", "16", want_type="int")
+        self.assertEvaluate("10", "10", want_type="int", want_memref=False)
 
         if self.isResultExpandedDescription():
             self.assertEvaluate(
diff --git a/lldb/tools/lldb-dap/Handler/EvaluateRequestHandler.cpp b/lldb/tools/lldb-dap/Handler/EvaluateRequestHandler.cpp
index 7537eca72ec25..0917da637d8f7 100644
--- a/lldb/tools/lldb-dap/Handler/EvaluateRequestHandler.cpp
+++ b/lldb/tools/lldb-dap/Handler/EvaluateRequestHandler.cpp
@@ -118,6 +118,13 @@ EvaluateRequestHandler::Run(const EvaluateArguments &arguments) const {
   if (value.GetError().Fail())
     return ToError(value.GetError(), /*show_user=*/false);
 
+  // Check original value type before calling `Persist`, because it change value
+  // type to const result
+  if (lldb::addr_t addr = value.GetLoadAddress();
+      value.GetValueType() != lldb::eValueTypeConstResult &&
+      addr != LLDB_INVALID_ADDRESS)
+    body.memoryReference = EncodeMemoryReference(addr);
+
   if (is_repl_context) {
     // save the new variable expression
     dap.last_valid_variable_expression = std::move(expression);
@@ -137,9 +144,6 @@ EvaluateRequestHandler::Run(const EvaluateArguments &arguments) const {
     body.variablesReference = dap.reference_storage.Insert(
         value, /*is_permanent=*/is_repl_context, /*is_internal=*/false);
 
-  if (lldb::addr_t addr = value.GetLoadAddress(); addr != LLDB_INVALID_ADDRESS)
-    body.memoryReference = EncodeMemoryReference(addr);
-
   if (ValuePointsToCode(value) &&
       body.variablesReference.Kind() != eReferenceKindInvalid)
     body.valueLocationReference =

>From ced9c1365115a0ffdde412dcfc8e0ecc4bf617ad Mon Sep 17 00:00:00 2001
From: Sergei Druzhkov <serzhdruzhok at gmail.com>
Date: Fri, 15 May 2026 12:52:57 +0300
Subject: [PATCH 2/2] Fix review comments

---
 lldb/tools/lldb-dap/Handler/EvaluateRequestHandler.cpp | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/lldb/tools/lldb-dap/Handler/EvaluateRequestHandler.cpp b/lldb/tools/lldb-dap/Handler/EvaluateRequestHandler.cpp
index 0917da637d8f7..8cd33f7458ae6 100644
--- a/lldb/tools/lldb-dap/Handler/EvaluateRequestHandler.cpp
+++ b/lldb/tools/lldb-dap/Handler/EvaluateRequestHandler.cpp
@@ -118,11 +118,11 @@ EvaluateRequestHandler::Run(const EvaluateArguments &arguments) const {
   if (value.GetError().Fail())
     return ToError(value.GetError(), /*show_user=*/false);
 
-  // Check original value type before calling `Persist`, because it change value
-  // type to const result
+  // Check the original value type before calling `Persist`, because it changes
+  // the type to const result
   if (lldb::addr_t addr = value.GetLoadAddress();
-      value.GetValueType() != lldb::eValueTypeConstResult &&
-      addr != LLDB_INVALID_ADDRESS)
+      addr != LLDB_INVALID_ADDRESS &&
+      value.GetValueType() != lldb::eValueTypeConstResult)
     body.memoryReference = EncodeMemoryReference(addr);
 
   if (is_repl_context) {