From 20796f181d4b6bfa9e8d11186882167da774a262 Mon Sep 17 00:00:00 2001
From: liu-yaxue <liuyaxue1@huawei.com>
Date: Fri, 11 Jul 2025 11:49:19 +0800
Subject: [PATCH] optimize performance of data copy
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Issue: 【lldb】optimize performance of data copy between arkts and native in lldb
https://gitee.com/openharmony/third_party_llvm-project/issues/ICLMZ0

Test: use log to show the performance before and after modification

Signed-off-by: liu-yaxue <liuyaxue1@huawei.com>
---
 lldb/source/Target/MixedArkTSDebugger.cpp |  9 +--
 lldb/source/Target/MixedDebugger.cpp      | 67 ++++++++++++++---------
 2 files changed, 45 insertions(+), 31 deletions(-)

diff --git a/lldb/source/Target/MixedArkTSDebugger.cpp b/lldb/source/Target/MixedArkTSDebugger.cpp
index 40a110ecca9c..6e1137a992a5 100644
--- a/lldb/source/Target/MixedArkTSDebugger.cpp
+++ b/lldb/source/Target/MixedArkTSDebugger.cpp
@@ -20,9 +20,8 @@
 
 using namespace lldb;
 using namespace lldb_private;
-
-static const char* BackTrace = "(const char*)GetJsBacktrace()";
-static const char* DebugMessage = "(const char*)OperateJsDebugMessage(\"{0}\")";
+static const char* BackTrace = "struct DebugInput { size_t size; char *data; }; (DebugInput)GetJsBacktrace()";
+static const char* DebugMessage = "(DebugInput)OperateJsDebugMessage(\"{0}\")";
 
 MixedArkTSDebugger::MixedArkTSDebugger(const TargetSP &target_sp)
     : MixedDebugger(target_sp) {}
@@ -38,7 +37,9 @@ DataExtractorSP MixedArkTSDebugger::GetCurrentThreadBackTrace(Status &error) {
 }
 
 DataExtractorSP MixedArkTSDebugger::GetCurrentThreadOperateDebugMessageResult(const char *message, Status &error) {
-  std::string operateMessage = llvm::formatv(DebugMessage, message).str();
+  std::string operateMessage =
+      "struct DebugInput {size_t size; char *data; };" +
+      llvm::formatv(DebugMessage, message).str();
   DataExtractorSP result = ExecuteAction(operateMessage.c_str(), error);
   if (!error.Success()) {
     Log *log = GetLog(LLDBLog::MixedDebugger);
diff --git a/lldb/source/Target/MixedDebugger.cpp b/lldb/source/Target/MixedDebugger.cpp
index 3c21ac062592..fb76ba3cfd3c 100644
--- a/lldb/source/Target/MixedDebugger.cpp
+++ b/lldb/source/Target/MixedDebugger.cpp
@@ -53,35 +53,47 @@ DataExtractorSP MixedDebugger::ExecuteAction(const char* expr, Status &error) {
         return result;
       }
 
-      const size_t k_max_buf_size = 64;
-      size_t cstr_len = UINT32_MAX;
-      size_t offset = 0;
-      size_t bytes_read = 0;
+      ValueObjectSP size_vo = expr_value_sp->GetChildAtIndex(0, true);
+      ValueObjectSP data_ptr_vo = expr_value_sp->GetChildAtIndex(1, true);
+
+      if (!data_ptr_vo || !size_vo) {
+        error.SetErrorString(
+            "[ExecuteAction] Failed to get DebugInput members");
+        LLDB_LOGF(log,
+                  "[ExecuteAction] struct members missing: data=%p, size=%p",
+                  data_ptr_vo.get(), size_vo.get());
+        return result;
+      }
+
+      size_t payload_len = size_vo->GetValueAsUnsigned(0);
+      if (payload_len == 0 || payload_len >= UINT32_MAX) {
+        error.SetErrorString("[ExecuteAction] Invalid payload size");
+        LLDB_LOGF(log, "[ExecuteAction] Invalid payload size: %zu",
+                  payload_len);
+        return result;
+      }
+
       DataExtractor data;
-      while ((bytes_read = expr_value_sp->GetPointeeData(data, offset, k_max_buf_size)) > 0) {
-        const char *cstr = data.PeekCStr(0);
-        size_t len = strnlen(cstr, k_max_buf_size);
-        if (len >= cstr_len) {
-          error.SetErrorString("[MixedDebugger::ExecuteAction] result over size");
-          result->Clear();
-          return result;
-        }
-        if (!result->Append(const_cast<char*>(cstr), len)) {
-          error.SetErrorString("[MixedDebugger::ExecuteAction] result append data failed");
-          result->Clear();
-          return result;
-        }
-        if (len < k_max_buf_size) {
-          break;
-        }
-        cstr_len -= len;
-        offset += len;
+      size_t bytes_read = data_ptr_vo->GetPointeeData(data, 0, payload_len);
+      if (bytes_read < payload_len) {
+        error.SetErrorString(
+            "[ExecuteAction] Failed to read data from pointer");
+        LLDB_LOGF(log, "[ExecuteAction] Failed to read expected payload_len");
+        return result;
+      }
+
+      if (!result->Append(const_cast<uint8_t *>(data.GetDataStart()),
+                          payload_len)) {
+        error.SetErrorString("[ExecuteAction] Failed to append result data");
+        LLDB_LOGF(log, "[ExecuteAction] Failed to append result data");
+        result->Clear();
+        return result;
       }
 
-      // Add terminator to result data
-      char te = '\0';
-      if (!result->Append(&te, 1)) {
-        error.SetErrorString("[MixedDebugger::ExecuteAction] result append terminator failed");
+      char terminator = '\0';
+      if (!result->Append(&terminator, 1)) {
+        error.SetErrorString(
+            "[MixedDebugger::ExecuteAction] result append terminator failed");
         result->Clear();
         return result;
       }
@@ -89,6 +101,7 @@ DataExtractorSP MixedDebugger::ExecuteAction(const char* expr, Status &error) {
   }
   LLDB_LOGF(log,
             "[MixedDebugger::ExecuteAction] result is "
-            "%s", result->PeekCStr(0));
+            "%s",
+            result->PeekCStr(0));
   return result;
 }
-- 
Gitee