Switch TaskMapOverInt to llvm::function_ref

The function does not persist the callback, so using a lighter-weight
asbtraction seems appropriate.

Also tweak the signatures of the lambdas to match what the TaskMap
interface expects.

llvm-svn: 304924

lldb/include/lldb/Utility/TaskPool.h

@@ -10,6 +10,7 @@
 #ifndef utility_TaskPool_h_
 #define utility_TaskPool_h_
 
+#include "llvm/ADT/STLExtras.h"
 #include <functional> // for bind, function
 #include <future>
 #include <list>
@@ -86,6 +87,6 @@ template <> struct TaskPool::RunTaskImpl<> {
 // 'batch_size' numbers at a time to work on, so for very fast functions, batch
 // should be large enough to avoid too much cache line contention.
 void TaskMapOverInt(size_t begin, size_t end,
-                    std::function<void(size_t)> const &func);
+                    const llvm::function_ref<void(size_t)> &func);
 
 #endif // #ifndef utility_TaskPool_h_

lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.cpp

@@ -1958,7 +1958,7 @@ void SymbolFileDWARF::Index() {
                       &function_fullname_index, &function_method_index,
                       &function_selector_index, &objc_class_selectors_index,
                       &global_index, &type_index,
-                      &namespace_index](uint32_t cu_idx) {
+                      &namespace_index](size_t cu_idx) {
       DWARFCompileUnit *dwarf_cu = debug_info->GetCompileUnitAtIndex(cu_idx);
       if (dwarf_cu) {
         dwarf_cu->Index(
@@ -1967,10 +1967,9 @@ void SymbolFileDWARF::Index() {
             objc_class_selectors_index[cu_idx], global_index[cu_idx],
             type_index[cu_idx], namespace_index[cu_idx]);
       }
-      return cu_idx;
     };
 
-    auto extract_fn = [debug_info, &clear_cu_dies](uint32_t cu_idx) {
+    auto extract_fn = [debug_info, &clear_cu_dies](size_t cu_idx) {
       DWARFCompileUnit *dwarf_cu = debug_info->GetCompileUnitAtIndex(cu_idx);
       if (dwarf_cu) {
         // dwarf_cu->ExtractDIEsIfNeeded(false) will return zero if the

lldb/source/Utility/TaskPool.cpp

@@ -75,7 +75,7 @@ void TaskPoolImpl::Worker(TaskPoolImpl *pool) {
 }
 
 void TaskMapOverInt(size_t begin, size_t end,
-                    std::function<void(size_t)> const &func) {
+                    const llvm::function_ref<void(size_t)> &func) {
   std::atomic<size_t> idx{begin};
   size_t num_workers =
       std::min<size_t>(end, std::thread::hardware_concurrency());