[lldb][NFCI] Change return type of DWARFDebugInfoEntry::GetAttributes

The purpose of this method is to get the list of attributes of a
DebugInfoEntry. Prior to this change we were passing in a mutable
reference to a DWARFAttributes object and having the method fill it in
for us while returning the size of the filled out list. But
instead of doing that, we can just return a `DWARFAttributes` object
ourselves since every caller creates a new list before calling
GetAttributes.

Differential Revision: https://reviews.llvm.org/D150402

Author: bulbazord

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

@@ -31,71 +31,70 @@ DWARFASTParser::ParseChildArrayInfo(const DWARFDIE &parent_die,
     if (tag != DW_TAG_subrange_type)
       continue;
 
-    DWARFAttributes attributes;
-    const size_t num_child_attributes = die.GetAttributes(attributes);
-    if (num_child_attributes > 0) {
-      uint64_t num_elements = 0;
-      uint64_t lower_bound = 0;
-      uint64_t upper_bound = 0;
-      bool upper_bound_valid = false;
-      uint32_t i;
-      for (i = 0; i < num_child_attributes; ++i) {
-        const dw_attr_t attr = attributes.AttributeAtIndex(i);
-        DWARFFormValue form_value;
-        if (attributes.ExtractFormValueAtIndex(i, form_value)) {
-          switch (attr) {
-          case DW_AT_name:
-            break;
-
-          case DW_AT_count:
-            if (DWARFDIE var_die = die.GetReferencedDIE(DW_AT_count)) {
-              if (var_die.Tag() == DW_TAG_variable)
-                if (exe_ctx) {
-                  if (auto frame = exe_ctx->GetFrameSP()) {
-                    Status error;
-                    lldb::VariableSP var_sp;
-                    auto valobj_sp = frame->GetValueForVariableExpressionPath(
-                        var_die.GetName(), eNoDynamicValues, 0, var_sp, error);
-                    if (valobj_sp) {
-                      num_elements = valobj_sp->GetValueAsUnsigned(0);
-                      break;
-                    }
+    DWARFAttributes attributes = die.GetAttributes();
+    if (attributes.Size() == 0)
+      continue;
+
+    uint64_t num_elements = 0;
+    uint64_t lower_bound = 0;
+    uint64_t upper_bound = 0;
+    bool upper_bound_valid = false;
+    for (size_t i = 0; i < attributes.Size(); ++i) {
+      const dw_attr_t attr = attributes.AttributeAtIndex(i);
+      DWARFFormValue form_value;
+      if (attributes.ExtractFormValueAtIndex(i, form_value)) {
+        switch (attr) {
+        case DW_AT_name:
+          break;
+
+        case DW_AT_count:
+          if (DWARFDIE var_die = die.GetReferencedDIE(DW_AT_count)) {
+            if (var_die.Tag() == DW_TAG_variable)
+              if (exe_ctx) {
+                if (auto frame = exe_ctx->GetFrameSP()) {
+                  Status error;
+                  lldb::VariableSP var_sp;
+                  auto valobj_sp = frame->GetValueForVariableExpressionPath(
+                      var_die.GetName(), eNoDynamicValues, 0, var_sp, error);
+                  if (valobj_sp) {
+                    num_elements = valobj_sp->GetValueAsUnsigned(0);
+                    break;
                   }
                 }
-            } else
-              num_elements = form_value.Unsigned();
-            break;
-
-          case DW_AT_bit_stride:
-            array_info.bit_stride = form_value.Unsigned();
-            break;
-
-          case DW_AT_byte_stride:
-            array_info.byte_stride = form_value.Unsigned();
-            break;
-
-          case DW_AT_lower_bound:
-            lower_bound = form_value.Unsigned();
-            break;
-
-          case DW_AT_upper_bound:
-            upper_bound_valid = true;
-            upper_bound = form_value.Unsigned();
-            break;
-
-          default:
-            break;
-          }
-        }
-      }
+              }
+          } else
+            num_elements = form_value.Unsigned();
+          break;
+
+        case DW_AT_bit_stride:
+          array_info.bit_stride = form_value.Unsigned();
+          break;
 
-      if (num_elements == 0) {
-        if (upper_bound_valid && upper_bound >= lower_bound)
-          num_elements = upper_bound - lower_bound + 1;
+        case DW_AT_byte_stride:
+          array_info.byte_stride = form_value.Unsigned();
+          break;
+
+        case DW_AT_lower_bound:
+          lower_bound = form_value.Unsigned();
+          break;
+
+        case DW_AT_upper_bound:
+          upper_bound_valid = true;
+          upper_bound = form_value.Unsigned();
+          break;
+
+        default:
+          break;
+        }
       }
+    }
 
-      array_info.element_orders.push_back(num_elements);
+    if (num_elements == 0) {
+      if (upper_bound_valid && upper_bound >= lower_bound)
+        num_elements = upper_bound - lower_bound + 1;
     }
+
+    array_info.element_orders.push_back(num_elements);
   }
   return array_info;
 }