[Lldb-commits] [lldb] [lldb][DWARF] Delay struct/class/union definition DIE searching when parsing declaration DIEs. (PR #90663)

[David Blaikie via lldb-commits]

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@@ -16,61 +16,66 @@ using namespace lldb_private::plugin::dwarf;
 bool UniqueDWARFASTTypeList::Find(const DWARFDIE &die,
                                   const lldb_private::Declaration &decl,
                                   const int32_t byte_size,
+                                  bool is_forward_declaration,
                                   UniqueDWARFASTType &entry) const {
   for (const UniqueDWARFASTType &udt : m_collection) {
     // Make sure the tags match
     if (udt.m_die.Tag() == die.Tag()) {
-      // Validate byte sizes of both types only if both are valid.
-      if (udt.m_byte_size < 0 || byte_size < 0 ||
-          udt.m_byte_size == byte_size) {
-        // Make sure the file and line match
-        if (udt.m_declaration == decl) {
-          // The type has the same name, and was defined on the same file and
-          // line. Now verify all of the parent DIEs match.
-          DWARFDIE parent_arg_die = die.GetParent();
-          DWARFDIE parent_pos_die = udt.m_die.GetParent();
-          bool match = true;
-          bool done = false;
-          while (!done && match && parent_arg_die && parent_pos_die) {
-            const dw_tag_t parent_arg_tag = parent_arg_die.Tag();
-            const dw_tag_t parent_pos_tag = parent_pos_die.Tag();
-            if (parent_arg_tag == parent_pos_tag) {
-              switch (parent_arg_tag) {
-              case DW_TAG_class_type:
-              case DW_TAG_structure_type:
-              case DW_TAG_union_type:
-              case DW_TAG_namespace: {
-                const char *parent_arg_die_name = parent_arg_die.GetName();
-                if (parent_arg_die_name ==
-                    nullptr) // Anonymous (i.e. no-name) struct
-                {
-                  match = false;
-                } else {
-                  const char *parent_pos_die_name = parent_pos_die.GetName();
-                  if (parent_pos_die_name == nullptr ||
-                      ((parent_arg_die_name != parent_pos_die_name) &&
-                       strcmp(parent_arg_die_name, parent_pos_die_name)))
-                    match = false;
-                }
-              } break;
-
-              case DW_TAG_compile_unit:
-              case DW_TAG_partial_unit:
-                done = true;
-                break;
-              default:
-                break;
-              }
+      // If they are not both definition DIEs or both declaration DIEs, then
+      // don't check for byte size and declaration location, because declaration
+      // DIEs usually don't have those info.
+      bool matching_size_declaration =
+          udt.m_is_forward_declaration != is_forward_declaration
+              ? true
+              : (udt.m_byte_size < 0 || byte_size < 0 ||
+                 udt.m_byte_size == byte_size) &&
+                    udt.m_declaration == decl;
+      if (!matching_size_declaration)
+        continue;
+      // The type has the same name, and was defined on the same file and
+      // line. Now verify all of the parent DIEs match.
+      DWARFDIE parent_arg_die = die.GetParent();
+      DWARFDIE parent_pos_die = udt.m_die.GetParent();
+      bool match = true;
+      bool done = false;
+      while (!done && match && parent_arg_die && parent_pos_die) {
+        const dw_tag_t parent_arg_tag = parent_arg_die.Tag();
+        const dw_tag_t parent_pos_tag = parent_pos_die.Tag();
+        if (parent_arg_tag == parent_pos_tag) {
+          switch (parent_arg_tag) {
+          case DW_TAG_class_type:
+          case DW_TAG_structure_type:
+          case DW_TAG_union_type:
+          case DW_TAG_namespace: {
+            const char *parent_arg_die_name = parent_arg_die.GetName();
+            if (parent_arg_die_name ==
+                nullptr) // Anonymous (i.e. no-name) struct
+            {
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dwblaikie wrote:

The comment between the `)` and `{` creates some weird line wrapping, maybe put the comment inside the `{` block?

https://github.com/llvm/llvm-project/pull/90663