[binutils-gdb] Change allocation of m_dwarf2_cus

[binutils-gdb] Change allocation of m_dwarf2_cus

[Tom Tromey]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=d09ee622ee7fb4f64e9456c600874070ca21debf

commit d09ee622ee7fb4f64e9456c600874070ca21debf
Author: Tom Tromey <tom@tromey.com>
Date:   Tue Jun 7 18:00:59 2022 -0600

    Change allocation of m_dwarf2_cus
    
    m_dwarf2_cus manually manages the 'dwarf2_cu' pointers it owns.  This
    patch simplifies the code by changing it to use unique_ptr.

Diff:
---
 gdb/dwarf2/read.c | 23 +++++++++--------------
 gdb/dwarf2/read.h |  6 ++++--
 2 files changed, 13 insertions(+), 16 deletions(-)

diff --git a/gdb/dwarf2/read.c b/gdb/dwarf2/read.c
index 848fd5627b8..d279e729db9 100644
--- a/gdb/dwarf2/read.c
+++ b/gdb/dwarf2/read.c
@@ -1476,9 +1476,6 @@ dwarf2_per_objfile::remove_all_cus ()
 {
   gdb_assert (!this->per_bfd->queue.has_value ());
 
-  for (auto pair : m_dwarf2_cus)
-    delete pair.second;
-
   m_dwarf2_cus.clear ();
 }
 
@@ -6350,7 +6347,7 @@ cutu_reader::keep ()
       /* Save this dwarf2_cu in the per_objfile.  The per_objfile owns it
 	 now.  */
       dwarf2_per_objfile *per_objfile = m_new_cu->per_objfile;
-      per_objfile->set_cu (m_this_cu, m_new_cu.release ());
+      per_objfile->set_cu (m_this_cu, std::move (m_new_cu));
     }
 }
 
@@ -23535,17 +23532,18 @@ dwarf2_per_objfile::get_cu (dwarf2_per_cu_data *per_cu)
   if (it == m_dwarf2_cus.end ())
     return nullptr;
 
-  return it->second;
+  return it->second.get ();
 }
 
 /* See read.h.  */
 
 void
-dwarf2_per_objfile::set_cu (dwarf2_per_cu_data *per_cu, dwarf2_cu *cu)
+dwarf2_per_objfile::set_cu (dwarf2_per_cu_data *per_cu,
+			    std::unique_ptr<dwarf2_cu> cu)
 {
   gdb_assert (this->get_cu (per_cu) == nullptr);
 
-  m_dwarf2_cus[per_cu] = cu;
+  m_dwarf2_cus[per_cu] = std::move (cu);
 }
 
 /* See read.h.  */
@@ -23563,14 +23561,14 @@ dwarf2_per_objfile::age_comp_units ()
   gdb_assert (!this->per_bfd->queue.has_value ());
 
   /* Start by clearing all marks.  */
-  for (auto pair : m_dwarf2_cus)
+  for (const auto &pair : m_dwarf2_cus)
     pair.second->clear_mark ();
 
   /* Traverse all CUs, mark them and their dependencies if used recently
      enough.  */
-  for (auto pair : m_dwarf2_cus)
+  for (const auto &pair : m_dwarf2_cus)
     {
-      dwarf2_cu *cu = pair.second;
+      dwarf2_cu *cu = pair.second.get ();
 
       cu->last_used++;
       if (cu->last_used <= dwarf_max_cache_age)
@@ -23580,13 +23578,12 @@ dwarf2_per_objfile::age_comp_units ()
   /* Delete all CUs still not marked.  */
   for (auto it = m_dwarf2_cus.begin (); it != m_dwarf2_cus.end ();)
     {
-      dwarf2_cu *cu = it->second;
+      dwarf2_cu *cu = it->second.get ();
 
       if (!cu->is_marked ())
 	{
 	  dwarf_read_debug_printf_v ("deleting old CU %s",
 				     sect_offset_str (cu->per_cu->sect_off));
-	  delete cu;
 	  it = m_dwarf2_cus.erase (it);
 	}
       else
@@ -23603,8 +23600,6 @@ dwarf2_per_objfile::remove_cu (dwarf2_per_cu_data *per_cu)
   if (it == m_dwarf2_cus.end ())
     return;
 
-  delete it->second;
-
   m_dwarf2_cus.erase (it);
 }
 
diff --git a/gdb/dwarf2/read.h b/gdb/dwarf2/read.h
index b58c574c2be..75dd38c0b73 100644
--- a/gdb/dwarf2/read.h
+++ b/gdb/dwarf2/read.h
@@ -28,6 +28,7 @@
 #include "dwarf2/index-cache.h"
 #include "dwarf2/mapped-index.h"
 #include "dwarf2/section.h"
+#include "dwarf2/cu.h"
 #include "filename-seen-cache.h"
 #include "gdbsupport/gdb_obstack.h"
 #include "gdbsupport/hash_enum.h"
@@ -547,7 +548,7 @@ struct dwarf2_per_objfile
   dwarf2_cu *get_cu (dwarf2_per_cu_data *per_cu);
 
   /* Set the dwarf2_cu matching PER_CU for this objfile.  */
-  void set_cu (dwarf2_per_cu_data *per_cu, dwarf2_cu *cu);
+  void set_cu (dwarf2_per_cu_data *per_cu, std::unique_ptr<dwarf2_cu> cu);
 
   /* Remove/free the dwarf2_cu matching PER_CU for this objfile.  */
   void remove_cu (dwarf2_per_cu_data *per_cu);
@@ -596,7 +597,8 @@ private:
 
   /* Map from the objfile-independent dwarf2_per_cu_data instances to the
      corresponding objfile-dependent dwarf2_cu instances.  */
-  std::unordered_map<dwarf2_per_cu_data *, dwarf2_cu *> m_dwarf2_cus;
+  std::unordered_map<dwarf2_per_cu_data *,
+		     std::unique_ptr<dwarf2_cu>> m_dwarf2_cus;
 };
 
 /* Get the dwarf2_per_objfile associated to OBJFILE.  */