[v2,3/5] jit: make gdb_object::symtabs an std::forward_list
Commit Message
Replace the manual linked list with an std::forward_list, simplifying
the memory management. This requires allocating gdb_object with new and
free'ing it with delete.
gdb/ChangeLog:
* jit.c: Include forward_list.
(struct gdb_symtab) <next>: Remove field.
(struct gdb_object) <symtabs>: Change type to
std::forward_list<gdb_symtab>.
(jit_object_open_impl): Allocate gdb_object with new.
(jit_symtab_open_impl): Adjust to std::forward_list.
(finalize_symtab): Don't delete symtab.
(jit_object_close_impl): Adjust to std::forward_list. Free
gdb_object with delete.
---
gdb/jit.c | 34 ++++++++++++++++------------------
1 file changed, 16 insertions(+), 18 deletions(-)
@@ -41,6 +41,7 @@
#include "gdb_bfd.h"
#include "readline/tilde.h"
#include "completer.h"
+#include <forward_list>
static std::string jit_reader_dir;
@@ -481,15 +482,19 @@ struct gdb_symtab
/* The source file for this symtab. */
std::string file_name;
-
- struct gdb_symtab *next = nullptr;
};
/* Proxy object for building an object. */
struct gdb_object
{
- struct gdb_symtab *symtabs;
+ /* Symtabs of this object.
+
+ This is specifically a linked list, instead of, for example, a vector,
+ because the pointers are returned to the user's debug info reader. So
+ it's important that the objects don't change location during their
+ lifetime (which would happen with a vector of objects getting resized). */
+ std::forward_list<gdb_symtab> symtabs;
};
/* The type of the `private' data passed around by the callback
@@ -521,7 +526,7 @@ jit_object_open_impl (struct gdb_symbol_callbacks *cb)
/* CB is not required right now, but sometime in the future we might
need a handle to it, and we'd like to do that without breaking
the ABI. */
- return XCNEW (struct gdb_object);
+ return new gdb_object;
}
/* Readers call into this function to open a new gdb_symtab, which,
@@ -534,10 +539,8 @@ jit_symtab_open_impl (struct gdb_symbol_callbacks *cb,
{
/* CB stays unused. See comment in jit_object_open_impl. */
- gdb_symtab *ret = new gdb_symtab (file_name);
- ret->next = object->symtabs;
- object->symtabs = ret;
- return ret;
+ object->symtabs.emplace_front (file_name);
+ return &object->symtabs.front ();
}
/* Returns true if the block corresponding to old should be placed
@@ -774,8 +777,6 @@ finalize_symtab (struct gdb_symtab *stab, struct objfile *objfile)
BLOCKVECTOR_BLOCK (bv, STATIC_BLOCK);
}
}
-
- delete stab;
}
/* Called when closing a gdb_objfile. Converts OBJ to a proper
@@ -785,7 +786,6 @@ static void
jit_object_close_impl (struct gdb_symbol_callbacks *cb,
struct gdb_object *obj)
{
- struct gdb_symtab *i, *j;
struct objfile *objfile;
jit_dbg_reader_data *priv_data;
@@ -795,14 +795,12 @@ jit_object_close_impl (struct gdb_symbol_callbacks *cb,
OBJF_NOT_FILENAME);
objfile->per_bfd->gdbarch = target_gdbarch ();
- j = NULL;
- for (i = obj->symtabs; i; i = j)
- {
- j = i->next;
- finalize_symtab (i, objfile);
- }
+ for (gdb_symtab &symtab : obj->symtabs)
+ finalize_symtab (&symtab, objfile);
+
add_objfile_entry (objfile, *priv_data);
- xfree (obj);
+
+ delete obj;
}
/* Try to read CODE_ENTRY using the loaded jit reader (if any).