gdb/gdb-varobj-revalidate-core.patch

Re: [patch] [4/5] Types reference counting [varobj-validation]
http://sourceware.org/ml/gdb-patches/2009-04/msg00610.html

gdb/
2009-04-22  Jan Kratochvil  <jan.kratochvil@redhat.com>

	Split varobj_invalidate into a two-phased operation.
	* objfiles.c: Include varobj.h
	(free_objfile): Call varobj_invalidate.
	* parser-defs.h (exp_uses_objfile): New prototype.
	* printcmd.c (display_uses_objfile): Move the EXP checking part to ...
	* parse.c (exp_uses_objfile): ... a new function here.
	* symfile.c (new_symfile_objfile): Call varobj_revalidate.
	(reread_symbols): Call varobj_invalidate and varobj_revalidate.
	(clear_symtab_users): No longer call varobj_invalidate.
	* varobj.c: New includes objfiles.h and parser-defs.h.
	(varobj_invalidate): New parameter `objfile', comment it.
	New variable `var'.  Invalidate any varobj related to `objfile'.
	Remove unconditional invalidation of local varobjs.  Move global
	varobjs revalidation to ...
	(varobj_revalidate): ... a new function.
	* varobj.h (varobj_invalidate): Update the prototype.
	(varobj_revalidate): New prototype.

[ Cut the printcmd.c simplification/change.  ]

Index: gdb-6.8.50.20090302/gdb/objfiles.c
===================================================================
--- gdb-6.8.50.20090302.orig/gdb/objfiles.c	2009-05-10 21:36:30.000000000 +0200
+++ gdb-6.8.50.20090302/gdb/objfiles.c	2009-05-10 21:36:42.000000000 +0200
@@ -50,6 +50,7 @@
 #include "addrmap.h"
 #include "arch-utils.h"
 #include "exec.h"
+#include "varobj.h"
 
 /* Prototypes for local functions */
 
@@ -409,6 +410,7 @@ free_objfile (struct objfile *objfile)
   /* Remove any references to this objfile in the global value
      lists.  */
   preserve_values (objfile);
+  varobj_invalidate (objfile);
 
   /* First do any symbol file specific actions required when we are
      finished with a particular symbol file.  Note that if the objfile
Index: gdb-6.8.50.20090302/gdb/parse.c
===================================================================
--- gdb-6.8.50.20090302.orig/gdb/parse.c	2009-05-10 21:36:29.000000000 +0200
+++ gdb-6.8.50.20090302/gdb/parse.c	2009-05-10 21:36:42.000000000 +0200
@@ -1373,6 +1373,45 @@ parser_fprintf (FILE *x, const char *y, 
   va_end (args);
 }
 
+/* Return 1 if EXP uses OBJFILE (and will become dangling when OBJFILE
+   is unloaded), otherwise return 0.  */
+
+int
+exp_uses_objfile (struct expression *exp, struct objfile *objfile)
+{
+  int endpos;
+  const union exp_element *const elts = exp->elts;
+
+  for (endpos = exp->nelts; endpos > 0; )
+    {
+      int i, args, oplen = 0;
+
+      exp->language_defn->la_exp_desc->operator_length (exp, endpos,
+							&oplen, &args);
+      gdb_assert (oplen > 0);
+
+      i = endpos - oplen;
+      if (elts[i].opcode == OP_VAR_VALUE)
+	{
+	  const struct block *const block = elts[i + 1].block;
+	  const struct symbol *const symbol = elts[i + 2].symbol;
+	  const struct obj_section *const section =
+	    SYMBOL_OBJ_SECTION (symbol);
+
+	  /* Check objfile where is placed the code touching the variable.  */
+	  if (matching_objfiles (block_objfile (block), objfile))
+	    return 1;
+
+	  /* Check objfile where the variable itself is placed.  */
+	  if (section && section->objfile == objfile)
+	    return 1;
+	}
+      endpos -= oplen;
+    }
+
+  return 0;
+}
+
 void
 _initialize_parse (void)
 {
Index: gdb-6.8.50.20090302/gdb/parser-defs.h
===================================================================
--- gdb-6.8.50.20090302.orig/gdb/parser-defs.h	2009-05-10 21:36:27.000000000 +0200
+++ gdb-6.8.50.20090302/gdb/parser-defs.h	2009-05-10 21:36:42.000000000 +0200
@@ -299,4 +299,6 @@ extern void print_subexp_standard (struc
 
 extern void parser_fprintf (FILE *, const char *, ...) ATTR_FORMAT (printf, 2 ,3);
 
+extern int exp_uses_objfile (struct expression *exp, struct objfile *objfile);
+
 #endif /* PARSER_DEFS_H */
Index: gdb-6.8.50.20090302/gdb/symfile.c
===================================================================
--- gdb-6.8.50.20090302.orig/gdb/symfile.c	2009-05-10 21:36:29.000000000 +0200
+++ gdb-6.8.50.20090302/gdb/symfile.c	2009-05-10 21:37:51.000000000 +0200
@@ -931,6 +931,8 @@ new_symfile_objfile (struct objfile *obj
 
   /* We're done reading the symbol file; finish off complaints.  */
   clear_complaints (&symfile_complaints, 0, verbo);
+
+  varobj_revalidate ();
 }
 
 /* A helper function which returns true if OBJFILE has any debug
@@ -3261,6 +3263,7 @@ reread_symbols (void)
 	      /* Remove any references to this objfile in the global
 		 value lists.  */
 	      preserve_values (objfile);
+	      varobj_invalidate (objfile);
 
 	      /* Nuke all the state that we will re-read.  Much of the following
 	         code which sets things to NULL really is necessary to tell
@@ -3359,6 +3362,7 @@ reread_symbols (void)
 	         frameless.  */
 
 	      reinit_frame_cache ();
+	      varobj_revalidate ();
 
 	      /* Discard cleanups as symbol reading was successful.  */
 	      discard_cleanups (old_cleanups);
@@ -3739,10 +3743,6 @@ clear_symtab_users (void)
      between expressions and which ought to be reset each time.  */
   expression_context_block = NULL;
   innermost_block = NULL;
-
-  /* Varobj may refer to old symbols, perform a cleanup.  */
-  varobj_invalidate ();
-
 }
 
 static void
Index: gdb-6.8.50.20090302/gdb/varobj.c
===================================================================
--- gdb-6.8.50.20090302.orig/gdb/varobj.c	2009-05-10 21:36:27.000000000 +0200
+++ gdb-6.8.50.20090302/gdb/varobj.c	2009-05-10 21:40:55.000000000 +0200
@@ -26,6 +26,8 @@
 #include "gdbcmd.h"
 #include "block.h"
 #include "valprint.h"
+#include "objfiles.h"
+#include "parser-defs.h"
 
 #include "gdb_assert.h"
 #include "gdb_string.h"
@@ -3272,48 +3274,117 @@ When non-zero, varobj debugging is enabl
 			    &setlist, &showlist);
 }
 
-/* Invalidate the varobjs that are tied to locals and re-create the ones that
-   are defined on globals.
+/* Invalidate the varobjs that are tied to the specified OBJFILE.  Call this
+   function before you start removing OBJFILE.
+
+   Call varobj_revalidate after the OBJFILEs updates get finished.
+
    Invalidated varobjs will be always printed in_scope="invalid".  */
+
 void 
-varobj_invalidate (void)
+varobj_invalidate (struct objfile *objfile)
 {
   struct varobj **all_rootvarobj;
   struct varobj **varp;
 
   if (varobj_list (&all_rootvarobj) > 0)
-  {
-    varp = all_rootvarobj;
-    while (*varp != NULL)
-      {
-	/* Floating varobjs are reparsed on each stop, so we don't care if
-	   the presently parsed expression refers to something that's gone.  */
-	if ((*varp)->root->floating)
-	  continue;
-
-        /* global var must be re-evaluated.  */     
-        if ((*varp)->root->valid_block == NULL)
-        {
-          struct varobj *tmp_var;
-
-          /* Try to create a varobj with same expression.  If we succeed replace
-             the old varobj, otherwise invalidate it.  */
-          tmp_var = varobj_create (NULL, (*varp)->name, (CORE_ADDR) 0, USE_CURRENT_FRAME);
-          if (tmp_var != NULL) 
-            { 
-	      tmp_var->obj_name = xstrdup ((*varp)->obj_name);
-              varobj_delete (*varp, NULL, 0);
-              install_variable (tmp_var);
-            }
-          else
-              (*varp)->root->is_valid = 0;
-        }
-        else /* locals must be invalidated.  */
-          (*varp)->root->is_valid = 0;
+    {
+      varp = all_rootvarobj;
+      while (*varp != NULL)
+	{
+	  struct varobj *var = *varp;
 
-        varp++;
-      }
-  }
+	  /* Floating varobjs are reparsed on each stop, so we don't care if
+	     the presently parsed expression refers to something that's gone.
+	     */
+	  if (var->root->floating)
+	    continue;
+
+	  if (var->root->is_valid
+	      && matching_objfiles (block_objfile (var->root->valid_block),
+	                            objfile))
+	    var->root->is_valid = 0;
+	  
+	  if (var->root->is_valid
+	      && exp_uses_objfile (var->root->exp, objfile))
+	    {
+	      var->root->is_valid = 0;
+
+	      /* No one touches EXP for !IS_VALID varobj.  */
+	      xfree (var->root->exp);
+	      var->root->exp = NULL;
+	    }
+	  
+	  if (var->type && TYPE_OBJFILE (var->type) == objfile)
+	    {
+	      if (!var->root->valid_block)
+		var->root->is_valid = 0;
+	      else
+		gdb_assert (!var->root->is_valid);
+
+	      var->type = NULL;
+	    }
+
+	  if (var->value
+	      && TYPE_OBJFILE (value_type (var->value)) == objfile)
+	    {
+	      if (!var->root->valid_block)
+		var->root->is_valid = 0;
+	      else
+		gdb_assert (!var->root->is_valid);
+
+	      value_free (var->value);
+	      var->value = NULL;
+	    }
+
+	  varp++;
+	}
+    }
+  xfree (all_rootvarobj);
+}
+
+/* Recreate any global varobjs possibly previously invalidated.  If the
+   expressions are no longer evaluatable set/keep the varobj invalid.  */
+
+void 
+varobj_revalidate (void)
+{
+  struct varobj **all_rootvarobj;
+  struct varobj **varp;
+
+  if (varobj_list (&all_rootvarobj) > 0)
+    {
+      varp = all_rootvarobj;
+      while (*varp != NULL)
+	{
+	  struct varobj *var = *varp;
+
+	  /* Floating varobjs are reparsed on each stop, so we don't care if
+	     the presently parsed expression refers to something that's gone.
+	     */
+	  if (var->root->floating)
+	    continue;
+
+	  /* global var must be re-evaluated.  */     
+	  if (var->root->valid_block == NULL)
+	    {
+	      struct varobj *tmp_var;
+
+	      /* Try to create a varobj with same expression.  If we succeed
+		 replace the old varobj, otherwise invalidate it.  */
+	      tmp_var = varobj_create (NULL, var->name, 0, USE_CURRENT_FRAME);
+	      if (tmp_var != NULL) 
+		{ 
+		  tmp_var->obj_name = xstrdup (var->obj_name);
+		  varobj_delete (var, NULL, 0);
+		  install_variable (tmp_var);
+		}
+	      else
+		var->root->is_valid = 0;
+	    }
+
+	  varp++;
+	}
+    }
   xfree (all_rootvarobj);
-  return;
 }
Index: gdb-6.8.50.20090302/gdb/varobj.h
===================================================================
--- gdb-6.8.50.20090302.orig/gdb/varobj.h	2009-05-10 21:36:27.000000000 +0200
+++ gdb-6.8.50.20090302/gdb/varobj.h	2009-05-10 21:36:42.000000000 +0200
@@ -148,7 +148,9 @@ extern int varobj_list (struct varobj **
 extern VEC(varobj_update_result) *varobj_update (struct varobj **varp, 
 						 int explicit);
 
-extern void varobj_invalidate (void);
+extern void varobj_invalidate (struct objfile *objfile);
+
+extern void varobj_revalidate (void);
 
 extern int varobj_editable_p (struct varobj *var);