Change management of tdesc_arch_data

While working on something else, I noticed that tdesc_data_cleanup
took a void* parameter.  Looking more into this, I found that
tdesc_use_registers expected a transfer of ownership.

I think it's better to express this sort of thing via the type system,
when possible.  This patch changes tdesc_data_alloc to return a unique
pointer, changes tdesc_use_registers to accept an rvalue reference,
and then adapts all the users.

Note that a deleter structure is introduced to avoid having to move
tdesc_arch_data to the header file.

2020-09-17  Tom Tromey  <tromey@adacore.com>

	* tic6x-tdep.c (tic6x_gdbarch_init): Update.
	* target-descriptions.h (struct tdesc_arch_data_deleter): New.
	(tdesc_arch_data_up): New typedef.
	(tdesc_use_registers, tdesc_data_alloc): Update.
	(tdesc_data_cleanup): Don't declare.
	* target-descriptions.c (tdesc_data_alloc): Return a
	tdesc_arch_data_up.
	(tdesc_arch_data_deleter::operator()): Rename from
	tdesc_data_cleanup.  Change argument type.
	(tdesc_use_registers): Change early_data to an rvalue reference.
	(tdesc_use_registers): Don't use delete.
	* sparc-tdep.c (sparc32_gdbarch_init): Update.
	* s390-tdep.c (s390_gdbarch_init): Update.
	* rx-tdep.c (rx_gdbarch_init): Update.
	* rs6000-tdep.c (rs6000_gdbarch_init): Update.
	* riscv-tdep.c (riscv_gdbarch_init): Update.
	* or1k-tdep.c (or1k_gdbarch_init): Update.
	* nios2-tdep.c (nios2_gdbarch_init): Update.
	* nds32-tdep.c (nds32_gdbarch_init): Update.
	* mips-tdep.c (mips_gdbarch_init): Update.
	* microblaze-tdep.c (microblaze_gdbarch_init): Update.
	* m68k-tdep.c (m68k_gdbarch_init): Update.
	* i386-tdep.c (i386_gdbarch_init): Update.
	* arm-tdep.c (arm_gdbarch_init): Update.
	* arc-tdep.c (arc_tdesc_init): Update.
	(arc_gdbarch_init): Update.
	* aarch64-tdep.c (aarch64_gdbarch_init): Update.

1 files changed, 8 insertions, 9 deletions

diff --git a/gdb/arc-tdep.c b/gdb/arc-tdep.c
index 6f544bf..6878875 100644
--- a/gdb/arc-tdep.c
+++ b/gdb/arc-tdep.c
@@ -2076,7 +2076,7 @@ arc_check_for_hw_loops (const struct target_desc *tdesc,
 
 static bool
 arc_tdesc_init (struct gdbarch_info info, const struct target_desc **tdesc,
-		struct tdesc_arch_data **tdesc_data)
+		tdesc_arch_data_up *tdesc_data)
 {
   const struct target_desc *tdesc_loc = info.target_desc;
   if (arc_debug)
@@ -2125,15 +2125,15 @@ arc_tdesc_init (struct gdbarch_info info, const struct target_desc **tdesc,
   const arc_register_feature *arc_aux_reg_feature
     = determine_aux_reg_feature_set ();
 
-  struct tdesc_arch_data *tdesc_data_loc = tdesc_data_alloc ();
+  tdesc_arch_data_up tdesc_data_loc = tdesc_data_alloc ();
 
   arc_update_acc_reg_names (info.byte_order);
 
-  bool valid_p = arc_check_tdesc_feature (tdesc_data_loc,
+  bool valid_p = arc_check_tdesc_feature (tdesc_data_loc.get (),
 					  feature_core,
 					  arc_core_reg_feature);
 
-  valid_p &= arc_check_tdesc_feature (tdesc_data_loc,
+  valid_p &= arc_check_tdesc_feature (tdesc_data_loc.get (),
 				      feature_aux,
 				      arc_aux_reg_feature);
 
@@ -2141,12 +2141,11 @@ arc_tdesc_init (struct gdbarch_info info, const struct target_desc **tdesc,
     {
       if (arc_debug)
         debug_printf ("arc: Target description is not valid\n");
-      tdesc_data_cleanup (tdesc_data_loc);
       return false;
     }
 
   *tdesc = tdesc_loc;
-  *tdesc_data = tdesc_data_loc;
+  *tdesc_data = std::move (tdesc_data_loc);
 
   return true;
 }
@@ -2185,7 +2184,7 @@ static struct gdbarch *
 arc_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
 {
   const struct target_desc *tdesc;
-  struct tdesc_arch_data *tdesc_data;
+  tdesc_arch_data_up tdesc_data;
 
   if (arc_debug)
     debug_printf ("arc: Architecture initialization.\n");
@@ -2198,7 +2197,7 @@ arc_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
   gdb::unique_xmalloc_ptr<struct gdbarch_tdep> tdep
     (XCNEW (struct gdbarch_tdep));
   tdep->jb_pc = -1; /* No longjmp support by default.  */
-  tdep->has_hw_loops = arc_check_for_hw_loops (tdesc, tdesc_data);
+  tdep->has_hw_loops = arc_check_for_hw_loops (tdesc, tdesc_data.get ());
   struct gdbarch *gdbarch = gdbarch_alloc (&info, tdep.release ());
 
   /* Data types.  */
@@ -2338,7 +2337,7 @@ arc_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
 	}
     }
 
-  tdesc_use_registers (gdbarch, tdesc, tdesc_data);
+  tdesc_use_registers (gdbarch, tdesc, std::move (tdesc_data));
 
   return gdbarch;
 }