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, 5 insertions, 8 deletions

diff --git a/gdb/nios2-tdep.c b/gdb/nios2-tdep.c
index acc2873..09eb6fc 100644
--- a/gdb/nios2-tdep.c
+++ b/gdb/nios2-tdep.c
@@ -2275,7 +2275,7 @@ nios2_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
   struct gdbarch *gdbarch;
   struct gdbarch_tdep *tdep;
   int i;
-  struct tdesc_arch_data *tdesc_data = NULL;
+  tdesc_arch_data_up tdesc_data;
   const struct target_desc *tdesc = info.target_desc;
 
   if (!tdesc_has_registers (tdesc))
@@ -2297,14 +2297,11 @@ nios2_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
       valid_p = 1;
       
       for (i = 0; i < NIOS2_NUM_REGS; i++)
-	valid_p &= tdesc_numbered_register (feature, tdesc_data, i,
+	valid_p &= tdesc_numbered_register (feature, tdesc_data.get (), i,
 					    nios2_reg_names[i]);
 
       if (!valid_p)
-	{
-	  tdesc_data_cleanup (tdesc_data);
-	  return NULL;
-	}
+	return NULL;
     }
 
   /* Find a candidate among the list of pre-declared architectures.  */
@@ -2384,8 +2381,8 @@ nios2_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
   /* Enable inferior call support.  */
   set_gdbarch_push_dummy_call (gdbarch, nios2_push_dummy_call);
 
-  if (tdesc_data)
-    tdesc_use_registers (gdbarch, tdesc, tdesc_data);
+  if (tdesc_data != nullptr)
+    tdesc_use_registers (gdbarch, tdesc, std::move (tdesc_data));
 
   return gdbarch;
 }