target_stack -> current_top_target() throughout

The recent C++ification of target_ops replaced references to the old
"current_target" squashed target throughout with references to a
"target_stack" pointer.  I had picked the "target_stack" name very
early in the multi-target work, and managed to stick with it, even
though it's a bit of a misnomer, since it isn't really a "target
stack" object, but a pointer into the current top target in the stack.
As I'm splitting more pieces off of the multi-target branch, I've come
to think that it's better to rename it now.  A following patch will
introduce a new class to represent a target stack, and "target_stack"
would be _its_ ideal name.  (In the branch, the class is called
a_target_stack to work around the clash.)

Thus this commit renames target_stack to current_top_target and
replaces all references throughout.  Also, while at it,
current_top_target is made a function instead of a pointer, to make it
possible to change its internal implementation without leaking
implementation details out.  In a couple patches, the implementation
of the function will change to refer to a target stack object, and
then further down the multi-target work, it'll change again to find
the right target stack for the current inferior.

gdb/ChangeLog:
2018-06-07  Pedro Alves  <palves@redhat.com>

	* target.h (target_stack): Delete.
	(current_top_target): Declare function.
	* target.c (target_stack): Delete.
	(g_current_top_target): New.
	(current_top_target): New function.
	* auxv.c: Use current_top_target instead of target_stack
	throughout.
	* avr-tdep.c: Likewise.
	* breakpoint.c: Likewise.
	* corefile.c: Likewise.
	* elfread.c: Likewise.
	* eval.c: Likewise.
	* exceptions.c: Likewise.
	* frame.c: Likewise.
	* gdbarch-selftests.c: Likewise.
	* gnu-v3-abi.c: Likewise.
	* ia64-tdep.c: Likewise.
	* ia64-vms-tdep.c: Likewise.
	* infcall.c: Likewise.
	* infcmd.c: Likewise.
	* infrun.c: Likewise.
	* linespec.c: Likewise.
	* linux-tdep.c: Likewise.
	* minsyms.c: Likewise.
	* ppc-linux-nat.c: Likewise.
	* ppc-linux-tdep.c: Likewise.
	* procfs.c: Likewise.
	* regcache.c: Likewise.
	* remote.c: Likewise.
	* rs6000-tdep.c: Likewise.
	* s390-linux-nat.c: Likewise.
	* s390-tdep.c: Likewise.
	* solib-aix.c: Likewise.
	* solib-darwin.c: Likewise.
	* solib-dsbt.c: Likewise.
	* solib-spu.c: Likewise.
	* solib-svr4.c: Likewise.
	* solib-target.c: Likewise.
	* sparc-tdep.c: Likewise.
	* sparc64-tdep.c: Likewise.
	* spu-tdep.c: Likewise.
	* symfile.c: Likewise.
	* symtab.c: Likewise.
	* target-descriptions.c: Likewise.
	* target-memory.c: Likewise.
	* target.c: Likewise.
	* target.h: Likewise.
	* tracefile-tfile.c: Likewise.
	* tracepoint.c: Likewise.
	* valops.c: Likewise.
	* valprint.c: Likewise.
	* value.c: Likewise.
	* windows-tdep.c: Likewise.
	* mi/mi-main.c: Likewise.

1 files changed, 6 insertions, 6 deletions

diff --git a/gdb/remote.c b/gdb/remote.c
index 3013fbe..6d32da7 100644
--- a/gdb/remote.c
+++ b/gdb/remote.c
@@ -4924,7 +4924,7 @@ remote_target::remote_check_symbols ()
 	     instead of any data function descriptor.  */
 	  sym_addr = gdbarch_convert_from_func_ptr_addr (target_gdbarch (),
 							 sym_addr,
-							 target_stack);
+							 current_top_target ());
 
 	  xsnprintf (msg, get_remote_packet_size (), "qSymbol:%s:%s",
 		     phex_nz (sym_addr, addr_size), &reply[8]);
@@ -11391,7 +11391,7 @@ remote_target::memory_map ()
 {
   std::vector<mem_region> result;
   gdb::optional<gdb::char_vector> text
-    = target_read_stralloc (target_stack, TARGET_OBJECT_MEMORY_MAP, NULL);
+    = target_read_stralloc (current_top_target (), TARGET_OBJECT_MEMORY_MAP, NULL);
 
   if (text)
     result = parse_memory_map (text->data ());
@@ -13580,7 +13580,7 @@ traceframe_info_up
 remote_target::traceframe_info ()
 {
   gdb::optional<gdb::char_vector> text
-    = target_read_stralloc (target_stack, TARGET_OBJECT_TRACEFRAME_INFO,
+    = target_read_stralloc (current_top_target (), TARGET_OBJECT_TRACEFRAME_INFO,
 			    NULL);
   if (text)
     return parse_traceframe_info (text->data ());
@@ -13809,7 +13809,7 @@ static void
 btrace_read_config (struct btrace_config *conf)
 {
   gdb::optional<gdb::char_vector> xml
-    = target_read_stralloc (target_stack, TARGET_OBJECT_BTRACE_CONF, "");
+    = target_read_stralloc (current_top_target (), TARGET_OBJECT_BTRACE_CONF, "");
   if (xml)
     parse_xml_btrace_conf (conf, xml->data ());
 }
@@ -14005,7 +14005,7 @@ remote_target::read_btrace (struct btrace_data *btrace,
     }
 
   gdb::optional<gdb::char_vector> xml
-    = target_read_stralloc (target_stack, TARGET_OBJECT_BTRACE, annex);
+    = target_read_stralloc (current_top_target (), TARGET_OBJECT_BTRACE, annex);
   if (!xml)
     return BTRACE_ERR_UNKNOWN;
 
@@ -14062,7 +14062,7 @@ remote_target::pid_to_exec_file (int pid)
       xsnprintf (annex, annex_size, "%x", pid);
     }
 
-  filename = target_read_stralloc (target_stack,
+  filename = target_read_stralloc (current_top_target (),
 				   TARGET_OBJECT_EXEC_FILE, annex);
 
   return filename ? filename->data () : nullptr;