gdb: New API for tracking innermost block

This commit is preparation for a later change, at this point there
should be no user visible change.

We currently maintain a global innermost_block which tracks the most
inner block encountered when parsing an expression.

This commit wraps the innermost_block into a new class, and switches all
direct accesses to the variable to use the class API.

gdb/ChangeLog:

	* ada-exp.y (write_var_from_sym): Switch to innermost_block API.
	* ada-lang.c (resolve_subexp): Likewise.
	* breakpoint.c (set_breakpoint_condition) Likewise.
	(watch_command_1) Likewise.
	* c-exp.y (variable): Likewise.
	* d-exp.y (PrimaryExpression): Likewise.
	* f-exp.y (variable): Likewise.
	* go-exp.y (variable): Likewise.
	* m2-exp.y (variable): Likewise.
	* objfiles.c (objfile::~objfile): Likewise.
	* p-exp.y (variable): Likewise.
	* parse.c (innermost_block): Change type.
	* parser-defs.h (class innermost_block_tracker): New.
	(innermost_block): Change to innermost_block_tracker.
	* printcmd.c (display_command): Switch to innermost_block API.
	(do_one_display): Likewise.
	* rust-exp.y (do_one_display): Likewise.
	* symfile.c (clear_symtab_users): Likewise.
	* varobj.c (varobj_create): Switch to innermost_block API, replace
	use of innermost_block with block stored on varobj object.

1 files changed, 2 insertions, 10 deletions

diff --git a/gdb/p-exp.y b/gdb/p-exp.y
index 95a6924..6b857e1 100644
--- a/gdb/p-exp.y
+++ b/gdb/p-exp.y
@@ -709,12 +709,7 @@ variable:	name_not_typename
 			  if (sym.symbol)
 			    {
 			      if (symbol_read_needs_frame (sym.symbol))
-				{
-				  if (innermost_block == 0
-				      || contained_in (sym.block,
-						       innermost_block))
-				    innermost_block = sym.block;
-				}
+				innermost_block.update (sym);
 
 			      write_exp_elt_opcode (pstate, OP_VAR_VALUE);
 			      write_exp_elt_block (pstate, sym.block);
@@ -728,10 +723,7 @@ variable:	name_not_typename
 			      /* Object pascal: it hangs off of `this'.  Must
 			         not inadvertently convert from a method call
 				 to data ref.  */
-			      if (innermost_block == 0
-				  || contained_in (sym.block,
-						   innermost_block))
-				innermost_block = sym.block;
+			      innermost_block.update (sym);
 			      write_exp_elt_opcode (pstate, OP_THIS);
 			      write_exp_elt_opcode (pstate, OP_THIS);
 			      write_exp_elt_opcode (pstate, STRUCTOP_PTR);