Re: RFA/dwarf: Fix the GCC 2.95.3 store.exp regression for multi-register variables

[Daniel Jacobowitz <drow@mvista.com>]

On Thu, Apr 10, 2003 at 02:06:01PM -0400, Elena Zannoni wrote:
> Michael Elizabeth Chastain writes:
>  > My test bed says that this is okay.  It fixes the regression in
>  > store.exp with gcc 2.95.3 -gdwarf-2 (gcc 2.95.3 is the only compiler
>  > that puts this particular struct into a register).  And it doesn't
>  > have any regressions with any gcc v2 or v3, dwarf-2 or stabs+,
>  > on my native i686-pc-linux-gnu.
>  > 
>  > I have another PR for this, gdb/1107, that comes with a source file
>  > and an executable file.  With this patch, gdb HEAD changes from
>  > 'new bad behavior' back to 'same bad behavior as 5.3'.  Specifically,
>  > I have a structure which is in %ebx and %esi.  gdb 5.3 prints values
>  > from %ebx and %esp (the next register in 'info registers').
>  > gdb HEAD prints %ebx and something from god knows where, and
>  > gdb HEAD + patch prints %ebx and %esp again.
>  > 
>  > (I really hate it when gdb prints the wrong numbers!)
>  > 
>  > With this patch gdb is better in the store.exp case and not any
>  > worse in the gdb/1107 case.  What the heck, here's a table:
>  > 
>  >                     store.exp  gdb/1107
>  >   gdb 5.3           okay       wrong
>  >   gdb HEAD          wrong      wrong
>  >   gdb HEAD + drow   okay       wrong
>  > 
>  > So ... recommended for approval.  If it goes in then we can maybe talk
>  > about gdb/1107 some more.
>  > 
>  > Michael C
> 
> Daniel did you check this in?

Now I have.  Thanks!

>  > ===
>  > 
>  > 2003-03-12  Daniel Jacobowitz  <drow@mvista.com>
>  > 
>  > 	* dwarf2expr.h (struct dwarf_expr_context): Remove extra arguments
>  > 	to read_reg and update its comment.  Remove regnum member.
>  > 	* dwarf2expr.c (execute_stack_op): Remove memaddr and expr_lval.
>  > 	Don't call read_reg when setting in_reg.  Call read_reg to get
>  > 	the frame base if it's in a register.  Return the register number
>  > 	on the stack instead of in the context.  Remove extra arguments
>  > 	to read_reg.
>  > 	* dwarf2loc.c (dwarf_expr_read_reg): Remove extra arguments.
>  > 	(dwarf2_evaluate_loc_desc): Call value_from_register.  Expect
>  > 	the register number on the expression stack.
>  > 	(needs_frame_read_reg): Remove extra arguments.
> 

-- 
Daniel Jacobowitz
MontaVista Software                         Debian GNU/Linux Developer