Re: your turn :-)

[Joel Brobecker <brobecker@gnat.com>]

I'll see if I can take care of this. Right now, GDB is completely
broken again. This change sort of patch things up a little bit
by preventing a SEGV. But we get some other problems that just
screw the testsuite run.


    Index: mips-tdep.c
    ===================================================================
    RCS file: /cvs/src/src/gdb/mips-tdep.c,v
    retrieving revision 1.320
    diff -u -p -r1.320 mips-tdep.c
    --- mips-tdep.c	4 Sep 2004 00:16:56 -0000	1.320
    +++ mips-tdep.c	4 Sep 2004 18:59:18 -0000
    @@ -2762,9 +2762,17 @@ mips32_heuristic_proc_desc (CORE_ADDR st
     {
       CORE_ADDR cur_pc;
       CORE_ADDR frame_addr = 0;	/* Value of $r30. Used by gcc for frame-pointer */
    +
    +  /* FIXME: brobecker/2004-09-04: We're in the middle of a transition,
    +     and this_cache may be NULL. In that case, then create a new one
    +     just for now. It means a memory leak, but oh well, I don't care.  */
    +  if (this_cache == NULL)
    +    this_cache = FRAME_OBSTACK_ZALLOC (struct mips_frame_cache);
    +
     restart:
    -  this_cache = xrealloc (this_cache, SIZEOF_FRAME_SAVED_REGS);
    -  memset (this_cache, '\0', SIZEOF_FRAME_SAVED_REGS);
    +  this_cache->saved_regs = xrealloc (this_cache->saved_regs,
    +                                     SIZEOF_FRAME_SAVED_REGS);
    +  memset (this_cache->saved_regs, '\0', SIZEOF_FRAME_SAVED_REGS);
       PROC_FRAME_OFFSET (&temp_proc_desc) = 0;
       PROC_FRAME_ADJUST (&temp_proc_desc) = 0;	/* offset of FP from SP */
       for (cur_pc = start_pc; cur_pc < limit_pc; cur_pc += MIPS_INSTLEN)

I guess you really don't want to see me incorporate my last RFA
until the cleanup is done, eh?


On Fri, Sep 03, 2004 at 08:11:36PM -0400, Andrew Cagney wrote:
> Joel
> 
> The theory is to enable this:
> 
> #ifdef NOT_YET
>     proc_desc = heuristic_proc_desc (start_addr, pc, next_frame, 
> this_cache);
> #else
>     proc_desc = heuristic_proc_desc (start_addr, pc, next_frame, NULL);
> #endif

What should heuristic_proc_desc do if the cache given is NULL.
Create a temporary one while scaning the function, and then
trash it?

Another question that's troubling me: I can't see how mips_frame_cache
structs are deallocated. I am guessing that this happens when the
obstack is reset, but then that would mean that we leak the save_regs
array. ???

> Then:
> 
> - delete the rest of the insn{32,16}_frame_cache code as its redundant, 
> the heuristic code will have already updated the cache
> 
> - eliminate proc_desc from mips{32,16}_heuristic ... as its redundant, 
> the code only needs to update this_cache
> 
> - either inline mips{32,16}_heuristic into mips_insn{32,16}_frame_cache 
> or, instead, merge mips_insn{32,16}_frame_cache.
> 
> want to try it (the test results don't even need to vaguely pass).
> 
> Andrew

Hafta run.
-- 
Joel