Re: core regs vs. proc-service regs mess

["David S. Miller" <davem@davemloft.net>]

From: Daniel Jacobowitz <drow@false.org>
Date: Wed, 5 Apr 2006 09:23:00 -0400

> On Wed, Apr 05, 2006 at 10:25:21AM +0200, Mark Kettenis wrote:
> > >  This is completely contradictory, and I don't have any idea how to
> > >  cleanly resolve this outside of duplicating the entirety of
> > >  linux_nat_make_corefile_notes() on Linux/Sparc which is silly.
> > >
> > >  Daniel any ideas? :-) Maybe we can have a "linux_tdep" struct where we
> > >  can place a "->to_fill_core_gregset()" type method or similar?
> > 
> > What really should happen is to convert linux_nat_make_corefile_notes() to
> > use the regset_from_core_section() interface.  Unfortunately that is quite
> > a bit of work since most Linux targets don't provide that interface yet.
> 
> Shouldn't this be pretty simple: gdbarch_regset_from_core_section_p?

So something like the following patch?  I didn't know what to do with
the fpxregset stuff, I guess we'll just have to pick some random
string for that?  I couldn't find a ELF section name string assigned
to that stuff.

I tested this patch along with Linux/Sparc regset_from_core_section()
support, and it all seems to work fine.

--- linux-nat.c.~1~	2006-04-05 18:08:11.000000000 -0700
+++ linux-nat.c	2006-04-05 18:41:57.000000000 -0700
@@ -36,6 +36,7 @@
 #include "gdbthread.h"
 #include "gdbcmd.h"
 #include "regcache.h"
+#include "regset.h"
 #include "inf-ptrace.h"
 #include "auxv.h"
 #include <sys/param.h>		/* for MAXPATHLEN */
@@ -2529,15 +2530,33 @@
   gdb_fpxregset_t fpxregs;
 #endif
   unsigned long lwp = ptid_get_lwp (ptid);
+  struct gdbarch *gdbarch = current_gdbarch;
+  const struct regset *regset;
 
-  fill_gregset (&gregs, -1);
+  if (gdbarch && gdbarch_regset_from_core_section_p (gdbarch)
+      && (regset = gdbarch_regset_from_core_section (gdbarch, ".reg",
+						     sizeof gregs)) != NULL)
+    {
+      regset->collect_regset (regset, current_regcache, -1,
+			      &gregs, sizeof gregs);
+    }
+  else
+    fill_gregset (&gregs, -1);
   note_data = (char *) elfcore_write_prstatus (obfd,
 					       note_data,
 					       note_size,
 					       lwp,
 					       stop_signal, &gregs);
 
-  fill_fpregset (&fpregs, -1);
+  if (gdbarch && gdbarch_regset_from_core_section_p (gdbarch)
+      && (regset = gdbarch_regset_from_core_section (gdbarch, ".reg2",
+						     sizeof fpregs)) != NULL)
+    {
+      regset->collect_regset (regset, current_regcache, -1,
+			      &fpregs, sizeof fpregs);
+    }
+  else
+    fill_fpregset (&fpregs, -1);
   note_data = (char *) elfcore_write_prfpreg (obfd,
 					      note_data,
 					      note_size,