Re: [PATCH v2 3/3] Add native target for FreeBSD/mips.

[John Baldwin <jhb@freebsd.org>]

On Thursday, December 08, 2016 12:53:06 PM Luis Machado wrote:
> On 12/06/2016 03:00 PM, John Baldwin wrote:
> > This supports the o32 and n64 ABIs.
> >
> > gdb/ChangeLog:
> >
> > 	* Makefile.in (ALLDEPFILES): Add mips-fbsd-nat.c.
> > 	* config/mips/fbsd.mh: New file.
> > 	* configure.host: Add mips*-*-freebsd*.
> > 	* mips-fbsd-nat.c: New file.
> > ---
> >  gdb/ChangeLog           |   7 +++
> >  gdb/Makefile.in         |   1 +
> >  gdb/config/mips/fbsd.mh |   3 ++
> >  gdb/configure.host      |   1 +
> >  gdb/mips-fbsd-nat.c     | 141 ++++++++++++++++++++++++++++++++++++++++++++++++
> >  5 files changed, 153 insertions(+)
> >  create mode 100644 gdb/config/mips/fbsd.mh
> >  create mode 100644 gdb/mips-fbsd-nat.c
> >
> > diff --git a/gdb/ChangeLog b/gdb/ChangeLog
> > index 890702e..fc43f81 100644
> > --- a/gdb/ChangeLog
> > +++ b/gdb/ChangeLog
> > @@ -1,5 +1,12 @@
> >  2016-12-06  John Baldwin  <jhb@FreeBSD.org>
> >
> > +	* Makefile.in (ALLDEPFILES): Add mips-fbsd-nat.c.
> > +	* config/mips/fbsd.mh: New file.
> > +	* configure.host: Add mips*-*-freebsd*.
> > +	* mips-fbsd-nat.c: New file.
> > +
> > +2016-12-06  John Baldwin  <jhb@FreeBSD.org>
> > +
> >  	* Makefile.in (ALL_TARGET_OBS): Add mips-fbsd-tdep.o.
> >  	(ALLDEPFILES): Add mips-fbsd-tdep.c.
> >  	* configure.tgt: Add mips*-*-freebsd*.
> > diff --git a/gdb/Makefile.in b/gdb/Makefile.in
> > index e34fa4a..dee9d73 100644
> > --- a/gdb/Makefile.in
> > +++ b/gdb/Makefile.in
> > @@ -2542,6 +2542,7 @@ ALLDEPFILES = \
> >  	microblaze-linux-tdep.c \
> >  	microblaze-tdep.c \
> >  	mingw-hdep.c \
> > +	mips-fbsd-nat.c \
> >  	mips-fbsd-tdep.c \
> >  	mips-linux-nat.c \
> >  	mips-linux-tdep.c \
> > diff --git a/gdb/config/mips/fbsd.mh b/gdb/config/mips/fbsd.mh
> > new file mode 100644
> > index 0000000..f433347
> > --- /dev/null
> > +++ b/gdb/config/mips/fbsd.mh
> > @@ -0,0 +1,3 @@
> > +# Host: FreeBSD/mips
> > +NATDEPFILES= fork-child.o inf-ptrace.o fbsd-nat.o mips-fbsd-nat.o
> > +HAVE_NATIVE_GCORE_HOST = 1
> 
> I suppose you tried the gcore command for native GDB on FreeBSD/MIPS and 
> it worked fine?

It mostly does.  I can read the core fine using native GDB on MIPS, but
an x86 GDB doesn't parse the generated core correctly (though it does
parse a native core from the kernel correctly).  The issue here though
isn't really a MIPS-specific one.  Right now the FreeBSD target-dependent
code uses code from binutils to write out the prpsinfo and prstatus notes
and those write Linux-style "CORE" notes.  I have a todo to fix gcore in
gdb to write out "FreeBSD" process and thread status notes instead which
will fix this (along with a separate, but somewhat similar issue with
gdb's gcore on FreeBSD/powerpc).
 
> > +/* Determine if PT_GETREGS fetches this register.  */
> > +
> > +static bool
> > +getregs_supplies (struct gdbarch *gdbarch, int regnum)
> > +{
> > +  return ((regnum) >= MIPS_ZERO_REGNUM
> > +	  && (regnum) <= gdbarch_pc_regnum (gdbarch));
> > +}
> > +
> 
> Not sure we need the extra ()'s around regnum.

Oops, will fix.

> Otherwise i have no further comments on this one.
> 
> I'm guessing someone from binutils' side will want to validate 1/3.

Yes.

-- 
John Baldwin