Re: [rfc][3/3] gdbserver bi-arch for ppc: enable bi-arch support

Ulrich Weigand
2008-02-28T06:03:11Z

Daniel Jacobowitz wrote:
> On Fri, Feb 08, 2008 at 02:11:22AM +0100, Ulrich Weigand wrote:
> > + /* Only if the high bit of the MSR is set, we actually have
> > + a 64-bit inferior. */
> > +#ifdef __ALTIVEC__
> > + collect_register_by_name ("msr", &msr);
> > +#else
> > + collect_register_by_name ("ps", &msr);
> > +#endif
> > + if (msr < 0)
> > + return;
> > +#endif
>
> This #ifdef can go away; in the manually written regformats files,
> calls to collect_register_by_name are the only thing that rely on
> the register name, so you could just rename it to msr.

Ah, right. I've updated the patch accordingly.

> Otherwise OK.

Thanks; I've checked in the patch below.

> > + /* OK, we have a 32-bit inferior. */
> > +#ifdef __ALTIVEC__
> > + init_registers_powerpc_32 ();
> > +#else
> > +#ifdef __SPE__
> > + init_registers_powerpc_e500 ();
> > +#else
> > + init_registers_ppc ();
> > +#endif
> > +#endif
>
> I hope we can autodetect AltiVec and SPE too... Maybe we have to
> resort to checking the inferior's auxv?

Agreed. I'll see if I can put a patch along those lines together.
However, I don't have any non-AltiVec or SPE systems available;
would you be able to test on those?

Bye,
Ulrich

ChangeLog:

* regformats/reg-ppc.dat: Rename "ps" to "msr".
* regformats/reg-ppc64.dat: Likewise.

gdbserver/ChangeLog:

* configure.srv [powerpc64-*-linux*]: Add all files mentioned for
powerpc-*-linux* to srv_regobj and reg_xmlfiles.
* linux-ppc-low.c (ppc_get_pc): Support bi-arch operation.
(ppc_set_pc): Likewise.
(ppc_arch_setup): New function.
(ppc_fill_gregset): Call ppc_collect_ptrace_register instead
of collect_register.
(the_low_target): Use ppc_arch_setup as arch_setup initializer.

diff -urNp gdb-orig/gdb/gdbserver/configure.srv gdb-head/gdb/gdbserver/configure.srv
--- gdb-orig/gdb/gdbserver/configure.srv 2008-02-28 04:44:34.000000000 +0100
+++ gdb-head/gdb/gdbserver/configure.srv 2008-02-28 06:01:43.048973708 +0100
@@ -106,12 +106,17 @@ case "${target}" in
srv_linux_usrregs=yes
srv_linux_thread_db=yes
;;
- powerpc64-*-linux*) srv_regobj="reg-ppc64.o powerpc-64.o"
+ powerpc64-*-linux*) srv_regobj="reg-ppc.o powerpc-32.o powerpc-e500.o"
+ srv_regobj="${srv_regobj} reg-ppc64.o powerpc-64.o"
srv_tgtobj="linux-low.o linux-ppc-low.o"
- srv_xmlfiles="rs6000/powerpc-64.xml"
+ srv_xmlfiles="rs6000/powerpc-32.xml"
srv_xmlfiles="${srv_xmlfiles} rs6000/power-altivec.xml"
- srv_xmlfiles="${srv_xmlfiles} rs6000/power64-core.xml"
+ srv_xmlfiles="${srv_xmlfiles} rs6000/power-core.xml"
srv_xmlfiles="${srv_xmlfiles} rs6000/power-fpu.xml"
+ srv_xmlfiles="${srv_xmlfiles} rs6000/powerpc-e500.xml"
+ srv_xmlfiles="${srv_xmlfiles} rs6000/power-spe.xml"
+ srv_xmlfiles="${srv_xmlfiles} rs6000/powerpc-64.xml"
+ srv_xmlfiles="${srv_xmlfiles} rs6000/power64-core.xml"
srv_linux_usrregs=yes
srv_linux_regsets=yes
srv_linux_thread_db=yes
diff -urNp gdb-orig/gdb/gdbserver/linux-ppc-low.c gdb-head/gdb/gdbserver/linux-ppc-low.c
--- gdb-orig/gdb/gdbserver/linux-ppc-low.c 2008-02-28 04:44:34.000000000 +0100
+++ gdb-head/gdb/gdbserver/linux-ppc-low.c 2008-02-28 06:03:17.532729696 +0100
@@ -138,18 +138,65 @@ ppc_supply_ptrace_register (int regno, c
static CORE_ADDR
ppc_get_pc (void)
{
- unsigned long pc;
-
- collect_register_by_name ("pc", &pc);
- return (CORE_ADDR) pc;
+ if (register_size (0) == 4)
+ {
+ unsigned int pc;
+ collect_register_by_name ("pc", &pc);
+ return (CORE_ADDR) pc;
+ }
+ else
+ {
+ unsigned long pc;
+ collect_register_by_name ("pc", &pc);
+ return (CORE_ADDR) pc;
+ }
}

static void
ppc_set_pc (CORE_ADDR pc)
{
- unsigned long newpc = pc;
+ if (register_size (0) == 4)
+ {
+ unsigned int newpc = pc;
+ supply_register_by_name ("pc", &newpc);
+ }
+ else
+ {
+ unsigned long newpc = pc;
+ supply_register_by_name ("pc", &newpc);
+ }
+}
+
+static void
+ppc_arch_setup (void)
+{
+#ifdef __powerpc64__
+ long msr;

- supply_register_by_name ("pc", &newpc);
+ /* On a 64-bit host, assume 64-bit inferior process. */
+#ifdef __ALTIVEC__
+ init_registers_powerpc_64 ();
+#else
+ init_registers_ppc64 ();
+#endif
+
+ /* Only if the high bit of the MSR is set, we actually have
+ a 64-bit inferior. */
+ collect_register_by_name ("msr", &msr);
+ if (msr < 0)
+ return;
+#endif
+
+ /* OK, we have a 32-bit inferior. */
+#ifdef __ALTIVEC__
+ init_registers_powerpc_32 ();
+#else
+#ifdef __SPE__
+ init_registers_powerpc_e500 ();
+#else
+ init_registers_ppc ();
+#endif
+#endif
}

/* Correct in either endianness.
@@ -179,10 +226,10 @@ static void ppc_fill_gregset (void *buf)
int i;

for (i = 0; i < 32; i++)
- collect_register (i, (char *) buf + ppc_regmap[i]);
+ ppc_collect_ptrace_register (i, (char *) buf + ppc_regmap[i]);

for (i = 64; i < 70; i++)
- collect_register (i, (char *) buf + ppc_regmap[i]);
+ ppc_collect_ptrace_register (i, (char *) buf + ppc_regmap[i]);
}

#ifdef __ALTIVEC__
@@ -285,23 +332,7 @@ struct regset_info target_regsets[] = {
};

struct linux_target_ops the_low_target = {
-#ifdef __powerpc64__
-#ifdef __ALTIVEC__
- init_registers_powerpc_64,
-#else
- init_registers_ppc64,
-#endif
-#else
-#ifdef __ALTIVEC__
- init_registers_powerpc_32,
-#else
-#ifdef __SPE__
- init_registers_powerpc_e500,
-#else
- init_registers_ppc,
-#endif
-#endif
-#endif
+ ppc_arch_setup,
ppc_num_regs,
ppc_regmap,
ppc_cannot_fetch_register,
diff -urNp gdb-orig/gdb/regformats/reg-ppc64.dat gdb-head/gdb/regformats/reg-ppc64.dat
--- gdb-orig/gdb/regformats/reg-ppc64.dat 2008-02-27 23:18:38.000000000 +0100
+++ gdb-head/gdb/regformats/reg-ppc64.dat 2008-02-28 06:02:20.651277210 +0100
@@ -67,7 +67,7 @@ expedite:r1,pc
64:f31

64:pc
-64:ps
+64:msr

32:cr
64:lr
diff -urNp gdb-orig/gdb/regformats/reg-ppc.dat gdb-head/gdb/regformats/reg-ppc.dat
--- gdb-orig/gdb/regformats/reg-ppc.dat 2002-04-11 22:30:08.000000000 +0200
+++ gdb-head/gdb/regformats/reg-ppc.dat 2008-02-28 06:02:06.287084193 +0100
@@ -67,7 +67,7 @@ expedite:r1,pc
64:f31

32:pc
-32:ps
+32:msr

32:cr
32:lr

--
Dr. Ulrich Weigand
GNU Toolchain for Linux on System z and Cell BE
Ulrich.Weigand@de.ibm.com