
$FreeBSD: ports/devel/gdb6/files/patch-ppcfbsd-nat.c,v 1.1 2006/08/12 20:54:37 obrien Exp $

--- /dev/null
+++ gdb/ppcfbsd-nat.c
@@ -0,0 +1,190 @@
+/* Native-dependent code for PowerPC's running FreeBSD, for GDB.
+   Copyright 2002, 2004 Free Software Foundation, Inc.
+   Contributed by Wasabi Systems, Inc.
+
+   This file is part of GDB.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+#include <sys/types.h>
+#include <sys/ptrace.h>
+#include <machine/reg.h>
+#include <machine/frame.h>
+#include <machine/pcb.h>
+
+#include "defs.h"
+#include "inferior.h"
+#include "gdb_assert.h"
+#include "gdbcore.h"
+#include "regcache.h"
+#include "bsd-kvm.h"
+
+#include "ppc-tdep.h"
+#include "ppcfbsd-tdep.h"
+
+#include "inf-ptrace.h"
+
+/* Returns true if PT_GETREGS fetches this register.  */
+static int
+getregs_supplies (int regno)
+{
+  struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch);
+
+  return ((regno >= tdep->ppc_gp0_regnum
+           && regno < tdep->ppc_gp0_regnum + ppc_num_gprs)
+          || regno == tdep->ppc_lr_regnum
+          || regno == tdep->ppc_cr_regnum
+          || regno == tdep->ppc_xer_regnum
+          || regno == tdep->ppc_ctr_regnum
+	  || regno == PC_REGNUM);
+}
+
+/* Like above, but for PT_GETFPREGS.  */
+static int
+getfpregs_supplies (int regno)
+{
+  struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch);
+
+  /* FIXME: jimb/2004-05-05: Some PPC variants don't have floating
+     point registers.  Traditionally, GDB's register set has still
+     listed the floating point registers for such machines, so this
+     code is harmless.  However, the new E500 port actually omits the
+     floating point registers entirely from the register set --- they
+     don't even have register numbers assigned to them.
+
+     It's not clear to me how best to update this code, so this assert
+     will alert the first person to encounter the NetBSD/E500
+     combination to the problem.  */
+  gdb_assert (ppc_floating_point_unit_p (current_gdbarch));
+
+  return ((regno >= tdep->ppc_fp0_regnum
+           && regno < tdep->ppc_fp0_regnum + ppc_num_fprs)
+	  || regno == tdep->ppc_fpscr_regnum);
+}
+
+static void
+ppcfbsd_fetch_inferior_registers (int regno)
+{
+  if (regno == -1 || getregs_supplies (regno))
+    {
+      struct reg regs;
+
+      if (ptrace (PT_GETREGS, PIDGET (inferior_ptid),
+		  (PTRACE_TYPE_ARG3) &regs, 0) == -1)
+        perror_with_name (_("Couldn't get registers"));
+
+      ppcfbsd_supply_reg ((char *) &regs, regno);
+      if (regno != -1)
+	return;
+    }
+
+  if (regno == -1 || getfpregs_supplies (regno))
+    {
+      struct fpreg fpregs;
+
+      if (ptrace (PT_GETFPREGS, PIDGET (inferior_ptid),
+		  (PTRACE_TYPE_ARG3) &fpregs, 0) == -1)
+	perror_with_name (_("Couldn't get FP registers"));
+
+      ppcfbsd_supply_fpreg ((char *) &fpregs, regno);
+      if (regno != -1)
+	return;
+    }
+}
+
+static void
+ppcfbsd_store_inferior_registers (int regno)
+{
+  if (regno == -1 || getregs_supplies (regno))
+    {
+      struct reg regs;
+
+      if (ptrace (PT_GETREGS, PIDGET (inferior_ptid),
+		  (PTRACE_TYPE_ARG3) &regs, 0) == -1)
+	perror_with_name (_("Couldn't get registers"));
+
+      ppcfbsd_fill_reg ((char *) &regs, regno);
+
+      if (ptrace (PT_SETREGS, PIDGET (inferior_ptid),
+		  (PTRACE_TYPE_ARG3) &regs, 0) == -1)
+	perror_with_name (_("Couldn't write registers"));
+
+      if (regno != -1)
+	return;
+    }
+
+  if (regno == -1 || getfpregs_supplies (regno))
+    {
+      struct fpreg fpregs;
+
+      if (ptrace (PT_GETFPREGS, PIDGET (inferior_ptid),
+		  (PTRACE_TYPE_ARG3) &fpregs, 0) == -1)
+	perror_with_name (_("Couldn't get FP registers"));
+
+      ppcfbsd_fill_fpreg ((char *) &fpregs, regno);
+      
+      if (ptrace (PT_SETFPREGS, PIDGET (inferior_ptid),
+		  (PTRACE_TYPE_ARG3) &fpregs, 0) == -1)
+	perror_with_name (_("Couldn't set FP registers"));
+    }
+}
+
+static int
+ppcfbsd_supply_pcb (struct regcache *regcache, struct pcb *pcb)
+{
+  struct switchframe sf;
+  struct callframe cf;
+  struct gdbarch_tdep *tdep = gdbarch_tdep (current_gdbarch);
+  int i;
+
+  /* The stack pointer shouldn't be zero.  */
+  if (pcb->pcb_sp == 0)
+    return 0;
+
+  read_memory (pcb->pcb_sp, (char *) &sf, sizeof sf);
+  regcache_raw_supply (regcache, tdep->ppc_cr_regnum, &sf.cr);
+  regcache_raw_supply (regcache, tdep->ppc_gp0_regnum + 2, &sf.fixreg2);
+  for (i = 0 ; i < 19 ; i++)
+    regcache_raw_supply (regcache, tdep->ppc_gp0_regnum + 13 + i,
+			 &sf.fixreg[i]);
+
+  read_memory(sf.sp, (char *)&cf, sizeof(cf));
+  regcache_raw_supply (regcache, tdep->ppc_gp0_regnum + 30, &cf.cf_arg0);
+  regcache_raw_supply (regcache, tdep->ppc_gp0_regnum + 31, &cf.cf_func);
+  regcache_raw_supply (regcache, tdep->ppc_gp0_regnum + 1, &cf.cf_dummy_fp);
+
+  read_memory(cf.cf_dummy_fp, (char *)&cf, sizeof(cf));
+  regcache_raw_supply (regcache, tdep->ppc_lr_regnum, &cf.cf_lr);
+  regcache_raw_supply (regcache, PC_REGNUM, &cf.cf_lr);
+
+  return 1;
+}
+
+/* Provide a prototype to silence -Wmissing-prototypes.  */
+void _initialize_ppcfbsd_nat (void);
+
+void
+_initialize_ppcfbsd_nat (void)
+{
+  struct target_ops *t;
+  /* Support debugging kernel virtual memory images.  */
+  bsd_kvm_add_target (ppcfbsd_supply_pcb);
+  /* Add in local overrides.  */
+  t = inf_ptrace_target ();
+  t->to_fetch_registers = ppcfbsd_fetch_inferior_registers;
+  t->to_store_registers = ppcfbsd_store_inferior_registers;
+  add_target (t);
+}
