* Makefile.in (frv-linux-tdep.o): Add dependencies.

	* frv-linux-tdep.c: New file.
	* frv-tdep.c (struct gdbarch_tdep): Add new field
	``sigcontext_reg_addr''.
	(frv_set_sigcontext_reg_addr, frv_sigtramp,frame_cache)
	(frv_sigtramp_frame_this_id, frv_sigtramp_frame_prev_register)
	(frv_sigramp_frame_sniffer): New functions.
	(frv_sigtramp_frame_unwind): New static global.
	(frv_gdbarch_init): Hook in ABI-specific overrides.  Hook up frame
	sniffers.
	* frv-tdep.h (frv_set_sigcontext_reg_addr): New function.
	* config/frv/frv.mt (TDEPFILES): Add frv-linux-tdep.o.

1 files changed, 273 insertions, 0 deletions

diff --git a/gdb/frv-linux-tdep.c b/gdb/frv-linux-tdep.c
new file mode 100644
index 00000000000..8588cb1882c
--- /dev/null
+++ b/gdb/frv-linux-tdep.c
@@ -0,0 +1,273 @@
+/* Target-dependent code for GNU/Linux running on the Fujitsu FR-V,
+   for GDB.
+   Copyright 2004 Free Software Foundation, 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 "defs.h"
+#include "target.h"
+#include "frame.h"
+#include "osabi.h"
+#include "elf-bfd.h"
+#include "elf/frv.h"
+#include "frv-tdep.h"
+
+/* Define the size (in bytes) of an FR-V instruction.  */
+static const int frv_instr_size = 4;
+
+enum {
+  NORMAL_SIGTRAMP = 1,
+  RT_SIGTRAMP = 2
+};
+
+static int
+frv_linux_pc_in_sigtramp (CORE_ADDR pc, char *name)
+{
+  char buf[frv_instr_size];
+  LONGEST instr;
+  int retval = 0;
+
+  if (target_read_memory (pc, buf, sizeof buf) != 0)
+    return 0;
+
+  instr = extract_unsigned_integer (buf, sizeof buf);
+
+  if (instr == 0x8efc0077)	/* setlos #__NR_sigreturn, gr7 */
+    retval = NORMAL_SIGTRAMP;
+  else if (instr -= 0x8efc00ad)	/* setlos #__NR_rt_sigreturn, gr7 */
+    retval = RT_SIGTRAMP;
+  else
+    return 0;
+
+  if (target_read_memory (pc + frv_instr_size, buf, sizeof buf) != 0)
+    return 0;
+  instr = extract_unsigned_integer (buf, sizeof buf);
+  if (instr != 0xc0700000)	/* tira	gr0, 0 */
+    return 0;
+
+  /* If we get this far, we'll return a non-zero value, either
+     NORMAL_SIGTRAMP (1) or RT_SIGTRAMP (2).  */
+  return retval;
+}
+
+/* Given NEXT_FRAME, "callee" frame of the sigtramp frame that we
+   wish to decode, and REGNO, one of the frv register numbers defined
+   in frv-tdep.h, return the address of the saved register (corresponding
+   to REGNO) in the sigtramp frame.  Return -1 if the register is not
+   found in the sigtramp frame.  The magic numbers in the code below
+   were computed by examining the following kernel structs:
+
+   From arch/frvnommu/signal.c:
+
+      struct sigframe
+      {
+	      void (*pretcode)(void);
+	      int sig;
+	      struct sigcontext sc;
+	      unsigned long extramask[_NSIG_WORDS-1];
+	      uint32_t retcode[2];
+      };
+
+      struct rt_sigframe
+      {
+	      void (*pretcode)(void);
+	      int sig;
+	      struct siginfo *pinfo;
+	      void *puc;
+	      struct siginfo info;
+	      struct ucontext uc;
+	      uint32_t retcode[2];
+      };
+
+   From include/asm-frvnommu/ucontext.h:
+
+      struct ucontext {
+	      unsigned long		uc_flags;
+	      struct ucontext		*uc_link;
+	      stack_t			uc_stack;
+	      struct sigcontext	uc_mcontext;
+	      sigset_t		uc_sigmask;
+      };
+
+   From include/asm-frvnommu/sigcontext.h:
+
+      struct sigcontext {
+	      struct user_context	sc_context;
+	      unsigned long		sc_oldmask;
+      } __attribute__((aligned(8)));
+
+   From include/asm-frvnommu/registers.h:
+      struct user_int_regs
+      {
+	      unsigned long		psr;
+	      unsigned long		isr;
+	      unsigned long		ccr;
+	      unsigned long		cccr;
+	      unsigned long		lr;
+	      unsigned long		lcr;
+	      unsigned long		pc;
+	      unsigned long		__status;
+	      unsigned long		syscallno;
+	      unsigned long		orig_gr8;
+	      unsigned long		gner[2];
+	      unsigned long long	iacc[1];
+
+	      union {
+		      unsigned long	tbr;
+		      unsigned long	gr[64];
+	      };
+      };
+
+      struct user_fpmedia_regs
+      {
+	      unsigned long	fr[64];
+	      unsigned long	fner[2];
+	      unsigned long	msr[2];
+	      unsigned long	acc[8];
+	      unsigned char	accg[8];
+	      unsigned long	fsr[1];
+      };
+
+      struct user_context
+      {
+	      struct user_int_regs		i;
+	      struct user_fpmedia_regs	f;
+
+	      void *extension;
+      } __attribute__((aligned(8)));  */
+
+static CORE_ADDR
+frv_linux_sigcontext_reg_addr (struct frame_info *next_frame, int regno,
+                               CORE_ADDR *sc_addr_cache_ptr)
+{
+  CORE_ADDR sc_addr;
+
+  if (sc_addr_cache_ptr && *sc_addr_cache_ptr)
+    {
+      sc_addr = *sc_addr_cache_ptr;
+    }
+  else
+    {
+      CORE_ADDR pc, sp;
+      char buf[4];
+      int tramp_type;
+
+      pc = frame_pc_unwind (next_frame);
+      tramp_type = frv_linux_pc_in_sigtramp (pc, 0);
+
+      frame_unwind_register (next_frame, sp_regnum, buf);
+      sp = extract_unsigned_integer (buf, sizeof buf);
+
+      if (tramp_type == NORMAL_SIGTRAMP)
+	{
+	  /* For a normal sigtramp frame, the sigcontext struct starts
+	     at SP + 8.  */
+	  sc_addr = sp + 8;
+	}
+      else if (tramp_type == RT_SIGTRAMP)
+	{
+	  /* For a realtime sigtramp frame, SP + 12 contains a pointer
+	     to the a ucontext struct.  The ucontext struct contains
+	     a sigcontext struct starting 12 bytes in.  */
+	  if (target_read_memory (sp + 12, buf, sizeof buf) != 0)
+	    {
+	      warning ("Can't read realtime sigtramp frame.");
+	      return 0;
+	    }
+	  sc_addr = extract_unsigned_integer (buf, sizeof buf);
+	  sc_addr += 12;
+	}
+      else
+	internal_error (__FILE__, __LINE__, "not a signal trampoline");
+
+      if (sc_addr_cache_ptr)
+	*sc_addr_cache_ptr = sc_addr;
+    }
+
+  switch (regno)
+    {
+    case psr_regnum :
+      return sc_addr + 0;
+    /* sc_addr + 4 has "isr", the Integer Status Register.  */
+    case ccr_regnum :
+      return sc_addr + 8;
+    case cccr_regnum :
+      return sc_addr + 12;
+    case lr_regnum :
+      return sc_addr + 16;
+    case lcr_regnum :
+      return sc_addr + 20;
+    case pc_regnum :
+      return sc_addr + 24;
+    /* sc_addr + 28 is __status, the exception status.
+       sc_addr + 32 is syscallno, the syscall number or -1.
+       sc_addr + 36 is orig_gr8, the original syscall arg #1.
+       sc_addr + 40 is gner[0].
+       sc_addr + 44 is gner[1]. */
+    case iacc0h_regnum :
+      return sc_addr + 48;
+    case iacc0l_regnum :
+      return sc_addr + 52;
+    default : 
+      if (first_gpr_regnum <= regno && regno <= last_gpr_regnum)
+	return sc_addr + 56 + 4 * (regno - first_gpr_regnum);
+      else if (first_fpr_regnum <= regno && regno <= last_fpr_regnum)
+	return sc_addr + 312 + 4 * (regno - first_fpr_regnum);
+      else
+	return -1;  /* not saved. */
+    }
+}
+
+static void
+frv_linux_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
+{
+  /* When the FR-V Linux kernel calls a signal handler, the return
+     address points to a bit of code on the stack.  This function is
+     used to identify this bit of code as a signal trampoline in order
+     to support backtracing through calls to signal handlers.  */
+  set_gdbarch_pc_in_sigtramp (gdbarch, frv_linux_pc_in_sigtramp);
+  frv_set_sigcontext_reg_addr (gdbarch, frv_linux_sigcontext_reg_addr);
+}
+
+static enum gdb_osabi
+frv_linux_elf_osabi_sniffer (bfd *abfd)
+{
+  int elf_flags;
+
+  elf_flags = elf_elfheader (abfd)->e_flags;
+
+  /* Assume GNU/Linux if using the FDPIC ABI.  If/when another OS shows
+     up that uses this ABI, we'll need to start using .note sections
+     or some such.  */
+  if (elf_flags & EF_FRV_FDPIC)
+    return GDB_OSABI_LINUX;
+  else
+    return GDB_OSABI_UNKNOWN;
+}
+
+/* Provide a prototype to silence -Wmissing-prototypes.  */
+void _initialize_frv_linux_tdep (void);
+
+void
+_initialize_frv_linux_tdep (void)
+{
+  gdbarch_register_osabi (bfd_arch_frv, 0, GDB_OSABI_LINUX, frv_linux_init_abi);
+  gdbarch_register_osabi_sniffer (bfd_arch_frv,
+				  bfd_target_elf_flavour,
+				  frv_linux_elf_osabi_sniffer);
+}