* Makefile.in (mips_linux_tdep_h): New.

	(mpis-linux-nat.o, mips-linux-tdep.o): Update.
	* mips-linux-nat.c: Include "inferior.h", "mips-linux-tdep.h", and
	<sys/ptrace.h>.
	(have_ptrace_regsets, super_fetch_registers, super_store_registers)
	(mips64_linux_regsets_fetch_registers)
	(mips64_linux_regsets_store_registers, mips64_linux_fetch_registers)
	(mips64_linux_store_registers): New.
	(_initialize_mips_linux_nat): Override to_fetch_registers and
	to_store_registers.
	* mips-linux-tdep.h: New file.
	* mips-linux-tdep.c: Include "mips-linux-tdep.c".
	(ELF_NGREG, ELF_NFPREG, elf_greg_t, elf_gregset_t, elf_fpreg_t)
	(elf_fpregset_t, FPR_BASE, PC, CAUSE, BADVADDR, MMHI, MMLO)
	(FPC_CSR, FPC_EIR, EF_REG0, EF_REG31, EF_LO, EF_HI, EF_CP0_EPC)
	(EF_CP0_BADVADDR, EF_CP0_STATUS, EF_CP0_CAUSE, EF_SIZE)
	(MIPS64_ELF_NGREG, MIPS64_ELF_NFPREG, mips64_elf_greg_t)
	(mips64_elf_gregset_t, mips64_elf_fpreg_t, mips64_elf_fpregset_t)
	(MIPS64_FPR_BASE, MIPS64_PC, MIPS64_CAUSE, MIPS64_BADVADDR)
	(MIPS64_MMHI, MIPS64_MMLO, MIPS64_FPC_CSR, MIPS64_FPC_EIR)
	(MIPS64_EF_REG0, MIPS64_EF_REG31, MIPS64_EF_LO, MIPS64_EF_HI)
	(MIPS64_EF_CP0_EPC, MIPS64_EF_CP0_BADVADDR, MIPS64_EF_CP0_STATUS)
	(MIPS64_EF_CP0_CAUSE, MIPS64_EF_SIZE): Delete.
	(supply_32bit_reg): Use gdb_byte.
	(supply_64bit_reg): New.
	(mips_supply_gregset, mips_fill_gregset, mips_supply_fpregset)
	(mips_fill_fpregset, fetch_core_registers, supply_gregset)
	(fill_gregset, supply_fpregset): Update for renamed types.
	(mips64_supply_gregset): Use gdb_byte and supply_64bit_reg.
	(mips64_fill_gregset): Make global.  Handle 32-bit register
	sizes.
	(mips64_fill_fpregset): Make global.  Use gdb_byte.  Handle
	FP regsets properly.

5 files changed, 429 insertions, 141 deletions

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 622c0839496..5b76385a6e7 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,5 +1,41 @@
 2006-03-15  Daniel Jacobowitz  <dan@codesourcery.com>
 
+	* Makefile.in (mips_linux_tdep_h): New.
+	(mpis-linux-nat.o, mips-linux-tdep.o): Update.
+	* mips-linux-nat.c: Include "inferior.h", "mips-linux-tdep.h", and
+	<sys/ptrace.h>.
+	(have_ptrace_regsets, super_fetch_registers, super_store_registers)
+	(mips64_linux_regsets_fetch_registers)
+	(mips64_linux_regsets_store_registers, mips64_linux_fetch_registers)
+	(mips64_linux_store_registers): New.
+	(_initialize_mips_linux_nat): Override to_fetch_registers and
+	to_store_registers.
+	* mips-linux-tdep.h: New file.
+	* mips-linux-tdep.c: Include "mips-linux-tdep.c".
+	(ELF_NGREG, ELF_NFPREG, elf_greg_t, elf_gregset_t, elf_fpreg_t)
+	(elf_fpregset_t, FPR_BASE, PC, CAUSE, BADVADDR, MMHI, MMLO)
+	(FPC_CSR, FPC_EIR, EF_REG0, EF_REG31, EF_LO, EF_HI, EF_CP0_EPC)
+	(EF_CP0_BADVADDR, EF_CP0_STATUS, EF_CP0_CAUSE, EF_SIZE)
+	(MIPS64_ELF_NGREG, MIPS64_ELF_NFPREG, mips64_elf_greg_t)
+	(mips64_elf_gregset_t, mips64_elf_fpreg_t, mips64_elf_fpregset_t)
+	(MIPS64_FPR_BASE, MIPS64_PC, MIPS64_CAUSE, MIPS64_BADVADDR)
+	(MIPS64_MMHI, MIPS64_MMLO, MIPS64_FPC_CSR, MIPS64_FPC_EIR)
+	(MIPS64_EF_REG0, MIPS64_EF_REG31, MIPS64_EF_LO, MIPS64_EF_HI)
+	(MIPS64_EF_CP0_EPC, MIPS64_EF_CP0_BADVADDR, MIPS64_EF_CP0_STATUS)
+	(MIPS64_EF_CP0_CAUSE, MIPS64_EF_SIZE): Delete.
+	(supply_32bit_reg): Use gdb_byte.
+	(supply_64bit_reg): New.
+	(mips_supply_gregset, mips_fill_gregset, mips_supply_fpregset)
+	(mips_fill_fpregset, fetch_core_registers, supply_gregset)
+	(fill_gregset, supply_fpregset): Update for renamed types.
+	(mips64_supply_gregset): Use gdb_byte and supply_64bit_reg.
+	(mips64_fill_gregset): Make global.  Handle 32-bit register
+	sizes.
+	(mips64_fill_fpregset): Make global.  Use gdb_byte.  Handle
+	FP regsets properly.
+
+2006-03-15  Daniel Jacobowitz  <dan@codesourcery.com>
+
 	* mips-linux-tdep.c (mips_supply_gregset): Renamed from supply_gregset.
 	(mips_fill_gregset): Renamed from fill_gregset.
 	(mips_supply_fpregset): Renamed from supply_fpregset.
diff --git a/gdb/Makefile.in b/gdb/Makefile.in
index 45139fb3a70..04ceed354f2 100644
--- a/gdb/Makefile.in
+++ b/gdb/Makefile.in
@@ -737,6 +737,7 @@ macrotab_h = macrotab.h
 main_h = main.h
 mdebugread_h = mdebugread.h $(coff_sym_h) $(coff_symconst_h)
 memattr_h = memattr.h
+mips_linux_tdep_h = mips-linux-tdep.h
 mips_mdebug_tdep_h = mips-mdebug-tdep.h
 mipsnbsd_tdep_h = mipsnbsd-tdep.h
 mips_tdep_h = mips-tdep.h
@@ -2295,11 +2296,12 @@ mips64obsd-tdep.o: mips64obsd-tdep.c $(defs_h) $(osabi_h) $(regcache_h) \
 	$(gdb_string_h) $(mips_tdep_h) $(solib_svr4_h)
 mips-irix-tdep.o: mips-irix-tdep.c $(defs_h) $(osabi_h) $(elf_bfd_h)
 mips-linux-nat.o: mips-linux-nat.c $(defs_h) $(mips_tdep_h) $(target_h) \
-	$(linux_nat_h) $(gdb_proc_service_h)
+	$(linux_nat_h) $(gdb_proc_service_h) $(mips_linux_tdep_h) \
+	$(inferior_h)
 mips-linux-tdep.o: mips-linux-tdep.c $(defs_h) $(gdbcore_h) $(target_h) \
 	$(solib_svr4_h) $(osabi_h) $(mips_tdep_h) $(gdb_string_h) \
 	$(gdb_assert_h) $(frame_h) $(regcache_h) $(trad_frame_h) \
-	$(tramp_frame_h) $(floatformat_h)
+	$(tramp_frame_h) $(floatformat_h) $(mips_linux_tdep_h)
 mips-mdebug-tdep.o: mips-mdebug-tdep.c $(defs_h) $(frame_h) $(mips_tdep_h) \
 	$(trad_frame_h) $(block_h) $(symtab_h) $(objfiles_h) $(elf_mips_h) \
 	$(elf_bfd_h) $(gdb_assert_h) $(frame_unwind_h) $(frame_base_h) \
diff --git a/gdb/mips-linux-nat.c b/gdb/mips-linux-nat.c
index 1f18771c9b3..985ff2781d3 100644
--- a/gdb/mips-linux-nat.c
+++ b/gdb/mips-linux-nat.c
@@ -21,16 +21,30 @@
    Boston, MA 02110-1301, USA.  */
 
 #include "defs.h"
+#include "inferior.h"
 #include "mips-tdep.h"
 #include "target.h"
 #include "linux-nat.h"
+#include "mips-linux-tdep.h"
 
 #include "gdb_proc_service.h"
 
+#include <sys/ptrace.h>
+
 #ifndef PTRACE_GET_THREAD_AREA
 #define PTRACE_GET_THREAD_AREA 25
 #endif
 
+/* Assume that we have PTRACE_GETREGS et al. support.  If we do not,
+   we'll clear this and use PTRACE_PEEKUSER instead.  */
+static int have_ptrace_regsets = 1;
+
+/* Saved function pointers to fetch and store a single register using
+   PTRACE_PEEKUSER and PTRACE_POKEUSER.  */
+
+void (*super_fetch_registers) (int);
+void (*super_store_registers) (int);
+
 /* Pseudo registers can not be read.  ptrace does not provide a way to
    read (or set) MIPS_PS_REGNUM, and there's no point in reading or
    setting MIPS_ZERO_REGNUM.  We also can not set BADVADDR, CAUSE, or
@@ -89,10 +103,161 @@ ps_get_thread_area (const struct ps_prochandle *ph,
   return PS_OK;
 }
 
+/* Fetch REGNO (or all registers if REGNO == -1) from the target
+   using PTRACE_GETREGS et al.  */
+
+static void
+mips64_linux_regsets_fetch_registers (int regno)
+{
+  int is_fp;
+  int tid;
+
+  if (regno >= mips_regnum (current_gdbarch)->fp0
+      && regno <= mips_regnum (current_gdbarch)->fp0 + 32)
+    is_fp = 1;
+  else if (regno == mips_regnum (current_gdbarch)->fp_control_status)
+    is_fp = 1;
+  else if (regno == mips_regnum (current_gdbarch)->fp_implementation_revision)
+    is_fp = 1;
+  else
+    is_fp = 0;
+
+  tid = ptid_get_lwp (inferior_ptid);
+  if (tid == 0)
+    tid = ptid_get_pid (inferior_ptid);
+
+  if (regno == -1 || !is_fp)
+    {
+      mips64_elf_gregset_t regs;
+
+      if (ptrace (PTRACE_GETREGS, tid, 0L, (PTRACE_TYPE_ARG3) &regs) == -1)
+	{
+	  if (errno == EIO)
+	    {
+	      have_ptrace_regsets = 0;
+	      return;
+	    }
+	  perror_with_name (_("Couldn't get registers"));
+	}
+
+      mips64_supply_gregset (&regs);
+    }
+
+  if (regno == -1 || is_fp)
+    {
+      mips64_elf_fpregset_t fp_regs;
+
+      if (ptrace (PTRACE_GETFPREGS, tid, 0L,
+		  (PTRACE_TYPE_ARG3) &fp_regs) == -1)
+	{
+	  if (errno == EIO)
+	    {
+	      have_ptrace_regsets = 0;
+	      return;
+	    }
+	  perror_with_name (_("Couldn't get FP registers"));
+	}
+
+      mips64_supply_fpregset (&fp_regs);
+    }
+}
+
+/* Store REGNO (or all registers if REGNO == -1) to the target
+   using PTRACE_SETREGS et al.  */
+
+static void
+mips64_linux_regsets_store_registers (int regno)
+{
+  int is_fp;
+  int tid;
+
+  if (regno >= mips_regnum (current_gdbarch)->fp0
+      && regno <= mips_regnum (current_gdbarch)->fp0 + 32)
+    is_fp = 1;
+  else if (regno == mips_regnum (current_gdbarch)->fp_control_status)
+    is_fp = 1;
+  else if (regno == mips_regnum (current_gdbarch)->fp_implementation_revision)
+    is_fp = 1;
+  else
+    is_fp = 0;
+
+  tid = ptid_get_lwp (inferior_ptid);
+  if (tid == 0)
+    tid = ptid_get_pid (inferior_ptid);
+
+  if (regno == -1 || !is_fp)
+    {
+      mips64_elf_gregset_t regs;
+
+      if (ptrace (PTRACE_GETREGS, tid, 0L, (PTRACE_TYPE_ARG3) &regs) == -1)
+	perror_with_name (_("Couldn't get registers"));
+
+      mips64_fill_gregset (&regs, regno);
+
+      if (ptrace (PTRACE_SETREGS, tid, 0L, (PTRACE_TYPE_ARG3) &regs) == -1)
+	perror_with_name (_("Couldn't set registers"));
+    }
+
+  if (regno == -1 || is_fp)
+    {
+      mips64_elf_fpregset_t fp_regs;
+
+      if (ptrace (PTRACE_GETFPREGS, tid, 0L,
+		  (PTRACE_TYPE_ARG3) &fp_regs) == -1)
+	perror_with_name (_("Couldn't get FP registers"));
+
+      mips64_fill_fpregset (&fp_regs, regno);
+
+      if (ptrace (PTRACE_SETFPREGS, tid, 0L,
+		  (PTRACE_TYPE_ARG3) &fp_regs) == -1)
+	perror_with_name (_("Couldn't set FP registers"));
+    }
+}
+
+/* Fetch REGNO (or all registers if REGNO == -1) from the target
+   using any working method.  */
+
+static void
+mips64_linux_fetch_registers (int regnum)
+{
+  /* Unless we already know that PTRACE_GETREGS does not work, try it.  */
+  if (have_ptrace_regsets)
+    mips64_linux_regsets_fetch_registers (regnum);
+
+  /* If we know, or just found out, that PTRACE_GETREGS does not work, fall
+     back to PTRACE_PEEKUSER.  */
+  if (!have_ptrace_regsets)
+    super_fetch_registers (regnum);
+}
+
+/* Store REGNO (or all registers if REGNO == -1) to the target
+   using any working method.  */
+
+static void
+mips64_linux_store_registers (int regnum)
+{
+  /* Unless we already know that PTRACE_GETREGS does not work, try it.  */
+  if (have_ptrace_regsets)
+    mips64_linux_regsets_store_registers (regnum);
+
+  /* If we know, or just found out, that PTRACE_GETREGS does not work, fall
+     back to PTRACE_PEEKUSER.  */
+  if (!have_ptrace_regsets)
+    super_store_registers (regnum);
+}
+
 void _initialize_mips_linux_nat (void);
 
 void
 _initialize_mips_linux_nat (void)
 {
-  add_target (linux_target ());
+  struct target_ops *t = linux_target ();
+
+  super_fetch_registers = t->to_fetch_registers;
+  super_store_registers = t->to_store_registers;
+
+  t->to_fetch_registers = mips64_linux_fetch_registers;
+  t->to_store_registers = mips64_linux_store_registers;
+
+  add_target (t);
 }
diff --git a/gdb/mips-linux-tdep.c b/gdb/mips-linux-tdep.c
index 1aaeeb62288..5d789d24577 100644
--- a/gdb/mips-linux-tdep.c
+++ b/gdb/mips-linux-tdep.c
@@ -33,37 +33,7 @@
 #include "trad-frame.h"
 #include "tramp-frame.h"
 #include "floatformat.h"
-
-/* Copied from <asm/elf.h>.  */
-#define ELF_NGREG       45
-#define ELF_NFPREG      33
-
-typedef unsigned char elf_greg_t[4];
-typedef elf_greg_t elf_gregset_t[ELF_NGREG];
-
-typedef unsigned char elf_fpreg_t[8];
-typedef elf_fpreg_t elf_fpregset_t[ELF_NFPREG];
-
-/* 0 - 31 are integer registers, 32 - 63 are fp registers.  */
-#define FPR_BASE        32
-#define PC              64
-#define CAUSE           65
-#define BADVADDR        66
-#define MMHI            67
-#define MMLO            68
-#define FPC_CSR         69
-#define FPC_EIR         70
-
-#define EF_REG0			6
-#define EF_REG31		37
-#define EF_LO			38
-#define EF_HI			39
-#define EF_CP0_EPC		40
-#define EF_CP0_BADVADDR		41
-#define EF_CP0_STATUS		42
-#define EF_CP0_CAUSE		43
-
-#define EF_SIZE			180
+#include "mips-linux-tdep.h"
 
 /* Figure out where the longjmp will land.
    We expect the first arg to be a pointer to the jmp_buf structure
@@ -99,7 +69,7 @@ mips_linux_get_longjmp_target (CORE_ADDR *pc)
 static void
 supply_32bit_reg (int regnum, const void *addr)
 {
-  char buf[MAX_REGISTER_SIZE];
+  gdb_byte buf[MAX_REGISTER_SIZE];
   store_signed_integer (buf, register_size (current_gdbarch, regnum),
                         extract_signed_integer (addr, 4));
   regcache_raw_supply (current_regcache, regnum, buf);
@@ -107,11 +77,11 @@ supply_32bit_reg (int regnum, const void *addr)
 
 /* Unpack an elf_gregset_t into GDB's register cache.  */
 
-static void
-mips_supply_gregset (elf_gregset_t *gregsetp)
+void
+mips_supply_gregset (mips_elf_gregset_t *gregsetp)
 {
   int regi;
-  elf_greg_t *regp = *gregsetp;
+  mips_elf_greg_t *regp = *gregsetp;
   char zerobuf[MAX_REGISTER_SIZE];
 
   memset (zerobuf, 0, MAX_REGISTER_SIZE);
@@ -142,16 +112,16 @@ mips_supply_gregset (elf_gregset_t *gregsetp)
 
 /* Pack our registers (or one register) into an elf_gregset_t.  */
 
-static void
-mips_fill_gregset (elf_gregset_t *gregsetp, int regno)
+void
+mips_fill_gregset (mips_elf_gregset_t *gregsetp, int regno)
 {
   int regaddr, regi;
-  elf_greg_t *regp = *gregsetp;
+  mips_elf_greg_t *regp = *gregsetp;
   void *dst;
 
   if (regno == -1)
     {
-      memset (regp, 0, sizeof (elf_gregset_t));
+      memset (regp, 0, sizeof (mips_elf_gregset_t));
       for (regi = 0; regi < 32; regi++)
 	mips_fill_gregset (gregsetp, regi);
       mips_fill_gregset (gregsetp, mips_regnum (current_gdbarch)->lo);
@@ -195,8 +165,8 @@ mips_fill_gregset (elf_gregset_t *gregsetp, int regno)
 
 /* Likewise, unpack an elf_fpregset_t.  */
 
-static void
-mips_supply_fpregset (elf_fpregset_t *fpregsetp)
+void
+mips_supply_fpregset (mips_elf_fpregset_t *fpregsetp)
 {
   int regi;
   char zerobuf[MAX_REGISTER_SIZE];
@@ -220,8 +190,8 @@ mips_supply_fpregset (elf_fpregset_t *fpregsetp)
 /* Likewise, pack one or all floating point registers into an
    elf_fpregset_t.  */
 
-static void
-mips_fill_fpregset (elf_fpregset_t *fpregsetp, int regno)
+void
+mips_fill_fpregset (mips_elf_fpregset_t *fpregsetp, int regno)
 {
   char *from, *to;
 
@@ -284,37 +254,6 @@ mips_linux_register_addr (int regno, CORE_ADDR blockend)
 
 /* Support for 64-bit ABIs.  */
 
-/* Copied from <asm/elf.h>.  */
-#define MIPS64_ELF_NGREG       45
-#define MIPS64_ELF_NFPREG      33
-
-typedef unsigned char mips64_elf_greg_t[8];
-typedef mips64_elf_greg_t mips64_elf_gregset_t[MIPS64_ELF_NGREG];
-
-typedef unsigned char mips64_elf_fpreg_t[8];
-typedef mips64_elf_fpreg_t mips64_elf_fpregset_t[MIPS64_ELF_NFPREG];
-
-/* 0 - 31 are integer registers, 32 - 63 are fp registers.  */
-#define MIPS64_FPR_BASE                 32
-#define MIPS64_PC                       64
-#define MIPS64_CAUSE                    65
-#define MIPS64_BADVADDR                 66
-#define MIPS64_MMHI                     67
-#define MIPS64_MMLO                     68
-#define MIPS64_FPC_CSR                  69
-#define MIPS64_FPC_EIR                  70
-
-#define MIPS64_EF_REG0			 0
-#define MIPS64_EF_REG31			31
-#define MIPS64_EF_LO			32
-#define MIPS64_EF_HI			33
-#define MIPS64_EF_CP0_EPC		34
-#define MIPS64_EF_CP0_BADVADDR		35
-#define MIPS64_EF_CP0_STATUS		36
-#define MIPS64_EF_CP0_CAUSE		37
-
-#define MIPS64_EF_SIZE			304
-
 /* Figure out where the longjmp will land.
    We expect the first arg to be a pointer to the jmp_buf structure
    from which we extract the pc (MIPS_LINUX_JB_PC) that we will land
@@ -343,39 +282,49 @@ mips64_linux_get_longjmp_target (CORE_ADDR *pc)
   return 1;
 }
 
-/* Unpack an elf_gregset_t into GDB's register cache.  */
+/* Register set support functions.  These operate on standard 64-bit
+   regsets, but work whether the target is 32-bit or 64-bit.  A 32-bit
+   target will still use the 64-bit format for PTRACE_GETREGS.  */
+
+/* Supply a 64-bit register.  */
 
-static void 
+void
+supply_64bit_reg (int regnum, const gdb_byte *buf)
+{
+  if (gdbarch_byte_order (current_gdbarch) == BFD_ENDIAN_BIG
+      && register_size (current_gdbarch, regnum) == 4)
+    regcache_raw_supply (current_regcache, regnum, buf + 4);
+  else
+    regcache_raw_supply (current_regcache, regnum, buf);
+}
+
+/* Unpack a 64-bit elf_gregset_t into GDB's register cache.  */
+
+void
 mips64_supply_gregset (mips64_elf_gregset_t *gregsetp)
 {
   int regi;
   mips64_elf_greg_t *regp = *gregsetp;
-  char zerobuf[MAX_REGISTER_SIZE];
+  gdb_byte zerobuf[MAX_REGISTER_SIZE];
 
   memset (zerobuf, 0, MAX_REGISTER_SIZE);
 
   for (regi = MIPS64_EF_REG0; regi <= MIPS64_EF_REG31; regi++)
-    regcache_raw_supply (current_regcache, (regi - MIPS64_EF_REG0),
-			 (char *)(regp + regi));
-
-  regcache_raw_supply (current_regcache,
-		       mips_regnum (current_gdbarch)->lo,
-		       (char *) (regp + MIPS64_EF_LO));
-  regcache_raw_supply (current_regcache,
-		       mips_regnum (current_gdbarch)->hi,
-		       (char *) (regp + MIPS64_EF_HI));
-
-  regcache_raw_supply (current_regcache,
-		       mips_regnum (current_gdbarch)->pc,
-		       (char *) (regp + MIPS64_EF_CP0_EPC));
-  regcache_raw_supply (current_regcache,
-		       mips_regnum (current_gdbarch)->badvaddr,
-		       (char *) (regp + MIPS64_EF_CP0_BADVADDR));
-  regcache_raw_supply (current_regcache, MIPS_PS_REGNUM,
-		       (char *) (regp + MIPS64_EF_CP0_STATUS));
-  regcache_raw_supply (current_regcache,
-		       mips_regnum (current_gdbarch)->cause,
-		       (char *) (regp + MIPS64_EF_CP0_CAUSE));
+    supply_64bit_reg (regi - MIPS64_EF_REG0, (gdb_byte *)(regp + regi));
+
+  supply_64bit_reg (mips_regnum (current_gdbarch)->lo,
+		    (gdb_byte *) (regp + MIPS64_EF_LO));
+  supply_64bit_reg (mips_regnum (current_gdbarch)->hi,
+		    (gdb_byte *) (regp + MIPS64_EF_HI));
+
+  supply_64bit_reg (mips_regnum (current_gdbarch)->pc,
+		    (gdb_byte *) (regp + MIPS64_EF_CP0_EPC));
+  supply_64bit_reg (mips_regnum (current_gdbarch)->badvaddr,
+		    (gdb_byte *) (regp + MIPS64_EF_CP0_BADVADDR));
+  supply_64bit_reg (MIPS_PS_REGNUM,
+		    (gdb_byte *) (regp + MIPS64_EF_CP0_STATUS));
+  supply_64bit_reg (mips_regnum (current_gdbarch)->cause,
+		    (gdb_byte *) (regp + MIPS64_EF_CP0_CAUSE));
 
   /* Fill inaccessible registers with zero.  */
   regcache_raw_supply (current_regcache, MIPS_UNUSED_REGNUM, zerobuf);
@@ -385,9 +334,9 @@ mips64_supply_gregset (mips64_elf_gregset_t *gregsetp)
     regcache_raw_supply (current_regcache, regi, zerobuf);
 }
 
-/* Pack our registers (or one register) into an elf_gregset_t.  */
+/* Pack our registers (or one register) into a 64-bit elf_gregset_t.  */
 
-static void
+void
 mips64_fill_gregset (mips64_elf_gregset_t *gregsetp, int regno)
 {
   int regaddr, regi;
@@ -412,13 +361,8 @@ mips64_fill_gregset (mips64_elf_gregset_t *gregsetp, int regno)
    }
 
   if (regno < 32)
-    {
-      dst = regp + regno + MIPS64_EF_REG0;
-      regcache_raw_collect (current_regcache, regno, dst);
-      return;
-    }
-
-  if (regno == mips_regnum (current_gdbarch)->lo)
+    regaddr = regno + MIPS64_EF_REG0;
+  else if (regno == mips_regnum (current_gdbarch)->lo)
     regaddr = MIPS64_EF_LO;
   else if (regno == mips_regnum (current_gdbarch)->hi)
     regaddr = MIPS64_EF_HI;
@@ -435,52 +379,97 @@ mips64_fill_gregset (mips64_elf_gregset_t *gregsetp, int regno)
 
   if (regaddr != -1)
     {
+      gdb_byte buf[MAX_REGISTER_SIZE];
+      LONGEST val;
+
+      regcache_raw_collect (current_regcache, regno, buf);
+      val = extract_signed_integer (buf,
+				    register_size (current_gdbarch, regno));
       dst = regp + regaddr;
-      regcache_raw_collect (current_regcache, regno, dst);
+      store_signed_integer (dst, 8, val);
     }
 }
 
 /* Likewise, unpack an elf_fpregset_t.  */
 
-static void
+void
 mips64_supply_fpregset (mips64_elf_fpregset_t *fpregsetp)
 {
   int regi;
-  char zerobuf[MAX_REGISTER_SIZE];
-
-  memset (zerobuf, 0, MAX_REGISTER_SIZE);
-
-  for (regi = 0; regi < 32; regi++)
-    regcache_raw_supply (current_regcache, FP0_REGNUM + regi,
-			 (char *)(*fpregsetp + regi));
 
-  regcache_raw_supply (current_regcache,
-		       mips_regnum (current_gdbarch)->fp_control_status,
-		       (char *)(*fpregsetp + 32));
-
-  /* FIXME: how can we supply FCRIR?  The ABI doesn't tell us.  */
-  regcache_raw_supply (current_regcache,
-		       mips_regnum (current_gdbarch)->fp_implementation_revision,
-		       zerobuf);
+  /* See mips_linux_o32_sigframe_init for a description of the
+     peculiar FP register layout.  */
+  if (register_size (current_gdbarch, FP0_REGNUM) == 4)
+    for (regi = 0; regi < 32; regi++)
+      {
+	gdb_byte *reg_ptr = (gdb_byte *) (*fpregsetp + (regi & ~1));
+	if ((TARGET_BYTE_ORDER == BFD_ENDIAN_BIG) != (regi & 1))
+	  reg_ptr += 4;
+	regcache_raw_supply (current_regcache, FP0_REGNUM + regi, reg_ptr);
+      }
+  else
+    for (regi = 0; regi < 32; regi++)
+      regcache_raw_supply (current_regcache, FP0_REGNUM + regi,
+			   (char *)(*fpregsetp + regi));
+
+  supply_32bit_reg (mips_regnum (current_gdbarch)->fp_control_status,
+		    (gdb_byte *)(*fpregsetp + 32));
+
+  /* The ABI doesn't tell us how to supply FCRIR, and core dumps don't
+     include it - but the result of PTRACE_GETFPREGS does.  The best we
+     can do is to assume that its value is present.  */
+  supply_32bit_reg (mips_regnum (current_gdbarch)->fp_implementation_revision,
+		    (gdb_byte *)(*fpregsetp + 32) + 4);
 }
 
 /* Likewise, pack one or all floating point registers into an
    elf_fpregset_t.  */
 
-static void
+void
 mips64_fill_fpregset (mips64_elf_fpregset_t *fpregsetp, int regno)
 {
-  char *from, *to;
+  gdb_byte *to;
 
   if ((regno >= FP0_REGNUM) && (regno < FP0_REGNUM + 32))
     {
-      to = (char *) (*fpregsetp + regno - FP0_REGNUM);
-      regcache_raw_collect (current_regcache, regno, to);
+      /* See mips_linux_o32_sigframe_init for a description of the
+	 peculiar FP register layout.  */
+      if (register_size (current_gdbarch, regno) == 4)
+	{
+	  int regi = regno - FP0_REGNUM;
+
+	  to = (gdb_byte *) (*fpregsetp + (regi & ~1));
+	  if ((TARGET_BYTE_ORDER == BFD_ENDIAN_BIG) != (regi & 1))
+	    to += 4;
+	  regcache_raw_collect (current_regcache, regno, to);
+	}
+      else
+	{
+	  to = (gdb_byte *) (*fpregsetp + regno - FP0_REGNUM);
+	  regcache_raw_collect (current_regcache, regno, to);
+	}
     }
   else if (regno == mips_regnum (current_gdbarch)->fp_control_status)
     {
-      to = (char *) (*fpregsetp + 32);
-      regcache_raw_collect (current_regcache, regno, to);
+      gdb_byte buf[MAX_REGISTER_SIZE];
+      LONGEST val;
+
+      regcache_raw_collect (current_regcache, regno, buf);
+      val = extract_signed_integer (buf,
+				    register_size (current_gdbarch, regno));
+      to = (gdb_byte *) (*fpregsetp + 32);
+      store_signed_integer (to, 4, val);
+    }
+  else if (regno == mips_regnum (current_gdbarch)->fp_implementation_revision)
+    {
+      gdb_byte buf[MAX_REGISTER_SIZE];
+      LONGEST val;
+
+      regcache_raw_collect (current_regcache, regno, buf);
+      val = extract_signed_integer (buf,
+				    register_size (current_gdbarch, regno));
+      to = (gdb_byte *) (*fpregsetp + 32) + 4;
+      store_signed_integer (to, 4, val);
     }
   else if (regno == -1)
     {
@@ -488,8 +477,10 @@ mips64_fill_fpregset (mips64_elf_fpregset_t *fpregsetp, int regno)
 
       for (regi = 0; regi < 32; regi++)
 	mips64_fill_fpregset (fpregsetp, FP0_REGNUM + regi);
-      mips64_fill_fpregset(fpregsetp,
-			   mips_regnum (current_gdbarch)->fp_control_status);
+      mips64_fill_fpregset (fpregsetp,
+			    mips_regnum (current_gdbarch)->fp_control_status);
+      mips64_fill_fpregset (fpregsetp, (mips_regnum (current_gdbarch)
+					->fp_implementation_revision));
     }
 }
 
@@ -537,8 +528,8 @@ static void
 fetch_core_registers (char *core_reg_sect, unsigned core_reg_size,
 		      int which, CORE_ADDR reg_addr)
 {
-  elf_gregset_t gregset;
-  elf_fpregset_t fpregset;
+  mips_elf_gregset_t gregset;
+  mips_elf_fpregset_t fpregset;
   mips64_elf_gregset_t gregset64;
   mips64_elf_fpregset_t fpregset64;
 
@@ -1088,7 +1079,7 @@ mips_linux_n32n64_sigframe_init (const struct tramp_frame *self,
 /* Wrapper functions.  These are only used by libthread_db.  */
 
 void
-supply_gregset (elf_gregset_t *gregsetp)
+supply_gregset (mips_elf_gregset_t *gregsetp)
 {
   if (mips_isa_regsize (current_gdbarch) == 4)
     mips_supply_gregset (gregsetp);
@@ -1097,7 +1088,7 @@ supply_gregset (elf_gregset_t *gregsetp)
 }
 
 void
-fill_gregset (elf_gregset_t *gregsetp, int regno)
+fill_gregset (mips_elf_gregset_t *gregsetp, int regno)
 {
   if (mips_isa_regsize (current_gdbarch) == 4)
     mips_fill_gregset (gregsetp, regno);
@@ -1108,7 +1099,7 @@ fill_gregset (elf_gregset_t *gregsetp, int regno)
 /* Likewise, unpack an elf_fpregset_t.  */
 
 void
-supply_fpregset (elf_fpregset_t *fpregsetp)
+supply_fpregset (mips_elf_fpregset_t *fpregsetp)
 {
   if (mips_isa_regsize (current_gdbarch) == 4)
     mips_supply_fpregset (fpregsetp);
@@ -1120,7 +1111,7 @@ supply_fpregset (elf_fpregset_t *fpregsetp)
    elf_fpregset_t.  */
 
 void
-fill_fpregset (elf_fpregset_t *fpregsetp, int regno)
+fill_fpregset (mips_elf_fpregset_t *fpregsetp, int regno)
 {
   if (mips_isa_regsize (current_gdbarch) == 4)
     mips_fill_fpregset (fpregsetp, regno);
diff --git a/gdb/mips-linux-tdep.h b/gdb/mips-linux-tdep.h
new file mode 100644
index 00000000000..4914b638a23
--- /dev/null
+++ b/gdb/mips-linux-tdep.h
@@ -0,0 +1,94 @@
+/* Target-dependent code for GNU/Linux on MIPS processors.
+
+   Copyright 2006 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.  */
+
+/* Copied from <asm/elf.h>.  */
+#define ELF_NGREG       45
+#define ELF_NFPREG      33
+
+typedef unsigned char mips_elf_greg_t[4];
+typedef mips_elf_greg_t mips_elf_gregset_t[ELF_NGREG];
+
+typedef unsigned char mips_elf_fpreg_t[8];
+typedef mips_elf_fpreg_t mips_elf_fpregset_t[ELF_NFPREG];
+
+/* 0 - 31 are integer registers, 32 - 63 are fp registers.  */
+#define FPR_BASE        32
+#define PC              64
+#define CAUSE           65
+#define BADVADDR        66
+#define MMHI            67
+#define MMLO            68
+#define FPC_CSR         69
+#define FPC_EIR         70
+
+#define EF_REG0			6
+#define EF_REG31		37
+#define EF_LO			38
+#define EF_HI			39
+#define EF_CP0_EPC		40
+#define EF_CP0_BADVADDR		41
+#define EF_CP0_STATUS		42
+#define EF_CP0_CAUSE		43
+
+#define EF_SIZE			180
+
+void mips_supply_gregset (mips_elf_gregset_t *);
+void mips_fill_gregset (mips_elf_gregset_t *, int);
+void mips_supply_fpregset (mips_elf_fpregset_t *);
+void mips_fill_fpregset (mips_elf_fpregset_t *, int);
+
+/* 64-bit support.  */
+
+/* Copied from <asm/elf.h>.  */
+#define MIPS64_ELF_NGREG       45
+#define MIPS64_ELF_NFPREG      33
+
+typedef unsigned char mips64_elf_greg_t[8];
+typedef mips64_elf_greg_t mips64_elf_gregset_t[MIPS64_ELF_NGREG];
+
+typedef unsigned char mips64_elf_fpreg_t[8];
+typedef mips64_elf_fpreg_t mips64_elf_fpregset_t[MIPS64_ELF_NFPREG];
+
+/* 0 - 31 are integer registers, 32 - 63 are fp registers.  */
+#define MIPS64_FPR_BASE                 32
+#define MIPS64_PC                       64
+#define MIPS64_CAUSE                    65
+#define MIPS64_BADVADDR                 66
+#define MIPS64_MMHI                     67
+#define MIPS64_MMLO                     68
+#define MIPS64_FPC_CSR                  69
+#define MIPS64_FPC_EIR                  70
+
+#define MIPS64_EF_REG0			 0
+#define MIPS64_EF_REG31			31
+#define MIPS64_EF_LO			32
+#define MIPS64_EF_HI			33
+#define MIPS64_EF_CP0_EPC		34
+#define MIPS64_EF_CP0_BADVADDR		35
+#define MIPS64_EF_CP0_STATUS		36
+#define MIPS64_EF_CP0_CAUSE		37
+
+#define MIPS64_EF_SIZE			304
+
+void mips64_supply_gregset (mips64_elf_gregset_t *);
+void mips64_fill_gregset (mips64_elf_gregset_t *, int);
+void mips64_supply_fpregset (mips64_elf_fpregset_t *);
+void mips64_fill_fpregset (mips64_elf_fpregset_t *, int);