[2/3] Add FreeBSD/mips architecture.

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index a2a11e2..092ca9e 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,11 @@ 
+2016-11-23  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*.
+	* mips-fbsd-tdep.c: New file.
+	* mips-fbsd-tdep.h: New file.
+
 2016-11-23  Pedro Alves  <palves@redhat.com>
 
 	* Makefile.in (SFILES): Add common/run-time-clock.c.
diff --git a/gdb/Makefile.in b/gdb/Makefile.in
index 44a743e..d89a17f 100644
--- a/gdb/Makefile.in
+++ b/gdb/Makefile.in
@@ -817,6 +817,7 @@  ALL_TARGET_OBS = \
 	mep-tdep.o \
 	microblaze-linux-tdep.o \
 	microblaze-tdep.o \
+	mips-fbsd-tdep.o \
 	mips-linux-tdep.o \
 	mips-nbsd-tdep.o \
 	mips-sde-tdep.o \
@@ -2541,6 +2542,7 @@  ALLDEPFILES = \
 	microblaze-linux-tdep.c \
 	microblaze-tdep.c \
 	mingw-hdep.c \
+	mips-fbsd-tdep.c \
 	mips-linux-nat.c \
 	mips-linux-tdep.c \
 	mips-nbsd-nat.c \
diff --git a/gdb/configure.tgt b/gdb/configure.tgt
index 3a1ea6f..1a43604 100644
--- a/gdb/configure.tgt
+++ b/gdb/configure.tgt
@@ -369,6 +369,11 @@  mips*-*-netbsd* | mips*-*-knetbsd*-gnu)
 	gdb_target_obs="mips-tdep.o mips-nbsd-tdep.o solib-svr4.o nbsd-tdep.o"
 	gdb_sim=../sim/mips/libsim.a
 	;;
+mips*-*-freebsd*)
+	# Target: MIPS running FreeBSD
+	gdb_target_obs="mips-tdep.o mips-fbsd-tdep.o solib-svr4.o fbsd-tdep.o"
+	gdb_sim=../sim/mips/libsim.a
+	;;
 mips64*-*-openbsd*)
 	# Target: OpenBSD/mips64
 	gdb_target_obs="mips-tdep.o mips64-obsd-tdep.o obsd-tdep.o solib-svr4.o"
diff --git a/gdb/mips-fbsd-tdep.c b/gdb/mips-fbsd-tdep.c
new file mode 100644
index 0000000..424eb95
--- /dev/null
+++ b/gdb/mips-fbsd-tdep.c
@@ -0,0 +1,541 @@ 
+/* Target-dependent code for FreeBSD/mips.
+
+   Copyright (C) 2016 Free Software Foundation, Inc.
+
+   This software was developed by SRI International and the University
+   of Cambridge Computer Laboratory under DARPA/AFRL contract
+   FA8750-10-C-0237 ("CTSRD"), as part of the DARPA CRASH research
+   programme.
+
+   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 3 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, see <http://www.gnu.org/licenses/>.  */
+
+#include "defs.h"
+#include "osabi.h"
+#include "regset.h"
+#include "trad-frame.h"
+#include "tramp-frame.h"
+
+#include "fbsd-tdep.h"
+#include "mips-tdep.h"
+#include "mips-fbsd-tdep.h"
+
+#include "solib-svr4.h"
+
+/* Shorthand for some register numbers used below.  */
+#define MIPS_PC_REGNUM  MIPS_EMBED_PC_REGNUM
+#define MIPS_FP0_REGNUM MIPS_EMBED_FP0_REGNUM
+#define MIPS_FSR_REGNUM MIPS_EMBED_FP0_REGNUM + 32
+
+/* Core file support. */
+
+/* Number of registers in `struct reg' from <machine/reg.h>.  The
+   first 38 follow the standard MIPS layout.  The 39th holds
+   IC_INT_REG on RM7K and RM9K processors.  The 40th is a dummy for
+   padding.  */
+#define MIPSFBSD_NUM_GREGS	40
+
+/* Number of registers in `struct fpreg' from <machine/reg.h>.  The
+   first 32 hold floating point registers.  33 holds the FSR.  The
+   34th is a dummy for padding.  */
+#define MIPSFBSD_NUM_FPREGS	34
+
+/* Supply a single register.  If the source register size matches the
+   size the regcache expects, this can use regcache_raw_supply().  If
+   they are different, this copies the source register into a buffer
+   that can be passed to regcache_raw_supply().  */
+
+static void
+mipsfbsd_supply_reg (struct regcache *regcache, int regnum, const void *addr,
+		     size_t len)
+{
+  struct gdbarch *gdbarch = get_regcache_arch (regcache);
+
+  if (register_size (gdbarch, regnum) == len)
+    {
+      regcache_raw_supply (regcache, regnum, addr);
+    }
+  else
+    {
+      enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
+      gdb_byte buf[MAX_REGISTER_SIZE];
+      LONGEST val;
+
+      val = extract_signed_integer ((const gdb_byte *) addr, len, byte_order);
+      store_signed_integer (buf, register_size (gdbarch, regnum), byte_order,
+			    val);
+      regcache_raw_supply (regcache, regnum, buf);
+    }
+}
+
+/* Collect a single register.  If the destination register size
+   matches the size the regcache expects, this can use
+   regcache_raw_supply().  If they are different, this fetches the
+   register via regcache_raw_supply() into a buffer and then copies it
+   into the final destination.  */
+
+static void
+mipsfbsd_collect_reg (const struct regcache *regcache, int regnum, void *addr,
+		      size_t len)
+{
+  struct gdbarch *gdbarch = get_regcache_arch (regcache);
+
+  if (register_size (gdbarch, regnum) == len)
+    {
+      regcache_raw_collect (regcache, regnum, addr);
+    }
+  else
+    {
+      enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
+      gdb_byte buf[MAX_REGISTER_SIZE];
+      LONGEST val;
+
+      regcache_raw_collect (regcache, regnum, buf);
+      val = extract_signed_integer (buf, register_size (gdbarch, regnum),
+				    byte_order);
+      store_signed_integer ((gdb_byte *) addr, len, byte_order, val);
+    }
+}
+
+/* Supply the floating-point registers stored in FPREGS to REGCACHE.
+   Each floating-point register in FPREGS is REGSIZE bytes in
+   length.  */
+
+void
+mipsfbsd_supply_fpregs (struct regcache *regcache, int regnum,
+			const void *fpregs, size_t regsize)
+{
+  const char *regs = (const char *) fpregs;
+  int i;
+
+  for (i = MIPS_FP0_REGNUM; i <= MIPS_FSR_REGNUM; i++)
+    {
+      if (regnum == i || regnum == -1)
+	mipsfbsd_supply_reg (regcache, i,
+			     regs + (i - MIPS_FP0_REGNUM) * regsize, regsize);
+    }
+}
+
+/* Supply the general-purpose registers stored in GREGS to REGCACHE.
+   Each general-purpose register in GREGS is REGSIZE bytes in
+   length.  */
+
+void
+mipsfbsd_supply_gregs (struct regcache *regcache, int regnum,
+		       const void *gregs, size_t regsize)
+{
+  const char *regs = (const char *) gregs;
+  int i;
+
+  for (i = 0; i <= MIPS_PC_REGNUM; i++)
+    {
+      if (regnum == i || regnum == -1)
+	mipsfbsd_supply_reg (regcache, i, regs + i * regsize, regsize);
+    }
+}
+
+/* Collect the floating-point registers from REGCACHE and store them
+   in FPREGS.  Each floating-point register in FPREGS is REGSIZE bytes
+   in length.  */
+
+void
+mipsfbsd_collect_fpregs (const struct regcache *regcache, int regnum,
+			 void *fpregs, size_t regsize)
+{
+  char *regs = (char *) fpregs;
+  int i;
+
+  for (i = MIPS_FP0_REGNUM; i <= MIPS_FSR_REGNUM; i++)
+    {
+      if (regnum == i || regnum == -1)
+	mipsfbsd_collect_reg (regcache, i,
+			     regs + (i - MIPS_FP0_REGNUM) * regsize, regsize);
+    }
+}
+
+/* Collect the general-purpose registers from REGCACHE and store them
+   in GREGS.  Each general-purpose register in GREGS is REGSIZE bytes
+   in length.  */
+
+void
+mipsfbsd_collect_gregs (const struct regcache *regcache, int regnum,
+			void *gregs, size_t regsize)
+{
+  char *regs = (char *) gregs;
+  int i;
+
+  for (i = 0; i <= MIPS_PC_REGNUM; i++)
+    {
+      if (regnum == i || regnum == -1)
+	mipsfbsd_collect_reg (regcache, i, regs + i * regsize, regsize);
+    }
+}
+
+/* Supply register REGNUM from the buffer specified by FPREGS and LEN
+   in the floating-point register set REGSET to register cache
+   REGCACHE.  If REGNUM is -1, do this for all registers in REGSET.  */
+
+static void
+mipsfbsd_supply_fpregset (const struct regset *regset,
+			  struct regcache *regcache,
+			  int regnum, const void *fpregs, size_t len)
+{
+  size_t regsize = mips_abi_regsize (get_regcache_arch (regcache));
+
+  gdb_assert (len >= MIPSFBSD_NUM_FPREGS * regsize);
+
+  mipsfbsd_supply_fpregs (regcache, regnum, fpregs, regsize);
+}
+
+/* Collect register REGNUM from the register cache REGCACHE and store
+   it in the buffer specified by FPREGS and LEN in the floating-point
+   register set REGSET.  If REGNUM is -1, do this for all registers in
+   REGSET.  */
+
+static void
+mipsfbsd_collect_fpregset (const struct regset *regset,
+			   const struct regcache *regcache,
+			   int regnum, void *fpregs, size_t len)
+{
+  size_t regsize = mips_abi_regsize (get_regcache_arch (regcache));
+
+  gdb_assert (len >= MIPSFBSD_NUM_FPREGS * regsize);
+
+  mipsfbsd_collect_fpregs (regcache, regnum, fpregs, regsize);
+}
+
+/* Supply register REGNUM from the buffer specified by GREGS and LEN
+   in the general-purpose register set REGSET to register cache
+   REGCACHE.  If REGNUM is -1, do this for all registers in REGSET.  */
+
+static void
+mipsfbsd_supply_gregset (const struct regset *regset,
+			 struct regcache *regcache, int regnum,
+			 const void *gregs, size_t len)
+{
+  size_t regsize = mips_abi_regsize (get_regcache_arch (regcache));
+
+  gdb_assert (len >= MIPSFBSD_NUM_GREGS * regsize);
+
+  mipsfbsd_supply_gregs (regcache, regnum, gregs, regsize);
+}
+
+/* Collect register REGNUM from the register cache REGCACHE and store
+   it in the buffer specified by GREGS and LEN in the general-purpose
+   register set REGSET.  If REGNUM is -1, do this for all registers in
+   REGSET.  */
+
+static void
+mipsfbsd_collect_gregset (const struct regset *regset,
+			  const struct regcache *regcache,
+			  int regnum, void *gregs, size_t len)
+{
+  size_t regsize = mips_abi_regsize (get_regcache_arch (regcache));
+
+  gdb_assert (len >= MIPSFBSD_NUM_GREGS * regsize);
+
+  mipsfbsd_collect_gregs (regcache, regnum, gregs, regsize);
+}
+
+/* FreeBSD/mips register sets.  */
+
+static const struct regset mipsfbsd_gregset =
+{
+  NULL,
+  mipsfbsd_supply_gregset,
+  mipsfbsd_collect_gregset,
+};
+
+static const struct regset mipsfbsd_fpregset =
+{
+  NULL,
+  mipsfbsd_supply_fpregset,
+  mipsfbsd_collect_fpregset,
+};
+
+/* Iterate over core file register note sections.  */
+
+static void
+mipsfbsd_iterate_over_regset_sections (struct gdbarch *gdbarch,
+				       iterate_over_regset_sections_cb *cb,
+				       void *cb_data,
+				       const struct regcache *regcache)
+{
+  size_t regsize = mips_abi_regsize (gdbarch);
+
+  cb (".reg", MIPSFBSD_NUM_GREGS * regsize, &mipsfbsd_gregset,
+      NULL, cb_data);
+  cb (".reg2", MIPSFBSD_NUM_FPREGS * regsize, &mipsfbsd_fpregset,
+      NULL, cb_data);
+}
+
+/* Signal trampoline support.  */
+
+static void
+mipsfbsd_sigframe_init (const struct tramp_frame *self,
+			  struct frame_info *this_frame,
+			  struct trad_frame_cache *cache,
+			  CORE_ADDR func)
+{
+  struct gdbarch *gdbarch = get_frame_arch (this_frame);
+  enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
+  CORE_ADDR sp, ucontext_addr, addr;
+  int regnum;
+  gdb_byte buf[4];
+
+  /* We find the appropriate instance of `ucontext_t' at a
+     fixed offset in the signal frame.  */
+  sp = get_frame_register_signed (this_frame,
+				  MIPS_SP_REGNUM + gdbarch_num_regs (gdbarch));
+  ucontext_addr = sp + 16;
+
+  /* PC.  */
+  regnum = mips_regnum (gdbarch)->pc;
+  trad_frame_set_reg_addr (cache,
+			   regnum + gdbarch_num_regs (gdbarch),
+			    ucontext_addr + 20);
+
+  /* GPRs.  */
+  for (regnum = MIPS_AT_REGNUM, addr = ucontext_addr + 28;
+       regnum <= MIPS_RA_REGNUM; regnum++, addr += 4)
+    trad_frame_set_reg_addr (cache,
+			     regnum + gdbarch_num_regs (gdbarch),
+			     addr);
+
+  regnum = MIPS_PS_REGNUM;
+  trad_frame_set_reg_addr (cache,
+			   regnum + gdbarch_num_regs (gdbarch),
+			   ucontext_addr + 152);
+
+  /* HI and LO.  */
+  regnum = mips_regnum (gdbarch)->lo;
+  trad_frame_set_reg_addr (cache,
+			   regnum + gdbarch_num_regs (gdbarch),
+			   ucontext_addr + 156);
+  regnum = mips_regnum (gdbarch)->hi;
+  trad_frame_set_reg_addr (cache,
+			   regnum + gdbarch_num_regs (gdbarch),
+			   ucontext_addr + 160);
+
+  if (target_read_memory (ucontext_addr + 164, buf, 4) == 0 &&
+      extract_unsigned_integer (buf, 4, byte_order) != 0)
+    {
+      for (regnum = 0, addr = ucontext_addr + 168;
+	   regnum < 32; regnum++, addr += 8)
+	trad_frame_set_reg_addr (cache,
+				 regnum + gdbarch_fp0_regnum (gdbarch),
+				 addr);
+      trad_frame_set_reg_addr (cache, mips_regnum (gdbarch)->fp_control_status,
+			       addr);
+    }
+
+  trad_frame_set_id (cache, frame_id_build (sp, func));
+}
+
+static const struct tramp_frame mipsfbsd_sigframe =
+{
+  SIGTRAMP_FRAME,
+  MIPS_INSN32_SIZE,
+  {
+    { 0x27a40010, -1 },		/* addiu   a0, sp, SIGF_UC */
+    { 0x240201a1, -1 },		/* li      v0, SYS_sigreturn */
+    { 0x0000000c, -1 },		/* syscall */
+    { 0x0000000d, -1 },		/* break */
+    { TRAMP_SENTINEL_INSN, -1 }
+  },
+  mipsfbsd_sigframe_init
+};
+
+static void
+mips64fbsd_sigframe_init (const struct tramp_frame *self,
+			  struct frame_info *this_frame,
+			  struct trad_frame_cache *cache,
+			  CORE_ADDR func)
+{
+  struct gdbarch *gdbarch = get_frame_arch (this_frame);
+  enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
+  CORE_ADDR sp, ucontext_addr, addr;
+  int regnum;
+  gdb_byte buf[4];
+
+  /* We find the appropriate instance of `ucontext_t' at a
+     fixed offset in the signal frame.  */
+  sp = get_frame_register_signed (this_frame,
+				  MIPS_SP_REGNUM + gdbarch_num_regs (gdbarch));
+  ucontext_addr = sp + 32;
+
+  /* PC.  */
+  regnum = mips_regnum (gdbarch)->pc;
+  trad_frame_set_reg_addr (cache,
+			   regnum + gdbarch_num_regs (gdbarch),
+			    ucontext_addr + 24);
+
+  /* GPRs.  */
+  for (regnum = MIPS_AT_REGNUM, addr = ucontext_addr + 40;
+       regnum <= MIPS_RA_REGNUM; regnum++, addr += 8)
+    trad_frame_set_reg_addr (cache,
+			     regnum + gdbarch_num_regs (gdbarch),
+			     addr);
+
+  regnum = MIPS_PS_REGNUM;
+  trad_frame_set_reg_addr (cache,
+			   regnum + gdbarch_num_regs (gdbarch),
+			   ucontext_addr + 288);
+
+  /* HI and LO.  */
+  regnum = mips_regnum (gdbarch)->lo;
+  trad_frame_set_reg_addr (cache,
+			   regnum + gdbarch_num_regs (gdbarch),
+			   ucontext_addr + 296);
+  regnum = mips_regnum (gdbarch)->hi;
+  trad_frame_set_reg_addr (cache,
+			   regnum + gdbarch_num_regs (gdbarch),
+			   ucontext_addr + 304);
+
+  if (target_read_memory (ucontext_addr + 312, buf, 4) == 0 &&
+      extract_unsigned_integer (buf, 4, byte_order) != 0)
+    {
+      for (regnum = 0, addr = ucontext_addr + 320;
+	   regnum < 32; regnum++, addr += 8)
+	trad_frame_set_reg_addr (cache,
+				 regnum + gdbarch_fp0_regnum (gdbarch),
+				 addr);
+      trad_frame_set_reg_addr (cache, mips_regnum (gdbarch)->fp_control_status,
+			       addr);
+    }
+
+  trad_frame_set_id (cache, frame_id_build (sp, func));
+}
+
+static const struct tramp_frame mips64fbsd_sigframe =
+{
+  SIGTRAMP_FRAME,
+  MIPS_INSN32_SIZE,
+  {
+    { 0x67a40020, -1 },		/* daddiu  a0, sp, SIGF_UC */
+    { 0x240201a1, -1 },		/* li      v0, SYS_sigreturn */
+    { 0x0000000c, -1 },		/* syscall */
+    { 0x0000000d, -1 },		/* break */
+    { TRAMP_SENTINEL_INSN, -1 }
+  },
+  mips64fbsd_sigframe_init
+};
+
+/* Shared library support.  */
+
+/* FreeBSD/mips uses a slightly different `struct link_map' than the
+   other FreeBSD platforms as it includes an additional `l_off'
+   member.  */
+
+static struct link_map_offsets *
+mipsfbsd_ilp32_fetch_link_map_offsets (void)
+{
+  static struct link_map_offsets lmo;
+  static struct link_map_offsets *lmp = NULL;
+
+  if (lmp == NULL) 
+    {
+      lmp = &lmo;
+
+      lmo.r_version_offset = 0;
+      lmo.r_version_size = 4;
+      lmo.r_map_offset = 4;
+      lmo.r_brk_offset = 8;
+      lmo.r_ldsomap_offset = -1;
+
+      lmo.link_map_size = 24;
+      lmo.l_addr_offset = 0;
+      lmo.l_name_offset = 8;
+      lmo.l_ld_offset = 12;
+      lmo.l_next_offset = 16;
+      lmo.l_prev_offset = 20;
+    }
+
+  return lmp;
+}
+
+static struct link_map_offsets *
+mipsfbsd_lp64_fetch_link_map_offsets (void)
+{
+  static struct link_map_offsets lmo;
+  static struct link_map_offsets *lmp = NULL;
+
+  if (lmp == NULL)
+    {
+      lmp = &lmo;
+
+      lmo.r_version_offset = 0;
+      lmo.r_version_size = 4;
+      lmo.r_map_offset = 8;
+      lmo.r_brk_offset = 16;
+      lmo.r_ldsomap_offset = -1;
+
+      lmo.link_map_size = 48;
+      lmo.l_addr_offset = 0;
+      lmo.l_name_offset = 16; 
+      lmo.l_ld_offset = 24;
+      lmo.l_next_offset = 32;
+      lmo.l_prev_offset = 40;
+    }
+
+  return lmp;
+}
+
+static void
+mipsfbsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
+{
+  enum mips_abi abi = mips_abi (gdbarch);
+
+  /* Generic FreeBSD support.  */
+  fbsd_init_abi (info, gdbarch);
+
+  set_gdbarch_software_single_step (gdbarch, mips_software_single_step);
+
+  switch (abi)
+    {
+      case MIPS_ABI_O32:
+	tramp_frame_prepend_unwinder (gdbarch, &mipsfbsd_sigframe);
+	break;
+      case MIPS_ABI_N32:
+	/* Float formats similar to Linux?  */
+	break;
+      case MIPS_ABI_N64:
+	/* Float formats similar to Linux?  */
+	tramp_frame_prepend_unwinder (gdbarch, &mips64fbsd_sigframe);
+	break;
+    }
+
+  /* TODO: set_gdbarch_longjmp_target  */
+
+  set_gdbarch_iterate_over_regset_sections
+    (gdbarch, mipsfbsd_iterate_over_regset_sections);
+
+  /* FreeBSD/mips has SVR4-style shared libraries.  */
+  set_solib_svr4_fetch_link_map_offsets
+    (gdbarch, (gdbarch_ptr_bit (gdbarch) == 32 ?
+	       mipsfbsd_ilp32_fetch_link_map_offsets :
+	       mipsfbsd_lp64_fetch_link_map_offsets));
+}
+
+
+/* Provide a prototype to silence -Wmissing-prototypes.  */
+void _initialize_mipsfbsd_tdep (void);
+
+void
+_initialize_mipsfbsd_tdep (void)
+{
+  gdbarch_register_osabi (bfd_arch_mips, 0, GDB_OSABI_FREEBSD_ELF,
+			  mipsfbsd_init_abi);
+}
diff --git a/gdb/mips-fbsd-tdep.h b/gdb/mips-fbsd-tdep.h
new file mode 100644
index 0000000..dd344f3
--- /dev/null
+++ b/gdb/mips-fbsd-tdep.h
@@ -0,0 +1,28 @@ 
+/* Common target dependent code for GDB on MIPS systems running FreeBSD.
+
+   Copyright (C) 2016 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 3 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, see <http://www.gnu.org/licenses/>.  */
+
+#ifndef MIPS_FBSD_TDEP_H
+#define MIPS_FBSD_TDEP_H
+
+void mipsfbsd_supply_fpregs (struct regcache *, int, const void *, size_t);
+void mipsfbsd_supply_gregs (struct regcache *, int, const void *, size_t);
+void mipsfbsd_collect_fpregs (const struct regcache *, int, void *, size_t);
+void mipsfbsd_collect_gregs (const struct regcache *, int, void *, size_t);
+
+#endif /* MIPS_FBSD_TDEP_H */