1 files changed, 258 insertions, 0 deletions
diff --git a/gdb/sparc-obsd-tdep.c b/gdb/sparc-obsd-tdep.c
new file mode 100644
index 0000000..21c8d6a
--- /dev/null
+++ b/gdb/sparc-obsd-tdep.c
@@ -0,0 +1,258 @@
+/* Target-dependent code for OpenBSD/sparc.
+
+   Copyright (C) 2004-2016 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/>.  */
+
+#include "defs.h"
+#include "floatformat.h"
+#include "frame.h"
+#include "frame-unwind.h"
+#include "gdbcore.h"
+#include "osabi.h"
+#include "regcache.h"
+#include "symtab.h"
+#include "trad-frame.h"
+
+#include "obsd-tdep.h"
+#include "sparc-tdep.h"
+#include "solib-svr4.h"
+#include "bsd-uthread.h"
+
+/* Signal trampolines.  */
+
+/* The OpenBSD kernel maps the signal trampoline at some random
+   location in user space, which means that the traditional BSD way of
+   detecting it won't work.
+
+   The signal trampoline will be mapped at an address that is page
+   aligned.  We recognize the signal trampoline by looking for the
+   sigreturn system call.  */
+
+static const int sparc32obsd_page_size = 4096;
+
+static int
+sparc32obsd_pc_in_sigtramp (CORE_ADDR pc, const char *name)
+{
+  CORE_ADDR start_pc = (pc & ~(sparc32obsd_page_size - 1));
+  unsigned long insn;
+
+  if (name)
+    return 0;
+
+  /* Check for "restore %g0, SYS_sigreturn, %g1".  */
+  insn = sparc_fetch_instruction (start_pc + 0xec);
+  if (insn != 0x83e82067)
+    return 0;
+
+  /* Check for "t ST_SYSCALL".  */
+  insn = sparc_fetch_instruction (start_pc + 0xf4);
+  if (insn != 0x91d02000)
+    return 0;
+
+  return 1;
+}
+
+static struct sparc_frame_cache *
+sparc32obsd_sigtramp_frame_cache (struct frame_info *this_frame,
+				  void **this_cache)
+{
+  struct sparc_frame_cache *cache;
+  CORE_ADDR addr;
+
+  if (*this_cache)
+    return (struct sparc_frame_cache *) *this_cache;
+
+  cache = sparc_frame_cache (this_frame, this_cache);
+  gdb_assert (cache == *this_cache);
+
+  /* If we couldn't find the frame's function, we're probably dealing
+     with an on-stack signal trampoline.  */
+  if (cache->pc == 0)
+    {
+      cache->pc = get_frame_pc (this_frame);
+      cache->pc &= ~(sparc32obsd_page_size - 1);
+
+      /* Since we couldn't find the frame's function, the cache was
+         initialized under the assumption that we're frameless.  */
+      sparc_record_save_insn (cache);
+      addr = get_frame_register_unsigned (this_frame, SPARC_FP_REGNUM);
+      cache->base = addr;
+    }
+
+  cache->saved_regs = sparc32nbsd_sigcontext_saved_regs (this_frame);
+
+  return cache;
+}
+
+static void
+sparc32obsd_sigtramp_frame_this_id (struct frame_info *this_frame,
+				    void **this_cache,
+				    struct frame_id *this_id)
+{
+  struct sparc_frame_cache *cache =
+    sparc32obsd_sigtramp_frame_cache (this_frame, this_cache);
+
+  (*this_id) = frame_id_build (cache->base, cache->pc);
+}
+
+static struct value *
+sparc32obsd_sigtramp_frame_prev_register (struct frame_info *this_frame,
+					  void **this_cache, int regnum)
+{
+  struct sparc_frame_cache *cache =
+    sparc32obsd_sigtramp_frame_cache (this_frame, this_cache);
+
+  return trad_frame_get_prev_register (this_frame, cache->saved_regs, regnum);
+}
+
+static int
+sparc32obsd_sigtramp_frame_sniffer (const struct frame_unwind *self,
+				    struct frame_info *this_frame,
+				    void **this_cache)
+{
+  CORE_ADDR pc = get_frame_pc (this_frame);
+  const char *name;
+
+  find_pc_partial_function (pc, &name, NULL, NULL);
+  if (sparc32obsd_pc_in_sigtramp (pc, name))
+    return 1;
+
+  return 0;
+}
+static const struct frame_unwind sparc32obsd_sigtramp_frame_unwind =
+{
+  SIGTRAMP_FRAME,
+  default_frame_unwind_stop_reason,
+  sparc32obsd_sigtramp_frame_this_id,
+  sparc32obsd_sigtramp_frame_prev_register,
+  NULL,
+  sparc32obsd_sigtramp_frame_sniffer
+};
+
+
+
+/* Offset wthin the thread structure where we can find %fp and %i7.  */
+#define SPARC32OBSD_UTHREAD_FP_OFFSET	128
+#define SPARC32OBSD_UTHREAD_PC_OFFSET	132
+
+static void
+sparc32obsd_supply_uthread (struct regcache *regcache,
+			    int regnum, CORE_ADDR addr)
+{
+  struct gdbarch *gdbarch = get_regcache_arch (regcache);
+  enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
+  CORE_ADDR fp, fp_addr = addr + SPARC32OBSD_UTHREAD_FP_OFFSET;
+  gdb_byte buf[4];
+
+  gdb_assert (regnum >= -1);
+
+  fp = read_memory_unsigned_integer (fp_addr, 4, byte_order);
+  if (regnum == SPARC_SP_REGNUM || regnum == -1)
+    {
+      store_unsigned_integer (buf, 4, byte_order, fp);
+      regcache_raw_supply (regcache, SPARC_SP_REGNUM, buf);
+
+      if (regnum == SPARC_SP_REGNUM)
+	return;
+    }
+
+  if (regnum == SPARC32_PC_REGNUM || regnum == SPARC32_NPC_REGNUM
+      || regnum == -1)
+    {
+      CORE_ADDR i7, i7_addr = addr + SPARC32OBSD_UTHREAD_PC_OFFSET;
+
+      i7 = read_memory_unsigned_integer (i7_addr, 4, byte_order);
+      if (regnum == SPARC32_PC_REGNUM || regnum == -1)
+	{
+	  store_unsigned_integer (buf, 4, byte_order, i7 + 8);
+	  regcache_raw_supply (regcache, SPARC32_PC_REGNUM, buf);
+	}
+      if (regnum == SPARC32_NPC_REGNUM || regnum == -1)
+	{
+	  store_unsigned_integer (buf, 4, byte_order, i7 + 12);
+	  regcache_raw_supply (regcache, SPARC32_NPC_REGNUM, buf);
+	}
+
+      if (regnum == SPARC32_PC_REGNUM || regnum == SPARC32_NPC_REGNUM)
+	return;
+    }
+
+  sparc_supply_rwindow (regcache, fp, regnum);
+}
+
+static void
+sparc32obsd_collect_uthread(const struct regcache *regcache,
+			    int regnum, CORE_ADDR addr)
+{
+  struct gdbarch *gdbarch = get_regcache_arch (regcache);
+  enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
+  CORE_ADDR sp;
+  gdb_byte buf[4];
+
+  gdb_assert (regnum >= -1);
+
+  if (regnum == SPARC_SP_REGNUM || regnum == -1)
+    {
+      CORE_ADDR fp_addr = addr + SPARC32OBSD_UTHREAD_FP_OFFSET;
+
+      regcache_raw_collect (regcache, SPARC_SP_REGNUM, buf);
+      write_memory (fp_addr,buf, 4);
+    }
+
+  if (regnum == SPARC32_PC_REGNUM || regnum == -1)
+    {
+      CORE_ADDR i7, i7_addr = addr + SPARC32OBSD_UTHREAD_PC_OFFSET;
+
+      regcache_raw_collect (regcache, SPARC32_PC_REGNUM, buf);
+      i7 = extract_unsigned_integer (buf, 4, byte_order) - 8;
+      write_memory_unsigned_integer (i7_addr, 4, byte_order, i7);
+
+      if (regnum == SPARC32_PC_REGNUM)
+	return;
+    }
+
+  regcache_raw_collect (regcache, SPARC_SP_REGNUM, buf);
+  sp = extract_unsigned_integer (buf, 4, byte_order);
+  sparc_collect_rwindow (regcache, sp, regnum);
+}
+
+
+static void
+sparc32obsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
+{
+  /* OpenBSD/sparc is very similar to NetBSD/sparc ELF.  */
+  sparc32nbsd_elf_init_abi (info, gdbarch);
+
+  set_gdbarch_skip_solib_resolver (gdbarch, obsd_skip_solib_resolver);
+
+  frame_unwind_append_unwinder (gdbarch, &sparc32obsd_sigtramp_frame_unwind);
+
+  /* OpenBSD provides a user-level threads implementation.  */
+  bsd_uthread_set_supply_uthread (gdbarch, sparc32obsd_supply_uthread);
+  bsd_uthread_set_collect_uthread (gdbarch, sparc32obsd_collect_uthread);
+}
+
+
+/* Provide a prototype to silence -Wmissing-prototypes.  */
+void _initialize_sparc32obsd_tdep (void);
+
+void
+_initialize_sparc32obsd_tdep (void)
+{
+  gdbarch_register_osabi (bfd_arch_sparc, 0, GDB_OSABI_OPENBSD_ELF,
+			  sparc32obsd_init_abi);
+}