X-Git-Url: http://drtracing.org/?a=blobdiff_plain;f=gdb%2Famd64obsd-tdep.c;h=2460e009d93bf46f8752aac67b092669e5a7638f;hb=9b254dd1ce46c19dde1dde5b8d1e22e862dfacce;hp=01cc559575fe15a589d4ba44809e027e50879942;hpb=617a4cbacf3fae7fb4eb43708b127bd19dc1623b;p=deliverable%2Fbinutils-gdb.git

diff --git a/gdb/amd64obsd-tdep.c b/gdb/amd64obsd-tdep.c
index 01cc559575..2460e009d9 100644
--- a/gdb/amd64obsd-tdep.c
+++ b/gdb/amd64obsd-tdep.c
@@ -1,12 +1,12 @@
 /* Target-dependent code for OpenBSD/amd64.
 
-   Copyright 2003, 2004 Free Software Foundation, Inc.
+   Copyright (C) 2003, 2004, 2005, 2007, 2008 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
+   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,
@@ -15,18 +15,19 @@
    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.  */
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
 
 #include "defs.h"
 #include "frame.h"
+#include "frame-unwind.h"
 #include "gdbcore.h"
 #include "symtab.h"
 #include "objfiles.h"
 #include "osabi.h"
+#include "regcache.h"
 #include "regset.h"
 #include "target.h"
+#include "trad-frame.h"
 
 #include "gdb_assert.h"
 #include "gdb_string.h"
@@ -34,6 +35,7 @@
 #include "amd64-tdep.h"
 #include "i387-tdep.h"
 #include "solib-svr4.h"
+#include "bsd-uthread.h"
 
 /* Support for core dumps.  */
 
@@ -42,12 +44,13 @@ amd64obsd_supply_regset (const struct regset *regset,
 			 struct regcache *regcache, int regnum,
 			 const void *regs, size_t len)
 {
-  const struct gdbarch_tdep *tdep = regset->descr;
+  const struct gdbarch_tdep *tdep = gdbarch_tdep (regset->arch);
 
   gdb_assert (len >= tdep->sizeof_gregset + I387_SIZEOF_FXSAVE);
 
   i386_supply_gregset (regset, regcache, regnum, regs, tdep->sizeof_gregset);
-  amd64_supply_fxsave (regcache, regnum, (char *)regs + tdep->sizeof_gregset);
+  amd64_supply_fxsave (regcache, regnum,
+		       ((const gdb_byte *)regs) + tdep->sizeof_gregset);
 }
 
 static const struct regset *
@@ -63,8 +66,7 @@ amd64obsd_regset_from_core_section (struct gdbarch *gdbarch,
       && sect_size >= tdep->sizeof_gregset + I387_SIZEOF_FXSAVE)
     {
       if (tdep->gregset == NULL)
-        tdep->gregset = regset_alloc (gdbarch, tdep,
-                                      amd64obsd_supply_regset, NULL);
+        tdep->gregset = regset_alloc (gdbarch, amd64obsd_supply_regset, NULL);
       return tdep->gregset;
     }
 
@@ -85,13 +87,15 @@ amd64obsd_sigtramp_p (struct frame_info *next_frame)
 {
   CORE_ADDR pc = frame_pc_unwind (next_frame);
   CORE_ADDR start_pc = (pc & ~(amd64obsd_page_size - 1));
-  const char sigreturn[] =
+  const gdb_byte sigreturn[] =
   {
     0x48, 0xc7, 0xc0,
     0x67, 0x00, 0x00, 0x00,	/* movq $SYS_sigreturn, %rax */
     0xcd, 0x80			/* int $0x80 */
   };
-  char *name, *buf;
+  size_t buflen = (sizeof sigreturn) + 1;
+  gdb_byte *buf;
+  char *name;
 
   /* If the function has a valid symbol name, it isn't a
      trampoline.  */
@@ -105,12 +109,15 @@ amd64obsd_sigtramp_p (struct frame_info *next_frame)
     return 0;
 
   /* If we can't read the instructions at START_PC, return zero.  */
-  buf = alloca (sizeof sigreturn);
-  if (target_read_memory (start_pc + 7, buf, sizeof sigreturn))
+  buf = alloca ((sizeof sigreturn) + 1);
+  if (!safe_frame_unwind_memory (next_frame, start_pc + 6, buf, buflen))
     return 0;
 
-  /* Check for sigreturn(2).  */
-  if (memcmp (buf, sigreturn, sizeof sigreturn))
+  /* Check for sigreturn(2).  Depending on how the assembler encoded
+     the `movq %rsp, %rdi' instruction, the code starts at offset 6 or
+     7.  */
+  if (memcmp (buf, sigreturn, sizeof sigreturn)
+      && memcpy (buf + 1, sigreturn, sizeof sigreturn))
     return 0;
 
   return 1;
@@ -137,7 +144,7 @@ amd64obsd_sigcontext_addr (struct frame_info *next_frame)
      (see /usr/src/sys/arch/amd64/amd64/locore.S).  The `pushq'
      instruction clobbers %rsp, but its value is saved in `%rdi'.  */
 
-  if (offset > 6)
+  if (offset > 5)
     return frame_unwind_register_unsigned (next_frame, AMD64_RDI_REGNUM);
   else
     return frame_unwind_register_unsigned (next_frame, AMD64_RSP_REGNUM);
@@ -206,6 +213,236 @@ static int amd64obsd_sc_reg_offset[] =
   15 * 8			/* %gs */
 };
 
+/* From /usr/src/lib/libpthread/arch/amd64/uthread_machdep.c.  */
+static int amd64obsd_uthread_reg_offset[] =
+{
+  19 * 8,			/* %rax */
+  16 * 8,			/* %rbx */
+  18 * 8,			/* %rcx */
+  17 * 8,			/* %rdx */
+  14 * 8,			/* %rsi */
+  13 * 8,			/* %rdi */
+  15 * 8,			/* %rbp */
+  -1,				/* %rsp */
+  12 * 8,			/* %r8 ... */
+  11 * 8,
+  10 * 8,
+  9 * 8,
+  8 * 8,
+  7 * 8,
+  6 * 8,
+  5 * 8,			/* ... %r15 */
+  20 * 8,			/* %rip */
+  4 * 8,			/* %eflags */
+  21 * 8,			/* %cs */
+  -1,				/* %ss */
+  3 * 8,			/* %ds */
+  2 * 8,			/* %es */
+  1 * 8,			/* %fs */
+  0 * 8				/* %gs */
+};
+
+/* Offset within the thread structure where we can find the saved
+   stack pointer (%esp).  */
+#define AMD64OBSD_UTHREAD_RSP_OFFSET	400
+
+static void
+amd64obsd_supply_uthread (struct regcache *regcache,
+			  int regnum, CORE_ADDR addr)
+{
+  CORE_ADDR sp_addr = addr + AMD64OBSD_UTHREAD_RSP_OFFSET;
+  CORE_ADDR sp = 0;
+  gdb_byte buf[8];
+  int i;
+
+  gdb_assert (regnum >= -1);
+
+  if (regnum == -1 || regnum == AMD64_RSP_REGNUM)
+    {
+      int offset;
+
+      /* Fetch stack pointer from thread structure.  */
+      sp = read_memory_unsigned_integer (sp_addr, 8);
+
+      /* Adjust the stack pointer such that it looks as if we just
+         returned from _thread_machdep_switch.  */
+      offset = amd64obsd_uthread_reg_offset[AMD64_RIP_REGNUM] + 8;
+      store_unsigned_integer (buf, 8, sp + offset);
+      regcache_raw_supply (regcache, AMD64_RSP_REGNUM, buf);
+    }
+
+  for (i = 0; i < ARRAY_SIZE (amd64obsd_uthread_reg_offset); i++)
+    {
+      if (amd64obsd_uthread_reg_offset[i] != -1
+	  && (regnum == -1 || regnum == i))
+	{
+	  /* Fetch stack pointer from thread structure (if we didn't
+             do so already).  */
+	  if (sp == 0)
+	    sp = read_memory_unsigned_integer (sp_addr, 8);
+
+	  /* Read the saved register from the stack frame.  */
+	  read_memory (sp + amd64obsd_uthread_reg_offset[i], buf, 8);
+	  regcache_raw_supply (regcache, i, buf);
+	}
+    }
+}
+
+static void
+amd64obsd_collect_uthread (const struct regcache *regcache,
+			   int regnum, CORE_ADDR addr)
+{
+  CORE_ADDR sp_addr = addr + AMD64OBSD_UTHREAD_RSP_OFFSET;
+  CORE_ADDR sp = 0;
+  gdb_byte buf[8];
+  int i;
+
+  gdb_assert (regnum >= -1);
+
+  if (regnum == -1 || regnum == AMD64_RSP_REGNUM)
+    {
+      int offset;
+
+      /* Calculate the stack pointer (frame pointer) that will be
+         stored into the thread structure.  */
+      offset = amd64obsd_uthread_reg_offset[AMD64_RIP_REGNUM] + 8;
+      regcache_raw_collect (regcache, AMD64_RSP_REGNUM, buf);
+      sp = extract_unsigned_integer (buf, 8) - offset;
+
+      /* Store the stack pointer.  */
+      write_memory_unsigned_integer (sp_addr, 8, sp);
+
+      /* The stack pointer was (potentially) modified.  Make sure we
+         build a proper stack frame.  */
+      regnum = -1;
+    }
+
+  for (i = 0; i < ARRAY_SIZE (amd64obsd_uthread_reg_offset); i++)
+    {
+      if (amd64obsd_uthread_reg_offset[i] != -1
+	  && (regnum == -1 || regnum == i))
+	{
+	  /* Fetch stack pointer from thread structure (if we didn't
+             calculate it already).  */
+	  if (sp == 0)
+	    sp = read_memory_unsigned_integer (sp_addr, 8);
+
+	  /* Write the register into the stack frame.  */
+	  regcache_raw_collect (regcache, i, buf);
+	  write_memory (sp + amd64obsd_uthread_reg_offset[i], buf, 8);
+	}
+    }
+}
+/* Kernel debugging support.  */
+
+/* From <machine/frame.h>.  Easy since `struct trapframe' matches
+   `struct sigcontext'.  */
+#define amd64obsd_tf_reg_offset amd64obsd_sc_reg_offset
+
+static struct trad_frame_cache *
+amd64obsd_trapframe_cache(struct frame_info *next_frame, void **this_cache)
+{
+  struct trad_frame_cache *cache;
+  CORE_ADDR func, sp, addr;
+  ULONGEST cs;
+  char *name;
+  int i;
+
+  if (*this_cache)
+    return *this_cache;
+
+  cache = trad_frame_cache_zalloc (next_frame);
+  *this_cache = cache;
+
+  /* NORMAL_FRAME matches the type in amd64obsd_trapframe_unwind, but
+     SIGTRAMP_FRAME might be more appropriate.  */
+  func = frame_func_unwind (next_frame, NORMAL_FRAME);
+  sp = frame_unwind_register_unsigned (next_frame, AMD64_RSP_REGNUM);
+
+  find_pc_partial_function (func, &name, NULL, NULL);
+  if (name && strncmp (name, "Xintr", 5) == 0)
+    addr = sp + 8;		/* It's an interrupt frame.  */
+  else
+    addr = sp;
+
+  for (i = 0; i < ARRAY_SIZE (amd64obsd_tf_reg_offset); i++)
+    if (amd64obsd_tf_reg_offset[i] != -1)
+      trad_frame_set_reg_addr (cache, i, addr + amd64obsd_tf_reg_offset[i]);
+
+  /* Read %cs from trap frame.  */
+  addr += amd64obsd_tf_reg_offset[AMD64_CS_REGNUM];
+  cs = read_memory_unsigned_integer (addr, 8); 
+  if ((cs & I386_SEL_RPL) == I386_SEL_UPL)
+    {
+      /* Trap from user space; terminate backtrace.  */
+      trad_frame_set_id (cache, null_frame_id);
+    }
+  else
+    {
+      /* Construct the frame ID using the function start.  */
+      trad_frame_set_id (cache, frame_id_build (sp + 16, func));
+    }
+
+  return cache;
+}
+
+static void
+amd64obsd_trapframe_this_id (struct frame_info *next_frame,
+			     void **this_cache, struct frame_id *this_id)
+{
+  struct trad_frame_cache *cache =
+    amd64obsd_trapframe_cache (next_frame, this_cache);
+  
+  trad_frame_get_id (cache, this_id);
+}
+
+static void
+amd64obsd_trapframe_prev_register (struct frame_info *next_frame,
+				   void **this_cache, int regnum,
+				   int *optimizedp, enum lval_type *lvalp,
+				   CORE_ADDR *addrp, int *realnump,
+				   gdb_byte *valuep)
+{
+  struct trad_frame_cache *cache =
+    amd64obsd_trapframe_cache (next_frame, this_cache);
+
+  trad_frame_get_register (cache, next_frame, regnum,
+			   optimizedp, lvalp, addrp, realnump, valuep);
+}
+
+static int
+amd64obsd_trapframe_sniffer (const struct frame_unwind *self,
+			     struct frame_info *next_frame,
+			     void **this_prologue_cache)
+{
+  ULONGEST cs;
+  char *name;
+
+  /* Check Current Privilege Level and bail out if we're not executing
+     in kernel space.  */
+  cs = frame_unwind_register_unsigned (next_frame, AMD64_CS_REGNUM);
+  if ((cs & I386_SEL_RPL) == I386_SEL_UPL)
+    return 0;
+
+  find_pc_partial_function (frame_pc_unwind (next_frame), &name, NULL, NULL);
+  return (name && ((strcmp (name, "calltrap") == 0)
+		   || (strcmp (name, "osyscall1") == 0)
+		   || (strcmp (name, "Xsyscall") == 0)
+		   || (strncmp (name, "Xintr", 5) == 0)));
+}
+
+static const struct frame_unwind amd64obsd_trapframe_unwind = {
+  /* FIXME: kettenis/20051219: This really is more like an interrupt
+     frame, but SIGTRAMP_FRAME would print <signal handler called>,
+     which really is not what we want here.  */
+  NORMAL_FRAME,
+  amd64obsd_trapframe_this_id,
+  amd64obsd_trapframe_prev_register,
+  NULL,
+  amd64obsd_trapframe_sniffer
+};
+
+
 static void
 amd64obsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
 {
@@ -228,9 +465,16 @@ amd64obsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
   tdep->sc_reg_offset = amd64obsd_sc_reg_offset;
   tdep->sc_num_regs = ARRAY_SIZE (amd64obsd_sc_reg_offset);
 
+  /* OpenBSD provides a user-level threads implementation.  */
+  bsd_uthread_set_supply_uthread (gdbarch, amd64obsd_supply_uthread);
+  bsd_uthread_set_collect_uthread (gdbarch, amd64obsd_collect_uthread);
+
   /* OpenBSD uses SVR4-style shared libraries.  */
   set_solib_svr4_fetch_link_map_offsets
     (gdbarch, svr4_lp64_fetch_link_map_offsets);
+
+  /* Unwind kernel trap frames correctly.  */
+  frame_unwind_prepend_unwinder (gdbarch, &amd64obsd_trapframe_unwind);
 }