[PATCH/SPARC] Add signal trampoline support for FreeBSD/sparc64

[Mark Kettenis <kettenis at chello dot nl>]

Committed to the SPARC branch.

Mark


Index: ChangeLog
from  Mark Kettenis  <kettenis@gnu.org>

	* sparc64fbsd-tdep.c: Include "frame.h", "frame-unwind.h",
	"trad-frame.h" and "gdb_assert.h".
	(BIAS): New define.
	(sparc64fbsd_pc_in_sigtramp, sparc64fbsd_sigtramp_frame_cache)
	(sparc64fbsd_sigtramp_frame_this_id)
	(sparc64fbsd_sigtramp_frame_prev_register): New functions.
	(sparc64fbsd_sigtramp_frame_unwind): New variable.
	(sparc64fbsd_sigtramp_frame_sniffer): New function.
	(sparc64fbsd_init_abi): Set pc_in_sigtramp, append
	sparc64fbsd_sigtramp_frame_sniffer.

Index: sparc64fbsd-tdep.c
===================================================================
RCS file: /cvs/src/src/gdb/sparc64fbsd-tdep.c,v
retrieving revision 1.2.6.2
diff -u -p -r1.2.6.2 sparc64fbsd-tdep.c
--- sparc64fbsd-tdep.c 26 Dec 2003 21:12:07 -0000 1.2.6.2
+++ sparc64fbsd-tdep.c 26 Dec 2003 23:18:42 -0000
@@ -20,15 +20,25 @@
    Boston, MA 02111-1307, USA.  */
 
 #include "defs.h"
+#include "frame.h"
+#include "frame-unwind.h"
 #include "gdbcore.h"
 #include "osabi.h"
 #include "regcache.h"
 #include "target.h"
+#include "trad-frame.h"
 
+#include "gdb_assert.h"
 #include "gdb_string.h"
 
 #include "sparc64-tdep.h"
 
+/* The stack pointer is offset from the stack frame by a BIAS of 2047
+   (0x7ff) for 64-bit code.  BIAS is likely to be defined on SPARC
+   hosts, so undefine it first.  */
+#undef BIAS
+#define BIAS 2047
+
 /* From <machine/reg.h>.  */
 const struct sparc_gregset sparc64fbsd_gregset =
 {
@@ -85,9 +95,140 @@ static struct core_fns sparc64fbsd_core_
 };
 
 
+/* Signal trampolines.  */
+
+static int
+sparc64fbsd_pc_in_sigtramp (CORE_ADDR pc, char *name)
+{
+  return (name && strcmp (name, "__sigtramp") == 0);
+}
+
+static struct sparc_frame_cache *
+sparc64fbsd_sigtramp_frame_cache (struct frame_info *next_frame,
+				   void **this_cache)
+{
+  struct sparc_frame_cache *cache;
+  CORE_ADDR addr, mcontext_addr, sp;
+  LONGEST fprs;
+  int regnum;
+
+  if (*this_cache)
+    return *this_cache;
+
+  cache = sparc_frame_cache (next_frame, this_cache);
+  gdb_assert (cache == *this_cache);
+
+  cache->saved_regs = trad_frame_alloc_saved_regs (next_frame);
+
+  /* The third argument is a pointer to an instance of `ucontext_t',
+     which has a member `uc_mcontext' that contains the saved
+     registers.  */
+  addr = frame_unwind_register_unsigned (next_frame, SPARC_O2_REGNUM);
+  mcontext_addr = addr + 64;
+
+  /* The following registers travel in the `mc_local' slots of
+     `mcontext_t'.  */
+  addr = mcontext_addr + 16 * 8;
+  cache->saved_regs[SPARC64_FPRS_REGNUM].addr = addr + 0 * 8;
+  cache->saved_regs[SPARC64_FSR_REGNUM].addr = addr + 1 * 8;
+
+  /* The following registers travel in the `mc_in' slots of
+     `mcontext_t'.  */
+  addr = mcontext_addr + 24 * 8;
+  cache->saved_regs[SPARC64_NPC_REGNUM].addr = addr + 0 * 8;
+  cache->saved_regs[SPARC64_PC_REGNUM].addr = addr + 1 * 8;
+  cache->saved_regs[SPARC64_STATE_REGNUM].addr = addr + 2 * 8;
+  cache->saved_regs[SPARC64_Y_REGNUM].addr = addr + 4 * 8;
+
+  /* The `global' and `out' registers travel in the `mc_global' and
+     `mc_out' slots of `mcontext_t', except for %g0.  Since %g0 is
+     always zero, keep the identity encoding.  */
+  for (regnum = SPARC_G1_REGNUM, addr = mcontext_addr + 8;
+       regnum <= SPARC_O7_REGNUM; regnum++, addr += 8)
+    cache->saved_regs[regnum].addr = addr;
+
+  /* The `local' and `in' registers have been saved in the register
+     save areas.  */
+  addr = cache->saved_regs[SPARC_SP_REGNUM].addr;
+  sp = get_frame_memory_unsigned (next_frame, addr, 8);
+  for (regnum = SPARC_L0_REGNUM, addr = sp + BIAS;
+       regnum <= SPARC_I7_REGNUM; regnum++, addr += 8)
+    cache->saved_regs[regnum].addr = addr;
+
+  /* The floating-point registers are only saved if the FEF bit in
+     %fprs has been set.  */
+
+#define FPRS_FEF	(1 << 2)
+
+  addr = cache->saved_regs[SPARC64_FPRS_REGNUM].addr;
+  fprs = get_frame_memory_unsigned (next_frame, addr, 8);
+  if (fprs & (1 << 2))
+    {
+      for (regnum = SPARC_F0_REGNUM, addr = mcontext_addr + 32 * 8;
+	   regnum <= SPARC_F31_REGNUM; regnum++, addr += 4)
+	cache->saved_regs[regnum].addr = addr;
+
+      for (regnum = SPARC64_F32_REGNUM;
+	   regnum <= SPARC64_F62_REGNUM; regnum++, addr += 8)
+	cache->saved_regs[regnum].addr = addr;
+    }
+
+  return cache;
+}
+
+static void
+sparc64fbsd_sigtramp_frame_this_id (struct frame_info *next_frame,
+				    void **this_cache,
+				    struct frame_id *this_id)
+{
+  struct sparc_frame_cache *cache =
+    sparc64fbsd_sigtramp_frame_cache (next_frame, this_cache);
+
+  (*this_id) = frame_id_build (cache->base, cache->pc);
+}
+
+static void
+sparc64fbsd_sigtramp_frame_prev_register (struct frame_info *next_frame,
+					  void **this_cache,
+					  int regnum, int *optimizedp,
+					  enum lval_type *lvalp,
+					  CORE_ADDR *addrp,
+					  int *realnump, void *valuep)
+{
+  struct sparc_frame_cache *cache =
+    sparc64fbsd_sigtramp_frame_cache (next_frame, this_cache);
+
+  trad_frame_prev_register (next_frame, cache->saved_regs, regnum,
+			    optimizedp, lvalp, addrp, realnump, valuep);
+}
+
+static const struct frame_unwind sparc64fbsd_sigtramp_frame_unwind =
+{
+  SIGTRAMP_FRAME,
+  sparc64fbsd_sigtramp_frame_this_id,
+  sparc64fbsd_sigtramp_frame_prev_register
+};
+
+static const struct frame_unwind *
+sparc64fbsd_sigtramp_frame_sniffer (struct frame_info *next_frame)
+{
+  CORE_ADDR pc = frame_pc_unwind (next_frame);
+  char *name;
+
+  find_pc_partial_function (pc, &name, NULL, NULL);
+  if (sparc64fbsd_pc_in_sigtramp (pc, name))
+    return &sparc64fbsd_sigtramp_frame_unwind;
+
+  return NULL;
+}
+
+
 static void
 sparc64fbsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
 {
+  set_gdbarch_pc_in_sigtramp (gdbarch, sparc64fbsd_pc_in_sigtramp);
+  frame_unwind_append_sniffer (gdbarch, sparc64fbsd_sigtramp_frame_sniffer);
+
   sparc64_init_abi (info, gdbarch);
 }