* frame.h: Move definition of struct frame_saved_args to before

	struct frame to make it possible to use frame_saved_args in
	EXTRA_FRAME_INFO macro.

	* v850-tdep.c config/v850/tm-v850.h:  Lotsa new functions and
	macros to make frame operations (such as backtrace) work.

1 files changed, 216 insertions, 0 deletions

diff --git a/gdb/v850-tdep.c b/gdb/v850-tdep.c
index b710920..7363fc2 100644
--- a/gdb/v850-tdep.c
+++ b/gdb/v850-tdep.c
@@ -30,6 +30,222 @@ Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
 #include "gdb_string.h"
 
 #include "gdbcore.h"
+
+
+/* This function actually figures out the frame address for a given pc and
+   sp.  This is tricky on the v850 because we only use an explicit frame
+   pointer when using alloca().  The only reliable way to get this info is to
+   examine the prologue.
+*/
+
+void
+v850_init_extra_frame_info (fi)
+     struct frame_info *fi;
+{
+  struct symtab_and_line sal;
+  CORE_ADDR func_addr, prologue_end, current_pc;
+  int reg;
+  int frameoffset;
+  int framereg;
+
+  if (fi->next)
+    fi->pc = v850_find_callers_reg (fi->next, RP_REGNUM);
+
+  /* First, figure out the bounds of the prologue so that we can limit the
+     search to something reasonable.  */
+
+  if (find_pc_partial_function (fi->pc, NULL, &func_addr, NULL))
+    {
+      sal = find_pc_line (func_addr, 0);
+
+      prologue_end = sal.end;
+    }
+  else
+    prologue_end = func_addr + 100; /* We're in the boondocks */
+
+  prologue_end = min (prologue_end, fi->pc);
+
+  /* Now, search the prologue looking for instructions that setup fp, save
+     rp, adjust sp and such. */ 
+
+  framereg = SP_REGNUM;
+  frameoffset = 0;
+  memset (fi->fsr.regs, '\000', sizeof fi->fsr.regs);
+
+  for (current_pc = func_addr; current_pc < prologue_end; current_pc += 2)
+    {
+      int insn;
+
+      insn = read_memory_integer (current_pc, 2);
+
+      if ((insn & 0xffe0) == ((SP_REGNUM << 11) | 0x0240)) /* add <imm>,sp */
+	frameoffset = (insn & 0x1f) | ~0x1f;
+      else if (insn == ((SP_REGNUM << 11) | 0x0600 | SP_REGNUM)) /* addi <imm>,sp,sp */
+	{
+	  current_pc += 2;
+
+	  frameoffset = read_memory_integer (current_pc, 2);
+	}
+      else if (insn == ((FP_REGNUM << 11) | 0x0000 | 12)) /* mov r12,r2 */
+	framereg = FP_REGNUM;	/* Setting up fp */
+      else if ((insn & 0x07ff) == (0x0760 | SP_REGNUM))	/* st.w <reg>,<offset>[sp] */
+	{
+	  reg = (insn >> 11) & 0x1f;	/* Extract <reg> */
+	  current_pc += 2;
+
+	  insn = read_memory_integer (current_pc, 2) & ~1;
+
+	  fi->fsr.regs[reg] = insn + frameoffset;
+	}
+      else if ((insn & 0x07ff) == (0x0760 | FP_REGNUM))	/* st.w <reg>,<offset>[fp] */
+	{
+	  reg = (insn >> 11) & 0x1f;	/* Extract <reg> */
+	  current_pc += 2;
+
+	  insn = read_memory_integer (current_pc, 2) & ~1;
+
+	  fi->fsr.regs[reg] = insn;
+	}
+    }
+
+#if 0
+  if (!fi->next)
+    fi->frame = read_register (framereg);
+  else
+    if (framereg == SP_REGNUM)
+      fi->frame = fi->next->frame;
+    else
+      fi->frame = v850_find_callers_reg (fi, framereg);
+
+  if (framereg == SP_REGNUM)
+    fi->frame -= frameoffset;
+#else
+  if (!fi->next && framereg == SP_REGNUM)
+    fi->frame = read_register (framereg) - frameoffset;
+#endif
+
+  for (reg = 0; reg < NUM_REGS; reg++)
+    if (fi->fsr.regs[reg] != 0)
+      fi->fsr.regs[reg] += fi->frame;
+}
+
+/* Find the caller of this frame.  We do this by seeing if RP_REGNUM is saved
+   in the stack anywhere, otherwise we get it from the registers. */
+
+CORE_ADDR
+v850_find_callers_reg (fi, regnum)
+     struct frame_info *fi;
+     int regnum;
+{
+  for (; fi; fi = fi->next)
+    if (fi->fsr.regs[regnum] != 0)
+      return read_memory_integer (fi->fsr.regs[regnum], 4);
+
+  return read_register (regnum);
+}
+
+CORE_ADDR
+v850_frame_chain (fi)
+     struct frame_info *fi;
+{
+  CORE_ADDR callers_pc, callers_sp;
+  struct frame_info temp_fi;
+  CORE_ADDR func_addr, prologue_end, current_pc;
+  int frameoffset;
+
+  /* First, find out who called us */
+
+  callers_pc = v850_find_callers_reg (fi, RP_REGNUM);
+
+  /* Next, figure out where his prologue is.  */
+
+  if (find_pc_partial_function (callers_pc, NULL, &func_addr, NULL))
+    {
+      struct symtab_and_line sal;
+
+      sal = find_pc_line (func_addr, 0);
+
+      prologue_end = sal.end;
+    }
+  else
+    prologue_end = func_addr + 100; /* We're in the boondocks */
+
+  prologue_end = min (prologue_end, callers_pc);
+
+  /* Now, figure out the frame location of the caller by examining his prologue.
+     We're looking for either a load of the frame pointer register, or a stack
+     adjustment. */
+
+  frameoffset = 0;
+
+  for (current_pc = func_addr; current_pc < prologue_end; current_pc += 2)
+    {
+      int insn;
+
+      insn = read_memory_integer (current_pc, 2);
+
+      if ((insn & 0xffe0) == ((SP_REGNUM << 11) | 0x0240)) /* add <imm>,sp */
+	frameoffset = (insn & 0x1f) | ~0x1f;
+      else if (insn == ((SP_REGNUM << 11) | 0x0600 | SP_REGNUM)) /* addi <imm>,sp,sp */
+	{
+	  current_pc += 2;
+
+	  frameoffset = read_memory_integer (current_pc, 2);
+	}
+      else if (insn == ((FP_REGNUM << 11) | 0x0000 | 12)) /* mov r12,r2 */
+	return v850_find_callers_reg (fi, FP_REGNUM); /* It's using a frame pointer reg */
+      else if ((insn & 0x07ff) == (0x0760 | SP_REGNUM))	/* st.w <reg>,<offset>[sp] */
+	current_pc += 2;
+      else if ((insn & 0x07ff) == (0x0760 | FP_REGNUM))	/* st.w <reg>,<offset>[fp] */
+	current_pc += 2;
+    }
+
+  return fi->frame - frameoffset;
+}
+
+CORE_ADDR
+v850_skip_prologue (pc)
+     CORE_ADDR pc;
+{
+  CORE_ADDR func_addr, func_end;
+
+  /* See what the symbol table says */
+
+  if (find_pc_partial_function (pc, NULL, &func_addr, &func_end))
+    {
+      struct symtab_and_line sal;
+
+      sal = find_pc_line (func_addr, 0);
+
+      if (sal.end < func_end)
+	return sal.end;
+      else
+	/* The line after the prologue is after the end of the function.  In
+	   this case, there probably isn't a prologue.  */
+	return pc;
+    }
+
+/* We can't find the start of this function, so there's nothing we can do. */
+  return pc;
+}
+
+struct frame_info *
+v850_pop_frame (frame)
+     struct frame_info *frame;
+{
+  int regnum;
+
+  write_register (PC_REGNUM, FRAME_SAVED_PC (frame));
+
+  for (regnum = 0; regnum < NUM_REGS; regnum++)
+    if (frame->fsr.regs[regnum] != 0)
+      write_register (regnum, read_memory_integer (frame->fsr.regs[regnum], 4));
+
+  write_register (SP_REGNUM, FRAME_FP (frame));
+  flush_cached_frames ();
+
+  return NULL;
+}
 
 void
 _initialize_sparc_tdep ()