This commit was manufactured by cvs2svn to create branch

'kettenis_i386newframe-20030419-branch'.

Cherrypick from master 2003-05-29 23:02:53 UTC Richard Henderson <rth@redhat.com> '	* alpha-linux-tdep.c (alpha_linux_sigtramp_offset_1): New.':
    gdb/alpha-mdebug-tdep.c

1 files changed, 442 insertions, 0 deletions

diff --git a/gdb/alpha-mdebug-tdep.c b/gdb/alpha-mdebug-tdep.c
new file mode 100644
index 0000000..2f84d6d
--- /dev/null
+++ b/gdb/alpha-mdebug-tdep.c
@@ -0,0 +1,442 @@
+/* Target-dependent mdebug code for the ALPHA architecture.
+   Copyright 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003
+   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
+   (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, write to the Free Software
+   Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+#include "defs.h"
+#include "frame.h"
+#include "frame-unwind.h"
+#include "frame-base.h"
+#include "inferior.h"
+#include "symtab.h"
+#include "value.h"
+#include "gdbcmd.h"
+#include "gdbcore.h"
+#include "dis-asm.h"
+#include "symfile.h"
+#include "objfiles.h"
+#include "gdb_string.h"
+#include "linespec.h"
+#include "regcache.h"
+#include "doublest.h"
+#include "arch-utils.h"
+#include "osabi.h"
+#include "block.h"
+#include "gdb_assert.h"
+
+#include "elf-bfd.h"
+
+#include "alpha-tdep.h"
+
+/* FIXME: Some of this code should perhaps be merged with mips.  */
+
+/* *INDENT-OFF* */
+/* Layout of a stack frame on the alpha:
+
+                |				|
+ pdr members:	|  7th ... nth arg,		|
+                |  `pushed' by caller.		|
+                |				|
+----------------|-------------------------------|<--  old_sp == vfp
+   ^  ^  ^  ^	|				|
+   |  |  |  |	|				|
+   |  |localoff	|  Copies of 1st .. 6th		|
+   |  |  |  |	|  argument if necessary.	|
+   |  |  |  v	|				|
+   |  |  |  ---	|-------------------------------|<-- FRAME_LOCALS_ADDRESS
+   |  |  |      |				|
+   |  |  |      |  Locals and temporaries.	|
+   |  |  |      |				|
+   |  |  |      |-------------------------------|
+   |  |  |      |				|
+   |-fregoffset	|  Saved float registers.	|
+   |  |  |      |  F9				|
+   |  |  |      |   .				|
+   |  |  |      |   .				|
+   |  |  |      |  F2				|
+   |  |  v      |				|
+   |  |  -------|-------------------------------|
+   |  |         |				|
+   |  |         |  Saved registers.		|
+   |  |         |  S6				|
+   |-regoffset	|   .				|
+   |  |         |   .				|
+   |  |         |  S0				|
+   |  |         |  pdr.pcreg			|
+   |  v         |				|
+   |  ----------|-------------------------------|
+   |            |				|
+ frameoffset    |  Argument build area, gets	|
+   |            |  7th ... nth arg for any	|
+   |            |  called procedure.		|
+   v            |  				|
+   -------------|-------------------------------|<-- sp
+                |				|
+*/
+/* *INDENT-ON* */
+
+#define PROC_LOW_ADDR(proc) ((proc)->pdr.adr)
+#define PROC_FRAME_OFFSET(proc) ((proc)->pdr.frameoffset)
+#define PROC_FRAME_REG(proc) ((proc)->pdr.framereg)
+#define PROC_REG_MASK(proc) ((proc)->pdr.regmask)
+#define PROC_FREG_MASK(proc) ((proc)->pdr.fregmask)
+#define PROC_REG_OFFSET(proc) ((proc)->pdr.regoffset)
+#define PROC_FREG_OFFSET(proc) ((proc)->pdr.fregoffset)
+#define PROC_PC_REG(proc) ((proc)->pdr.pcreg)
+#define PROC_LOCALOFF(proc) ((proc)->pdr.localoff)
+
+/* Locate the mdebug PDR for the given PC.  Return null if one can't
+   be found; you'll have to fall back to other methods in that case.  */
+
+static alpha_extra_func_info_t
+find_proc_desc (CORE_ADDR pc)
+{
+  struct block *b = block_for_pc (pc);
+  alpha_extra_func_info_t proc_desc = NULL;
+  struct symbol *sym = NULL;
+
+  if (b)
+    {
+      CORE_ADDR startaddr;
+      find_pc_partial_function (pc, NULL, &startaddr, NULL);
+
+      if (startaddr > BLOCK_START (b))
+	/* This is the "pathological" case referred to in a comment in
+	   print_frame_info.  It might be better to move this check into
+	   symbol reading.  */
+	sym = NULL;
+      else
+	sym = lookup_symbol (MIPS_EFI_SYMBOL_NAME, b, LABEL_DOMAIN, 0, NULL);
+    }
+
+  if (sym)
+    {
+      proc_desc = (alpha_extra_func_info_t) SYMBOL_VALUE (sym);
+
+      /* If we never found a PDR for this function in symbol reading,
+	 then examine prologues to find the information.  */
+      if (proc_desc->pdr.framereg == -1)
+	proc_desc = NULL;
+    }
+
+  return proc_desc;
+}
+
+/* This returns the PC of the first inst after the prologue.  If we can't
+   find the prologue, then return 0.  */
+
+static CORE_ADDR
+alpha_mdebug_after_prologue (CORE_ADDR pc, alpha_extra_func_info_t proc_desc)
+{
+  if (proc_desc)
+    {
+      /* If function is frameless, then we need to do it the hard way.  I
+         strongly suspect that frameless always means prologueless... */
+      if (PROC_FRAME_REG (proc_desc) == SP_REGNUM
+	  && PROC_FRAME_OFFSET (proc_desc) == 0)
+	return 0;
+    }
+
+  return alpha_after_prologue (pc);
+}
+
+/* Return non-zero if we *might* be in a function prologue.  Return zero
+   if we are definitively *not* in a function prologue.  */
+
+static int
+alpha_mdebug_in_prologue (CORE_ADDR pc, alpha_extra_func_info_t proc_desc)
+{
+  CORE_ADDR after_prologue_pc = alpha_mdebug_after_prologue (pc, proc_desc);
+  return (after_prologue_pc == 0 || pc < after_prologue_pc);
+}
+
+
+/* Frame unwinder that reads mdebug PDRs.  */
+
+struct alpha_mdebug_unwind_cache
+{
+  alpha_extra_func_info_t proc_desc;
+  CORE_ADDR vfp;
+  CORE_ADDR *saved_regs;
+  void *in_prologue_cache;
+};
+
+/* Extract all of the information about the frame from PROC_DESC
+   and store the resulting register save locations in the structure.  */
+
+static struct alpha_mdebug_unwind_cache *
+alpha_mdebug_frame_unwind_cache (struct frame_info *next_frame, 
+				 void **this_prologue_cache)
+{
+  struct alpha_mdebug_unwind_cache *info;
+  alpha_extra_func_info_t proc_desc;
+  ULONGEST vfp;
+  CORE_ADDR pc, reg_position;
+  unsigned long mask;
+  int ireg, returnreg;
+
+  if (*this_prologue_cache)
+    return *this_prologue_cache;
+
+  info = FRAME_OBSTACK_ZALLOC (struct alpha_mdebug_unwind_cache);
+  *this_prologue_cache = info;
+  pc = frame_pc_unwind (next_frame);
+
+  /* ??? We don't seem to be able to cache the lookup of the PDR
+     from alpha_mdebug_frame_p.  It'd be nice if we could change
+     the arguments to that function.  Oh well.  */
+  proc_desc = find_proc_desc (pc);
+  info->proc_desc = proc_desc;
+  gdb_assert (proc_desc != NULL);
+
+  /* If we're in the prologue, the PDR for this frame is not yet valid.  */
+  /* ??? We could have said "no" in alpha_mdebug_frame_p, and we'd
+     walk down the list of unwinders and try the heuristic unwinder
+     and things would have been fine. However, since we have the PDR,
+     we know how to skip the search for the start of the procedure,
+     and all the uncertainty involved there.  So instead, arrange for
+     us to defer to the heuristic unwinder directly.  */
+  if (alpha_mdebug_in_prologue (pc, proc_desc))
+    {
+      alpha_heuristic_frame_unwind_cache (next_frame,
+      					  &info->in_prologue_cache,
+					  PROC_LOW_ADDR (proc_desc));
+      return info;
+    }
+
+  info->saved_regs = frame_obstack_zalloc (SIZEOF_FRAME_SAVED_REGS);
+
+  /* The VFP of the frame is at FRAME_REG+FRAME_OFFSET.  */
+  frame_unwind_unsigned_register (next_frame, PROC_FRAME_REG (proc_desc), &vfp);
+  vfp += PROC_FRAME_OFFSET (info->proc_desc);
+  info->vfp = vfp;
+
+  /* Fill in the offsets for the registers which gen_mask says were saved.  */
+
+  reg_position = vfp + PROC_REG_OFFSET (proc_desc);
+  mask = PROC_REG_MASK (proc_desc);
+  returnreg = PROC_PC_REG (proc_desc);
+
+  /* Note that RA is always saved first, regardless of its actual
+     register number.  */
+  if (mask & (1 << returnreg))
+    {
+      /* Clear bit for RA so we don't save it again later. */
+      mask &= ~(1 << returnreg);
+
+      info->saved_regs[returnreg] = reg_position;
+      reg_position += 8;
+    }
+
+  for (ireg = 0; ireg <= 31; ++ireg)
+    if (mask & (1 << ireg))
+      {
+	info->saved_regs[ireg] = reg_position;
+	reg_position += 8;
+      }
+
+  reg_position = vfp + PROC_FREG_OFFSET (proc_desc);
+  mask = PROC_FREG_MASK (proc_desc);
+
+  for (ireg = 0; ireg <= 31; ++ireg)
+    if (mask & (1 << ireg))
+      {
+	info->saved_regs[FP0_REGNUM + ireg] = reg_position;
+	reg_position += 8;
+      }
+
+  return info;
+}
+
+/* Given a GDB frame, determine the address of the calling function's
+   frame.  This will be used to create a new GDB frame struct.  */
+
+static void
+alpha_mdebug_frame_this_id (struct frame_info *next_frame,
+			    void **this_prologue_cache,
+			    struct frame_id *this_id)
+{
+  struct alpha_mdebug_unwind_cache *info
+    = alpha_mdebug_frame_unwind_cache (next_frame, this_prologue_cache);
+
+  /* If we're in the prologue, defer to the heuristic unwinder.  */
+  if (info->in_prologue_cache)
+    alpha_heuristic_frame_this_id (next_frame, &info->in_prologue_cache,
+    				   this_id);
+  else
+    *this_id = frame_id_build (info->vfp, frame_func_unwind (next_frame));
+}
+
+/* Retrieve the value of REGNUM in FRAME.  Don't give up!  */
+
+static void
+alpha_mdebug_frame_prev_register (struct frame_info *next_frame,
+				  void **this_prologue_cache,
+				  int regnum, int *optimizedp,
+				  enum lval_type *lvalp, CORE_ADDR *addrp,
+				  int *realnump, void *bufferp)
+{
+  struct alpha_mdebug_unwind_cache *info
+    = alpha_mdebug_frame_unwind_cache (next_frame, this_prologue_cache);
+
+  /* If we're in the prologue, defer to the heuristic unwinder.  */
+  if (info->in_prologue_cache)
+    {
+      alpha_heuristic_frame_prev_register (next_frame,
+      					   &info->in_prologue_cache,
+					   regnum, optimizedp, lvalp,
+					   addrp, realnump, bufferp);
+      return;
+    }
+
+  /* The PC of the previous frame is stored in the link register of
+     the current frame.  Frob regnum so that we pull the value from
+     the correct place.  */
+  if (regnum == PC_REGNUM)
+    regnum = PROC_PC_REG (info->proc_desc);
+  
+  /* For all registers known to be saved in the current frame, 
+     do the obvious and pull the value out.  */
+  if (info->saved_regs[regnum])
+    {
+      *optimizedp = 0;
+      *lvalp = lval_memory;
+      *addrp = info->saved_regs[regnum];
+      *realnump = -1;
+      if (bufferp != NULL)
+	read_memory (*addrp, bufferp, ALPHA_REGISTER_SIZE);
+      return;
+    }
+
+  /* The stack pointer of the previous frame is computed by popping
+     the current stack frame.  */
+  if (regnum == SP_REGNUM)
+    {
+      *optimizedp = 0;
+      *lvalp = not_lval;
+      *addrp = 0;
+      *realnump = -1;
+      if (bufferp != NULL)
+	store_unsigned_integer (bufferp, ALPHA_REGISTER_SIZE, info->vfp);
+      return;
+    }
+
+  /* Otherwise assume the next frame has the same register value.  */
+  frame_register (next_frame, regnum, optimizedp, lvalp, addrp,
+  		  realnump, bufferp);
+}
+
+static const struct frame_unwind alpha_mdebug_frame_unwind = {
+  NORMAL_FRAME,
+  alpha_mdebug_frame_this_id,
+  alpha_mdebug_frame_prev_register
+};
+
+const struct frame_unwind *
+alpha_mdebug_frame_p (CORE_ADDR pc)
+{
+  alpha_extra_func_info_t proc_desc;
+
+  /* If this PC does not map to a PDR, then clearly this isn't an
+     mdebug frame.  */
+  proc_desc = find_proc_desc (pc);
+  if (proc_desc == NULL)
+    return NULL;
+
+  return &alpha_mdebug_frame_unwind;
+}
+
+static CORE_ADDR
+alpha_mdebug_frame_base_address (struct frame_info *next_frame,
+				 void **this_prologue_cache)
+{
+  struct alpha_mdebug_unwind_cache *info
+    = alpha_mdebug_frame_unwind_cache (next_frame, this_prologue_cache);
+
+  if (info->in_prologue_cache)
+    return alpha_heuristic_frame_base_address (next_frame,
+    					       &info->in_prologue_cache);
+  else
+    return info->vfp;
+}
+
+static CORE_ADDR
+alpha_mdebug_frame_locals_address (struct frame_info *next_frame,
+				   void **this_prologue_cache)
+{
+  struct alpha_mdebug_unwind_cache *info
+    = alpha_mdebug_frame_unwind_cache (next_frame, this_prologue_cache);
+  CORE_ADDR vfp;
+
+  if (info->in_prologue_cache)
+    vfp = alpha_heuristic_frame_base_address (next_frame,
+    					      &info->in_prologue_cache);
+  else
+    vfp = info->vfp;
+
+  return vfp - PROC_LOCALOFF (info->proc_desc);
+}
+
+static CORE_ADDR
+alpha_mdebug_frame_args_address (struct frame_info *next_frame,
+				 void **this_prologue_cache)
+{
+  struct alpha_mdebug_unwind_cache *info
+    = alpha_mdebug_frame_unwind_cache (next_frame, this_prologue_cache);
+  CORE_ADDR vfp;
+
+  if (info->in_prologue_cache)
+    vfp = alpha_heuristic_frame_base_address (next_frame,
+    					      &info->in_prologue_cache);
+  else
+    vfp = info->vfp;
+
+  return vfp - ALPHA_NUM_ARG_REGS * 8;
+}
+
+static const struct frame_base alpha_mdebug_frame_base = {
+  &alpha_mdebug_frame_unwind,
+  alpha_mdebug_frame_base_address,
+  alpha_mdebug_frame_locals_address,
+  alpha_mdebug_frame_args_address
+};
+
+static const struct frame_base *
+alpha_mdebug_frame_base_p (CORE_ADDR pc)
+{
+  alpha_extra_func_info_t proc_desc;
+
+  /* If this PC does not map to a PDR, then clearly this isn't an
+     mdebug frame.  */
+  proc_desc = find_proc_desc (pc);
+  if (proc_desc == NULL)
+    return NULL;
+
+  return &alpha_mdebug_frame_base;
+}
+
+
+void
+alpha_mdebug_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
+{
+  struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
+
+  frame_unwind_append_predicate (gdbarch, alpha_mdebug_frame_p);
+  frame_base_append_predicate (gdbarch, alpha_mdebug_frame_base_p);
+}