[pf3gnuchains/gcc-fork.git] / gcc / integrate.c

/* Procedure integration for GNU CC.
   Copyright (C) 1988-1991 Free Software Foundation, Inc.
   Contributed by Michael Tiemann (tiemann@cygnus.com)

This file is part of GNU CC.

GNU CC 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, or (at your option)
any later version.

GNU CC 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 GNU CC; see the file COPYING.  If not, write to
the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.  */


#include <stdio.h>

#include "config.h"
#include "rtl.h"
#include "tree.h"
#include "flags.h"
#include "insn-config.h"
#include "insn-flags.h"
#include "expr.h"
#include "output.h"
#include "integrate.h"
#include "real.h"
#include "function.h"

#include "obstack.h"
#define obstack_chunk_alloc     xmalloc
#define obstack_chunk_free      free
extern int xmalloc ();
extern void free ();

extern struct obstack *function_maybepermanent_obstack;

extern tree pushdecl ();
extern tree poplevel ();

/* Similar, but round to the next highest integer that meets the
   alignment.  */
#define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))

/* Default max number of insns a function can have and still be inline.
   This is overridden on RISC machines.  */
#ifndef INTEGRATE_THRESHOLD
#define INTEGRATE_THRESHOLD(DECL) \
  (8 * (8 + list_length (DECL_ARGUMENTS (DECL))))
#endif
\f
/* Save any constant pool constants in an insn.  */
static void save_constants ();

/* Note when parameter registers are the destination of a SET.  */
static void note_modified_parmregs ();

/* Copy an rtx for save_for_inline_copying.  */
static rtx copy_for_inline ();

/* Make copies of MEMs in DECL_RTLs.  */
static void copy_decl_rtls ();

static tree copy_decl_tree ();

/* Return the constant equivalent of a given rtx, or 0 if none.  */
static rtx const_equiv ();

static void integrate_parm_decls ();
static void integrate_decl_tree ();

static void subst_constants ();
static rtx fold_out_const_cc0 ();
\f
/* Zero if the current function (whose FUNCTION_DECL is FNDECL)
   is safe and reasonable to integrate into other functions.
   Nonzero means value is a warning message with a single %s
   for the function's name.  */

char *
function_cannot_inline_p (fndecl)
     register tree fndecl;
{
  register rtx insn;
  tree last = tree_last (TYPE_ARG_TYPES (TREE_TYPE (fndecl)));
  int max_insns = INTEGRATE_THRESHOLD (fndecl);
  register int ninsns = 0;
  register tree parms;

  /* No inlines with varargs.  `grokdeclarator' gives a warning
     message about that if `inline' is specified.  This code
     it put in to catch the volunteers.  */
  if ((last && TREE_VALUE (last) != void_type_node)
      || (DECL_ARGUMENTS (fndecl) && DECL_NAME (DECL_ARGUMENTS (fndecl))
          && ! strcmp (IDENTIFIER_POINTER (DECL_NAME (DECL_ARGUMENTS (fndecl))),
                       "__builtin_va_alist")))
    return "varargs function cannot be inline";

  if (current_function_calls_alloca)
    return "function using alloca cannot be inline";

  if (current_function_contains_functions)
    return "function with nested functions cannot be inline";

  /* This restriction may be eliminated sometime soon.  But for now, don't
     worry about remapping the static chain.  */
  if (current_function_needs_context)
    return "nested function cannot be inline";

  /* If its not even close, don't even look.  */
  if (!TREE_INLINE (fndecl) && get_max_uid () > 3 * max_insns)
    return "function too large to be inline";

#if 0
  /* Large stacks are OK now that inlined functions can share them.  */
  /* Don't inline functions with large stack usage,
     since they can make other recursive functions burn up stack.  */
  if (!TREE_INLINE (fndecl) && get_frame_size () > 100)
    return "function stack frame for inlining";
#endif

#if 0
  /* Don't inline functions which do not specify a function prototype and
     have BLKmode argument or take the address of a parameter.  */
  for (parms = DECL_ARGUMENTS (fndecl); parms; parms = TREE_CHAIN (parms))
    {
      if (TYPE_MODE (TREE_TYPE (parms)) == BLKmode)
        TREE_ADDRESSABLE (parms) = 1;
      if (last == NULL_TREE && TREE_ADDRESSABLE (parms))
        return "no prototype, and parameter address used; cannot be inline";
    }
#endif

  /* We can't inline functions that return structures
     the old-fashioned PCC way, copying into a static block.  */
  if (current_function_returns_pcc_struct)
    return "inline functions not supported for this return value type";

  /* We can't inline functions that return structures of varying size.  */
  if (int_size_in_bytes (TREE_TYPE (TREE_TYPE (fndecl))) < 0)
    return "function with varying-size return value cannot be inline";

  /* Cannot inline a function with a varying size argument.  */
  for (parms = DECL_ARGUMENTS (fndecl); parms; parms = TREE_CHAIN (parms))
    if (int_size_in_bytes (TREE_TYPE (parms)) < 0)
      return "function with varying-size parameter cannot be inline";

  if (!TREE_INLINE (fndecl) && get_max_uid () > max_insns)
    {
      for (ninsns = 0, insn = get_first_nonparm_insn (); insn && ninsns < max_insns;
           insn = NEXT_INSN (insn))
        {
          if (GET_RTX_CLASS (GET_CODE (insn)) == 'i')
            ninsns++;
        }

      if (ninsns >= max_insns)
        return "function too large to be inline";
    }

  return 0;
}
\f
/* Variables used within save_for_inline.  */

/* Mapping from old pseudo-register to new pseudo-registers.
   The first element of this map is reg_map[FIRST_PSEUDO_REGISTER].
   It is allocated in `save_for_inline' and `expand_inline_function',
   and deallocated on exit from each of those routines.  */
static rtx *reg_map;

/* Mapping from old code-labels to new code-labels.
   The first element of this map is label_map[min_labelno].
   It is allocated in `save_for_inline' and `expand_inline_function',
   and deallocated on exit from each of those routines.  */
static rtx *label_map;

/* Mapping from old insn uid's to copied insns.
   It is allocated in `save_for_inline' and `expand_inline_function',
   and deallocated on exit from each of those routines.  */
static rtx *insn_map;

/* Map pseudo reg number into the PARM_DECL for the parm living in the reg.
   Zero for a reg that isn't a parm's home.
   Only reg numbers less than max_parm_reg are mapped here.  */
static tree *parmdecl_map;

/* Keep track of first pseudo-register beyond those that are parms.  */
static int max_parm_reg;

/* When an insn is being copied by copy_for_inline,
   this is nonzero if we have copied an ASM_OPERANDS.
   In that case, it is the original input-operand vector.  */
static rtvec orig_asm_operands_vector;

/* When an insn is being copied by copy_for_inline,
   this is nonzero if we have copied an ASM_OPERANDS.
   In that case, it is the copied input-operand vector.  */
static rtvec copy_asm_operands_vector;

/* Likewise, this is the copied constraints vector.  */
static rtvec copy_asm_constraints_vector;

/* In save_for_inline, nonzero if past the parm-initialization insns.  */
static int in_nonparm_insns;
\f
/* Subroutine for `save_for_inline{copying,nocopy}'.  Performs initialization
   needed to save FNDECL's insns and info for future inline expansion.  */
   
static rtx
initialize_for_inline (fndecl, min_labelno, max_labelno, max_reg, copy)
     tree fndecl;
     int min_labelno;
     int max_labelno;
     int max_reg;
     int copy;
{
  int function_flags, i;
  rtvec arg_vector;
  tree parms;

  /* Compute the values of any flags we must restore when inlining this.  */

  function_flags
    = (current_function_calls_alloca * FUNCTION_FLAGS_CALLS_ALLOCA
       + current_function_calls_setjmp * FUNCTION_FLAGS_CALLS_SETJMP
       + current_function_calls_longjmp * FUNCTION_FLAGS_CALLS_LONGJMP
       + current_function_returns_struct * FUNCTION_FLAGS_RETURNS_STRUCT
       + current_function_returns_pcc_struct * FUNCTION_FLAGS_RETURNS_PCC_STRUCT
       + current_function_needs_context * FUNCTION_FLAGS_NEEDS_CONTEXT
       + current_function_has_nonlocal_label * FUNCTION_FLAGS_HAS_NONLOCAL_LABEL
       + current_function_returns_pointer * FUNCTION_FLAGS_RETURNS_POINTER
       + current_function_uses_const_pool * FUNCTION_FLAGS_USES_CONST_POOL
       + current_function_uses_pic_offset_table * FUNCTION_FLAGS_USES_PIC_OFFSET_TABLE);

  /* Clear out PARMDECL_MAP.  It was allocated in the caller's frame.  */
  bzero (parmdecl_map, max_parm_reg * sizeof (tree));
  arg_vector = rtvec_alloc (list_length (DECL_ARGUMENTS (fndecl)));

  for (parms = DECL_ARGUMENTS (fndecl), i = 0;
       parms;
       parms = TREE_CHAIN (parms), i++)
    {
      rtx p = DECL_RTL (parms);

      if (GET_CODE (p) == MEM && copy)
        /* Copy the rtl so that modifications of the address
           later in compilation won't affect this arg_vector.
           Virtual register instantiation can screw the address
           of the rtl.  */
        DECL_RTL (parms) = copy_rtx (p);

      RTVEC_ELT (arg_vector, i) = p;

      if (GET_CODE (p) == REG)
        parmdecl_map[REGNO (p)] = parms;
      TREE_READONLY (parms) = 1;
    }

  /* Assume we start out in the insns that set up the parameters.  */
  in_nonparm_insns = 0;

  /* The list of DECL_SAVED_INSNS, starts off with a header which
     contains the following information:

     the first insn of the function (not including the insns that copy
     parameters into registers).
     the first parameter insn of the function,
     the first label used by that function,
     the last label used by that function,
     the highest register number used for parameters,
     the total number of registers used,
     the size of the incoming stack area for parameters,
     the number of bytes popped on return,
     the stack slot list,
     some flags that are used to restore compiler globals,
     the value of current_function_outgoing_args_size,
     the original argument vector,
     and the original DECL_INITIAL.  */

  return gen_inline_header_rtx (NULL, NULL, min_labelno, max_labelno,
                                max_parm_reg, max_reg,
                                current_function_args_size,
                                current_function_pops_args,
                                stack_slot_list, function_flags,
                                current_function_outgoing_args_size,
                                arg_vector, (rtx) DECL_INITIAL (fndecl));
}

/* Subroutine for `save_for_inline{copying,nocopy}'.  Finishes up the
   things that must be done to make FNDECL expandable as an inline function.
   HEAD contains the chain of insns to which FNDECL will expand.  */
   
static void
finish_inline (fndecl, head)
     tree fndecl;
     rtx head;
{
  NEXT_INSN (head) = get_first_nonparm_insn ();
  FIRST_PARM_INSN (head) = get_insns ();
  DECL_SAVED_INSNS (fndecl) = head;
  DECL_FRAME_SIZE (fndecl) = get_frame_size ();
  TREE_INLINE (fndecl) = 1;
}

/* Make the insns and PARM_DECLs of the current function permanent
   and record other information in DECL_SAVED_INSNS to allow inlining
   of this function in subsequent calls.

   This function is called when we are going to immediately compile
   the insns for FNDECL.  The insns in maybepermanent_obstack cannot be
   modified by the compilation process, so we copy all of them to
   new storage and consider the new insns to be the insn chain to be
   compiled.  */

void
save_for_inline_copying (fndecl)
     tree fndecl;
{
  rtx first_insn, last_insn, insn;
  rtx head, copy;
  int max_labelno, min_labelno, i, len;
  int max_reg;
  int max_uid;
  rtx first_nonparm_insn;

  /* Make and emit a return-label if we have not already done so. 
     Do this before recording the bounds on label numbers. */

  if (return_label == 0)
    {
      return_label = gen_label_rtx ();
      emit_label (return_label);
    }

  /* Get some bounds on the labels and registers used.  */

  max_labelno = max_label_num ();
  min_labelno = get_first_label_num ();
  max_reg = max_reg_num ();

  /* Set up PARMDECL_MAP which maps pseudo-reg number to its PARM_DECL.
     Later we set TREE_READONLY to 0 if the parm is modified inside the fn.
     Also set up ARG_VECTOR, which holds the unmodified DECL_RTX values
     for the parms, prior to elimination of virtual registers.
     These values are needed for substituting parms properly.  */

  max_parm_reg = max_parm_reg_num ();
  parmdecl_map = (tree *) alloca (max_parm_reg * sizeof (tree));

  head = initialize_for_inline (fndecl, min_labelno, max_labelno, max_reg, 1);

  if (current_function_uses_const_pool)
    {
      /* Replace any constant pool references with the actual constant.  We
         will put the constants back in the copy made below.  */
      for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
        if (GET_RTX_CLASS (GET_CODE (insn)) == 'i')
          {
            save_constants (&PATTERN (insn));
            if (REG_NOTES (insn))
              save_constants (&REG_NOTES (insn));
          }

      /* Clear out the constant pool so that we can recreate it with the
         copied constants below.  */
      init_const_rtx_hash_table ();
      clear_const_double_mem ();
    }

  max_uid = INSN_UID (head);

  /* We have now allocated all that needs to be allocated permanently
     on the rtx obstack.  Set our high-water mark, so that we
     can free the rest of this when the time comes.  */

  preserve_data ();

  /* Copy the chain insns of this function.
     Install the copied chain as the insns of this function,
     for continued compilation;
     the original chain is recorded as the DECL_SAVED_INSNS
     for inlining future calls.  */

  /* If there are insns that copy parms from the stack into pseudo registers,
     those insns are not copied.  `expand_inline_function' must
     emit the correct code to handle such things.  */

  insn = get_insns ();
  if (GET_CODE (insn) != NOTE)
    abort ();
  first_insn = rtx_alloc (NOTE);
  NOTE_SOURCE_FILE (first_insn) = NOTE_SOURCE_FILE (insn);
  NOTE_LINE_NUMBER (first_insn) = NOTE_LINE_NUMBER (insn);
  INSN_UID (first_insn) = INSN_UID (insn);
  PREV_INSN (first_insn) = NULL;
  NEXT_INSN (first_insn) = NULL;
  last_insn = first_insn;

  /* Each pseudo-reg in the old insn chain must have a unique rtx in the copy.
     Make these new rtx's now, and install them in regno_reg_rtx, so they
     will be the official pseudo-reg rtx's for the rest of compilation.  */

  reg_map = (rtx *) alloca ((max_reg + 1) * sizeof (rtx));

  len = sizeof (struct rtx_def) + (GET_RTX_LENGTH (REG) - 1) * sizeof (rtunion);
  for (i = max_reg - 1; i > LAST_VIRTUAL_REGISTER; i--)
    reg_map[i] = (rtx)obstack_copy (function_maybepermanent_obstack,
                                    regno_reg_rtx[i], len);

  bcopy (reg_map + LAST_VIRTUAL_REGISTER + 1,
         regno_reg_rtx + LAST_VIRTUAL_REGISTER + 1,
         (max_reg - (LAST_VIRTUAL_REGISTER + 1)) * sizeof (rtx));

  /* Likewise each label rtx must have a unique rtx as its copy.  */

  label_map = (rtx *)alloca ((max_labelno - min_labelno) * sizeof (rtx));
  label_map -= min_labelno;

  for (i = min_labelno; i < max_labelno; i++)
    label_map[i] = gen_label_rtx ();

  /* Record the mapping of old insns to copied insns.  */

  insn_map = (rtx *) alloca (max_uid * sizeof (rtx));
  bzero (insn_map, max_uid * sizeof (rtx));

  /* Get the insn which signals the end of parameter setup code.  */
  first_nonparm_insn = get_first_nonparm_insn ();

  /* Copy any entries in regno_reg_rtx or DECL_RTLs that reference MEM
     (the former occurs when a variable has its address taken)
     since these may be shared and can be changed by virtual
     register instantiation.  DECL_RTL values for our arguments
     have already been copied by initialize_for_inline.  */
  for (i = LAST_VIRTUAL_REGISTER + 1; i < max_reg; i++)
    if (GET_CODE (regno_reg_rtx[i]) == MEM)
      XEXP (regno_reg_rtx[i], 0)
        = copy_for_inline (XEXP (regno_reg_rtx[i], 0));

  /* Copy the tree of subblocks of the function, and the decls in them.
     We will use the copy for compiling this function, then restore the original
     subblocks and decls for use when inlining this function.

     Several parts of the compiler modify BLOCK trees.  In particular,
     instantiate_virtual_regs will instantiate any virtual regs
     mentioned in the DECL_RTLs of the decls, and loop
     unrolling will replicate any BLOCK trees inside an unrolled loop.

     The modified subblocks or DECL_RTLs would be incorrect for the original rtl
     which we will use for inlining.  The rtl might even contain pseudoregs
     whose space has been freed.  */

  DECL_INITIAL (fndecl) = copy_decl_tree (DECL_INITIAL (fndecl));

  /* Now copy each DECL_RTL which is a MEM,
     so it is safe to modify their addresses.  */
  copy_decl_rtls (DECL_INITIAL (fndecl));

  /* Now copy the chain of insns.  Do this twice.  The first copy the insn
     itself and its body.  The second time copy of REG_NOTES.  This is because
     a REG_NOTE may have a forward pointer to another insn.  */

  for (insn = NEXT_INSN (insn); insn; insn = NEXT_INSN (insn))
    {
      orig_asm_operands_vector = 0;

      if (insn == first_nonparm_insn)
        in_nonparm_insns = 1;

      switch (GET_CODE (insn))
        {
        case NOTE:
          /* No need to keep these.  */
          if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_DELETED)
            continue;

          copy = rtx_alloc (NOTE);
          NOTE_SOURCE_FILE (copy) = NOTE_SOURCE_FILE (insn);
          NOTE_LINE_NUMBER (copy) = NOTE_LINE_NUMBER (insn);
          break;

        case INSN:
        case CALL_INSN:
        case JUMP_INSN:
          copy = rtx_alloc (GET_CODE (insn));
          PATTERN (copy) = copy_for_inline (PATTERN (insn));
          INSN_CODE (copy) = -1;
          LOG_LINKS (copy) = NULL;
          RTX_INTEGRATED_P (copy) = RTX_INTEGRATED_P (insn);
          break;

        case CODE_LABEL:
          copy = label_map[CODE_LABEL_NUMBER (insn)];
          break;

        case BARRIER:
          copy = rtx_alloc (BARRIER);
          break;

        default:
          abort ();
        }
      INSN_UID (copy) = INSN_UID (insn);
      insn_map[INSN_UID (insn)] = copy;
      NEXT_INSN (last_insn) = copy;
      PREV_INSN (copy) = last_insn;
      last_insn = copy;
    }

  /* Now copy the REG_NOTES.  */
  for (insn = NEXT_INSN (get_insns ()); insn; insn = NEXT_INSN (insn))
    if (GET_RTX_CLASS (GET_CODE (insn)) == 'i'
        && insn_map[INSN_UID(insn)])
      REG_NOTES (insn_map[INSN_UID (insn)])
        = copy_for_inline (REG_NOTES (insn));

  NEXT_INSN (last_insn) = NULL;

  finish_inline (fndecl, head);

  set_new_first_and_last_insn (first_insn, last_insn);
}

/* Make a copy of the entire tree of blocks BLOCK, and return it.  */

static tree
copy_decl_tree (block)
     tree block;
{
  tree t, vars, subblocks;

  vars = copy_list (BLOCK_VARS (block));
  subblocks = 0;

  /* Process all subblocks.  */
  for (t = BLOCK_SUBBLOCKS (block); t; t = TREE_CHAIN (t))
    {
      tree copy = copy_decl_tree (t);
      TREE_CHAIN (copy) = subblocks;
      subblocks = copy;
    }

  t = copy_node (block);
  BLOCK_VARS (t) = vars;
  BLOCK_SUBBLOCKS (t) = nreverse (subblocks);
  return t;
}

/* Copy DECL_RTLs in all decls in the given BLOCK node.  */

static void
copy_decl_rtls (block)
     tree block;
{
  tree t;

  for (t = BLOCK_VARS (block); t; t = TREE_CHAIN (t))
    if (DECL_RTL (t) && GET_CODE (DECL_RTL (t)) == MEM)
      DECL_RTL (t) = copy_for_inline (DECL_RTL (t));

  /* Process all subblocks.  */
  for (t = BLOCK_SUBBLOCKS (block); t; t = TREE_CHAIN (t))
    copy_decl_rtls (t);
}

/* Make the insns and PARM_DECLs of the current function permanent
   and record other information in DECL_SAVED_INSNS to allow inlining
   of this function in subsequent calls.

   This routine need not copy any insns because we are not going
   to immediately compile the insns in the insn chain.  There
   are two cases when we would compile the insns for FNDECL:
   (1) when FNDECL is expanded inline, and (2) when FNDECL needs to
   be output at the end of other compilation, because somebody took
   its address.  In the first case, the insns of FNDECL are copied
   as it is expanded inline, so FNDECL's saved insns are not
   modified.  In the second case, FNDECL is used for the last time,
   so modifying the rtl is not a problem.

   ??? Actually, we do not verify that FNDECL is not inline expanded
   by other functions which must also be written down at the end
   of compilation.  We could set flag_no_inline to nonzero when
   the time comes to write down such functions.  */

void
save_for_inline_nocopy (fndecl)
     tree fndecl;
{
  rtx insn;
  rtx head, copy;
  tree parms;
  int max_labelno, min_labelno, i, len;
  int max_reg;
  int max_uid;
  rtx first_nonparm_insn;
  int function_flags;

  /* Set up PARMDECL_MAP which maps pseudo-reg number to its PARM_DECL.
     Later we set TREE_READONLY to 0 if the parm is modified inside the fn.
     Also set up ARG_VECTOR, which holds the unmodified DECL_RTX values
     for the parms, prior to elimination of virtual registers.
     These values are needed for substituting parms properly.  */

  max_parm_reg = max_parm_reg_num ();
  parmdecl_map = (tree *) alloca (max_parm_reg * sizeof (tree));

  /* Make and emit a return-label if we have not already done so.  */

  if (return_label == 0)
    {
      return_label = gen_label_rtx ();
      emit_label (return_label);
    }

  head = initialize_for_inline (fndecl, get_first_label_num (),
                                max_label_num (), max_reg_num (), 0);

  /* If there are insns that copy parms from the stack into pseudo registers,
     those insns are not copied.  `expand_inline_function' must
     emit the correct code to handle such things.  */

  insn = get_insns ();
  if (GET_CODE (insn) != NOTE)
    abort ();

  /* Get the insn which signals the end of parameter setup code.  */
  first_nonparm_insn = get_first_nonparm_insn ();

  /* Now just scan the chain of insns to see what happens to our
     PARM_DECLs.  If a PARM_DECL is used but never modified, we
     can substitute its rtl directly when expanding inline (and
     perform constant folding when its incoming value is constant).
     Otherwise, we have to copy its value into a new register and track
     the new register's life.  */

  for (insn = NEXT_INSN (insn); insn; insn = NEXT_INSN (insn))
    {
      if (insn == first_nonparm_insn)
        in_nonparm_insns = 1;

      if (GET_RTX_CLASS (GET_CODE (insn)) == 'i')
        {
          if (current_function_uses_const_pool)
            {
              /* Replace any constant pool references with the actual constant.
                 We will put the constant back if we need to write the
                 function out after all.  */
              save_constants (&PATTERN (insn));
              if (REG_NOTES (insn))
                save_constants (&REG_NOTES (insn));
            }

          /* Record what interesting things happen to our parameters.  */
          note_stores (PATTERN (insn), note_modified_parmregs);
        }
    }

  /* We have now allocated all that needs to be allocated permanently
     on the rtx obstack.  Set our high-water mark, so that we
     can free the rest of this when the time comes.  */

  preserve_data ();

  finish_inline (fndecl, head);
}
\f
/* Given PX, a pointer into an insn, search for references to the constant
   pool.  Replace each with a CONST that has the mode of the original
   constant, contains the constant, and has RTX_INTEGRATED_P set.
   Similarly, constant pool addresses not enclosed in a MEM are replaced
   with an ADDRESS rtx which also gives the constant, mode, and has
   RTX_INTEGRATED_P set.  */

static void
save_constants (px)
     rtx *px;
{
  rtx x;
  int i, j;

 again:
  x = *px;

  /* If this is a CONST_DOUBLE, don't try to fix things up in 
     CONST_DOUBLE_MEM, because this is an infinite recursion.  */
  if (GET_CODE (x) == CONST_DOUBLE)
    return;
  else if (GET_CODE (x) == MEM && GET_CODE (XEXP (x, 0)) == SYMBOL_REF
           && CONSTANT_POOL_ADDRESS_P (XEXP (x,0)))
    {
      enum machine_mode const_mode = get_pool_mode (XEXP (x, 0));
      rtx new = gen_rtx (CONST, const_mode, get_pool_constant (XEXP (x, 0)));
      RTX_INTEGRATED_P (new) = 1;

      /* If the MEM was in a different mode than the constant (perhaps we
         were only looking at the low-order part), surround it with a 
         SUBREG so we can save both modes.  */

      if (GET_MODE (x) != const_mode)
        {
          new = gen_rtx (SUBREG, GET_MODE (x), new, 0);
          RTX_INTEGRATED_P (new) = 1;
        }

      *px = new;
      save_constants (&XEXP (*px, 0));
    }
  else if (GET_CODE (x) == SYMBOL_REF
           && CONSTANT_POOL_ADDRESS_P (x))
    {
      *px = gen_rtx (ADDRESS, get_pool_mode (x), get_pool_constant (x));
      save_constants (&XEXP (*px, 0));
      RTX_INTEGRATED_P (*px) = 1;
    }

  else
    {
      char *fmt = GET_RTX_FORMAT (GET_CODE (x));
      int len = GET_RTX_LENGTH (GET_CODE (x));

      for (i = len-1; i >= 0; i--)
        {
          switch (fmt[i])
            {
            case 'E':
              for (j = 0; j < XVECLEN (x, i); j++)
                save_constants (&XVECEXP (x, i, j));
              break;

            case 'e':
              if (XEXP (x, i) == 0)
                continue;
              if (i == 0)
                {
                  /* Hack tail-recursion here.  */
                  px = &XEXP (x, 0);
                  goto again;
                }
              save_constants (&XEXP (x, i));
              break;
            }
        }
    }
}
\f
/* Note whether a parameter is modified or not.  */

static void
note_modified_parmregs (reg, x)
     rtx reg;
     rtx x;
{
  if (GET_CODE (reg) == REG && in_nonparm_insns
      && REGNO (reg) < max_parm_reg
      && REGNO (reg) >= FIRST_PSEUDO_REGISTER
      && parmdecl_map[REGNO (reg)] != 0)
    TREE_READONLY (parmdecl_map[REGNO (reg)]) = 0;
}

/* Copy the rtx ORIG recursively, replacing pseudo-regs and labels
   according to `reg_map' and `label_map'.  The original rtl insns
   will be saved for inlining; this is used to make a copy
   which is used to finish compiling the inline function itself.

   If we find a "saved" constant pool entry, one which was replaced with
   the value of the constant, convert it back to a constant pool entry.
   Since the pool wasn't touched, this should simply restore the old
   address.

   All other kinds of rtx are copied except those that can never be
   changed during compilation.  */

static rtx
copy_for_inline (orig)
     rtx orig;
{
  register rtx x = orig;
  register int i;
  register enum rtx_code code;
  register char *format_ptr;

  if (x == 0)
    return x;

  code = GET_CODE (x);

  /* These types may be freely shared.  */

  switch (code)
    {
    case QUEUED:
    case CONST_INT:
    case SYMBOL_REF:
    case PC:
    case CC0:
      return x;

    case CONST_DOUBLE:
      /* We have to make a new CONST_DOUBLE to ensure that we account for
         it correctly.  Using the old CONST_DOUBLE_MEM data is wrong.  */
      if (GET_MODE_CLASS (GET_MODE (x)) == MODE_FLOAT)
        {
          REAL_VALUE_TYPE d;

          REAL_VALUE_FROM_CONST_DOUBLE (d, x);
          return immed_real_const_1 (d, GET_MODE (x));
        }
      else
        return immed_double_const (CONST_DOUBLE_LOW (x), CONST_DOUBLE_HIGH (x),
                                   VOIDmode);

    case CONST:
      /* Get constant pool entry for constant in the pool.  */
      if (RTX_INTEGRATED_P (x))
        return validize_mem (force_const_mem (GET_MODE (x),
                                              copy_for_inline (XEXP (x, 0))));
      break;

    case SUBREG:
      /* Get constant pool entry, but access in different mode.  */
      if (RTX_INTEGRATED_P (x))
        {
          rtx new
            = force_const_mem (GET_MODE (SUBREG_REG (x)),
                               copy_for_inline (XEXP (SUBREG_REG (x), 0)));

          PUT_MODE (new, GET_MODE (x));
          return validize_mem (new);
        }
      break;

    case ADDRESS:
      /* If not special for constant pool error.  Else get constant pool
         address.  */
      if (! RTX_INTEGRATED_P (x))
        abort ();

      return XEXP (force_const_mem (GET_MODE (x),
                                    copy_for_inline (XEXP (x, 0))), 0);

    case ASM_OPERANDS:
      /* If a single asm insn contains multiple output operands
         then it contains multiple ASM_OPERANDS rtx's that share operand 3.
         We must make sure that the copied insn continues to share it.  */
      if (orig_asm_operands_vector == XVEC (orig, 3))
        {
          x = rtx_alloc (ASM_OPERANDS);
          XSTR (x, 0) = XSTR (orig, 0);
          XSTR (x, 1) = XSTR (orig, 1);
          XINT (x, 2) = XINT (orig, 2);
          XVEC (x, 3) = copy_asm_operands_vector;
          XVEC (x, 4) = copy_asm_constraints_vector;
          XSTR (x, 5) = XSTR (orig, 5);
          XINT (x, 6) = XINT (orig, 6);
          return x;
        }
      break;

    case MEM:
      /* A MEM is usually allowed to be shared if its address is constant
         or is a constant plus one of the special registers.

         We do not allow sharing of addresses that are either a special
         register or the sum of a constant and a special register because
         it is possible for unshare_all_rtl to copy the address, into memory
         that won't be saved.  Although the MEM can safely be shared, and
         won't be copied there, the address itself cannot be shared, and may
         need to be copied. 

         There are also two exceptions with constants: The first is if the
         constant is a LABEL_REF or the sum of the LABEL_REF
         and an integer.  This case can happen if we have an inline
         function that supplies a constant operand to the call of another
         inline function that uses it in a switch statement.  In this case,
         we will be replacing the LABEL_REF, so we have to replace this MEM
         as well.

         The second case is if we have a (const (plus (address ..) ...)).
         In that case we need to put back the address of the constant pool
         entry.  */

      if (CONSTANT_ADDRESS_P (XEXP (x, 0))
          && GET_CODE (XEXP (x, 0)) != LABEL_REF
          && ! (GET_CODE (XEXP (x, 0)) == CONST
                && (GET_CODE (XEXP (XEXP (x, 0), 0)) == PLUS
                    && ((GET_CODE (XEXP (XEXP (XEXP (x, 0), 0), 0))
                        == LABEL_REF)
                        || (GET_CODE (XEXP (XEXP (XEXP (x, 0), 0), 0))
                            == ADDRESS)))))
        return x;
      break;

    case LABEL_REF:
      {
        /* Must point to the new insn.  */
        return gen_rtx (LABEL_REF, GET_MODE (orig),
                        label_map[CODE_LABEL_NUMBER (XEXP (orig, 0))]);
      }

    case REG:
      if (REGNO (x) > LAST_VIRTUAL_REGISTER)
        return reg_map [REGNO (x)];
      else
        return x;

    case SET:
      /* If a parm that gets modified lives in a pseudo-reg,
         clear its TREE_READONLY to prevent certain optimizations.  */
      {
        rtx dest = SET_DEST (x);

        while (GET_CODE (dest) == STRICT_LOW_PART
               || GET_CODE (dest) == ZERO_EXTRACT
               || GET_CODE (dest) == SUBREG)
          dest = XEXP (dest, 0);

        if (GET_CODE (dest) == REG
            && REGNO (dest) < max_parm_reg
            && REGNO (dest) >= FIRST_PSEUDO_REGISTER
            && parmdecl_map[REGNO (dest)] != 0
            /* The insn to load an arg pseudo from a stack slot
               does not count as modifying it.  */
            && in_nonparm_insns)
          TREE_READONLY (parmdecl_map[REGNO (dest)]) = 0;
      }
      break;

#if 0 /* This is a good idea, but here is the wrong place for it.  */
      /* Arrange that CONST_INTs always appear as the second operand
         if they appear, and that `frame_pointer_rtx' or `arg_pointer_rtx'
         always appear as the first.  */
    case PLUS:
      if (GET_CODE (XEXP (x, 0)) == CONST_INT
          || (XEXP (x, 1) == frame_pointer_rtx
              || (ARG_POINTER_REGNUM != FRAME_POINTER_REGNUM
                  && XEXP (x, 1) == arg_pointer_rtx)))
        {
          rtx t = XEXP (x, 0);
          XEXP (x, 0) = XEXP (x, 1);
          XEXP (x, 1) = t;
        }
      break;
#endif
    }

  /* Replace this rtx with a copy of itself.  */

  x = rtx_alloc (code);
  bcopy (orig, x, (sizeof (*x) - sizeof (x->fld)
                   + sizeof (x->fld[0]) * GET_RTX_LENGTH (code)));

  /* Now scan the subexpressions recursively.
     We can store any replaced subexpressions directly into X
     since we know X is not shared!  Any vectors in X
     must be copied if X was copied.  */

  format_ptr = GET_RTX_FORMAT (code);

  for (i = 0; i < GET_RTX_LENGTH (code); i++)
    {
      switch (*format_ptr++)
        {
        case 'e':
          XEXP (x, i) = copy_for_inline (XEXP (x, i));
          break;

        case 'u':
          /* Change any references to old-insns to point to the
             corresponding copied insns.  */
          XEXP (x, i) = insn_map[INSN_UID (XEXP (x, i))];
          break;

        case 'E':
          if (XVEC (x, i) != NULL && XVECLEN (x, i) != 0)
            {
              register int j;

              XVEC (x, i) = gen_rtvec_v (XVECLEN (x, i), &XVECEXP (x, i, 0));
              for (j = 0; j < XVECLEN (x, i); j++)
                XVECEXP (x, i, j)
                  = copy_for_inline (XVECEXP (x, i, j));
            }
          break;
        }
    }

  if (code == ASM_OPERANDS && orig_asm_operands_vector == 0)
    {
      orig_asm_operands_vector = XVEC (orig, 3);
      copy_asm_operands_vector = XVEC (x, 3);
      copy_asm_constraints_vector = XVEC (x, 4);
    }

  return x;
}

/* Unfortunately, we need a global copy of const_equiv map for communication
   with a function called from note_stores.  Be *very* careful that this
   is used properly in the presence of recursion.  */

rtx *global_const_equiv_map;
\f
#define FIXED_BASE_PLUS_P(X) \
  (GET_CODE (X) == PLUS && GET_CODE (XEXP (X, 1)) == CONST_INT  \
   && GET_CODE (XEXP (X, 0)) == REG                             \
   && REGNO (XEXP (X, 0)) >= FIRST_VIRTUAL_REGISTER             \
   && REGNO (XEXP (X, 0)) < LAST_VIRTUAL_REGISTER)

/* Integrate the procedure defined by FNDECL.  Note that this function
   may wind up calling itself.  Since the static variables are not
   reentrant, we do not assign them until after the possibility
   or recursion is eliminated.

   If IGNORE is nonzero, do not produce a value.
   Otherwise store the value in TARGET if it is nonzero and that is convenient.

   Value is:
   (rtx)-1 if we could not substitute the function
   0 if we substituted it and it does not produce a value
   else an rtx for where the value is stored.  */

rtx
expand_inline_function (fndecl, parms, target, ignore, type, structure_value_addr)
     tree fndecl, parms;
     rtx target;
     int ignore;
     tree type;
     rtx structure_value_addr;
{
  tree formal, actual;
  rtx header = DECL_SAVED_INSNS (fndecl);
  rtx insns = FIRST_FUNCTION_INSN (header);
  rtx parm_insns = FIRST_PARM_INSN (header);
  tree *arg_trees;
  rtx *arg_vals;
  rtx insn;
  int max_regno;
  int equiv_map_size;
  register int i;
  int min_labelno = FIRST_LABELNO (header);
  int max_labelno = LAST_LABELNO (header);
  int nargs;
  rtx local_return_label = 0;
  rtx loc;
  rtx temp;
  struct inline_remap *map;
  rtx cc0_insn = 0;
  rtvec arg_vector = ORIGINAL_ARG_VECTOR (header);

  /* Allow for equivalences of the pseudos we make for virtual fp and ap.  */
  max_regno = MAX_REGNUM (header) + 3;
  if (max_regno < FIRST_PSEUDO_REGISTER)
    abort ();

  nargs = list_length (DECL_ARGUMENTS (fndecl));

  /* We expect PARMS to have the right length; don't crash if not.  */
  if (list_length (parms) != nargs)
    return (rtx)-1;
  /* Also check that the parms type match.  Since the appropriate
     conversions or default promotions have already been applied,
     the machine modes should match exactly.  */
  for (formal = DECL_ARGUMENTS (fndecl),
       actual = parms;
       formal;
       formal = TREE_CHAIN (formal),
       actual = TREE_CHAIN (actual))
    {
      tree arg = TREE_VALUE (actual);
      enum machine_mode mode = TYPE_MODE (DECL_ARG_TYPE (formal));
      if (mode != TYPE_MODE (TREE_TYPE (arg)))
        return (rtx)-1;
      /* If they are block mode, the types should match exactly.
         They don't match exactly if TREE_TYPE (FORMAL) == ERROR_MARK_NODE,
         which could happen if the parameter has incomplete type.  */
      if (mode == BLKmode && TREE_TYPE (arg) != TREE_TYPE (formal))
        return (rtx)-1;
    }

  /* Make a binding contour to keep inline cleanups called at
     outer function-scope level from looking like they are shadowing
     parameter declarations.  */
  pushlevel (0);

  /* Make a fresh binding contour that we can easily remove.  */
  pushlevel (0);
  expand_start_bindings (0);
  if (GET_CODE (parm_insns) == NOTE
      && NOTE_LINE_NUMBER (parm_insns) > 0)
    emit_note (NOTE_SOURCE_FILE (parm_insns), NOTE_LINE_NUMBER (parm_insns));

  /* Expand the function arguments.  Do this first so that any
     new registers get created before we allocate the maps.  */

  arg_vals = (rtx *) alloca (nargs * sizeof (rtx));
  arg_trees = (tree *) alloca (nargs * sizeof (tree));

  for (formal = DECL_ARGUMENTS (fndecl), actual = parms, i = 0;
       formal;
       formal = TREE_CHAIN (formal), actual = TREE_CHAIN (actual), i++)
    {
      /* Actual parameter, converted to the type of the argument within the
         function.  */
      tree arg = convert (TREE_TYPE (formal), TREE_VALUE (actual));
      /* Mode of the variable used within the function.  */
      enum machine_mode mode = TYPE_MODE (TREE_TYPE (formal));
      /* Where parameter is located in the function.  */
      rtx copy;

      emit_note (DECL_SOURCE_FILE (formal), DECL_SOURCE_LINE (formal));

      arg_trees[i] = arg;
      loc = RTVEC_ELT (arg_vector, i);

      /* If this is an object passed by invisible reference, we copy the
         object into a stack slot and save its address.  If this will go
         into memory, we do nothing now.  Otherwise, we just expand the
         argument.  */
      if (GET_CODE (loc) == MEM && GET_CODE (XEXP (loc, 0)) == REG
          && REGNO (XEXP (loc, 0)) > LAST_VIRTUAL_REGISTER)
        {
          enum machine_mode mode = TYPE_MODE (TREE_TYPE (arg));
          rtx stack_slot = assign_stack_temp (mode, int_size_in_bytes (TREE_TYPE (arg)), 1);

          store_expr (arg, stack_slot, 0);

          arg_vals[i] = XEXP (stack_slot, 0);
        }
      else if (GET_CODE (loc) != MEM)
        arg_vals[i] = expand_expr (arg, 0, mode, EXPAND_SUM);
      else
        arg_vals[i] = 0;

      if (arg_vals[i] != 0
          && (! TREE_READONLY (formal)
              /* If the parameter is not read-only, copy our argument through
                 a register.  Also, we cannot use ARG_VALS[I] if it overlaps
                 TARGET in any way.  In the inline function, they will likely
                 be two different pseudos, and `safe_from_p' will make all
                 sorts of smart assumptions about their not conflicting.
                 But if ARG_VALS[I] overlaps TARGET, these assumptions are
                 wrong, so put ARG_VALS[I] into a fresh register.  */
              || (target != 0
                  && (GET_CODE (arg_vals[i]) == REG
                      || GET_CODE (arg_vals[i]) == SUBREG
                      || GET_CODE (arg_vals[i]) == MEM)
                  && reg_overlap_mentioned_p (arg_vals[i], target))))
        arg_vals[i] = copy_to_mode_reg (mode, arg_vals[i]);
    }
        
  /* Allocate the structures we use to remap things.  */

  map = (struct inline_remap *) alloca (sizeof (struct inline_remap));
  map->fndecl = fndecl;

  map->reg_map = (rtx *) alloca (max_regno * sizeof (rtx));
  bzero (map->reg_map, max_regno * sizeof (rtx));

  map->label_map = (rtx *)alloca ((max_labelno - min_labelno) * sizeof (rtx));
  map->label_map -= min_labelno;

  map->insn_map = (rtx *) alloca (INSN_UID (header) * sizeof (rtx));
  bzero (map->insn_map, INSN_UID (header) * sizeof (rtx));
  map->min_insnno = 0;
  map->max_insnno = INSN_UID (header);

  /* const_equiv_map maps pseudos in our routine to constants, so it needs to
     be large enough for all our pseudos.  This is the number we are currently
     using plus the number in the called routine, plus one for each arg and
     one for the return value.  */
  equiv_map_size
    = max_reg_num () + (max_regno - FIRST_PSEUDO_REGISTER) + nargs + 1;

  map->const_equiv_map = (rtx *)alloca (equiv_map_size * sizeof (rtx));
  bzero (map->const_equiv_map, equiv_map_size * sizeof (rtx));

  map->const_age_map = (unsigned *)alloca (equiv_map_size * sizeof (unsigned));
  bzero (map->const_age_map, equiv_map_size * sizeof (unsigned));
  map->const_age = 0;

  /* Record the current insn in case we have to set up pointers to frame
     and argument memory blocks.  */
  map->insns_at_start = get_last_insn ();

  /* Update the outgoing argument size to allow for those in the inlined
     function.  */
  if (OUTGOING_ARGS_SIZE (header) > current_function_outgoing_args_size)
    current_function_outgoing_args_size = OUTGOING_ARGS_SIZE (header);

  /* If the inline function needs to make PIC references, that means
     that this function's PIC offset table must be used.  */
  if (FUNCTION_FLAGS (header) & FUNCTION_FLAGS_USES_PIC_OFFSET_TABLE)
    current_function_uses_pic_offset_table = 1;

  /* Process each argument.  For each, set up things so that the function's
     reference to the argument will refer to the argument being passed.
     We only replace REG with REG here.  Any simplifications are done
     via const_equiv_map.

     We make two passes:  In the first, we deal with parameters that will
     be placed into registers, since we need to ensure that the allocated
     register number fits in const_equiv_map.  Then we store all non-register
     parameters into their memory location.  */

  for (i = 0; i < nargs; i++)
    {
      rtx copy = arg_vals[i];

      loc = RTVEC_ELT (arg_vector, i);

      /* There are three cases, each handled separately.  */
      if (GET_CODE (loc) == MEM && GET_CODE (XEXP (loc, 0)) == REG
          && REGNO (XEXP (loc, 0)) > LAST_VIRTUAL_REGISTER)
        {
          /* This must be an object passed by invisible reference (it could
             also be a variable-sized object, but we forbid inlining functions
             with variable-sized arguments).  COPY is the address of the
             actual value (this computation will cause it to be copied).  We
             map that address for the register, noting the actual address as
             an equivalent in case it can be substituted into the insns.  */

          if (GET_CODE (copy) != REG)
            {
              temp = copy_addr_to_reg (copy);
              if (CONSTANT_P (copy) || FIXED_BASE_PLUS_P (copy))
                {
                  map->const_equiv_map[REGNO (temp)] = copy;
                  map->const_age_map[REGNO (temp)] = CONST_AGE_PARM;
                }
              copy = temp;
            }
          map->reg_map[REGNO (XEXP (loc, 0))] = copy;
        }
      else if (GET_CODE (loc) == MEM)
        {
          /* This is the case of a parameter that lives in memory.
             It will live in the block we allocate in the called routine's
             frame that simulates the incoming argument area.  Do nothing
             now; we will call store_expr later.  */
          ;
        }
      else if (GET_CODE (loc) == REG)
        {
          /* This is the good case where the parameter is in a register.
             If it is read-only and our argument is a constant, set up the
             constant equivalence.  */
          if (GET_CODE (copy) != REG && GET_CODE (copy) != SUBREG)
            {
              temp = copy_to_mode_reg (GET_MODE (loc), copy);
              if (CONSTANT_P (copy) || FIXED_BASE_PLUS_P (copy))
                {
                  map->const_equiv_map[REGNO (temp)] = copy;
                  map->const_age_map[REGNO (temp)] = CONST_AGE_PARM;
                }
              copy = temp;
            }
          map->reg_map[REGNO (loc)] = copy;
        }
      else
        abort ();

      /* Free any temporaries we made setting up this parameter.  */
      free_temp_slots ();
    }

  /* Now do the parameters that will be placed in memory.  */

  for (formal = DECL_ARGUMENTS (fndecl), i = 0;
       formal; formal = TREE_CHAIN (formal), i++)
    {
      rtx copy = arg_vals[i];

      loc = RTVEC_ELT (arg_vector, i);

      if (GET_CODE (loc) == MEM
          /* Exclude case handled above.  */
          && ! (GET_CODE (XEXP (loc, 0)) == REG
                && REGNO (XEXP (loc, 0)) > LAST_VIRTUAL_REGISTER))
        {
          emit_note (DECL_SOURCE_FILE (formal), DECL_SOURCE_LINE (formal));

          /* Compute the address in the area we reserved and store the
             value there.  */
          temp = copy_rtx_and_substitute (loc, map);
          subst_constants (&temp, 0, map);
          apply_change_group ();
          if (! memory_address_p (GET_MODE (temp), XEXP (temp, 0)))
            temp = change_address (temp, VOIDmode, XEXP (temp, 0));
          store_expr (arg_trees[i], temp, 0);

          /* Free any temporaries we made setting up this parameter.  */
          free_temp_slots ();
        }
    }

  /* Deal with the places that the function puts its result.
     We are driven by what is placed into DECL_RESULT.

     Initially, we assume that we don't have anything special handling for
     REG_FUNCTION_RETURN_VALUE_P.  */

  map->inline_target = 0;
  loc = DECL_RTL (DECL_RESULT (fndecl));
  if (TYPE_MODE (type) == VOIDmode)
    /* There is no return value to worry about.  */
    ;
  else if (GET_CODE (loc) == MEM)
    {
      if (! structure_value_addr || ! aggregate_value_p (DECL_RESULT (fndecl)))
        abort ();
  
      /* Pass the function the address in which to return a structure value.
         Note that a constructor can cause someone to call us with
         STRUCTURE_VALUE_ADDR, but the initialization takes place
         via the first parameter, rather than the struct return address.

         We have two cases:  If the address is a simple register indirect,
         use the mapping mechanism to point that register to our structure
         return address.  Otherwise, store the structure return value into
         the place that it will be referenced from.  */

      if (GET_CODE (XEXP (loc, 0)) == REG)
        {
          temp = force_reg (Pmode, structure_value_addr);
          map->reg_map[REGNO (XEXP (loc, 0))] = temp;
          if (CONSTANT_P (structure_value_addr)
              || (GET_CODE (structure_value_addr) == PLUS
                  && XEXP (structure_value_addr, 0) == virtual_stack_vars_rtx
                  && GET_CODE (XEXP (structure_value_addr, 1)) == CONST_INT))
            {
              map->const_equiv_map[REGNO (temp)] = structure_value_addr;
              map->const_age_map[REGNO (temp)] = CONST_AGE_PARM;
            }
        }
      else
        {
          temp = copy_rtx_and_substitute (loc, map);
          subst_constants (&temp, 0, map);
          apply_change_group ();
          emit_move_insn (temp, structure_value_addr);
        }
    }
  else if (ignore)
    /* We will ignore the result value, so don't look at its structure.
       Note that preparations for an aggregate return value
       do need to be made (above) even if it will be ignored.  */
    ;
  else if (GET_CODE (loc) == REG)
    {
      /* The function returns an object in a register and we use the return
         value.  Set up our target for remapping.  */

      /* Machine mode function was declared to return.   */
      enum machine_mode departing_mode = TYPE_MODE (type);
      /* (Possibly wider) machine mode it actually computes
         (for the sake of callers that fail to declare it right).  */
      enum machine_mode arriving_mode
        = TYPE_MODE (TREE_TYPE (DECL_RESULT (fndecl)));
      rtx reg_to_map;

      /* Don't use MEMs as direct targets because on some machines
         substituting a MEM for a REG makes invalid insns.
         Let the combiner substitute the MEM if that is valid.  */
      if (target == 0 || GET_CODE (target) != REG
          || GET_MODE (target) != departing_mode)
        target = gen_reg_rtx (departing_mode);

      /* If function's value was promoted before return,
         avoid machine mode mismatch when we substitute INLINE_TARGET.
         But TARGET is what we will return to the caller.  */
      if (arriving_mode != departing_mode)
        reg_to_map = gen_rtx (SUBREG, arriving_mode, target, 0);
      else
        reg_to_map = target;

      /* Usually, the result value is the machine's return register.
         Sometimes it may be a pseudo. Handle both cases.  */
      if (REG_FUNCTION_VALUE_P (loc))
        map->inline_target = reg_to_map;
      else
        map->reg_map[REGNO (loc)] = reg_to_map;
    }

  /* Make new label equivalences for the labels in the called function.  */
  for (i = min_labelno; i < max_labelno; i++)
    map->label_map[i] = gen_label_rtx ();

  /* Perform postincrements before actually calling the function.  */
  emit_queue ();

  /* Clean up stack so that variables might have smaller offsets.  */
  do_pending_stack_adjust ();

  /* Save a copy of the location of const_equiv_map for mark_stores, called
     via note_stores.  */
  global_const_equiv_map = map->const_equiv_map;

  /* Now copy the insns one by one.  Do this in two passes, first the insns and
     then their REG_NOTES, just like save_for_inline.  */

  /* This loop is very similar to the loop in copy_loop_body in unroll.c.  */

  for (insn = insns; insn; insn = NEXT_INSN (insn))
    {
      rtx copy, pattern;

      map->orig_asm_operands_vector = 0;

      switch (GET_CODE (insn))
        {
        case INSN:
          pattern = PATTERN (insn);
          copy = 0;
          if (GET_CODE (pattern) == USE
              && GET_CODE (XEXP (pattern, 0)) == REG
              && REG_FUNCTION_VALUE_P (XEXP (pattern, 0)))
            /* The (USE (REG n)) at return from the function should
               be ignored since we are changing (REG n) into
               inline_target.  */
            break;

          /* Ignore setting a function value that we don't want to use.  */
          if (map->inline_target == 0
              && GET_CODE (pattern) == SET
              && GET_CODE (SET_DEST (pattern)) == REG
              && REG_FUNCTION_VALUE_P (SET_DEST (pattern)))
            break;

          copy = emit_insn (copy_rtx_and_substitute (pattern, map));
          /* REG_NOTES will be copied later.  */

#ifdef HAVE_cc0
          /* If this insn is setting CC0, it may need to look at
             the insn that uses CC0 to see what type of insn it is.
             In that case, the call to recog via validate_change will
             fail.  So don't substitute constants here.  Instead,
             do it when we emit the following insn.

             For example, see the pyr.md file.  That machine has signed and
             unsigned compares.  The compare patterns must check the
             following branch insn to see which what kind of compare to
             emit.

             If the previous insn set CC0, substitute constants on it as
             well.  */
          if (sets_cc0_p (PATTERN (copy)) != 0)
            cc0_insn = copy;
          else
            {
              if (cc0_insn)
                try_constants (cc0_insn, map);
              cc0_insn = 0;
              try_constants (copy, map);
            }
#else
          try_constants (copy, map);
#endif
          break;

        case JUMP_INSN:
          if (GET_CODE (PATTERN (insn)) == RETURN)
            {
              if (local_return_label == 0)
                local_return_label = gen_label_rtx ();
              pattern = gen_jump (local_return_label);
            }
          else
            pattern = copy_rtx_and_substitute (PATTERN (insn), map);

          copy = emit_jump_insn (pattern);

#ifdef HAVE_cc0
          if (cc0_insn)
            try_constants (cc0_insn, map);
          cc0_insn = 0;
#endif
          try_constants (copy, map);

          /* If this used to be a conditional jump insn but whose branch
             direction is now know, we must do something special.  */
          if (condjump_p (insn) && ! simplejump_p (insn) && map->last_pc_value)
            {
#ifdef HAVE_cc0
              /* The previous insn set cc0 for us.  So delete it.  */
              delete_insn (PREV_INSN (copy));
#endif

              /* If this is now a no-op, delete it.  */
              if (map->last_pc_value == pc_rtx)
                {
                  delete_insn (copy);
                  copy = 0;
                }
              else
                /* Otherwise, this is unconditional jump so we must put a
                   BARRIER after it.  We could do some dead code elimination
                   here, but jump.c will do it just as well.  */
                emit_barrier ();
            }
          break;

        case CALL_INSN:
          pattern = copy_rtx_and_substitute (PATTERN (insn), map);
          copy = emit_call_insn (pattern);

#ifdef HAVE_cc0
          if (cc0_insn)
            try_constants (cc0_insn, map);
          cc0_insn = 0;
#endif
          try_constants (copy, map);

          /* Be lazy and assume CALL_INSNs clobber all hard registers.  */
          for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
            map->const_equiv_map[i] = 0;
          break;

        case CODE_LABEL:
          copy = emit_label (map->label_map[CODE_LABEL_NUMBER (insn)]);
          map->const_age++;
          break;

        case BARRIER:
          copy = emit_barrier ();
          break;

        case NOTE:
          /* It is important to discard function-end and function-beg notes,
             so we have only one of each in the current function.
             Also, NOTE_INSN_DELETED notes aren't useful (save_for_inline
             deleted these in the copy used for continuing compilation,
             not the copy used for inlining).  */
          if (NOTE_LINE_NUMBER (insn) != NOTE_INSN_FUNCTION_END
              && NOTE_LINE_NUMBER (insn) != NOTE_INSN_FUNCTION_BEG
              && NOTE_LINE_NUMBER (insn) != NOTE_INSN_DELETED)
            copy = emit_note (NOTE_SOURCE_FILE (insn), NOTE_LINE_NUMBER (insn));
          else
            copy = 0;
          break;

        default:
          abort ();
          break;
        }

      if (copy)
        RTX_INTEGRATED_P (copy) = 1;

      map->insn_map[INSN_UID (insn)] = copy;
    }

  /* Now copy the REG_NOTES.  */
  for (insn = insns; insn; insn = NEXT_INSN (insn))
    if (GET_RTX_CLASS (GET_CODE (insn)) == 'i'
        && map->insn_map[INSN_UID (insn)])
      REG_NOTES (map->insn_map[INSN_UID (insn)])
        = copy_rtx_and_substitute (REG_NOTES (insn), map);

  if (local_return_label)
    emit_label (local_return_label);

  /* Make copies of the decls of the symbols in the inline function, so that
     the copies of the variables get declared in the current function.  Set
     up things so that lookup_static_chain knows that to interpret registers
     in SAVE_EXPRs for TYPE_SIZEs as local.  */

  inline_function_decl = fndecl;
  integrate_decl_tree ((tree) ORIGINAL_DECL_INITIAL (header), 0, map, 0);
  integrate_parm_decls (DECL_ARGUMENTS (fndecl), map, arg_vector);
  inline_function_decl = 0;

  /* End the scope containing the copied formal parameter variables.  */

  expand_end_bindings (getdecls (), 1, 1);
  poplevel (1, 1, 0);
  poplevel (0, 0, 0);
  emit_line_note (input_filename, lineno);

  if (structure_value_addr)
    return gen_rtx (MEM, TYPE_MODE (type),
                    memory_address (TYPE_MODE (type), structure_value_addr));
  return target;
}
\f
/* Given a chain of PARM_DECLs, ARGS, copy each decl into a VAR_DECL,
   push all of those decls and give each one the corresponding home.  */

static void
integrate_parm_decls (args, map, arg_vector)
     tree args;
     struct inline_remap *map;
     rtvec arg_vector;
{
  register tree tail;
  register int i;

  for (tail = args, i = 0; tail; tail = TREE_CHAIN (tail), i++)
    {
      register tree decl = build_decl (VAR_DECL, DECL_NAME (tail),
                                       TREE_TYPE (tail));
      rtx new_decl_rtl
        = copy_rtx_and_substitute (RTVEC_ELT (arg_vector, i), map);

      /* These args would always appear unused, if not for this.  */
      TREE_USED (decl) = 1;
      /* Prevent warning for shadowing with these.  */
      DECL_FROM_INLINE (decl) = 1;
      pushdecl (decl);
      /* Fully instantiate the address with the equivalent form so that the
         debugging information contains the actual register, instead of the
         virtual register.   Do this by not passing an insn to
         subst_constants.  */
      subst_constants (&new_decl_rtl, 0, map);
      apply_change_group ();
      DECL_RTL (decl) = new_decl_rtl;
    }
}

/* Given a BLOCK node LET, push decls and levels so as to construct in the
   current function a tree of contexts isomorphic to the one that is given.

   LEVEL indicates how far down into the BLOCK tree is the node we are
   currently traversing.  It is always zero for the initial call.

   MAP, if nonzero, is a pointer to a inline_remap map which indicates how
   registers used in the DECL_RTL field should be remapped.  If it is zero,
   no mapping is necessary.

   FUNCTIONBODY indicates whether the top level block tree corresponds to
   a function body.  This is identical in meaning to the functionbody
   argument of poplevel.  */

static void
integrate_decl_tree (let, level, map, functionbody)
     tree let;
     int level;
     struct inline_remap *map;
     int functionbody;
{
  tree t, node;

  pushlevel (0);
  
  for (t = BLOCK_VARS (let); t; t = TREE_CHAIN (t))
    {
      tree d = build_decl (TREE_CODE (t), DECL_NAME (t), TREE_TYPE (t));
      DECL_SOURCE_LINE (d) = DECL_SOURCE_LINE (t);
      DECL_SOURCE_FILE (d) = DECL_SOURCE_FILE (t);
      if (! functionbody && DECL_RTL (t) != 0)
        {
          DECL_RTL (d) = copy_rtx_and_substitute (DECL_RTL (t), map);
          /* Fully instantiate the address with the equivalent form so that the
             debugging information contains the actual register, instead of the
             virtual register.   Do this by not passing an insn to
             subst_constants.  */
          subst_constants (&DECL_RTL (d), 0, map);
          apply_change_group ();
        }
      else if (DECL_RTL (t))
        DECL_RTL (d) = copy_rtx (DECL_RTL (t));
      TREE_EXTERNAL (d) = TREE_EXTERNAL (t);
      TREE_STATIC (d) = TREE_STATIC (t);
      TREE_PUBLIC (d) = TREE_PUBLIC (t);
      TREE_CONSTANT (d) = TREE_CONSTANT (t);
      TREE_ADDRESSABLE (d) = TREE_ADDRESSABLE (t);
      TREE_READONLY (d) = TREE_READONLY (t);
      TREE_SIDE_EFFECTS (d) = TREE_SIDE_EFFECTS (t);
      /* These args would always appear unused, if not for this.  */
      TREE_USED (d) = 1;
      /* Prevent warning for shadowing with these.  */
      DECL_FROM_INLINE (d) = 1;
      pushdecl (d);
    }

  for (t = BLOCK_SUBBLOCKS (let); t; t = TREE_CHAIN (t))
    integrate_decl_tree (t, level + 1, map, functionbody);

  node = poplevel (level > 0, 0, level == 0 && functionbody);
  if (node)
    TREE_USED (node) = TREE_USED (let);
}
\f
/* Create a new copy of an rtx.
   Recursively copies the operands of the rtx,
   except for those few rtx codes that are sharable.

   We always return an rtx that is similar to that incoming rtx, with the
   exception of possibly changing a REG to a SUBREG or vice versa.  No
   rtl is ever emitted.

   Handle constants that need to be placed in the constant pool by
   calling `force_const_mem'.  */

rtx
copy_rtx_and_substitute (orig, map)
     register rtx orig;
     struct inline_remap *map;
{
  register rtx copy, temp;
  register int i, j;
  register RTX_CODE code;
  register enum machine_mode mode;
  register char *format_ptr;
  int regno;

  if (orig == 0)
    return 0;

  code = GET_CODE (orig);
  mode = GET_MODE (orig);

  switch (code)
    {
    case REG:
      /* If the stack pointer register shows up, it must be part of
         stack-adjustments (*not* because we eliminated the frame pointer!).
         Small hard registers are returned as-is.  Pseudo-registers
         go through their `reg_map'.  */
      regno = REGNO (orig);
      if (regno <= LAST_VIRTUAL_REGISTER)
        {
          /* Some hard registers are also mapped,
             but others are not translated.  */
          if (map->reg_map[regno] != 0)
            return map->reg_map[regno];

          /* If this is the virtual frame pointer, make space in current
             function's stack frame for the stack frame of the inline function.

             Copy the address of this area into a pseudo.  Map
             virtual_stack_vars_rtx to this pseudo and set up a constant
             equivalence for it to be the address.  This will substitute the
             address into insns where it can be substituted and use the new
             pseudo where it can't.  */
          if (regno == VIRTUAL_STACK_VARS_REGNUM)
            {
              rtx loc, seq;
              int size = DECL_FRAME_SIZE (map->fndecl);
              int rounded;

              start_sequence ();
              loc = assign_stack_temp (BLKmode, size, 1);
              loc = XEXP (loc, 0);
#ifdef FRAME_GROWS_DOWNWARD
              /* In this case, virtual_stack_vars_rtx points to one byte
                 higher than the top of the frame area.  So compute the offset
                 to one byte higher than our substitute frame.
                 Keep the fake frame pointer aligned like a real one.  */
              rounded = CEIL_ROUND (size, BIGGEST_ALIGNMENT / BITS_PER_UNIT);
              loc = plus_constant (loc, rounded);
#endif
              map->reg_map[regno] = force_operand (loc, 0);
              map->const_equiv_map[regno] = loc;
              map->const_age_map[regno] = CONST_AGE_PARM;

              seq = gen_sequence ();
              end_sequence ();
              emit_insn_after (seq, map->insns_at_start);
              return map->reg_map[regno];
            }
          else if (regno == VIRTUAL_INCOMING_ARGS_REGNUM)
            {
              /* Do the same for a block to contain any arguments referenced
                 in memory. */
              rtx loc, seq;
              int size = FUNCTION_ARGS_SIZE (DECL_SAVED_INSNS (map->fndecl));

              start_sequence ();
              loc = assign_stack_temp (BLKmode, size, 1);
              loc = XEXP (loc, 0);
              map->reg_map[regno] = force_operand (loc, 0);
              map->const_equiv_map[regno] = loc;
              map->const_age_map[regno] = CONST_AGE_PARM;

              seq = gen_sequence ();
              end_sequence ();
              emit_insn_after (seq, map->insns_at_start);
              return map->reg_map[regno];
            }
          else if (REG_FUNCTION_VALUE_P (orig))
            {
              /* This is a reference to the function return value.  If
                 the function doesn't have a return value, error.  If the
                 mode doesn't agree, make a SUBREG.  */
              if (map->inline_target == 0)
                /* Must be unrolling loops or replicating code if we
                   reach here, so return the register unchanged.  */
                return orig;
              else if (mode != GET_MODE (map->inline_target))
                return gen_rtx (SUBREG, mode, map->inline_target, 0);
              else
                return map->inline_target;
            }
          return orig;
        }
      if (map->reg_map[regno] == NULL)
        {
          map->reg_map[regno] = gen_reg_rtx (mode);
          REG_USERVAR_P (map->reg_map[regno]) = REG_USERVAR_P (orig);
          REG_LOOP_TEST_P (map->reg_map[regno]) = REG_LOOP_TEST_P (orig);
          RTX_UNCHANGING_P (map->reg_map[regno]) = RTX_UNCHANGING_P (orig);
          /* A reg with REG_FUNCTION_VALUE_P true will never reach here.  */
        }
      return map->reg_map[regno];

    case SUBREG:
      copy = copy_rtx_and_substitute (SUBREG_REG (orig), map);
      /* SUBREG is ordinary, but don't make nested SUBREGs.  */
      if (GET_CODE (copy) == SUBREG)
        return gen_rtx (SUBREG, GET_MODE (orig), SUBREG_REG (copy),
                        SUBREG_WORD (orig) + SUBREG_WORD (copy));
      else
        return gen_rtx (SUBREG, GET_MODE (orig), copy,
                        SUBREG_WORD (orig));

    case USE:
    case CLOBBER:
      /* USE and CLOBBER are ordinary, but we convert (use (subreg foo))
         to (use foo).  */
      copy = copy_rtx_and_substitute (XEXP (orig, 0), map);
      if (GET_CODE (copy) == SUBREG)
        copy = SUBREG_REG (copy);
      return gen_rtx (code, VOIDmode, copy);

    case CODE_LABEL:
      LABEL_PRESERVE_P (map->label_map[CODE_LABEL_NUMBER (orig)])
        = LABEL_PRESERVE_P (orig);
      return map->label_map[CODE_LABEL_NUMBER (orig)];

    case LABEL_REF:
      copy = rtx_alloc (LABEL_REF);
      PUT_MODE (copy, mode);
      XEXP (copy, 0) = map->label_map[CODE_LABEL_NUMBER (XEXP (orig, 0))];
      LABEL_OUTSIDE_LOOP_P (copy) = LABEL_OUTSIDE_LOOP_P (orig);
      return copy;

    case PC:
    case CC0:
    case CONST_INT:
    case SYMBOL_REF:
      return orig;

    case CONST_DOUBLE:
      /* We have to make a new copy of this CONST_DOUBLE because don't want
         to use the old value of CONST_DOUBLE_MEM.  Also, this may be a
         duplicate of a CONST_DOUBLE we have already seen.  */
      if (GET_MODE_CLASS (GET_MODE (orig)) == MODE_FLOAT)
        {
          REAL_VALUE_TYPE d;

          REAL_VALUE_FROM_CONST_DOUBLE (d, orig);
          return immed_real_const_1 (d, GET_MODE (orig));
        }
      else
        return immed_double_const (CONST_DOUBLE_LOW (orig),
                                   CONST_DOUBLE_HIGH (orig), VOIDmode);

    case CONST:
      /* Make new constant pool entry for a constant
         that was in the pool of the inline function.  */
      if (RTX_INTEGRATED_P (orig))
        {
          /* If this was an address of a constant pool entry that itself
             had to be placed in the constant pool, it might not be a
             valid address.  So the recursive call below might turn it
             into a register.  In that case, it isn't a constant any
             more, so return it.  This has the potential of changing a
             MEM into a REG, but we'll assume that it safe.  */
          temp = copy_rtx_and_substitute (XEXP (orig, 0), map);
          if (! CONSTANT_P (temp))
            return temp;
          return validize_mem (force_const_mem (GET_MODE (orig), temp));
        }
      break;

    case ADDRESS:
      /* If from constant pool address, make new constant pool entry and
         return its address.  */
      if (! RTX_INTEGRATED_P (orig))
        abort ();

      temp = force_const_mem (GET_MODE (orig),
                              copy_rtx_and_substitute (XEXP (orig, 0), map));

#if 0
      /* Legitimizing the address here is incorrect.

         The only ADDRESS rtx's that can reach here are ones created by
         save_constants.  Hence the operand of the ADDRESS is always legal
         in this position of the instruction, since the original rtx without
         the ADDRESS was legal.

         The reason we don't legitimize the address here is that on the
         Sparc, the caller may have a (high ...) surrounding this ADDRESS.
         This code forces the operand of the address to a register, which
         fails because we can not take the HIGH part of a register.

         Also, change_address may create new registers.  These registers
         will not have valid reg_map entries.  This can cause try_constants()
         to fail because assumes that all registers in the rtx have valid
         reg_map entries, and it may end up replacing one of these new
         registers with junk. */

      if (! memory_address_p (GET_MODE (temp), XEXP (temp, 0)))
        temp = change_address (temp, GET_MODE (temp), XEXP (temp, 0));
#endif

      return XEXP (temp, 0);

    case ASM_OPERANDS:
      /* If a single asm insn contains multiple output operands
         then it contains multiple ASM_OPERANDS rtx's that share operand 3.
         We must make sure that the copied insn continues to share it.  */
      if (map->orig_asm_operands_vector == XVEC (orig, 3))
        {
          copy = rtx_alloc (ASM_OPERANDS);
          XSTR (copy, 0) = XSTR (orig, 0);
          XSTR (copy, 1) = XSTR (orig, 1);
          XINT (copy, 2) = XINT (orig, 2);
          XVEC (copy, 3) = map->copy_asm_operands_vector;
          XVEC (copy, 4) = map->copy_asm_constraints_vector;
          XSTR (copy, 5) = XSTR (orig, 5);
          XINT (copy, 6) = XINT (orig, 6);
          return copy;
        }
      break;

    case CALL:
      /* This is given special treatment because the first
         operand of a CALL is a (MEM ...) which may get
         forced into a register for cse.  This is undesirable
         if function-address cse isn't wanted or if we won't do cse.  */
#ifndef NO_FUNCTION_CSE
      if (! (optimize && ! flag_no_function_cse))
#endif
        return gen_rtx (CALL, GET_MODE (orig),
                        gen_rtx (MEM, GET_MODE (XEXP (orig, 0)),
                                 copy_rtx_and_substitute (XEXP (XEXP (orig, 0), 0), map)),
                        copy_rtx_and_substitute (XEXP (orig, 1), map));
      break;

#if 0
      /* Must be ifdefed out for loop unrolling to work.  */
    case RETURN:
      abort ();
#endif

    case SET:
      /* If this is setting fp or ap, it means that we have a nonlocal goto.
         Don't alter that.
         If the nonlocal goto is into the current function,
         this will result in unnecessarily bad code, but should work.  */
      if (SET_DEST (orig) == virtual_stack_vars_rtx
          || SET_DEST (orig) == virtual_incoming_args_rtx)
        return gen_rtx (SET, VOIDmode, SET_DEST (orig),
                        copy_rtx_and_substitute (SET_SRC (orig), map));
      break;

    case MEM:
      copy = rtx_alloc (MEM);
      PUT_MODE (copy, mode);
      XEXP (copy, 0) = copy_rtx_and_substitute (XEXP (orig, 0), map);
      MEM_IN_STRUCT_P (copy) = MEM_IN_STRUCT_P (orig);
      MEM_VOLATILE_P (copy) = MEM_VOLATILE_P (orig);
      RTX_UNCHANGING_P (copy) = RTX_UNCHANGING_P (orig);
      return copy;
    }

  copy = rtx_alloc (code);
  PUT_MODE (copy, mode);
  copy->in_struct = orig->in_struct;
  copy->volatil = orig->volatil;
  copy->unchanging = orig->unchanging;

  format_ptr = GET_RTX_FORMAT (GET_CODE (copy));

  for (i = 0; i < GET_RTX_LENGTH (GET_CODE (copy)); i++)
    {
      switch (*format_ptr++)
        {
        case '0':
          break;

        case 'e':
          XEXP (copy, i) = copy_rtx_and_substitute (XEXP (orig, i), map);
          break;

        case 'u':
          /* Change any references to old-insns to point to the
             corresponding copied insns.  */
          XEXP (copy, i) = map->insn_map[INSN_UID (XEXP (orig, i))];
          break;

        case 'E':
          XVEC (copy, i) = XVEC (orig, i);
          if (XVEC (orig, i) != NULL && XVECLEN (orig, i) != 0)
            {
              XVEC (copy, i) = rtvec_alloc (XVECLEN (orig, i));
              for (j = 0; j < XVECLEN (copy, i); j++)
                XVECEXP (copy, i, j)
                  = copy_rtx_and_substitute (XVECEXP (orig, i, j), map);
            }
          break;

        case 'i':
          XINT (copy, i) = XINT (orig, i);
          break;

        case 's':
          XSTR (copy, i) = XSTR (orig, i);
          break;

        default:
          abort ();
        }
    }

  if (code == ASM_OPERANDS && map->orig_asm_operands_vector == 0)
    {
      map->orig_asm_operands_vector = XVEC (orig, 3);
      map->copy_asm_operands_vector = XVEC (copy, 3);
      map->copy_asm_constraints_vector = XVEC (copy, 4);
    }

  return copy;
}
\f
/* Substitute known constant values into INSN, if that is valid.  */

void
try_constants (insn, map)
     rtx insn;
     struct inline_remap *map;
{
  int i;

  map->num_sets = 0;
  subst_constants (&PATTERN (insn), insn, map);

  /* Apply the changes if they are valid; otherwise discard them.  */
  apply_change_group ();

  /* Show we don't know the value of anything stored or clobbered.  */
  note_stores (PATTERN (insn), mark_stores);
  map->last_pc_value = 0;
#ifdef HAVE_cc0
  map->last_cc0_value = 0;
#endif

  /* Set up any constant equivalences made in this insn.  */
  for (i = 0; i < map->num_sets; i++)
    {
      if (GET_CODE (map->equiv_sets[i].dest) == REG)
        {
          int regno = REGNO (map->equiv_sets[i].dest);

          if (map->const_equiv_map[regno] == 0
              /* Following clause is a hack to make case work where GNU C++
                 reassigns a variable to make cse work right.  */
              || ! rtx_equal_p (map->const_equiv_map[regno],
                                map->equiv_sets[i].equiv))
            {
              map->const_equiv_map[regno] = map->equiv_sets[i].equiv;
              map->const_age_map[regno] = map->const_age;
            }
        }
      else if (map->equiv_sets[i].dest == pc_rtx)
        map->last_pc_value = map->equiv_sets[i].equiv;
#ifdef HAVE_cc0
      else if (map->equiv_sets[i].dest == cc0_rtx)
        map->last_cc0_value = map->equiv_sets[i].equiv;
#endif
    }
}
\f
/* Substitute known constants for pseudo regs in the contents of LOC,
   which are part of INSN.
   If INSN is zero, the substition should always be done (this is used to
   update DECL_RTL).
   These changes are taken out by try_constants if the result is not valid.

   Note that we are more concerned with determining when the result of a SET
   is a constant, for further propagation, than actually inserting constants
   into insns; cse will do the latter task better.

   This function is also used to adjust address of items previously addressed
   via the virtual stack variable or virtual incoming arguments registers.  */

static void
subst_constants (loc, insn, map)
     rtx *loc;
     rtx insn;
     struct inline_remap *map;
{
  rtx x = *loc;
  register int i;
  register enum rtx_code code;
  register char *format_ptr;
  int num_changes = num_validated_changes ();
  rtx new = 0;
  enum machine_mode op0_mode;

  code = GET_CODE (x);

  switch (code)
    {
    case PC:
    case CONST_INT:
    case CONST_DOUBLE:
    case SYMBOL_REF:
    case CONST:
    case LABEL_REF:
    case ADDRESS:
      return;

#ifdef HAVE_cc0
    case CC0:
      validate_change (insn, loc, map->last_cc0_value, 1);
      return;
#endif

    case USE:
    case CLOBBER:
      /* The only thing we can do with a USE or CLOBBER is possibly do
         some substitutions in a MEM within it.  */
      if (GET_CODE (XEXP (x, 0)) == MEM)
        subst_constants (&XEXP (XEXP (x, 0), 0), insn, map);
      return;

    case REG:
      /* Substitute for parms and known constants.  Don't replace
         hard regs used as user variables with constants.  */
      {
        int regno = REGNO (x);
        if (! (regno < FIRST_PSEUDO_REGISTER && REG_USERVAR_P (x))
            && map->const_equiv_map[regno] != 0
            && map->const_age_map[regno] >= map->const_age)
          validate_change (insn, loc, map->const_equiv_map[regno], 1);
        return;
      }

    case SUBREG:
      /* SUBREG is ordinary, but don't make nested SUBREGs and try to simplify
         constants.  */
      {
        rtx inner = SUBREG_REG (x);
        rtx new = 0;

        /* We can't call subst_constants on &SUBREG_REG (x) because any
           constant or SUBREG wouldn't be valid inside our SUBEG.  Instead,
           see what is inside, try to form the new SUBREG and see if that is
           valid.  We handle two cases: extracting a full word in an 
           integral mode and extracting the low part.  */
        subst_constants (&inner, 0, map);

        if (GET_MODE_CLASS (GET_MODE (x)) == MODE_INT
            && GET_MODE_SIZE (GET_MODE (x)) == UNITS_PER_WORD
            && GET_MODE (SUBREG_REG (x)) != VOIDmode)
          new = operand_subword (inner, SUBREG_WORD (x), 0,
                                 GET_MODE (SUBREG_REG (x)));

        if (new == 0 && subreg_lowpart_p (x))
          new = gen_lowpart_common (GET_MODE (x), inner);

        if (new)
          validate_change (insn, loc, new, 1);

        return;
      }

    case MEM:
      subst_constants (&XEXP (x, 0), insn, map);

      /* If a memory address got spoiled, change it back.  */
      if (insn != 0 && num_validated_changes () != num_changes
          && !memory_address_p (GET_MODE (x), XEXP (x, 0)))
        cancel_changes (num_changes);
      return;

    case SET:
      {
        /* Substitute constants in our source, and in any arguments to a
           complex (e..g, ZERO_EXTRACT) destination, but not in the destination
           itself.  */
        rtx *dest_loc = &SET_DEST (x);
        rtx dest = *dest_loc;
        rtx src, tem;

        subst_constants (&SET_SRC (x), insn, map);
        src = SET_SRC (x);

        while (GET_CODE (*dest_loc) == ZERO_EXTRACT
               || GET_CODE (*dest_loc) == SIGN_EXTRACT
               || GET_CODE (*dest_loc) == SUBREG
               || GET_CODE (*dest_loc) == STRICT_LOW_PART)
          {
            if (GET_CODE (*dest_loc) == ZERO_EXTRACT)
              {
                subst_constants (&XEXP (*dest_loc, 1), insn, map);
                subst_constants (&XEXP (*dest_loc, 2), insn, map);
              }
            dest_loc = &XEXP (*dest_loc, 0);
          }

        /* Check for the case of DEST a SUBREG, both it and the underlying
           register are less than one word, and the SUBREG has the wider mode.
           In the case, we are really setting the underlying register to the
           source converted to the mode of DEST.  So indicate that.  */
        if (GET_CODE (dest) == SUBREG
            && GET_MODE_SIZE (GET_MODE (dest)) <= UNITS_PER_WORD
            && GET_MODE_SIZE (GET_MODE (SUBREG_REG (dest))) <= UNITS_PER_WORD
            && (GET_MODE_SIZE (GET_MODE (SUBREG_REG (dest)))
                      <= GET_MODE_SIZE (GET_MODE (dest)))
            && (tem = gen_lowpart_if_possible (GET_MODE (dest), src)))
          src = tem, dest = SUBREG_REG (dest);

        /* If storing a recognizable value save it for later recording.  */
        if ((map->num_sets < MAX_RECOG_OPERANDS)
            && (CONSTANT_P (src)
                || (GET_CODE (src) == PLUS
                    && GET_CODE (XEXP (src, 0)) == REG
                    && REGNO (XEXP (src, 0)) >= FIRST_VIRTUAL_REGISTER
                    && REGNO (XEXP (src, 0)) <= LAST_VIRTUAL_REGISTER
                    && CONSTANT_P (XEXP (src, 1)))
                || GET_CODE (src) == COMPARE
#ifdef HAVE_cc0
                || dest == cc0_rtx
#endif
                || (dest == pc_rtx
                    && (src == pc_rtx || GET_CODE (src) == RETURN
                        || GET_CODE (src) == LABEL_REF))))
          {
            /* Normally, this copy won't do anything.  But, if SRC is a COMPARE
               it will cause us to save the COMPARE with any constants
               substituted, which is what we want for later.  */
            map->equiv_sets[map->num_sets].equiv = copy_rtx (src);
            map->equiv_sets[map->num_sets++].dest = dest;
          }

        return;
      }
    }

  format_ptr = GET_RTX_FORMAT (code);
  
  /* If the first operand is an expression, save its mode for later.  */
  if (*format_ptr == 'e')
    op0_mode = GET_MODE (XEXP (x, 0));

  for (i = 0; i < GET_RTX_LENGTH (code); i++)
    {
      switch (*format_ptr++)
        {
        case '0':
          break;

        case 'e':
          if (XEXP (x, i))
            subst_constants (&XEXP (x, i), insn, map);
          break;

        case 'u':
        case 'i':
        case 's':
          break;

        case 'E':
          if (XVEC (x, i) != NULL && XVECLEN (x, i) != 0)
            {
              int j;
              for (j = 0; j < XVECLEN (x, i); j++)
                subst_constants (&XVECEXP (x, i, j), insn, map);
            }
          break;

        default:
          abort ();
        }
    }

  /* If this is a commutative operation, move a constant to the second
     operand unless the second operand is already a CONST_INT.  */
  if ((GET_RTX_CLASS (code) == 'c' || code == NE || code == EQ)
      && CONSTANT_P (XEXP (x, 0)) && GET_CODE (XEXP (x, 1)) != CONST_INT)
    {
      rtx tem = XEXP (x, 0);
      validate_change (insn, &XEXP (x, 0), XEXP (x, 1), 1);
      validate_change (insn, &XEXP (x, 1), tem, 1);
    }

  /* Simplify the expression in case we put in some constants.  */
  switch (GET_RTX_CLASS (code))
    {
    case '1':
      new = simplify_unary_operation (code, GET_MODE (x),
                                      XEXP (x, 0), op0_mode);
      break;

    case '<':
      {
        enum machine_mode op_mode = GET_MODE (XEXP (x, 0));
        if (op_mode == VOIDmode)
          op_mode = GET_MODE (XEXP (x, 1));
        new = simplify_relational_operation (code, op_mode,
                                             XEXP (x, 0), XEXP (x, 1));
        break;
      }

    case '2':
    case 'c':
      new = simplify_binary_operation (code, GET_MODE (x),
                                       XEXP (x, 0), XEXP (x, 1));
      break;

    case 'b':
    case '3':
      new = simplify_ternary_operation (code, GET_MODE (x), op0_mode,
                                        XEXP (x, 0), XEXP (x, 1), XEXP (x, 2));
      break;
    }

  if (new)
    validate_change (insn, loc, new, 1);
}

/* Show that register modified no longer contain known constants.  We are
   called from note_stores with parts of the new insn.  */

void
mark_stores (dest, x)
     rtx dest;
     rtx x;
{
  if (GET_CODE (dest) == SUBREG)
    dest = SUBREG_REG (dest);

  if (GET_CODE (dest) == REG)
    global_const_equiv_map[REGNO (dest)] = 0;
}
\f
/* If any CONST expressions with RTX_INTEGRATED_P are present in the rtx
   pointed to by PX, they represent constants in the constant pool.
   Replace these with a new memory reference obtained from force_const_mem.
   Similarly, ADDRESS expressions with RTX_INTEGRATED_P represent the
   address of a constant pool entry.  Replace them with the address of
   a new constant pool entry obtained from force_const_mem.  */

static void
restore_constants (px)
     rtx *px;
{
  rtx x = *px;
  int i, j;
  char *fmt;

  if (x == 0)
    return;

  if (GET_CODE (x) == CONST_DOUBLE)
    {
      /* We have to make a new CONST_DOUBLE to ensure that we account for
         it correctly.  Using the old CONST_DOUBLE_MEM data is wrong.  */
      if (GET_MODE_CLASS (GET_MODE (x)) == MODE_FLOAT)
        {
          REAL_VALUE_TYPE d;

          REAL_VALUE_FROM_CONST_DOUBLE (d, x);
          *px = immed_real_const_1 (d, GET_MODE (x));
        }
      else
        *px = immed_double_const (CONST_DOUBLE_LOW (x), CONST_DOUBLE_HIGH (x),
                                  VOIDmode);
    }

  else if (RTX_INTEGRATED_P (x) && GET_CODE (x) == CONST)
    {
      restore_constants (&XEXP (x, 0));
      *px = validize_mem (force_const_mem (GET_MODE (x), XEXP (x, 0)));
    }
  else if (RTX_INTEGRATED_P (x) && GET_CODE (x) == SUBREG)
    {
      /* This must be (subreg/i:M1 (const/i:M2 ...) 0).  */
      rtx new = XEXP (SUBREG_REG (x), 0);

      restore_constants (&new);
      new = force_const_mem (GET_MODE (SUBREG_REG (x)), new);
      PUT_MODE (new, GET_MODE (x));
      *px = validize_mem (new);
    }
  else if (RTX_INTEGRATED_P (x) && GET_CODE (x) == ADDRESS)
    {
      restore_constants (&XEXP (x, 0));
      *px = XEXP (force_const_mem (GET_MODE (x), XEXP (x, 0)), 0);
    }
  else
    {
      fmt = GET_RTX_FORMAT (GET_CODE (x));
      for (i = 0; i < GET_RTX_LENGTH (GET_CODE (x)); i++)
        {
          switch (*fmt++)
            {
            case 'E':
              for (j = 0; j < XVECLEN (x, i); j++)
                restore_constants (&XVECEXP (x, i, j));
              break;

            case 'e':
              restore_constants (&XEXP (x, i));
              break;
            }
        }
    }
}
\f
/* Output the assembly language code for the function FNDECL
   from its DECL_SAVED_INSNS.  Used for inline functions that are output
   at end of compilation instead of where they came in the source.  */

void
output_inline_function (fndecl)
     tree fndecl;
{
  rtx head = DECL_SAVED_INSNS (fndecl);
  rtx last;

  temporary_allocation ();

  current_function_decl = fndecl;

  /* This call is only used to initialize global variables.  */
  init_function_start (fndecl, "lossage", 1);

  /* Redo parameter determinations in case the FUNCTION_...
     macros took machine-specific actions that need to be redone.  */
  assign_parms (fndecl, 1);

  /* Set stack frame size.  */
  assign_stack_local (BLKmode, DECL_FRAME_SIZE (fndecl), 0);

  restore_reg_data (FIRST_PARM_INSN (head));

  stack_slot_list = STACK_SLOT_LIST (head);

  if (FUNCTION_FLAGS (head) & FUNCTION_FLAGS_CALLS_ALLOCA)
    current_function_calls_alloca = 1;

  if (FUNCTION_FLAGS (head) & FUNCTION_FLAGS_CALLS_SETJMP)
    current_function_calls_setjmp = 1;

  if (FUNCTION_FLAGS (head) & FUNCTION_FLAGS_CALLS_LONGJMP)
    current_function_calls_longjmp = 1;

  if (FUNCTION_FLAGS (head) & FUNCTION_FLAGS_RETURNS_STRUCT)
    current_function_returns_struct = 1;

  if (FUNCTION_FLAGS (head) & FUNCTION_FLAGS_RETURNS_PCC_STRUCT)
    current_function_returns_pcc_struct = 1;

  if (FUNCTION_FLAGS (head) & FUNCTION_FLAGS_NEEDS_CONTEXT)
    current_function_needs_context = 1;

  if (FUNCTION_FLAGS (head) & FUNCTION_FLAGS_HAS_NONLOCAL_LABEL)
    current_function_has_nonlocal_label = 1;

  if (FUNCTION_FLAGS (head) & FUNCTION_FLAGS_RETURNS_POINTER)
    current_function_returns_pointer = 1;

  if (FUNCTION_FLAGS (head) & FUNCTION_FLAGS_USES_CONST_POOL)
    current_function_uses_const_pool = 1;

  if (FUNCTION_FLAGS (head) & FUNCTION_FLAGS_USES_PIC_OFFSET_TABLE)
    current_function_uses_pic_offset_table = 1;

  current_function_outgoing_args_size = OUTGOING_ARGS_SIZE (head);
  current_function_pops_args = POPS_ARGS (head);

  /* There is no need to output a return label again.  */
  return_label = 0;

  expand_function_end (DECL_SOURCE_FILE (fndecl), DECL_SOURCE_LINE (fndecl));

  /* Find last insn and rebuild the constant pool.  */
  for (last = FIRST_PARM_INSN (head);
       NEXT_INSN (last); last = NEXT_INSN (last))
    {
      if (GET_RTX_CLASS (GET_CODE (last)) == 'i')
        {
          restore_constants (&PATTERN (last));
          restore_constants (&REG_NOTES (last));
        }
    }

  set_new_first_and_last_insn (FIRST_PARM_INSN (head), last);
  set_new_first_and_last_label_num (FIRST_LABELNO (head), LAST_LABELNO (head));

  /* Compile this function all the way down to assembly code.  */
  rest_of_compilation (fndecl);

  current_function_decl = 0;

  permanent_allocation ();
}