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[PATCH][big but trivial] move regcprop to its own file


I would like to rewrite regrename sooner or later, and one small step is
to separate the two passes in regrename.c.

The patch was generated after "svn cp", so it only shows deleting
regcprop in regrename.c and deleting regrename in regcprop.c.

Bootstrapped i686-pc-linux-gnu (stage2 so far), will regtest before
committing.

Paolo
2009-05-07  Paolo Bonzini  <bonzini@gnu.org>

	* Makefile.in (OBJS-common): Add regcprop.o.
	(regcprop.o): New.
	* timevar.def (TV_CPROP_REGISTERS): New.
	* regrename.c (regrename_optimize): Return 0.
	(rest_of_handle_regrename): Delete.
	(pass_rename_registers): Point to regrename_optimize.
	(struct value_data_entry, struct value_data, 
	kill_value_one_regno, kill_value_regno, kill_value,
	set_value_regno, init_value_data, kill_clobbered_value,
	kill_set_value, kill_autoinc_value, copy_value,
	mode_change_ok, maybe_mode_change, find_oldest_value_reg,
	replace_oldest_value_reg, replace_oldest_value_addr,
	replace_oldest_value_mem, copyprop_hardreg_forward_1,
	debug_value_data, validate_value_data): Move...
	* regcprop.c: ... here.
	(rest_of_handle_cprop): Delete.
	(pass_cprop_hardreg): Point to copyprop_hardreg_forward.

Index: Makefile.in
===================================================================
--- Makefile.in	(revision 147147)
+++ Makefile.in	(working copy)
@@ -1174,6 +1174,7 @@ OBJS-common = \
 	real.o \
 	recog.o \
 	reg-stack.o \
+	regcprop.o \
 	reginfo.o \
 	regmove.o \
 	regrename.o \
@@ -3050,6 +3051,10 @@ cfglayout.o : cfglayout.c $(CONFIG_H) $(
    $(DF_H)
 timevar.o : timevar.c $(CONFIG_H) $(SYSTEM_H) coretypes.h $(TM_H) \
    $(TIMEVAR_H) $(FLAGS_H) intl.h $(TOPLEV_H) $(RTL_H) timevar.def
+regcprop.o : regcprop.c $(CONFIG_H) $(SYSTEM_H) coretypes.h $(TM_H) \
+   $(RTL_H) insn-config.h $(BASIC_BLOCK_H) $(REGS_H) hard-reg-set.h \
+   output.h $(RECOG_H) $(FUNCTION_H) $(OBSTACK_H) $(FLAGS_H) $(TM_P_H) \
+   addresses.h reload.h $(TOPLEV_H) $(TIMEVAR_H) $(TREE_PASS_H) $(DF_H)
 regrename.o : regrename.c $(CONFIG_H) $(SYSTEM_H) coretypes.h $(TM_H) \
    $(RTL_H) insn-config.h $(BASIC_BLOCK_H) $(REGS_H) hard-reg-set.h \
    output.h $(RECOG_H) $(FUNCTION_H) $(OBSTACK_H) $(FLAGS_H) $(TM_P_H) \
Index: timevar.def
===================================================================
--- timevar.def	(revision 147147)
+++ timevar.def	(working copy)
@@ -182,6 +182,7 @@ DEFTIMEVAR (TV_THREAD_PROLOGUE_AND_EPILO
 DEFTIMEVAR (TV_IFCVT2		     , "if-conversion 2")
 DEFTIMEVAR (TV_PEEPHOLE2             , "peephole 2")
 DEFTIMEVAR (TV_RENAME_REGISTERS      , "rename registers")
+DEFTIMEVAR (TV_CPROP_REGISTERS       , "hard reg cprop")
 DEFTIMEVAR (TV_SCHED2                , "scheduling 2")
 DEFTIMEVAR (TV_MACH_DEP              , "machine dep reorg")
 DEFTIMEVAR (TV_DBR_SCHED             , "delay branch sched")
Index: regrename.c
===================================================================
--- regrename.c	(revision 147147)
+++ regrename.c	(working copy)
@@ -180,7 +180,7 @@ merge_overlapping_regs (basic_block b, H
 
 /* Perform register renaming on the current function.  */
 
-static void
+static unsigned int
 regrename_optimize (void)
 {
   int tick[FIRST_PSEUDO_REGISTER];
@@ -355,6 +355,8 @@ regrename_optimize (void)
 
   if (dump_file)
     fputc ('\n', dump_file);
+
+  return 0;
 }
 
 static void
@@ -999,943 +1001,7 @@ dump_def_use_chain (struct du_chain *cha
       chains = chains->next_chain;
     }
 }
-
-/* The following code does forward propagation of hard register copies.
-   The object is to eliminate as many dependencies as possible, so that
-   we have the most scheduling freedom.  As a side effect, we also clean
-   up some silly register allocation decisions made by reload.  This
-   code may be obsoleted by a new register allocator.  */
-
-/* For each register, we have a list of registers that contain the same
-   value.  The OLDEST_REGNO field points to the head of the list, and
-   the NEXT_REGNO field runs through the list.  The MODE field indicates
-   what mode the data is known to be in; this field is VOIDmode when the
-   register is not known to contain valid data.  */
-
-struct value_data_entry
-{
-  enum machine_mode mode;
-  unsigned int oldest_regno;
-  unsigned int next_regno;
-};
-
-struct value_data
-{
-  struct value_data_entry e[FIRST_PSEUDO_REGISTER];
-  unsigned int max_value_regs;
-};
-
-static void kill_value_one_regno (unsigned, struct value_data *);
-static void kill_value_regno (unsigned, unsigned, struct value_data *);
-static void kill_value (rtx, struct value_data *);
-static void set_value_regno (unsigned, enum machine_mode, struct value_data *);
-static void init_value_data (struct value_data *);
-static void kill_clobbered_value (rtx, const_rtx, void *);
-static void kill_set_value (rtx, const_rtx, void *);
-static int kill_autoinc_value (rtx *, void *);
-static void copy_value (rtx, rtx, struct value_data *);
-static bool mode_change_ok (enum machine_mode, enum machine_mode,
-			    unsigned int);
-static rtx maybe_mode_change (enum machine_mode, enum machine_mode,
-			      enum machine_mode, unsigned int, unsigned int);
-static rtx find_oldest_value_reg (enum reg_class, rtx, struct value_data *);
-static bool replace_oldest_value_reg (rtx *, enum reg_class, rtx,
-				      struct value_data *);
-static bool replace_oldest_value_addr (rtx *, enum reg_class,
-				       enum machine_mode, rtx,
-				       struct value_data *);
-static bool replace_oldest_value_mem (rtx, rtx, struct value_data *);
-static bool copyprop_hardreg_forward_1 (basic_block, struct value_data *);
-extern void debug_value_data (struct value_data *);
-#ifdef ENABLE_CHECKING
-static void validate_value_data (struct value_data *);
-#endif
-
-/* Kill register REGNO.  This involves removing it from any value
-   lists, and resetting the value mode to VOIDmode.  This is only a
-   helper function; it does not handle any hard registers overlapping
-   with REGNO.  */
-
-static void
-kill_value_one_regno (unsigned int regno, struct value_data *vd)
-{
-  unsigned int i, next;
-
-  if (vd->e[regno].oldest_regno != regno)
-    {
-      for (i = vd->e[regno].oldest_regno;
-	   vd->e[i].next_regno != regno;
-	   i = vd->e[i].next_regno)
-	continue;
-      vd->e[i].next_regno = vd->e[regno].next_regno;
-    }
-  else if ((next = vd->e[regno].next_regno) != INVALID_REGNUM)
-    {
-      for (i = next; i != INVALID_REGNUM; i = vd->e[i].next_regno)
-	vd->e[i].oldest_regno = next;
-    }
-
-  vd->e[regno].mode = VOIDmode;
-  vd->e[regno].oldest_regno = regno;
-  vd->e[regno].next_regno = INVALID_REGNUM;
-
-#ifdef ENABLE_CHECKING
-  validate_value_data (vd);
-#endif
-}
-
-/* Kill the value in register REGNO for NREGS, and any other registers
-   whose values overlap.  */
-
-static void
-kill_value_regno (unsigned int regno, unsigned int nregs,
-		  struct value_data *vd)
-{
-  unsigned int j;
-
-  /* Kill the value we're told to kill.  */
-  for (j = 0; j < nregs; ++j)
-    kill_value_one_regno (regno + j, vd);
-
-  /* Kill everything that overlapped what we're told to kill.  */
-  if (regno < vd->max_value_regs)
-    j = 0;
-  else
-    j = regno - vd->max_value_regs;
-  for (; j < regno; ++j)
-    {
-      unsigned int i, n;
-      if (vd->e[j].mode == VOIDmode)
-	continue;
-      n = hard_regno_nregs[j][vd->e[j].mode];
-      if (j + n > regno)
-	for (i = 0; i < n; ++i)
-	  kill_value_one_regno (j + i, vd);
-    }
-}
-
-/* Kill X.  This is a convenience function wrapping kill_value_regno
-   so that we mind the mode the register is in.  */
-
-static void
-kill_value (rtx x, struct value_data *vd)
-{
-  rtx orig_rtx = x;
-
-  if (GET_CODE (x) == SUBREG)
-    {
-      x = simplify_subreg (GET_MODE (x), SUBREG_REG (x),
-			   GET_MODE (SUBREG_REG (x)), SUBREG_BYTE (x));
-      if (x == NULL_RTX)
-	x = SUBREG_REG (orig_rtx);
-    }
-  if (REG_P (x))
-    {
-      unsigned int regno = REGNO (x);
-      unsigned int n = hard_regno_nregs[regno][GET_MODE (x)];
-
-      kill_value_regno (regno, n, vd);
-    }
-}
-
-/* Remember that REGNO is valid in MODE.  */
-
-static void
-set_value_regno (unsigned int regno, enum machine_mode mode,
-		 struct value_data *vd)
-{
-  unsigned int nregs;
-
-  vd->e[regno].mode = mode;
-
-  nregs = hard_regno_nregs[regno][mode];
-  if (nregs > vd->max_value_regs)
-    vd->max_value_regs = nregs;
-}
-
-/* Initialize VD such that there are no known relationships between regs.  */
-
-static void
-init_value_data (struct value_data *vd)
-{
-  int i;
-  for (i = 0; i < FIRST_PSEUDO_REGISTER; ++i)
-    {
-      vd->e[i].mode = VOIDmode;
-      vd->e[i].oldest_regno = i;
-      vd->e[i].next_regno = INVALID_REGNUM;
-    }
-  vd->max_value_regs = 0;
-}
-
-/* Called through note_stores.  If X is clobbered, kill its value.  */
-
-static void
-kill_clobbered_value (rtx x, const_rtx set, void *data)
-{
-  struct value_data *const vd = (struct value_data *) data;
-  if (GET_CODE (set) == CLOBBER)
-    kill_value (x, vd);
-}
-
-/* Called through note_stores.  If X is set, not clobbered, kill its
-   current value and install it as the root of its own value list.  */
-
-static void
-kill_set_value (rtx x, const_rtx set, void *data)
-{
-  struct value_data *const vd = (struct value_data *) data;
-  if (GET_CODE (set) != CLOBBER)
-    {
-      kill_value (x, vd);
-      if (REG_P (x))
-	set_value_regno (REGNO (x), GET_MODE (x), vd);
-    }
-}
-
-/* Called through for_each_rtx.  Kill any register used as the base of an
-   auto-increment expression, and install that register as the root of its
-   own value list.  */
-
-static int
-kill_autoinc_value (rtx *px, void *data)
-{
-  rtx x = *px;
-  struct value_data *const vd = (struct value_data *) data;
-
-  if (GET_RTX_CLASS (GET_CODE (x)) == RTX_AUTOINC)
-    {
-      x = XEXP (x, 0);
-      kill_value (x, vd);
-      set_value_regno (REGNO (x), Pmode, vd);
-      return -1;
-    }
-
-  return 0;
-}
 
-/* Assert that SRC has been copied to DEST.  Adjust the data structures
-   to reflect that SRC contains an older copy of the shared value.  */
-
-static void
-copy_value (rtx dest, rtx src, struct value_data *vd)
-{
-  unsigned int dr = REGNO (dest);
-  unsigned int sr = REGNO (src);
-  unsigned int dn, sn;
-  unsigned int i;
-
-  /* ??? At present, it's possible to see noop sets.  It'd be nice if
-     this were cleaned up beforehand...  */
-  if (sr == dr)
-    return;
-
-  /* Do not propagate copies to the stack pointer, as that can leave
-     memory accesses with no scheduling dependency on the stack update.  */
-  if (dr == STACK_POINTER_REGNUM)
-    return;
-
-  /* Likewise with the frame pointer, if we're using one.  */
-  if (frame_pointer_needed && dr == HARD_FRAME_POINTER_REGNUM)
-    return;
-
-  /* Do not propagate copies to fixed or global registers, patterns
-     can be relying to see particular fixed register or users can
-     expect the chosen global register in asm.  */
-  if (fixed_regs[dr] || global_regs[dr])
-    return;
-
-  /* If SRC and DEST overlap, don't record anything.  */
-  dn = hard_regno_nregs[dr][GET_MODE (dest)];
-  sn = hard_regno_nregs[sr][GET_MODE (dest)];
-  if ((dr > sr && dr < sr + sn)
-      || (sr > dr && sr < dr + dn))
-    return;
-
-  /* If SRC had no assigned mode (i.e. we didn't know it was live)
-     assign it now and assume the value came from an input argument
-     or somesuch.  */
-  if (vd->e[sr].mode == VOIDmode)
-    set_value_regno (sr, vd->e[dr].mode, vd);
-
-  /* If we are narrowing the input to a smaller number of hard regs,
-     and it is in big endian, we are really extracting a high part.
-     Since we generally associate a low part of a value with the value itself,
-     we must not do the same for the high part.
-     Note we can still get low parts for the same mode combination through
-     a two-step copy involving differently sized hard regs.
-     Assume hard regs fr* are 32 bits bits each, while r* are 64 bits each:
-     (set (reg:DI r0) (reg:DI fr0))
-     (set (reg:SI fr2) (reg:SI r0))
-     loads the low part of (reg:DI fr0) - i.e. fr1 - into fr2, while:
-     (set (reg:SI fr2) (reg:SI fr0))
-     loads the high part of (reg:DI fr0) into fr2.
-
-     We can't properly represent the latter case in our tables, so don't
-     record anything then.  */
-  else if (sn < (unsigned int) hard_regno_nregs[sr][vd->e[sr].mode]
-	   && (GET_MODE_SIZE (vd->e[sr].mode) > UNITS_PER_WORD
-	       ? WORDS_BIG_ENDIAN : BYTES_BIG_ENDIAN))
-    return;
-
-  /* If SRC had been assigned a mode narrower than the copy, we can't
-     link DEST into the chain, because not all of the pieces of the
-     copy came from oldest_regno.  */
-  else if (sn > (unsigned int) hard_regno_nregs[sr][vd->e[sr].mode])
-    return;
-
-  /* Link DR at the end of the value chain used by SR.  */
-
-  vd->e[dr].oldest_regno = vd->e[sr].oldest_regno;
-
-  for (i = sr; vd->e[i].next_regno != INVALID_REGNUM; i = vd->e[i].next_regno)
-    continue;
-  vd->e[i].next_regno = dr;
-
-#ifdef ENABLE_CHECKING
-  validate_value_data (vd);
-#endif
-}
-
-/* Return true if a mode change from ORIG to NEW is allowed for REGNO.  */
-
-static bool
-mode_change_ok (enum machine_mode orig_mode, enum machine_mode new_mode,
-		unsigned int regno ATTRIBUTE_UNUSED)
-{
-  if (GET_MODE_SIZE (orig_mode) < GET_MODE_SIZE (new_mode))
-    return false;
-
-#ifdef CANNOT_CHANGE_MODE_CLASS
-  return !REG_CANNOT_CHANGE_MODE_P (regno, orig_mode, new_mode);
-#endif
-
-  return true;
-}
-
-/* Register REGNO was originally set in ORIG_MODE.  It - or a copy of it -
-   was copied in COPY_MODE to COPY_REGNO, and then COPY_REGNO was accessed
-   in NEW_MODE.
-   Return a NEW_MODE rtx for REGNO if that's OK, otherwise return NULL_RTX.  */
-
-static rtx
-maybe_mode_change (enum machine_mode orig_mode, enum machine_mode copy_mode,
-		   enum machine_mode new_mode, unsigned int regno,
-		   unsigned int copy_regno ATTRIBUTE_UNUSED)
-{
-  if (GET_MODE_SIZE (copy_mode) < GET_MODE_SIZE (orig_mode)
-      && GET_MODE_SIZE (copy_mode) < GET_MODE_SIZE (new_mode))
-    return NULL_RTX;
-
-  if (orig_mode == new_mode)
-    return gen_rtx_raw_REG (new_mode, regno);
-  else if (mode_change_ok (orig_mode, new_mode, regno))
-    {
-      int copy_nregs = hard_regno_nregs[copy_regno][copy_mode];
-      int use_nregs = hard_regno_nregs[copy_regno][new_mode];
-      int copy_offset
-	= GET_MODE_SIZE (copy_mode) / copy_nregs * (copy_nregs - use_nregs);
-      int offset
-	= GET_MODE_SIZE (orig_mode) - GET_MODE_SIZE (new_mode) - copy_offset;
-      int byteoffset = offset % UNITS_PER_WORD;
-      int wordoffset = offset - byteoffset;
-
-      offset = ((WORDS_BIG_ENDIAN ? wordoffset : 0)
-		+ (BYTES_BIG_ENDIAN ? byteoffset : 0));
-      return gen_rtx_raw_REG (new_mode,
-			      regno + subreg_regno_offset (regno, orig_mode,
-							   offset,
-							   new_mode));
-    }
-  return NULL_RTX;
-}
-
-/* Find the oldest copy of the value contained in REGNO that is in
-   register class CL and has mode MODE.  If found, return an rtx
-   of that oldest register, otherwise return NULL.  */
-
-static rtx
-find_oldest_value_reg (enum reg_class cl, rtx reg, struct value_data *vd)
-{
-  unsigned int regno = REGNO (reg);
-  enum machine_mode mode = GET_MODE (reg);
-  unsigned int i;
-
-  /* If we are accessing REG in some mode other that what we set it in,
-     make sure that the replacement is valid.  In particular, consider
-	(set (reg:DI r11) (...))
-	(set (reg:SI r9) (reg:SI r11))
-	(set (reg:SI r10) (...))
-	(set (...) (reg:DI r9))
-     Replacing r9 with r11 is invalid.  */
-  if (mode != vd->e[regno].mode)
-    {
-      if (hard_regno_nregs[regno][mode]
-	  > hard_regno_nregs[regno][vd->e[regno].mode])
-	return NULL_RTX;
-    }
-
-  for (i = vd->e[regno].oldest_regno; i != regno; i = vd->e[i].next_regno)
-    {
-      enum machine_mode oldmode = vd->e[i].mode;
-      rtx new_rtx;
-
-      if (!in_hard_reg_set_p (reg_class_contents[cl], mode, i))
-	return NULL_RTX;
-
-      new_rtx = maybe_mode_change (oldmode, vd->e[regno].mode, mode, i, regno);
-      if (new_rtx)
-	{
-	  ORIGINAL_REGNO (new_rtx) = ORIGINAL_REGNO (reg);
-	  REG_ATTRS (new_rtx) = REG_ATTRS (reg);
-	  REG_POINTER (new_rtx) = REG_POINTER (reg);
-	  return new_rtx;
-	}
-    }
-
-  return NULL_RTX;
-}
-
-/* If possible, replace the register at *LOC with the oldest register
-   in register class CL.  Return true if successfully replaced.  */
-
-static bool
-replace_oldest_value_reg (rtx *loc, enum reg_class cl, rtx insn,
-			  struct value_data *vd)
-{
-  rtx new_rtx = find_oldest_value_reg (cl, *loc, vd);
-  if (new_rtx)
-    {
-      if (dump_file)
-	fprintf (dump_file, "insn %u: replaced reg %u with %u\n",
-		 INSN_UID (insn), REGNO (*loc), REGNO (new_rtx));
-
-      validate_change (insn, loc, new_rtx, 1);
-      return true;
-    }
-  return false;
-}
-
-/* Similar to replace_oldest_value_reg, but *LOC contains an address.
-   Adapted from find_reloads_address_1.  CL is INDEX_REG_CLASS or
-   BASE_REG_CLASS depending on how the register is being considered.  */
-
-static bool
-replace_oldest_value_addr (rtx *loc, enum reg_class cl,
-			   enum machine_mode mode, rtx insn,
-			   struct value_data *vd)
-{
-  rtx x = *loc;
-  RTX_CODE code = GET_CODE (x);
-  const char *fmt;
-  int i, j;
-  bool changed = false;
-
-  switch (code)
-    {
-    case PLUS:
-      {
-	rtx orig_op0 = XEXP (x, 0);
-	rtx orig_op1 = XEXP (x, 1);
-	RTX_CODE code0 = GET_CODE (orig_op0);
-	RTX_CODE code1 = GET_CODE (orig_op1);
-	rtx op0 = orig_op0;
-	rtx op1 = orig_op1;
-	rtx *locI = NULL;
-	rtx *locB = NULL;
-	enum rtx_code index_code = SCRATCH;
-
-	if (GET_CODE (op0) == SUBREG)
-	  {
-	    op0 = SUBREG_REG (op0);
-	    code0 = GET_CODE (op0);
-	  }
-
-	if (GET_CODE (op1) == SUBREG)
-	  {
-	    op1 = SUBREG_REG (op1);
-	    code1 = GET_CODE (op1);
-	  }
-
-	if (code0 == MULT || code0 == SIGN_EXTEND || code0 == TRUNCATE
-	    || code0 == ZERO_EXTEND || code1 == MEM)
-	  {
-	    locI = &XEXP (x, 0);
-	    locB = &XEXP (x, 1);
-	    index_code = GET_CODE (*locI);
-	  }
-	else if (code1 == MULT || code1 == SIGN_EXTEND || code1 == TRUNCATE
-		 || code1 == ZERO_EXTEND || code0 == MEM)
-	  {
-	    locI = &XEXP (x, 1);
-	    locB = &XEXP (x, 0);
-	    index_code = GET_CODE (*locI);
-	  }
-	else if (code0 == CONST_INT || code0 == CONST
-		 || code0 == SYMBOL_REF || code0 == LABEL_REF)
-	  {
-	    locB = &XEXP (x, 1);
-	    index_code = GET_CODE (XEXP (x, 0));
-	  }
-	else if (code1 == CONST_INT || code1 == CONST
-		 || code1 == SYMBOL_REF || code1 == LABEL_REF)
-	  {
-	    locB = &XEXP (x, 0);
-	    index_code = GET_CODE (XEXP (x, 1));
-	  }
-	else if (code0 == REG && code1 == REG)
-	  {
-	    int index_op;
-	    unsigned regno0 = REGNO (op0), regno1 = REGNO (op1);
-
-	    if (REGNO_OK_FOR_INDEX_P (regno1)
-		&& regno_ok_for_base_p (regno0, mode, PLUS, REG))
-	      index_op = 1;
-	    else if (REGNO_OK_FOR_INDEX_P (regno0)
-		     && regno_ok_for_base_p (regno1, mode, PLUS, REG))
-	      index_op = 0;
-	    else if (regno_ok_for_base_p (regno0, mode, PLUS, REG)
-		     || REGNO_OK_FOR_INDEX_P (regno1))
-	      index_op = 1;
-	    else if (regno_ok_for_base_p (regno1, mode, PLUS, REG))
-	      index_op = 0;
-	    else
-	      index_op = 1;
-
-	    locI = &XEXP (x, index_op);
-	    locB = &XEXP (x, !index_op);
-	    index_code = GET_CODE (*locI);
-	  }
-	else if (code0 == REG)
-	  {
-	    locI = &XEXP (x, 0);
-	    locB = &XEXP (x, 1);
-	    index_code = GET_CODE (*locI);
-	  }
-	else if (code1 == REG)
-	  {
-	    locI = &XEXP (x, 1);
-	    locB = &XEXP (x, 0);
-	    index_code = GET_CODE (*locI);
-	  }
-
-	if (locI)
-	  changed |= replace_oldest_value_addr (locI, INDEX_REG_CLASS, mode,
-						insn, vd);
-	if (locB)
-	  changed |= replace_oldest_value_addr (locB,
-						base_reg_class (mode, PLUS,
-								index_code),
-						mode, insn, vd);
-	return changed;
-      }
-
-    case POST_INC:
-    case POST_DEC:
-    case POST_MODIFY:
-    case PRE_INC:
-    case PRE_DEC:
-    case PRE_MODIFY:
-      return false;
-
-    case MEM:
-      return replace_oldest_value_mem (x, insn, vd);
-
-    case REG:
-      return replace_oldest_value_reg (loc, cl, insn, vd);
-
-    default:
-      break;
-    }
-
-  fmt = GET_RTX_FORMAT (code);
-  for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
-    {
-      if (fmt[i] == 'e')
-	changed |= replace_oldest_value_addr (&XEXP (x, i), cl, mode,
-					      insn, vd);
-      else if (fmt[i] == 'E')
-	for (j = XVECLEN (x, i) - 1; j >= 0; j--)
-	  changed |= replace_oldest_value_addr (&XVECEXP (x, i, j), cl,
-						mode, insn, vd);
-    }
-
-  return changed;
-}
-
-/* Similar to replace_oldest_value_reg, but X contains a memory.  */
-
-static bool
-replace_oldest_value_mem (rtx x, rtx insn, struct value_data *vd)
-{
-  return replace_oldest_value_addr (&XEXP (x, 0),
-				    base_reg_class (GET_MODE (x), MEM,
-						    SCRATCH),
-				    GET_MODE (x), insn, vd);
-}
-
-/* Perform the forward copy propagation on basic block BB.  */
-
-static bool
-copyprop_hardreg_forward_1 (basic_block bb, struct value_data *vd)
-{
-  bool changed = false;
-  rtx insn;
-
-  for (insn = BB_HEAD (bb); ; insn = NEXT_INSN (insn))
-    {
-      int n_ops, i, alt, predicated;
-      bool is_asm, any_replacements;
-      rtx set;
-      bool replaced[MAX_RECOG_OPERANDS];
-
-      if (! INSN_P (insn))
-	{
-	  if (insn == BB_END (bb))
-	    break;
-	  else
-	    continue;
-	}
-
-      set = single_set (insn);
-      extract_insn (insn);
-      if (! constrain_operands (1))
-	fatal_insn_not_found (insn);
-      preprocess_constraints ();
-      alt = which_alternative;
-      n_ops = recog_data.n_operands;
-      is_asm = asm_noperands (PATTERN (insn)) >= 0;
-
-      /* Simplify the code below by rewriting things to reflect
-	 matching constraints.  Also promote OP_OUT to OP_INOUT
-	 in predicated instructions.  */
-
-      predicated = GET_CODE (PATTERN (insn)) == COND_EXEC;
-      for (i = 0; i < n_ops; ++i)
-	{
-	  int matches = recog_op_alt[i][alt].matches;
-	  if (matches >= 0)
-	    recog_op_alt[i][alt].cl = recog_op_alt[matches][alt].cl;
-	  if (matches >= 0 || recog_op_alt[i][alt].matched >= 0
-	      || (predicated && recog_data.operand_type[i] == OP_OUT))
-	    recog_data.operand_type[i] = OP_INOUT;
-	}
-
-      /* For each earlyclobber operand, zap the value data.  */
-      for (i = 0; i < n_ops; i++)
-	if (recog_op_alt[i][alt].earlyclobber)
-	  kill_value (recog_data.operand[i], vd);
-
-      /* Within asms, a clobber cannot overlap inputs or outputs.
-	 I wouldn't think this were true for regular insns, but
-	 scan_rtx treats them like that...  */
-      note_stores (PATTERN (insn), kill_clobbered_value, vd);
-
-      /* Kill all auto-incremented values.  */
-      /* ??? REG_INC is useless, since stack pushes aren't done that way.  */
-      for_each_rtx (&PATTERN (insn), kill_autoinc_value, vd);
-
-      /* Kill all early-clobbered operands.  */
-      for (i = 0; i < n_ops; i++)
-	if (recog_op_alt[i][alt].earlyclobber)
-	  kill_value (recog_data.operand[i], vd);
-
-      /* Special-case plain move instructions, since we may well
-	 be able to do the move from a different register class.  */
-      if (set && REG_P (SET_SRC (set)))
-	{
-	  rtx src = SET_SRC (set);
-	  unsigned int regno = REGNO (src);
-	  enum machine_mode mode = GET_MODE (src);
-	  unsigned int i;
-	  rtx new_rtx;
-
-	  /* If we are accessing SRC in some mode other that what we
-	     set it in, make sure that the replacement is valid.  */
-	  if (mode != vd->e[regno].mode)
-	    {
-	      if (hard_regno_nregs[regno][mode]
-		  > hard_regno_nregs[regno][vd->e[regno].mode])
-		goto no_move_special_case;
-	    }
-
-	  /* If the destination is also a register, try to find a source
-	     register in the same class.  */
-	  if (REG_P (SET_DEST (set)))
-	    {
-	      new_rtx = find_oldest_value_reg (REGNO_REG_CLASS (regno), src, vd);
-	      if (new_rtx && validate_change (insn, &SET_SRC (set), new_rtx, 0))
-		{
-		  if (dump_file)
-		    fprintf (dump_file,
-			     "insn %u: replaced reg %u with %u\n",
-			     INSN_UID (insn), regno, REGNO (new_rtx));
-		  changed = true;
-		  goto did_replacement;
-		}
-	    }
-
-	  /* Otherwise, try all valid registers and see if its valid.  */
-	  for (i = vd->e[regno].oldest_regno; i != regno;
-	       i = vd->e[i].next_regno)
-	    {
-	      new_rtx = maybe_mode_change (vd->e[i].mode, vd->e[regno].mode,
-				       mode, i, regno);
-	      if (new_rtx != NULL_RTX)
-		{
-		  if (validate_change (insn, &SET_SRC (set), new_rtx, 0))
-		    {
-		      ORIGINAL_REGNO (new_rtx) = ORIGINAL_REGNO (src);
-		      REG_ATTRS (new_rtx) = REG_ATTRS (src);
-		      REG_POINTER (new_rtx) = REG_POINTER (src);
-		      if (dump_file)
-			fprintf (dump_file,
-				 "insn %u: replaced reg %u with %u\n",
-				 INSN_UID (insn), regno, REGNO (new_rtx));
-		      changed = true;
-		      goto did_replacement;
-		    }
-		}
-	    }
-	}
-      no_move_special_case:
-
-      any_replacements = false;
-
-      /* For each input operand, replace a hard register with the
-	 eldest live copy that's in an appropriate register class.  */
-      for (i = 0; i < n_ops; i++)
-	{
-	  replaced[i] = false;
-
-	  /* Don't scan match_operand here, since we've no reg class
-	     information to pass down.  Any operands that we could
-	     substitute in will be represented elsewhere.  */
-	  if (recog_data.constraints[i][0] == '\0')
-	    continue;
-
-	  /* Don't replace in asms intentionally referencing hard regs.  */
-	  if (is_asm && REG_P (recog_data.operand[i])
-	      && (REGNO (recog_data.operand[i])
-		  == ORIGINAL_REGNO (recog_data.operand[i])))
-	    continue;
-
-	  if (recog_data.operand_type[i] == OP_IN)
-	    {
-	      if (recog_op_alt[i][alt].is_address)
-		replaced[i]
-		  = replace_oldest_value_addr (recog_data.operand_loc[i],
-					       recog_op_alt[i][alt].cl,
-					       VOIDmode, insn, vd);
-	      else if (REG_P (recog_data.operand[i]))
-		replaced[i]
-		  = replace_oldest_value_reg (recog_data.operand_loc[i],
-					      recog_op_alt[i][alt].cl,
-					      insn, vd);
-	      else if (MEM_P (recog_data.operand[i]))
-		replaced[i] = replace_oldest_value_mem (recog_data.operand[i],
-							insn, vd);
-	    }
-	  else if (MEM_P (recog_data.operand[i]))
-	    replaced[i] = replace_oldest_value_mem (recog_data.operand[i],
-						    insn, vd);
-
-	  /* If we performed any replacement, update match_dups.  */
-	  if (replaced[i])
-	    {
-	      int j;
-	      rtx new_rtx;
-
-	      new_rtx = *recog_data.operand_loc[i];
-	      recog_data.operand[i] = new_rtx;
-	      for (j = 0; j < recog_data.n_dups; j++)
-		if (recog_data.dup_num[j] == i)
-		  validate_unshare_change (insn, recog_data.dup_loc[j], new_rtx, 1);
-
-	      any_replacements = true;
-	    }
-	}
-
-      if (any_replacements)
-	{
-	  if (! apply_change_group ())
-	    {
-	      for (i = 0; i < n_ops; i++)
-		if (replaced[i])
-		  {
-		    rtx old = *recog_data.operand_loc[i];
-		    recog_data.operand[i] = old;
-		  }
-
-	      if (dump_file)
-		fprintf (dump_file,
-			 "insn %u: reg replacements not verified\n",
-			 INSN_UID (insn));
-	    }
-	  else
-	    changed = true;
-	}
-
-    did_replacement:
-      /* Clobber call-clobbered registers.  */
-      if (CALL_P (insn))
-	for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
-	  if (TEST_HARD_REG_BIT (regs_invalidated_by_call, i))
-	    kill_value_regno (i, 1, vd);
-
-      /* Notice stores.  */
-      note_stores (PATTERN (insn), kill_set_value, vd);
-
-      /* Notice copies.  */
-      if (set && REG_P (SET_DEST (set)) && REG_P (SET_SRC (set)))
-	copy_value (SET_DEST (set), SET_SRC (set), vd);
-
-      if (insn == BB_END (bb))
-	break;
-    }
-
-  return changed;
-}
-
-/* Main entry point for the forward copy propagation optimization.  */
-
-static void
-copyprop_hardreg_forward (void)
-{
-  struct value_data *all_vd;
-  basic_block bb;
-  sbitmap visited;
-
-  all_vd = XNEWVEC (struct value_data, last_basic_block);
-
-  visited = sbitmap_alloc (last_basic_block);
-  sbitmap_zero (visited);
-
-  FOR_EACH_BB (bb)
-    {
-      SET_BIT (visited, bb->index);
-
-      /* If a block has a single predecessor, that we've already
-	 processed, begin with the value data that was live at
-	 the end of the predecessor block.  */
-      /* ??? Ought to use more intelligent queuing of blocks.  */
-      if (single_pred_p (bb) 
-	  && TEST_BIT (visited, single_pred (bb)->index)
-	  && ! (single_pred_edge (bb)->flags & (EDGE_ABNORMAL_CALL | EDGE_EH)))
-	all_vd[bb->index] = all_vd[single_pred (bb)->index];
-      else
-	init_value_data (all_vd + bb->index);
-
-      copyprop_hardreg_forward_1 (bb, all_vd + bb->index);
-    }
-
-  sbitmap_free (visited);  
-  free (all_vd);
-}
-
-/* Dump the value chain data to stderr.  */
-
-void
-debug_value_data (struct value_data *vd)
-{
-  HARD_REG_SET set;
-  unsigned int i, j;
-
-  CLEAR_HARD_REG_SET (set);
-
-  for (i = 0; i < FIRST_PSEUDO_REGISTER; ++i)
-    if (vd->e[i].oldest_regno == i)
-      {
-	if (vd->e[i].mode == VOIDmode)
-	  {
-	    if (vd->e[i].next_regno != INVALID_REGNUM)
-	      fprintf (stderr, "[%u] Bad next_regno for empty chain (%u)\n",
-		       i, vd->e[i].next_regno);
-	    continue;
-	  }
-
-	SET_HARD_REG_BIT (set, i);
-	fprintf (stderr, "[%u %s] ", i, GET_MODE_NAME (vd->e[i].mode));
-
-	for (j = vd->e[i].next_regno;
-	     j != INVALID_REGNUM;
-	     j = vd->e[j].next_regno)
-	  {
-	    if (TEST_HARD_REG_BIT (set, j))
-	      {
-		fprintf (stderr, "[%u] Loop in regno chain\n", j);
-		return;
-	      }
-
-	    if (vd->e[j].oldest_regno != i)
-	      {
-		fprintf (stderr, "[%u] Bad oldest_regno (%u)\n",
-			 j, vd->e[j].oldest_regno);
-		return;
-	      }
-	    SET_HARD_REG_BIT (set, j);
-	    fprintf (stderr, "[%u %s] ", j, GET_MODE_NAME (vd->e[j].mode));
-	  }
-	fputc ('\n', stderr);
-      }
-
-  for (i = 0; i < FIRST_PSEUDO_REGISTER; ++i)
-    if (! TEST_HARD_REG_BIT (set, i)
-	&& (vd->e[i].mode != VOIDmode
-	    || vd->e[i].oldest_regno != i
-	    || vd->e[i].next_regno != INVALID_REGNUM))
-      fprintf (stderr, "[%u] Non-empty reg in chain (%s %u %i)\n",
-	       i, GET_MODE_NAME (vd->e[i].mode), vd->e[i].oldest_regno,
-	       vd->e[i].next_regno);
-}
-
-#ifdef ENABLE_CHECKING
-static void
-validate_value_data (struct value_data *vd)
-{
-  HARD_REG_SET set;
-  unsigned int i, j;
-
-  CLEAR_HARD_REG_SET (set);
-
-  for (i = 0; i < FIRST_PSEUDO_REGISTER; ++i)
-    if (vd->e[i].oldest_regno == i)
-      {
-	if (vd->e[i].mode == VOIDmode)
-	  {
-	    if (vd->e[i].next_regno != INVALID_REGNUM)
-	      internal_error ("validate_value_data: [%u] Bad next_regno for empty chain (%u)",
-			      i, vd->e[i].next_regno);
-	    continue;
-	  }
-
-	SET_HARD_REG_BIT (set, i);
-
-	for (j = vd->e[i].next_regno;
-	     j != INVALID_REGNUM;
-	     j = vd->e[j].next_regno)
-	  {
-	    if (TEST_HARD_REG_BIT (set, j))
-	      internal_error ("validate_value_data: Loop in regno chain (%u)",
-			      j);
-	    if (vd->e[j].oldest_regno != i)
-	      internal_error ("validate_value_data: [%u] Bad oldest_regno (%u)",
-			      j, vd->e[j].oldest_regno);
-
-	    SET_HARD_REG_BIT (set, j);
-	  }
-      }
-
-  for (i = 0; i < FIRST_PSEUDO_REGISTER; ++i)
-    if (! TEST_HARD_REG_BIT (set, i)
-	&& (vd->e[i].mode != VOIDmode
-	    || vd->e[i].oldest_regno != i
-	    || vd->e[i].next_regno != INVALID_REGNUM))
-      internal_error ("validate_value_data: [%u] Non-empty reg in chain (%s %u %i)",
-		      i, GET_MODE_NAME (vd->e[i].mode), vd->e[i].oldest_regno,
-		      vd->e[i].next_regno);
-}
-#endif
 
 static bool
 gate_handle_regrename (void)
@@ -1943,22 +1009,13 @@ gate_handle_regrename (void)
   return (optimize > 0 && (flag_rename_registers));
 }
 
-
-/* Run the regrename and cprop passes.  */
-static unsigned int
-rest_of_handle_regrename (void)
-{
-  regrename_optimize ();
-  return 0;
-}
-
 struct rtl_opt_pass pass_regrename =
 {
  {
   RTL_PASS,
   "rnreg",                              /* name */
   gate_handle_regrename,                /* gate */
-  rest_of_handle_regrename,             /* execute */
+  regrename_optimize,                   /* execute */
   NULL,                                 /* sub */
   NULL,                                 /* next */
   0,                                    /* static_pass_number */
@@ -1972,36 +1029,3 @@ struct rtl_opt_pass pass_regrename =
  }
 };
 
-static bool
-gate_handle_cprop (void)
-{
-  return (optimize > 0 && (flag_cprop_registers));
-}
-
-
-/* Run the regrename and cprop passes.  */
-static unsigned int
-rest_of_handle_cprop (void)
-{
-  copyprop_hardreg_forward ();
-  return 0;
-}
-
-struct rtl_opt_pass pass_cprop_hardreg =
-{
- {
-  RTL_PASS,
-  "cprop_hardreg",                      /* name */
-  gate_handle_cprop,                    /* gate */
-  rest_of_handle_cprop,                 /* execute */
-  NULL,                                 /* sub */
-  NULL,                                 /* next */
-  0,                                    /* static_pass_number */
-  TV_RENAME_REGISTERS,                  /* tv_id */
-  0,                                    /* properties_required */
-  0,                                    /* properties_provided */
-  0,                                    /* properties_destroyed */
-  0,                                    /* todo_flags_start */
-  TODO_dump_func | TODO_verify_rtl_sharing /* todo_flags_finish */
- }
-};
Index: regcprop.c
===================================================================
--- regcprop.c	(revision 147147)
+++ regcprop.c	(working copy)
@@ -1,4 +1,4 @@
-/* Register renaming for the GNU compiler.
+/* Copy propagation on hard registers for the GNU compiler.
    Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
    Free Software Foundation, Inc.
 
@@ -40,966 +40,6 @@
 #include "tree-pass.h"
 #include "df.h"
 
-struct du_chain
-{
-  struct du_chain *next_chain;
-  struct du_chain *next_use;
-
-  rtx insn;
-  rtx *loc;
-  ENUM_BITFIELD(reg_class) cl : 16;
-  unsigned int need_caller_save_reg:1;
-  unsigned int earlyclobber:1;
-};
-
-enum scan_actions
-{
-  terminate_all_read,
-  terminate_overlapping_read,
-  terminate_write,
-  terminate_dead,
-  mark_read,
-  mark_write,
-  /* mark_access is for marking the destination regs in
-     REG_FRAME_RELATED_EXPR notes (as if they were read) so that the
-     note is updated properly.  */
-  mark_access
-};
-
-static const char * const scan_actions_name[] =
-{
-  "terminate_all_read",
-  "terminate_overlapping_read",
-  "terminate_write",
-  "terminate_dead",
-  "mark_read",
-  "mark_write",
-  "mark_access"
-};
-
-static struct obstack rename_obstack;
-
-static void do_replace (struct du_chain *, int);
-static void scan_rtx_reg (rtx, rtx *, enum reg_class,
-			  enum scan_actions, enum op_type, int);
-static void scan_rtx_address (rtx, rtx *, enum reg_class,
-			      enum scan_actions, enum machine_mode);
-static void scan_rtx (rtx, rtx *, enum reg_class, enum scan_actions,
-		      enum op_type, int);
-static struct du_chain *build_def_use (basic_block);
-static void dump_def_use_chain (struct du_chain *);
-static void note_sets (rtx, const_rtx, void *);
-static void clear_dead_regs (HARD_REG_SET *, enum reg_note, rtx);
-static void merge_overlapping_regs (basic_block, HARD_REG_SET *,
-				    struct du_chain *);
-
-/* Called through note_stores.  Find sets of registers, and
-   record them in *DATA (which is actually a HARD_REG_SET *).  */
-
-static void
-note_sets (rtx x, const_rtx set ATTRIBUTE_UNUSED, void *data)
-{
-  HARD_REG_SET *pset = (HARD_REG_SET *) data;
-
-  if (GET_CODE (x) == SUBREG)
-    x = SUBREG_REG (x);
-  if (!REG_P (x))
-    return;
-  /* There must not be pseudos at this point.  */
-  gcc_assert (HARD_REGISTER_P (x));
-  add_to_hard_reg_set (pset, GET_MODE (x), REGNO (x));
-}
-
-/* Clear all registers from *PSET for which a note of kind KIND can be found
-   in the list NOTES.  */
-
-static void
-clear_dead_regs (HARD_REG_SET *pset, enum reg_note kind, rtx notes)
-{
-  rtx note;
-  for (note = notes; note; note = XEXP (note, 1))
-    if (REG_NOTE_KIND (note) == kind && REG_P (XEXP (note, 0)))
-      {
-	rtx reg = XEXP (note, 0);
-	/* There must not be pseudos at this point.  */
-	gcc_assert (HARD_REGISTER_P (reg));
-	remove_from_hard_reg_set (pset, GET_MODE (reg), REGNO (reg));
-      }
-}
-
-/* For a def-use chain CHAIN in basic block B, find which registers overlap
-   its lifetime and set the corresponding bits in *PSET.  */
-
-static void
-merge_overlapping_regs (basic_block b, HARD_REG_SET *pset,
-			struct du_chain *chain)
-{
-  struct du_chain *t = chain;
-  rtx insn;
-  HARD_REG_SET live;
-  df_ref *def_rec;
-
-  REG_SET_TO_HARD_REG_SET (live, df_get_live_in (b));
-  for (def_rec = df_get_artificial_defs (b->index); *def_rec; def_rec++)
-    {
-      df_ref def = *def_rec;
-      if (DF_REF_FLAGS (def) & DF_REF_AT_TOP)
-	SET_HARD_REG_BIT (live, DF_REF_REGNO (def));
-    }
-  insn = BB_HEAD (b);
-  while (t)
-    {
-      /* Search forward until the next reference to the register to be
-	 renamed.  */
-      while (insn != t->insn)
-	{
-	  if (INSN_P (insn))
-	    {
-	      clear_dead_regs (&live, REG_DEAD, REG_NOTES (insn));
-	      note_stores (PATTERN (insn), note_sets, (void *) &live);
-	      /* Only record currently live regs if we are inside the
-		 reg's live range.  */
-	      if (t != chain)
-		IOR_HARD_REG_SET (*pset, live);
-	      clear_dead_regs (&live, REG_UNUSED, REG_NOTES (insn));
-	    }
-	  insn = NEXT_INSN (insn);
-	}
-
-      IOR_HARD_REG_SET (*pset, live);
-
-      /* For the last reference, also merge in all registers set in the
-	 same insn.
-	 @@@ We only have take earlyclobbered sets into account.  */
-      if (! t->next_use)
-	note_stores (PATTERN (insn), note_sets, (void *) pset);
-
-      t = t->next_use;
-    }
-}
-
-/* Perform register renaming on the current function.  */
-
-static void
-regrename_optimize (void)
-{
-  int tick[FIRST_PSEUDO_REGISTER];
-  int this_tick = 0;
-  basic_block bb;
-  char *first_obj;
-
-  df_set_flags (DF_LR_RUN_DCE);
-  df_note_add_problem ();
-  df_analyze ();
-  df_set_flags (DF_DEFER_INSN_RESCAN);
-
-  memset (tick, 0, sizeof tick);
-
-  gcc_obstack_init (&rename_obstack);
-  first_obj = XOBNEWVAR (&rename_obstack, char, 0);
-
-  FOR_EACH_BB (bb)
-    {
-      struct du_chain *all_chains = 0;
-      HARD_REG_SET unavailable;
-      HARD_REG_SET regs_seen;
-
-      CLEAR_HARD_REG_SET (unavailable);
-
-      if (dump_file)
-	fprintf (dump_file, "\nBasic block %d:\n", bb->index);
-
-      all_chains = build_def_use (bb);
-
-      if (dump_file)
-	dump_def_use_chain (all_chains);
-
-      CLEAR_HARD_REG_SET (unavailable);
-      /* Don't clobber traceback for noreturn functions.  */
-      if (frame_pointer_needed)
-	{
-	  add_to_hard_reg_set (&unavailable, Pmode, FRAME_POINTER_REGNUM);
-#if FRAME_POINTER_REGNUM != HARD_FRAME_POINTER_REGNUM
-	  add_to_hard_reg_set (&unavailable, Pmode, HARD_FRAME_POINTER_REGNUM);
-#endif
-	}
-
-      CLEAR_HARD_REG_SET (regs_seen);
-      while (all_chains)
-	{
-	  int new_reg, best_new_reg;
-	  int n_uses;
-	  struct du_chain *this_du = all_chains;
-	  struct du_chain *tmp, *last;
-	  HARD_REG_SET this_unavailable;
-	  int reg = REGNO (*this_du->loc);
-	  int i;
-
-	  all_chains = this_du->next_chain;
-
-	  best_new_reg = reg;
-
-#if 0 /* This just disables optimization opportunities.  */
-	  /* Only rename once we've seen the reg more than once.  */
-	  if (! TEST_HARD_REG_BIT (regs_seen, reg))
-	    {
-	      SET_HARD_REG_BIT (regs_seen, reg);
-	      continue;
-	    }
-#endif
-
-	  if (fixed_regs[reg] || global_regs[reg]
-#if FRAME_POINTER_REGNUM != HARD_FRAME_POINTER_REGNUM
-	      || (frame_pointer_needed && reg == HARD_FRAME_POINTER_REGNUM)
-#else
-	      || (frame_pointer_needed && reg == FRAME_POINTER_REGNUM)
-#endif
-	      )
-	    continue;
-
-	  COPY_HARD_REG_SET (this_unavailable, unavailable);
-
-	  /* Find last entry on chain (which has the need_caller_save bit),
-	     count number of uses, and narrow the set of registers we can
-	     use for renaming.  */
-	  n_uses = 0;
-	  for (last = this_du; last->next_use; last = last->next_use)
-	    {
-	      n_uses++;
-	      IOR_COMPL_HARD_REG_SET (this_unavailable,
-				      reg_class_contents[last->cl]);
-	    }
-	  if (n_uses < 1)
-	    continue;
-
-	  IOR_COMPL_HARD_REG_SET (this_unavailable,
-				  reg_class_contents[last->cl]);
-
-	  if (this_du->need_caller_save_reg)
-	    IOR_HARD_REG_SET (this_unavailable, call_used_reg_set);
-
-	  merge_overlapping_regs (bb, &this_unavailable, this_du);
-
-	  /* Now potential_regs is a reasonable approximation, let's
-	     have a closer look at each register still in there.  */
-	  for (new_reg = 0; new_reg < FIRST_PSEUDO_REGISTER; new_reg++)
-	    {
-	      int nregs = hard_regno_nregs[new_reg][GET_MODE (*this_du->loc)];
-
-	      for (i = nregs - 1; i >= 0; --i)
-	        if (TEST_HARD_REG_BIT (this_unavailable, new_reg + i)
-		    || fixed_regs[new_reg + i]
-		    || global_regs[new_reg + i]
-		    /* Can't use regs which aren't saved by the prologue.  */
-		    || (! df_regs_ever_live_p (new_reg + i)
-			&& ! call_used_regs[new_reg + i])
-#ifdef LEAF_REGISTERS
-		    /* We can't use a non-leaf register if we're in a
-		       leaf function.  */
-		    || (current_function_is_leaf
-			&& !LEAF_REGISTERS[new_reg + i])
-#endif
-#ifdef HARD_REGNO_RENAME_OK
-		    || ! HARD_REGNO_RENAME_OK (reg + i, new_reg + i)
-#endif
-		    )
-		  break;
-	      if (i >= 0)
-		continue;
-
-	      /* See whether it accepts all modes that occur in
-		 definition and uses.  */
-	      for (tmp = this_du; tmp; tmp = tmp->next_use)
-		if (! HARD_REGNO_MODE_OK (new_reg, GET_MODE (*tmp->loc))
-		    || (tmp->need_caller_save_reg
-			&& ! (HARD_REGNO_CALL_PART_CLOBBERED
-			      (reg, GET_MODE (*tmp->loc)))
-			&& (HARD_REGNO_CALL_PART_CLOBBERED
-			    (new_reg, GET_MODE (*tmp->loc)))))
-		  break;
-	      if (! tmp)
-		{
-		  if (tick[best_new_reg] > tick[new_reg])
-		    best_new_reg = new_reg;
-		}
-	    }
-
-	  if (dump_file)
-	    {
-	      fprintf (dump_file, "Register %s in insn %d",
-		       reg_names[reg], INSN_UID (last->insn));
-	      if (last->need_caller_save_reg)
-		fprintf (dump_file, " crosses a call");
-	    }
-
-	  if (best_new_reg == reg)
-	    {
-	      tick[reg] = ++this_tick;
-	      if (dump_file)
-		fprintf (dump_file, "; no available better choice\n");
-	      continue;
-	    }
-
-	  if (dump_file)
-	    fprintf (dump_file, ", renamed as %s\n", reg_names[best_new_reg]);
-
-	  do_replace (this_du, best_new_reg);
-	  tick[best_new_reg] = ++this_tick;
-	  df_set_regs_ever_live (best_new_reg, true);
-	}
-
-      obstack_free (&rename_obstack, first_obj);
-    }
-
-  obstack_free (&rename_obstack, NULL);
-
-  if (dump_file)
-    fputc ('\n', dump_file);
-}
-
-static void
-do_replace (struct du_chain *chain, int reg)
-{
-  while (chain)
-    {
-      unsigned int regno = ORIGINAL_REGNO (*chain->loc);
-      struct reg_attrs * attr = REG_ATTRS (*chain->loc);
-      int reg_ptr = REG_POINTER (*chain->loc);
-
-      *chain->loc = gen_raw_REG (GET_MODE (*chain->loc), reg);
-      if (regno >= FIRST_PSEUDO_REGISTER)
-	ORIGINAL_REGNO (*chain->loc) = regno;
-      REG_ATTRS (*chain->loc) = attr;
-      REG_POINTER (*chain->loc) = reg_ptr;
-      df_insn_rescan (chain->insn);
-      chain = chain->next_use;
-    }
-}
-
-
-static struct du_chain *open_chains;
-static struct du_chain *closed_chains;
-
-static void
-scan_rtx_reg (rtx insn, rtx *loc, enum reg_class cl,
-	      enum scan_actions action, enum op_type type, int earlyclobber)
-{
-  struct du_chain **p;
-  rtx x = *loc;
-  enum machine_mode mode = GET_MODE (x);
-  int this_regno = REGNO (x);
-  int this_nregs = hard_regno_nregs[this_regno][mode];
-
-  if (action == mark_write)
-    {
-      if (type == OP_OUT)
-	{
-	  struct du_chain *this_du = XOBNEW (&rename_obstack, struct du_chain);
-	  this_du->next_use = 0;
-	  this_du->next_chain = open_chains;
-	  this_du->loc = loc;
-	  this_du->insn = insn;
-	  this_du->cl = cl;
-	  this_du->need_caller_save_reg = 0;
-	  this_du->earlyclobber = earlyclobber;
-	  open_chains = this_du;
-	}
-      return;
-    }
-
-  if ((type == OP_OUT) != (action == terminate_write || action == mark_access))
-    return;
-
-  for (p = &open_chains; *p;)
-    {
-      struct du_chain *this_du = *p;
-
-      /* Check if the chain has been terminated if it has then skip to
-	 the next chain.
-
-	 This can happen when we've already appended the location to
-	 the chain in Step 3, but are trying to hide in-out operands
-	 from terminate_write in Step 5.  */
-
-      if (*this_du->loc == cc0_rtx)
-	p = &this_du->next_chain;
-      else
-	{
-	  int regno = REGNO (*this_du->loc);
-	  int nregs = hard_regno_nregs[regno][GET_MODE (*this_du->loc)];
-	  int exact_match = (regno == this_regno && nregs == this_nregs);
-
-	  if (regno + nregs <= this_regno
-	      || this_regno + this_nregs <= regno)
-	    {
-	      p = &this_du->next_chain;
-	      continue;
-	    }
-
-	  if (action == mark_read || action == mark_access)
-	    {
-	      gcc_assert (exact_match);
-
-	      /* ??? Class NO_REGS can happen if the md file makes use of
-		 EXTRA_CONSTRAINTS to match registers.  Which is arguably
-		 wrong, but there we are.  Since we know not what this may
-		 be replaced with, terminate the chain.  */
-	      if (cl != NO_REGS)
-		{
-		  this_du = XOBNEW (&rename_obstack, struct du_chain);
-		  this_du->next_use = 0;
-		  this_du->next_chain = (*p)->next_chain;
-		  this_du->loc = loc;
-		  this_du->insn = insn;
-		  this_du->cl = cl;
-		  this_du->need_caller_save_reg = 0;
-		  while (*p)
-		    p = &(*p)->next_use;
-		  *p = this_du;
-		  return;
-		}
-	    }
-
-	  if (action != terminate_overlapping_read || ! exact_match)
-	    {
-	      struct du_chain *next = this_du->next_chain;
-
-	      /* Whether the terminated chain can be used for renaming
-	         depends on the action and this being an exact match.
-	         In either case, we remove this element from open_chains.  */
-
-	      if ((action == terminate_dead || action == terminate_write)
-		  && exact_match)
-		{
-		  this_du->next_chain = closed_chains;
-		  closed_chains = this_du;
-		  if (dump_file)
-		    fprintf (dump_file,
-			     "Closing chain %s at insn %d (%s)\n",
-			     reg_names[REGNO (*this_du->loc)], INSN_UID (insn),
-			     scan_actions_name[(int) action]);
-		}
-	      else
-		{
-		  if (dump_file)
-		    fprintf (dump_file,
-			     "Discarding chain %s at insn %d (%s)\n",
-			     reg_names[REGNO (*this_du->loc)], INSN_UID (insn),
-			     scan_actions_name[(int) action]);
-		}
-	      *p = next;
-	    }
-	  else
-	    p = &this_du->next_chain;
-	}
-    }
-}
-
-/* Adapted from find_reloads_address_1.  CL is INDEX_REG_CLASS or
-   BASE_REG_CLASS depending on how the register is being considered.  */
-
-static void
-scan_rtx_address (rtx insn, rtx *loc, enum reg_class cl,
-		  enum scan_actions action, enum machine_mode mode)
-{
-  rtx x = *loc;
-  RTX_CODE code = GET_CODE (x);
-  const char *fmt;
-  int i, j;
-
-  if (action == mark_write || action == mark_access)
-    return;
-
-  switch (code)
-    {
-    case PLUS:
-      {
-	rtx orig_op0 = XEXP (x, 0);
-	rtx orig_op1 = XEXP (x, 1);
-	RTX_CODE code0 = GET_CODE (orig_op0);
-	RTX_CODE code1 = GET_CODE (orig_op1);
-	rtx op0 = orig_op0;
-	rtx op1 = orig_op1;
-	rtx *locI = NULL;
-	rtx *locB = NULL;
-	enum rtx_code index_code = SCRATCH;
-
-	if (GET_CODE (op0) == SUBREG)
-	  {
-	    op0 = SUBREG_REG (op0);
-	    code0 = GET_CODE (op0);
-	  }
-
-	if (GET_CODE (op1) == SUBREG)
-	  {
-	    op1 = SUBREG_REG (op1);
-	    code1 = GET_CODE (op1);
-	  }
-
-	if (code0 == MULT || code0 == SIGN_EXTEND || code0 == TRUNCATE
-	    || code0 == ZERO_EXTEND || code1 == MEM)
-	  {
-	    locI = &XEXP (x, 0);
-	    locB = &XEXP (x, 1);
-	    index_code = GET_CODE (*locI);
-	  }
-	else if (code1 == MULT || code1 == SIGN_EXTEND || code1 == TRUNCATE
-		 || code1 == ZERO_EXTEND || code0 == MEM)
-	  {
-	    locI = &XEXP (x, 1);
-	    locB = &XEXP (x, 0);
-	    index_code = GET_CODE (*locI);
-	  }
-	else if (code0 == CONST_INT || code0 == CONST
-		 || code0 == SYMBOL_REF || code0 == LABEL_REF)
-	  {
-	    locB = &XEXP (x, 1);
-	    index_code = GET_CODE (XEXP (x, 0));
-	  }
-	else if (code1 == CONST_INT || code1 == CONST
-		 || code1 == SYMBOL_REF || code1 == LABEL_REF)
-	  {
-	    locB = &XEXP (x, 0);
-	    index_code = GET_CODE (XEXP (x, 1));
-	  }
-	else if (code0 == REG && code1 == REG)
-	  {
-	    int index_op;
-	    unsigned regno0 = REGNO (op0), regno1 = REGNO (op1);
-
-	    if (REGNO_OK_FOR_INDEX_P (regno1)
-		&& regno_ok_for_base_p (regno0, mode, PLUS, REG))
-	      index_op = 1;
-	    else if (REGNO_OK_FOR_INDEX_P (regno0)
-		     && regno_ok_for_base_p (regno1, mode, PLUS, REG))
-	      index_op = 0;
-	    else if (regno_ok_for_base_p (regno0, mode, PLUS, REG)
-		     || REGNO_OK_FOR_INDEX_P (regno1))
-	      index_op = 1;
-	    else if (regno_ok_for_base_p (regno1, mode, PLUS, REG))
-	      index_op = 0;
-	    else
-	      index_op = 1;
-
-	    locI = &XEXP (x, index_op);
-	    locB = &XEXP (x, !index_op);
-	    index_code = GET_CODE (*locI);
-	  }
-	else if (code0 == REG)
-	  {
-	    locI = &XEXP (x, 0);
-	    locB = &XEXP (x, 1);
-	    index_code = GET_CODE (*locI);
-	  }
-	else if (code1 == REG)
-	  {
-	    locI = &XEXP (x, 1);
-	    locB = &XEXP (x, 0);
-	    index_code = GET_CODE (*locI);
-	  }
-
-	if (locI)
-	  scan_rtx_address (insn, locI, INDEX_REG_CLASS, action, mode);
-	if (locB)
-	  scan_rtx_address (insn, locB, base_reg_class (mode, PLUS, index_code),
-			    action, mode);
-
-	return;
-      }
-
-    case POST_INC:
-    case POST_DEC:
-    case POST_MODIFY:
-    case PRE_INC:
-    case PRE_DEC:
-    case PRE_MODIFY:
-#ifndef AUTO_INC_DEC
-      /* If the target doesn't claim to handle autoinc, this must be
-	 something special, like a stack push.  Kill this chain.  */
-      action = terminate_all_read;
-#endif
-      break;
-
-    case MEM:
-      scan_rtx_address (insn, &XEXP (x, 0),
-			base_reg_class (GET_MODE (x), MEM, SCRATCH), action,
-			GET_MODE (x));
-      return;
-
-    case REG:
-      scan_rtx_reg (insn, loc, cl, action, OP_IN, 0);
-      return;
-
-    default:
-      break;
-    }
-
-  fmt = GET_RTX_FORMAT (code);
-  for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
-    {
-      if (fmt[i] == 'e')
-	scan_rtx_address (insn, &XEXP (x, i), cl, action, mode);
-      else if (fmt[i] == 'E')
-	for (j = XVECLEN (x, i) - 1; j >= 0; j--)
-	  scan_rtx_address (insn, &XVECEXP (x, i, j), cl, action, mode);
-    }
-}
-
-static void
-scan_rtx (rtx insn, rtx *loc, enum reg_class cl,
-	  enum scan_actions action, enum op_type type, int earlyclobber)
-{
-  const char *fmt;
-  rtx x = *loc;
-  enum rtx_code code = GET_CODE (x);
-  int i, j;
-
-  code = GET_CODE (x);
-  switch (code)
-    {
-    case CONST:
-    case CONST_INT:
-    case CONST_DOUBLE:
-    case CONST_FIXED:
-    case CONST_VECTOR:
-    case SYMBOL_REF:
-    case LABEL_REF:
-    case CC0:
-    case PC:
-      return;
-
-    case REG:
-      scan_rtx_reg (insn, loc, cl, action, type, earlyclobber);
-      return;
-
-    case MEM:
-      scan_rtx_address (insn, &XEXP (x, 0),
-			base_reg_class (GET_MODE (x), MEM, SCRATCH), action,
-			GET_MODE (x));
-      return;
-
-    case SET:
-      scan_rtx (insn, &SET_SRC (x), cl, action, OP_IN, 0);
-      scan_rtx (insn, &SET_DEST (x), cl, action,
-		GET_CODE (PATTERN (insn)) == COND_EXEC ? OP_INOUT : OP_OUT, 0);
-      return;
-
-    case STRICT_LOW_PART:
-      scan_rtx (insn, &XEXP (x, 0), cl, action, OP_INOUT, earlyclobber);
-      return;
-
-    case ZERO_EXTRACT:
-    case SIGN_EXTRACT:
-      scan_rtx (insn, &XEXP (x, 0), cl, action,
-		type == OP_IN ? OP_IN : OP_INOUT, earlyclobber);
-      scan_rtx (insn, &XEXP (x, 1), cl, action, OP_IN, 0);
-      scan_rtx (insn, &XEXP (x, 2), cl, action, OP_IN, 0);
-      return;
-
-    case POST_INC:
-    case PRE_INC:
-    case POST_DEC:
-    case PRE_DEC:
-    case POST_MODIFY:
-    case PRE_MODIFY:
-      /* Should only happen inside MEM.  */
-      gcc_unreachable ();
-
-    case CLOBBER:
-      scan_rtx (insn, &SET_DEST (x), cl, action,
-		GET_CODE (PATTERN (insn)) == COND_EXEC ? OP_INOUT : OP_OUT, 0);
-      return;
-
-    case EXPR_LIST:
-      scan_rtx (insn, &XEXP (x, 0), cl, action, type, 0);
-      if (XEXP (x, 1))
-	scan_rtx (insn, &XEXP (x, 1), cl, action, type, 0);
-      return;
-
-    default:
-      break;
-    }
-
-  fmt = GET_RTX_FORMAT (code);
-  for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
-    {
-      if (fmt[i] == 'e')
-	scan_rtx (insn, &XEXP (x, i), cl, action, type, 0);
-      else if (fmt[i] == 'E')
-	for (j = XVECLEN (x, i) - 1; j >= 0; j--)
-	  scan_rtx (insn, &XVECEXP (x, i, j), cl, action, type, 0);
-    }
-}
-
-/* Build def/use chain.  */
-
-static struct du_chain *
-build_def_use (basic_block bb)
-{
-  rtx insn;
-
-  open_chains = closed_chains = NULL;
-
-  for (insn = BB_HEAD (bb); ; insn = NEXT_INSN (insn))
-    {
-      if (INSN_P (insn))
-	{
-	  int n_ops;
-	  rtx note;
-	  rtx old_operands[MAX_RECOG_OPERANDS];
-	  rtx old_dups[MAX_DUP_OPERANDS];
-	  int i, icode;
-	  int alt;
-	  int predicated;
-
-	  /* Process the insn, determining its effect on the def-use
-	     chains.  We perform the following steps with the register
-	     references in the insn:
-	     (1) Any read that overlaps an open chain, but doesn't exactly
-	         match, causes that chain to be closed.  We can't deal
-	         with overlaps yet.
-	     (2) Any read outside an operand causes any chain it overlaps
-	         with to be closed, since we can't replace it.
-	     (3) Any read inside an operand is added if there's already
-	         an open chain for it.
-	     (4) For any REG_DEAD note we find, close open chains that
-	         overlap it.
-	     (5) For any write we find, close open chains that overlap it.
-	     (6) For any write we find in an operand, make a new chain.
-	     (7) For any REG_UNUSED, close any chains we just opened.  */
-
-	  icode = recog_memoized (insn);
-	  extract_insn (insn);
-	  if (! constrain_operands (1))
-	    fatal_insn_not_found (insn);
-	  preprocess_constraints ();
-	  alt = which_alternative;
-	  n_ops = recog_data.n_operands;
-
-	  /* Simplify the code below by rewriting things to reflect
-	     matching constraints.  Also promote OP_OUT to OP_INOUT
-	     in predicated instructions.  */
-
-	  predicated = GET_CODE (PATTERN (insn)) == COND_EXEC;
-	  for (i = 0; i < n_ops; ++i)
-	    {
-	      int matches = recog_op_alt[i][alt].matches;
-	      if (matches >= 0)
-		recog_op_alt[i][alt].cl = recog_op_alt[matches][alt].cl;
-	      if (matches >= 0 || recog_op_alt[i][alt].matched >= 0
-	          || (predicated && recog_data.operand_type[i] == OP_OUT))
-		recog_data.operand_type[i] = OP_INOUT;
-	    }
-
-	  /* Step 1: Close chains for which we have overlapping reads.  */
-	  for (i = 0; i < n_ops; i++)
-	    scan_rtx (insn, recog_data.operand_loc[i],
-		      NO_REGS, terminate_overlapping_read,
-		      recog_data.operand_type[i], 0);
-
-	  /* Step 2: Close chains for which we have reads outside operands.
-	     We do this by munging all operands into CC0, and closing
-	     everything remaining.  */
-
-	  for (i = 0; i < n_ops; i++)
-	    {
-	      old_operands[i] = recog_data.operand[i];
-	      /* Don't squash match_operator or match_parallel here, since
-		 we don't know that all of the contained registers are
-		 reachable by proper operands.  */
-	      if (recog_data.constraints[i][0] == '\0')
-		continue;
-	      *recog_data.operand_loc[i] = cc0_rtx;
-	    }
-	  for (i = 0; i < recog_data.n_dups; i++)
-	    {
-	      old_dups[i] = *recog_data.dup_loc[i];
-	      *recog_data.dup_loc[i] = cc0_rtx;
-	    }
-
-	  scan_rtx (insn, &PATTERN (insn), NO_REGS, terminate_all_read,
-		    OP_IN, 0);
-
-	  for (i = 0; i < recog_data.n_dups; i++)
-	    *recog_data.dup_loc[i] = old_dups[i];
-	  for (i = 0; i < n_ops; i++)
-	    *recog_data.operand_loc[i] = old_operands[i];
-	  if (recog_data.n_dups)
-	    df_insn_rescan (insn);
-
-	  /* Step 2B: Can't rename function call argument registers.  */
-	  if (CALL_P (insn) && CALL_INSN_FUNCTION_USAGE (insn))
-	    scan_rtx (insn, &CALL_INSN_FUNCTION_USAGE (insn),
-		      NO_REGS, terminate_all_read, OP_IN, 0);
-
-	  /* Step 2C: Can't rename asm operands that were originally
-	     hard registers.  */
-	  if (asm_noperands (PATTERN (insn)) > 0)
-	    for (i = 0; i < n_ops; i++)
-	      {
-		rtx *loc = recog_data.operand_loc[i];
-		rtx op = *loc;
-
-		if (REG_P (op)
-		    && REGNO (op) == ORIGINAL_REGNO (op)
-		    && (recog_data.operand_type[i] == OP_IN
-			|| recog_data.operand_type[i] == OP_INOUT))
-		  scan_rtx (insn, loc, NO_REGS, terminate_all_read, OP_IN, 0);
-	      }
-
-	  /* Step 3: Append to chains for reads inside operands.  */
-	  for (i = 0; i < n_ops + recog_data.n_dups; i++)
-	    {
-	      int opn = i < n_ops ? i : recog_data.dup_num[i - n_ops];
-	      rtx *loc = (i < n_ops
-			  ? recog_data.operand_loc[opn]
-			  : recog_data.dup_loc[i - n_ops]);
-	      enum reg_class cl = recog_op_alt[opn][alt].cl;
-	      enum op_type type = recog_data.operand_type[opn];
-
-	      /* Don't scan match_operand here, since we've no reg class
-		 information to pass down.  Any operands that we could
-		 substitute in will be represented elsewhere.  */
-	      if (recog_data.constraints[opn][0] == '\0')
-		continue;
-
-	      if (recog_op_alt[opn][alt].is_address)
-		scan_rtx_address (insn, loc, cl, mark_read, VOIDmode);
-	      else
-		scan_rtx (insn, loc, cl, mark_read, type, 0);
-	    }
-
-	  /* Step 3B: Record updates for regs in REG_INC notes, and
-	     source regs in REG_FRAME_RELATED_EXPR notes.  */
-	  for (note = REG_NOTES (insn); note; note = XEXP (note, 1))
-	    if (REG_NOTE_KIND (note) == REG_INC
-		|| REG_NOTE_KIND (note) == REG_FRAME_RELATED_EXPR)
-	      scan_rtx (insn, &XEXP (note, 0), ALL_REGS, mark_read,
-			OP_INOUT, 0);
-
-	  /* Step 4: Close chains for registers that die here.  */
-	  for (note = REG_NOTES (insn); note; note = XEXP (note, 1))
-	    if (REG_NOTE_KIND (note) == REG_DEAD)
-	      scan_rtx (insn, &XEXP (note, 0), NO_REGS, terminate_dead,
-			OP_IN, 0);
-
-	  /* Step 4B: If this is a call, any chain live at this point
-	     requires a caller-saved reg.  */
-	  if (CALL_P (insn))
-	    {
-	      struct du_chain *p;
-	      for (p = open_chains; p; p = p->next_chain)
-		p->need_caller_save_reg = 1;
-	    }
-
-	  /* Step 5: Close open chains that overlap writes.  Similar to
-	     step 2, we hide in-out operands, since we do not want to
-	     close these chains.  */
-
-	  for (i = 0; i < n_ops; i++)
-	    {
-	      old_operands[i] = recog_data.operand[i];
-	      if (recog_data.operand_type[i] == OP_INOUT)
-		*recog_data.operand_loc[i] = cc0_rtx;
-	    }
-	  for (i = 0; i < recog_data.n_dups; i++)
-	    {
-	      int opn = recog_data.dup_num[i];
-	      old_dups[i] = *recog_data.dup_loc[i];
-	      if (recog_data.operand_type[opn] == OP_INOUT)
-		*recog_data.dup_loc[i] = cc0_rtx;
-	    }
-
-	  scan_rtx (insn, &PATTERN (insn), NO_REGS, terminate_write, OP_IN, 0);
-
-	  for (i = 0; i < recog_data.n_dups; i++)
-	    *recog_data.dup_loc[i] = old_dups[i];
-	  for (i = 0; i < n_ops; i++)
-	    *recog_data.operand_loc[i] = old_operands[i];
-
-	  /* Step 6: Begin new chains for writes inside operands.  */
-	  /* ??? Many targets have output constraints on the SET_DEST
-	     of a call insn, which is stupid, since these are certainly
-	     ABI defined hard registers.  Don't change calls at all.
-	     Similarly take special care for asm statement that originally
-	     referenced hard registers.  */
-	  if (asm_noperands (PATTERN (insn)) > 0)
-	    {
-	      for (i = 0; i < n_ops; i++)
-		if (recog_data.operand_type[i] == OP_OUT)
-		  {
-		    rtx *loc = recog_data.operand_loc[i];
-		    rtx op = *loc;
-		    enum reg_class cl = recog_op_alt[i][alt].cl;
-
-		    if (REG_P (op)
-			&& REGNO (op) == ORIGINAL_REGNO (op))
-		      continue;
-
-		    scan_rtx (insn, loc, cl, mark_write, OP_OUT,
-			      recog_op_alt[i][alt].earlyclobber);
-		  }
-	    }
-	  else if (!CALL_P (insn))
-	    for (i = 0; i < n_ops + recog_data.n_dups; i++)
-	      {
-		int opn = i < n_ops ? i : recog_data.dup_num[i - n_ops];
-		rtx *loc = (i < n_ops
-			    ? recog_data.operand_loc[opn]
-			    : recog_data.dup_loc[i - n_ops]);
-		enum reg_class cl = recog_op_alt[opn][alt].cl;
-
-		if (recog_data.operand_type[opn] == OP_OUT)
-		  scan_rtx (insn, loc, cl, mark_write, OP_OUT,
-			    recog_op_alt[opn][alt].earlyclobber);
-	      }
-
-	  /* Step 6B: Record destination regs in REG_FRAME_RELATED_EXPR
-	     notes for update.  */
-	  for (note = REG_NOTES (insn); note; note = XEXP (note, 1))
-	    if (REG_NOTE_KIND (note) == REG_FRAME_RELATED_EXPR)
-	      scan_rtx (insn, &XEXP (note, 0), ALL_REGS, mark_access,
-			OP_INOUT, 0);
-
-	  /* Step 7: Close chains for registers that were never
-	     really used here.  */
-	  for (note = REG_NOTES (insn); note; note = XEXP (note, 1))
-	    if (REG_NOTE_KIND (note) == REG_UNUSED)
-	      scan_rtx (insn, &XEXP (note, 0), NO_REGS, terminate_dead,
-			OP_IN, 0);
-	}
-      if (insn == BB_END (bb))
-	break;
-    }
-
-  /* Since we close every chain when we find a REG_DEAD note, anything that
-     is still open lives past the basic block, so it can't be renamed.  */
-  return closed_chains;
-}
-
-/* Dump all def/use chains in CHAINS to DUMP_FILE.  They are
-   printed in reverse order as that's how we build them.  */
-
-static void
-dump_def_use_chain (struct du_chain *chains)
-{
-  while (chains)
-    {
-      struct du_chain *this_du = chains;
-      int r = REGNO (*this_du->loc);
-      int nregs = hard_regno_nregs[r][GET_MODE (*this_du->loc)];
-      fprintf (dump_file, "Register %s (%d):", reg_names[r], nregs);
-      while (this_du)
-	{
-	  fprintf (dump_file, " %d [%s]", INSN_UID (this_du->insn),
-		   reg_class_names[this_du->cl]);
-	  this_du = this_du->next_use;
-	}
-      fprintf (dump_file, "\n");
-      chains = chains->next_chain;
-    }
-}
-
 /* The following code does forward propagation of hard register copies.
    The object is to eliminate as many dependencies as possible, so that
    we have the most scheduling freedom.  As a side effect, we also clean
@@ -1799,7 +839,7 @@ copyprop_hardreg_forward_1 (basic_block 
 
 /* Main entry point for the forward copy propagation optimization.  */
 
-static void
+static unsigned int
 copyprop_hardreg_forward (void)
 {
   struct value_data *all_vd;
@@ -1831,6 +871,7 @@ copyprop_hardreg_forward (void)
 
   sbitmap_free (visited);  
   free (all_vd);
+  return 0;
 }
 
 /* Dump the value chain data to stderr.  */
@@ -1938,66 +979,23 @@ validate_value_data (struct value_data *
 #endif
 
 static bool
-gate_handle_regrename (void)
-{
-  return (optimize > 0 && (flag_rename_registers));
-}
-
-
-/* Run the regrename and cprop passes.  */
-static unsigned int
-rest_of_handle_regrename (void)
-{
-  regrename_optimize ();
-  return 0;
-}
-
-struct rtl_opt_pass pass_regrename =
-{
- {
-  RTL_PASS,
-  "rnreg",                              /* name */
-  gate_handle_regrename,                /* gate */
-  rest_of_handle_regrename,             /* execute */
-  NULL,                                 /* sub */
-  NULL,                                 /* next */
-  0,                                    /* static_pass_number */
-  TV_RENAME_REGISTERS,                  /* tv_id */
-  0,                                    /* properties_required */
-  0,                                    /* properties_provided */
-  0,                                    /* properties_destroyed */
-  0,                                    /* todo_flags_start */
-  TODO_df_finish | TODO_verify_rtl_sharing |
-  TODO_dump_func                        /* todo_flags_finish */
- }
-};
-
-static bool
 gate_handle_cprop (void)
 {
   return (optimize > 0 && (flag_cprop_registers));
 }
 
 
-/* Run the regrename and cprop passes.  */
-static unsigned int
-rest_of_handle_cprop (void)
-{
-  copyprop_hardreg_forward ();
-  return 0;
-}
-
 struct rtl_opt_pass pass_cprop_hardreg =
 {
  {
   RTL_PASS,
   "cprop_hardreg",                      /* name */
   gate_handle_cprop,                    /* gate */
-  rest_of_handle_cprop,                 /* execute */
+  copyprop_hardreg_forward,             /* execute */
   NULL,                                 /* sub */
   NULL,                                 /* next */
   0,                                    /* static_pass_number */
-  TV_RENAME_REGISTERS,                  /* tv_id */
+  TV_CPROP_REGISTERS,                   /* tv_id */
   0,                                    /* properties_required */
   0,                                    /* properties_provided */
   0,                                    /* properties_destroyed */

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