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Re: Split postreload gcse from gcse.c


And of course, I attached the wrong patch.  The larger the patch,
the more likely it is you attach the wrong one.
So again,

On Wednesday 18 August 2004 18:08, Steven Bosscher wrote:
> Hi,
>
> This patch splits postreload gcse from gcse.c to a new file
> called (surprise) postreload-gcse.c.
>
> To avoid having yet another pair of hash/equivalence functions,
> I've merged expr_hash and expr_equiv from gcse.c with canon_hash
> and exp_equiv from cse.c
>
> I've bootstrapped it on a number of targets, as have others, and
> we've also looked at performance.  This patch makes postreload
> gcse a lot faster, but the generated code is not better overall,
> unfortunately.
>
> For example, on x86 most test cases improve slightly, but eon
> takes a 7% hit.  On PowerPC, for which this pass was originally
> contributed, there's also little or no overall improvement due to
> postreload gcse, neither for compile time nor for the generated
> code.
>
> So what's left with this patch is:
> - splitting it off from gcse.c, which is a nice cleanup, and
> - merging a bunch of almost-duplicate functions.
>
> I've just finished bootstrapping the patch (needed re-doing after
> rth's RTX_UNCHANGING_P patch) and testing is in progress.
> OK if it passes?
>
> Gr.
> Steven
>
>
>
>
>         * Makefile.in (OBJS-common): Add postreload-gcse.c.
>         Add new postreload-gcse.o.
>         * cse.c (SAFE_HASH): Define as wrapper around safe_hash.
>         (lookup_as_function, insert, rehash_using_reg, use_related_value,
>         equiv_constant): Use SAFE_HASH instead of safe_hash.
>         (exp_equiv_p): Export.  Add for_gcse argument when comparing
>         for GCSE.
>         (lookup, lookup_for_remove, merge_equiv_classes, find_best_addr,
>         find_comparison_args, fold_rtx, cse_insn): Update callers.
>         (hash_rtx): New function derived from old canon_hash and bits
>         from gcse.c hash_expr_1.
>         (canon_hash_string): Rename to hash_rtx_string.
>         (canon_hash, safe_hash): Make static inline.  Call hash_rtx.
>         * cselib.c (hash_rtx): Rename to cselib_hash_rtx.
>         (cselib_lookup): Update this caller.
>         * gcse.c (modify_mem_list_set, canon_modify_mem_list_set):
>         Make static.
>         (hash_expr): Call hash_rtx.
>         (ldst_entry): Likewise.
>         (expr_equiv_p): Call exp_equiv_p.
>         (struct unoccr, hash_expr_1, hash_string_1, lookup_expr,
>         reg_used_on_edge, reg_set_between_after_reload_p,
>         reg_used_between_after_reload_p, get_avail_load_store_reg,
>         is_jump_table_basic_block, bb_has_well_behaved_predecessors,
>         get_bb_avail_insn, hash_scan_set_after_reload,
>         compute_hash_table_after_reload,
>         eliminate_partially_redundant_loads, gcse_after_reload,
>         get_bb_avail_insn, gcse_after_reload_main): Remove.
>         * postreload-gcse.c: New file, reincarnating most of the above.
>         * rtl.h (exp_equiv_p, hash_rtx): New prototypes.
>         (gcse_after_reload_main): Update prototype.
>         * timevar.def (TV_GCSE_AFTER_RELOAD): New timevar.
>         * passes.c (rest_of_handle_gcse2): Use it.


Gr.
Steven
Index: Makefile.in
===================================================================
RCS file: /cvs/gcc/gcc/gcc/Makefile.in,v
retrieving revision 1.1349
diff -c -3 -p -r1.1349 Makefile.in
*** Makefile.in	17 Aug 2004 16:17:04 -0000	1.1349
--- Makefile.in	18 Aug 2004 17:51:29 -0000
*************** OBJS-common = \
*** 899,913 ****
   genrtl.o ggc-common.o global.o graph.o gtype-desc.o			   \
   haifa-sched.o hooks.o ifcvt.o insn-attrtab.o insn-emit.o insn-modes.o	   \
   insn-extract.o insn-opinit.o insn-output.o insn-peep.o insn-recog.o	   \
!  insn-preds.o integrate.o intl.o jump.o  langhooks.o lcm.o lists.o 	   \
!  local-alloc.o loop.o modulo-sched.o					   \
!  optabs.o options.o opts.o params.o postreload.o predict.o		   \
   print-rtl.o print-tree.o value-prof.o var-tracking.o			   \
   profile.o ra.o ra-build.o ra-colorize.o ra-debug.o ra-rewrite.o	   \
   real.o recog.o reg-stack.o regclass.o regmove.o regrename.o		   \
   reload.o reload1.o reorg.o resource.o rtl.o rtlanal.o rtl-error.o	   \
   sbitmap.o sched-deps.o sched-ebb.o sched-rgn.o sched-vis.o sdbout.o	   \
!  simplify-rtx.o sreal.o stmt.o stor-layout.o stringpool.o 	 	  \
   targhooks.o timevar.o toplev.o tracer.o tree.o tree-dump.o unroll.o	   \
   varasm.o varray.o vec.o version.o vmsdbgout.o xcoffout.o alloc-pool.o	   \
   et-forest.o cfghooks.o bt-load.o pretty-print.o $(GGC) web.o passes.o	   \
--- 899,916 ----
   genrtl.o ggc-common.o global.o graph.o gtype-desc.o			   \
   haifa-sched.o hooks.o ifcvt.o insn-attrtab.o insn-emit.o insn-modes.o	   \
   insn-extract.o insn-opinit.o insn-output.o insn-peep.o insn-recog.o	   \
!  integrate.o intl.o jump.o  langhooks.o lcm.o lists.o local-alloc.o  	   \
!  loop.o modulo-sched.o optabs.o options.o opts.o			   \
!  params.o postreload.o postreload-gcse.o predict.o			   \
!  insn-preds.o integrate.o intl.o jump.o langhooks.o lcm.o lists.o 	   \
!  local-alloc.o loop.o modulo-sched.o optabs.o options.o opts.o		   \
!  params.o postreload.o postreload-gcse.o predict.o			   \
   print-rtl.o print-tree.o value-prof.o var-tracking.o			   \
   profile.o ra.o ra-build.o ra-colorize.o ra-debug.o ra-rewrite.o	   \
   real.o recog.o reg-stack.o regclass.o regmove.o regrename.o		   \
   reload.o reload1.o reorg.o resource.o rtl.o rtlanal.o rtl-error.o	   \
   sbitmap.o sched-deps.o sched-ebb.o sched-rgn.o sched-vis.o sdbout.o	   \
!  simplify-rtx.o sreal.o stmt.o stor-layout.o stringpool.o		   \
   targhooks.o timevar.o toplev.o tracer.o tree.o tree-dump.o unroll.o	   \
   varasm.o varray.o vec.o version.o vmsdbgout.o xcoffout.o alloc-pool.o	   \
   et-forest.o cfghooks.o bt-load.o pretty-print.o $(GGC) web.o passes.o	   \
*************** postreload.o : postreload.c $(CONFIG_H) 
*** 2047,2052 ****
--- 2050,2059 ----
     $(EXPR_H) $(OPTABS_H) reload.h $(REGS_H) hard-reg-set.h insn-config.h \
     $(BASIC_BLOCK_H) $(RECOG_H) output.h function.h toplev.h cselib.h $(TM_P_H) \
     except.h $(TREE_H)
+ postreload-gcse.o : postreload-gcse.c $(CONFIG_H) $(SYSTEM_H) coretypes.h $(TM_H) \
+    $(RTL_H) $(REGS_H) hard-reg-set.h $(FLAGS_H) real.h insn-config.h $(GGC_H) \
+    $(RECOG_H) $(EXPR_H) $(BASIC_BLOCK_H) function.h output.h toplev.h $(TM_P_H) \
+    except.h $(TREE_H)
  caller-save.o : caller-save.c $(CONFIG_H) $(SYSTEM_H) coretypes.h $(TM_H) $(RTL_H) \
     $(FLAGS_H) $(REGS_H) hard-reg-set.h insn-config.h $(BASIC_BLOCK_H) function.h \
     $(RECOG_H) reload.h $(EXPR_H) toplev.h $(TM_P_H)
Index: cse.c
===================================================================
RCS file: /cvs/gcc/gcc/gcc/cse.c,v
retrieving revision 1.308
diff -c -3 -p -r1.308 cse.c
*** cse.c	18 Aug 2004 08:23:37 -0000	1.308
--- cse.c	18 Aug 2004 17:51:30 -0000
*************** struct table_elt
*** 489,494 ****
--- 489,500 ----
    ? (((unsigned) REG << 7) + (unsigned) REG_QTY (REGNO (X)))	\
    : canon_hash (X, M)) & HASH_MASK)
  
+ /* Like HASH, but without side-effects.  */
+ #define SAFE_HASH(X, M)	\
+  ((REG_P (X) && REGNO (X) >= FIRST_PSEUDO_REGISTER	\
+   ? (((unsigned) REG << 7) + (unsigned) REG_QTY (REGNO (X)))	\
+   : safe_hash (X, M)) & HASH_MASK)
+ 
  /* Determine whether register number N is considered a fixed register for the
     purpose of approximating register costs.
     It is desirable to replace other regs with fixed regs, to reduce need for
*************** static void rehash_using_reg (rtx);
*** 625,634 ****
  static void invalidate_memory (void);
  static void invalidate_for_call (void);
  static rtx use_related_value (rtx, struct table_elt *);
! static unsigned canon_hash (rtx, enum machine_mode);
! static unsigned canon_hash_string (const char *);
! static unsigned safe_hash (rtx, enum machine_mode);
! static int exp_equiv_p (rtx, rtx, int, int);
  static rtx canon_reg (rtx, rtx);
  static void find_best_addr (rtx, rtx *, enum machine_mode);
  static enum rtx_code find_comparison_args (enum rtx_code, rtx *, rtx *,
--- 631,641 ----
  static void invalidate_memory (void);
  static void invalidate_for_call (void);
  static rtx use_related_value (rtx, struct table_elt *);
! 
! static inline unsigned canon_hash (rtx, enum machine_mode);
! static inline unsigned safe_hash (rtx, enum machine_mode);
! static unsigned hash_rtx_string (const char *);
! 
  static rtx canon_reg (rtx, rtx);
  static void find_best_addr (rtx, rtx *, enum machine_mode);
  static enum rtx_code find_comparison_args (enum rtx_code, rtx *, rtx *,
*************** lookup (rtx x, unsigned int hash, enum m
*** 1324,1330 ****
  
    for (p = table[hash]; p; p = p->next_same_hash)
      if (mode == p->mode && ((x == p->exp && REG_P (x))
! 			    || exp_equiv_p (x, p->exp, !REG_P (x), 0)))
        return p;
  
    return 0;
--- 1331,1337 ----
  
    for (p = table[hash]; p; p = p->next_same_hash)
      if (mode == p->mode && ((x == p->exp && REG_P (x))
! 			    || exp_equiv_p (x, p->exp, !REG_P (x), false)))
        return p;
  
    return 0;
*************** lookup_for_remove (rtx x, unsigned int h
*** 1352,1358 ****
    else
      {
        for (p = table[hash]; p; p = p->next_same_hash)
! 	if (mode == p->mode && (x == p->exp || exp_equiv_p (x, p->exp, 0, 0)))
  	  return p;
      }
  
--- 1359,1366 ----
    else
      {
        for (p = table[hash]; p; p = p->next_same_hash)
! 	if (mode == p->mode
! 	    && (x == p->exp || exp_equiv_p (x, p->exp, 0, false)))
  	  return p;
      }
  
*************** static rtx
*** 1366,1372 ****
  lookup_as_function (rtx x, enum rtx_code code)
  {
    struct table_elt *p
!     = lookup (x, safe_hash (x, VOIDmode) & HASH_MASK, GET_MODE (x));
  
    /* If we are looking for a CONST_INT, the mode doesn't really matter, as
       long as we are narrowing.  So if we looked in vain for a mode narrower
--- 1374,1380 ----
  lookup_as_function (rtx x, enum rtx_code code)
  {
    struct table_elt *p
!     = lookup (x, SAFE_HASH (x, VOIDmode), GET_MODE (x));
  
    /* If we are looking for a CONST_INT, the mode doesn't really matter, as
       long as we are narrowing.  So if we looked in vain for a mode narrower
*************** lookup_as_function (rtx x, enum rtx_code
*** 1376,1382 ****
      {
        x = copy_rtx (x);
        PUT_MODE (x, word_mode);
!       p = lookup (x, safe_hash (x, VOIDmode) & HASH_MASK, word_mode);
      }
  
    if (p == 0)
--- 1384,1390 ----
      {
        x = copy_rtx (x);
        PUT_MODE (x, word_mode);
!       p = lookup (x, SAFE_HASH (x, VOIDmode), word_mode);
      }
  
    if (p == 0)
*************** lookup_as_function (rtx x, enum rtx_code
*** 1385,1391 ****
    for (p = p->first_same_value; p; p = p->next_same_value)
      if (GET_CODE (p->exp) == code
  	/* Make sure this is a valid entry in the table.  */
! 	&& exp_equiv_p (p->exp, p->exp, 1, 0))
        return p->exp;
  
    return 0;
--- 1393,1399 ----
    for (p = p->first_same_value; p; p = p->next_same_value)
      if (GET_CODE (p->exp) == code
  	/* Make sure this is a valid entry in the table.  */
! 	&& exp_equiv_p (p->exp, p->exp, 1, false))
        return p->exp;
  
    return 0;
*************** insert (rtx x, struct table_elt *classp,
*** 1568,1574 ****
        if (subexp != 0)
  	{
  	  /* Get the integer-free subexpression in the hash table.  */
! 	  subhash = safe_hash (subexp, mode) & HASH_MASK;
  	  subelt = lookup (subexp, subhash, mode);
  	  if (subelt == 0)
  	    subelt = insert (subexp, NULL, subhash, mode);
--- 1576,1582 ----
        if (subexp != 0)
  	{
  	  /* Get the integer-free subexpression in the hash table.  */
! 	  subhash = SAFE_HASH (subexp, mode);
  	  subelt = lookup (subexp, subhash, mode);
  	  if (subelt == 0)
  	    subelt = insert (subexp, NULL, subhash, mode);
*************** merge_equiv_classes (struct table_elt *c
*** 1622,1628 ****
        /* Remove old entry, make a new one in CLASS1's class.
  	 Don't do this for invalid entries as we cannot find their
  	 hash code (it also isn't necessary).  */
!       if (REG_P (exp) || exp_equiv_p (exp, exp, 1, 0))
  	{
  	  bool need_rehash = false;
  
--- 1630,1636 ----
        /* Remove old entry, make a new one in CLASS1's class.
  	 Don't do this for invalid entries as we cannot find their
  	 hash code (it also isn't necessary).  */
!       if (REG_P (exp) || exp_equiv_p (exp, exp, 1, false))
  	{
  	  bool need_rehash = false;
  
*************** rehash_using_reg (rtx x)
*** 1917,1924 ****
        {
  	next = p->next_same_hash;
  	if (reg_mentioned_p (x, p->exp)
! 	    && exp_equiv_p (p->exp, p->exp, 1, 0)
! 	    && i != (hash = safe_hash (p->exp, p->mode) & HASH_MASK))
  	  {
  	    if (p->next_same_hash)
  	      p->next_same_hash->prev_same_hash = p->prev_same_hash;
--- 1925,1932 ----
        {
  	next = p->next_same_hash;
  	if (reg_mentioned_p (x, p->exp)
! 	    && exp_equiv_p (p->exp, p->exp, 1, false)
! 	    && i != (hash = SAFE_HASH (p->exp, p->mode)))
  	  {
  	    if (p->next_same_hash)
  	      p->next_same_hash->prev_same_hash = p->prev_same_hash;
*************** use_related_value (rtx x, struct table_e
*** 2017,2023 ****
        rtx subexp = get_related_value (x);
        if (subexp != 0)
  	relt = lookup (subexp,
! 		       safe_hash (subexp, GET_MODE (subexp)) & HASH_MASK,
  		       GET_MODE (subexp));
      }
  
--- 2025,2031 ----
        rtx subexp = get_related_value (x);
        if (subexp != 0)
  	relt = lookup (subexp,
! 		       SAFE_HASH (subexp, GET_MODE (subexp)),
  		       GET_MODE (subexp));
      }
  
*************** use_related_value (rtx x, struct table_e
*** 2068,2074 ****
  
  /* Hash a string.  Just add its bytes up.  */
  static inline unsigned
! canon_hash_string (const char *ps)
  {
    unsigned hash = 0;
    const unsigned char *p = (const unsigned char *) ps;
--- 2076,2082 ----
  
  /* Hash a string.  Just add its bytes up.  */
  static inline unsigned
! hash_rtx_string (const char *ps)
  {
    unsigned hash = 0;
    const unsigned char *p = (const unsigned char *) ps;
*************** canon_hash_string (const char *ps)
*** 2085,2107 ****
     MODE is used in hashing for CONST_INTs only;
     otherwise the mode of X is used.
  
!    Store 1 in do_not_record if any subexpression is volatile.
  
!    Store 1 in hash_arg_in_memory if X contains a MEM rtx
!    which does not have the MEM_READONLY_P bit set.
  
     Note that cse_insn knows that the hash code of a MEM expression
     is just (int) MEM plus the hash code of the address.  */
  
! static unsigned
! canon_hash (rtx x, enum machine_mode mode)
  {
    int i, j;
    unsigned hash = 0;
    enum rtx_code code;
    const char *fmt;
  
!   /* repeat is used to turn tail-recursion into iteration.  */
   repeat:
    if (x == 0)
      return hash;
--- 2093,2118 ----
     MODE is used in hashing for CONST_INTs only;
     otherwise the mode of X is used.
  
!    Store 1 in DO_NOT_RECORD_P if any subexpression is volatile.
  
!    If HASH_ARG_IN_MEMORY_P is not NULL, store 1 in it if X contains
!    a MEM rtx which does not have the RTX_UNCHANGING_P bit set.
  
     Note that cse_insn knows that the hash code of a MEM expression
     is just (int) MEM plus the hash code of the address.  */
  
! unsigned
! hash_rtx (rtx x, enum machine_mode mode, int *do_not_record_p,
! 	  int *hash_arg_in_memory_p, bool have_reg_qty)
  {
    int i, j;
    unsigned hash = 0;
    enum rtx_code code;
    const char *fmt;
  
!   /* Used to turn recursion into iteration.  We can't rely on GCC's
!      tail-recursion elimination since we need to keep accumulating values
!      in HASH.  */
   repeat:
    if (x == 0)
      return hash;
*************** canon_hash (rtx x, enum machine_mode mod
*** 2112,2159 ****
      case REG:
        {
  	unsigned int regno = REGNO (x);
- 	bool record;
- 
- 	/* On some machines, we can't record any non-fixed hard register,
- 	   because extending its life will cause reload problems.  We
- 	   consider ap, fp, sp, gp to be fixed for this purpose.
- 
- 	   We also consider CCmode registers to be fixed for this purpose;
- 	   failure to do so leads to failure to simplify 0<100 type of
- 	   conditionals.
- 
- 	   On all machines, we can't record any global registers.
- 	   Nor should we record any register that is in a small
- 	   class, as defined by CLASS_LIKELY_SPILLED_P.  */
  
! 	if (regno >= FIRST_PSEUDO_REGISTER)
! 	  record = true;
! 	else if (x == frame_pointer_rtx
! 		 || x == hard_frame_pointer_rtx
! 		 || x == arg_pointer_rtx
! 		 || x == stack_pointer_rtx
! 		 || x == pic_offset_table_rtx)
! 	  record = true;
! 	else if (global_regs[regno])
! 	  record = false;
! 	else if (fixed_regs[regno])
! 	  record = true;
! 	else if (GET_MODE_CLASS (GET_MODE (x)) == MODE_CC)
! 	  record = true;
! 	else if (SMALL_REGISTER_CLASSES)
! 	  record = false;
! 	else if (CLASS_LIKELY_SPILLED_P (REGNO_REG_CLASS (regno)))
! 	  record = false;
! 	else
! 	  record = true;
! 
! 	if (!record)
  	  {
! 	    do_not_record = 1;
! 	    return 0;
  	  }
  
! 	hash += ((unsigned) REG << 7) + (unsigned) REG_QTY (regno);
  	return hash;
        }
  
--- 2123,2174 ----
      case REG:
        {
  	unsigned int regno = REGNO (x);
  
! 	if (!reload_completed)
  	  {
! 	    /* On some machines, we can't record any non-fixed hard register,
! 	       because extending its life will cause reload problems.  We
! 	       consider ap, fp, sp, gp to be fixed for this purpose.
! 
! 	       We also consider CCmode registers to be fixed for this purpose;
! 	       failure to do so leads to failure to simplify 0<100 type of
! 	       conditionals.
! 
! 	       On all machines, we can't record any global registers.
! 	       Nor should we record any register that is in a small
! 	       class, as defined by CLASS_LIKELY_SPILLED_P.  */
! 	    bool record;
! 
! 	    if (regno >= FIRST_PSEUDO_REGISTER)
! 	      record = true;
! 	    else if (x == frame_pointer_rtx
! 		     || x == hard_frame_pointer_rtx
! 		     || x == arg_pointer_rtx
! 		     || x == stack_pointer_rtx
! 		     || x == pic_offset_table_rtx)
! 	      record = true;
! 	    else if (global_regs[regno])
! 	      record = false;
! 	    else if (fixed_regs[regno])
! 	      record = true;
! 	    else if (GET_MODE_CLASS (GET_MODE (x)) == MODE_CC)
! 	      record = true;
! 	    else if (SMALL_REGISTER_CLASSES)
! 	      record = false;
! 	    else if (CLASS_LIKELY_SPILLED_P (REGNO_REG_CLASS (regno)))
! 	      record = false;
! 	    else
! 	      record = true;
! 
! 	    if (!record)
! 	      {
! 		*do_not_record_p = 1;
! 		return 0;
! 	      }
  	  }
  
! 	hash += ((unsigned int) REG << 7);
!         hash += (have_reg_qty ? (unsigned) REG_QTY (regno) : regno);
  	return hash;
        }
  
*************** canon_hash (rtx x, enum machine_mode mod
*** 2164,2170 ****
        {
  	if (REG_P (SUBREG_REG (x)))
  	  {
! 	    hash += (((unsigned) SUBREG << 7)
  		     + REGNO (SUBREG_REG (x))
  		     + (SUBREG_BYTE (x) / UNITS_PER_WORD));
  	    return hash;
--- 2179,2185 ----
        {
  	if (REG_P (SUBREG_REG (x)))
  	  {
! 	    hash += (((unsigned int) SUBREG << 7)
  		     + REGNO (SUBREG_REG (x))
  		     + (SUBREG_BYTE (x) / UNITS_PER_WORD));
  	    return hash;
*************** canon_hash (rtx x, enum machine_mode mod
*** 2173,2193 ****
        }
  
      case CONST_INT:
!       {
! 	unsigned HOST_WIDE_INT tem = INTVAL (x);
! 	hash += ((unsigned) CONST_INT << 7) + (unsigned) mode + tem;
! 	return hash;
!       }
  
      case CONST_DOUBLE:
        /* This is like the general case, except that it only counts
  	 the integers representing the constant.  */
!       hash += (unsigned) code + (unsigned) GET_MODE (x);
        if (GET_MODE (x) != VOIDmode)
  	hash += real_hash (CONST_DOUBLE_REAL_VALUE (x));
        else
! 	hash += ((unsigned) CONST_DOUBLE_LOW (x)
! 		 + (unsigned) CONST_DOUBLE_HIGH (x));
        return hash;
  
      case CONST_VECTOR:
--- 2188,2206 ----
        }
  
      case CONST_INT:
!       hash += (((unsigned int) CONST_INT << 7) + (unsigned int) mode
!                + (unsigned int) INTVAL (x));
!       return hash;
  
      case CONST_DOUBLE:
        /* This is like the general case, except that it only counts
  	 the integers representing the constant.  */
!       hash += (unsigned int) code + (unsigned int) GET_MODE (x);
        if (GET_MODE (x) != VOIDmode)
  	hash += real_hash (CONST_DOUBLE_REAL_VALUE (x));
        else
! 	hash += ((unsigned int) CONST_DOUBLE_LOW (x)
! 		 + (unsigned int) CONST_DOUBLE_HIGH (x));
        return hash;
  
      case CONST_VECTOR:
*************** canon_hash (rtx x, enum machine_mode mod
*** 2200,2206 ****
  	for (i = 0; i < units; ++i)
  	  {
  	    elt = CONST_VECTOR_ELT (x, i);
! 	    hash += canon_hash (elt, GET_MODE (elt));
  	  }
  
  	return hash;
--- 2213,2220 ----
  	for (i = 0; i < units; ++i)
  	  {
  	    elt = CONST_VECTOR_ELT (x, i);
! 	    hash += hash_rtx (elt, GET_MODE (elt), do_not_record_p,
! 			      hash_arg_in_memory_p, have_reg_qty);
  	  }
  
  	return hash;
*************** canon_hash (rtx x, enum machine_mode mod
*** 2208,2230 ****
  
        /* Assume there is only one rtx object for any given label.  */
      case LABEL_REF:
!       hash += ((unsigned) LABEL_REF << 7) + (unsigned long) XEXP (x, 0);
        return hash;
  
      case SYMBOL_REF:
!       hash += ((unsigned) SYMBOL_REF << 7) + (unsigned long) XSTR (x, 0);
!       return hash;
  
      case MEM:
        /* We don't record if marked volatile or if BLKmode since we don't
  	 know the size of the move.  */
        if (MEM_VOLATILE_P (x) || GET_MODE (x) == BLKmode)
  	{
! 	  do_not_record = 1;
  	  return 0;
  	}
!       if (!MEM_READONLY_P (x))
! 	hash_arg_in_memory = 1;
  
        /* Now that we have already found this special case,
  	 might as well speed it up as much as possible.  */
--- 2222,2260 ----
  
        /* Assume there is only one rtx object for any given label.  */
      case LABEL_REF:
!       /* We don't hash on the address of the CODE_LABEL to avoid bootstrap
! 	 differences and differences between each stage's debugging dumps.  */
! 	 hash += (((unsigned int) LABEL_REF << 7)
! 		  + CODE_LABEL_NUMBER (XEXP (x, 0)));
        return hash;
  
      case SYMBOL_REF:
!       {
! 	/* Don't hash on the symbol's address to avoid bootstrap differences.
! 	   Different hash values may cause expressions to be recorded in
! 	   different orders and thus different registers to be used in the
! 	   final assembler.  This also avoids differences in the dump files
! 	   between various stages.  */
! 	unsigned int h = 0;
! 	const unsigned char *p = (const unsigned char *) XSTR (x, 0);
! 
! 	while (*p)
! 	  h += (h << 7) + *p++; /* ??? revisit */
! 
! 	hash += ((unsigned int) SYMBOL_REF << 7) + h;
! 	return hash;
!       }
  
      case MEM:
        /* We don't record if marked volatile or if BLKmode since we don't
  	 know the size of the move.  */
        if (MEM_VOLATILE_P (x) || GET_MODE (x) == BLKmode)
  	{
! 	  *do_not_record_p = 1;
  	  return 0;
  	}
!       if (hash_arg_in_memory_p && !MEM_READONLY_P (x))
! 	*hash_arg_in_memory_p = 1;
  
        /* Now that we have already found this special case,
  	 might as well speed it up as much as possible.  */
*************** canon_hash (rtx x, enum machine_mode mod
*** 2236,2250 ****
        /* A USE that mentions non-volatile memory needs special
  	 handling since the MEM may be BLKmode which normally
  	 prevents an entry from being made.  Pure calls are
! 	 marked by a USE which mentions BLKmode memory.  */
        if (MEM_P (XEXP (x, 0))
  	  && ! MEM_VOLATILE_P (XEXP (x, 0)))
  	{
  	  hash += (unsigned) USE;
  	  x = XEXP (x, 0);
  
! 	  if (!MEM_READONLY_P (x))
! 	    hash_arg_in_memory = 1;
  
  	  /* Now that we have already found this special case,
  	     might as well speed it up as much as possible.  */
--- 2266,2281 ----
        /* A USE that mentions non-volatile memory needs special
  	 handling since the MEM may be BLKmode which normally
  	 prevents an entry from being made.  Pure calls are
! 	 marked by a USE which mentions BLKmode memory.
! 	 See calls.c:emit_call_1.  */
        if (MEM_P (XEXP (x, 0))
  	  && ! MEM_VOLATILE_P (XEXP (x, 0)))
  	{
  	  hash += (unsigned) USE;
  	  x = XEXP (x, 0);
  
! 	  if (hash_arg_in_memory_p && !MEM_READONLY_P (x))
! 	    *hash_arg_in_memory_p = 1;
  
  	  /* Now that we have already found this special case,
  	     might as well speed it up as much as possible.  */
*************** canon_hash (rtx x, enum machine_mode mod
*** 2264,2297 ****
      case CC0:
      case CALL:
      case UNSPEC_VOLATILE:
!       do_not_record = 1;
        return 0;
  
      case ASM_OPERANDS:
        if (MEM_VOLATILE_P (x))
  	{
! 	  do_not_record = 1;
  	  return 0;
  	}
        else
  	{
  	  /* We don't want to take the filename and line into account.  */
  	  hash += (unsigned) code + (unsigned) GET_MODE (x)
! 	    + canon_hash_string (ASM_OPERANDS_TEMPLATE (x))
! 	    + canon_hash_string (ASM_OPERANDS_OUTPUT_CONSTRAINT (x))
  	    + (unsigned) ASM_OPERANDS_OUTPUT_IDX (x);
  
  	  if (ASM_OPERANDS_INPUT_LENGTH (x))
  	    {
  	      for (i = 1; i < ASM_OPERANDS_INPUT_LENGTH (x); i++)
  		{
! 		  hash += (canon_hash (ASM_OPERANDS_INPUT (x, i),
! 				       GET_MODE (ASM_OPERANDS_INPUT (x, i)))
! 			   + canon_hash_string (ASM_OPERANDS_INPUT_CONSTRAINT
! 						(x, i)));
  		}
  
! 	      hash += canon_hash_string (ASM_OPERANDS_INPUT_CONSTRAINT (x, 0));
  	      x = ASM_OPERANDS_INPUT (x, 0);
  	      mode = GET_MODE (x);
  	      goto repeat;
--- 2295,2330 ----
      case CC0:
      case CALL:
      case UNSPEC_VOLATILE:
!       *do_not_record_p = 1;
        return 0;
  
      case ASM_OPERANDS:
        if (MEM_VOLATILE_P (x))
  	{
! 	  *do_not_record_p = 1;
  	  return 0;
  	}
        else
  	{
  	  /* We don't want to take the filename and line into account.  */
  	  hash += (unsigned) code + (unsigned) GET_MODE (x)
! 	    + hash_rtx_string (ASM_OPERANDS_TEMPLATE (x))
! 	    + hash_rtx_string (ASM_OPERANDS_OUTPUT_CONSTRAINT (x))
  	    + (unsigned) ASM_OPERANDS_OUTPUT_IDX (x);
  
  	  if (ASM_OPERANDS_INPUT_LENGTH (x))
  	    {
  	      for (i = 1; i < ASM_OPERANDS_INPUT_LENGTH (x); i++)
  		{
! 		  hash += (hash_rtx (ASM_OPERANDS_INPUT (x, i),
! 				     GET_MODE (ASM_OPERANDS_INPUT (x, i)),
! 				     do_not_record_p, hash_arg_in_memory_p,
! 				     have_reg_qty)
! 			   + hash_rtx_string
! 				(ASM_OPERANDS_INPUT_CONSTRAINT (x, i)));
  		}
  
! 	      hash += hash_rtx_string (ASM_OPERANDS_INPUT_CONSTRAINT (x, 0));
  	      x = ASM_OPERANDS_INPUT (x, 0);
  	      mode = GET_MODE (x);
  	      goto repeat;
*************** canon_hash (rtx x, enum machine_mode mod
*** 2312,2359 ****
      {
        if (fmt[i] == 'e')
  	{
- 	  rtx tem = XEXP (x, i);
- 
  	  /* If we are about to do the last recursive call
  	     needed at this level, change it into iteration.
  	     This function  is called enough to be worth it.  */
  	  if (i == 0)
  	    {
! 	      x = tem;
  	      goto repeat;
  	    }
! 	  hash += canon_hash (tem, 0);
  	}
        else if (fmt[i] == 'E')
  	for (j = 0; j < XVECLEN (x, i); j++)
! 	  hash += canon_hash (XVECEXP (x, i, j), 0);
        else if (fmt[i] == 's')
! 	hash += canon_hash_string (XSTR (x, i));
        else if (fmt[i] == 'i')
! 	{
! 	  unsigned tem = XINT (x, i);
! 	  hash += tem;
! 	}
        else if (fmt[i] == '0' || fmt[i] == 't')
  	/* Unused.  */
  	;
        else
  	abort ();
      }
    return hash;
  }
  
! /* Like canon_hash but with no side effects.  */
  
! static unsigned
  safe_hash (rtx x, enum machine_mode mode)
  {
!   int save_do_not_record = do_not_record;
!   int save_hash_arg_in_memory = hash_arg_in_memory;
!   unsigned hash = canon_hash (x, mode);
!   hash_arg_in_memory = save_hash_arg_in_memory;
!   do_not_record = save_do_not_record;
!   return hash;
  }
  
  /* Return 1 iff X and Y would canonicalize into the same thing,
--- 2345,2403 ----
      {
        if (fmt[i] == 'e')
  	{
  	  /* If we are about to do the last recursive call
  	     needed at this level, change it into iteration.
  	     This function  is called enough to be worth it.  */
  	  if (i == 0)
  	    {
! 	      x = XEXP (x, i);
  	      goto repeat;
  	    }
! 
! 	  hash += hash_rtx (XEXP (x, i), 0, do_not_record_p,
! 			    hash_arg_in_memory_p, have_reg_qty);
  	}
+ 
        else if (fmt[i] == 'E')
  	for (j = 0; j < XVECLEN (x, i); j++)
! 	  {
! 	    hash += hash_rtx (XVECEXP (x, i, j), 0, do_not_record_p,
! 			      hash_arg_in_memory_p, have_reg_qty);
! 	  }
! 
        else if (fmt[i] == 's')
! 	hash += hash_rtx_string (XSTR (x, i));
        else if (fmt[i] == 'i')
! 	hash += (unsigned int) XINT (x, i);
        else if (fmt[i] == '0' || fmt[i] == 't')
  	/* Unused.  */
  	;
        else
  	abort ();
      }
+ 
    return hash;
  }
  
! /* Hash an rtx X for cse via hash_rtx.
!    Stores 1 in do_not_record if any subexpression is volatile.
!    Stores 1 in hash_arg_in_memory if X contains a mem rtx which
!    does not have the RTX_UNCHANGING_P bit set.  */
! 
! static inline unsigned
! canon_hash (rtx x, enum machine_mode mode)
! {
!   return hash_rtx (x, mode, &do_not_record, &hash_arg_in_memory, true);
! }
! 
! /* Like canon_hash but with no side effects, i.e. do_not_record
!    and hash_arg_in_memory are not changed.  */
  
! static inline unsigned
  safe_hash (rtx x, enum machine_mode mode)
  {
!   int dummy_do_not_record;
!   return hash_rtx (x, mode, &dummy_do_not_record, NULL, true);
  }
  
  /* Return 1 iff X and Y would canonicalize into the same thing,
*************** safe_hash (rtx x, enum machine_mode mode
*** 2363,2378 ****
     and Y was found in the hash table.  We check register refs
     in Y for being marked as valid.
  
!    If EQUAL_VALUES is nonzero, we allow a register to match a constant value
!    that is known to be in the register.  Ordinarily, we don't allow them
!    to match, because letting them match would cause unpredictable results
!    in all the places that search a hash table chain for an equivalent
!    for a given value.  A possible equivalent that has different structure
!    has its hash code computed from different data.  Whether the hash code
!    is the same as that of the given value is pure luck.  */
  
! static int
! exp_equiv_p (rtx x, rtx y, int validate, int equal_values)
  {
    int i, j;
    enum rtx_code code;
--- 2407,2416 ----
     and Y was found in the hash table.  We check register refs
     in Y for being marked as valid.
  
!    If FOR_GCSE is true, we compare X and Y for equivalence for GCSE.  */
  
! int
! exp_equiv_p (rtx x, rtx y, int validate, bool for_gcse)
  {
    int i, j;
    enum rtx_code code;
*************** exp_equiv_p (rtx x, rtx y, int validate,
*** 2382,2423 ****
       if VALIDATE is nonzero.  */
    if (x == y && !validate)
      return 1;
    if (x == 0 || y == 0)
      return x == y;
  
    code = GET_CODE (x);
    if (code != GET_CODE (y))
!     {
!       if (!equal_values)
! 	return 0;
! 
!       /* If X is a constant and Y is a register or vice versa, they may be
! 	 equivalent.  We only have to validate if Y is a register.  */
!       if (CONSTANT_P (x) && REG_P (y)
! 	  && REGNO_QTY_VALID_P (REGNO (y)))
! 	{
! 	  int y_q = REG_QTY (REGNO (y));
! 	  struct qty_table_elem *y_ent = &qty_table[y_q];
! 
! 	  if (GET_MODE (y) == y_ent->mode
! 	      && rtx_equal_p (x, y_ent->const_rtx)
! 	      && (! validate || REG_IN_TABLE (REGNO (y)) == REG_TICK (REGNO (y))))
! 	    return 1;
! 	}
! 
!       if (CONSTANT_P (y) && code == REG
! 	  && REGNO_QTY_VALID_P (REGNO (x)))
! 	{
! 	  int x_q = REG_QTY (REGNO (x));
! 	  struct qty_table_elem *x_ent = &qty_table[x_q];
! 
! 	  if (GET_MODE (x) == x_ent->mode
! 	      && rtx_equal_p (y, x_ent->const_rtx))
! 	    return 1;
! 	}
! 
!       return 0;
!     }
  
    /* (MULT:SI x y) and (MULT:HI x y) are NOT equivalent.  */
    if (GET_MODE (x) != GET_MODE (y))
--- 2420,2432 ----
       if VALIDATE is nonzero.  */
    if (x == y && !validate)
      return 1;
+ 
    if (x == 0 || y == 0)
      return x == y;
  
    code = GET_CODE (x);
    if (code != GET_CODE (y))
!     return 0;
  
    /* (MULT:SI x y) and (MULT:HI x y) are NOT equivalent.  */
    if (GET_MODE (x) != GET_MODE (y))
*************** exp_equiv_p (rtx x, rtx y, int validate,
*** 2437,2465 ****
        return XSTR (x, 0) == XSTR (y, 0);
  
      case REG:
!       {
! 	unsigned int regno = REGNO (y);
! 	unsigned int endregno
! 	  = regno + (regno >= FIRST_PSEUDO_REGISTER ? 1
! 		     : hard_regno_nregs[regno][GET_MODE (y)]);
! 	unsigned int i;
! 
! 	/* If the quantities are not the same, the expressions are not
! 	   equivalent.  If there are and we are not to validate, they
! 	   are equivalent.  Otherwise, ensure all regs are up-to-date.  */
  
! 	if (REG_QTY (REGNO (x)) != REG_QTY (regno))
! 	  return 0;
  
- 	if (! validate)
  	  return 1;
  
! 	for (i = regno; i < endregno; i++)
! 	  if (REG_IN_TABLE (i) != REG_TICK (i))
  	    return 0;
  
! 	return 1;
!       }
  
      /*  For commutative operations, check both orders.  */
      case PLUS:
--- 2446,2493 ----
        return XSTR (x, 0) == XSTR (y, 0);
  
      case REG:
!       if (for_gcse)
! 	return REGNO (x) == REGNO (y);
!       else
! 	{
! 	  unsigned int regno = REGNO (y);
! 	  unsigned int i;
! 	  unsigned int endregno
! 	    = regno + (regno >= FIRST_PSEUDO_REGISTER ? 1
! 		       : hard_regno_nregs[regno][GET_MODE (y)]);
! 
! 	  /* If the quantities are not the same, the expressions are not
! 	     equivalent.  If there are and we are not to validate, they
! 	     are equivalent.  Otherwise, ensure all regs are up-to-date.  */
  
! 	  if (REG_QTY (REGNO (x)) != REG_QTY (regno))
! 	    return 0;
! 
! 	  if (! validate)
! 	    return 1;
! 
! 	  for (i = regno; i < endregno; i++)
! 	    if (REG_IN_TABLE (i) != REG_TICK (i))
! 	      return 0;
  
  	  return 1;
+ 	}
  
!     case MEM:
!       if (for_gcse)
! 	{
! 	  /* Can't merge two expressions in different alias sets, since we
! 	     can decide that the expression is transparent in a block when
! 	     it isn't, due to it being set with the different alias set.  */
! 	  if (MEM_ALIAS_SET (x) != MEM_ALIAS_SET (y))
  	    return 0;
  
! 	  /* A volatile mem should not be considered equivalent to any
! 	     other.  */
! 	  if (MEM_VOLATILE_P (x) || MEM_VOLATILE_P (y))
! 	    return 0;
! 	}
!       break;
  
      /*  For commutative operations, check both orders.  */
      case PLUS:
*************** exp_equiv_p (rtx x, rtx y, int validate,
*** 2469,2481 ****
      case XOR:
      case NE:
      case EQ:
!       return ((exp_equiv_p (XEXP (x, 0), XEXP (y, 0), validate, equal_values)
  	       && exp_equiv_p (XEXP (x, 1), XEXP (y, 1),
! 			       validate, equal_values))
  	      || (exp_equiv_p (XEXP (x, 0), XEXP (y, 1),
! 			       validate, equal_values)
  		  && exp_equiv_p (XEXP (x, 1), XEXP (y, 0),
! 				  validate, equal_values)));
  
      case ASM_OPERANDS:
        /* We don't use the generic code below because we want to
--- 2497,2510 ----
      case XOR:
      case NE:
      case EQ:
!       return ((exp_equiv_p (XEXP (x, 0), XEXP (y, 0),
! 			     validate, for_gcse)
  	       && exp_equiv_p (XEXP (x, 1), XEXP (y, 1),
! 				validate, for_gcse))
  	      || (exp_equiv_p (XEXP (x, 0), XEXP (y, 1),
! 				validate, for_gcse)
  		  && exp_equiv_p (XEXP (x, 1), XEXP (y, 0),
! 				   validate, for_gcse)));
  
      case ASM_OPERANDS:
        /* We don't use the generic code below because we want to
*************** exp_equiv_p (rtx x, rtx y, int validate,
*** 2498,2504 ****
  	  for (i = ASM_OPERANDS_INPUT_LENGTH (x) - 1; i >= 0; i--)
  	    if (! exp_equiv_p (ASM_OPERANDS_INPUT (x, i),
  			       ASM_OPERANDS_INPUT (y, i),
! 			       validate, equal_values)
  		|| strcmp (ASM_OPERANDS_INPUT_CONSTRAINT (x, i),
  			   ASM_OPERANDS_INPUT_CONSTRAINT (y, i)))
  	      return 0;
--- 2527,2533 ----
  	  for (i = ASM_OPERANDS_INPUT_LENGTH (x) - 1; i >= 0; i--)
  	    if (! exp_equiv_p (ASM_OPERANDS_INPUT (x, i),
  			       ASM_OPERANDS_INPUT (y, i),
! 			       validate, for_gcse)
  		|| strcmp (ASM_OPERANDS_INPUT_CONSTRAINT (x, i),
  			   ASM_OPERANDS_INPUT_CONSTRAINT (y, i)))
  	      return 0;
*************** exp_equiv_p (rtx x, rtx y, int validate,
*** 2511,2517 ****
      }
  
    /* Compare the elements.  If any pair of corresponding elements
!      fail to match, return 0 for the whole things.  */
  
    fmt = GET_RTX_FORMAT (code);
    for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
--- 2540,2546 ----
      }
  
    /* Compare the elements.  If any pair of corresponding elements
!      fail to match, return 0 for the whole thing.  */
  
    fmt = GET_RTX_FORMAT (code);
    for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
*************** exp_equiv_p (rtx x, rtx y, int validate,
*** 2519,2525 ****
        switch (fmt[i])
  	{
  	case 'e':
! 	  if (! exp_equiv_p (XEXP (x, i), XEXP (y, i), validate, equal_values))
  	    return 0;
  	  break;
  
--- 2548,2555 ----
        switch (fmt[i])
  	{
  	case 'e':
! 	  if (! exp_equiv_p (XEXP (x, i), XEXP (y, i),
! 			      validate, for_gcse))
  	    return 0;
  	  break;
  
*************** exp_equiv_p (rtx x, rtx y, int validate,
*** 2528,2534 ****
  	    return 0;
  	  for (j = 0; j < XVECLEN (x, i); j++)
  	    if (! exp_equiv_p (XVECEXP (x, i, j), XVECEXP (y, i, j),
! 			       validate, equal_values))
  	      return 0;
  	  break;
  
--- 2558,2564 ----
  	    return 0;
  	  for (j = 0; j < XVECLEN (x, i); j++)
  	    if (! exp_equiv_p (XVECEXP (x, i, j), XVECEXP (y, i, j),
! 				validate, for_gcse))
  	      return 0;
  	  break;
  
*************** find_best_addr (rtx insn, rtx *loc, enum
*** 2827,2833 ****
  	    if (! p->flag)
  	      {
  		if ((REG_P (p->exp)
! 		     || exp_equiv_p (p->exp, p->exp, 1, 0))
  		    && ((exp_cost = address_cost (p->exp, mode)) < best_addr_cost
  			|| (exp_cost == best_addr_cost
  			    && ((p->cost + 1) >> 1) > best_rtx_cost)))
--- 2857,2863 ----
  	    if (! p->flag)
  	      {
  		if ((REG_P (p->exp)
! 		     || exp_equiv_p (p->exp, p->exp, 1, false))
  		    && ((exp_cost = address_cost (p->exp, mode)) < best_addr_cost
  			|| (exp_cost == best_addr_cost
  			    && ((p->cost + 1) >> 1) > best_rtx_cost)))
*************** find_best_addr (rtx insn, rtx *loc, enum
*** 2903,2909 ****
  	       p = p->next_same_value, count++)
  	    if (! p->flag
  		&& (REG_P (p->exp)
! 		    || exp_equiv_p (p->exp, p->exp, 1, 0)))
  	      {
  		rtx new = simplify_gen_binary (GET_CODE (*loc), Pmode,
  					       p->exp, op1);
--- 2933,2939 ----
  	       p = p->next_same_value, count++)
  	    if (! p->flag
  		&& (REG_P (p->exp)
! 		    || exp_equiv_p (p->exp, p->exp, 1, false)))
  	      {
  		rtx new = simplify_gen_binary (GET_CODE (*loc), Pmode,
  					       p->exp, op1);
*************** find_comparison_args (enum rtx_code code
*** 3012,3019 ****
        if (x == 0)
  	/* Look up ARG1 in the hash table and see if it has an equivalence
  	   that lets us see what is being compared.  */
! 	p = lookup (arg1, safe_hash (arg1, GET_MODE (arg1)) & HASH_MASK,
! 		    GET_MODE (arg1));
        if (p)
  	{
  	  p = p->first_same_value;
--- 3042,3048 ----
        if (x == 0)
  	/* Look up ARG1 in the hash table and see if it has an equivalence
  	   that lets us see what is being compared.  */
! 	p = lookup (arg1, SAFE_HASH (arg1, GET_MODE (arg1)), GET_MODE (arg1));
        if (p)
  	{
  	  p = p->first_same_value;
*************** find_comparison_args (enum rtx_code code
*** 3038,3044 ****
  #endif
  
  	  /* If the entry isn't valid, skip it.  */
! 	  if (! exp_equiv_p (p->exp, p->exp, 1, 0))
  	    continue;
  
  	  if (GET_CODE (p->exp) == COMPARE
--- 3067,3073 ----
  #endif
  
  	  /* If the entry isn't valid, skip it.  */
! 	  if (! exp_equiv_p (p->exp, p->exp, 1, false))
  	    continue;
  
  	  if (GET_CODE (p->exp) == COMPARE
*************** fold_rtx (rtx x, rtx insn)
*** 3235,3241 ****
  
  		if (GET_CODE (elt->exp) == SUBREG
  		    && GET_MODE (SUBREG_REG (elt->exp)) == mode
! 		    && exp_equiv_p (elt->exp, elt->exp, 1, 0))
  		  return copy_rtx (SUBREG_REG (elt->exp));
  	      }
  
--- 3264,3270 ----
  
  		if (GET_CODE (elt->exp) == SUBREG
  		    && GET_MODE (SUBREG_REG (elt->exp)) == mode
! 		    && exp_equiv_p (elt->exp, elt->exp, 1, false))
  		  return copy_rtx (SUBREG_REG (elt->exp));
  	      }
  
*************** fold_rtx (rtx x, rtx insn)
*** 3264,3271 ****
  	{
  	  struct table_elt *elt;
  
- 	  /* We can use HASH here since we know that canon_hash won't be
- 	     called.  */
  	  elt = lookup (folded_arg0,
  			HASH (folded_arg0, GET_MODE (folded_arg0)),
  			GET_MODE (folded_arg0));
--- 3293,3298 ----
*************** fold_rtx (rtx x, rtx insn)
*** 3370,3376 ****
  		         && GET_MODE (SUBREG_REG (elt->exp)) == mode
  		         && (GET_MODE_SIZE (GET_MODE (folded_arg0))
  			     <= UNITS_PER_WORD)
! 		         && exp_equiv_p (elt->exp, elt->exp, 1, 0))
  		  new = copy_rtx (SUBREG_REG (elt->exp));
  
  	        if (new)
--- 3397,3403 ----
  		         && GET_MODE (SUBREG_REG (elt->exp)) == mode
  		         && (GET_MODE_SIZE (GET_MODE (folded_arg0))
  			     <= UNITS_PER_WORD)
! 		         && exp_equiv_p (elt->exp, elt->exp, 1, false))
  		  new = copy_rtx (SUBREG_REG (elt->exp));
  
  	        if (new)
*************** fold_rtx (rtx x, rtx insn)
*** 3829,3839 ****
  		      && (REG_QTY (REGNO (folded_arg0))
  			  == REG_QTY (REGNO (folded_arg1))))
  		  || ((p0 = lookup (folded_arg0,
! 				    (safe_hash (folded_arg0, mode_arg0)
! 				     & HASH_MASK), mode_arg0))
  		      && (p1 = lookup (folded_arg1,
! 				       (safe_hash (folded_arg1, mode_arg0)
! 					& HASH_MASK), mode_arg0))
  		      && p0->first_same_value == p1->first_same_value))
  		{
  		  /* Sadly two equal NaNs are not equivalent.  */
--- 3856,3866 ----
  		      && (REG_QTY (REGNO (folded_arg0))
  			  == REG_QTY (REGNO (folded_arg1))))
  		  || ((p0 = lookup (folded_arg0,
! 				    SAFE_HASH (folded_arg0, mode_arg0),
! 				    mode_arg0))
  		      && (p1 = lookup (folded_arg1,
! 				       SAFE_HASH (folded_arg1, mode_arg0),
! 				       mode_arg0))
  		      && p0->first_same_value == p1->first_same_value))
  		{
  		  /* Sadly two equal NaNs are not equivalent.  */
*************** fold_rtx (rtx x, rtx insn)
*** 4007,4014 ****
  	    {
  	      rtx new_const = GEN_INT (-INTVAL (const_arg1));
  	      struct table_elt *p
! 		= lookup (new_const, safe_hash (new_const, mode) & HASH_MASK,
! 			  mode);
  
  	      if (p)
  		for (p = p->first_same_value; p; p = p->next_same_value)
--- 4034,4040 ----
  	    {
  	      rtx new_const = GEN_INT (-INTVAL (const_arg1));
  	      struct table_elt *p
! 		= lookup (new_const, SAFE_HASH (new_const, mode), mode);
  
  	      if (p)
  		for (p = p->first_same_value; p; p = p->next_same_value)
*************** equiv_constant (rtx x)
*** 4195,4201 ****
        if (CONSTANT_P (x))
  	return x;
  
!       elt = lookup (x, safe_hash (x, GET_MODE (x)) & HASH_MASK, GET_MODE (x));
        if (elt == 0)
  	return 0;
  
--- 4221,4227 ----
        if (CONSTANT_P (x))
  	return x;
  
!       elt = lookup (x, SAFE_HASH (x, GET_MODE (x)), GET_MODE (x));
        if (elt == 0)
  	return 0;
  
*************** cse_insn (rtx insn, rtx libcall_insn)
*** 5182,5188 ****
  	  /* If the expression is not valid, ignore it.  Then we do not
  	     have to check for validity below.  In most cases, we can use
  	     `rtx_equal_p', since canonicalization has already been done.  */
! 	  if (code != REG && ! exp_equiv_p (p->exp, p->exp, 1, 0))
  	    continue;
  
  	  /* Also skip paradoxical subregs, unless that's what we're
--- 5208,5214 ----
  	  /* If the expression is not valid, ignore it.  Then we do not
  	     have to check for validity below.  In most cases, we can use
  	     `rtx_equal_p', since canonicalization has already been done.  */
! 	  if (code != REG && ! exp_equiv_p (p->exp, p->exp, 1, false))
  	    continue;
  
  	  /* Also skip paradoxical subregs, unless that's what we're
*************** cse_insn (rtx insn, rtx libcall_insn)
*** 5279,5285 ****
  
  	  /* Skip invalid entries.  */
  	  while (elt && !REG_P (elt->exp)
! 		 && ! exp_equiv_p (elt->exp, elt->exp, 1, 0))
  	    elt = elt->next_same_value;
  
  	  /* A paradoxical subreg would be bad here: it'll be the right
--- 5305,5311 ----
  
  	  /* Skip invalid entries.  */
  	  while (elt && !REG_P (elt->exp)
! 		 && ! exp_equiv_p (elt->exp, elt->exp, 1, false))
  	    elt = elt->next_same_value;
  
  	  /* A paradoxical subreg would be bad here: it'll be the right
*************** cse_insn (rtx insn, rtx libcall_insn)
*** 6006,6012 ****
  
  		/* Ignore invalid entries.  */
  		if (!REG_P (elt->exp)
! 		    && ! exp_equiv_p (elt->exp, elt->exp, 1, 0))
  		  continue;
  
  		/* We may have already been playing subreg games.  If the
--- 6032,6038 ----
  
  		/* Ignore invalid entries.  */
  		if (!REG_P (elt->exp)
! 		    && ! exp_equiv_p (elt->exp, elt->exp, 1, false))
  		  continue;
  
  		/* We may have already been playing subreg games.  If the
*************** cse_insn (rtx insn, rtx libcall_insn)
*** 6059,6065 ****
  		/* Ignore invalid entries.  */
  		while (classp
  		       && !REG_P (classp->exp)
! 		       && ! exp_equiv_p (classp->exp, classp->exp, 1, 0))
  		  classp = classp->next_same_value;
  	      }
  	  }
--- 6085,6091 ----
  		/* Ignore invalid entries.  */
  		while (classp
  		       && !REG_P (classp->exp)
! 		       && ! exp_equiv_p (classp->exp, classp->exp, 1, false))
  		  classp = classp->next_same_value;
  	      }
  	  }
Index: cselib.c
===================================================================
RCS file: /cvs/gcc/gcc/gcc/cselib.c,v
retrieving revision 1.49
diff -c -3 -p -r1.49 cselib.c
*** cselib.c	9 Jul 2004 03:29:26 -0000	1.49
--- cselib.c	18 Aug 2004 17:51:30 -0000
*************** static int discard_useless_locs (void **
*** 55,61 ****
  static int discard_useless_values (void **, void *);
  static void remove_useless_values (void);
  static rtx wrap_constant (enum machine_mode, rtx);
! static unsigned int hash_rtx (rtx, enum machine_mode, int);
  static cselib_val *new_cselib_val (unsigned int, enum machine_mode);
  static void add_mem_for_addr (cselib_val *, cselib_val *, rtx);
  static cselib_val *cselib_lookup_mem (rtx, int);
--- 55,61 ----
  static int discard_useless_values (void **, void *);
  static void remove_useless_values (void);
  static rtx wrap_constant (enum machine_mode, rtx);
! static unsigned int cselib_hash_rtx (rtx, enum machine_mode, int);
  static cselib_val *new_cselib_val (unsigned int, enum machine_mode);
  static void add_mem_for_addr (cselib_val *, cselib_val *, rtx);
  static cselib_val *cselib_lookup_mem (rtx, int);
*************** entry_and_rtx_equal_p (const void *entry
*** 257,264 ****
  }
  
  /* The hash function for our hash table.  The value is always computed with
!    hash_rtx when adding an element; this function just extracts the hash
!    value from a cselib_val structure.  */
  
  static hashval_t
  get_value_hash (const void *entry)
--- 257,264 ----
  }
  
  /* The hash function for our hash table.  The value is always computed with
!    cselib_hash_rtx when adding an element; this function just extracts the
!    hash value from a cselib_val structure.  */
  
  static hashval_t
  get_value_hash (const void *entry)
*************** wrap_constant (enum machine_mode mode, r
*** 554,560 ****
     otherwise the mode of X is used.  */
  
  static unsigned int
! hash_rtx (rtx x, enum machine_mode mode, int create)
  {
    cselib_val *e;
    int i, j;
--- 554,560 ----
     otherwise the mode of X is used.  */
  
  static unsigned int
! cselib_hash_rtx (rtx x, enum machine_mode mode, int create)
  {
    cselib_val *e;
    int i, j;
*************** hash_rtx (rtx x, enum machine_mode mode,
*** 600,606 ****
  	for (i = 0; i < units; ++i)
  	  {
  	    elt = CONST_VECTOR_ELT (x, i);
! 	    hash += hash_rtx (elt, GET_MODE (elt), 0);
  	  }
  
  	return hash;
--- 600,606 ----
  	for (i = 0; i < units; ++i)
  	  {
  	    elt = CONST_VECTOR_ELT (x, i);
! 	    hash += cselib_hash_rtx (elt, GET_MODE (elt), 0);
  	  }
  
  	return hash;
*************** hash_rtx (rtx x, enum machine_mode mode,
*** 646,652 ****
        if (fmt[i] == 'e')
  	{
  	  rtx tem = XEXP (x, i);
! 	  unsigned int tem_hash = hash_rtx (tem, 0, create);
  
  	  if (tem_hash == 0)
  	    return 0;
--- 646,652 ----
        if (fmt[i] == 'e')
  	{
  	  rtx tem = XEXP (x, i);
! 	  unsigned int tem_hash = cselib_hash_rtx (tem, 0, create);
  
  	  if (tem_hash == 0)
  	    return 0;
*************** hash_rtx (rtx x, enum machine_mode mode,
*** 656,662 ****
        else if (fmt[i] == 'E')
  	for (j = 0; j < XVECLEN (x, i); j++)
  	  {
! 	    unsigned int tem_hash = hash_rtx (XVECEXP (x, i, j), 0, create);
  
  	    if (tem_hash == 0)
  	      return 0;
--- 656,662 ----
        else if (fmt[i] == 'E')
  	for (j = 0; j < XVECLEN (x, i); j++)
  	  {
! 	    unsigned int tem_hash = cselib_hash_rtx (XVECEXP (x, i, j), 0, create);
  
  	    if (tem_hash == 0)
  	      return 0;
*************** cselib_lookup (rtx x, enum machine_mode 
*** 926,932 ****
    if (MEM_P (x))
      return cselib_lookup_mem (x, create);
  
!   hashval = hash_rtx (x, mode, create);
    /* Can't even create if hashing is not possible.  */
    if (! hashval)
      return 0;
--- 926,932 ----
    if (MEM_P (x))
      return cselib_lookup_mem (x, create);
  
!   hashval = cselib_hash_rtx (x, mode, create);
    /* Can't even create if hashing is not possible.  */
    if (! hashval)
      return 0;
Index: gcse.c
===================================================================
RCS file: /cvs/gcc/gcc/gcc/gcse.c,v
retrieving revision 1.309
diff -c -3 -p -r1.309 gcse.c
*** gcse.c	9 Aug 2004 16:58:42 -0000	1.309
--- gcse.c	18 Aug 2004 17:51:30 -0000
*************** static sbitmap *reg_set_in_block;
*** 495,505 ****
  /* Array, indexed by basic block number for a list of insns which modify
     memory within that block.  */
  static rtx * modify_mem_list;
! bitmap modify_mem_list_set;
  
  /* This array parallels modify_mem_list, but is kept canonicalized.  */
  static rtx * canon_modify_mem_list;
! bitmap canon_modify_mem_list_set;
  /* Various variables for statistics gathering.  */
  
  /* Memory used in a pass.
--- 495,506 ----
  /* Array, indexed by basic block number for a list of insns which modify
     memory within that block.  */
  static rtx * modify_mem_list;
! static bitmap modify_mem_list_set;
  
  /* This array parallels modify_mem_list, but is kept canonicalized.  */
  static rtx * canon_modify_mem_list;
! static bitmap canon_modify_mem_list_set;
! 
  /* Various variables for statistics gathering.  */
  
  /* Memory used in a pass.
*************** static void insert_expr_in_table (rtx, e
*** 564,571 ****
  				  struct hash_table *);
  static void insert_set_in_table (rtx, rtx, struct hash_table *);
  static unsigned int hash_expr (rtx, enum machine_mode, int *, int);
- static unsigned int hash_expr_1 (rtx, enum machine_mode, int *);
- static unsigned int hash_string_1 (const char *);
  static unsigned int hash_set (int, int);
  static int expr_equiv_p (rtx, rtx);
  static void record_last_reg_set_info (rtx, int);
--- 565,570 ----
*************** static void alloc_hash_table (int, struc
*** 576,582 ****
  static void free_hash_table (struct hash_table *);
  static void compute_hash_table_work (struct hash_table *);
  static void dump_hash_table (FILE *, const char *, struct hash_table *);
- static struct expr *lookup_expr (rtx, struct hash_table *);
  static struct expr *lookup_set (unsigned int, struct hash_table *);
  static struct expr *next_set (unsigned int, struct expr *);
  static void reset_opr_set_tables (void);
--- 575,580 ----
*************** oprs_available_p (rtx x, rtx insn)
*** 1462,1470 ****
     MODE is only used if X is a CONST_INT.  DO_NOT_RECORD_P is a boolean
     indicating if a volatile operand is found or if the expression contains
     something we don't want to insert in the table.  HASH_TABLE_SIZE is
!    the current size of the hash table to be probed.
! 
!    ??? One might want to merge this with canon_hash.  Later.  */
  
  static unsigned int
  hash_expr (rtx x, enum machine_mode mode, int *do_not_record_p,
--- 1460,1466 ----
     MODE is only used if X is a CONST_INT.  DO_NOT_RECORD_P is a boolean
     indicating if a volatile operand is found or if the expression contains
     something we don't want to insert in the table.  HASH_TABLE_SIZE is
!    the current size of the hash table to be probed.  */
  
  static unsigned int
  hash_expr (rtx x, enum machine_mode mode, int *do_not_record_p,
*************** hash_expr (rtx x, enum machine_mode mode
*** 1474,1681 ****
  
    *do_not_record_p = 0;
  
!   hash = hash_expr_1 (x, mode, do_not_record_p);
    return hash % hash_table_size;
  }
  
- /* Hash a string.  Just add its bytes up.  */
- 
- static inline unsigned
- hash_string_1 (const char *ps)
- {
-   unsigned hash = 0;
-   const unsigned char *p = (const unsigned char *) ps;
- 
-   if (p)
-     while (*p)
-       hash += *p++;
- 
-   return hash;
- }
- 
- /* Subroutine of hash_expr to do the actual work.  */
- 
- static unsigned int
- hash_expr_1 (rtx x, enum machine_mode mode, int *do_not_record_p)
- {
-   int i, j;
-   unsigned hash = 0;
-   enum rtx_code code;
-   const char *fmt;
- 
-   if (x == 0)
-     return hash;
- 
-   /* Used to turn recursion into iteration.  We can't rely on GCC's
-      tail-recursion elimination since we need to keep accumulating values
-      in HASH.  */
-  repeat:
- 
-   code = GET_CODE (x);
-   switch (code)
-     {
-     case REG:
-       hash += ((unsigned int) REG << 7) + REGNO (x);
-       return hash;
- 
-     case CONST_INT:
-       hash += (((unsigned int) CONST_INT << 7) + (unsigned int) mode
- 	       + (unsigned int) INTVAL (x));
-       return hash;
- 
-     case CONST_DOUBLE:
-       /* This is like the general case, except that it only counts
- 	 the integers representing the constant.  */
-       hash += (unsigned int) code + (unsigned int) GET_MODE (x);
-       if (GET_MODE (x) != VOIDmode)
- 	for (i = 2; i < GET_RTX_LENGTH (CONST_DOUBLE); i++)
- 	  hash += (unsigned int) XWINT (x, i);
-       else
- 	hash += ((unsigned int) CONST_DOUBLE_LOW (x)
- 		 + (unsigned int) CONST_DOUBLE_HIGH (x));
-       return hash;
- 
-     case CONST_VECTOR:
-       {
- 	int units;
- 	rtx elt;
- 
- 	units = CONST_VECTOR_NUNITS (x);
- 
- 	for (i = 0; i < units; ++i)
- 	  {
- 	    elt = CONST_VECTOR_ELT (x, i);
- 	    hash += hash_expr_1 (elt, GET_MODE (elt), do_not_record_p);
- 	  }
- 
- 	return hash;
-       }
- 
-       /* Assume there is only one rtx object for any given label.  */
-     case LABEL_REF:
-       /* We don't hash on the address of the CODE_LABEL to avoid bootstrap
- 	 differences and differences between each stage's debugging dumps.  */
-       hash += (((unsigned int) LABEL_REF << 7)
- 	       + CODE_LABEL_NUMBER (XEXP (x, 0)));
-       return hash;
- 
-     case SYMBOL_REF:
-       {
- 	/* Don't hash on the symbol's address to avoid bootstrap differences.
- 	   Different hash values may cause expressions to be recorded in
- 	   different orders and thus different registers to be used in the
- 	   final assembler.  This also avoids differences in the dump files
- 	   between various stages.  */
- 	unsigned int h = 0;
- 	const unsigned char *p = (const unsigned char *) XSTR (x, 0);
- 
- 	while (*p)
- 	  h += (h << 7) + *p++; /* ??? revisit */
- 
- 	hash += ((unsigned int) SYMBOL_REF << 7) + h;
- 	return hash;
-       }
- 
-     case MEM:
-       if (MEM_VOLATILE_P (x))
- 	{
- 	  *do_not_record_p = 1;
- 	  return 0;
- 	}
- 
-       hash += (unsigned int) MEM;
-       /* We used alias set for hashing, but this is not good, since the alias
- 	 set may differ in -fprofile-arcs and -fbranch-probabilities compilation
- 	 causing the profiles to fail to match.  */
-       x = XEXP (x, 0);
-       goto repeat;
- 
-     case PRE_DEC:
-     case PRE_INC:
-     case POST_DEC:
-     case POST_INC:
-     case PC:
-     case CC0:
-     case CALL:
-     case UNSPEC_VOLATILE:
-       *do_not_record_p = 1;
-       return 0;
- 
-     case ASM_OPERANDS:
-       if (MEM_VOLATILE_P (x))
- 	{
- 	  *do_not_record_p = 1;
- 	  return 0;
- 	}
-       else
- 	{
- 	  /* We don't want to take the filename and line into account.  */
- 	  hash += (unsigned) code + (unsigned) GET_MODE (x)
- 	    + hash_string_1 (ASM_OPERANDS_TEMPLATE (x))
- 	    + hash_string_1 (ASM_OPERANDS_OUTPUT_CONSTRAINT (x))
- 	    + (unsigned) ASM_OPERANDS_OUTPUT_IDX (x);
- 
- 	  if (ASM_OPERANDS_INPUT_LENGTH (x))
- 	    {
- 	      for (i = 1; i < ASM_OPERANDS_INPUT_LENGTH (x); i++)
- 		{
- 		  hash += (hash_expr_1 (ASM_OPERANDS_INPUT (x, i),
- 					GET_MODE (ASM_OPERANDS_INPUT (x, i)),
- 					do_not_record_p)
- 			   + hash_string_1 (ASM_OPERANDS_INPUT_CONSTRAINT
- 					    (x, i)));
- 		}
- 
- 	      hash += hash_string_1 (ASM_OPERANDS_INPUT_CONSTRAINT (x, 0));
- 	      x = ASM_OPERANDS_INPUT (x, 0);
- 	      mode = GET_MODE (x);
- 	      goto repeat;
- 	    }
- 	  return hash;
- 	}
- 
-     default:
-       break;
-     }
- 
-   hash += (unsigned) code + (unsigned) GET_MODE (x);
-   for (i = GET_RTX_LENGTH (code) - 1, fmt = GET_RTX_FORMAT (code); i >= 0; i--)
-     {
-       if (fmt[i] == 'e')
- 	{
- 	  /* If we are about to do the last recursive call
- 	     needed at this level, change it into iteration.
- 	     This function is called enough to be worth it.  */
- 	  if (i == 0)
- 	    {
- 	      x = XEXP (x, i);
- 	      goto repeat;
- 	    }
- 
- 	  hash += hash_expr_1 (XEXP (x, i), 0, do_not_record_p);
- 	  if (*do_not_record_p)
- 	    return 0;
- 	}
- 
-       else if (fmt[i] == 'E')
- 	for (j = 0; j < XVECLEN (x, i); j++)
- 	  {
- 	    hash += hash_expr_1 (XVECEXP (x, i, j), 0, do_not_record_p);
- 	    if (*do_not_record_p)
- 	      return 0;
- 	  }
- 
-       else if (fmt[i] == 's')
- 	hash += hash_string_1 (XSTR (x, i));
-       else if (fmt[i] == 'i')
- 	hash += (unsigned int) XINT (x, i);
-       else
- 	abort ();
-     }
- 
-   return hash;
- }
- 
  /* Hash a set of register REGNO.
  
     Sets are hashed on the register that is set.  This simplifies the PRE copy
--- 1470,1480 ----
  
    *do_not_record_p = 0;
  
!   hash = hash_rtx (x, mode, do_not_record_p,
! 		   NULL,  /*have_reg_qty=*/false);
    return hash % hash_table_size;
  }
  
  /* Hash a set of register REGNO.
  
     Sets are hashed on the register that is set.  This simplifies the PRE copy
*************** hash_set (int regno, int hash_table_size
*** 1692,1839 ****
    return hash % hash_table_size;
  }
  
! /* Return nonzero if exp1 is equivalent to exp2.
!    ??? Borrowed from cse.c.  Might want to remerge with cse.c.  Later.  */
  
  static int
  expr_equiv_p (rtx x, rtx y)
  {
!   int i, j;
!   enum rtx_code code;
!   const char *fmt;
! 
!   if (x == y)
!     return 1;
! 
!   if (x == 0 || y == 0)
!     return 0;
! 
!   code = GET_CODE (x);
!   if (code != GET_CODE (y))
!     return 0;
! 
!   /* (MULT:SI x y) and (MULT:HI x y) are NOT equivalent.  */
!   if (GET_MODE (x) != GET_MODE (y))
!     return 0;
! 
!   switch (code)
!     {
!     case PC:
!     case CC0:
!     case CONST_INT:
!       return 0;
! 
!     case LABEL_REF:
!       return XEXP (x, 0) == XEXP (y, 0);
! 
!     case SYMBOL_REF:
!       return XSTR (x, 0) == XSTR (y, 0);
! 
!     case REG:
!       return REGNO (x) == REGNO (y);
! 
!     case MEM:
!       /* Can't merge two expressions in different alias sets, since we can
! 	 decide that the expression is transparent in a block when it isn't,
! 	 due to it being set with the different alias set.  */
!       if (MEM_ALIAS_SET (x) != MEM_ALIAS_SET (y))
! 	return 0;
! 
!       /* A volatile mem should not be considered equivalent to any other.  */
!       if (MEM_VOLATILE_P (x) || MEM_VOLATILE_P (y))
! 	return 0;
!       break;
! 
!     /*  For commutative operations, check both orders.  */
!     case PLUS:
!     case MULT:
!     case AND:
!     case IOR:
!     case XOR:
!     case NE:
!     case EQ:
!       return ((expr_equiv_p (XEXP (x, 0), XEXP (y, 0))
! 	       && expr_equiv_p (XEXP (x, 1), XEXP (y, 1)))
! 	      || (expr_equiv_p (XEXP (x, 0), XEXP (y, 1))
! 		  && expr_equiv_p (XEXP (x, 1), XEXP (y, 0))));
! 
!     case ASM_OPERANDS:
!       /* We don't use the generic code below because we want to
! 	 disregard filename and line numbers.  */
! 
!       /* A volatile asm isn't equivalent to any other.  */
!       if (MEM_VOLATILE_P (x) || MEM_VOLATILE_P (y))
! 	return 0;
! 
!       if (GET_MODE (x) != GET_MODE (y)
! 	  || strcmp (ASM_OPERANDS_TEMPLATE (x), ASM_OPERANDS_TEMPLATE (y))
! 	  || strcmp (ASM_OPERANDS_OUTPUT_CONSTRAINT (x),
! 		     ASM_OPERANDS_OUTPUT_CONSTRAINT (y))
! 	  || ASM_OPERANDS_OUTPUT_IDX (x) != ASM_OPERANDS_OUTPUT_IDX (y)
! 	  || ASM_OPERANDS_INPUT_LENGTH (x) != ASM_OPERANDS_INPUT_LENGTH (y))
! 	return 0;
! 
!       if (ASM_OPERANDS_INPUT_LENGTH (x))
! 	{
! 	  for (i = ASM_OPERANDS_INPUT_LENGTH (x) - 1; i >= 0; i--)
! 	    if (! expr_equiv_p (ASM_OPERANDS_INPUT (x, i),
! 				ASM_OPERANDS_INPUT (y, i))
! 		|| strcmp (ASM_OPERANDS_INPUT_CONSTRAINT (x, i),
! 			   ASM_OPERANDS_INPUT_CONSTRAINT (y, i)))
! 	      return 0;
! 	}
! 
!       return 1;
! 
!     default:
!       break;
!     }
! 
!   /* Compare the elements.  If any pair of corresponding elements
!      fail to match, return 0 for the whole thing.  */
! 
!   fmt = GET_RTX_FORMAT (code);
!   for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
!     {
!       switch (fmt[i])
! 	{
! 	case 'e':
! 	  if (! expr_equiv_p (XEXP (x, i), XEXP (y, i)))
! 	    return 0;
! 	  break;
! 
! 	case 'E':
! 	  if (XVECLEN (x, i) != XVECLEN (y, i))
! 	    return 0;
! 	  for (j = 0; j < XVECLEN (x, i); j++)
! 	    if (! expr_equiv_p (XVECEXP (x, i, j), XVECEXP (y, i, j)))
! 	      return 0;
! 	  break;
! 
! 	case 's':
! 	  if (strcmp (XSTR (x, i), XSTR (y, i)))
! 	    return 0;
! 	  break;
! 
! 	case 'i':
! 	  if (XINT (x, i) != XINT (y, i))
! 	    return 0;
! 	  break;
! 
! 	case 'w':
! 	  if (XWINT (x, i) != XWINT (y, i))
! 	    return 0;
! 	break;
! 
! 	case '0':
! 	  break;
! 
! 	default:
! 	  abort ();
! 	}
!     }
! 
!   return 1;
  }
  
  /* Insert expression X in INSN in the hash TABLE.
--- 1491,1502 ----
    return hash % hash_table_size;
  }
  
! /* Return nonzero if exp1 is equivalent to exp2.  */
  
  static int
  expr_equiv_p (rtx x, rtx y)
  {
!   return exp_equiv_p (x, y, 0, true);
  }
  
  /* Insert expression X in INSN in the hash TABLE.
*************** compute_hash_table (struct hash_table *t
*** 2556,2583 ****
  
  /* Expression tracking support.  */
  
- /* Lookup pattern PAT in the expression TABLE.
-    The result is a pointer to the table entry, or NULL if not found.  */
- 
- static struct expr *
- lookup_expr (rtx pat, struct hash_table *table)
- {
-   int do_not_record_p;
-   unsigned int hash = hash_expr (pat, GET_MODE (pat), &do_not_record_p,
- 				 table->size);
-   struct expr *expr;
- 
-   if (do_not_record_p)
-     return NULL;
- 
-   expr = table->table[hash];
- 
-   while (expr && ! expr_equiv_p (expr->expr, pat))
-     expr = expr->next_same_hash;
- 
-   return expr;
- }
- 
  /* Lookup REGNO in the set TABLE.  The result is a pointer to the
     table entry, or NULL if not found.  */
  
--- 2219,2224 ----
*************** ldst_entry (rtx x)
*** 5426,5432 ****
    struct ls_expr * ptr;
    unsigned int hash;
  
!   hash = hash_expr_1 (x, GET_MODE (x), & do_not_record_p);
  
    for (ptr = pre_ldst_mems; ptr != NULL; ptr = ptr->next)
      if (ptr->hash_index == hash && expr_equiv_p (ptr->pattern, x))
--- 5067,5074 ----
    struct ls_expr * ptr;
    unsigned int hash;
  
!   hash = hash_rtx (x, GET_MODE (x), &do_not_record_p,
! 		   NULL,  /*have_reg_qty=*/false);
  
    for (ptr = pre_ldst_mems; ptr != NULL; ptr = ptr->next)
      if (ptr->hash_index == hash && expr_equiv_p (ptr->pattern, x))
*************** is_too_expensive (const char *pass)
*** 6945,7598 ****
    return false;
  }
  
- /* The following code implements gcse after reload, the purpose of this
-    pass is to cleanup redundant loads generated by reload and other
-    optimizations that come after gcse. It searches for simple inter-block
-    redundancies and tries to eliminate them by adding moves and loads
-    in cold places.  */
- 
- /* The following structure holds the information about the occurrences of
-    the redundant instructions.  */
- struct unoccr
- {
-   struct unoccr *next;
-   edge pred;
-   rtx insn;
- };
- 
- static bool reg_used_on_edge (rtx, edge);
- static rtx reg_set_between_after_reload_p (rtx, rtx, rtx);
- static rtx reg_used_between_after_reload_p (rtx, rtx, rtx);
- static rtx get_avail_load_store_reg (rtx);
- static bool is_jump_table_basic_block (basic_block);
- static bool bb_has_well_behaved_predecessors (basic_block);
- static struct occr* get_bb_avail_insn (basic_block, struct occr *);
- static void hash_scan_set_after_reload (rtx, rtx, struct hash_table *);
- static void compute_hash_table_after_reload (struct hash_table *);
- static void eliminate_partially_redundant_loads (basic_block,
- 						rtx,
- 						struct expr *);
- static void gcse_after_reload (void);
- static struct occr* get_bb_avail_insn (basic_block, struct occr *);
- void gcse_after_reload_main (rtx, FILE *);
- 
- 
- /* Check if register REG is used in any insn waiting to be inserted on E.
-    Assumes no such insn can be a CALL_INSN; if so call reg_used_between_p
-    with PREV(insn),NEXT(insn) instead of calling
-    reg_overlap_mentioned_p.  */
- 
- static bool
- reg_used_on_edge (rtx reg, edge e)
- {
-   rtx insn;
- 
-   for (insn = e->insns.r; insn; insn = NEXT_INSN (insn))
-     if (INSN_P (insn) && reg_overlap_mentioned_p (reg, PATTERN (insn)))
-       return true;
- 
-   return false;
- }
- 
- /* Return the insn that sets register REG or clobbers it in between
-    FROM_INSN and TO_INSN (exclusive of those two).
-    Just like reg_set_between but for hard registers and not pseudos.  */
- 
- static rtx
- reg_set_between_after_reload_p (rtx reg, rtx from_insn, rtx to_insn)
- {
-   rtx insn;
-   int regno;
- 
-   if (! REG_P (reg))
-     abort ();
-   regno = REGNO (reg);
- 
-   /* We are called after register allocation.  */
-   if (regno >= FIRST_PSEUDO_REGISTER)
-     abort ();
- 
-   if (from_insn == to_insn)
-     return NULL_RTX;
- 
-   for (insn = NEXT_INSN (from_insn);
-        insn != to_insn;
-        insn = NEXT_INSN (insn))
-     {
-       if (INSN_P (insn))
- 	{
- 	  if (FIND_REG_INC_NOTE (insn, reg)
- 	      || (CALL_P (insn)
- 		  && call_used_regs[regno])
- 	      || find_reg_fusage (insn, CLOBBER, reg))
- 	    return insn;
- 	}
-       if (set_of (reg, insn) != NULL_RTX)
- 	return insn;
-     }
-   return NULL_RTX;
- }
- 
- /* Return the insn that uses register REG in between FROM_INSN and TO_INSN
-    (exclusive of those two). Similar to reg_used_between but for hard
-    registers and not pseudos.  */
- 
- static rtx
- reg_used_between_after_reload_p (rtx reg, rtx from_insn, rtx to_insn)
- {
-   rtx insn;
-   int regno;
- 
-   if (! REG_P (reg))
-     return to_insn;
-   regno = REGNO (reg);
- 
-   /* We are called after register allocation.  */
-   if (regno >= FIRST_PSEUDO_REGISTER)
-     abort ();
-   if (from_insn == to_insn)
-     return NULL_RTX;
- 
-   for (insn = NEXT_INSN (from_insn);
-        insn != to_insn;
-        insn = NEXT_INSN (insn))
-     if (INSN_P (insn)
- 	&& (reg_overlap_mentioned_p (reg, PATTERN (insn))
- 	    || (CALL_P (insn)
- 		&& call_used_regs[regno])
- 	    || find_reg_fusage (insn, USE, reg)
- 	    || find_reg_fusage (insn, CLOBBER, reg)))
-       return insn;
-   return NULL_RTX;
- }
- 
- /* Return the loaded/stored register of a load/store instruction.  */
- 
- static rtx
- get_avail_load_store_reg (rtx insn)
- {
-   if (REG_P (SET_DEST (PATTERN (insn))))  /* A load.  */
-     return SET_DEST(PATTERN(insn));
-   if (REG_P (SET_SRC (PATTERN (insn))))  /* A store.  */
-     return SET_SRC (PATTERN (insn));
-   abort ();
- }
- 
- /* Don't handle ABNORMAL edges or jump tables.  */
- 
- static bool
- is_jump_table_basic_block (basic_block bb)
- {
-   rtx insn = BB_END (bb);
- 
-   if (JUMP_TABLE_DATA_P (insn))
-     return true;
-   return false;
- }
- 
- /* Return nonzero if the predecessors of BB are "well behaved".  */
- 
- static bool
- bb_has_well_behaved_predecessors (basic_block bb)
- {
-   edge pred;
- 
-   if (! bb->pred)
-     return false;
-   for (pred = bb->pred; pred != NULL; pred = pred->pred_next)
-     if (((pred->flags & EDGE_ABNORMAL) && EDGE_CRITICAL_P (pred))
- 	|| is_jump_table_basic_block (pred->src))
-       return false;
-   return true;
- }
- 
- 
- /* Search for the occurrences of expression in BB.  */
- 
- static struct occr*
- get_bb_avail_insn (basic_block bb, struct occr *occr)
- {
-   for (; occr != NULL; occr = occr->next)
-     if (BLOCK_FOR_INSN (occr->insn)->index == bb->index)
-       return occr;
-   return NULL;
- }
- 
- /* Perform partial GCSE pass after reload, try to eliminate redundant loads
-    created by the reload pass. We try to look for a full or partial
-    redundant loads fed by one or more loads/stores in predecessor BBs,
-    and try adding loads to make them fully redundant. We also check if
-    it's worth adding loads to be able to delete the redundant load.
- 
-    Algorithm:
-    1. Build available expressions hash table:
-        For each load/store instruction, if the loaded/stored memory didn't
-        change until the end of the basic block add this memory expression to
-        the hash table.
-    2. Perform Redundancy elimination:
-       For each load instruction do the following:
- 	 perform partial redundancy elimination, check if it's worth adding
- 	 loads to make the load fully redundant. If so add loads and
- 	 register copies and delete the load.
- 
-    Future enhancement:
-      if loaded register is used/defined between load and some store,
-      look for some other free register between load and all its stores,
-      and replace load with a copy from this register to the loaded
-      register.  */
- 
- 
- /* This handles the case where several stores feed a partially redundant
-    load. It checks if the redundancy elimination is possible and if it's
-    worth it.  */
- 
- static void
- eliminate_partially_redundant_loads (basic_block bb, rtx insn,
- 				     struct expr *expr)
- {
-   edge pred;
-   rtx avail_insn = NULL_RTX;
-   rtx avail_reg;
-   rtx dest, pat;
-   struct occr *a_occr;
-   struct unoccr *occr, *avail_occrs = NULL;
-   struct unoccr *unoccr, *unavail_occrs = NULL;
-   int npred_ok = 0;
-   gcov_type ok_count = 0; /* Redundant load execution count.  */
-   gcov_type critical_count = 0; /* Execution count of critical edges.  */
- 
-   /* The execution count of the loads to be added to make the
-      load fully redundant.  */
-   gcov_type not_ok_count = 0;
-   basic_block pred_bb;
- 
-   pat = PATTERN (insn);
-   dest = SET_DEST (pat);
-   /* Check that the loaded register is not used, set, or killed from the
-      beginning of the block.  */
-   if (reg_used_between_after_reload_p (dest,
-                                        PREV_INSN (BB_HEAD (bb)), insn)
-       || reg_set_between_after_reload_p (dest,
-                                          PREV_INSN (BB_HEAD (bb)), insn))
-     return;
- 
-   /* Check potential for replacing load with copy for predecessors.  */
-   for (pred = bb->pred; pred; pred = pred->pred_next)
-     {
-       rtx next_pred_bb_end;
- 
-       avail_insn = NULL_RTX;
-       pred_bb = pred->src;
-       next_pred_bb_end = NEXT_INSN (BB_END (pred_bb));
-       for (a_occr = get_bb_avail_insn (pred_bb, expr->avail_occr); a_occr;
- 	   a_occr = get_bb_avail_insn (pred_bb, a_occr->next))
- 	{
- 	  /* Check if the loaded register is not used.  */
- 	  avail_insn = a_occr->insn;
- 	  if (! (avail_reg = get_avail_load_store_reg (avail_insn)))
- 	    abort ();
- 	  /* Make sure we can generate a move from register avail_reg to
- 	     dest.  */
- 	  extract_insn (gen_move_insn (copy_rtx (dest),
- 				       copy_rtx (avail_reg)));
- 	  if (! constrain_operands (1)
- 	      || reg_killed_on_edge (avail_reg, pred)
- 	      || reg_used_on_edge (dest, pred))
- 	    {
- 	      avail_insn = NULL;
- 	      continue;
- 	    }
- 	  if (! reg_set_between_after_reload_p (avail_reg, avail_insn,
- 						next_pred_bb_end))
- 	    /* AVAIL_INSN remains non-null.  */
- 	    break;
- 	  else
- 	    avail_insn = NULL;
- 	}
-       if (avail_insn != NULL_RTX)
- 	{
- 	  npred_ok++;
- 	  ok_count += pred->count;
-           if (EDGE_CRITICAL_P (pred))
-             critical_count += pred->count;
- 	  occr = gmalloc (sizeof (struct unoccr));
- 	  occr->insn = avail_insn;
- 	  occr->pred = pred;
- 	  occr->next = avail_occrs;
- 	  avail_occrs = occr;
- 	}
-       else
- 	{
- 	  not_ok_count += pred->count;
-           if (EDGE_CRITICAL_P (pred))
-             critical_count += pred->count;
- 	  unoccr = gmalloc (sizeof (struct unoccr));
- 	  unoccr->insn = NULL_RTX;
- 	  unoccr->pred = pred;
- 	  unoccr->next = unavail_occrs;
- 	  unavail_occrs = unoccr;
- 	}
-     }
- 
-   if (npred_ok == 0    /* No load can be replaced by copy.  */
-       || (optimize_size && npred_ok > 1)) /* Prevent exploding the code.  */
-     goto cleanup;
- 
-   /* Check if it's worth applying the partial redundancy elimination.  */
-   if (ok_count < GCSE_AFTER_RELOAD_PARTIAL_FRACTION * not_ok_count)
-     goto cleanup;
- 
-   if (ok_count < GCSE_AFTER_RELOAD_CRITICAL_FRACTION * critical_count)
-     goto cleanup;
- 
-   /* Generate moves to the loaded register from where
-      the memory is available.  */
-   for (occr = avail_occrs; occr; occr = occr->next)
-     {
-       avail_insn = occr->insn;
-       pred = occr->pred;
-       /* Set avail_reg to be the register having the value of the
- 	 memory.  */
-       avail_reg = get_avail_load_store_reg (avail_insn);
-       if (! avail_reg)
- 	abort ();
- 
-       insert_insn_on_edge (gen_move_insn (copy_rtx (dest),
- 					  copy_rtx (avail_reg)),
- 			   pred);
- 
-       if (gcse_file)
- 	fprintf (gcse_file,
- 		 "GCSE AFTER reload generating move from %d to %d on \
- 		 edge from %d to %d\n",
- 		 REGNO (avail_reg),
- 		 REGNO (dest),
- 		 pred->src->index,
- 		 pred->dest->index);
-     }
- 
-   /* Regenerate loads where the memory is unavailable.  */
-   for (unoccr = unavail_occrs; unoccr; unoccr = unoccr->next)
-     {
-       pred = unoccr->pred;
-       insert_insn_on_edge (copy_insn (PATTERN (insn)), pred);
- 
-       if (gcse_file)
- 	fprintf (gcse_file,
- 		 "GCSE AFTER reload: generating on edge from %d to %d\
- 		  a copy of load:\n",
- 		 pred->src->index,
- 		 pred->dest->index);
-     }
- 
-   /* Delete the insn if it is not available in this block and mark it
-      for deletion if it is available. If insn is available it may help
-      discover additional redundancies, so mark it for later deletion.*/
-   for (a_occr = get_bb_avail_insn (bb, expr->avail_occr);
-        a_occr && (a_occr->insn != insn);
-        a_occr = get_bb_avail_insn (bb, a_occr->next));
- 
-   if (!a_occr)
-     delete_insn (insn);
-   else
-     a_occr->deleted_p = 1;
- 
- cleanup:
- 
-   while (unavail_occrs)
-     {
-       struct unoccr *temp = unavail_occrs->next;
-       free (unavail_occrs);
-       unavail_occrs = temp;
-     }
- 
-   while (avail_occrs)
-     {
-       struct unoccr *temp = avail_occrs->next;
-       free (avail_occrs);
-       avail_occrs = temp;
-     }
- }
- 
- /* Performing the redundancy elimination as described before.  */
- 
- static void
- gcse_after_reload (void)
- {
-   unsigned int i;
-   rtx insn;
-   basic_block bb;
-   struct expr *expr;
-   struct occr *occr;
- 
-   /* Note we start at block 1.  */
- 
-   if (ENTRY_BLOCK_PTR->next_bb == EXIT_BLOCK_PTR)
-     return;
- 
-   FOR_BB_BETWEEN (bb,
- 		  ENTRY_BLOCK_PTR->next_bb->next_bb,
- 		  EXIT_BLOCK_PTR,
- 		  next_bb)
-     {
-       if (! bb_has_well_behaved_predecessors (bb))
- 	continue;
- 
-       /* Do not try this optimization on cold basic blocks.  */
-       if (probably_cold_bb_p (bb))
- 	continue;
- 
-       reset_opr_set_tables ();
- 
-       for (insn = BB_HEAD (bb);
- 	   insn != NULL
- 	   && insn != NEXT_INSN (BB_END (bb));
- 	   insn = NEXT_INSN (insn))
- 	{
- 	  /* Is it a load - of the form (set (reg) (mem))?  */
- 	  if (NONJUMP_INSN_P (insn)
-               && GET_CODE (PATTERN (insn)) == SET
- 	      && REG_P (SET_DEST (PATTERN (insn)))
- 	      && MEM_P (SET_SRC (PATTERN (insn))))
- 	    {
- 	      rtx pat = PATTERN (insn);
- 	      rtx src = SET_SRC (pat);
- 	      struct expr *expr;
- 
- 	      if (general_operand (src, GET_MODE (src))
- 		  /* Is the expression recorded?  */
- 		  && (expr = lookup_expr (src, &expr_hash_table)) != NULL
- 		  /* Are the operands unchanged since the start of the
- 		     block?  */
- 		  && oprs_not_set_p (src, insn)
- 		  && ! MEM_VOLATILE_P (src)
- 		  && GET_MODE (src) != BLKmode
- 		  && !(flag_non_call_exceptions && may_trap_p (src))
- 		  && !side_effects_p (src))
- 		{
- 		  /* We now have a load (insn) and an available memory at
- 		     its BB start (expr). Try to remove the loads if it is
- 		     redundant.  */
- 		  eliminate_partially_redundant_loads (bb, insn, expr);
- 		}
- 	    }
- 
- 	    /* Keep track of everything modified by this insn.  */
- 	    if (INSN_P (insn))
- 	      mark_oprs_set (insn);
- 	}
-     }
- 
-   commit_edge_insertions ();
- 
-   /* Go over the expression hash table and delete insns that were
-      marked for later deletion.  */
-   for (i = 0; i < expr_hash_table.size; i++)
-     {
-       for (expr = expr_hash_table.table[i];
- 	   expr != NULL;
- 	   expr = expr->next_same_hash)
- 	for (occr = expr->avail_occr; occr; occr = occr->next)
- 	  if (occr->deleted_p)
- 	    delete_insn (occr->insn);
-     }
- }
- 
- /* Scan pattern PAT of INSN and add an entry to the hash TABLE.
-    After reload we are interested in loads/stores only.  */
- 
- static void
- hash_scan_set_after_reload (rtx pat, rtx insn, struct hash_table *table)
- {
-   rtx src = SET_SRC (pat);
-   rtx dest = SET_DEST (pat);
- 
-   if (! MEM_P (src) && ! MEM_P (dest))
-     return;
- 
-   if (REG_P (dest))
-     {
-       if (/* Don't GCSE something if we can't do a reg/reg copy.  */
- 	  can_copy_p (GET_MODE (dest))
- 	  /* GCSE commonly inserts instruction after the insn.  We can't
- 	     do that easily for EH_REGION notes so disable GCSE on these
- 	     for now.  */
- 	  && ! find_reg_note (insn, REG_EH_REGION, NULL_RTX)
- 	  /* Is SET_SRC something we want to gcse?  */
- 	  && general_operand (src, GET_MODE (src))
- 	  /* Don't CSE a nop.  */
- 	  && ! set_noop_p (pat)
- 	  && ! JUMP_P (insn))
- 	{
- 	  /* An expression is not available if its operands are
- 	     subsequently modified, including this insn.  */
- 	  if (oprs_available_p (src, insn))
- 	    insert_expr_in_table (src, GET_MODE (dest), insn, 0, 1, table);
- 	}
-     }
-   else if (REG_P (src))
-     {
-       /* Only record sets of pseudo-regs in the hash table.  */
-       if (/* Don't GCSE something if we can't do a reg/reg copy.  */
- 	  can_copy_p (GET_MODE (src))
- 	  /* GCSE commonly inserts instruction after the insn.  We can't
- 	     do that easily for EH_REGION notes so disable GCSE on these
- 	     for now.  */
- 	  && ! find_reg_note (insn, REG_EH_REGION, NULL_RTX)
- 	  /* Is SET_DEST something we want to gcse?  */
- 	  && general_operand (dest, GET_MODE (dest))
- 	  /* Don't CSE a nop.  */
- 	  && ! set_noop_p (pat)
- 	  &&! JUMP_P (insn)
- 	  && ! (flag_float_store && FLOAT_MODE_P (GET_MODE (dest)))
- 	  /* Check if the memory expression is killed after insn.  */
- 	  && ! load_killed_in_block_p (BLOCK_FOR_INSN (insn),
- 				       INSN_CUID (insn) + 1,
- 				       dest,
- 				       1)
- 	  && oprs_unchanged_p (XEXP (dest, 0), insn, 1))
- 	{
- 	  insert_expr_in_table (dest, GET_MODE (dest), insn, 0, 1, table);
- 	}
-     }
- }
- 
- 
- /* Create hash table of memory expressions available at end of basic
-    blocks.  */
- 
- static void
- compute_hash_table_after_reload (struct hash_table *table)
- {
-   unsigned int i;
- 
-   table->set_p = 0;
- 
-   /* Initialize count of number of entries in hash table.  */
-   table->n_elems = 0;
-   memset ((char *) table->table, 0,
- 	  table->size * sizeof (struct expr *));
- 
-   /* While we compute the hash table we also compute a bit array of which
-      registers are set in which blocks.  */
-   sbitmap_vector_zero (reg_set_in_block, last_basic_block);
- 
-   /* Re-cache any INSN_LIST nodes we have allocated.  */
-   clear_modify_mem_tables ();
- 
-   /* Some working arrays used to track first and last set in each block.  */
-   reg_avail_info = gmalloc (max_gcse_regno * sizeof (struct reg_avail_info));
- 
-   for (i = 0; i < max_gcse_regno; ++i)
-     reg_avail_info[i].last_bb = NULL;
- 
-   FOR_EACH_BB (current_bb)
-     {
-       rtx insn;
-       unsigned int regno;
- 
-       /* First pass over the instructions records information used to
- 	 determine when registers and memory are first and last set.  */
-       for (insn = BB_HEAD (current_bb);
- 	   insn && insn != NEXT_INSN (BB_END (current_bb));
- 	   insn = NEXT_INSN (insn))
- 	{
- 	  if (! INSN_P (insn))
- 	    continue;
- 
- 	  if (CALL_P (insn))
- 	    {
- 	      bool clobbers_all = false;
- 
- #ifdef NON_SAVING_SETJMP
- 	      if (NON_SAVING_SETJMP
- 		  && find_reg_note (insn, REG_SETJMP, NULL_RTX))
- 		clobbers_all = true;
- #endif
- 
- 	      for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
- 		if (clobbers_all
- 		    || TEST_HARD_REG_BIT (regs_invalidated_by_call,
- 					  regno))
- 		  record_last_reg_set_info (insn, regno);
- 
- 	      mark_call (insn);
- 	    }
- 
- 	    note_stores (PATTERN (insn), record_last_set_info, insn);
- 
- 	    if (GET_CODE (PATTERN (insn)) == SET)
- 	      {
- 		rtx src, dest;
- 
- 		src = SET_SRC (PATTERN (insn));
- 		dest = SET_DEST (PATTERN (insn));
- 		if (MEM_P (src) && auto_inc_p (XEXP (src, 0)))
- 		  {
- 		    regno = REGNO (XEXP (XEXP (src, 0), 0));
- 		    record_last_reg_set_info (insn, regno);
- 		  }
- 		if (MEM_P (dest) && auto_inc_p (XEXP (dest, 0)))
- 		  {
- 		    regno = REGNO (XEXP (XEXP (dest, 0), 0));
- 		    record_last_reg_set_info (insn, regno);
- 		  }
- 		}
- 	  }
- 
- 	/* The next pass builds the hash table.  */
- 	for (insn = BB_HEAD (current_bb);
- 	     insn && insn != NEXT_INSN (BB_END (current_bb));
- 	     insn = NEXT_INSN (insn))
- 	  if (INSN_P (insn) && GET_CODE (PATTERN (insn)) == SET)
- 	    if (! find_reg_note (insn, REG_LIBCALL, NULL_RTX))
- 	      hash_scan_set_after_reload (PATTERN (insn), insn, table);
-     }
- 
-   free (reg_avail_info);
-   reg_avail_info = NULL;
- }
- 
- 
- /* Main entry point of the GCSE after reload - clean some redundant loads
-    due to spilling.  */
- 
- void
- gcse_after_reload_main (rtx f, FILE* file)
- {
-   gcse_subst_count = 0;
-   gcse_create_count = 0;
- 
-   gcse_file = file;
- 
-   gcc_obstack_init (&gcse_obstack);
-   bytes_used = 0;
- 
-   /* We need alias.  */
-   init_alias_analysis ();
- 
-   max_gcse_regno = max_reg_num ();
- 
-   alloc_reg_set_mem (max_gcse_regno);
-   alloc_gcse_mem (f);
-   alloc_hash_table (max_cuid, &expr_hash_table, 0);
-   compute_hash_table_after_reload (&expr_hash_table);
- 
-   if (gcse_file)
-     dump_hash_table (gcse_file, "Expression", &expr_hash_table);
- 
-   if (expr_hash_table.n_elems > 0)
-     gcse_after_reload ();
- 
-   free_hash_table (&expr_hash_table);
- 
-   free_gcse_mem ();
-   free_reg_set_mem ();
- 
-   /* We are finished with alias.  */
-   end_alias_analysis ();
- 
-   obstack_free (&gcse_obstack, NULL);
- }
- 
  #include "gt-gcse.h"
--- 6587,6590 ----
Index: passes.c
===================================================================
RCS file: /cvs/gcc/gcc/gcc/passes.c,v
retrieving revision 2.36
diff -c -3 -p -r2.36 passes.c
*** passes.c	5 Aug 2004 05:51:50 -0000	2.36
--- passes.c	18 Aug 2004 17:51:30 -0000
*************** rest_of_handle_sched2 (void)
*** 839,848 ****
  static void
  rest_of_handle_gcse2 (void)
  {
!   timevar_push (TV_RELOAD_CSE_REGS);
    open_dump_file (DFI_gcse2, current_function_decl);
  
!   gcse_after_reload_main (get_insns (), dump_file);
    rebuild_jump_labels (get_insns ());
    delete_trivially_dead_insns (get_insns (), max_reg_num ());
    close_dump_file (DFI_gcse2, print_rtl_with_bb, get_insns ());
--- 839,848 ----
  static void
  rest_of_handle_gcse2 (void)
  {
!   timevar_push (TV_GCSE_AFTER_RELOAD);
    open_dump_file (DFI_gcse2, current_function_decl);
  
!   gcse_after_reload_main (get_insns ());
    rebuild_jump_labels (get_insns ());
    delete_trivially_dead_insns (get_insns (), max_reg_num ());
    close_dump_file (DFI_gcse2, print_rtl_with_bb, get_insns ());
*************** rest_of_handle_gcse2 (void)
*** 853,859 ****
    verify_flow_info ();
  #endif
  
!   timevar_pop (TV_RELOAD_CSE_REGS);
  }
  
  /* Register allocation pre-pass, to reduce number of moves necessary
--- 853,859 ----
    verify_flow_info ();
  #endif
  
!   timevar_pop (TV_GCSE_AFTER_RELOAD);
  }
  
  /* Register allocation pre-pass, to reduce number of moves necessary
Index: postreload-gcse.c
===================================================================
RCS file: postreload-gcse.c
diff -N postreload-gcse.c
*** /dev/null	1 Jan 1970 00:00:00 -0000
--- postreload-gcse.c	18 Aug 2004 17:51:30 -0000
***************
*** 0 ****
--- 1,1379 ----
+ /* Post reload partially redundant load elimination
+    Copyright (C) 2004
+    Free Software Foundation, Inc.
+ 
+ This file is part of GCC.
+ 
+ GCC 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.
+ 
+ GCC 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 GCC; see the file COPYING.  If not, write to the Free
+ Software Foundation, 59 Temple Place - Suite 330, Boston, MA
+ 02111-1307, USA.  */
+ 
+ #include "config.h"
+ #include "system.h"
+ #include "coretypes.h"
+ #include "tm.h"
+ #include "toplev.h"
+ 
+ #include "rtl.h"
+ #include "tree.h"
+ #include "tm_p.h"
+ #include "regs.h"
+ #include "hard-reg-set.h"
+ #include "flags.h"
+ #include "real.h"
+ #include "insn-config.h"
+ #include "recog.h"
+ #include "basic-block.h"
+ #include "output.h"
+ #include "function.h"
+ #include "expr.h"
+ #include "except.h"
+ #include "intl.h"
+ #include "obstack.h"
+ #include "hashtab.h"
+ #include "params.h"
+ 
+ /* The following code implements gcse after reload, the purpose of this
+    pass is to cleanup redundant loads generated by reload and other
+    optimizations that come after gcse. It searches for simple inter-block
+    redundancies and tries to eliminate them by adding moves and loads
+    in cold places.
+ 
+    Perform partially redundant load elimination, try to eliminate redundant
+    loads created by the reload pass.  We try to look for full or partial
+    redundant loads fed by one or more loads/stores in predecessor BBs,
+    and try adding loads to make them fully redundant.  We also check if
+    it's worth adding loads to be able to delete the redundant load.
+ 
+    Algorithm:
+    1. Build available expressions hash table:
+        For each load/store instruction, if the loaded/stored memory didn't
+        change until the end of the basic block add this memory expression to
+        the hash table.
+    2. Perform Redundancy elimination:
+       For each load instruction do the following:
+ 	 perform partial redundancy elimination, check if it's worth adding
+ 	 loads to make the load fully redundant.  If so add loads and
+ 	 register copies and delete the load.
+    3. Delete instructions made redundant in step 2.
+ 
+    Future enhancement:
+      If the loaded register is used/defined between load and some store,
+      look for some other free register between load and all its stores,
+      and replace the load with a copy from this register to the loaded
+      register.
+ */
+ 
+ 
+ /* Keep statistics of this pass.  */
+ static struct
+ {
+   int moves_inserted;
+   int copies_inserted;
+   int insns_deleted;
+ } stats;
+ 
+ /* We need to keep a hash table of expressions.  The table entries are of
+    type 'struct expr', and for each expression there is a single linked
+    list of occurences.  */
+ 
+ /* The table itself.  */
+ static htab_t expr_table;
+ 
+ /* Expression elements in the hash table.  */
+ struct expr
+ {
+   /* The expression (SET_SRC for expressions, PATTERN for assignments).  */
+   rtx expr;
+ 
+   /* The same hash for this entry.  */
+   hashval_t hash;
+ 
+   /* List of available occurrence in basic blocks in the function.  */
+   struct occr *avail_occr;
+ };
+ 
+ static struct obstack expr_obstack;
+ 
+ /* Occurrence of an expression.
+    There is at most one occurence per basic block.  If a pattern appears
+    more than once, the last appearance is used.  */
+ 
+ struct occr
+ {
+   /* Next occurrence of this expression.  */
+   struct occr *next;
+   /* The insn that computes the expression.  */
+   rtx insn;
+   /* Nonzero if this [anticipatable] occurrence has been deleted.  */
+   char deleted_p;
+ };
+ 
+ static struct obstack occr_obstack;
+ 
+ /* The following structure holds the information about the occurrences of
+    the redundant instructions.  */
+ struct unoccr
+ {
+   struct unoccr *next;
+   edge pred;
+   rtx insn;
+ };
+ 
+ static struct obstack unoccr_obstack;
+ 
+ /* Array where each element is the CUID if the insn that last set the hard
+    register with the number of the element, since the start of the current
+    basic block.  */
+ static int *reg_avail_info;
+ 
+ /* A list of insns that may modify memory within the current basic block.  */
+ struct modifies_mem
+ {
+   rtx insn;
+   struct modifies_mem *next;
+ };
+ static struct modifies_mem *modifies_mem_list;
+ 
+ /* The modifies_mem structs also go on an obstack, only this obstack is
+    freed each time after completing the analysis or transformations on
+    a basic block.  So we allocate a dummy modifies_mem_obstack_bottom
+    object on the obstack to keep track of the bottom of the obstack.  */
+ static struct obstack modifies_mem_obstack;
+ static struct modifies_mem  *modifies_mem_obstack_bottom;
+ 
+ /* Mapping of insn UIDs to CUIDs.
+    CUIDs are like UIDs except they increase monotonically in each basic
+    block, have no gaps, and only apply to real insns.  */
+ static int *uid_cuid;
+ #define INSN_CUID(INSN) (uid_cuid[INSN_UID (INSN)])
+ 
+ 
+ /* Helpers for memory allocation/freeing.  */
+ static void alloc_mem (void);
+ static void free_mem (void);
+ 
+ /* Support for hash table construction and transformations.  */
+ static bool oprs_unchanged_p (rtx, rtx, bool);
+ static void record_last_reg_set_info (rtx, int);
+ static void record_last_mem_set_info (rtx);
+ static void record_last_set_info (rtx, rtx, void *);
+ static void mark_call (rtx);
+ static void mark_set (rtx, rtx);
+ static void mark_clobber (rtx, rtx);
+ static void mark_oprs_set (rtx);
+ 
+ static void find_mem_conflicts (rtx, rtx, void *);
+ static int load_killed_in_block_p (int, rtx, bool);
+ static void reset_opr_set_tables (void);
+ 
+ /* Hash table support.  */
+ static hashval_t hash_expr (rtx, int *);
+ static hashval_t hash_expr_for_htab (const void *);
+ static int expr_equiv_p (const void *, const void *);
+ static void insert_expr_in_table (rtx, rtx);
+ static struct expr *lookup_expr_in_table (rtx);
+ static int dump_hash_table_entry (void **, void *);
+ static void dump_hash_table (FILE *);
+ 
+ /* Helpers for eliminate_partially_redundant_load.  */
+ static bool reg_killed_on_edge (rtx, edge);
+ static bool reg_used_on_edge (rtx, edge);
+ 
+ static rtx reg_set_between_after_reload_p (rtx, rtx, rtx);
+ static rtx reg_used_between_after_reload_p (rtx, rtx, rtx);
+ static rtx get_avail_load_store_reg (rtx);
+ 
+ static bool bb_has_well_behaved_predecessors (basic_block);
+ static struct occr* get_bb_avail_insn (basic_block, struct occr *);
+ static void hash_scan_set (rtx);
+ static void compute_hash_table (void);
+ 
+ /* The work horses of this pass.  */
+ static void eliminate_partially_redundant_load (basic_block,
+ 						rtx,
+ 						struct expr *);
+ static void eliminate_partially_redundant_loads (void);
+ 
+ 
+ /* Allocate memory for the CUID mapping array and register/memory
+    tracking tables.  */
+ 
+ static void
+ alloc_mem (void)
+ {
+   int i;
+   basic_block bb;
+   rtx insn;
+ 
+   /* Find the largest UID and create a mapping from UIDs to CUIDs.  */
+   uid_cuid = xcalloc (get_max_uid () + 1, sizeof (int));
+   i = 0;
+   FOR_EACH_BB (bb)
+     FOR_BB_INSNS (bb, insn)
+       {
+         if (INSN_P (insn))
+ 	  uid_cuid[INSN_UID (insn)] = i++;
+ 	else
+ 	  uid_cuid[INSN_UID (insn)] = i;
+       }
+ 
+   /* Allocate the available expressions hash table.  We don't want to
+      make the hash table too small, but unnecessarily making it too large
+      also doesn't help.  The i/4 is a gcse.c relic, and seems like a
+      reasonable choice.  */
+   expr_table = htab_create (MAX (i / 4, 13),
+ 			    hash_expr_for_htab, expr_equiv_p, NULL);
+ 
+   /* We allocate everything on obstacks because we often can roll back
+      the whole obstack to some point.  Freeing obstacks is very fast.  */
+   gcc_obstack_init (&expr_obstack);
+   gcc_obstack_init (&occr_obstack);
+   gcc_obstack_init (&unoccr_obstack);
+   gcc_obstack_init (&modifies_mem_obstack);
+ 
+   /* Working array used to track the last set for each register
+      in the current block.  */
+   reg_avail_info = (int *) xmalloc (FIRST_PSEUDO_REGISTER * sizeof (int));
+ 
+   /* Put a dummy modifies_mem object on the modifies_mem_obstack, so we
+      can roll it back in reset_opr_set_tables.  */
+   modifies_mem_obstack_bottom =
+     (struct modifies_mem *) obstack_alloc (&modifies_mem_obstack,
+ 					   sizeof (struct modifies_mem));
+ }
+ 
+ /* Free memory allocated by alloc_mem.  */
+ 
+ static void
+ free_mem (void)
+ {
+   free (uid_cuid);
+ 
+   htab_delete (expr_table);
+ 
+   obstack_free (&expr_obstack, NULL);
+   obstack_free (&occr_obstack, NULL);
+   obstack_free (&unoccr_obstack, NULL);
+   obstack_free (&modifies_mem_obstack, NULL);
+ 
+   free (reg_avail_info);
+ }
+ 
+ 
+ /* Hash expression X.
+    DO_NOT_RECORD_P is a boolean indicating if a volatile operand is found
+    or if the expression contains something we don't want to insert in the
+    table.  */
+ 
+ static hashval_t
+ hash_expr (rtx x, int *do_not_record_p)
+ {
+   *do_not_record_p = 0;
+   return hash_rtx (x, GET_MODE (x), do_not_record_p,
+ 		   NULL,  /*have_reg_qty=*/false);
+ }
+ 
+ /* Callback for hashtab.
+    Return the hash value for expression EXP.  We don't actually hash
+    here, we just return the cached hash value.  */
+ 
+ static hashval_t
+ hash_expr_for_htab (const void *expp)
+ {
+   struct expr *exp = (struct expr *) expp;
+   return exp->hash;
+ }
+ 
+ /* Callbach for hashtab.
+    Return nonzero if exp1 is equivalent to exp2.  */
+ 
+ static int
+ expr_equiv_p (const void *exp1p, const void *exp2p)
+ {
+   struct expr *exp1 = (struct expr *) exp1p;
+   struct expr *exp2 = (struct expr *) exp2p;
+   int equiv_p = exp_equiv_p (exp1->expr, exp2->expr, 0, true);
+   if (equiv_p
+       && exp1->hash != exp2->hash)
+     abort ();
+   return equiv_p;
+ }
+ 
+ 
+ /* Insert expression X in INSN in the hash TABLE.
+    If it is already present, record it as the last occurrence in INSN's
+    basic block.  */
+ 
+ static void
+ insert_expr_in_table (rtx x, rtx insn)
+ {
+   int do_not_record_p;
+   hashval_t hash;
+   struct expr *cur_expr, **slot;
+   struct occr *avail_occr, *last_occr = NULL;
+ 
+   hash = hash_expr (x, &do_not_record_p);
+ 
+   /* Do not insert expression in the table if it contains volatile operands,
+      or if hash_expr determines the expression is something we don't want
+      to or can't handle.  */
+   if (do_not_record_p)
+     return;
+ 
+   /* We anticipate that redundant expressions are rare, so for convenience
+      allocate a new hash table element here already and set its fields.
+      If we don't do this, we need a hack with a static struct expr.  Anyway,
+      obstack_free is really fast and one more obstack_alloc doesn't hurt if
+      we're going to see more expressions later on.  */
+   cur_expr = (struct expr *) obstack_alloc (&expr_obstack,
+ 					    sizeof (struct expr));
+   cur_expr->expr = x;
+   cur_expr->hash = hash;
+   cur_expr->avail_occr = NULL;
+ 
+   slot = (struct expr **) htab_find_slot_with_hash (expr_table, cur_expr,
+ 						    hash, INSERT);
+   
+   if (! (*slot))
+     /* The expression isn't found, so insert it.  */
+     *slot = cur_expr;
+   else
+     {
+       /* The expression is already in the table, so roll back the
+ 	 obstack and use the existing table entry.  */
+       obstack_free (&expr_obstack, cur_expr);
+       cur_expr = *slot;
+     }
+ 
+   /* Search for another occurrence in the same basic block.  */
+   avail_occr = cur_expr->avail_occr;
+   while (avail_occr && BLOCK_NUM (avail_occr->insn) != BLOCK_NUM (insn))
+     {
+       /* If an occurrence isn't found, save a pointer to the end of
+ 	 the list.  */
+       last_occr = avail_occr;
+       avail_occr = avail_occr->next;
+     }
+ 
+   if (avail_occr)
+     /* Found another instance of the expression in the same basic block.
+        Prefer this occurrence to the currently recorded one.  We want
+        the last one in the block and the block is scanned from start
+        to end.  */
+     avail_occr->insn = insn;
+   else
+     {
+       /* First occurrence of this expression in this basic block.  */
+       avail_occr = (struct occr *) obstack_alloc (&occr_obstack,
+ 						  sizeof (struct occr));
+ 
+       /* First occurrence of this expression in any block?  */
+       if (cur_expr->avail_occr == NULL)
+         cur_expr->avail_occr = avail_occr;
+       else
+         last_occr->next = avail_occr;
+ 
+       avail_occr->insn = insn;
+       avail_occr->next = NULL;
+       avail_occr->deleted_p = 0;
+     }
+ }
+ 
+ 
+ /* Lookup pattern PAT in the expression hash table.
+    The result is a pointer to the table entry, or NULL if not found.  */
+ 
+ static struct expr *
+ lookup_expr_in_table (rtx pat)
+ {
+   int do_not_record_p;
+   struct expr **slot, *tmp_expr;
+   hashval_t hash = hash_expr (pat, &do_not_record_p);
+ 
+   if (do_not_record_p)
+     return NULL;
+ 
+   tmp_expr = (struct expr *) obstack_alloc (&expr_obstack,
+ 					    sizeof (struct expr));
+   tmp_expr->expr = pat;
+   tmp_expr->hash = hash;
+   tmp_expr->avail_occr = NULL;
+ 
+   slot = (struct expr **) htab_find_slot_with_hash (expr_table, tmp_expr,
+                                                     hash, INSERT);
+   obstack_free (&expr_obstack, tmp_expr);
+ 
+   if (!slot)
+     return NULL;
+   else
+     return (*slot);
+ }
+ 
+ 
+ /* Dump all expressions and occurences that are currently in the
+    expression hash table to FILE.  */
+ 
+ /* This helper is called via htab_traverse.  */
+ static int
+ dump_hash_table_entry (void **slot, void *filep)
+ {
+   struct expr *expr = (struct expr *) *slot;
+   FILE *file = (FILE *) filep;
+   struct occr *occr;
+ 
+   fprintf (file, "expr: ");
+   print_rtl (file, expr->expr);
+   fprintf (file,"\nhashcode: %u\n", expr->hash);
+   fprintf (file,"list of occurences:\n");
+   occr = expr->avail_occr;
+   while (occr)
+     {
+       rtx insn = occr->insn;
+       print_rtl_single (file, insn);
+       fprintf (file, "\n");
+       occr = occr->next;
+     }
+   fprintf (file, "\n");
+   return 1;
+ }
+ 
+ static void
+ dump_hash_table (FILE *file)
+ {
+   fprintf (file, "\n\nexpression hash table\n");
+   fprintf (file, "size %ld, %ld elements, %f collision/search ratio\n",
+            (long) htab_size (expr_table),
+            (long) htab_elements (expr_table),
+            htab_collisions (expr_table));
+   if (htab_elements (expr_table) > 0)
+     {
+       fprintf (file, "\n\ntable entries:\n");
+       htab_traverse (expr_table, dump_hash_table_entry, file);
+     }
+   fprintf (file, "\n");
+ }
+ 
+ 
+ /* Return nonzero if the operands of expression X are unchanged from the
+    start of INSN's basic block up to but not including INSN if AFTER_INSN
+    is false, or from INSN to the end of INSN's basic block if AFTER_INSN
+    is true.  */
+ 
+ static bool
+ oprs_unchanged_p (rtx x, rtx insn, bool after_insn)
+ {
+   int i, j;
+   enum rtx_code code;
+   const char *fmt;
+ 
+   if (x == 0)
+     return 1;
+ 
+   code = GET_CODE (x);
+   switch (code)
+     {
+     case REG:
+ #ifdef ENABLE_CHECKING
+       /* We are called after register allocation.  */
+       if (REGNO (x) >= FIRST_PSEUDO_REGISTER)
+ 	abort ();
+ #endif
+       if (after_insn)
+ 	/* If the last CUID setting the insn is less than the CUID of
+ 	   INSN, then reg X is not changed in or after INSN.  */
+ 	return reg_avail_info[REGNO (x)] < INSN_CUID (insn);
+       else
+ 	/* Reg X is not set before INSN in the current basic block if
+ 	   we have not yet recorded the CUID of an insn that touches
+ 	   the reg.  */
+ 	return reg_avail_info[REGNO (x)] == 0;
+ 
+     case MEM:
+       if (load_killed_in_block_p (INSN_CUID (insn), x, after_insn))
+ 	return 0;
+       else
+ 	return oprs_unchanged_p (XEXP (x, 0), insn, after_insn);
+ 
+     case PC:
+     case CC0: /*FIXME*/
+     case CONST:
+     case CONST_INT:
+     case CONST_DOUBLE:
+     case CONST_VECTOR:
+     case SYMBOL_REF:
+     case LABEL_REF:
+     case ADDR_VEC:
+     case ADDR_DIFF_VEC:
+       return 1;
+ 
+     case PRE_DEC:
+     case PRE_INC:
+     case POST_DEC:
+     case POST_INC:
+     case PRE_MODIFY:
+     case POST_MODIFY:
+       if (after_insn)
+ 	return 0;
+       break;
+ 
+     default:
+       break;
+     }
+ 
+   for (i = GET_RTX_LENGTH (code) - 1, fmt = GET_RTX_FORMAT (code); i >= 0; i--)
+     {
+       if (fmt[i] == 'e')
+ 	{
+ 	  if (! oprs_unchanged_p (XEXP (x, i), insn, after_insn))
+ 	    return 0;
+ 	}
+       else if (fmt[i] == 'E')
+ 	for (j = 0; j < XVECLEN (x, i); j++)
+ 	  if (! oprs_unchanged_p (XVECEXP (x, i, j), insn, after_insn))
+ 	    return 0;
+     }
+ 
+   return 1;
+ }
+ 
+ 
+ /* Used for communication between find_mem_conflicts and
+    load_killed_in_block_p.  Nonzero if find_mem_conflicts finds a
+    conflict between two memory references.
+    This is a bit of a hack to work around the limitations of note_stores.  */
+ static int mems_conflict_p;
+ 
+ /* DEST is the output of an instruction.  If it is a memory reference, and
+    possibly conflicts with the load found in DATA, then set mems_conflict_p
+    to a nonzero value.  */
+ 
+ static void
+ find_mem_conflicts (rtx dest, rtx setter ATTRIBUTE_UNUSED,
+ 		    void *data)
+ {
+   rtx mem_op = (rtx) data;
+ 
+   while (GET_CODE (dest) == SUBREG
+ 	 || GET_CODE (dest) == ZERO_EXTRACT
+ 	 || GET_CODE (dest) == SIGN_EXTRACT
+ 	 || GET_CODE (dest) == STRICT_LOW_PART)
+     dest = XEXP (dest, 0);
+ 
+   /* If DEST is not a MEM, then it will not conflict with the load.  Note
+      that function calls are assumed to clobber memory, but are handled
+      elsewhere.  */
+   if (! MEM_P (dest))
+     return;
+ 
+   if (true_dependence (dest, GET_MODE (dest), mem_op,
+ 		       rtx_addr_varies_p))
+     mems_conflict_p = 1;
+ }
+ 
+ 
+ /* Return nonzero if the expression in X (a memory reference) is killed
+    in block BB before if (AFTER_INSN is false) or after (if AFTER_INSN
+    is true) the insn with the CUID in UID_LIMIT.  */
+ 
+ static int
+ load_killed_in_block_p (int uid_limit, rtx x, bool after_insn)
+ {
+   struct modifies_mem *list_entry = modifies_mem_list;
+ 
+   while (list_entry)
+     {
+       rtx setter = list_entry->insn;
+ 
+       /* Ignore entries in the list that do not apply.  */
+       if ((after_insn
+ 	   && INSN_CUID (setter) < uid_limit)
+ 	  || (! after_insn
+ 	      && INSN_CUID (setter) > uid_limit))
+ 	{
+ 	  list_entry = list_entry->next;
+ 	  continue;
+ 	}
+ 
+       /* If SETTER is a call everything is clobbered.  Note that calls
+ 	 to pure functions are never put on the list, so we need not
+ 	 worry about them.  */
+       if (CALL_P (setter))
+ 	return 1;
+ 
+       /* SETTER must be an insn of some kind that sets memory.  Call
+ 	 note_stores to examine each hunk of memory that is modified.
+ 	 It will set mems_conflict_p to nonzero if there may be a
+ 	 conflict between X and SETTER.  */
+       mems_conflict_p = 0;
+       note_stores (PATTERN (setter), find_mem_conflicts, x);
+       if (mems_conflict_p)
+ 	return 1;
+ 
+       list_entry = list_entry->next;
+     }
+   return 0;
+ }
+ 
+ 
+ /* Record register first/last/block set information for REGNO in INSN.  */
+ 
+ static void
+ record_last_reg_set_info (rtx insn, int regno)
+ {
+   reg_avail_info[regno] = INSN_CUID (insn);
+ }
+ 
+ 
+ /* Record memory modification information for INSN.  We do not actually care
+    about the memory location(s) that are set, or even how they are set (consider
+    a CALL_INSN).  We merely need to record which insns modify memory.  */
+ 
+ static void
+ record_last_mem_set_info (rtx insn)
+ {
+   struct modifies_mem *list_entry;
+ 
+   list_entry = (struct modifies_mem *) obstack_alloc (&modifies_mem_obstack,
+ 						      sizeof (struct modifies_mem));
+   list_entry->insn = insn;
+   list_entry->next = modifies_mem_list;
+   modifies_mem_list = list_entry;
+ }
+ 
+ /* Called from compute_hash_table via note_stores to handle one
+    SET or CLOBBER in an insn.  DATA is really the instruction in which
+    the SET is taking place.  */
+ 
+ static void
+ record_last_set_info (rtx dest, rtx setter ATTRIBUTE_UNUSED, void *data)
+ {
+   rtx last_set_insn = (rtx) data;
+ 
+   if (GET_CODE (dest) == SUBREG)
+     dest = SUBREG_REG (dest);
+ 
+   if (REG_P (dest))
+     record_last_reg_set_info (last_set_insn, REGNO (dest));
+   else if (MEM_P (dest)
+ 	   /* Ignore pushes, they clobber nothing.  */
+ 	   && ! push_operand (dest, GET_MODE (dest)))
+     record_last_mem_set_info (last_set_insn);
+ }
+ 
+ 
+ /* Reset tables used to keep track of what's still available since the
+    start of the block.  */
+ 
+ static void
+ reset_opr_set_tables (void)
+ {
+   memset (reg_avail_info, 0, FIRST_PSEUDO_REGISTER * sizeof (int));
+   obstack_free (&modifies_mem_obstack, modifies_mem_obstack_bottom);
+   modifies_mem_list = NULL;
+ }
+ 
+ /* Mark things set by a CALL.  */
+ 
+ static void
+ mark_call (rtx insn)
+ {
+   if (! CONST_OR_PURE_CALL_P (insn))
+     record_last_mem_set_info (insn);
+ }
+ 
+ /* Mark things set by a SET.  */
+ 
+ static void
+ mark_set (rtx pat, rtx insn)
+ {
+   rtx dest = SET_DEST (pat);
+ 
+   while (GET_CODE (dest) == SUBREG
+ 	 || GET_CODE (dest) == ZERO_EXTRACT
+ 	 || GET_CODE (dest) == SIGN_EXTRACT
+ 	 || GET_CODE (dest) == STRICT_LOW_PART)
+     dest = XEXP (dest, 0);
+ 
+   if (REG_P (dest))
+     record_last_reg_set_info (insn, REGNO (dest));
+   else if (MEM_P (dest))
+     record_last_mem_set_info (insn);
+ 
+   if (GET_CODE (SET_SRC (pat)) == CALL)
+     mark_call (insn);
+ }
+ 
+ /* Record things set by a CLOBBER.  */
+ 
+ static void
+ mark_clobber (rtx pat, rtx insn)
+ {
+   rtx clob = XEXP (pat, 0);
+ 
+   while (GET_CODE (clob) == SUBREG
+ 	 || GET_CODE (clob) == STRICT_LOW_PART)
+     clob = XEXP (clob, 0);
+ 
+   if (REG_P (clob))
+     record_last_reg_set_info (insn, REGNO (clob));
+   else
+     record_last_mem_set_info (insn);
+ }
+ 
+ /* Record things set by INSN.
+    This data is used by oprs_unchanged_p.  */
+ 
+ static void
+ mark_oprs_set (rtx insn)
+ {
+   rtx pat = PATTERN (insn);
+   int i;
+ 
+   if (GET_CODE (pat) == SET)
+     mark_set (pat, insn);
+ 
+   else if (GET_CODE (pat) == PARALLEL)
+     for (i = 0; i < XVECLEN (pat, 0); i++)
+       {
+ 	rtx x = XVECEXP (pat, 0, i);
+ 
+ 	if (GET_CODE (x) == SET)
+ 	  mark_set (x, insn);
+ 	else if (GET_CODE (x) == CLOBBER)
+ 	  mark_clobber (x, insn);
+ 	else if (GET_CODE (x) == CALL)
+ 	  mark_call (insn);
+       }
+ 
+   else if (GET_CODE (pat) == CLOBBER)
+     mark_clobber (pat, insn);
+ 
+   else if (GET_CODE (pat) == CALL)
+     mark_call (insn);
+ }
+ 
+ 
+ /* Scan the pattern of INSN and add an entry to the hash TABLE.
+    After reload we are interested in loads/stores only.  */
+ 
+ static void
+ hash_scan_set (rtx insn)
+ {
+   rtx pat = PATTERN (insn);
+   rtx src = SET_SRC (pat);
+   rtx dest = SET_DEST (pat);
+ 
+   /* We are only interested in loads and stores.  */
+   if (! MEM_P (src) && ! MEM_P (dest))
+     return;
+ 
+   /* Don't mess with jumps and nops.  */
+   if (JUMP_P (insn) || set_noop_p (pat))
+     return;
+ 
+ #ifdef ENABLE_CHEKCING
+   /* We shouldn't have any EH_REGION notes post reload.  */
+   if (find_reg_note (insn, REG_EH_REGION, NULL_RTX))
+     abort ();
+ #endif
+ 
+   if (REG_P (dest))
+     {
+       if (/* Don't GCSE something if we can't do a reg/reg copy.  */
+ 	  can_copy_p (GET_MODE (dest))
+ 	  /* Is SET_SRC something we want to gcse?  */
+ 	  && general_operand (src, GET_MODE (src))
+ 	  /* An expression is not available if its operands are
+ 	     subsequently modified, including this insn.  */
+ 	  && oprs_unchanged_p (src, insn, true))
+ 	{
+ 	  insert_expr_in_table (src, insn);
+ 	}
+     }
+   else if (REG_P (src))
+     {
+       /* Only record sets of pseudo-regs in the hash table.  */
+       if (/* Don't GCSE something if we can't do a reg/reg copy.  */
+ 	  can_copy_p (GET_MODE (src))
+ 	  /* Is SET_DEST something we want to gcse?  */
+ 	  && general_operand (dest, GET_MODE (dest))
+ 	  && ! (flag_float_store && FLOAT_MODE_P (GET_MODE (dest)))
+ 	  /* Check if the memory expression is killed after insn.  */
+ 	  && ! load_killed_in_block_p (INSN_CUID (insn) + 1, dest, true)
+ 	  && oprs_unchanged_p (XEXP (dest, 0), insn, true))
+ 	{
+ 	  insert_expr_in_table (dest, insn);
+ 	}
+     }
+ }
+ 
+ /* Create hash table of memory expressions available at end of basic
+    blocks.  */
+ 
+ static void
+ compute_hash_table (void)
+ {
+   basic_block bb;
+ 
+   FOR_EACH_BB (bb)
+     {
+       rtx insn;
+       unsigned int regno;
+ 
+       reset_opr_set_tables ();
+ 
+       /* First pass over the instructions records information used to
+ 	 determine when registers and memory are first and last set.  */
+       FOR_BB_INSNS (bb, insn)
+ 	{
+ 	  if (! INSN_P (insn))
+ 	    continue;
+ 
+ 	  if (CALL_P (insn))
+ 	    {
+ 	      bool clobbers_all = false;
+ 
+ #ifdef NON_SAVING_SETJMP
+ 	      if (NON_SAVING_SETJMP
+ 		  && find_reg_note (insn, REG_SETJMP, NULL_RTX))
+ 		clobbers_all = true;
+ #endif
+ 
+ 	      for (regno = 0; regno < FIRST_PSEUDO_REGISTER; regno++)
+ 		if (clobbers_all
+ 		    || TEST_HARD_REG_BIT (regs_invalidated_by_call,
+ 					  regno))
+ 		  record_last_reg_set_info (insn, regno);
+ 
+ 	      if (! CONST_OR_PURE_CALL_P (insn))
+ 		record_last_mem_set_info (insn);
+ 	    }
+ 
+ 	  note_stores (PATTERN (insn), record_last_set_info, insn);
+ 
+ 	  if (GET_CODE (PATTERN (insn)) == SET)
+ 	    {
+ 	      rtx src, dest;
+ 
+ 	      src = SET_SRC (PATTERN (insn));
+ 	      dest = SET_DEST (PATTERN (insn));
+ 	      if (MEM_P (src) && auto_inc_p (XEXP (src, 0)))
+ 		{
+ 		  regno = REGNO (XEXP (XEXP (src, 0), 0));
+ 		  record_last_reg_set_info (insn, regno);
+ 		}
+ 	      if (MEM_P (dest) && auto_inc_p (XEXP (dest, 0)))
+ 		{
+ 		  regno = REGNO (XEXP (XEXP (dest, 0), 0));
+ 		  record_last_reg_set_info (insn, regno);
+ 		}
+ 	     }
+ 	  }
+ 
+       /* The next pass builds the hash table.  */
+       FOR_BB_INSNS (bb, insn)
+ 	if (INSN_P (insn) && GET_CODE (PATTERN (insn)) == SET)
+ 	  hash_scan_set (insn);
+     }
+ }
+ 
+ 
+ /* Check if register REG is killed in any insn waiting to be inserted on
+    edge E.  This function is required to check that our data flow analysis
+    is still valid prior to commit_edge_insertions.  */
+ 
+ static bool
+ reg_killed_on_edge (rtx reg, edge e)
+ {
+   rtx insn;
+ 
+   for (insn = e->insns.r; insn; insn = NEXT_INSN (insn))
+     if (INSN_P (insn) && reg_set_p (reg, insn))
+       return true;
+ 
+   return false;
+ }
+ 
+ /* Similar to above - check if register REG is used in any insn waiting
+    to be inserted on edge E.
+    Assumes no such insn can be a CALL_INSN; if so call reg_used_between_p
+    with PREV(insn),NEXT(insn) instead of calling reg_overlap_mentioned_p.  */
+ 
+ static bool
+ reg_used_on_edge (rtx reg, edge e)
+ {
+   rtx insn;
+ 
+   for (insn = e->insns.r; insn; insn = NEXT_INSN (insn))
+     if (INSN_P (insn) && reg_overlap_mentioned_p (reg, PATTERN (insn)))
+       return true;
+ 
+   return false;
+ }
+ 
+ 
+ /* Return the insn that sets register REG or clobbers it in between
+    FROM_INSN and TO_INSN (exclusive of those two).
+    Just like reg_set_between but for hard registers and not pseudos.  */
+ 
+ static rtx
+ reg_set_between_after_reload_p (rtx reg, rtx from_insn, rtx to_insn)
+ {
+   rtx insn;
+   int regno;
+ 
+ #ifdef ENABLE_CHECKING
+   /* We are called after register allocation.  */
+   if (!REG_P (reg) || REGNO (reg) >= FIRST_PSEUDO_REGISTER)
+     abort ();
+ #endif
+ 
+   if (from_insn == to_insn)
+     return NULL_RTX;
+ 
+   regno = REGNO (reg);
+   for (insn = NEXT_INSN (from_insn);
+        insn != to_insn;
+        insn = NEXT_INSN (insn))
+     {
+       if (INSN_P (insn))
+ 	{
+ 	  if (FIND_REG_INC_NOTE (insn, reg)
+ 	      || (CALL_P (insn)
+ 		  && call_used_regs[regno])
+ 	      || find_reg_fusage (insn, CLOBBER, reg))
+ 	    return insn;
+ 	}
+       if (set_of (reg, insn) != NULL_RTX)
+ 	return insn;
+     }
+ 
+   return NULL_RTX;
+ }
+ 
+ /* Return the insn that uses register REG in between FROM_INSN and TO_INSN
+    (exclusive of those two). Similar to reg_used_between but for hard
+    registers and not pseudos.  */
+ 
+ static rtx
+ reg_used_between_after_reload_p (rtx reg, rtx from_insn, rtx to_insn)
+ {
+   rtx insn;
+   int regno;
+ 
+ #ifdef ENABLE_CHECKING
+   /* We are called after register allocation.  */
+   if (!REG_P (reg) || REGNO (reg) >= FIRST_PSEUDO_REGISTER)
+     abort ();
+ #endif
+ 
+   if (from_insn == to_insn)
+     return NULL_RTX;
+ 
+   regno = REGNO (reg);
+   for (insn = NEXT_INSN (from_insn);
+        insn != to_insn;
+        insn = NEXT_INSN (insn))
+     if (INSN_P (insn)
+ 	&& (reg_overlap_mentioned_p (reg, PATTERN (insn))
+ 	    || (CALL_P (insn)
+ 		&& call_used_regs[regno])
+ 	    || find_reg_fusage (insn, USE, reg)
+ 	    || find_reg_fusage (insn, CLOBBER, reg)))
+       return insn;
+ 
+   return NULL_RTX;
+ }
+ 
+ /* Return true if REG is used, set, or killed between the beginning of
+    basic block BB and UP_TO_INSN.  Caches the result in reg_avail_info.  */
+ 
+ static bool
+ reg_set_or_used_since_bb_start (rtx reg, basic_block bb, rtx up_to_insn)
+ {
+   rtx insn, start = PREV_INSN (BB_HEAD (bb));
+ 
+   if (reg_avail_info[REGNO (reg)] != 0)
+     return true;
+ 
+   insn = reg_used_between_after_reload_p (reg, start, up_to_insn);
+   if (! insn)
+     insn = reg_set_between_after_reload_p (reg, start, up_to_insn);
+ 
+   if (insn)
+     reg_avail_info[REGNO (reg)] = INSN_CUID (insn);
+ 
+   return insn != NULL_RTX;
+ }
+ 
+ /* Return the loaded/stored register of a load/store instruction.  */
+ 
+ static rtx
+ get_avail_load_store_reg (rtx insn)
+ {
+   if (REG_P (SET_DEST (PATTERN (insn))))  /* A load.  */
+     return SET_DEST(PATTERN(insn));
+   if (REG_P (SET_SRC (PATTERN (insn))))  /* A store.  */
+     return SET_SRC (PATTERN (insn));
+   abort ();
+ }
+ 
+ /* Return nonzero if the predecessors of BB are "well behaved".  */
+ 
+ static bool
+ bb_has_well_behaved_predecessors (basic_block bb)
+ {
+   edge pred;
+ 
+   if (! bb->pred)
+     return false;
+ 
+   for (pred = bb->pred; pred != NULL; pred = pred->pred_next)
+     {
+       if ((pred->flags & EDGE_ABNORMAL) && EDGE_CRITICAL_P (pred))
+ 	return false;
+ 
+       if (JUMP_TABLE_DATA_P (BB_END (pred->src)))
+ 	return false;
+     }
+   return true;
+ }
+ 
+ 
+ /* Search for the occurrences of expression in BB.  */
+ 
+ static struct occr*
+ get_bb_avail_insn (basic_block bb, struct occr *occr)
+ {
+   for (; occr != NULL; occr = occr->next)
+     if (BLOCK_FOR_INSN (occr->insn) == bb)
+       return occr;
+   return NULL;
+ }
+ 
+ 
+ /* This handles the case where several stores feed a partially redundant
+    load. It checks if the redundancy elimination is possible and if it's
+    worth it.  */
+ 
+ static void
+ eliminate_partially_redundant_load (basic_block bb, rtx insn,
+ 				    struct expr *expr)
+ {
+   edge pred;
+   rtx avail_insn = NULL_RTX;
+   rtx avail_reg;
+   rtx dest, pat;
+   struct occr *a_occr;
+   struct unoccr *occr, *avail_occrs = NULL;
+   struct unoccr *unoccr, *unavail_occrs = NULL, *rollback_unoccr = NULL;
+   int npred_ok = 0;
+   gcov_type ok_count = 0; /* Redundant load execution count.  */
+   gcov_type critical_count = 0; /* Execution count of critical edges.  */
+ 
+   /* The execution count of the loads to be added to make the
+      load fully redundant.  */
+   gcov_type not_ok_count = 0;
+   basic_block pred_bb;
+ 
+   pat = PATTERN (insn);
+   dest = SET_DEST (pat);
+ 
+   /* Check that the loaded register is not used, set, or killed from the
+      beginning of the block.  */
+   if (reg_set_or_used_since_bb_start (dest, bb, insn))
+     return;
+ 
+   /* Check potential for replacing load with copy for predecessors.  */
+   for (pred = bb->pred; pred; pred = pred->pred_next)
+     {
+       rtx next_pred_bb_end;
+ 
+       avail_insn = NULL_RTX;
+       pred_bb = pred->src;
+       next_pred_bb_end = NEXT_INSN (BB_END (pred_bb));
+       for (a_occr = get_bb_avail_insn (pred_bb, expr->avail_occr); a_occr;
+ 	   a_occr = get_bb_avail_insn (pred_bb, a_occr->next))
+ 	{
+ 	  /* Check if the loaded register is not used.  */
+ 	  avail_insn = a_occr->insn;
+ 	  if (! (avail_reg = get_avail_load_store_reg (avail_insn)))
+ 	    abort ();
+ 	  /* Make sure we can generate a move from register avail_reg to
+ 	     dest.  */
+ 	  extract_insn (gen_move_insn (copy_rtx (dest),
+ 				       copy_rtx (avail_reg)));
+ 	  if (! constrain_operands (1)
+ 	      || reg_killed_on_edge (avail_reg, pred)
+ 	      || reg_used_on_edge (dest, pred))
+ 	    {
+ 	      avail_insn = NULL;
+ 	      continue;
+ 	    }
+ 	  if (! reg_set_between_after_reload_p (avail_reg, avail_insn,
+ 						next_pred_bb_end))
+ 	    /* AVAIL_INSN remains non-null.  */
+ 	    break;
+ 	  else
+ 	    avail_insn = NULL;
+ 	}
+ 
+       if (EDGE_CRITICAL_P (pred))
+ 	critical_count += pred->count;
+ 
+       if (avail_insn != NULL_RTX)
+ 	{
+ 	  npred_ok++;
+ 	  ok_count += pred->count;
+ 	  occr = (struct unoccr *) obstack_alloc (&unoccr_obstack,
+ 						  sizeof (struct occr));
+ 	  occr->insn = avail_insn;
+ 	  occr->pred = pred;
+ 	  occr->next = avail_occrs;
+ 	  avail_occrs = occr;
+ 	  if (! rollback_unoccr)
+ 	    rollback_unoccr = occr;
+ 	}
+       else
+ 	{
+ 	  not_ok_count += pred->count;
+ 	  unoccr = (struct unoccr *) obstack_alloc (&unoccr_obstack,
+ 						    sizeof (struct unoccr));
+ 	  unoccr->insn = NULL_RTX;
+ 	  unoccr->pred = pred;
+ 	  unoccr->next = unavail_occrs;
+ 	  unavail_occrs = unoccr;
+ 	  if (! rollback_unoccr)
+ 	    rollback_unoccr = unoccr;
+ 	}
+     }
+ 
+   if (/* No load can be replaced by copy.  */
+       npred_ok == 0
+       /* Prevent exploding the code.  */ 
+       || (optimize_size && npred_ok > 1))
+     goto cleanup;
+ 
+   /* Check if it's worth applying the partial redundancy elimination.  */
+   if (ok_count < GCSE_AFTER_RELOAD_PARTIAL_FRACTION * not_ok_count)
+     goto cleanup;
+   if (ok_count < GCSE_AFTER_RELOAD_CRITICAL_FRACTION * critical_count)
+     goto cleanup;
+ 
+   /* Generate moves to the loaded register from where
+      the memory is available.  */
+   for (occr = avail_occrs; occr; occr = occr->next)
+     {
+       avail_insn = occr->insn;
+       pred = occr->pred;
+       /* Set avail_reg to be the register having the value of the
+ 	 memory.  */
+       avail_reg = get_avail_load_store_reg (avail_insn);
+       if (! avail_reg)
+ 	abort ();
+ 
+       insert_insn_on_edge (gen_move_insn (copy_rtx (dest),
+ 					  copy_rtx (avail_reg)),
+ 			   pred);
+       stats.moves_inserted++;
+ 
+       if (dump_file)
+ 	fprintf (dump_file,
+ 		 "generating move from %d to %d on edge from %d to %d\n",
+ 		 REGNO (avail_reg),
+ 		 REGNO (dest),
+ 		 pred->src->index,
+ 		 pred->dest->index);
+     }
+ 
+   /* Regenerate loads where the memory is unavailable.  */
+   for (unoccr = unavail_occrs; unoccr; unoccr = unoccr->next)
+     {
+       pred = unoccr->pred;
+       insert_insn_on_edge (copy_insn (PATTERN (insn)), pred);
+       stats.copies_inserted++;
+ 
+       if (dump_file)
+ 	{
+ 	  fprintf (dump_file,
+ 		   "generating on edge from %d to %d a copy of load: ",
+ 		   pred->src->index,
+ 		   pred->dest->index);
+ 	  print_rtl (dump_file, PATTERN (insn));
+ 	  fprintf (dump_file, "\n");
+ 	}
+     }
+ 
+   /* Delete the insn if it is not available in this block and mark it
+      for deletion if it is available. If insn is available it may help
+      discover additional redundancies, so mark it for later deletion.  */
+   for (a_occr = get_bb_avail_insn (bb, expr->avail_occr);
+        a_occr && (a_occr->insn != insn);
+        a_occr = get_bb_avail_insn (bb, a_occr->next));
+ 
+   if (!a_occr)
+     delete_insn (insn);
+   else
+     a_occr->deleted_p = 1;
+ 
+ cleanup:
+   if (rollback_unoccr)
+     obstack_free (&unoccr_obstack, rollback_unoccr);
+ }
+ 
+ /* Performing the redundancy elimination as described before.  */
+ 
+ static void
+ eliminate_partially_redundant_loads (void)
+ {
+   rtx insn;
+   basic_block bb;
+ 
+   /* Note we start at block 1.  */
+ 
+   if (ENTRY_BLOCK_PTR->next_bb == EXIT_BLOCK_PTR)
+     return;
+ 
+   FOR_BB_BETWEEN (bb,
+ 		  ENTRY_BLOCK_PTR->next_bb->next_bb,
+ 		  EXIT_BLOCK_PTR,
+ 		  next_bb)
+     {
+       if (! bb_has_well_behaved_predecessors (bb))
+ 	continue;
+ 
+       /* Do not try this optimization on cold basic blocks.  */
+       if (probably_cold_bb_p (bb))
+ 	continue;
+ 
+       reset_opr_set_tables ();
+ 
+       FOR_BB_INSNS (bb, insn)
+ 	{
+ 	  /* Is it a load - of the form (set (reg) (mem))?  */
+ 	  if (NONJUMP_INSN_P (insn)
+               && GET_CODE (PATTERN (insn)) == SET
+ 	      && REG_P (SET_DEST (PATTERN (insn)))
+ 	      && MEM_P (SET_SRC (PATTERN (insn))))
+ 	    {
+ 	      rtx pat = PATTERN (insn);
+ 	      rtx src = SET_SRC (pat);
+ 	      struct expr *expr;
+ 
+ 	      if (!MEM_VOLATILE_P (src)
+ 		  && GET_MODE (src) != BLKmode
+ 		  && general_operand (src, GET_MODE (src))
+ 		  /* Are the operands unchanged since the start of the
+ 		     block?  */
+ 		  && oprs_unchanged_p (src, insn, false)
+ 		  && !(flag_non_call_exceptions && may_trap_p (src))
+ 		  && !side_effects_p (src)
+ 		  /* Is the expression recorded?  */
+ 		  && (expr = lookup_expr_in_table (src)) != NULL)
+ 		{
+ 		  /* We now have a load (insn) and an available memory at
+ 		     its BB start (expr). Try to remove the loads if it is
+ 		     redundant.  */
+ 		  eliminate_partially_redundant_load (bb, insn, expr);
+ 		}
+ 	    }
+ 
+ 	  /* Keep track of everything modified by this insn.  */
+ 	  if (INSN_P (insn))
+ 	    mark_oprs_set (insn);
+ 	}
+     }
+ 
+   commit_edge_insertions ();
+ }
+ 
+ /* Go over the expression hash table and delete insns that were
+    marked for later deletion.  */
+ 
+ /* This helper is called via htab_traverse.  */
+ static int
+ delete_redundant_insns_1 (void **slot, void *data ATTRIBUTE_UNUSED)
+ {
+   struct expr *expr = (struct expr *) *slot;
+   struct occr *occr;
+ 
+   for (occr = expr->avail_occr; occr != NULL; occr = occr->next)
+     {
+       if (occr->deleted_p)
+ 	{
+ 	  delete_insn (occr->insn);
+ 	  stats.insns_deleted++;
+ 
+ 	  if (dump_file)
+ 	    {
+ 	      fprintf (dump_file, "deleting insn:\n");
+ 	      print_rtl_single (dump_file, occr->insn);
+ 	      fprintf (dump_file, "\n");
+ 	    }
+ 	}
+     }
+ 
+   return 1;
+ }
+ 
+ static void
+ delete_redundant_insns (void)
+ {
+   htab_traverse (expr_table, delete_redundant_insns_1, NULL);
+   if (dump_file)
+     fprintf (dump_file, "\n");
+ }
+ 
+ /* Main entry point of the GCSE after reload - clean some redundant loads
+    due to spilling.  */
+ 
+ void
+ gcse_after_reload_main (rtx f ATTRIBUTE_UNUSED)
+ {
+   memset (&stats, 0, sizeof (stats));
+ 
+   /* Allocate ememory for this pass.
+      Also computes and initializes the insns' CUIDs.  */
+   alloc_mem ();
+ 
+   /* We need alias analysis.  */
+   init_alias_analysis ();
+ 
+   compute_hash_table ();
+ 
+   if (dump_file)
+     dump_hash_table (dump_file);
+ 
+   if (htab_elements (expr_table) > 0)
+     {
+       eliminate_partially_redundant_loads ();
+       delete_redundant_insns ();
+ 
+       if (dump_file)
+ 	{
+ 	  fprintf (dump_file, "GCSE AFTER RELOAD stats:\n");
+ 	  fprintf (dump_file, "copies inserted: %d\n", stats.copies_inserted);
+ 	  fprintf (dump_file, "moves inserted:  %d\n", stats.moves_inserted);
+ 	  fprintf (dump_file, "insns deleted:   %d\n", stats.insns_deleted);
+ 	  fprintf (dump_file, "\n\n");
+ 	}
+     }
+     
+   /* We are finished with alias.  */
+   end_alias_analysis ();
+ 
+   free_mem ();
+ }
+ 
Index: rtl.h
===================================================================
RCS file: /cvs/gcc/gcc/gcc/rtl.h,v
retrieving revision 1.502
diff -c -3 -p -r1.502 rtl.h
*** rtl.h	18 Aug 2004 08:24:11 -0000	1.502
--- rtl.h	18 Aug 2004 17:51:31 -0000
*************** extern int rtx_to_tree_code (enum rtx_co
*** 2119,2124 ****
--- 2119,2126 ----
  extern int delete_trivially_dead_insns (rtx, int);
  extern int cse_main (rtx, int, int, FILE *);
  extern void cse_condition_code_reg (void);
+ extern int exp_equiv_p (rtx, rtx, int, bool);
+ extern unsigned hash_rtx (rtx x, enum machine_mode, int *, int *, bool);
  
  /* In jump.c */
  extern int comparison_dominates_p (enum rtx_code, enum rtx_code);
*************** extern bool can_copy_p (enum machine_mod
*** 2265,2271 ****
  extern rtx fis_get_condition (rtx);
  extern int gcse_main (rtx, FILE *);
  extern int bypass_jumps (FILE *);
! extern void gcse_after_reload_main (rtx, FILE *);
  
  /* In global.c */
  extern void mark_elimination (int, int);
--- 2267,2275 ----
  extern rtx fis_get_condition (rtx);
  extern int gcse_main (rtx, FILE *);
  extern int bypass_jumps (FILE *);
! 
! /* In postreload-gcse.c */
! extern void gcse_after_reload_main (rtx);
  
  /* In global.c */
  extern void mark_elimination (int, int);
Index: timevar.def
===================================================================
RCS file: /cvs/gcc/gcc/gcc/timevar.def,v
retrieving revision 1.32
diff -c -3 -p -r1.32 timevar.def
*** timevar.def	17 Aug 2004 16:17:03 -0000	1.32
--- timevar.def	18 Aug 2004 17:51:31 -0000
*************** DEFTIMEVAR (TV_SCHED                 , "
*** 122,127 ****
--- 122,128 ----
  DEFTIMEVAR (TV_LOCAL_ALLOC           , "local alloc")
  DEFTIMEVAR (TV_GLOBAL_ALLOC          , "global alloc")
  DEFTIMEVAR (TV_RELOAD_CSE_REGS       , "reload CSE regs")
+ DEFTIMEVAR (TV_GCSE_AFTER_RELOAD      , "load CSE after reload")
  DEFTIMEVAR (TV_FLOW2                 , "flow 2")
  DEFTIMEVAR (TV_IFCVT2		     , "if-conversion 2")
  DEFTIMEVAR (TV_PEEPHOLE2             , "peephole 2")

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