diff mbox

Cleanup tree-ssa-ter.c exports

Message ID 52322D91.8000706@redhat.com
State New
Headers show

Commit Message

Andrew MacLeod Sept. 12, 2013, 9:09 p.m. UTC 
There are 2 parts of tre-ssa-ter.c to address.

is_replaceable_p() is also used in expr.c, It has a flag to indicate 
where its being called from, and we do different checks for each one.  
There is a wrapper function stmt_is_replaceable_p() in tree-ssa-ter.c 
which hides the setting of the flag to expr.c. Most of the function is 
common, so I extracted out the common part, and put it in tree-ssa.c.
I then moved stmt_is_replaceable() to expr.c, has it call the common 
routine and then added the extra bit it needs there.  Similarly 
tree-ssa-ter.c gets  ter_is_replaceable_p() which calls the common part, 
and then does its own special checking.   This removes that general 
export and messiness from tree-ssa-ter.c

I think I got the logic of the function right, but you might want to 
double check...  It was giving me a headache when I split it :-)

Unfortunately,  tree-ssa-ter.c also has 2 functions 
(find_replaceable_exprs() and  dump_replaceable_exprs()) which are 
exported and utilized by tree-outof-ssa.c  (the file is a part of the 
out-of-ssa module).  So I moved the prototypes from tree-ssa-live.h into 
a newly created tree-ssa-ter.h file,  and included it directly from 
tree-outof-ssa.c, the only consumer.

I also could have just left the is_replaceable_p() function as is, put 
the prototype and the 'stmt_is_replaceable_p()' wrapper function in 
tree-ssa-ter.h, and then included that from expr.c...  but it just seems 
like an odd thing to include directly there....  but that is an option...

eventually we mighty want to look at splitting expr.c.. it seems a bit 
multi-personality with some pure RTL, some tree/rtl and some ssa...   
even though they all serve the same ultimate function, it is 11,000+ 
lines long now :-) .  A task for another day.

Passes bootstrap with no new regressions on x86_64-unknown-linux-gnu.

Andrew

Comments

Richard Biener Sept. 13, 2013, 7:54 a.m. UTC | #1 
On Thu, Sep 12, 2013 at 11:09 PM, Andrew MacLeod <amacleod@redhat.com> wrote:
> There are 2 parts of tre-ssa-ter.c to address.
>
> is_replaceable_p() is also used in expr.c, It has a flag to indicate where
> its being called from, and we do different checks for each one.  There is a
> wrapper function stmt_is_replaceable_p() in tree-ssa-ter.c which hides the
> setting of the flag to expr.c. Most of the function is common, so I
> extracted out the common part, and put it in tree-ssa.c.
> I then moved stmt_is_replaceable() to expr.c, has it call the common routine
> and then added the extra bit it needs there.  Similarly tree-ssa-ter.c gets
> ter_is_replaceable_p() which calls the common part, and then does its own
> special checking.   This removes that general export and messiness from
> tree-ssa-ter.c
>
> I think I got the logic of the function right, but you might want to double
> check...  It was giving me a headache when I split it :-)
>
> Unfortunately,  tree-ssa-ter.c also has 2 functions
> (find_replaceable_exprs() and  dump_replaceable_exprs()) which are exported
> and utilized by tree-outof-ssa.c  (the file is a part of the out-of-ssa
> module).  So I moved the prototypes from tree-ssa-live.h into a newly
> created tree-ssa-ter.h file,  and included it directly from
> tree-outof-ssa.c, the only consumer.
>
> I also could have just left the is_replaceable_p() function as is, put the
> prototype and the 'stmt_is_replaceable_p()' wrapper function in
> tree-ssa-ter.h, and then included that from expr.c...  but it just seems
> like an odd thing to include directly there....  but that is an option...
>
> eventually we mighty want to look at splitting expr.c.. it seems a bit
> multi-personality with some pure RTL, some tree/rtl and some ssa...   even
> though they all serve the same ultimate function, it is 11,000+ lines long
> now :-) .  A task for another day.

is_replaceable_p and friends is purely specific to the area of RTL expansion,
so putting it in tree-ssa.[ch] is definitely wrong.  It doesn't make sense to
use it anywhere else.

The main driver of the RTL expansion process is in cfgexpand.c (the expand
pass itself) in gimple_expand_cfg.  We have one header file related to
the RTL expansion process and is_replaceable_p would simply fit in
ssaexpand.h (which doesn't have a .c file, so leaving the stuff in the .c files
where they are now is ok).

So - I fear you have to re-do this patch (in a much simpler way).

Thanks,
Richard.







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[patch] Cleanup tree-ssa-ter.c exports
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Andrew MacLeod
11:09 PM (10 hours ago)


to gcc-patches, me, Diego
There are 2 parts of tre-ssa-ter.c to address.

is_replaceable_p() is also used in expr.c, It has a flag to indicate
where its being called from, and we do different checks for each one.
There is a wrapper function stmt_is_replaceable_p() in tree-ssa-ter.c
which hides the setting of the flag to expr.c. Most of the function is
common, so I extracted out the common part, and put it in tree-ssa.c.
I then moved stmt_is_replaceable() to expr.c, has it call the common
routine and then added the extra bit it needs there.  Similarly
tree-ssa-ter.c gets  ter_is_replaceable_p() which calls the common
part, and then does its own special checking.   This removes that
general export and messiness from tree-ssa-ter.c

I think I got the logic of the function right, but you might want to
double check...  It was giving me a headache when I split it :-)

Unfortunately,  tree-ssa-ter.c also has 2 functions
(find_replaceable_exprs() and  dump_replaceable_exprs()) which are
exported and utilized by tree-outof-ssa.c  (the file is a part of the
out-of-ssa module).  So I moved the prototypes from tree-ssa-live.h
into a newly created tree-ssa-ter.h file,  and included it directly
from tree-outof-ssa.c, the only consumer.

I also could have just left the is_replaceable_p() function as is, put
the prototype and the 'stmt_is_replaceable_p()' wrapper function in
tree-ssa-ter.h, and then included that from expr.c...  but it just
seems like an odd thing to include directly there....  but that is an
option...

eventually we mighty want to look at splitting expr.c.. it seems a bit
multi-personality with some pure RTL, some tree/rtl and some ssa...
even though they all serve the same ultimate function, it is 11,000+
lines long now :-) .  A task for another day.

Passes bootstrap with no new regressions on x86_64-unknown-linux-gnu.
r4.diff
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> Passes bootstrap with no new regressions on x86_64-unknown-linux-gnu.
>
> Andrew
Andrew MacLeod Sept. 13, 2013, 3:11 p.m. UTC | #2 
On 09/13/2013 03:54 AM, Richard Biener wrote:
> On Thu, Sep 12, 2013 at 11:09 PM, Andrew MacLeod <amacleod@redhat.com> wrote:
>> There are 2 parts of tre-ssa-ter.c to address.
>>
>> is_replaceable_p() is also used in expr.c, It has a flag to indicate where
>> its being called from, and we do different checks for each one.  There is a
>> wrapper function stmt_is_replaceable_p() in tree-ssa-ter.c which hides the
>> setting of the flag to expr.c. Most of the function is common, so I
>> extracted out the common part, and put it in tree-ssa.c.
>> I then moved stmt_is_replaceable() to expr.c, has it call the common routine
>> and then added the extra bit it needs there.  Similarly tree-ssa-ter.c gets
>> ter_is_replaceable_p() which calls the common part, and then does its own
>> special checking.   This removes that general export and messiness from
>> tree-ssa-ter.c
>>
>> I think I got the logic of the function right, but you might want to double
>> check...  It was giving me a headache when I split it :-)
>>
>> Unfortunately,  tree-ssa-ter.c also has 2 functions
>> (find_replaceable_exprs() and  dump_replaceable_exprs()) which are exported
>> and utilized by tree-outof-ssa.c  (the file is a part of the out-of-ssa
>> module).  So I moved the prototypes from tree-ssa-live.h into a newly
>> created tree-ssa-ter.h file,  and included it directly from
>> tree-outof-ssa.c, the only consumer.
>>
>> I also could have just left the is_replaceable_p() function as is, put the
>> prototype and the 'stmt_is_replaceable_p()' wrapper function in
>> tree-ssa-ter.h, and then included that from expr.c...  but it just seems
>> like an odd thing to include directly there....  but that is an option...
>>
>> eventually we mighty want to look at splitting expr.c.. it seems a bit
>> multi-personality with some pure RTL, some tree/rtl and some ssa...   even
>> though they all serve the same ultimate function, it is 11,000+ lines long
>> now :-) .  A task for another day.
> is_replaceable_p and friends is purely specific to the area of RTL expansion,
> so putting it in tree-ssa.[ch] is definitely wrong.  It doesn't make sense to
> use it anywhere else.
>
> The main driver of the RTL expansion process is in cfgexpand.c (the expand
> pass itself) in gimple_expand_cfg.  We have one header file related to
> the RTL expansion process and is_replaceable_p would simply fit in
> ssaexpand.h (which doesn't have a .c file, so leaving the stuff in the .c files
> where they are now is ok).
>
> So - I fear you have to re-do this patch (in a much simpler way).
>
I actually figured as much :-)  I had actually done that split before I 
remembered there were other exports, and considered undoing that part, 
but figured since I had done it I'd get opinion :-)

Or are you suggesting we also bail on tree-ssa-ter.h and put those 
prototypes in ssaexpand.h?

If we want to make this fully consistent (.h's match .c exports) , I 
could put is_replaceable_p() into a new ssaexpand.c, move the 3 
tree-outof-ssa prototypes in ssaexpand.h into tree-outof-ssa.h, and have 
ssaexpand.h include tree-ssa-ter.h and tree-outof-ssa.h.   That would 
then be clean. and consistent.

actually, we could just make is_replaceable_p() static inline in 
ssaexpand.h...  thats not unreasonable either, but we'll probably find 
functions which belong in ssaexpand.c sooner or later.

No worries, I figured these first few patches would be slower and more 
painful until a reasonable formula was determined :-)


Andrew
Eric Botcazou Oct. 20, 2013, 1:53 p.m. UTC | #3 
> Unfortunately,  tree-ssa-ter.c also has 2 functions
> (find_replaceable_exprs() and  dump_replaceable_exprs()) which are
> exported and utilized by tree-outof-ssa.c  (the file is a part of the
> out-of-ssa module).  So I moved the prototypes from tree-ssa-live.h into
> a newly created tree-ssa-ter.h file,  and included it directly from
> tree-outof-ssa.c, the only consumer.

Apparently something went wrong when tree-ssa-ter.h was created.
Andrew MacLeod Oct. 21, 2013, 1:08 p.m. UTC | #4 
On 10/20/2013 09:53 AM, Eric Botcazou wrote:
>> Unfortunately,  tree-ssa-ter.c also has 2 functions
>> (find_replaceable_exprs() and  dump_replaceable_exprs()) which are
>> exported and utilized by tree-outof-ssa.c  (the file is a part of the
>> out-of-ssa module).  So I moved the prototypes from tree-ssa-live.h into
>> a newly created tree-ssa-ter.h file,  and included it directly from
>> tree-outof-ssa.c, the only consumer.
> Apparently something went wrong when tree-ssa-ter.h was created.
>
what went wrong?  I see it in my checkouts...?

Andrew
Eric Botcazou Oct. 21, 2013, 11:56 p.m. UTC | #5 
> what went wrong?  I see it in my checkouts...?

Just open the file in your preferred editor. :-)
diff mbox

Patch


	* tree-flow.h (stmt_is_replaceable_p): Remove prototype.
	* tree-ssa.c (ssa_is_replaceable_p): Import common bits of 
	is_replaceable_p from tree-ssa-ter.c
	* tree-ssa.h (ssa_is_replaceable_p): Add prototype.
	* tree-ssa-ter.c (is_replaceable_p, stmt_is_replaceable_p): Delete.
	(ter_is_replaceable_p): Use new refactored ssa_is_replaceable_p.
	(process_replaceable): Use ter_is_replaceable_p.
	(find_replaceable_in_bb): Use ter_is_replaceable_p.
	* expr.c (stmt_is_replaceable_p): Relocate from tree-ssa-ter.c.  Use new
	refactored ssa_is_replaceable_p.
	* tree-ssa-live.h (find_replaceable_exprs, dump_replaceable_exprs): Move
	prototypes to new header file.
	* tree-ssa-ter.h: New file.  Move prototypes here.
	* tree-outof-ssa.c: Include tree-ssa-ter.h
	* Makefile.in: Change Dependencies.



Index: tree-flow.h
===================================================================
*** tree-flow.h	(revision 202527)
--- tree-flow.h	(working copy)
*************** bool fixup_noreturn_call (gimple stmt);
*** 686,694 ****
  /* In ipa-pure-const.c  */
  void warn_function_noreturn (tree);
  
- /* In tree-ssa-ter.c  */
- bool stmt_is_replaceable_p (gimple);
- 
  /* In tree-parloops.c  */
  bool parallelized_function_p (tree);
  
--- 686,691 ----
Index: tree-ssa.c
===================================================================
*** tree-ssa.c	(revision 202525)
--- tree-ssa.c	(working copy)
*************** tree_ssa_strip_useless_type_conversions
*** 1182,1187 ****
--- 1182,1244 ----
  }
  
  
+ /* Return TRUE if expression STMT is suitable for replacement.  */
+ 
+ bool
+ ssa_is_replaceable_p (gimple stmt)
+ {
+   use_operand_p use_p;
+   tree def;
+   gimple use_stmt;
+ 
+   /* Only consider modify stmts.  */
+   if (!is_gimple_assign (stmt))
+     return false;
+ 
+   /* If the statement may throw an exception, it cannot be replaced.  */
+   if (stmt_could_throw_p (stmt))
+     return false;
+ 
+   /* Punt if there is more than 1 def.  */
+   def = SINGLE_SSA_TREE_OPERAND (stmt, SSA_OP_DEF);
+   if (!def)
+     return false;
+ 
+   /* Only consider definitions which have a single use.  */
+   if (!single_imm_use (def, &use_p, &use_stmt))
+     return false;
+ 
+   /* Used in this block, but at the TOP of the block, not the end.  */
+   if (gimple_code (use_stmt) == GIMPLE_PHI)
+     return false;
+ 
+   /* There must be no VDEFs.  */
+   if (gimple_vdef (stmt))
+     return false;
+ 
+   /* Float expressions must go through memory if float-store is on.  */
+   if (flag_float_store
+       && FLOAT_TYPE_P (gimple_expr_type (stmt)))
+     return false;
+ 
+   /* An assignment with a register variable on the RHS is not
+      replaceable.  */
+   if (gimple_assign_rhs_code (stmt) == VAR_DECL
+       && DECL_HARD_REGISTER (gimple_assign_rhs1 (stmt)))
+     return false;
+ 
+   /* No function calls can be replaced.  */
+   if (is_gimple_call (stmt))
+     return false;
+ 
+   /* Leave any stmt with volatile operands alone as well.  */
+   if (gimple_has_volatile_ops (stmt))
+     return false;
+ 
+   return true;
+ }
+ 
+ 
  /* Internal helper for walk_use_def_chains.  VAR, FN and DATA are as
     described in walk_use_def_chains.
  
Index: tree-ssa.h
===================================================================
*** tree-ssa.h	(revision 202527)
--- tree-ssa.h	(working copy)
*************** extern void warn_uninit (enum opt_code,
*** 62,67 ****
--- 62,70 ----
  extern unsigned int warn_uninitialized_vars (bool);
  extern void execute_update_addresses_taken (void);
  
+ /* Check to see if a stmt contains basic replaceable expressions.  */
+ extern bool ssa_is_replaceable_p (gimple stmt);
+ 
  /* Given an edge_var_map V, return the PHI arg definition.  */
  
  static inline tree
Index: tree-ssa-ter.c
===================================================================
*** tree-ssa-ter.c	(revision 202525)
--- tree-ssa-ter.c	(working copy)
*************** along with GCC; see the file COPYING3.
*** 46,52 ****
     information is tracked.
  
     Variables which only have one use, and whose defining stmt is considered
!    a replaceable expression (see is_replaceable_p) are tracked to see whether
     they can be replaced at their use location.
  
     n_12 = C * 10
--- 46,52 ----
     information is tracked.
  
     Variables which only have one use, and whose defining stmt is considered
!    a replaceable expression (see ssa_is_replaceable_p) are tracked to see whether
     they can be replaced at their use location.
  
     n_12 = C * 10
*************** add_dependence (temp_expr_table_p tab, i
*** 360,466 ****
  
  
  /* Return TRUE if expression STMT is suitable for replacement.
!    TER is true if is_replaceable_p is called from within TER, false
!    when used from within stmt_is_replaceable_p, i.e. EXPAND_INITIALIZER
!    expansion.  The differences are that with !TER some tests are skipped
!    to make it more aggressive (doesn't require the same bb, or for -O0
!    same locus and same BLOCK), on the other side never considers memory
!    loads as replaceable, because those don't ever lead into constant
!    expressions.  */
  
  static inline bool
! is_replaceable_p (gimple stmt, bool ter)
  {
-   use_operand_p use_p;
-   tree def;
-   gimple use_stmt;
-   location_t locus1, locus2;
-   tree block1, block2;
  
!   /* Only consider modify stmts.  */
!   if (!is_gimple_assign (stmt))
!     return false;
! 
!   /* If the statement may throw an exception, it cannot be replaced.  */
!   if (stmt_could_throw_p (stmt))
!     return false;
! 
!   /* Punt if there is more than 1 def.  */
!   def = SINGLE_SSA_TREE_OPERAND (stmt, SSA_OP_DEF);
!   if (!def)
!     return false;
! 
!   /* Only consider definitions which have a single use.  */
!   if (!single_imm_use (def, &use_p, &use_stmt))
!     return false;
! 
!   /* If the use isn't in this block, it wont be replaced either.  */
!   if (ter && gimple_bb (use_stmt) != gimple_bb (stmt))
!     return false;
! 
!   locus1 = gimple_location (stmt);
!   block1 = LOCATION_BLOCK (locus1);
!   locus1 = LOCATION_LOCUS (locus1);
! 
!   if (gimple_code (use_stmt) == GIMPLE_PHI)
!     locus2 = gimple_phi_arg_location (use_stmt, PHI_ARG_INDEX_FROM_USE (use_p));
!   else
!     locus2 = gimple_location (use_stmt);
!   block2 = LOCATION_BLOCK (locus2);
!   locus2 = LOCATION_LOCUS (locus2);
! 
!   if ((!optimize || optimize_debug)
!       && ter
!       && ((locus1 != UNKNOWN_LOCATION
! 	   && locus1 != locus2)
! 	  || (block1 != NULL_TREE
! 	      && block1 != block2)))
!     return false;
! 
!   /* Used in this block, but at the TOP of the block, not the end.  */
!   if (gimple_code (use_stmt) == GIMPLE_PHI)
!     return false;
! 
!   /* There must be no VDEFs.  */
!   if (gimple_vdef (stmt))
!     return false;
! 
!   /* Without alias info we can't move around loads.  */
!   if ((!optimize || !ter)
!       && gimple_assign_single_p (stmt)
!       && !is_gimple_val (gimple_assign_rhs1 (stmt)))
!     return false;
! 
!   /* Float expressions must go through memory if float-store is on.  */
!   if (flag_float_store
!       && FLOAT_TYPE_P (gimple_expr_type (stmt)))
!     return false;
! 
!   /* An assignment with a register variable on the RHS is not
!      replaceable.  */
!   if (gimple_assign_rhs_code (stmt) == VAR_DECL
!       && DECL_HARD_REGISTER (gimple_assign_rhs1 (stmt)))
!     return false;
! 
!   /* No function calls can be replaced.  */
!   if (is_gimple_call (stmt))
!     return false;
! 
!   /* Leave any stmt with volatile operands alone as well.  */
!   if (gimple_has_volatile_ops (stmt))
!     return false;
! 
!   return true;
! }
! 
! 
! /* Variant of is_replaceable_p test for use in EXPAND_INITIALIZER
!    expansion.  */
  
! bool
! stmt_is_replaceable_p (gimple stmt)
! {
!   return is_replaceable_p (stmt, false);
  }
  
  
--- 360,417 ----
  
  
  /* Return TRUE if expression STMT is suitable for replacement.
!    In addition to ssa_is_replaceable_p, require the same bb, and for -O0
!    same locus and same BLOCK), Considers memory loads as replaceable if aliasing
!    is available.  */
  
  static inline bool
! ter_is_replaceable_p (gimple stmt)
  {
  
!   if (ssa_is_replaceable_p (stmt))
!     {
!       use_operand_p use_p;
!       tree def;
!       gimple use_stmt;
!       location_t locus1, locus2;
!       tree block1, block2;
! 
!       /* Only consider definitions which have a single use.  ssa_is_replaceable_p
! 	 already performed this check, but the use stmt pointer is required for
! 	 further checks.  */
!       def = SINGLE_SSA_TREE_OPERAND (stmt, SSA_OP_DEF);
!       if (!single_imm_use (def, &use_p, &use_stmt))
! 	  return false;
! 
!       /* If the use isn't in this block, it wont be replaced either.  */
!       if (gimple_bb (use_stmt) != gimple_bb (stmt))
!         return false;
! 
!       locus1 = gimple_location (stmt);
!       block1 = LOCATION_BLOCK (locus1);
!       locus1 = LOCATION_LOCUS (locus1);
! 
!       if (gimple_code (use_stmt) == GIMPLE_PHI)
! 	locus2 = gimple_phi_arg_location (use_stmt, 
! 					  PHI_ARG_INDEX_FROM_USE (use_p));
!       else
! 	locus2 = gimple_location (use_stmt);
!       block2 = LOCATION_BLOCK (locus2);
!       locus2 = LOCATION_LOCUS (locus2);
! 
!       if ((!optimize || optimize_debug)
! 	  && ((locus1 != UNKNOWN_LOCATION && locus1 != locus2)
! 	      || (block1 != NULL_TREE && block1 != block2)))
! 	return false;
! 
!       /* Without alias info we can't move around loads.  */
!       if (!optimize && gimple_assign_single_p (stmt)
! 	  && !is_gimple_val (gimple_assign_rhs1 (stmt)))
! 	return false;
  
!       return true;
!     }
!   return false;
  }
  
  
*************** process_replaceable (temp_expr_table_p t
*** 497,503 ****
    ssa_op_iter iter;
    bitmap def_vars, use_vars;
  
!   gcc_checking_assert (is_replaceable_p (stmt, true));
  
    def = SINGLE_SSA_TREE_OPERAND (stmt, SSA_OP_DEF);
    version = SSA_NAME_VERSION (def);
--- 448,454 ----
    ssa_op_iter iter;
    bitmap def_vars, use_vars;
  
!   gcc_checking_assert (ter_is_replaceable_p (stmt));
  
    def = SINGLE_SSA_TREE_OPERAND (stmt, SSA_OP_DEF);
    version = SSA_NAME_VERSION (def);
*************** find_replaceable_in_bb (temp_expr_table_
*** 612,618 ****
        if (is_gimple_debug (stmt))
  	continue;
  
!       stmt_replaceable = is_replaceable_p (stmt, true);
  
        /* Determine if this stmt finishes an existing expression.  */
        FOR_EACH_SSA_TREE_OPERAND (use, stmt, iter, SSA_OP_USE)
--- 563,569 ----
        if (is_gimple_debug (stmt))
  	continue;
  
!       stmt_replaceable = ter_is_replaceable_p (stmt);
  
        /* Determine if this stmt finishes an existing expression.  */
        FOR_EACH_SSA_TREE_OPERAND (use, stmt, iter, SSA_OP_USE)
Index: expr.c
===================================================================
*** expr.c	(revision 202525)
--- expr.c	(working copy)
*************** expand_expr_real_2 (sepops ops, rtx targ
*** 9176,9181 ****
--- 9176,9199 ----
  }
  #undef REDUCE_BIT_FIELD
  
+ 
+ /* Return TRUE if expression STMT is suitable for replacement.  
+    Never consider memory loads as replaceable, because those don't ever lead 
+    into constant expressions.  */
+ 
+ static bool
+ stmt_is_replaceable_p (gimple stmt)
+ {
+   if (ssa_is_replaceable_p (stmt))
+     {
+       /* Don't move around loads.  */
+       if (!gimple_assign_single_p (stmt)
+ 	  || is_gimple_val (gimple_assign_rhs1 (stmt)))
+ 	return true;
+     }
+   return false;
+ }
+ 
  rtx
  expand_expr_real_1 (tree exp, rtx target, enum machine_mode tmode,
  		    enum expand_modifier modifier, rtx *alt_rtl)
Index: tree-ssa-live.h
===================================================================
*** tree-ssa-live.h	(revision 202525)
--- tree-ssa-live.h	(working copy)
*************** make_live_on_entry (tree_live_info_p liv
*** 325,334 ****
  /* From tree-ssa-coalesce.c  */
  extern var_map coalesce_ssa_name (void);
  
- 
- /* From tree-ssa-ter.c  */
- extern bitmap find_replaceable_exprs (var_map);
- extern void dump_replaceable_exprs (FILE *, bitmap);
- 
- 
  #endif /* _TREE_SSA_LIVE_H  */
--- 325,328 ----
Index: tree-ssa-ter.h
===================================================================
*** tree-ssa-ter.h	(revision 0)
--- tree-ssa-ter.h	(working copy)
***************
*** 0 ****
--- 1,26 ----
+ /* Header file for tree-ssa-ter.c exports.
+    Copyright (C) 2013 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 3, 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 COPYING3.  If not see
+ <http://www.gnu.org/licenses/>.  */
+ 
+ #ifndef GCC_TREE_SSA_TER_H
+ #define GCC_TREE_SSA_TER_H
+ 
+ extern bitmap find_replaceable_exprs (var_map);
+ extern void dump_replaceable_exprs (FILE *, bitmap);
+ 
+ #endif /* GCC_TREE_SSA_TER_H */
Index: tree-outof-ssa.c
===================================================================
*** tree-outof-ssa.c	(revision 202525)
--- tree-outof-ssa.c	(working copy)
*************** along with GCC; see the file COPYING3.
*** 31,36 ****
--- 31,37 ----
  #include "dumpfile.h"
  #include "diagnostic-core.h"
  #include "ssaexpand.h"
+ #include "tree-ssa-ter.h"
  
  /* FIXME: A lot of code here deals with expanding to RTL.  All that code
     should be in cfgexpand.c.  */
Index: Makefile.in
===================================================================
*** Makefile.in	(revision 202527)
--- Makefile.in	(working copy)
*************** tree-into-ssa.o : tree-into-ssa.c $(TREE
*** 2309,2315 ****
     $(GIMPLE_H) $(TREE_INLINE_H) $(GIMPLE_PRETTY_PRINT_H)
  tree-ssa-ter.o : tree-ssa-ter.c $(TREE_SSA_H) $(CONFIG_H) $(SYSTEM_H) \
     $(TREE_H) $(DIAGNOSTIC_H) $(TM_H) coretypes.h $(DUMPFILE_H) \
!    $(TREE_SSA_LIVE_H) $(BITMAP_H) $(FLAGS_H) \
     $(GIMPLE_PRETTY_PRINT_H)
  tree-ssa-coalesce.o : tree-ssa-coalesce.c $(TREE_SSA_H) $(CONFIG_H) \
     $(SYSTEM_H) $(TREE_H) $(DIAGNOSTIC_H) $(TM_H) coretypes.h $(DUMPFILE_H) \
--- 2309,2315 ----
     $(GIMPLE_H) $(TREE_INLINE_H) $(GIMPLE_PRETTY_PRINT_H)
  tree-ssa-ter.o : tree-ssa-ter.c $(TREE_SSA_H) $(CONFIG_H) $(SYSTEM_H) \
     $(TREE_H) $(DIAGNOSTIC_H) $(TM_H) coretypes.h $(DUMPFILE_H) \
!    $(TREE_SSA_LIVE_H) $(BITMAP_H) $(FLAGS_H) tree-ssa-ter.h \
     $(GIMPLE_PRETTY_PRINT_H)
  tree-ssa-coalesce.o : tree-ssa-coalesce.c $(TREE_SSA_H) $(CONFIG_H) \
     $(SYSTEM_H) $(TREE_H) $(DIAGNOSTIC_H) $(TM_H) coretypes.h $(DUMPFILE_H) \
*************** tree-ssa-coalesce.o : tree-ssa-coalesce.
*** 2318,2324 ****
  tree-outof-ssa.o : tree-outof-ssa.c $(TREE_SSA_H) $(CONFIG_H) $(SYSTEM_H) \
     $(TREE_H) $(DIAGNOSTIC_H) $(TM_H) coretypes.h $(DUMPFILE_H) \
     $(TREE_SSA_LIVE_H) $(BASIC_BLOCK_H) $(BITMAP_H) $(GGC_H) \
!    $(EXPR_H) $(SSAEXPAND_H) $(GIMPLE_PRETTY_PRINT_H)
  tree-ssa-dse.o : tree-ssa-dse.c $(CONFIG_H) $(SYSTEM_H) coretypes.h \
     $(TM_H) $(GGC_H) $(TREE_H) $(TM_P_H) $(BASIC_BLOCK_H) \
     $(TREE_SSA_H) $(TREE_PASS_H) domwalk.h $(FLAGS_H) \
--- 2318,2324 ----
  tree-outof-ssa.o : tree-outof-ssa.c $(TREE_SSA_H) $(CONFIG_H) $(SYSTEM_H) \
     $(TREE_H) $(DIAGNOSTIC_H) $(TM_H) coretypes.h $(DUMPFILE_H) \
     $(TREE_SSA_LIVE_H) $(BASIC_BLOCK_H) $(BITMAP_H) $(GGC_H) \
!    $(EXPR_H) $(SSAEXPAND_H) $(GIMPLE_PRETTY_PRINT_H) tree-ssa-ter.h
  tree-ssa-dse.o : tree-ssa-dse.c $(CONFIG_H) $(SYSTEM_H) coretypes.h \
     $(TM_H) $(GGC_H) $(TREE_H) $(TM_P_H) $(BASIC_BLOCK_H) \
     $(TREE_SSA_H) $(TREE_PASS_H) domwalk.h $(FLAGS_H) \