[1/2] tree-ssa-strlen optimization pass

Hi!

Here is an updated version of the support patch for the tree-ssa-strlen.c
optimization.  The only change is the propagation of gimple_block
to the new call from the old call, otherwise Wobjsize-1.c testcase
fails when we optimize that __strcpy_chk into __memcpy_chk, but don't
propagate its BLOCK.  Perhaps gimplify_and_update_call_from_tree and
update_call_from_tree should do it as well, for all the statements without
gimple_block it creates (can do that as a follow-up).

Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?

2011-09-15  Jakub Jelinek  <jakub@redhat.com>

	* gimple-fold.c (gimplify_and_update_call_from_tree): Set
	gctx.into_ssa after push_gimplify_context.

	* gimple.c (gimple_build_call_valist): New function.
	* gimple.h (gimple_build_call_valist): New prototype.
	* tree-ssa-propagate.c (finish_update_gimple_call): New function.
	(update_gimple_call): Likewise.
	(update_call_from_tree): Use finish_update_gimple_call.
	* tree-ssa-propagate.h (update_gimple_call): New prototype.


	Jakub

On Thu, Sep 15, 2011 at 7:00 PM, Jakub Jelinek <jakub@redhat.com> wrote:
> Hi!
>
> Here is an updated version of the support patch for the tree-ssa-strlen.c
> optimization.  The only change is the propagation of gimple_block
> to the new call from the old call, otherwise Wobjsize-1.c testcase
> fails when we optimize that __strcpy_chk into __memcpy_chk, but don't
> propagate its BLOCK.  Perhaps gimplify_and_update_call_from_tree and
> update_call_from_tree should do it as well, for all the statements without
> gimple_block it creates (can do that as a follow-up).

Yeah, I think so.

> Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?

Ok.

Thanks,
Richard.

> 2011-09-15  Jakub Jelinek  <jakub@redhat.com>
>
>        * gimple-fold.c (gimplify_and_update_call_from_tree): Set
>        gctx.into_ssa after push_gimplify_context.
>
>        * gimple.c (gimple_build_call_valist): New function.
>        * gimple.h (gimple_build_call_valist): New prototype.
>        * tree-ssa-propagate.c (finish_update_gimple_call): New function.
>        (update_gimple_call): Likewise.
>        (update_call_from_tree): Use finish_update_gimple_call.
>        * tree-ssa-propagate.h (update_gimple_call): New prototype.
>
> --- gcc/gimple-fold.c.jj        2011-09-15 12:18:54.000000000 +0200
> +++ gcc/gimple-fold.c   2011-09-15 12:23:58.000000000 +0200
> @@ -551,6 +551,7 @@ gimplify_and_update_call_from_tree (gimp
>   reaching_vuse = gimple_vuse (stmt);
>
>   push_gimplify_context (&gctx);
> +  gctx.into_ssa = gimple_in_ssa_p (cfun);
>
>   if (lhs == NULL_TREE)
>     {
> --- gcc/gimple.c.jj     2011-09-15 12:18:37.000000000 +0200
> +++ gcc/gimple.c        2011-09-15 12:23:58.000000000 +0200
> @@ -215,9 +215,10 @@ gimple_call_reset_alias_info (gimple s)
>     pt_solution_reset (gimple_call_clobber_set (s));
>  }
>
> -/* Helper for gimple_build_call, gimple_build_call_vec and
> -   gimple_build_call_from_tree.  Build the basic components of a
> -   GIMPLE_CALL statement to function FN with NARGS arguments.  */
> +/* Helper for gimple_build_call, gimple_build_call_valist,
> +   gimple_build_call_vec and gimple_build_call_from_tree.  Build the basic
> +   components of a GIMPLE_CALL statement to function FN with NARGS
> +   arguments.  */
>
>  static inline gimple
>  gimple_build_call_1 (tree fn, unsigned nargs)
> @@ -272,6 +273,26 @@ gimple_build_call (tree fn, unsigned nar
>  }
>
>
> +/* Build a GIMPLE_CALL statement to function FN.  NARGS is the number of
> +   arguments.  AP contains the arguments.  */
> +
> +gimple
> +gimple_build_call_valist (tree fn, unsigned nargs, va_list ap)
> +{
> +  gimple call;
> +  unsigned i;
> +
> +  gcc_assert (TREE_CODE (fn) == FUNCTION_DECL || is_gimple_call_addr (fn));
> +
> +  call = gimple_build_call_1 (fn, nargs);
> +
> +  for (i = 0; i < nargs; i++)
> +    gimple_call_set_arg (call, i, va_arg (ap, tree));
> +
> +  return call;
> +}
> +
> +
>  /* Helper for gimple_build_call_internal and gimple_build_call_internal_vec.
>    Build the basic components of a GIMPLE_CALL statement to internal
>    function FN with NARGS arguments.  */
> --- gcc/gimple.h.jj     2011-09-15 12:18:54.000000000 +0200
> +++ gcc/gimple.h        2011-09-15 12:23:58.000000000 +0200
> @@ -831,6 +831,7 @@ gimple gimple_build_debug_source_bind_st
>
>  gimple gimple_build_call_vec (tree, VEC(tree, heap) *);
>  gimple gimple_build_call (tree, unsigned, ...);
> +gimple gimple_build_call_valist (tree, unsigned, va_list);
>  gimple gimple_build_call_internal (enum internal_fn, unsigned, ...);
>  gimple gimple_build_call_internal_vec (enum internal_fn, VEC(tree, heap) *);
>  gimple gimple_build_call_from_tree (tree);
> --- gcc/tree-ssa-propagate.c.jj 2011-09-15 12:18:37.000000000 +0200
> +++ gcc/tree-ssa-propagate.c    2011-09-15 16:46:54.000000000 +0200
> @@ -1,5 +1,5 @@
>  /* Generic SSA value propagation engine.
> -   Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010
> +   Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011
>    Free Software Foundation, Inc.
>    Contributed by Diego Novillo <dnovillo@redhat.com>
>
> @@ -673,6 +673,40 @@ move_ssa_defining_stmt_for_defs (gimple
>     }
>  }
>
> +/* Helper function for update_gimple_call and update_call_from_tree.
> +   A GIMPLE_CALL STMT is being replaced with GIMPLE_CALL NEW_STMT.  */
> +
> +static void
> +finish_update_gimple_call (gimple_stmt_iterator *si_p, gimple new_stmt,
> +                          gimple stmt)
> +{
> +  gimple_call_set_lhs (new_stmt, gimple_call_lhs (stmt));
> +  move_ssa_defining_stmt_for_defs (new_stmt, stmt);
> +  gimple_set_vuse (new_stmt, gimple_vuse (stmt));
> +  gimple_set_vdef (new_stmt, gimple_vdef (stmt));
> +  gimple_set_location (new_stmt, gimple_location (stmt));
> +  if (gimple_block (new_stmt) == NULL_TREE)
> +    gimple_set_block (new_stmt, gimple_block (stmt));
> +  gsi_replace (si_p, new_stmt, false);
> +}
> +
> +/* Update a GIMPLE_CALL statement at iterator *SI_P to call to FN
> +   with number of arguments NARGS, where the arguments in GIMPLE form
> +   follow NARGS argument.  */
> +
> +bool
> +update_gimple_call (gimple_stmt_iterator *si_p, tree fn, int nargs, ...)
> +{
> +  va_list ap;
> +  gimple new_stmt, stmt = gsi_stmt (*si_p);
> +
> +  gcc_assert (is_gimple_call (stmt));
> +  va_start (ap, nargs);
> +  new_stmt = gimple_build_call_valist (fn, nargs, ap);
> +  finish_update_gimple_call (si_p, new_stmt, stmt);
> +  va_end (ap);
> +  return true;
> +}
>
>  /* Update a GIMPLE_CALL statement at iterator *SI_P to reflect the
>    value of EXPR, which is expected to be the result of folding the
> @@ -689,14 +723,8 @@ move_ssa_defining_stmt_for_defs (gimple
>  bool
>  update_call_from_tree (gimple_stmt_iterator *si_p, tree expr)
>  {
> -  tree lhs;
> -
>   gimple stmt = gsi_stmt (*si_p);
>
> -  gcc_assert (is_gimple_call (stmt));
> -
> -  lhs = gimple_call_lhs (stmt);
> -
>   if (valid_gimple_call_p (expr))
>     {
>       /* The call has simplified to another call.  */
> @@ -716,18 +744,14 @@ update_call_from_tree (gimple_stmt_itera
>         }
>
>       new_stmt = gimple_build_call_vec (fn, args);
> -      gimple_call_set_lhs (new_stmt, lhs);
> -      move_ssa_defining_stmt_for_defs (new_stmt, stmt);
> -      gimple_set_vuse (new_stmt, gimple_vuse (stmt));
> -      gimple_set_vdef (new_stmt, gimple_vdef (stmt));
> -      gimple_set_location (new_stmt, gimple_location (stmt));
> -      gsi_replace (si_p, new_stmt, false);
> +      finish_update_gimple_call (si_p, new_stmt, stmt);
>       VEC_free (tree, heap, args);
>
>       return true;
>     }
>   else if (valid_gimple_rhs_p (expr))
>     {
> +      tree lhs = gimple_call_lhs (stmt);
>       gimple new_stmt;
>
>       /* The call has simplified to an expression
> --- gcc/tree-ssa-propagate.h.jj 2011-09-15 12:18:37.000000000 +0200
> +++ gcc/tree-ssa-propagate.h    2011-09-15 12:23:58.000000000 +0200
> @@ -1,6 +1,7 @@
>  /* Data structures and function declarations for the SSA value propagation
>    engine.
> -   Copyright (C) 2004, 2005, 2007, 2008, 2010 Free Software Foundation, Inc.
> +   Copyright (C) 2004, 2005, 2007, 2008, 2010, 2011
> +   Free Software Foundation, Inc.
>    Contributed by Diego Novillo <dnovillo@redhat.com>
>
>  This file is part of GCC.
> @@ -72,6 +73,7 @@ typedef tree (*ssa_prop_get_value_fn) (t
>  void ssa_propagate (ssa_prop_visit_stmt_fn, ssa_prop_visit_phi_fn);
>  bool valid_gimple_rhs_p (tree);
>  void move_ssa_defining_stmt_for_defs (gimple, gimple);
> +bool update_gimple_call (gimple_stmt_iterator *, tree, int, ...);
>  bool update_call_from_tree (gimple_stmt_iterator *, tree);
>  bool stmt_makes_single_store (gimple);
>  bool substitute_and_fold (ssa_prop_get_value_fn, ssa_prop_fold_stmt_fn, bool);
>
>        Jakub
>