[PATCH][9/n] tree LIM TLC

[Richard Biener <rguenther at suse dot de>]

This makes the linked list of dependent stmts a vector instead.
Saves separate allocation / free of list entries and overall
some memory (overhead for vecs is less than 50%).

Bootstrap and regtest on x86_64-unknown-linux-gnu running.

Richard.

2013-03-13  Richard Biener  <rguenther@suse.de>

	* tree-ssa-loop-im.c (struct depend): Remove.
	(struct lim_aux_data): Make depends a vec of gimples.
	(free_lim_aux_data): Adjust.
	(add_dependency): Likewise.
	(set_level): Likewise.

Index: trunk/gcc/tree-ssa-loop-im.c
===================================================================
*** trunk.orig/gcc/tree-ssa-loop-im.c	2013-03-13 14:19:17.000000000 +0100
--- trunk/gcc/tree-ssa-loop-im.c	2013-03-13 15:38:55.835709837 +0100
*************** along with GCC; see the file COPYING3.
*** 58,72 ****
  	 something;
       }  */
  
- /* A type for the list of statements that have to be moved in order to be able
-    to hoist an invariant computation.  */
- 
- struct depend
- {
-   gimple stmt;
-   struct depend *next;
- };
- 
  /* The auxiliary data kept for each statement.  */
  
  struct lim_aux_data
--- 58,63 ----
*************** struct lim_aux_data
*** 85,95 ****
    unsigned cost;		/* Cost of the computation performed by the
  				   statement.  */
  
!   struct depend *depends;	/* List of statements that must be also hoisted
! 				   out of the loop when this statement is
! 				   hoisted; i.e. those that define the operands
! 				   of the statement and are inside of the
! 				   MAX_LOOP loop.  */
  };
  
  /* Maps statements to their lim_aux_data.  */
--- 76,86 ----
    unsigned cost;		/* Cost of the computation performed by the
  				   statement.  */
  
!   vec<gimple> depends;		/* Vector of statements that must be also
! 				   hoisted out of the loop when this statement
! 				   is hoisted; i.e. those that define the
! 				   operands of the statement and are inside of
! 				   the MAX_LOOP loop.  */
  };
  
  /* Maps statements to their lim_aux_data.  */
*************** get_lim_data (gimple stmt)
*** 204,216 ****
  static void
  free_lim_aux_data (struct lim_aux_data *data)
  {
!   struct depend *dep, *next;
! 
!   for (dep = data->depends; dep; dep = next)
!     {
!       next = dep->next;
!       free (dep);
!     }
    free (data);
  }
  
--- 195,201 ----
  static void
  free_lim_aux_data (struct lim_aux_data *data)
  {
!   data->depends.release();
    free (data);
  }
  
*************** add_dependency (tree def, struct lim_aux
*** 475,481 ****
    gimple def_stmt = SSA_NAME_DEF_STMT (def);
    basic_block def_bb = gimple_bb (def_stmt);
    struct loop *max_loop;
-   struct depend *dep;
    struct lim_aux_data *def_data;
  
    if (!def_bb)
--- 460,465 ----
*************** add_dependency (tree def, struct lim_aux
*** 500,509 ****
        && def_bb->loop_father == loop)
      data->cost += def_data->cost;
  
!   dep = XNEW (struct depend);
!   dep->stmt = def_stmt;
!   dep->next = data->depends;
!   data->depends = dep;
  
    return true;
  }
--- 484,490 ----
        && def_bb->loop_father == loop)
      data->cost += def_data->cost;
  
!   data->depends.safe_push (def_stmt);
  
    return true;
  }
*************** static void
*** 866,873 ****
  set_level (gimple stmt, struct loop *orig_loop, struct loop *level)
  {
    struct loop *stmt_loop = gimple_bb (stmt)->loop_father;
-   struct depend *dep;
    struct lim_aux_data *lim_data;
  
    stmt_loop = find_common_loop (orig_loop, stmt_loop);
    lim_data = get_lim_data (stmt);
--- 847,855 ----
  set_level (gimple stmt, struct loop *orig_loop, struct loop *level)
  {
    struct loop *stmt_loop = gimple_bb (stmt)->loop_father;
    struct lim_aux_data *lim_data;
+   gimple dep_stmt;
+   unsigned i;
  
    stmt_loop = find_common_loop (orig_loop, stmt_loop);
    lim_data = get_lim_data (stmt);
*************** set_level (gimple stmt, struct loop *ori
*** 881,888 ****
  	      || flow_loop_nested_p (lim_data->max_loop, level));
  
    lim_data->tgt_loop = level;
!   for (dep = lim_data->depends; dep; dep = dep->next)
!     set_level (dep->stmt, orig_loop, level);
  }
  
  /* Determines an outermost loop from that we want to hoist the statement STMT.
--- 863,870 ----
  	      || flow_loop_nested_p (lim_data->max_loop, level));
  
    lim_data->tgt_loop = level;
!   FOR_EACH_VEC_ELT (lim_data->depends, i, dep_stmt)
!     set_level (dep_stmt, orig_loop, level);
  }
  
  /* Determines an outermost loop from that we want to hoist the statement STMT.