besched.c

#ifdef HAVE_CONFIG_H
# include "config.h"
#endif

#ifdef HAVE_STDLIB_H
# include <stdlib.h>
#endif

#include "impl.h"
#include "irprintf.h"
#include "irgwalk.h"
#include "irnode_t.h"
#include "irgraph_t.h"
#include "iredges_t.h"
#include "debug.h"

#include "bearch.h"
#include "besched_t.h"
#include "beutil.h"
#include "belistsched.h"

FIRM_IMPL1(sched_get_time_step, int, const ir_node *)
FIRM_IMPL1(sched_has_next, int, const ir_node *)
FIRM_IMPL1(sched_has_prev, int, const ir_node *)
FIRM_IMPL1(sched_next, ir_node *, const ir_node *)
FIRM_IMPL1(sched_prev, ir_node *, const ir_node *)
FIRM_IMPL1(sched_first, ir_node *, const ir_node *)
FIRM_IMPL1(sched_last, ir_node *, const ir_node *)
FIRM_IMPL2(sched_add_after, ir_node *, ir_node *, ir_node *)
FIRM_IMPL2(sched_add_before, ir_node *, ir_node *, ir_node *)
FIRM_IMPL2(sched_comes_after, int, const ir_node *, const ir_node *)
FIRM_IMPL1_VOID(sched_remove, ir_node *)

size_t sched_irn_data_offset = 0;

static void block_sched_dumper(ir_node *block, void *env)
{
	FILE *f = env;
	const ir_node *curr;

	ir_fprintf(f, "%+F:\n", block);
	sched_foreach(block, curr) {
    sched_info_t *info = get_irn_sched_info(curr);
		ir_fprintf(f, "\t%6d: %+F\n", info->time_step, curr);
	}
}

void be_sched_dump(FILE *f, ir_graph *irg)
{
	irg_block_walk_graph(irg, block_sched_dumper, NULL, f);
}

/* Init the scheduling stuff. */
void be_sched_init(void)
{
	sched_irn_data_offset = register_additional_node_data(sizeof(sched_info_t));
}

void sched_renumber(const ir_node *block)
{
  ir_node *irn;
  sched_info_t *inf;
  sched_timestep_t step = 0;

  sched_foreach(block, irn) {
    inf = get_irn_sched_info(irn);
    inf->time_step = step;
    step += SCHED_INITIAL_GRANULARITY;
  }
}

/* Verify a schedule. */
int sched_verify(const ir_node *block)
{
  int res = 1;
  const ir_node *irn;
  int i, n;
  int *save_time_step;
  const ir_node **save_nodes;
  const ir_edge_t *edge;
  pset *scheduled_nodes = pset_new_ptr_default();
  FIRM_DBG_REGISTER(firm_dbg_module_t *dbg_sched, "firm.be.sched");

  /* Count the number of nodes in the schedule. */
  n = 0;
  sched_foreach(block, irn)
    n++;

  if(n <= 0)
    return 1;

  save_time_step = xmalloc(n * sizeof(save_time_step[0]));
  save_nodes = xmalloc(n * sizeof(save_nodes[0]));

  i = 0;
  sched_foreach(block, irn) {
    sched_info_t *info = get_irn_sched_info(irn);
    save_time_step[i] = info->time_step;
    save_nodes[i] = (ir_node *)irn;
    info->time_step = i;
    pset_insert_ptr(scheduled_nodes, irn);

    i += 1;
  }

  /*
   * Check if each relevant operand of a node is scheduled before
   * the node itself.
   */
  sched_foreach(block, irn) {
    int i, n;
    int step = sched_get_time_step(irn);

    for(i = 0, n = get_irn_arity(irn); i < n; i++) {
      ir_node *op = get_irn_n(irn, i);

      if(to_appear_in_schedule(op)
          && !is_Phi(irn)
          && get_nodes_block(op) == block
          && sched_get_time_step(op) > step) {

          DBG((dbg_sched, LEVEL_DEFAULT,
                "%+F: %+F is operand of %+F but scheduled after\n", block, op, irn));
          res = 0;
      }
    }
  }

  /* Check, if the time steps are correct */
  for(i = 1; i < n; ++i) {
    if(save_time_step[i] - save_time_step[i - 1] <= 0) {
      DBG((dbg_sched, LEVEL_DEFAULT,
            "%+F from %+F(%d) -> %+F(%d) step shrinks from %d -> %d\n",
            block, save_nodes[i - 1], i - 1, save_nodes[i], i,
            save_time_step[i - 1], save_time_step[i]));
      res = 0;
    }
  }

  /* Restore the old time steps */
  i = 0;
  sched_foreach(block, irn) {
    sched_info_t *info = get_irn_sched_info(irn);
    info->time_step = save_time_step[i++];
  }

  /* Check for all nodes in the block if they are scheduled. */
  foreach_out_edge(block, edge) {
    ir_node *irn = get_edge_src_irn(edge);
    if(to_appear_in_schedule(irn) && !pset_find_ptr(scheduled_nodes, irn))
      DBG((dbg_sched, LEVEL_DEFAULT,
            "%+F: %+F is in block but not scheduled\n", block, irn));
  }

  del_pset(scheduled_nodes);
  free(save_time_step);
  free((void *) save_nodes);
  return res;
}

/**
 * Block-Walker: verify the current block and update the status
 */
static void sched_verify_walker(ir_node *block, void *data)
{
  int *res = data;
  *res &= sched_verify(block);
}

/* Verify the schedules in all blocks of the irg. */
int sched_verify_irg(ir_graph *irg)
{
  int res = 1;
  irg_block_walk_graph(irg, sched_verify_walker, NULL, &res);

  return res;
}

int sched_skip_cf_predicator(const ir_node *irn, void *data) {
  arch_env_t *ae = data;
  return arch_irn_classify(ae, irn) == arch_irn_class_branch;
}

int sched_skip_phi_predicator(const ir_node *irn, void *data) {
	return is_Phi(irn);
}

/* Skip nodes in a schedule. */
ir_node *sched_skip(ir_node *from, int forward, sched_predicator_t *predicator, void *data)
{
	const ir_node *bl = get_block(from);
	ir_node *curr;

	if (is_Block(from))
		from = forward ? sched_next(from) : sched_prev(from);

	for(curr = from; curr != bl && predicator(curr, data); curr = forward ? sched_next(curr) : sched_prev(curr));

	return curr;
}

/** A simple forward single linked list. */
typedef struct {
	ir_node *start;   /**< start of the list */
	ir_node *end;     /**< last block in the list */
	unsigned n_blks;  /**< number of blocks in the list */
} anchor;

/**
 * Ext-Block walker: create a block schedule
 */
static void create_block_list(ir_extblk *blk, void *env) {
	anchor *list = env;
	int i, n;

	for (i = 0, n = get_extbb_n_blocks(blk); i < n; ++i) {
		ir_node *block = get_extbb_block(blk, i);

		set_irn_link(block, NULL);
		if (list->start)
			set_irn_link(list->end, block);
		else
			list->start = block;

		list->end = block;
		++list->n_blks;
	}
}

/*
 * Calculates a block schedule. The schedule is stored as a linked
 * list starting at the start_block of the irg.
 */
ir_node **sched_create_block_schedule(ir_graph *irg)
{
	anchor list;
	ir_node **blk_list, *b, *n;
	unsigned i;

	/* schedule extended basic blocks */
	compute_extbb(irg);

	list.start  = NULL;
	list.end    = NULL;
	list.n_blks = 0;
	irg_extblock_walk_graph(irg, NULL, create_block_list, &list);

	/** create an array, so we can go forward and backward */
	blk_list = NEW_ARR_D(ir_node *, irg->obst,list.n_blks);

	for (i = 0, b = list.start; b; b = n, ++i) {
		n = get_irn_link(b);
		set_irn_link(b, INT_TO_PTR(i));

		blk_list[i] = b;
	}
	return blk_list;
}