/* Create clone of E in the node N represented by CALL_EXPR the callgraph.  */
struct cgraph_edge *
cgraph_clone_edge (struct cgraph_edge *e, struct cgraph_node *n,
		   gimple call_stmt, unsigned stmt_uid, gcov_type count_scale,
		   int freq_scale, bool update_original)
{
  struct cgraph_edge *new_edge;
  gcov_type count = apply_probability (e->count, count_scale);
  gcov_type freq;

  /* We do not want to ignore loop nest after frequency drops to 0.  */
  if (!freq_scale)
    freq_scale = 1;
  freq = e->frequency * (gcov_type) freq_scale / CGRAPH_FREQ_BASE;
  if (freq > CGRAPH_FREQ_MAX)
    freq = CGRAPH_FREQ_MAX;

  if (e->indirect_unknown_callee)
    {
      tree decl;

      if (call_stmt && (decl = gimple_call_fndecl (call_stmt)))
	{
	  struct cgraph_node *callee = cgraph_get_node (decl);
	  gcc_checking_assert (callee);
	  new_edge = cgraph_create_edge (n, callee, call_stmt, count, freq);
	}
      else
	{
	  new_edge = cgraph_create_indirect_edge (n, call_stmt,
						  e->indirect_info->ecf_flags,
						  count, freq);
	  *new_edge->indirect_info = *e->indirect_info;
	}
    }
  else
    {
      new_edge = cgraph_create_edge (n, e->callee, call_stmt, count, freq);
      if (e->indirect_info)
	{
	  new_edge->indirect_info
	    = ggc_alloc_cleared_cgraph_indirect_call_info ();
	  *new_edge->indirect_info = *e->indirect_info;
	}
    }

  new_edge->inline_failed = e->inline_failed;
  new_edge->indirect_inlining_edge = e->indirect_inlining_edge;
  new_edge->lto_stmt_uid = stmt_uid;
  /* Clone flags that depend on call_stmt availability manually.  */
  new_edge->can_throw_external = e->can_throw_external;
  new_edge->call_stmt_cannot_inline_p = e->call_stmt_cannot_inline_p;
  if (update_original)
    {
      e->count -= new_edge->count;
      if (e->count < 0)
	e->count = 0;
    }
  cgraph_call_edge_duplication_hooks (e, new_edge);
  return new_edge;
}
예제 #2
0
static bool
shrink_wrap_one_built_in_call (gimple bi_call)
{
  gimple_stmt_iterator bi_call_bsi;
  basic_block bi_call_bb, join_tgt_bb, guard_bb, guard_bb0;
  edge join_tgt_in_edge_from_call, join_tgt_in_edge_fall_thru;
  edge bi_call_in_edge0, guard_bb_in_edge;
  unsigned tn_cond_stmts, nconds;
  unsigned ci;
  gimple cond_expr = NULL;
  gimple cond_expr_start;
  tree bi_call_label_decl;
  gimple bi_call_label;

  auto_vec<gimple, 12> conds;
  gen_shrink_wrap_conditions (bi_call, conds, &nconds);

  /* This can happen if the condition generator decides
     it is not beneficial to do the transformation.  Just
     return false and do not do any transformation for
     the call.  */
  if (nconds == 0)
    return false;

  bi_call_bb = gimple_bb (bi_call);

  /* Now find the join target bb -- split bi_call_bb if needed.  */
  if (stmt_ends_bb_p (bi_call))
    {
      /* If the call must be the last in the bb, don't split the block,
	 it could e.g. have EH edges.  */
      join_tgt_in_edge_from_call = find_fallthru_edge (bi_call_bb->succs);
      if (join_tgt_in_edge_from_call == NULL)
        return false;
    }
  else
    join_tgt_in_edge_from_call = split_block (bi_call_bb, bi_call);

  bi_call_bsi = gsi_for_stmt (bi_call);

  join_tgt_bb = join_tgt_in_edge_from_call->dest;

  /* Now it is time to insert the first conditional expression
     into bi_call_bb and split this bb so that bi_call is
     shrink-wrapped.  */
  tn_cond_stmts = conds.length ();
  cond_expr = NULL;
  cond_expr_start = conds[0];
  for (ci = 0; ci < tn_cond_stmts; ci++)
    {
      gimple c = conds[ci];
      gcc_assert (c || ci != 0);
      if (!c)
        break;
      gsi_insert_before (&bi_call_bsi, c, GSI_SAME_STMT);
      cond_expr = c;
    }
  nconds--;
  ci++;
  gcc_assert (cond_expr && gimple_code (cond_expr) == GIMPLE_COND);

  /* Now the label.  */
  bi_call_label_decl = create_artificial_label (gimple_location (bi_call));
  bi_call_label = gimple_build_label (bi_call_label_decl);
  gsi_insert_before (&bi_call_bsi, bi_call_label, GSI_SAME_STMT);

  bi_call_in_edge0 = split_block (bi_call_bb, cond_expr);
  bi_call_in_edge0->flags &= ~EDGE_FALLTHRU;
  bi_call_in_edge0->flags |= EDGE_TRUE_VALUE;
  guard_bb0 = bi_call_bb;
  bi_call_bb = bi_call_in_edge0->dest;
  join_tgt_in_edge_fall_thru = make_edge (guard_bb0, join_tgt_bb,
                                          EDGE_FALSE_VALUE);

  bi_call_in_edge0->probability = REG_BR_PROB_BASE * ERR_PROB;
  bi_call_in_edge0->count =
      apply_probability (guard_bb0->count,
			 bi_call_in_edge0->probability);
  join_tgt_in_edge_fall_thru->probability =
      inverse_probability (bi_call_in_edge0->probability);
  join_tgt_in_edge_fall_thru->count =
      guard_bb0->count - bi_call_in_edge0->count;

  /* Code generation for the rest of the conditions  */
  guard_bb = guard_bb0;
  while (nconds > 0)
    {
      unsigned ci0;
      edge bi_call_in_edge;
      gimple_stmt_iterator guard_bsi = gsi_for_stmt (cond_expr_start);
      ci0 = ci;
      cond_expr_start = conds[ci0];
      for (; ci < tn_cond_stmts; ci++)
        {
          gimple c = conds[ci];
          gcc_assert (c || ci != ci0);
          if (!c)
            break;
          gsi_insert_before (&guard_bsi, c, GSI_SAME_STMT);
          cond_expr = c;
        }
      nconds--;
      ci++;
      gcc_assert (cond_expr && gimple_code (cond_expr) == GIMPLE_COND);
      guard_bb_in_edge = split_block (guard_bb, cond_expr);
      guard_bb_in_edge->flags &= ~EDGE_FALLTHRU;
      guard_bb_in_edge->flags |= EDGE_FALSE_VALUE;

      bi_call_in_edge = make_edge (guard_bb, bi_call_bb, EDGE_TRUE_VALUE);

      bi_call_in_edge->probability = REG_BR_PROB_BASE * ERR_PROB;
      bi_call_in_edge->count =
	  apply_probability (guard_bb->count,
			     bi_call_in_edge->probability);
      guard_bb_in_edge->probability =
          inverse_probability (bi_call_in_edge->probability);
      guard_bb_in_edge->count = guard_bb->count - bi_call_in_edge->count;
    }

  if (dump_file && (dump_flags & TDF_DETAILS))
    {
      location_t loc;
      loc = gimple_location (bi_call);
      fprintf (dump_file,
               "%s:%d: note: function call is shrink-wrapped"
               " into error conditions.\n",
               LOCATION_FILE (loc), LOCATION_LINE (loc));
    }

  return true;
}
예제 #3
0
파일: loop-unswitch.c 프로젝트: Zekom/gcc
static struct loop *
unswitch_loop (struct loop *loop, basic_block unswitch_on, rtx cond, rtx cinsn)
{
  edge entry, latch_edge, true_edge, false_edge, e;
  basic_block switch_bb, unswitch_on_alt;
  struct loop *nloop;
  int irred_flag, prob;
  rtx seq;

  /* Some sanity checking.  */
  gcc_assert (flow_bb_inside_loop_p (loop, unswitch_on));
  gcc_assert (EDGE_COUNT (unswitch_on->succs) == 2);
  gcc_assert (just_once_each_iteration_p (loop, unswitch_on));
  gcc_assert (!loop->inner);
  gcc_assert (flow_bb_inside_loop_p (loop, EDGE_SUCC (unswitch_on, 0)->dest));
  gcc_assert (flow_bb_inside_loop_p (loop, EDGE_SUCC (unswitch_on, 1)->dest));

  entry = loop_preheader_edge (loop);

  /* Make a copy.  */
  irred_flag = entry->flags & EDGE_IRREDUCIBLE_LOOP;
  entry->flags &= ~EDGE_IRREDUCIBLE_LOOP;
  if (!duplicate_loop_to_header_edge (loop, entry, 1,
			      	      NULL, NULL, NULL, 0))
    return NULL;
  entry->flags |= irred_flag;

  /* Record the block with condition we unswitch on.  */
  unswitch_on_alt = get_bb_copy (unswitch_on);
  true_edge = BRANCH_EDGE (unswitch_on_alt);
  false_edge = FALLTHRU_EDGE (unswitch_on);
  latch_edge = single_succ_edge (get_bb_copy (loop->latch));

  /* Create a block with the condition.  */
  prob = true_edge->probability;
  switch_bb = create_empty_bb (EXIT_BLOCK_PTR->prev_bb);
  seq = compare_and_jump_seq (XEXP (cond, 0), XEXP (cond, 1), GET_CODE (cond),
			      block_label (true_edge->dest),
			      prob, cinsn);
  emit_insn_after (seq, BB_END (switch_bb));
  e = make_edge (switch_bb, true_edge->dest, 0);
  e->probability = prob;
  e->count = apply_probability (latch_edge->count, prob);
  e = make_edge (switch_bb, FALLTHRU_EDGE (unswitch_on)->dest, EDGE_FALLTHRU);
  e->probability = false_edge->probability;
  e->count = apply_probability (latch_edge->count, false_edge->probability);

  if (irred_flag)
    {
      switch_bb->flags |= BB_IRREDUCIBLE_LOOP;
      EDGE_SUCC (switch_bb, 0)->flags |= EDGE_IRREDUCIBLE_LOOP;
      EDGE_SUCC (switch_bb, 1)->flags |= EDGE_IRREDUCIBLE_LOOP;
    }
  else
    {
      switch_bb->flags &= ~BB_IRREDUCIBLE_LOOP;
      EDGE_SUCC (switch_bb, 0)->flags &= ~EDGE_IRREDUCIBLE_LOOP;
      EDGE_SUCC (switch_bb, 1)->flags &= ~EDGE_IRREDUCIBLE_LOOP;
    }

  /* Loopify from the copy of LOOP body, constructing the new loop.  */
  nloop = loopify (latch_edge,
		   single_pred_edge (get_bb_copy (loop->header)), switch_bb,
		   BRANCH_EDGE (switch_bb), FALLTHRU_EDGE (switch_bb), true,
		   prob, REG_BR_PROB_BASE - prob);

  copy_loop_info (loop, nloop);
  /* Remove branches that are now unreachable in new loops.  */
  remove_path (true_edge);
  remove_path (false_edge);

  /* Preserve the simple loop preheaders.  */
  split_edge (loop_preheader_edge (loop));
  split_edge (loop_preheader_edge (nloop));

  return nloop;
}