Re: [PATCH][dbgcnt] New debug counter global_alloc_at_func, global_alloc_at_reg, and make sched_insn work

[Kenneth Zadeck <zadeck at naturalbridge dot com>]

Seongbae Park (???, ???) wrote:
> It has already bootstrapped on ia64.
> I'm running the bootstrap & regtest on x86-64.
> This is for debugging and should not affect the code correctness
> unless enabled.
> Ok if all tests pass ?
>
> 2007-06-18 Seongbea Park <seongbae.park@gmail.com>
> Maxim Kuvyrkov <mkuvyrkov@ispras.ru>
>
> * dbgcnt.def (global_alloc_at_func, global_alloc_at_reg):
> New counters.
> * haifa-sched.c (queue_to_ready): Pick the next insn if
> dbgcnt(sched_insn) reaches the limit.
> (choose_ready): New parameter INSN_PTR and new return value.
> (schedule_block): Handle dbgcnt(sched_insn). Handle
> the new return value from choose_ready.
> * global.c (global_aloc): New dbgcnt global_alloc_at_reg.
> (rest_of_handle_global_alloc): New global_alloc_at_func.
>
>
Yes, this is fine.

Kenny

> ------------------------------------------------------------------------
>
> Index: gcc/dbgcnt.def
> ===================================================================
> --- gcc/dbgcnt.def	(revision 125828)
> +++ gcc/dbgcnt.def	(working copy)
> @@ -82,3 +82,5 @@ DEBUG_COUNTER (sched_insn)
>  DEBUG_COUNTER (sched_region)
>  DEBUG_COUNTER (split_for_sched2)
>  DEBUG_COUNTER (tail_call)
> +DEBUG_COUNTER (global_alloc_at_func)
> +DEBUG_COUNTER (global_alloc_at_reg)
> Index: gcc/haifa-sched.c
> ===================================================================
> --- gcc/haifa-sched.c	(revision 125828)
> +++ gcc/haifa-sched.c	(working copy)
> @@ -539,7 +539,7 @@ static rtx ready_remove (struct ready_li
>  static void ready_remove_insn (rtx);
>  static int max_issue (struct ready_list *, int *, int);
>  
> -static rtx choose_ready (struct ready_list *);
> +static int choose_ready (struct ready_list *, rtx *);
>  
>  static void fix_inter_tick (rtx, rtx);
>  static int fix_tick_ready (rtx);
> @@ -1483,9 +1483,17 @@ queue_to_ready (struct ready_list *ready
>  {
>    rtx insn;
>    rtx link;
> +  rtx skip_insn;
>  
>    q_ptr = NEXT_Q (q_ptr);
>  
> +  if (dbg_cnt (sched_insn) == false)
> +    /* If debug counter is activated do not requeue insn next after
> +       last_scheduled_insn.  */
> +    skip_insn = next_nonnote_insn (last_scheduled_insn);
> +  else
> +    skip_insn = NULL_RTX;
> +
>    /* Add all pending insns that can be scheduled without stalls to the
>       ready list.  */
>    for (link = insn_queue[q_ptr]; link; link = XEXP (link, 1))
> @@ -1501,7 +1509,8 @@ queue_to_ready (struct ready_list *ready
>  	 See the comment in schedule_block for the rationale.  */
>        if (!reload_completed
>  	  && ready->n_ready > MAX_SCHED_READY_INSNS
> -	  && !SCHED_GROUP_P (insn))
> +	  && !SCHED_GROUP_P (insn)
> +	  && insn != skip_insn)
>  	{
>  	  if (sched_verbose >= 2)
>  	    fprintf (sched_dump, "requeued because ready full\n");
> @@ -1980,17 +1989,43 @@ max_issue (struct ready_list *ready, int
>  
>  /* The following function chooses insn from READY and modifies
>     *N_READY and READY.  The following function is used only for first
> -   cycle multipass scheduling.  */
> -
> -static rtx
> -choose_ready (struct ready_list *ready)
> +   cycle multipass scheduling.
> +   Return:
> +   -1 if cycle should be advanced,
> +   0 if INSN_PTR is set to point to the desirable insn,
> +   1 if choose_ready () should be restarted without advancing the cycle.  */
> +static int
> +choose_ready (struct ready_list *ready, rtx *insn_ptr)
>  {
> -  int lookahead = 0;
> +  int lookahead;
> +
> +  if (dbg_cnt (sched_insn) == false)
> +    {
> +      rtx insn;
> +
> +      insn = next_nonnote_insn (last_scheduled_insn);
> +
> +      if (QUEUE_INDEX (insn) == QUEUE_READY)
> +	/* INSN is in the ready_list.  */
> +	{
> +	  ready_remove_insn (insn);
> +	  *insn_ptr = insn;
> +	  return 0;
> +	}
> +
> +      /* INSN is in the queue.  Advance cycle to move it to the ready list.  */
> +      return -1;
> +    }
> +
> +  lookahead = 0;
>  
>    if (targetm.sched.first_cycle_multipass_dfa_lookahead)
>      lookahead = targetm.sched.first_cycle_multipass_dfa_lookahead ();
>    if (lookahead <= 0 || SCHED_GROUP_P (ready_element (ready, 0)))
> -    return ready_remove_first (ready);
> +    {
> +      *insn_ptr = ready_remove_first (ready);
> +      return 0;
> +    }
>    else
>      {
>        /* Try to choose the better insn.  */
> @@ -2007,7 +2042,10 @@ choose_ready (struct ready_list *ready)
>  	}
>        insn = ready_element (ready, 0);
>        if (INSN_CODE (insn) < 0)
> -	return ready_remove_first (ready);
> +	{
> +	  *insn_ptr = ready_remove_first (ready);
> +	  return 0;
> +	}
>  
>        if (spec_info
>  	  && spec_info->flags & (PREFER_NON_DATA_SPEC
> @@ -2049,7 +2087,7 @@ choose_ready (struct ready_list *ready)
>  	   list.  */
>  	{
>  	  change_queue_index (insn, 1);
> -	  return 0;
> +	  return 1;
>  	}
>  
>        max_points = ISSUE_POINTS (insn);
> @@ -2071,9 +2109,15 @@ choose_ready (struct ready_list *ready)
>  	}
>  
>        if (max_issue (ready, &index, max_points) == 0)
> -	return ready_remove_first (ready);
> +	{
> +	  *insn_ptr = ready_remove_first (ready);
> +	  return 0;
> +	}
>        else
> -	return ready_remove (ready, index);
> +	{
> +	  *insn_ptr = ready_remove (ready, index);
> +	  return 0;
> +	}
>      }
>  }
>  
> @@ -2172,9 +2216,27 @@ schedule_block (basic_block *target_bb, 
>  		   ";;\t\t before reload => truncated to %d insns\n", i);
>  	}
>  
> -      /* Delay all insns past it for 1 cycle.  */
> -      while (i < ready.n_ready)
> -	queue_insn (ready_remove (&ready, i), 1);
> +      /* Delay all insns past it for 1 cycle.  If debug counter is
> +	 activated make an exception for the insn right after
> +	 last_scheduled_insn.  */
> +      {
> +	rtx skip_insn;
> +
> +	if (dbg_cnt (sched_insn) == false)
> +	  skip_insn = next_nonnote_insn (last_scheduled_insn);
> +	else
> +	  skip_insn = NULL_RTX;
> +
> +	while (i < ready.n_ready)
> +	  {
> +	    rtx insn;
> +
> +	    insn = ready_remove (&ready, i);
> +
> +	    if (insn != skip_insn)
> +	      queue_insn (insn, 1);
> +	  }
> +      }
>      }
>  
>    /* Now we can restore basic block notes and maintain precise cfg.  */
> @@ -2271,29 +2333,22 @@ schedule_block (basic_block *target_bb, 
>  	      || !(*current_sched_info->schedule_more_p) ())
>  	    break;
>  
> -          if (dbg_cnt (sched_insn) == false)
> -            {
> -              insn = NEXT_INSN (last_scheduled_insn); 
> -              while ((*current_sched_info->schedule_more_p) ())
> -                {
> -                  (*current_sched_info->begin_schedule_ready) (insn,
> -                                                               last_scheduled_insn);
> -                  if (QUEUE_INDEX (insn) >= 0)
> -                    queue_remove (insn);
> -                  last_scheduled_insn = insn;
> -                  insn = NEXT_INSN (insn);
> -                }
> -              while (ready.n_ready)
> -                ready_remove_first (&ready);
> -              goto bail_out;
> -            }
> -
>  	  /* Select and remove the insn from the ready list.  */
>  	  if (sort_p)
>  	    {
> -	      insn = choose_ready (&ready);
> -	      if (!insn)
> +	      int res;
> +
> +	      insn = NULL_RTX;
> +	      res = choose_ready (&ready, &insn);
> +
> +	      if (res < 0)
> +		/* Finish cycle.  */
> +		break;
> +	      if (res > 0)
> +		/* Restart choose_ready ().  */
>  		continue;
> +
> +	      gcc_assert (insn != NULL_RTX);
>  	    }
>  	  else
>  	    insn = ready_remove_first (&ready);
> @@ -2445,7 +2500,6 @@ schedule_block (basic_block *target_bb, 
>  	}
>      }
>  
> -bail_out:
>    /* Debug info.  */
>    if (sched_verbose)
>      {
> Index: gcc/global.c
> ===================================================================
> --- gcc/global.c	(revision 125828)
> +++ gcc/global.c	(working copy)
> @@ -41,6 +41,7 @@ Software Foundation, 51 Franklin Street,
>  #include "timevar.h"
>  #include "df.h"
>  #include "vecprim.h"
> +#include "dbgcnt.h"
>  
>  /* This pass of the compiler performs global register allocation.
>     It assigns hard register numbers to all the pseudo registers
> @@ -653,6 +654,8 @@ global_alloc (void)
>  	if (reg_renumber[allocno[allocno_order[i]].reg] < 0
>  	    && REG_LIVE_LENGTH (allocno[allocno_order[i]].reg) >= 0)
>  	  {
> +            if (!dbg_cnt (global_alloc_at_reg))
> +              break;
>  	    /* If we have more than one register class,
>  	       first try allocating in the class that is cheapest
>  	       for this pseudo-reg.  If that fails, try any reg.  */
> @@ -2049,7 +2052,7 @@ rest_of_handle_global_alloc (void)
>  
>    /* If optimizing, allocate remaining pseudo-regs.  Do the reload
>       pass fixing up any insns that are invalid.  */
> -  if (optimize)
> +  if (optimize && dbg_cnt (global_alloc_at_func))
>      failure = global_alloc ();
>    else
>      {
>