Re: [PATCH] style: decouple different uses of item_number

[Akim Demaille]

> Le 25 mai 2020 à 14:41, Vincent Imbimbo <address@hidden> a écrit :
> 
> Hey Akim,
> 
> I'm confused about these item_indices you've changed to item_number, since
> state->items is an array of item_indices.

Hi Vincent,

My turn to be confused: what you show is going from item_number to index.
Maybe you're showing the diff in your repo instead of quoting my patch?
Here it is.

> diff --git a/src/closure.c b/src/closure.c
> index 94439b13..ee0c9d4a 100644
> --- a/src/closure.c
> +++ b/src/closure.c
> @@ -60,10 +60,10 @@ closure_print (char const *title, item_index const 
> *array, size_t size)
>    for (size_t i = 0; i < size; ++i)
>      {
>        fprintf (stderr, "  %2d: .", array[i]);
> -      item_index *rp;
> -      for (rp = &ritem[array[i]]; *rp >= 0; ++rp)
> +      item_number *rp;
> +      for (rp = &ritem[array[i]]; 0 <= *rp; ++rp)

rp is clearly iterating on ritem, which is a an array of item_numbers.

>          fprintf (stderr, " %s", symbols[*rp]->tag);
> -      fprintf (stderr, "  (rule %d)\n", -*rp - 1);
> +      fprintf (stderr, "  (rule %d)\n", item_number_as_rule_number (*rp));
>      }
>    fputs ("\n\n", stderr);
>  }
> diff --git a/src/gram.h b/src/gram.h
> index a4b58f0a..77fc7699 100644
> --- a/src/gram.h
> +++ b/src/gram.h
> @@ -111,14 +111,15 @@ extern int nsyms;
>  extern int ntokens;
>  extern int nvars;
>  
> -/* elements of ritem */
> +/* Elements of ritem. */
>  typedef int item_number;
> -/* indices into ritem */
> -typedef int item_index;
>  # define ITEM_NUMBER_MAX INT_MAX
>  extern item_number *ritem;
>  extern int nritems;
>  
> +/* Indices into ritem. */
> +typedef unsigned int item_index;
> +
>  /* There is weird relationship between OT1H item_number and OTOH
>     symbol_number and rule_number: we store the latter in
>     item_number.  symbol_number values are stored as-is, while
> diff --git a/src/ielr.c b/src/ielr.c
> index f86cd461..47ac714a 100644
> --- a/src/ielr.c
> +++ b/src/ielr.c
> @@ -1030,7 +1030,7 @@ ielr_split_states (bitsetv follow_kernel_items, bitsetv 
> always_follows,
>          if (!node->state->consistent)
>            {
>              size_t i = 0;
> -            item_number *itemset = node->state->items;
> +            item_index *itemset = node->state->items;

struct state is:


struct state
{
  state_number number;
...
  /* Its items.  Must be last, since ITEMS can be arbitrarily large.  Sorted
     ascendingly on item index in RITEM, which is sorted on rule number.  */
  size_t nitems;
  item_index items[1];
};

So my change is consistent with yours.  And indeed it seems to be correct,
since, for instance:



>              for (size_t r = 0; r < node->state->reductions->num; ++r)
>                {
>                  rule *this_rule = node->state->reductions->rules[r];
> diff --git a/src/print-xml.c b/src/print-xml.c
> index a44af211..168d6bd5 100644
> --- a/src/print-xml.c
> +++ b/src/print-xml.c
> @@ -57,7 +57,7 @@ static struct escape_buf escape_bufs[num_escape_bufs];
>  static void
>  print_core (FILE *out, int level, state *s)
>  {
> -  item_number *sitems = s->items;
> +  item_index *sitems = s->items;
>    size_t snritems = s->nitems;
>  
>    /* Output all the items of a state, not only its kernel.  */


this continues with:

  /* Output all the items of a state, not only its kernel.  */
  closure (sitems, snritems);
  sitems = itemset;
  snritems = nitemset;

  if (!snritems)
    {
      xml_puts (out, level, "<itemset/>");
      return;
    }

  xml_puts (out, level, "<itemset>");

  for (size_t i = 0; i < snritems; i++)
    {
      bool printed = false;
      item_number *sp1 = ritem + sitems[i];
      rule const *r = item_rule (sp1);
      item_number *sp = r->rhs;

so indeed, sitems[i] is used as an index inside ritem, so it's an index.



> diff --git a/src/print.c b/src/print.c
> index 720740ee..1da0f9dd 100644
> --- a/src/print.c
> +++ b/src/print.c
> @@ -61,7 +61,7 @@ max_length (size_t *width, const char *str)
>  static void
>  print_core (FILE *out, state *s)
>  {
> -  item_number *sitems = s->items;
> +  item_index *sitems = s->items;
>    size_t snritems = s->nitems;
>    /* Output all the items of a state, not only its kernel.  */
>    if (report_flag & report_itemsets)



So I don't understand what is the problem you noticed.  You'll have to be more
specific, I don't see it :(

Cheers!