On Wed, Jan 3, 2018 at 1:58 PM, Michael W. Bombardieri <m...@ii.net> wrote:
> Hello,
>
> In yacc the function print_grammar() writes the file y.output if
> the -v option is used. fprintf() can be used directly for writing
> "spacing" space characters of indentation so a loop can be removed.
>
> - Michael
>
>
> Index: reader.c
> ===================================================================
> RCS file: /cvs/src/usr.bin/yacc/reader.c,v
> retrieving revision 1.34
> diff -u -p -u -r1.34 reader.c
> --- reader.c 25 May 2017 20:11:03 -0000 1.34
> +++ reader.c 3 Jan 2018 12:40:54 -0000
> @@ -1806,7 +1806,7 @@ pack_grammar(void)
> void
> print_grammar(void)
> {
> - int i, j, k;
> + int i, k;
> int spacing = 0;
> FILE *f = verbose_file;
>
> @@ -1822,9 +1822,8 @@ print_grammar(void)
> spacing = strlen(symbol_name[rlhs[i]]) + 1;
> } else {
> fprintf(f, "%4d ", i - 2);
> - j = spacing;
> - while (--j >= 0)
> - putc(' ', f);
> + if (spacing > 0)
> + fprintf(f, "%*s", spacing, "");
> putc('|', f);
> }
This takes longer to understand, requires a check for a special case,
and likely ends up being slower.
