Re: Allow more WHOPR partitions than souce files

[Richard Guenther <rguenther@suse.de>]

On Fri, 3 Sep 2010, Jan Hubicka wrote:

> Hi,
> this patch makes collect2 to accept more partition files then number of original .o files
> on the command line.  This is needed for my partitioning patch that sometimes (for very
> large .o files) decide to break up single .o file into multiple.
> 
> Bootstrapped/regtested x86_64-linux, OK?

Ick.  Somebody ought to replace these arg arrays with a sane
datastructure when we're doing this kind of funny stuff.

Can you give that a try please?  You might need to enhance
VEC_splice to allow splicing in the middle of a vector.

Thanks,
Richard.

> Honza
> 
> 	* collect2.c (maybe_run_lto_and_relink): Allow number of partition files
> 	to exceed number of files.
> Index: collect2.c
> ===================================================================
> --- collect2.c	(revision 163809)
> +++ collect2.c	(working copy)
> @@ -942,12 +942,15 @@ maybe_run_lto_and_relink (char **lto_ld_
>      {
>        char **lto_c_argv;
>        const char **lto_c_ptr;
> -      const char **p, **q, **r;
> +      const char **p, **q, **r, **last_entry = NULL;
>        const char **lto_o_ptr;
>        struct lto_object *list;
>        char *lto_wrapper = getenv ("COLLECT_LTO_WRAPPER");
>        struct pex_obj *pex;
>        const char *prog = "lto-wrapper";
> +      int lto_ld_argv_size = 0;
> +      char **out_lto_ld_argv;
> +      size_t num_files;
>  
>        if (!lto_wrapper)
>  	fatal ("COLLECT_LTO_WRAPPER must be set.");
> @@ -973,7 +976,7 @@ maybe_run_lto_and_relink (char **lto_ld_
>        {
>  	int c;
>  	FILE *stream;
> -	size_t i, num_files;
> +	size_t i;
>  	char *start, *end;
>  
>  	stream = pex_read_output (pex, 0);
> @@ -1007,10 +1010,14 @@ maybe_run_lto_and_relink (char **lto_ld_
>        do_wait (prog, pex);
>        pex = NULL;
>  
> +      for (lto_ld_argv_size = 0; lto_ld_argv[lto_ld_argv_size]; lto_ld_argv_size++)
> +	;
> +      out_lto_ld_argv = XCNEWVEC(char *, num_files + lto_ld_argv_size + 1);
> +      memcpy (out_lto_ld_argv, lto_ld_argv, sizeof (char *) * lto_ld_argv_size);
>        /* After running the LTO back end, we will relink, substituting
>  	 the LTO output for the object files that we submitted to the
>  	 LTO. Here, we modify the linker command line for the relink.  */
> -      p = CONST_CAST2 (const char **, char **, lto_ld_argv);
> +      p = CONST_CAST2 (const char **, char **, out_lto_ld_argv);
>        lto_o_ptr = CONST_CAST2 (const char **, char **, lto_o_files);
>  
>        while (*p != NULL)
> @@ -1023,6 +1030,7 @@ maybe_run_lto_and_relink (char **lto_ld_
>                    if (*lto_o_ptr)
>                      {
>                        /* Replace first argument with LTO output file.  */
> +		      last_entry = p;
>                        *p++ = *lto_o_ptr++;
>                      }
>                    else
> @@ -1047,15 +1055,27 @@ maybe_run_lto_and_relink (char **lto_ld_
>            if (!list) ++p;
>          }
>  
> -      /* The code above assumes we will never have more lto output files than
> -	 input files.  Otherwise, we need to resize lto_ld_argv.  Check this
> -	 assumption.  */
> +      /* Insert remaining .o files just after last file appearing in the argument
> +	 sequence.  This way relative position of crtend and friends will be right.  */
>        if (*lto_o_ptr)
> -	fatal ("too many lto output files");
> +	{
> +	  size_t remaining_files = 0;
> +	  size_t tail_size = 0;
> +
> +	  for (p = lto_o_ptr; *p; p++)
> +	    remaining_files++;
> +	  for (p = last_entry + 1; *p; p++)
> +	    tail_size++;
> +	  memmove (last_entry + 1 + remaining_files,
> +		   last_entry + 1,
> +		   tail_size * sizeof (char *));
> +	  memcpy (last_entry + 1, lto_o_ptr, remaining_files * sizeof (char *));
> +	}
>  
>        /* Run the linker again, this time replacing the object files
>           optimized by the LTO with the temporary file generated by the LTO.  */
> -      fork_execute ("ld", lto_ld_argv);
> +      fork_execute ("ld", out_lto_ld_argv);
> +      free (lto_ld_argv);
>  
>        maybe_unlink_list (lto_o_files);
>      }
> 
> 

-- 
Richard Guenther <rguenther@suse.de>
Novell / SUSE Labs
SUSE LINUX Products GmbH - Nuernberg - AG Nuernberg - HRB 16746 - GF: Markus Rex