On Thu, 5 Mar 2020, Jakub Jelinek wrote:
> Hi!
>
> The following testcase fails to assemble, as CONST_STRING in the DEBUG_INSNs
> is printed as is, so if it contains \n and/or \r, we are in trouble:
> .loc 1 14 3
> # DEBUG haystack => [si]
> # DEBUG needle => "
> "
> In the gimple dumps we print those (STRING_CSTs) as
> # DEBUG haystack => D#1
> # DEBUG needle => "\n"
> so this patch uses what we use in tree printing for the CONST_STRINGs too.
> I think it isn't really useful to print gigabytes for very long strings,
> so the patch also shrinks the string with ... at the end indicating
> continuation, but if you think that is undesirable, I can leave it out
> (though, at least theoretically, while STRING_CSTs can't be longer than
> 2GB because tree_string has int length, CONST_STRING is just a pointer
> without length and thus on 64-bit hosts could be longer, so if not capping
> at 1K, I think we need to cap at 2GB-1 or 4GB-1 (pretty_print_string
> takes unsigned nbytes). Or of course we can change it to size_t nbytes.
It looks like tree-pretty-print.c doesn't bother to truncate it
so why bother for RTL?
So OK with not pruning the string for now.
Thanks,
Richard.
> Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?
>
> 2020-03-05 Jakub Jelinek <ja...@redhat.com>
>
> PR middle-end/93399
> * tree-pretty-print.h (pretty_print_string): Declare.
> * tree-pretty-print.c (pretty_print_string): Remove forward
> declaration, no longer static.
> * print-rtl.c (print_value) <case CONST_STRING>: Use
> pretty_print_string and for shrink way too long strings.
>
> * gcc.dg/pr93399.c: New test.
>
> --- gcc/tree-pretty-print.h.jj 2020-01-12 11:54:38.499381937 +0100
> +++ gcc/tree-pretty-print.h 2020-03-04 14:50:22.737021195 +0100
> @@ -47,6 +47,7 @@ extern void print_declaration (pretty_pr
> extern int op_code_prio (enum tree_code);
> extern int op_prio (const_tree);
> extern const char *op_symbol_code (enum tree_code);
> +extern void pretty_print_string (pretty_printer *, const char *, unsigned);
> extern void print_call_name (pretty_printer *, tree, dump_flags_t);
> extern void percent_K_format (text_info *, location_t, tree);
> extern void pp_tree_identifier (pretty_printer *, tree);
> --- gcc/tree-pretty-print.c.jj 2020-01-30 17:55:50.411163667 +0100
> +++ gcc/tree-pretty-print.c 2020-03-04 14:49:53.673451945 +0100
> @@ -45,7 +45,6 @@ along with GCC; see the file COPYING3.
>
> /* Local functions, macros and variables. */
> static const char *op_symbol (const_tree);
> -static void pretty_print_string (pretty_printer *, const char*, unsigned);
> static void newline_and_indent (pretty_printer *, int);
> static void maybe_init_pretty_print (FILE *);
> static void print_struct_decl (pretty_printer *, const_tree, int,
> dump_flags_t);
> @@ -4216,7 +4215,7 @@ print_call_name (pretty_printer *pp, tre
> /* Print the first N characters in the array STR, replacing non-printable
> characters (including embedded nuls) with unambiguous escape sequences.
> */
>
> -static void
> +void
> pretty_print_string (pretty_printer *pp, const char *str, unsigned n)
> {
> if (str == NULL)
> --- gcc/print-rtl.c.jj 2020-01-12 11:54:36.915405835 +0100
> +++ gcc/print-rtl.c 2020-03-04 14:55:55.089094999 +0100
> @@ -1685,7 +1685,15 @@ print_value (pretty_printer *pp, const_r
> pp_string (pp, tmp);
> break;
> case CONST_STRING:
> - pp_printf (pp, "\"%s\"", XSTR (x, 0));
> + pp_string (pp, "\"");
> + if (size_t nbytes = strlen (XSTR (x, 0)))
> + {
> + unsigned int n = MIN (nbytes, 1024);
> + pretty_print_string (pp, XSTR (x, 0), n);
> + if (n != nbytes)
> + pp_string (pp, "...");
> + }
> + pp_string (pp, "\"");
> break;
> case SYMBOL_REF:
> pp_printf (pp, "`%s'", XSTR (x, 0));
> --- gcc/testsuite/gcc.dg/pr93399.c.jj 2020-03-04 15:20:01.281631147 +0100
> +++ gcc/testsuite/gcc.dg/pr93399.c 2020-03-04 15:19:18.426266715 +0100
> @@ -0,0 +1,17 @@
> +/* PR middle-end/93399 */
> +/* { dg-do assemble } */
> +/* { dg-options "-fverbose-asm -dA -g -O3" } */
> +
> +extern inline __attribute__ ((__always_inline__, __gnu_inline__)) char *
> +strstr (const char *haystack, const char *needle)
> +{
> + return __builtin_strstr (haystack, needle);
> +}
> +
> +int
> +main (int argc, const char **argv)
> +{
> + char *substr = strstr (argv[0], "\n");
> + char *another = strstr (argv[0], "\r\n");
> + return 0;
> +}
>
> Jakub
>
>
--
Richard Biener <rguent...@suse.de>
SUSE Software Solutions Germany GmbH, Maxfeldstrasse 5, 90409 Nuernberg,
Germany; GF: Felix Imendörffer; HRB 36809 (AG Nuernberg)
