[PATCH] Convert strlen pass from evrp to ranger.

Aldy Hernandez aldyh@redhat.com
Sat Oct 9 18:47:29 GMT 2021


We seem to be passing a lot of context around in the strlen code.  I
certainly don't want to contribute to more.

Most of the handle_* functions are passing the gsi as well as either
ptr_qry or rvals.  That looks a bit messy.  May I suggest putting all
of that in the strlen pass object (well, the dom walker object, but we
can rename it to be less dom centric)?

Something like the attached (untested) patch could be the basis for
further cleanups.

Jakub, would this line of work interest you?

Aldy

On Fri, Oct 8, 2021 at 5:12 PM Aldy Hernandez <aldyh@redhat.com> wrote:
>
> The following patch converts the strlen pass from evrp to ranger,
> leaving DOM as the last remaining user.
>
> No additional cleanups have been done.  For example, the strlen pass
> still has uses of VR_ANTI_RANGE, and the sprintf still passes around
> pairs of integers instead of using a proper range.  Fixing this
> could further improve these passes.
>
> As a further enhancement, if the relevant maintainers deem useful,
> the domwalk could be removed from strlen.  That is, unless the pass
> needs it for something else.
>
> With ranger we are now able to remove the range calculation from
> before_dom_children entirely.  Just working with the ranger on-demand
> catches all the strlen and sprintf testcases with the exception of
> builtin-sprintf-warn-22.c which is due to a limitation of the sprintf
> code.  I have XFAILed the test and documented what the problem is.
>
> It looks like the same problem in the sprintf test triggers a false
> positive in gimple-ssa-warn-access.cc so I have added
> -Wno-format-overflow until it can be fixed.
>
> I can expand on the false positive if necessary, but the gist is that
> this:
>
>     _17 = strlen (_132);
>     _18 = strlen (_136);
>     _19 = _18 + _17;
>     if (_19 > 75)
>       goto <bb 59>; [0.00%]
>     else
>       goto <bb 61>; [100.00%]
>
> ...dominates the sprintf in BB61.  This means that ranger can figure
> out that the _17 and _18 are [0, 75].  On the other hand, evrp
> returned a range of [0, 9223372036854775805] which presumably the
> sprintf code was ignoring as a false positive here:
>
>               char sizstr[80];
>               ...
>               ...
>               char *s1 = print_generic_expr_to_str (sizrng[1]);
>               gcc_checking_assert (strlen (s0) + strlen (s1)
>                                    < sizeof sizstr - 4);
>               sprintf (sizstr, "[%s, %s]", s0, s1);
>
> The warning triggers with:
>
> gimple-ssa-warn-access.cc: In member function ‘void {anonymous}::pass_waccess::maybe_check_access_sizes(rdwr_map*, tree, tree, gimple*)’:
> gimple-ssa-warn-access.cc:2916:32: warning: ‘%s’ directive writing up to 75 bytes into a region of size between 2 and 77 [-Wformat-overflow=]
>  2916 |               sprintf (sizstr, "[%s, %s]", s0, s1);
>       |                                ^~~~~~~~~~
> gimple-ssa-warn-access.cc:2916:23: note: ‘sprintf’ output between 5 and 155 bytes into a destination of size 80
>  2916 |               sprintf (sizstr, "[%s, %s]", s0, s1);
>       |               ~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~
>
> On a positive note, these changes found two possible sprintf overflow
> bugs in the C++ and Fortran front-ends which I have fixed below.
>
> Bootstrap and regtested on x86-64 Linux.  I also ran it through our
> callgrind harness and there was no overall change in overall
> compilation time.
>
> OK?
>
> gcc/ChangeLog:
>
>         * Makefile.in: Disable -Wformat-overflow for
>         gimple-ssa-warn-access.o.
>         * tree-ssa-strlen.c (compare_nonzero_chars): Pass statement
>         context to ranger.
>         (get_addr_stridx): Same.
>         (get_stridx): Same.
>         (get_range_strlen_dynamic): Same.
>         (handle_builtin_strlen): Same.
>         (handle_builtin_strchr): Same.
>         (handle_builtin_strcpy): Same.
>         (maybe_diag_stxncpy_trunc): Same.
>         (handle_builtin_stxncpy_strncat):
>         (handle_builtin_memcpy): Same.
>         (handle_builtin_strcat): Same.
>         (handle_alloc_call): Same.
>         (handle_builtin_memset): Same.
>         (handle_builtin_string_cmp): Same.
>         (handle_pointer_plus): Same.
>         (count_nonzero_bytes_addr): Same.
>         (count_nonzero_bytes): Same.
>         (handle_store): Same.
>         (fold_strstr_to_strncmp): Same.
>         (handle_integral_assign): Same.
>         (check_and_optimize_stmt): Same.
>         (class strlen_dom_walker): Replace evrp with ranger.
>         (strlen_dom_walker::before_dom_children): Remove evrp.
>         (strlen_dom_walker::after_dom_children): Remove evrp.
>
> gcc/cp/ChangeLog:
>
>         * ptree.c (cxx_print_xnode): Add more space to pfx array.
>
> gcc/fortran/ChangeLog:
>
>         * misc.c (gfc_dummy_typename): Make sure ts->kind is
>         non-negative.
>
> gcc/testsuite/ChangeLog:
>
>         * gcc.dg/tree-ssa/builtin-sprintf-warn-22.c: XFAIL.
> ---
>  gcc/Makefile.in                               |   1 +
>  gcc/cp/ptree.c                                |   2 +-
>  gcc/fortran/misc.c                            |   2 +-
>  .../gcc.dg/tree-ssa/builtin-sprintf-warn-22.c |  13 +-
>  gcc/tree-ssa-strlen.c                         | 145 ++++++++++--------
>  5 files changed, 92 insertions(+), 71 deletions(-)
>
> diff --git a/gcc/Makefile.in b/gcc/Makefile.in
> index f36ffa4740b..dfd2a40e80a 100644
> --- a/gcc/Makefile.in
> +++ b/gcc/Makefile.in
> @@ -222,6 +222,7 @@ libgcov-merge-tool.o-warn = -Wno-error
>  gimple-match.o-warn = -Wno-unused
>  generic-match.o-warn = -Wno-unused
>  dfp.o-warn = -Wno-strict-aliasing
> +gimple-ssa-warn-access.o-warn = -Wno-format-overflow
>
>  # All warnings have to be shut off in stage1 if the compiler used then
>  # isn't gcc; configure determines that.  WARN_CFLAGS will be either
> diff --git a/gcc/cp/ptree.c b/gcc/cp/ptree.c
> index 1dcd764af01..ca7884db39b 100644
> --- a/gcc/cp/ptree.c
> +++ b/gcc/cp/ptree.c
> @@ -292,7 +292,7 @@ cxx_print_xnode (FILE *file, tree node, int indent)
>         for (unsigned ix = 0; ix != len; ix++)
>           {
>             binding_cluster *cluster = &BINDING_VECTOR_CLUSTER (node, ix);
> -           char pfx[24];
> +           char pfx[32];
>             for (unsigned jx = 0; jx != BINDING_VECTOR_SLOTS_PER_CLUSTER; jx++)
>               if (cluster->indices[jx].span)
>                 {
> diff --git a/gcc/fortran/misc.c b/gcc/fortran/misc.c
> index 3d449ae17fe..c1520307c90 100644
> --- a/gcc/fortran/misc.c
> +++ b/gcc/fortran/misc.c
> @@ -284,7 +284,7 @@ gfc_dummy_typename (gfc_typespec *ts)
>         {
>           if (ts->kind == gfc_default_character_kind)
>             sprintf(buffer, "CHARACTER(*)");
> -         else if (ts->kind < 10)
> +         else if (ts->kind >= 0 && ts->kind < 10)
>             sprintf(buffer, "CHARACTER(*,%d)", ts->kind);
>           else
>             sprintf(buffer, "CHARACTER(*,?)");
> diff --git a/gcc/testsuite/gcc.dg/tree-ssa/builtin-sprintf-warn-22.c b/gcc/testsuite/gcc.dg/tree-ssa/builtin-sprintf-warn-22.c
> index 685a4fd8c89..82eb5851c59 100644
> --- a/gcc/testsuite/gcc.dg/tree-ssa/builtin-sprintf-warn-22.c
> +++ b/gcc/testsuite/gcc.dg/tree-ssa/builtin-sprintf-warn-22.c
> @@ -18,7 +18,18 @@ void g (char *s1, char *s2)
>    if (n + d + 1 >= 1025)
>      return;
>
> -  sprintf (b, "%s.%s", s1, s2);     // { dg-bogus "\\\[-Wformat-overflow" }
> +  /* Ranger can find ranges here:
> +     [1] n_6: size_t [0, 1023]
> +     [2] d_8: size_t [0, 1023]
> +
> +     Whereas evrp can't really:
> +     [1] n_6: size_t [0, 9223372036854775805]
> +     [2] d_8: size_t [0, 9223372036854775805]
> +
> +     This is causing the sprintf warning pass to issue a false
> +     positive here.  */
> +
> +  sprintf (b, "%s.%s", s1, s2);     // { dg-bogus "\\\[-Wformat-overflow" "" { xfail *-*-* } }
>
>    f (b);
>  }
> diff --git a/gcc/tree-ssa-strlen.c b/gcc/tree-ssa-strlen.c
> index 7c568a42d49..df0c2d5ee7a 100644
> --- a/gcc/tree-ssa-strlen.c
> +++ b/gcc/tree-ssa-strlen.c
> @@ -59,7 +59,7 @@ along with GCC; see the file COPYING3.  If not see
>  #include "tree-ssa-loop.h"
>  #include "tree-scalar-evolution.h"
>  #include "vr-values.h"
> -#include "gimple-ssa-evrp-analyze.h"
> +#include "gimple-range.h"
>  #include "tree-ssa.h"
>
>  /* A vector indexed by SSA_NAME_VERSION.  0 means unknown, positive value
> @@ -256,7 +256,8 @@ compare_nonzero_chars (strinfo *si, unsigned HOST_WIDE_INT off)
>     Uses RVALS to determine length range.  */
>
>  static int
> -compare_nonzero_chars (strinfo *si, unsigned HOST_WIDE_INT off,
> +compare_nonzero_chars (strinfo *si, gimple *stmt,
> +                      unsigned HOST_WIDE_INT off,
>                        range_query *rvals)
>  {
>    if (!si->nonzero_chars)
> @@ -269,7 +270,7 @@ compare_nonzero_chars (strinfo *si, unsigned HOST_WIDE_INT off,
>      return -1;
>
>    value_range vr;
> -  if (!rvals->range_of_expr (vr, si->nonzero_chars, si->stmt))
> +  if (!rvals->range_of_expr (vr, si->nonzero_chars, stmt))
>      return -1;
>    value_range_kind rng = vr.kind ();
>    if (rng != VR_RANGE)
> @@ -324,7 +325,8 @@ get_next_strinfo (strinfo *si)
>     information.  */
>
>  static int
> -get_addr_stridx (tree exp, tree ptr, unsigned HOST_WIDE_INT *offset_out,
> +get_addr_stridx (tree exp, gimple *stmt,
> +                tree ptr, unsigned HOST_WIDE_INT *offset_out,
>                  range_query *rvals = NULL)
>  {
>    HOST_WIDE_INT off;
> @@ -363,7 +365,7 @@ get_addr_stridx (tree exp, tree ptr, unsigned HOST_WIDE_INT *offset_out,
>        unsigned HOST_WIDE_INT rel_off
>         = (unsigned HOST_WIDE_INT) off - last->offset;
>        strinfo *si = get_strinfo (last->idx);
> -      if (si && compare_nonzero_chars (si, rel_off, rvals) >= 0)
> +      if (si && compare_nonzero_chars (si, stmt, rel_off, rvals) >= 0)
>         {
>           if (offset_out)
>             {
> @@ -385,7 +387,8 @@ get_addr_stridx (tree exp, tree ptr, unsigned HOST_WIDE_INT *offset_out,
>     When nonnull, uses RVALS to determine range information.  */
>
>  static int
> -get_stridx (tree exp, wide_int offrng[2] = NULL, range_query *rvals = NULL)
> +get_stridx (tree exp, gimple *stmt,
> +           wide_int offrng[2] = NULL, range_query *rvals = NULL)
>  {
>    if (offrng)
>      offrng[0] = offrng[1] = wi::zero (TYPE_PRECISION (ptrdiff_type_node));
> @@ -522,7 +525,7 @@ get_stridx (tree exp, wide_int offrng[2] = NULL, range_query *rvals = NULL)
>
>    if (TREE_CODE (exp) == ADDR_EXPR)
>      {
> -      int idx = get_addr_stridx (TREE_OPERAND (exp, 0), exp, NULL);
> +      int idx = get_addr_stridx (TREE_OPERAND (exp, 0), stmt, exp, NULL);
>        if (idx != 0)
>         return idx;
>      }
> @@ -1016,7 +1019,7 @@ get_range_strlen_dynamic (tree src, gimple *stmt,
>                           c_strlen_data *pdata, bitmap *visited,
>                           range_query *rvals, unsigned *pssa_def_max)
>  {
> -  int idx = get_stridx (src);
> +  int idx = get_stridx (src, stmt);
>    if (!idx)
>      {
>        if (TREE_CODE (src) == SSA_NAME)
> @@ -2124,7 +2127,7 @@ handle_builtin_strlen (gimple_stmt_iterator *gsi)
>    tree src = gimple_call_arg (stmt, 0);
>    tree bound = (DECL_FUNCTION_CODE (callee) == BUILT_IN_STRNLEN
>                 ? gimple_call_arg (stmt, 1) : NULL_TREE);
> -  int idx = get_stridx (src);
> +  int idx = get_stridx (src, stmt);
>    if (idx || (bound && integer_zerop (bound)))
>      {
>        strinfo *si = NULL;
> @@ -2304,7 +2307,7 @@ handle_builtin_strchr (gimple_stmt_iterator *gsi)
>    if (!check_nul_terminated_array (NULL_TREE, src))
>      return;
>
> -  int idx = get_stridx (src);
> +  int idx = get_stridx (src, stmt);
>    if (idx)
>      {
>        strinfo *si = NULL;
> @@ -2411,12 +2414,12 @@ handle_builtin_strcpy (enum built_in_function bcode, gimple_stmt_iterator *gsi,
>    src = gimple_call_arg (stmt, 1);
>    dst = gimple_call_arg (stmt, 0);
>    lhs = gimple_call_lhs (stmt);
> -  idx = get_stridx (src);
> +  idx = get_stridx (src, stmt);
>    si = NULL;
>    if (idx > 0)
>      si = get_strinfo (idx);
>
> -  didx = get_stridx (dst);
> +  didx = get_stridx (dst, stmt);
>    olddsi = NULL;
>    oldlen = NULL_TREE;
>    if (didx > 0)
> @@ -2818,7 +2821,7 @@ maybe_diag_stxncpy_trunc (gimple_stmt_iterator gsi, tree src, tree cnt,
>       when ssa_ver_to_stridx is empty.  That implies the caller isn't
>       running under the control of this pass and ssa_ver_to_stridx hasn't
>       been created yet.  */
> -  int sidx = ssa_ver_to_stridx.length () ? get_stridx (src) : 0;
> +  int sidx = ssa_ver_to_stridx.length () ? get_stridx (src, stmt) : 0;
>    if (sidx < 0 && wi::gtu_p (cntrange[0], ~sidx))
>      return false;
>
> @@ -3092,7 +3095,7 @@ handle_builtin_stxncpy_strncat (bool append_p, gimple_stmt_iterator *gsi)
>       a lower bound).  */
>    tree dstlenp1 = NULL_TREE, srclenp1 = NULL_TREE;;
>
> -  int didx = get_stridx (dst);
> +  int didx = get_stridx (dst, stmt);
>    if (strinfo *sidst = didx > 0 ? get_strinfo (didx) : NULL)
>      {
>        /* Compute the size of the destination string including the nul
> @@ -3118,7 +3121,7 @@ handle_builtin_stxncpy_strncat (bool append_p, gimple_stmt_iterator *gsi)
>        dst = sidst->ptr;
>      }
>
> -  int sidx = get_stridx (src);
> +  int sidx = get_stridx (src, stmt);
>    strinfo *sisrc = sidx > 0 ? get_strinfo (sidx) : NULL;
>    if (sisrc)
>      {
> @@ -3228,7 +3231,7 @@ handle_builtin_memcpy (enum built_in_function bcode, gimple_stmt_iterator *gsi,
>    tree src = gimple_call_arg (stmt, 1);
>    tree dst = gimple_call_arg (stmt, 0);
>
> -  int didx = get_stridx (dst);
> +  int didx = get_stridx (dst, stmt);
>    strinfo *olddsi = NULL;
>    if (didx > 0)
>      olddsi = get_strinfo (didx);
> @@ -3242,7 +3245,7 @@ handle_builtin_memcpy (enum built_in_function bcode, gimple_stmt_iterator *gsi,
>        adjust_last_stmt (olddsi, stmt, false, ptr_qry);
>      }
>
> -  int idx = get_stridx (src);
> +  int idx = get_stridx (src, stmt);
>    if (idx == 0)
>      return;
>
> @@ -3418,7 +3421,7 @@ handle_builtin_strcat (enum built_in_function bcode, gimple_stmt_iterator *gsi,
>
>    tree lhs = gimple_call_lhs (stmt);
>
> -  didx = get_stridx (dst);
> +  didx = get_stridx (dst, stmt);
>    if (didx < 0)
>      return;
>
> @@ -3428,7 +3431,7 @@ handle_builtin_strcat (enum built_in_function bcode, gimple_stmt_iterator *gsi,
>
>    srclen = NULL_TREE;
>    si = NULL;
> -  idx = get_stridx (src);
> +  idx = get_stridx (src, stmt);
>    if (idx < 0)
>      srclen = build_int_cst (size_type_node, ~idx);
>    else if (idx > 0)
> @@ -3650,7 +3653,7 @@ handle_alloc_call (enum built_in_function bcode, gimple_stmt_iterator *gsi)
>    if (lhs == NULL_TREE)
>      return;
>
> -  gcc_assert (get_stridx (lhs) == 0);
> +  gcc_assert (get_stridx (lhs, stmt) == 0);
>    int idx = new_stridx (lhs);
>    tree length = NULL_TREE;
>    if (bcode == BUILT_IN_CALLOC)
> @@ -3687,7 +3690,7 @@ handle_builtin_memset (gimple_stmt_iterator *gsi, bool *zero_write,
>    tree ptr = gimple_call_arg (memset_stmt, 0);
>    /* Set to the non-constant offset added to PTR.  */
>    wide_int offrng[2];
> -  int idx1 = get_stridx (ptr, offrng, ptr_qry.rvals);
> +  int idx1 = get_stridx (ptr, memset_stmt, offrng, ptr_qry.rvals);
>    if (idx1 <= 0)
>      return false;
>    strinfo *si1 = get_strinfo (idx1);
> @@ -4178,8 +4181,8 @@ handle_builtin_string_cmp (gimple_stmt_iterator *gsi, range_query *rvals)
>
>    tree arg1 = gimple_call_arg (stmt, 0);
>    tree arg2 = gimple_call_arg (stmt, 1);
> -  int idx1 = get_stridx (arg1);
> -  int idx2 = get_stridx (arg2);
> +  int idx1 = get_stridx (arg1, stmt);
> +  int idx2 = get_stridx (arg2, stmt);
>
>    /* For strncmp set to the value of the third argument if known.  */
>    HOST_WIDE_INT bound = -1;
> @@ -4318,7 +4321,7 @@ handle_pointer_plus (gimple_stmt_iterator *gsi)
>  {
>    gimple *stmt = gsi_stmt (*gsi);
>    tree lhs = gimple_assign_lhs (stmt), off;
> -  int idx = get_stridx (gimple_assign_rhs1 (stmt));
> +  int idx = get_stridx (gimple_assign_rhs1 (stmt), stmt);
>    strinfo *si, *zsi;
>
>    if (idx == 0)
> @@ -4396,7 +4399,8 @@ nonzero_bytes_for_type (tree type, unsigned lenrange[3],
>  }
>
>  static bool
> -count_nonzero_bytes_addr (tree, unsigned HOST_WIDE_INT, unsigned HOST_WIDE_INT,
> +count_nonzero_bytes_addr (tree, gimple *stmt,
> +                         unsigned HOST_WIDE_INT, unsigned HOST_WIDE_INT,
>                           unsigned [3], bool *, bool *, bool *,
>                           range_query *, ssa_name_limit_t &);
>
> @@ -4416,7 +4420,8 @@ count_nonzero_bytes_addr (tree, unsigned HOST_WIDE_INT, unsigned HOST_WIDE_INT,
>     Returns true on success and false otherwise.  */
>
>  static bool
> -count_nonzero_bytes (tree exp, unsigned HOST_WIDE_INT offset,
> +count_nonzero_bytes (tree exp, gimple *stmt,
> +                    unsigned HOST_WIDE_INT offset,
>                      unsigned HOST_WIDE_INT nbytes,
>                      unsigned lenrange[3], bool *nulterm,
>                      bool *allnul, bool *allnonnul, range_query *rvals,
> @@ -4435,7 +4440,8 @@ count_nonzero_bytes (tree exp, unsigned HOST_WIDE_INT offset,
>              exact value is not known) recurse once to set the range
>              for an arbitrary constant.  */
>           exp = build_int_cst (type, 1);
> -         return count_nonzero_bytes (exp, offset, 1, lenrange,
> +         return count_nonzero_bytes (exp, stmt,
> +                                     offset, 1, lenrange,
>                                       nulterm, allnul, allnonnul, rvals, snlim);
>         }
>
> @@ -4462,7 +4468,8 @@ count_nonzero_bytes (tree exp, unsigned HOST_WIDE_INT offset,
>           for (unsigned i = 0; i != n; i++)
>             {
>               tree def = gimple_phi_arg_def (stmt, i);
> -             if (!count_nonzero_bytes (def, offset, nbytes, lenrange, nulterm,
> +             if (!count_nonzero_bytes (def, stmt,
> +                                       offset, nbytes, lenrange, nulterm,
>                                         allnul, allnonnul, rvals, snlim))
>                 return false;
>             }
> @@ -4519,7 +4526,8 @@ count_nonzero_bytes (tree exp, unsigned HOST_WIDE_INT offset,
>         return false;
>
>        /* Handle MEM_REF = SSA_NAME types of assignments.  */
> -      return count_nonzero_bytes_addr (arg, offset, nbytes, lenrange, nulterm,
> +      return count_nonzero_bytes_addr (arg, stmt,
> +                                      offset, nbytes, lenrange, nulterm,
>                                        allnul, allnonnul, rvals, snlim);
>      }
>
> @@ -4631,13 +4639,14 @@ count_nonzero_bytes (tree exp, unsigned HOST_WIDE_INT offset,
>     bytes that are pointed to by EXP, which should be a pointer.  */
>
>  static bool
> -count_nonzero_bytes_addr (tree exp, unsigned HOST_WIDE_INT offset,
> +count_nonzero_bytes_addr (tree exp, gimple *stmt,
> +                         unsigned HOST_WIDE_INT offset,
>                           unsigned HOST_WIDE_INT nbytes,
>                           unsigned lenrange[3], bool *nulterm,
>                           bool *allnul, bool *allnonnul,
>                           range_query *rvals, ssa_name_limit_t &snlim)
>  {
> -  int idx = get_stridx (exp);
> +  int idx = get_stridx (exp, stmt);
>    if (idx > 0)
>      {
>        strinfo *si = get_strinfo (idx);
> @@ -4653,7 +4662,7 @@ count_nonzero_bytes_addr (tree exp, unsigned HOST_WIDE_INT offset,
>                && TREE_CODE (si->nonzero_chars) == SSA_NAME)
>         {
>           value_range vr;
> -         rvals->range_of_expr (vr, si->nonzero_chars, si->stmt);
> +         rvals->range_of_expr (vr, si->nonzero_chars, stmt);
>           if (vr.kind () != VR_RANGE)
>             return false;
>
> @@ -4699,7 +4708,8 @@ count_nonzero_bytes_addr (tree exp, unsigned HOST_WIDE_INT offset,
>      }
>
>    if (TREE_CODE (exp) == ADDR_EXPR)
> -    return count_nonzero_bytes (TREE_OPERAND (exp, 0), offset, nbytes,
> +    return count_nonzero_bytes (TREE_OPERAND (exp, 0), stmt,
> +                               offset, nbytes,
>                                 lenrange, nulterm, allnul, allnonnul, rvals,
>                                 snlim);
>
> @@ -4719,7 +4729,8 @@ count_nonzero_bytes_addr (tree exp, unsigned HOST_WIDE_INT offset,
>           for (unsigned i = 0; i != n; i++)
>             {
>               tree def = gimple_phi_arg_def (stmt, i);
> -             if (!count_nonzero_bytes_addr (def, offset, nbytes, lenrange,
> +             if (!count_nonzero_bytes_addr (def, stmt,
> +                                            offset, nbytes, lenrange,
>                                              nulterm, allnul, allnonnul, rvals,
>                                              snlim))
>                 return false;
> @@ -4747,7 +4758,8 @@ count_nonzero_bytes_addr (tree exp, unsigned HOST_WIDE_INT offset,
>     (the results of strlen).  */
>
>  static bool
> -count_nonzero_bytes (tree expr_or_type, unsigned lenrange[3], bool *nulterm,
> +count_nonzero_bytes (tree expr_or_type, gimple *stmt,
> +                    unsigned lenrange[3], bool *nulterm,
>                      bool *allnul, bool *allnonnul, range_query *rvals)
>  {
>    if (TYPE_P (expr_or_type))
> @@ -4765,7 +4777,8 @@ count_nonzero_bytes (tree expr_or_type, unsigned lenrange[3], bool *nulterm,
>
>    ssa_name_limit_t snlim;
>    tree expr = expr_or_type;
> -  return count_nonzero_bytes (expr, 0, 0, lenrange, nulterm, allnul, allnonnul,
> +  return count_nonzero_bytes (expr, stmt,
> +                             0, 0, lenrange, nulterm, allnul, allnonnul,
>                               rvals, snlim);
>  }
>
> @@ -4818,18 +4831,19 @@ handle_store (gimple_stmt_iterator *gsi, bool *zero_write,
>              least OFFSET nonzero characters.  This is trivially true if
>              OFFSET is zero.  */
>           offset = tree_to_uhwi (mem_offset);
> -         idx = get_stridx (TREE_OPERAND (lhs, 0));
> +         idx = get_stridx (TREE_OPERAND (lhs, 0), stmt);
>           if (idx > 0)
>             si = get_strinfo (idx);
>           if (offset == 0)
>             ssaname = TREE_OPERAND (lhs, 0);
> -         else if (si == NULL || compare_nonzero_chars (si, offset, rvals) < 0)
> +         else if (si == NULL
> +                  || compare_nonzero_chars (si, stmt, offset, rvals) < 0)
>             {
>               *zero_write = rhs ? initializer_zerop (rhs) : false;
>
>               bool dummy;
>               unsigned lenrange[] = { UINT_MAX, 0, 0 };
> -             if (count_nonzero_bytes (rhs ? rhs : storetype, lenrange,
> +             if (count_nonzero_bytes (rhs ? rhs : storetype, stmt, lenrange,
>                                        &dummy, &dummy, &dummy, rvals))
>                 maybe_warn_overflow (stmt, true, lenrange[2], ptr_qry);
>
> @@ -4839,7 +4853,7 @@ handle_store (gimple_stmt_iterator *gsi, bool *zero_write,
>      }
>    else
>      {
> -      idx = get_addr_stridx (lhs, NULL_TREE, &offset, rvals);
> +      idx = get_addr_stridx (lhs, stmt, NULL_TREE, &offset, rvals);
>        if (idx > 0)
>         si = get_strinfo (idx);
>      }
> @@ -4862,7 +4876,8 @@ handle_store (gimple_stmt_iterator *gsi, bool *zero_write,
>    bool full_string_p;
>
>    const bool ranges_valid
> -    = count_nonzero_bytes (rhs ? rhs : storetype, lenrange, &full_string_p,
> +    = count_nonzero_bytes (rhs ? rhs : storetype, stmt,
> +                          lenrange, &full_string_p,
>                            &storing_all_zeros_p, &storing_all_nonzero_p,
>                            rvals);
>
> @@ -4895,15 +4910,18 @@ handle_store (gimple_stmt_iterator *gsi, bool *zero_write,
>         {
>           /* The offset of the last stored byte.  */
>           unsigned HOST_WIDE_INT endoff = offset + lenrange[2] - 1;
> -         store_before_nul[0] = compare_nonzero_chars (si, offset, rvals);
> +         store_before_nul[0]
> +           = compare_nonzero_chars (si, stmt, offset, rvals);
>           if (endoff == offset)
>             store_before_nul[1] = store_before_nul[0];
>           else
> -           store_before_nul[1] = compare_nonzero_chars (si, endoff, rvals);
> +           store_before_nul[1]
> +             = compare_nonzero_chars (si, stmt, endoff, rvals);
>         }
>        else
>         {
> -         store_before_nul[0] = compare_nonzero_chars (si, offset, rvals);
> +         store_before_nul[0]
> +           = compare_nonzero_chars (si, stmt, offset, rvals);
>           store_before_nul[1] = store_before_nul[0];
>           gcc_assert (offset == 0 || store_before_nul[0] >= 0);
>         }
> @@ -5128,7 +5146,7 @@ fold_strstr_to_strncmp (tree rhs1, tree rhs2, gimple *stmt)
>         {
>           tree arg1 = gimple_call_arg (call_stmt, 1);
>           tree arg1_len = NULL_TREE;
> -         int idx = get_stridx (arg1);
> +         int idx = get_stridx (arg1, call_stmt);
>
>           if (idx)
>             {
> @@ -5342,7 +5360,7 @@ handle_integral_assign (gimple_stmt_iterator *gsi, bool *cleanup_eh,
>        tree rhs1 = gimple_assign_rhs1 (stmt);
>        if (code == MEM_REF)
>         {
> -         idx = get_stridx (TREE_OPERAND (rhs1, 0));
> +         idx = get_stridx (TREE_OPERAND (rhs1, 0), stmt);
>           if (idx > 0)
>             {
>               strinfo *si = get_strinfo (idx);
> @@ -5359,7 +5377,7 @@ handle_integral_assign (gimple_stmt_iterator *gsi, bool *cleanup_eh,
>             }
>         }
>        if (idx <= 0)
> -       idx = get_addr_stridx (rhs1, NULL_TREE, &coff);
> +       idx = get_addr_stridx (rhs1, stmt, NULL_TREE, &coff);
>        if (idx > 0)
>         {
>           strinfo *si = get_strinfo (idx);
> @@ -5421,7 +5439,8 @@ handle_integral_assign (gimple_stmt_iterator *gsi, bool *cleanup_eh,
>           unsigned lenrange[] = { UINT_MAX, 0, 0 };
>           tree rhs = gimple_assign_rhs1 (stmt);
>           const bool ranges_valid
> -           = count_nonzero_bytes (rhs, lenrange, &full_string_p,
> +           = count_nonzero_bytes (rhs, stmt,
> +                                  lenrange, &full_string_p,
>                                    &storing_all_zeros_p, &storing_all_nonzero_p,
>                                    rvals);
>           if (ranges_valid)
> @@ -5520,7 +5539,7 @@ check_and_optimize_stmt (gimple_stmt_iterator *gsi, bool *cleanup_eh,
>               || (gimple_assign_cast_p (stmt)
>                   && POINTER_TYPE_P (TREE_TYPE (gimple_assign_rhs1 (stmt)))))
>             {
> -             int idx = get_stridx (gimple_assign_rhs1 (stmt));
> +             int idx = get_stridx (gimple_assign_rhs1 (stmt), stmt);
>               ssa_ver_to_stridx[SSA_NAME_VERSION (lhs)] = idx;
>             }
>           else if (gimple_assign_rhs_code (stmt) == POINTER_PLUS_EXPR)
> @@ -5602,20 +5621,20 @@ class strlen_dom_walker : public dom_walker
>  public:
>    strlen_dom_walker (cdi_direction direction)
>      : dom_walker (direction),
> -    evrp (false),
> -    ptr_qry (&evrp, &var_cache),
> -    var_cache (),
> -    m_cleanup_cfg (false)
> -  { }
> +      ptr_qry (&m_ranger, &var_cache),
> +      var_cache (),
> +      m_cleanup_cfg (false)
> +  {
> +  }
>
>    ~strlen_dom_walker ();
>
>    virtual edge before_dom_children (basic_block);
>    virtual void after_dom_children (basic_block);
>
> -  /* EVRP analyzer used for printf argument range processing, and
> +  /* Ranger used for printf argument range processing, and
>       to track strlen results across integer variable assignments.  */
> -  evrp_range_analyzer evrp;
> +  gimple_ranger m_ranger;
>
>    /* A pointer_query object and its cache to store information about
>       pointers and their targets in.  */
> @@ -5640,8 +5659,6 @@ strlen_dom_walker::~strlen_dom_walker ()
>  edge
>  strlen_dom_walker::before_dom_children (basic_block bb)
>  {
> -  evrp.enter (bb);
> -
>    basic_block dombb = get_immediate_dominator (CDI_DOMINATORS, bb);
>
>    if (dombb == NULL)
> @@ -5698,12 +5715,12 @@ strlen_dom_walker::before_dom_children (basic_block bb)
>        tree result = gimple_phi_result (phi);
>        if (!virtual_operand_p (result) && POINTER_TYPE_P (TREE_TYPE (result)))
>         {
> -         int idx = get_stridx (gimple_phi_arg_def (phi, 0));
> +         int idx = get_stridx (gimple_phi_arg_def (phi, 0), phi);
>           if (idx != 0)
>             {
>               unsigned int i, n = gimple_phi_num_args (phi);
>               for (i = 1; i < n; i++)
> -               if (idx != get_stridx (gimple_phi_arg_def (phi, i)))
> +               if (idx != get_stridx (gimple_phi_arg_def (phi, i), phi))
>                   break;
>               if (i == n)
>                 ssa_ver_to_stridx[SSA_NAME_VERSION (result)] = idx;
> @@ -5716,12 +5733,6 @@ strlen_dom_walker::before_dom_children (basic_block bb)
>    /* Attempt to optimize individual statements.  */
>    for (gimple_stmt_iterator gsi = gsi_start_bb (bb); !gsi_end_p (gsi); )
>      {
> -      gimple *stmt = gsi_stmt (gsi);
> -
> -      /* First record ranges generated by this statement so they
> -        can be used by printf argument processing.  */
> -      evrp.record_ranges_from_stmt (stmt, false);
> -
>        /* Reset search depth preformance counter.  */
>        ptr_qry.depth = 0;
>
> @@ -5744,8 +5755,6 @@ strlen_dom_walker::before_dom_children (basic_block bb)
>  void
>  strlen_dom_walker::after_dom_children (basic_block bb)
>  {
> -  evrp.leave (bb);
> -
>    if (bb->aux)
>      {
>        stridx_to_strinfo = ((vec<strinfo *, va_heap, vl_embed> *) bb->aux);
> --
> 2.31.1
>
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