[Bug tree-optimization/80769] Invalid delayed string length computation in tree-ssa-strlen.c

[rsandifo at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80769

--- Comment #3 from rsandifo at gcc dot gnu.org <rsandifo at gcc dot gnu.org> ---
Author: rsandifo
Date: Tue Aug  1 12:22:03 2017
New Revision: 250772

URL: https://gcc.gnu.org/viewcvs?rev=250772&root=gcc&view=rev
Log:
Backport fix for PR 80769

2017-08-01  Richard Sandiford  <richard.sandiford@linaro.org>

gcc/
        PR tree-optimization/80769
        * tree-ssa-strlen.c (strinfo): Document that "stmt" is also used
        for malloc and calloc.  Document the new invariant that all related
        strinfos have delayed lengths or none do.
        (get_next_strinfo): New function.
        (verify_related_strinfos): Move earlier in file.
        (set_endptr_and_length): New function, split out from...
        (get_string_length): ...here.  Also set the lengths of related
        strinfos.

gcc/testsuite/
        PR tree-optimization/80769
        * gcc.dg/strlenopt-31.c: New test.
        * gcc.dg/strlenopt-31g.c: Likewise.

Added:
    branches/gcc-7-branch/gcc/testsuite/gcc.dg/strlenopt-31.c
    branches/gcc-7-branch/gcc/testsuite/gcc.dg/strlenopt-31g.c
Modified:
    branches/gcc-7-branch/gcc/ChangeLog
    branches/gcc-7-branch/gcc/testsuite/ChangeLog
    branches/gcc-7-branch/gcc/tree-ssa-strlen.c