diff options
| author | Martin Sebor <msebor@redhat.com> | 2019-10-18 22:26:39 +0000 |
|---|---|---|
| committer | Martin Sebor <msebor@gcc.gnu.org> | 2019-10-18 16:26:39 -0600 |
| commit | 9c233ad0cb1b31ed305c3534e3d9279e5af43477 (patch) | |
| tree | e9f7c5dce019404c15ccc589c01af1b2b26ae813 /gcc/tree-ssa-strlen.c | |
| parent | f8b9b1edef77be79b3f98021f9d1f24a1e986ffd (diff) | |
| download | gcc-9c233ad0cb1b31ed305c3534e3d9279e5af43477.zip gcc-9c233ad0cb1b31ed305c3534e3d9279e5af43477.tar.gz gcc-9c233ad0cb1b31ed305c3534e3d9279e5af43477.tar.bz2 | |
PR tree-optimization/92157 - incorrect strcmp() == 0 result for unknown strings
gcc/testsuite/ChangeLog:
PR tree-optimization/92157
* gcc.dg/strlenopt-69.c: Disable test failing due to PR 92155.
* gcc.dg/strlenopt-87.c: New test.
gcc/ChangeLog:
PR tree-optimization/92157
* tree-ssa-strlen.c (handle_builtin_string_cmp): Be prepared for
compute_string_length to return a negative result.
From-SVN: r277194
Diffstat (limited to 'gcc/tree-ssa-strlen.c')
| -rw-r--r-- | gcc/tree-ssa-strlen.c | 12 |
1 files changed, 10 insertions, 2 deletions
diff --git a/gcc/tree-ssa-strlen.c b/gcc/tree-ssa-strlen.c index d5833f69..4381458 100644 --- a/gcc/tree-ssa-strlen.c +++ b/gcc/tree-ssa-strlen.c @@ -3842,7 +3842,7 @@ handle_builtin_string_cmp (gimple_stmt_iterator *gsi) HOST_WIDE_INT arysiz1 = -1, arysiz2 = -1; if (idx1) - cstlen1 = compute_string_length (idx1) + 1; + cstlen1 = compute_string_length (idx1); else arysiz1 = determine_min_objsize (arg1); @@ -3853,13 +3853,21 @@ handle_builtin_string_cmp (gimple_stmt_iterator *gsi) /* Repeat for the second argument. */ if (idx2) - cstlen2 = compute_string_length (idx2) + 1; + cstlen2 = compute_string_length (idx2); else arysiz2 = determine_min_objsize (arg2); if (cstlen2 < 0 && arysiz2 < 0) return false; + if (cstlen1 < 0 && cstlen2 < 0) + return false; + + if (cstlen1 >= 0) + ++cstlen1; + if (cstlen2 >= 0) + ++cstlen2; + /* The exact number of characters to compare. */ HOST_WIDE_INT cmpsiz = bound < 0 ? cstlen1 < 0 ? cstlen2 : cstlen1 : bound; /* The size of the array in which the unknown string is stored. */ |