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| author | Martin Sebor <msebor@redhat.com> | 2019-10-08 19:48:27 +0000 |
|---|---|---|
| committer | Martin Sebor <msebor@gcc.gnu.org> | 2019-10-08 13:48:27 -0600 |
| commit | 7c3ed632601bf485335a7fe00d1db34b23ebacd2 (patch) | |
| tree | fcb0679a35fe62400fe8291b8fae30c2ca980686 /gcc/tree-ssa-strlen.c | |
| parent | e86fc0d7a8df5799c195cd5ff0486e0bdbe6c661 (diff) | |
| download | gcc-7c3ed632601bf485335a7fe00d1db34b23ebacd2.zip gcc-7c3ed632601bf485335a7fe00d1db34b23ebacd2.tar.gz gcc-7c3ed632601bf485335a7fe00d1db34b23ebacd2.tar.bz2 | |
PR middle-end/92026 - gcc.dg/Wstringop-overflow-18.c FAIL
PR middle-end/92026 - gcc.dg/Wstringop-overflow-18.c FAIL
PR middle-end/92014 - bogus warning: writing 8 bytes into a region of size 1 in timezone/zic.c
gcc/ChangeLog:
* tree-ssa-strlen.c (count_nonzero_bytes): Avoid recursing for MEM_REF
again once nbytes has been set. Set the access size when not yet set.
gcc/testsuite/ChangeLog:
PR middle-end/92014
* gcc.dg/Wstringop-overflow-19.c: New test.
From-SVN: r276711
Diffstat (limited to 'gcc/tree-ssa-strlen.c')
| -rw-r--r-- | gcc/tree-ssa-strlen.c | 28 |
1 files changed, 17 insertions, 11 deletions
diff --git a/gcc/tree-ssa-strlen.c b/gcc/tree-ssa-strlen.c index d68df19..c2866e0 100644 --- a/gcc/tree-ssa-strlen.c +++ b/gcc/tree-ssa-strlen.c @@ -3741,13 +3741,16 @@ int ssa_name_limit_t::next_ssa_name (tree ssa_name) return 0; } -/* Determine the minimum and maximum number of leading non-zero bytes +/* Determines the minimum and maximum number of leading non-zero bytes in the representation of EXP and set LENRANGE[0] and LENRANGE[1] - to each. Set LENRANGE[2] to the total number of bytes in - the representation. Set *NULTREM if the representation contains - a zero byte, and set *ALLNUL if all the bytes are zero. Avoid - recursing deeper than the limits in SNLIM allow. Return true - on success and false otherwise. */ + to each. Sets LENRANGE[2] to the total number of bytes in + the representation. Sets *NULTREM if the representation contains + a zero byte, and sets *ALLNUL if all the bytes are zero. + OFFSET and NBYTES are the offset into the representation and + the size of the access to it determined from a MEM_REF or zero + for other expressions. + Avoid recursing deeper than the limits in SNLIM allow. + Returns true on success and false otherwise. */ static bool count_nonzero_bytes (tree exp, unsigned HOST_WIDE_INT offset, @@ -3769,15 +3772,13 @@ count_nonzero_bytes (tree exp, unsigned HOST_WIDE_INT offset, return false; len -= offset; - size -= offset; - - if (size < nbytes) - return false; if (len < lenrange[0]) lenrange[0] = len; if (lenrange[1] < len) lenrange[1] = len; + if (lenrange[2] < nbytes) + lenrange[2] = nbytes; if (!si->full_string_p) *nulterm = false; @@ -3843,6 +3844,9 @@ count_nonzero_bytes (tree exp, unsigned HOST_WIDE_INT offset, if (TREE_CODE (exp) == MEM_REF) { + if (nbytes) + return false; + tree arg = TREE_OPERAND (exp, 0); tree off = TREE_OPERAND (exp, 1); @@ -3910,8 +3914,10 @@ count_nonzero_bytes (tree exp, unsigned HOST_WIDE_INT offset, lenrange[0] = 0; prep = NULL; } - else + else if (!nbytes) nbytes = repsize; + else if (nbytes < repsize) + return false; } if (!nbytes) |