diff options
| author | Martin Sebor <msebor@redhat.com> | 2018-07-26 16:45:43 +0000 |
|---|---|---|
| committer | Martin Sebor <msebor@gcc.gnu.org> | 2018-07-26 10:45:43 -0600 |
| commit | aca8570e11d28b8c33d26593df6d4725a6140aab (patch) | |
| tree | bea2270f62332f8d85e1bcd3adcb0c246cb32648 /gcc/tree.h | |
| parent | 4b8b1f5997e7f16713be5c05e7fd40c122fa9381 (diff) | |
PR tree-optimization/86043 - strlen after memcpy partially overwriting a string not optimized
PR tree-optimization/86043 - strlen after memcpy partially overwriting a string not optimized
PR tree-optimization/86042 - missing strlen optimization after second strcpy
gcc/ChangeLog:
PR tree-optimization/86043
PR tree-optimization/86042
* tree-ssa-strlen.c (handle_builtin_memcpy): Handle strict overlaps.
(get_string_cst_length): Rename...
(get_min_string_length): ...to this. Add argument.
(handle_char_store): Extend to handle multi-character stores by
MEM_REF.
* tree.c (initializer_zerop): Use new argument. Handle MEM_REF.
* tree.h (initializer_zerop): Add argument.
gcc/testsuite/ChangeLog:
PR tree-optimization/86043
PR tree-optimization/86042
* gcc/testsuite/gcc.dg/attr-nonstring-2.c: Xfail test cases due to
pr86688.
* gcc.dg/strlenopt-44.c: New test.
From-SVN: r263018
Diffstat (limited to 'gcc/tree.h')
| -rw-r--r-- | gcc/tree.h | 8 |
1 files changed, 6 insertions, 2 deletions
diff --git a/gcc/tree.h b/gcc/tree.h index 70ac78130c0..7bed03553b2 100644 --- a/gcc/tree.h +++ b/gcc/tree.h @@ -4429,9 +4429,13 @@ extern int list_length (const_tree); extern tree first_field (const_tree); /* Given an initializer INIT, return TRUE if INIT is zero or some - aggregate of zeros. Otherwise return FALSE. */ + aggregate of zeros. Otherwise return FALSE. If NONZERO is not + null, set *NONZERO if and only if INIT is known not to be all + zeros. The combination of return value of false and *NONZERO + false implies that INIT may but need not be all zeros. Other + combinations indicate definitive answers. */ -extern bool initializer_zerop (const_tree); +extern bool initializer_zerop (const_tree, bool * = NULL); extern wide_int vector_cst_int_elt (const_tree, unsigned int); extern tree vector_cst_elt (const_tree, unsigned int); |