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| author | Jakub Jelinek <jakub@redhat.com> | 2023-01-04 12:16:22 +0100 |
|---|---|---|
| committer | Jakub Jelinek <jakub@redhat.com> | 2023-01-04 12:16:22 +0100 |
| commit | ebc449119442501c927ede0e83697eaece72223e (patch) | |
| tree | 229d0671534b2446b2ae1b945a01e99d580c95fd /gcc/tree-vrp.cc | |
| parent | 345dffd0d4ebff7e705dfff1a8a72017a167120a (diff) | |
| download | gcc-ebc449119442501c927ede0e83697eaece72223e.zip gcc-ebc449119442501c927ede0e83697eaece72223e.tar.gz gcc-ebc449119442501c927ede0e83697eaece72223e.tar.bz2 | |
vrp: Handle pointers in maybe_set_nonzero_bits [PR108253]
maybe_set_nonzero_bits calls set_nonzero_bits which asserts that
var doesn't have pointer type. While we could punt for those
cases, I think we can handle at least some easy cases.
Earlier in maybe_set_nonzero_bits we've checked this is on
(var & cst) == 0
edge and the other edge is __builtin_unreachable, so if cst
is say 3 as in the testcase, we want to turn it into 4 byte alignment
of the pointer.
2023-01-04 Jakub Jelinek <jakub@redhat.com>
PR tree-optimization/108253
* tree-vrp.cc (maybe_set_nonzero_bits): Handle var with pointer
types.
* g++.dg/opt/pr108253.C: New test.
Diffstat (limited to 'gcc/tree-vrp.cc')
| -rw-r--r-- | gcc/tree-vrp.cc | 18 |
1 files changed, 16 insertions, 2 deletions
diff --git a/gcc/tree-vrp.cc b/gcc/tree-vrp.cc index 0dfea5a..3c43176 100644 --- a/gcc/tree-vrp.cc +++ b/gcc/tree-vrp.cc @@ -789,8 +789,22 @@ maybe_set_nonzero_bits (edge e, tree var) return; } cst = gimple_assign_rhs2 (stmt); - set_nonzero_bits (var, wi::bit_and_not (get_nonzero_bits (var), - wi::to_wide (cst))); + if (POINTER_TYPE_P (TREE_TYPE (var))) + { + struct ptr_info_def *pi = SSA_NAME_PTR_INFO (var); + if (pi && pi->misalign) + return; + wide_int w = wi::bit_not (wi::to_wide (cst)); + unsigned int bits = wi::ctz (w); + if (bits == 0 || bits >= HOST_BITS_PER_INT) + return; + unsigned int align = 1U << bits; + if (pi == NULL || pi->align < align) + set_ptr_info_alignment (get_ptr_info (var), align, 0); + } + else + set_nonzero_bits (var, wi::bit_and_not (get_nonzero_bits (var), + wi::to_wide (cst))); } /* Searches the case label vector VEC for the index *IDX of the CASE_LABEL |