diff options
| author | Richard Biener <rguenther@suse.de> | 2024-01-31 11:28:50 +0100 |
|---|---|---|
| committer | Richard Biener <rguenther@suse.de> | 2024-05-06 13:52:20 +0200 |
| commit | 47cd06042237bf2d4f05b8355362bc038f6fa445 (patch) | |
| tree | c99e737865a2fdb0fe4ecc5418f8e8ad031a1fd4 | |
| parent | 429935510202c4efee933bf907fd9dff816193f2 (diff) | |
tree-optimization/113630 - invalid code hoisting
The following avoids code hoisting (but also PRE insertion) of
expressions that got value-numbered to another one that are not
a valid replacement (but still compute the same value). This time
because the access path ends in a structure with different size,
meaning we consider a related access as not trapping because of the
size of the base of the access.
PR tree-optimization/113630
* tree-ssa-pre.cc (compute_avail): Avoid registering a
reference with a representation with not matching base
access size.
* gcc.dg/torture/pr113630.c: New testcase.
(cherry picked from commit 724b64304ff5c8ac08a913509afd6fde38d7b767)
| -rw-r--r-- | gcc/testsuite/gcc.dg/torture/pr113630.c | 4 | ||||
| -rw-r--r-- | gcc/tree-ssa-pre.cc | 14 |
2 files changed, 18 insertions, 0 deletions
diff --git a/gcc/testsuite/gcc.dg/torture/pr113630.c b/gcc/testsuite/gcc.dg/torture/pr113630.c new file mode 100644 index 00000000000..72ebdefae27 --- /dev/null +++ b/gcc/testsuite/gcc.dg/torture/pr113630.c @@ -0,0 +1,4 @@ +/* { dg-do run { target { { *-*-linux* *-*-gnu* *-*-uclinux* } && mmap } } } */ +/* { dg-additional-options "-fno-strict-aliasing" } */ + +#include "pr110799.c" diff --git a/gcc/tree-ssa-pre.cc b/gcc/tree-ssa-pre.cc index dfcc9ec4711..9e9a2f9d26a 100644 --- a/gcc/tree-ssa-pre.cc +++ b/gcc/tree-ssa-pre.cc @@ -4224,6 +4224,20 @@ compute_avail (function *fun) = wide_int_to_tree (ptr_type_node, wi::to_wide (ref1->op2)); } + /* We also need to make sure that the access path + ends in an access of the same size as otherwise + we might assume an access may not trap while in + fact it might. That's independent of whether + TBAA is in effect. */ + if (TYPE_SIZE (ref1->type) != TYPE_SIZE (ref2->type) + && (! TYPE_SIZE (ref1->type) + || ! TYPE_SIZE (ref2->type) + || ! operand_equal_p (TYPE_SIZE (ref1->type), + TYPE_SIZE (ref2->type)))) + { + operands.release (); + continue; + } operands.release (); result = get_or_alloc_expr_for_reference |