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| author | David Malcolm <dmalcolm@redhat.com> | 2021-07-21 17:24:08 -0400 |
|---|---|---|
| committer | David Malcolm <dmalcolm@redhat.com> | 2021-07-21 17:24:08 -0400 |
| commit | e0a7a6752dad7848eb4b29b826a551c0992256ec (patch) | |
| tree | 81a2f099b94604fbc59132682e0e095a89d8b96f /gcc/analyzer/region-model.h | |
| parent | 6bbad96cd44774bc199b256dbf4260b25b87c7db (diff) | |
| download | gcc-e0a7a6752dad7848eb4b29b826a551c0992256ec.tar.gz | |
analyzer: fix issues with phi handling
The analyzer's state purging code was overzealously purging state
for ssa names that might be used within phi nodes, leading to
false positives from -Wanalyzer-use-of-uninitialized-value.
This patch updates phi handling in the analyzer to fix these issues.
gcc/analyzer/ChangeLog:
* region-model.cc (region_model::handle_phi): Add "old_state"
param and use it.
(region_model::update_for_phis): Update so that all of the phi
stmts are effectively handled simultaneously, rather than in
order.
* region-model.h (region_model::handle_phi): Add "old_state"
param.
* state-purge.cc (self_referential_phi_p): Replace with...
(name_used_by_phis_p): ...this new function.
(state_purge_per_ssa_name::process_point): Update to use the
above, so that all phi stmts at a basic block are effectively
considered simultaneously, and only consider the phi arguments for
the pertinent in-edge.
* supergraph.cc (cfg_superedge::get_phi_arg_idx): New.
(cfg_superedge::get_phi_arg): Use the above.
* supergraph.h (cfg_superedge::get_phi_arg_idx): New decl.
gcc/testsuite/ChangeLog:
* gcc.dg/analyzer/explode-2.c: Remove xfail.
* gcc.dg/analyzer/explode-2a.c: Remove expected leak warning on
while stmt.
* gcc.dg/analyzer/phi-2.c: New test.
Signed-off-by: David Malcolm <dmalcolm@redhat.com>
Diffstat (limited to 'gcc/analyzer/region-model.h')
| -rw-r--r-- | gcc/analyzer/region-model.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/gcc/analyzer/region-model.h b/gcc/analyzer/region-model.h index 734ec601237..cc39929db26 100644 --- a/gcc/analyzer/region-model.h +++ b/gcc/analyzer/region-model.h @@ -582,6 +582,7 @@ class region_model region_model_context *ctxt); void handle_phi (const gphi *phi, tree lhs, tree rhs, + const region_model &old_state, region_model_context *ctxt); bool maybe_update_for_edge (const superedge &edge, |