diff options
| author | Aldy Hernandez <aldyh@redhat.com> | 2021-10-27 16:24:53 +0200 |
|---|---|---|
| committer | Aldy Hernandez <aldyh@redhat.com> | 2021-10-27 20:14:15 +0200 |
| commit | 9f4edfc1fb80211f8663f978b7144e7e9d9df743 (patch) | |
| tree | 8bec933a210a7686220ac5530158ccb25000b26a /gcc | |
| parent | a1957c9755418f0f45a0bac296f61f486952960e (diff) | |
| download | gcc-9f4edfc1fb80211f8663f978b7144e7e9d9df743.zip gcc-9f4edfc1fb80211f8663f978b7144e7e9d9df743.tar.gz gcc-9f4edfc1fb80211f8663f978b7144e7e9d9df743.tar.bz2 | |
Kill second order relations in the path solver.
My upcoming work replacing the VRP threaders with a fully resolving
backward threader has tripped over various corner cases in the path
sensitive relation oracle. This patch kills second order relations when
we kill a relation.
Tested on x86-64 and ppc64le Linux.
Co-authored-by: Andrew MacLeod <amacleod@redhat.com>
gcc/ChangeLog:
* value-relation.cc (path_oracle::killing_def): Kill second
order relations.
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/value-relation.cc | 21 |
1 files changed, 20 insertions, 1 deletions
diff --git a/gcc/value-relation.cc b/gcc/value-relation.cc index 2acf375..0ad4f7a 100644 --- a/gcc/value-relation.cc +++ b/gcc/value-relation.cc @@ -1297,8 +1297,9 @@ path_oracle::killing_def (tree ssa) fprintf (dump_file, "\n"); } + unsigned v = SSA_NAME_VERSION (ssa); bitmap b = BITMAP_ALLOC (&m_bitmaps); - bitmap_set_bit (b, SSA_NAME_VERSION (ssa)); + bitmap_set_bit (b, v); equiv_chain *ptr = (equiv_chain *) obstack_alloc (&m_chain_obstack, sizeof (equiv_chain)); ptr->m_names = b; @@ -1306,6 +1307,24 @@ path_oracle::killing_def (tree ssa) ptr->m_next = m_equiv.m_next; m_equiv.m_next = ptr; bitmap_ior_into (m_equiv.m_names, b); + + // Walk the relation list an remove SSA from any relations. + if (!bitmap_bit_p (m_relations.m_names, v)) + return; + + bitmap_clear_bit (m_relations.m_names, v); + relation_chain **prev = &(m_relations.m_head); + relation_chain *next = NULL; + for (relation_chain *ptr = m_relations.m_head; ptr; ptr = next) + { + gcc_checking_assert (*prev == ptr); + next = ptr->m_next; + if (SSA_NAME_VERSION (ptr->op1 ()) == v + || SSA_NAME_VERSION (ptr->op2 ()) == v) + *prev = ptr->m_next; + else + prev = &(ptr->m_next); + } } // Register relation K between SSA1 and SSA2, resolving unknowns by |