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| author | Andrew MacLeod <amacleod@redhat.com> | 2023-04-12 13:10:55 -0400 |
|---|---|---|
| committer | Andrew MacLeod <amacleod@redhat.com> | 2023-04-13 14:12:04 -0400 |
| commit | 9c2a5db997446a9438a3e01f5229dec3f78b09e7 (patch) | |
| tree | 9cc090d2104f2033d75fbcc21db9e3314a337e89 /gcc | |
| parent | 52bb22bb5e1f951c73b5cd43b0b3a423f67e5e7a (diff) | |
| download | gcc-9c2a5db997446a9438a3e01f5229dec3f78b09e7.zip gcc-9c2a5db997446a9438a3e01f5229dec3f78b09e7.tar.gz gcc-9c2a5db997446a9438a3e01f5229dec3f78b09e7.tar.bz2 | |
Ensure PHI equivalencies do not dominate the argument edge.
When we create an equivalency between a PHI definition and an argument,
ensure the definition does not dominate the incoming argument edge.
PR tree-optimization/108139
PR tree-optimization/109462
* gimple-range-cache.cc (ranger_cache::fill_block_cache): Remove
equivalency check for PHI nodes.
* gimple-range-fold.cc (fold_using_range::range_of_phi): Ensure def
does not dominate single-arg equivalency edges.
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/gimple-range-cache.cc | 9 | ||||
| -rw-r--r-- | gcc/gimple-range-fold.cc | 23 |
2 files changed, 22 insertions, 10 deletions
diff --git a/gcc/gimple-range-cache.cc b/gcc/gimple-range-cache.cc index 3b52f1e..2314478 100644 --- a/gcc/gimple-range-cache.cc +++ b/gcc/gimple-range-cache.cc @@ -1220,7 +1220,7 @@ ranger_cache::fill_block_cache (tree name, basic_block bb, basic_block def_bb) // See if any equivalences can refine it. // PR 109462, like 108139 below, a one way equivalence introduced // by a PHI node can also be through the definition side. Disallow it. - if (m_oracle && !is_a<gphi *> (SSA_NAME_DEF_STMT (name))) + if (m_oracle) { tree equiv_name; relation_kind rel; @@ -1237,13 +1237,6 @@ ranger_cache::fill_block_cache (tree name, basic_block bb, basic_block def_bb) if (!m_gori.has_edge_range_p (equiv_name)) continue; - // PR 108139. It is hazardous to assume an equivalence with - // a PHI is the same value. The PHI may be an equivalence - // via UNDEFINED arguments which is really a one way equivalence. - // PHIDEF == name, but name may not be == PHIDEF. - if (is_a<gphi *> (SSA_NAME_DEF_STMT (equiv_name))) - continue; - // Check if the equiv definition dominates this block if (equiv_bb == bb || (equiv_bb && !dominated_by_p (CDI_DOMINATORS, bb, equiv_bb))) diff --git a/gcc/gimple-range-fold.cc b/gcc/gimple-range-fold.cc index e81f6b3..429734f 100644 --- a/gcc/gimple-range-fold.cc +++ b/gcc/gimple-range-fold.cc @@ -795,9 +795,28 @@ fold_using_range::range_of_phi (vrange &r, gphi *phi, fur_source &src) // If the PHI boils down to a single effective argument, look at it. if (single_arg) { - // Symbolic arguments are equivalences. + // Symbolic arguments can be equivalences. if (gimple_range_ssa_p (single_arg)) - src.register_relation (phi, VREL_EQ, phi_def, single_arg); + { + // Only allow the equivalence if the PHI definition does not + // dominate any incoming edge for SINGLE_ARG. + // See PR 108139 and 109462. + basic_block bb = gimple_bb (phi); + if (!dom_info_available_p (CDI_DOMINATORS)) + single_arg = NULL; + else + for (x = 0; x < gimple_phi_num_args (phi); x++) + if (gimple_phi_arg_def (phi, x) == single_arg + && dominated_by_p (CDI_DOMINATORS, + gimple_phi_arg_edge (phi, x)->src, + bb)) + { + single_arg = NULL; + break; + } + if (single_arg) + src.register_relation (phi, VREL_EQ, phi_def, single_arg); + } else if (src.get_operand (arg_range, single_arg) && arg_range.singleton_p ()) { |