diff options
Diffstat (limited to 'gcc/tree-ssa-sccvn.c')
| -rw-r--r-- | gcc/tree-ssa-sccvn.c | 21 |
1 files changed, 19 insertions, 2 deletions
diff --git a/gcc/tree-ssa-sccvn.c b/gcc/tree-ssa-sccvn.c index 4f5e852..e7502de 100644 --- a/gcc/tree-ssa-sccvn.c +++ b/gcc/tree-ssa-sccvn.c @@ -2820,6 +2820,15 @@ vn_nary_op_insert_into (vn_nary_op_t vno, vn_nary_op_table_type *table, vno->hashcode = vn_nary_op_compute_hash (vno); slot = table->find_slot_with_hash (vno, vno->hashcode, INSERT); + /* While we do not want to insert things twice it's awkward to + avoid it in the case where visit_nary_op pattern-matches stuff + and ends up simplifying the replacement to itself. We then + get two inserts, one from visit_nary_op and one from + vn_nary_build_or_lookup. + So allow inserts with the same value number. */ + if (*slot && (*slot)->result == vno->result) + return *slot; + gcc_assert (!*slot); *slot = vno; @@ -3544,7 +3553,11 @@ visit_nary_op (tree lhs, gassign *stmt) result = vn_nary_build_or_lookup (NOP_EXPR, type, ops); if (result) - return set_ssa_val_to (lhs, result); + { + bool changed = set_ssa_val_to (lhs, result); + vn_nary_op_insert_stmt (stmt, result); + return changed; + } } else { @@ -3555,7 +3568,11 @@ visit_nary_op (tree lhs, gassign *stmt) TREE_TYPE (lhs), ops); if (result) - return set_ssa_val_to (lhs, result); + { + bool changed = set_ssa_val_to (lhs, result); + vn_nary_op_insert_stmt (stmt, result); + return changed; + } } } } |