diff options
Diffstat (limited to 'gcc/tree-ssa-sccvn.c')
| -rw-r--r-- | gcc/tree-ssa-sccvn.c | 87 |
1 files changed, 59 insertions, 28 deletions
diff --git a/gcc/tree-ssa-sccvn.c b/gcc/tree-ssa-sccvn.c index d4c2b46..a72a920 100644 --- a/gcc/tree-ssa-sccvn.c +++ b/gcc/tree-ssa-sccvn.c @@ -4203,19 +4203,6 @@ init_scc_vn (void) VN_TOP = create_tmp_var_raw (void_type_node, "vn_top"); - /* Create the VN_INFO structures, and initialize value numbers to - TOP. */ - for (i = 0; i < num_ssa_names; i++) - { - tree name = ssa_name (i); - if (name) - { - VN_INFO_GET (name)->valnum = VN_TOP; - VN_INFO (name)->expr = NULL_TREE; - VN_INFO (name)->value_id = 0; - } - } - renumber_gimple_stmt_uids (); /* Create the valid and optimistic value numbering tables. */ @@ -4223,6 +4210,65 @@ init_scc_vn (void) allocate_vn_table (valid_info); optimistic_info = XCNEW (struct vn_tables_s); allocate_vn_table (optimistic_info); + current_info = valid_info; + + /* Create the VN_INFO structures, and initialize value numbers to + TOP or VARYING for parameters. */ + for (i = 1; i < num_ssa_names; i++) + { + tree name = ssa_name (i); + if (!name) + continue; + + VN_INFO_GET (name)->valnum = VN_TOP; + VN_INFO (name)->expr = NULL_TREE; + VN_INFO (name)->value_id = 0; + + if (!SSA_NAME_IS_DEFAULT_DEF (name)) + continue; + + switch (TREE_CODE (SSA_NAME_VAR (name))) + { + case VAR_DECL: + /* Undefined vars keep TOP. */ + break; + + case PARM_DECL: + /* Parameters are VARYING but we can record a condition + if we know it is a non-NULL pointer. */ + VN_INFO (name)->visited = true; + VN_INFO (name)->valnum = name; + if (POINTER_TYPE_P (TREE_TYPE (name)) + && nonnull_arg_p (SSA_NAME_VAR (name))) + { + tree ops[2]; + ops[0] = name; + ops[1] = build_int_cst (TREE_TYPE (name), 0); + vn_nary_op_insert_pieces (2, NE_EXPR, boolean_type_node, ops, + boolean_true_node, 0); + if (dump_file && (dump_flags & TDF_DETAILS)) + { + fprintf (dump_file, "Recording "); + print_generic_expr (dump_file, name, TDF_SLIM); + fprintf (dump_file, " != 0\n"); + } + } + break; + + case RESULT_DECL: + /* If the result is passed by invisible reference the default + def is initialized, otherwise it's uninitialized. */ + if (DECL_BY_REFERENCE (SSA_NAME_VAR (name))) + { + VN_INFO (name)->visited = true; + VN_INFO (name)->valnum = name; + } + break; + + default: + gcc_unreachable (); + } + } } void @@ -4447,7 +4493,6 @@ sccvn_dom_walker::before_dom_children (basic_block bb) break; if (e2 && (e2->flags & EDGE_EXECUTABLE)) { - gimple stmt = last_stmt (e->src); if (stmt && gimple_code (stmt) == GIMPLE_COND) @@ -4573,24 +4618,10 @@ run_scc_vn (vn_lookup_kind default_vn_walk_kind_) { basic_block bb; size_t i; - tree param; default_vn_walk_kind = default_vn_walk_kind_; init_scc_vn (); - current_info = valid_info; - - for (param = DECL_ARGUMENTS (current_function_decl); - param; - param = DECL_CHAIN (param)) - { - tree def = ssa_default_def (cfun, param); - if (def) - { - VN_INFO (def)->visited = true; - VN_INFO (def)->valnum = def; - } - } /* Mark all edges as possibly executable. */ FOR_ALL_BB_FN (bb, cfun) |