| /* AST Optimizer */ |
| #include "Python.h" |
| #include "Python-ast.h" |
| |
| |
| /* TODO: is_const and get_const_value are copied from Python/compile.c. |
| It should be deduped in the future. Maybe, we can include this file |
| from compile.c? |
| */ |
| static int |
| is_const(expr_ty e) |
| { |
| switch (e->kind) { |
| case Constant_kind: |
| case Num_kind: |
| case Str_kind: |
| case Bytes_kind: |
| case Ellipsis_kind: |
| case NameConstant_kind: |
| return 1; |
| default: |
| return 0; |
| } |
| } |
| |
| static PyObject * |
| get_const_value(expr_ty e) |
| { |
| switch (e->kind) { |
| case Constant_kind: |
| return e->v.Constant.value; |
| case Num_kind: |
| return e->v.Num.n; |
| case Str_kind: |
| return e->v.Str.s; |
| case Bytes_kind: |
| return e->v.Bytes.s; |
| case Ellipsis_kind: |
| return Py_Ellipsis; |
| case NameConstant_kind: |
| return e->v.NameConstant.value; |
| default: |
| Py_UNREACHABLE(); |
| } |
| } |
| |
| static int |
| make_const(expr_ty node, PyObject *val, PyArena *arena) |
| { |
| if (val == NULL) { |
| if (PyErr_ExceptionMatches(PyExc_KeyboardInterrupt)) { |
| return 0; |
| } |
| PyErr_Clear(); |
| return 1; |
| } |
| if (PyArena_AddPyObject(arena, val) < 0) { |
| Py_DECREF(val); |
| return 0; |
| } |
| node->kind = Constant_kind; |
| node->v.Constant.value = val; |
| return 1; |
| } |
| |
| #define COPY_NODE(TO, FROM) (memcpy((TO), (FROM), sizeof(struct _expr))) |
| |
| static PyObject* |
| unary_not(PyObject *v) |
| { |
| int r = PyObject_IsTrue(v); |
| if (r < 0) |
| return NULL; |
| return PyBool_FromLong(!r); |
| } |
| |
| static int |
| fold_unaryop(expr_ty node, PyArena *arena) |
| { |
| expr_ty arg = node->v.UnaryOp.operand; |
| |
| if (!is_const(arg)) { |
| /* Fold not into comparison */ |
| if (node->v.UnaryOp.op == Not && arg->kind == Compare_kind && |
| asdl_seq_LEN(arg->v.Compare.ops) == 1) { |
| /* Eq and NotEq are often implemented in terms of one another, so |
| folding not (self == other) into self != other breaks implementation |
| of !=. Detecting such cases doesn't seem worthwhile. |
| Python uses </> for 'is subset'/'is superset' operations on sets. |
| They don't satisfy not folding laws. */ |
| int op = asdl_seq_GET(arg->v.Compare.ops, 0); |
| switch (op) { |
| case Is: |
| op = IsNot; |
| break; |
| case IsNot: |
| op = Is; |
| break; |
| case In: |
| op = NotIn; |
| break; |
| case NotIn: |
| op = In; |
| break; |
| default: |
| op = 0; |
| } |
| if (op) { |
| asdl_seq_SET(arg->v.Compare.ops, 0, op); |
| COPY_NODE(node, arg); |
| return 1; |
| } |
| } |
| return 1; |
| } |
| |
| typedef PyObject *(*unary_op)(PyObject*); |
| static const unary_op ops[] = { |
| [Invert] = PyNumber_Invert, |
| [Not] = unary_not, |
| [UAdd] = PyNumber_Positive, |
| [USub] = PyNumber_Negative, |
| }; |
| PyObject *newval = ops[node->v.UnaryOp.op](get_const_value(arg)); |
| return make_const(node, newval, arena); |
| } |
| |
| static int |
| fold_binop(expr_ty node, PyArena *arena) |
| { |
| expr_ty lhs, rhs; |
| lhs = node->v.BinOp.left; |
| rhs = node->v.BinOp.right; |
| if (!is_const(lhs) || !is_const(rhs)) { |
| return 1; |
| } |
| |
| PyObject *lv = get_const_value(lhs); |
| PyObject *rv = get_const_value(rhs); |
| PyObject *newval; |
| |
| switch (node->v.BinOp.op) { |
| case Add: |
| newval = PyNumber_Add(lv, rv); |
| break; |
| case Sub: |
| newval = PyNumber_Subtract(lv, rv); |
| break; |
| case Mult: |
| newval = PyNumber_Multiply(lv, rv); |
| break; |
| case Div: |
| newval = PyNumber_TrueDivide(lv, rv); |
| break; |
| case FloorDiv: |
| newval = PyNumber_FloorDivide(lv, rv); |
| break; |
| case Mod: |
| newval = PyNumber_Remainder(lv, rv); |
| break; |
| case Pow: |
| newval = PyNumber_Power(lv, rv, Py_None); |
| break; |
| case LShift: |
| newval = PyNumber_Lshift(lv, rv); |
| break; |
| case RShift: |
| newval = PyNumber_Rshift(lv, rv); |
| break; |
| case BitOr: |
| newval = PyNumber_Or(lv, rv); |
| break; |
| case BitXor: |
| newval = PyNumber_Xor(lv, rv); |
| break; |
| case BitAnd: |
| newval = PyNumber_And(lv, rv); |
| break; |
| default: // Unknown operator |
| return 1; |
| } |
| |
| if (newval == NULL) { |
| if (PyErr_ExceptionMatches(PyExc_KeyboardInterrupt)) { |
| return 0; |
| } |
| PyErr_Clear(); |
| return 1; |
| } |
| |
| /* Avoid creating large constants. */ |
| Py_ssize_t size = PyObject_Size(newval); |
| if (size == -1) { |
| if (PyErr_ExceptionMatches(PyExc_KeyboardInterrupt)) { |
| Py_DECREF(newval); |
| return 0; |
| } |
| PyErr_Clear(); |
| } |
| else if (size > 20) { |
| Py_DECREF(newval); |
| return 1; |
| } |
| return make_const(node, newval, arena); |
| } |
| |
| static PyObject* |
| make_const_tuple(asdl_seq *elts, int make_set) |
| { |
| for (int i = 0; i < asdl_seq_LEN(elts); i++) { |
| expr_ty e = (expr_ty)asdl_seq_GET(elts, i); |
| if (!is_const(e)) { |
| return NULL; |
| } |
| } |
| |
| PyObject *newval = PyTuple_New(asdl_seq_LEN(elts)); |
| if (newval == NULL) { |
| return NULL; |
| } |
| |
| for (int i = 0; i < asdl_seq_LEN(elts); i++) { |
| expr_ty e = (expr_ty)asdl_seq_GET(elts, i); |
| PyObject *v = get_const_value(e); |
| Py_INCREF(v); |
| PyTuple_SET_ITEM(newval, i, v); |
| } |
| |
| /* Need to create frozen_set instead. */ |
| if (make_set) { |
| Py_SETREF(newval, PyFrozenSet_New(newval)); |
| } |
| return newval; |
| } |
| |
| static int |
| fold_tuple(expr_ty node, PyArena *arena) |
| { |
| PyObject *newval; |
| |
| if (node->v.Tuple.ctx != Load) |
| return 1; |
| |
| newval = make_const_tuple(node->v.Tuple.elts, 0); |
| return make_const(node, newval, arena); |
| } |
| |
| static int |
| fold_subscr(expr_ty node, PyArena *arena) |
| { |
| PyObject *newval; |
| expr_ty arg, idx; |
| slice_ty slice; |
| |
| arg = node->v.Subscript.value; |
| slice = node->v.Subscript.slice; |
| if (node->v.Subscript.ctx != Load || |
| !is_const(arg) || |
| /* TODO: handle other types of slices */ |
| slice->kind != Index_kind || |
| !is_const(slice->v.Index.value)) |
| { |
| return 1; |
| } |
| |
| idx = slice->v.Index.value; |
| newval = PyObject_GetItem(get_const_value(arg), get_const_value(idx)); |
| return make_const(node, newval, arena); |
| } |
| |
| static int |
| fold_compare(expr_ty node, PyArena *arena) |
| { |
| asdl_int_seq *ops; |
| asdl_seq *args; |
| PyObject *newval; |
| int i; |
| |
| ops = node->v.Compare.ops; |
| args = node->v.Compare.comparators; |
| /* TODO: optimize cases with literal arguments. */ |
| for (i = 0; i < asdl_seq_LEN(ops); i++) { |
| int op; |
| expr_ty arg; |
| asdl_seq *elts; |
| |
| op = asdl_seq_GET(ops, i); |
| arg = (expr_ty)asdl_seq_GET(args, i); |
| /* Change literal list or set in 'in' or 'not in' into |
| tuple or frozenset respectively. */ |
| /* TODO: do the same when list or set is used as iterable |
| in for loop and comprehensions? */ |
| if (op != In && op != NotIn) |
| continue; |
| if (arg->kind == List_kind) |
| elts = arg->v.List.elts; |
| else if (arg->kind == Set_kind) |
| elts = arg->v.Set.elts; |
| else continue; |
| |
| newval = make_const_tuple(elts, arg->kind == Set_kind); |
| make_const(arg, newval, arena); |
| } |
| return 1; |
| } |
| |
| static int astfold_mod(mod_ty node_, PyArena* ctx_); |
| static int astfold_stmt(stmt_ty node_, PyArena* ctx_); |
| static int astfold_expr(expr_ty node_, PyArena* ctx_); |
| static int astfold_arguments(arguments_ty node_, PyArena* ctx_); |
| static int astfold_comprehension(comprehension_ty node_, PyArena* ctx_); |
| static int astfold_keyword(keyword_ty node_, PyArena* ctx_); |
| static int astfold_slice(slice_ty node_, PyArena* ctx_); |
| static int astfold_arg(arg_ty node_, PyArena* ctx_); |
| static int astfold_withitem(withitem_ty node_, PyArena* ctx_); |
| static int astfold_excepthandler(excepthandler_ty node_, PyArena* ctx_); |
| #define CALL(FUNC, TYPE, ARG) \ |
| if (!FUNC((ARG), ctx_)) \ |
| return 0; |
| |
| #define CALL_OPT(FUNC, TYPE, ARG) \ |
| if ((ARG) != NULL && !FUNC((ARG), ctx_)) \ |
| return 0; |
| |
| #define CALL_SEQ(FUNC, TYPE, ARG) { \ |
| int i; \ |
| asdl_seq *seq = (ARG); /* avoid variable capture */ \ |
| for (i = 0; i < asdl_seq_LEN(seq); i++) { \ |
| TYPE elt = (TYPE)asdl_seq_GET(seq, i); \ |
| if (elt != NULL && !FUNC(elt, ctx_)) \ |
| return 0; \ |
| } \ |
| } |
| |
| #define CALL_INT_SEQ(FUNC, TYPE, ARG) { \ |
| int i; \ |
| asdl_int_seq *seq = (ARG); /* avoid variable capture */ \ |
| for (i = 0; i < asdl_seq_LEN(seq); i++) { \ |
| TYPE elt = (TYPE)asdl_seq_GET(seq, i); \ |
| if (!FUNC(elt, ctx_)) \ |
| return 0; \ |
| } \ |
| } |
| |
| static int |
| astfold_mod(mod_ty node_, PyArena* ctx_) |
| { |
| switch (node_->kind) { |
| case Module_kind: |
| CALL_SEQ(astfold_stmt, stmt_ty, node_->v.Module.body); |
| break; |
| case Interactive_kind: |
| CALL_SEQ(astfold_stmt, stmt_ty, node_->v.Interactive.body); |
| break; |
| case Expression_kind: |
| CALL(astfold_expr, expr_ty, node_->v.Expression.body); |
| break; |
| case Suite_kind: |
| CALL_SEQ(astfold_stmt, stmt_ty, node_->v.Suite.body); |
| break; |
| default: |
| break; |
| } |
| return 1; |
| } |
| |
| static int |
| astfold_expr(expr_ty node_, PyArena* ctx_) |
| { |
| switch (node_->kind) { |
| case BoolOp_kind: |
| CALL_SEQ(astfold_expr, expr_ty, node_->v.BoolOp.values); |
| break; |
| case BinOp_kind: |
| CALL(astfold_expr, expr_ty, node_->v.BinOp.left); |
| CALL(astfold_expr, expr_ty, node_->v.BinOp.right); |
| CALL(fold_binop, expr_ty, node_); |
| break; |
| case UnaryOp_kind: |
| CALL(astfold_expr, expr_ty, node_->v.UnaryOp.operand); |
| CALL(fold_unaryop, expr_ty, node_); |
| break; |
| case Lambda_kind: |
| CALL(astfold_arguments, arguments_ty, node_->v.Lambda.args); |
| CALL(astfold_expr, expr_ty, node_->v.Lambda.body); |
| break; |
| case IfExp_kind: |
| CALL(astfold_expr, expr_ty, node_->v.IfExp.test); |
| CALL(astfold_expr, expr_ty, node_->v.IfExp.body); |
| CALL(astfold_expr, expr_ty, node_->v.IfExp.orelse); |
| break; |
| case Dict_kind: |
| CALL_SEQ(astfold_expr, expr_ty, node_->v.Dict.keys); |
| CALL_SEQ(astfold_expr, expr_ty, node_->v.Dict.values); |
| break; |
| case Set_kind: |
| CALL_SEQ(astfold_expr, expr_ty, node_->v.Set.elts); |
| break; |
| case ListComp_kind: |
| CALL(astfold_expr, expr_ty, node_->v.ListComp.elt); |
| CALL_SEQ(astfold_comprehension, comprehension_ty, node_->v.ListComp.generators); |
| break; |
| case SetComp_kind: |
| CALL(astfold_expr, expr_ty, node_->v.SetComp.elt); |
| CALL_SEQ(astfold_comprehension, comprehension_ty, node_->v.SetComp.generators); |
| break; |
| case DictComp_kind: |
| CALL(astfold_expr, expr_ty, node_->v.DictComp.key); |
| CALL(astfold_expr, expr_ty, node_->v.DictComp.value); |
| CALL_SEQ(astfold_comprehension, comprehension_ty, node_->v.DictComp.generators); |
| break; |
| case GeneratorExp_kind: |
| CALL(astfold_expr, expr_ty, node_->v.GeneratorExp.elt); |
| CALL_SEQ(astfold_comprehension, comprehension_ty, node_->v.GeneratorExp.generators); |
| break; |
| case Await_kind: |
| CALL(astfold_expr, expr_ty, node_->v.Await.value); |
| break; |
| case Yield_kind: |
| CALL_OPT(astfold_expr, expr_ty, node_->v.Yield.value); |
| break; |
| case YieldFrom_kind: |
| CALL(astfold_expr, expr_ty, node_->v.YieldFrom.value); |
| break; |
| case Compare_kind: |
| CALL(astfold_expr, expr_ty, node_->v.Compare.left); |
| CALL_SEQ(astfold_expr, expr_ty, node_->v.Compare.comparators); |
| CALL(fold_compare, expr_ty, node_); |
| break; |
| case Call_kind: |
| CALL(astfold_expr, expr_ty, node_->v.Call.func); |
| CALL_SEQ(astfold_expr, expr_ty, node_->v.Call.args); |
| CALL_SEQ(astfold_keyword, keyword_ty, node_->v.Call.keywords); |
| break; |
| case FormattedValue_kind: |
| CALL(astfold_expr, expr_ty, node_->v.FormattedValue.value); |
| CALL_OPT(astfold_expr, expr_ty, node_->v.FormattedValue.format_spec); |
| break; |
| case JoinedStr_kind: |
| CALL_SEQ(astfold_expr, expr_ty, node_->v.JoinedStr.values); |
| break; |
| case Attribute_kind: |
| CALL(astfold_expr, expr_ty, node_->v.Attribute.value); |
| break; |
| case Subscript_kind: |
| CALL(astfold_expr, expr_ty, node_->v.Subscript.value); |
| CALL(astfold_slice, slice_ty, node_->v.Subscript.slice); |
| CALL(fold_subscr, expr_ty, node_); |
| break; |
| case Starred_kind: |
| CALL(astfold_expr, expr_ty, node_->v.Starred.value); |
| break; |
| case List_kind: |
| CALL_SEQ(astfold_expr, expr_ty, node_->v.List.elts); |
| break; |
| case Tuple_kind: |
| CALL_SEQ(astfold_expr, expr_ty, node_->v.Tuple.elts); |
| CALL(fold_tuple, expr_ty, node_); |
| break; |
| default: |
| break; |
| } |
| return 1; |
| } |
| |
| static int |
| astfold_slice(slice_ty node_, PyArena* ctx_) |
| { |
| switch (node_->kind) { |
| case Slice_kind: |
| CALL_OPT(astfold_expr, expr_ty, node_->v.Slice.lower); |
| CALL_OPT(astfold_expr, expr_ty, node_->v.Slice.upper); |
| CALL_OPT(astfold_expr, expr_ty, node_->v.Slice.step); |
| break; |
| case ExtSlice_kind: |
| CALL_SEQ(astfold_slice, slice_ty, node_->v.ExtSlice.dims); |
| break; |
| case Index_kind: |
| CALL(astfold_expr, expr_ty, node_->v.Index.value); |
| break; |
| default: |
| break; |
| } |
| return 1; |
| } |
| |
| static int |
| astfold_keyword(keyword_ty node_, PyArena* ctx_) |
| { |
| CALL(astfold_expr, expr_ty, node_->value); |
| return 1; |
| } |
| |
| static int |
| astfold_comprehension(comprehension_ty node_, PyArena* ctx_) |
| { |
| CALL(astfold_expr, expr_ty, node_->target); |
| CALL(astfold_expr, expr_ty, node_->iter); |
| CALL_SEQ(astfold_expr, expr_ty, node_->ifs); |
| return 1; |
| } |
| |
| static int |
| astfold_arguments(arguments_ty node_, PyArena* ctx_) |
| { |
| CALL_SEQ(astfold_arg, arg_ty, node_->args); |
| CALL_OPT(astfold_arg, arg_ty, node_->vararg); |
| CALL_SEQ(astfold_arg, arg_ty, node_->kwonlyargs); |
| CALL_SEQ(astfold_expr, expr_ty, node_->kw_defaults); |
| CALL_OPT(astfold_arg, arg_ty, node_->kwarg); |
| CALL_SEQ(astfold_expr, expr_ty, node_->defaults); |
| return 1; |
| } |
| |
| static int |
| astfold_arg(arg_ty node_, PyArena* ctx_) |
| { |
| CALL_OPT(astfold_expr, expr_ty, node_->annotation); |
| return 1; |
| } |
| |
| static int |
| astfold_stmt(stmt_ty node_, PyArena* ctx_) |
| { |
| switch (node_->kind) { |
| case FunctionDef_kind: |
| CALL(astfold_arguments, arguments_ty, node_->v.FunctionDef.args); |
| CALL_SEQ(astfold_stmt, stmt_ty, node_->v.FunctionDef.body); |
| CALL_SEQ(astfold_expr, expr_ty, node_->v.FunctionDef.decorator_list); |
| CALL_OPT(astfold_expr, expr_ty, node_->v.FunctionDef.returns); |
| break; |
| case AsyncFunctionDef_kind: |
| CALL(astfold_arguments, arguments_ty, node_->v.AsyncFunctionDef.args); |
| CALL_SEQ(astfold_stmt, stmt_ty, node_->v.AsyncFunctionDef.body); |
| CALL_SEQ(astfold_expr, expr_ty, node_->v.AsyncFunctionDef.decorator_list); |
| CALL_OPT(astfold_expr, expr_ty, node_->v.AsyncFunctionDef.returns); |
| break; |
| case ClassDef_kind: |
| CALL_SEQ(astfold_expr, expr_ty, node_->v.ClassDef.bases); |
| CALL_SEQ(astfold_keyword, keyword_ty, node_->v.ClassDef.keywords); |
| CALL_SEQ(astfold_stmt, stmt_ty, node_->v.ClassDef.body); |
| CALL_SEQ(astfold_expr, expr_ty, node_->v.ClassDef.decorator_list); |
| break; |
| case Return_kind: |
| CALL_OPT(astfold_expr, expr_ty, node_->v.Return.value); |
| break; |
| case Delete_kind: |
| CALL_SEQ(astfold_expr, expr_ty, node_->v.Delete.targets); |
| break; |
| case Assign_kind: |
| CALL_SEQ(astfold_expr, expr_ty, node_->v.Assign.targets); |
| CALL(astfold_expr, expr_ty, node_->v.Assign.value); |
| break; |
| case AugAssign_kind: |
| CALL(astfold_expr, expr_ty, node_->v.AugAssign.target); |
| CALL(astfold_expr, expr_ty, node_->v.AugAssign.value); |
| break; |
| case AnnAssign_kind: |
| CALL(astfold_expr, expr_ty, node_->v.AnnAssign.target); |
| CALL(astfold_expr, expr_ty, node_->v.AnnAssign.annotation); |
| CALL_OPT(astfold_expr, expr_ty, node_->v.AnnAssign.value); |
| break; |
| case For_kind: |
| CALL(astfold_expr, expr_ty, node_->v.For.target); |
| CALL(astfold_expr, expr_ty, node_->v.For.iter); |
| CALL_SEQ(astfold_stmt, stmt_ty, node_->v.For.body); |
| CALL_SEQ(astfold_stmt, stmt_ty, node_->v.For.orelse); |
| break; |
| case AsyncFor_kind: |
| CALL(astfold_expr, expr_ty, node_->v.AsyncFor.target); |
| CALL(astfold_expr, expr_ty, node_->v.AsyncFor.iter); |
| CALL_SEQ(astfold_stmt, stmt_ty, node_->v.AsyncFor.body); |
| CALL_SEQ(astfold_stmt, stmt_ty, node_->v.AsyncFor.orelse); |
| break; |
| case While_kind: |
| CALL(astfold_expr, expr_ty, node_->v.While.test); |
| CALL_SEQ(astfold_stmt, stmt_ty, node_->v.While.body); |
| CALL_SEQ(astfold_stmt, stmt_ty, node_->v.While.orelse); |
| break; |
| case If_kind: |
| CALL(astfold_expr, expr_ty, node_->v.If.test); |
| CALL_SEQ(astfold_stmt, stmt_ty, node_->v.If.body); |
| CALL_SEQ(astfold_stmt, stmt_ty, node_->v.If.orelse); |
| break; |
| case With_kind: |
| CALL_SEQ(astfold_withitem, withitem_ty, node_->v.With.items); |
| CALL_SEQ(astfold_stmt, stmt_ty, node_->v.With.body); |
| break; |
| case AsyncWith_kind: |
| CALL_SEQ(astfold_withitem, withitem_ty, node_->v.AsyncWith.items); |
| CALL_SEQ(astfold_stmt, stmt_ty, node_->v.AsyncWith.body); |
| break; |
| case Raise_kind: |
| CALL_OPT(astfold_expr, expr_ty, node_->v.Raise.exc); |
| CALL_OPT(astfold_expr, expr_ty, node_->v.Raise.cause); |
| break; |
| case Try_kind: |
| CALL_SEQ(astfold_stmt, stmt_ty, node_->v.Try.body); |
| CALL_SEQ(astfold_excepthandler, excepthandler_ty, node_->v.Try.handlers); |
| CALL_SEQ(astfold_stmt, stmt_ty, node_->v.Try.orelse); |
| CALL_SEQ(astfold_stmt, stmt_ty, node_->v.Try.finalbody); |
| break; |
| case Assert_kind: |
| CALL(astfold_expr, expr_ty, node_->v.Assert.test); |
| CALL_OPT(astfold_expr, expr_ty, node_->v.Assert.msg); |
| break; |
| case Expr_kind: |
| CALL(astfold_expr, expr_ty, node_->v.Expr.value); |
| break; |
| default: |
| break; |
| } |
| return 1; |
| } |
| |
| static int |
| astfold_excepthandler(excepthandler_ty node_, PyArena* ctx_) |
| { |
| switch (node_->kind) { |
| case ExceptHandler_kind: |
| CALL_OPT(astfold_expr, expr_ty, node_->v.ExceptHandler.type); |
| CALL_SEQ(astfold_stmt, stmt_ty, node_->v.ExceptHandler.body); |
| break; |
| default: |
| break; |
| } |
| return 1; |
| } |
| |
| static int |
| astfold_withitem(withitem_ty node_, PyArena* ctx_) |
| { |
| CALL(astfold_expr, expr_ty, node_->context_expr); |
| CALL_OPT(astfold_expr, expr_ty, node_->optional_vars); |
| return 1; |
| } |
| |
| #undef CALL |
| #undef CALL_OPT |
| #undef CALL_SEQ |
| #undef CALL_INT_SEQ |
| |
| int |
| _PyAST_Optimize(mod_ty mod, PyArena *arena) |
| { |
| int ret = astfold_mod(mod, arena); |
| assert(ret || PyErr_Occurred()); |
| return ret; |
| } |