Commit 495d781a authored by Damien George's avatar Damien George
Browse files

py: implement UNPACK_EX byte code (for: a, *b, c = d)

parent e753d916
...@@ -1933,6 +1933,11 @@ void compile_expr_stmt(compiler_t *comp, mp_parse_node_struct_t *pns) { ...@@ -1933,6 +1933,11 @@ void compile_expr_stmt(compiler_t *comp, mp_parse_node_struct_t *pns) {
// optimisation for a, b = c, d; to match CPython's optimisation // optimisation for a, b = c, d; to match CPython's optimisation
mp_parse_node_struct_t* pns10 = (mp_parse_node_struct_t*)pns1->nodes[0]; mp_parse_node_struct_t* pns10 = (mp_parse_node_struct_t*)pns1->nodes[0];
mp_parse_node_struct_t* pns0 = (mp_parse_node_struct_t*)pns->nodes[0]; mp_parse_node_struct_t* pns0 = (mp_parse_node_struct_t*)pns->nodes[0];
if (MP_PARSE_NODE_IS_STRUCT_KIND(pns0->nodes[0], PN_star_expr)
|| MP_PARSE_NODE_IS_STRUCT_KIND(pns0->nodes[1], PN_star_expr)) {
// can't optimise when it's a star expression on the lhs
goto no_optimisation;
}
compile_node(comp, pns10->nodes[0]); // rhs compile_node(comp, pns10->nodes[0]); // rhs
compile_node(comp, pns10->nodes[1]); // rhs compile_node(comp, pns10->nodes[1]); // rhs
EMIT(rot_two); EMIT(rot_two);
...@@ -1945,6 +1950,12 @@ void compile_expr_stmt(compiler_t *comp, mp_parse_node_struct_t *pns) { ...@@ -1945,6 +1950,12 @@ void compile_expr_stmt(compiler_t *comp, mp_parse_node_struct_t *pns) {
// optimisation for a, b, c = d, e, f; to match CPython's optimisation // optimisation for a, b, c = d, e, f; to match CPython's optimisation
mp_parse_node_struct_t* pns10 = (mp_parse_node_struct_t*)pns1->nodes[0]; mp_parse_node_struct_t* pns10 = (mp_parse_node_struct_t*)pns1->nodes[0];
mp_parse_node_struct_t* pns0 = (mp_parse_node_struct_t*)pns->nodes[0]; mp_parse_node_struct_t* pns0 = (mp_parse_node_struct_t*)pns->nodes[0];
if (MP_PARSE_NODE_IS_STRUCT_KIND(pns0->nodes[0], PN_star_expr)
|| MP_PARSE_NODE_IS_STRUCT_KIND(pns0->nodes[1], PN_star_expr)
|| MP_PARSE_NODE_IS_STRUCT_KIND(pns0->nodes[2], PN_star_expr)) {
// can't optimise when it's a star expression on the lhs
goto no_optimisation;
}
compile_node(comp, pns10->nodes[0]); // rhs compile_node(comp, pns10->nodes[0]); // rhs
compile_node(comp, pns10->nodes[1]); // rhs compile_node(comp, pns10->nodes[1]); // rhs
compile_node(comp, pns10->nodes[2]); // rhs compile_node(comp, pns10->nodes[2]); // rhs
...@@ -1954,6 +1965,7 @@ void compile_expr_stmt(compiler_t *comp, mp_parse_node_struct_t *pns) { ...@@ -1954,6 +1965,7 @@ void compile_expr_stmt(compiler_t *comp, mp_parse_node_struct_t *pns) {
c_assign(comp, pns0->nodes[1], ASSIGN_STORE); // lhs store c_assign(comp, pns0->nodes[1], ASSIGN_STORE); // lhs store
c_assign(comp, pns0->nodes[2], ASSIGN_STORE); // lhs store c_assign(comp, pns0->nodes[2], ASSIGN_STORE); // lhs store
} else { } else {
no_optimisation:
compile_node(comp, pns1->nodes[0]); // rhs compile_node(comp, pns1->nodes[0]); // rhs
c_assign(comp, pns->nodes[0], ASSIGN_STORE); // lhs store c_assign(comp, pns->nodes[0], ASSIGN_STORE); // lhs store
} }
......
...@@ -440,6 +440,7 @@ mp_obj_t mp_obj_tuple_make_new(mp_obj_t type_in, uint n_args, uint n_kw, const m ...@@ -440,6 +440,7 @@ mp_obj_t mp_obj_tuple_make_new(mp_obj_t type_in, uint n_args, uint n_kw, const m
// list // list
mp_obj_t mp_obj_list_append(mp_obj_t self_in, mp_obj_t arg); mp_obj_t mp_obj_list_append(mp_obj_t self_in, mp_obj_t arg);
void mp_obj_list_get(mp_obj_t self_in, uint *len, mp_obj_t **items); void mp_obj_list_get(mp_obj_t self_in, uint *len, mp_obj_t **items);
void mp_obj_list_set_len(mp_obj_t self_in, uint len);
void mp_obj_list_store(mp_obj_t self_in, mp_obj_t index, mp_obj_t value); void mp_obj_list_store(mp_obj_t self_in, mp_obj_t index, mp_obj_t value);
mp_obj_t mp_obj_list_sort(uint n_args, const mp_obj_t *args, mp_map_t *kwargs); mp_obj_t mp_obj_list_sort(uint n_args, const mp_obj_t *args, mp_map_t *kwargs);
......
...@@ -378,6 +378,13 @@ void mp_obj_list_get(mp_obj_t self_in, uint *len, mp_obj_t **items) { ...@@ -378,6 +378,13 @@ void mp_obj_list_get(mp_obj_t self_in, uint *len, mp_obj_t **items) {
*items = self->items; *items = self->items;
} }
void mp_obj_list_set_len(mp_obj_t self_in, uint len) {
// trust that the caller knows what it's doing
// TODO realloc if len got much smaller than alloc
mp_obj_list_t *self = self_in;
self->len = len;
}
void mp_obj_list_store(mp_obj_t self_in, mp_obj_t index, mp_obj_t value) { void mp_obj_list_store(mp_obj_t self_in, mp_obj_t index, mp_obj_t value) {
mp_obj_list_t *self = self_in; mp_obj_list_t *self = self_in;
uint i = mp_get_index(self->base.type, self->len, index, false); uint i = mp_get_index(self->base.type, self->len, index, false);
......
...@@ -672,6 +672,70 @@ too_long: ...@@ -672,6 +672,70 @@ too_long:
nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_ValueError, "too many values to unpack (expected %d)", num)); nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_ValueError, "too many values to unpack (expected %d)", num));
} }
// unpacked items are stored in reverse order into the array pointed to by items
void mp_unpack_ex(mp_obj_t seq_in, uint num_in, mp_obj_t *items) {
uint num_left = num_in & 0xff;
uint num_right = (num_in >> 8) & 0xff;
DEBUG_OP_printf("unpack ex %d %d\n", num_left, num_right);
uint seq_len;
if (MP_OBJ_IS_TYPE(seq_in, &mp_type_tuple) || MP_OBJ_IS_TYPE(seq_in, &mp_type_list)) {
mp_obj_t *seq_items;
if (MP_OBJ_IS_TYPE(seq_in, &mp_type_tuple)) {
mp_obj_tuple_get(seq_in, &seq_len, &seq_items);
} else {
if (num_left == 0 && num_right == 0) {
// *a, = b # sets a to b if b is a list
items[0] = seq_in;
return;
}
mp_obj_list_get(seq_in, &seq_len, &seq_items);
}
if (seq_len < num_left + num_right) {
goto too_short;
}
for (uint i = 0; i < num_right; i++) {
items[i] = seq_items[seq_len - 1 - i];
}
items[num_right] = mp_obj_new_list(seq_len - num_left - num_right, seq_items + num_left);
for (uint i = 0; i < num_left; i++) {
items[num_right + 1 + i] = seq_items[num_left - 1 - i];
}
} else {
// Generic iterable; this gets a bit messy: we unpack known left length to the
// items destination array, then the rest to a dynamically created list. Once the
// iterable is exhausted, we take from this list for the right part of the items.
// TODO Improve to waste less memory in the dynamically created list.
mp_obj_t iterable = mp_getiter(seq_in);
mp_obj_t item;
for (seq_len = 0; seq_len < num_left; seq_len++) {
item = mp_iternext(iterable);
if (item == MP_OBJ_NULL) {
goto too_short;
}
items[num_left + num_right + 1 - 1 - seq_len] = item;
}
mp_obj_t rest = mp_obj_new_list(0, NULL);
while ((item = mp_iternext(iterable)) != MP_OBJ_NULL) {
mp_obj_list_append(rest, item);
}
uint rest_len;
mp_obj_t *rest_items;
mp_obj_list_get(rest, &rest_len, &rest_items);
if (rest_len < num_right) {
goto too_short;
}
items[num_right] = rest;
for (uint i = 0; i < num_right; i++) {
items[num_right - 1 - i] = rest_items[rest_len - num_right + i];
}
mp_obj_list_set_len(rest, rest_len - num_right);
}
return;
too_short:
nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_ValueError, "need more than %d values to unpack", seq_len));
}
mp_obj_t mp_load_attr(mp_obj_t base, qstr attr) { mp_obj_t mp_load_attr(mp_obj_t base, qstr attr) {
DEBUG_OP_printf("load attr %p.%s\n", base, qstr_str(attr)); DEBUG_OP_printf("load attr %p.%s\n", base, qstr_str(attr));
// use load_method // use load_method
......
...@@ -44,6 +44,7 @@ mp_obj_t mp_call_method_n_kw(uint n_args, uint n_kw, const mp_obj_t *args); ...@@ -44,6 +44,7 @@ mp_obj_t mp_call_method_n_kw(uint n_args, uint n_kw, const mp_obj_t *args);
mp_obj_t mp_call_method_n_kw_var(bool have_self, uint n_args_n_kw, const mp_obj_t *args); mp_obj_t mp_call_method_n_kw_var(bool have_self, uint n_args_n_kw, const mp_obj_t *args);
void mp_unpack_sequence(mp_obj_t seq, uint num, mp_obj_t *items); void mp_unpack_sequence(mp_obj_t seq, uint num, mp_obj_t *items);
void mp_unpack_ex(mp_obj_t seq, uint num, mp_obj_t *items);
mp_obj_t mp_store_map(mp_obj_t map, mp_obj_t key, mp_obj_t value); mp_obj_t mp_store_map(mp_obj_t map, mp_obj_t key, mp_obj_t value);
mp_obj_t mp_load_attr(mp_obj_t base, qstr attr); mp_obj_t mp_load_attr(mp_obj_t base, qstr attr);
void mp_load_method(mp_obj_t base, qstr attr, mp_obj_t *dest); void mp_load_method(mp_obj_t base, qstr attr, mp_obj_t *dest);
......
...@@ -653,6 +653,12 @@ unwind_jump: ...@@ -653,6 +653,12 @@ unwind_jump:
sp += unum - 1; sp += unum - 1;
break; break;
case MP_BC_UNPACK_EX:
DECODE_UINT;
mp_unpack_ex(sp[0], unum, sp);
sp += (unum & 0xff) + ((unum >> 8) & 0xff);
break;
case MP_BC_MAKE_FUNCTION: case MP_BC_MAKE_FUNCTION:
DECODE_UINT; DECODE_UINT;
PUSH(mp_make_function_from_id(unum, MP_OBJ_NULL, MP_OBJ_NULL)); PUSH(mp_make_function_from_id(unum, MP_OBJ_NULL, MP_OBJ_NULL));
......
# unpack sequences
a, = 1, ; print(a)
a, b = 2, 3 ; print(a, b)
a, b = range(2); print(a, b)
# with star
*a, = () ; print(a)
*a, = 4, ; print(a)
*a, = 5, 6 ; print(a)
*a, b = 7, ; print(a, b)
*a, b = 8, 9 ; print(a, b)
*a, b = 10, 11, 12 ; print(a, b)
a, *b = 13, ; print(a, b)
a, *b = 14, 15 ; print(a, b)
a, *b = 16, 17, 18 ; print(a, b)
a, *b, c = 19, 20 ; print(a, b)
a, *b, c = 21, 22, 23 ; print(a, b)
a, *b, c = 24, 25, 26, 27 ; print(a, b)
a = [28, 29]
*b, = a
print(a, b, a == b)
try:
a, *b, c = (30,)
except ValueError:
print("ValueError")
# with star and generic iterator
*a, = range(5) ; print(a)
*a, b = range(5) ; print(a, b)
*a, b, c = range(5) ; print(a, b, c)
a, *b = range(5) ; print(a, b)
a, *b, c = range(5) ; print(a, b, c)
a, *b, c, d = range(5) ; print(a, b, c, d)
a, b, *c = range(5) ; print(a, b, c)
a, b, *c, d = range(5) ; print(a, b, c, d)
a, b, *c, d, e = range(5) ; print(a, b, c, d, e)
*a, = [x * 2 for x in [1, 2, 3, 4]] ; print(a)
*a, b = [x * 2 for x in [1, 2, 3, 4]] ; print(a, b)
a, *b = [x * 2 for x in [1, 2, 3, 4]] ; print(a, b)
a, *b, c = [x * 2 for x in [1, 2, 3, 4]]; print(a, b, c)
try:
a, *b, c = range(0)
except ValueError:
print("ValueError")
try:
a, *b, c = range(1)
except ValueError:
print("ValueError")
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