Commit 0efb3a1b authored by Damien's avatar Damien
Browse files

Tidy up SMALL_INT optimisations and CPython compatibility.

parent 3a205179
......@@ -88,7 +88,10 @@ py_parse_node_t fold_constants(py_parse_node_t pn) {
int arg0 = PY_PARSE_NODE_LEAF_ARG(pns->nodes[0]);
int arg1 = PY_PARSE_NODE_LEAF_ARG(pns->nodes[2]);
if (PY_PARSE_NODE_IS_TOKEN_KIND(pns->nodes[1], PY_TOKEN_OP_DBL_LESS)) {
pn = py_parse_node_new_leaf(PY_PARSE_NODE_SMALL_INT, arg0 << arg1); // XXX can overflow; enabled only to compare with CPython
#if defined(MICROPY_EMIT_ENABLE_CPYTHON)
// can overflow; enabled only to compare with CPython
pn = py_parse_node_new_leaf(PY_PARSE_NODE_SMALL_INT, arg0 << arg1);
#endif
} else if (PY_PARSE_NODE_IS_TOKEN_KIND(pns->nodes[1], PY_TOKEN_OP_DBL_MORE)) {
pn = py_parse_node_new_leaf(PY_PARSE_NODE_SMALL_INT, arg0 >> arg1);
} else {
......@@ -99,32 +102,43 @@ py_parse_node_t fold_constants(py_parse_node_t pn) {
break;
case PN_arith_expr:
// XXX can overflow; enabled only to compare with CPython
// overflow checking here relies on SMALL_INT being strictly smaller than machine_int_t
if (n == 3 && PY_PARSE_NODE_IS_SMALL_INT(pns->nodes[0]) && PY_PARSE_NODE_IS_SMALL_INT(pns->nodes[2])) {
int arg0 = PY_PARSE_NODE_LEAF_ARG(pns->nodes[0]);
int arg1 = PY_PARSE_NODE_LEAF_ARG(pns->nodes[2]);
machine_int_t arg0 = PY_PARSE_NODE_LEAF_ARG(pns->nodes[0]);
machine_int_t arg1 = PY_PARSE_NODE_LEAF_ARG(pns->nodes[2]);
machine_int_t res;
if (PY_PARSE_NODE_IS_TOKEN_KIND(pns->nodes[1], PY_TOKEN_OP_PLUS)) {
pn = py_parse_node_new_leaf(PY_PARSE_NODE_SMALL_INT, arg0 + arg1);
res = arg0 + arg1;
} else if (PY_PARSE_NODE_IS_TOKEN_KIND(pns->nodes[1], PY_TOKEN_OP_MINUS)) {
pn = py_parse_node_new_leaf(PY_PARSE_NODE_SMALL_INT, arg0 - arg1);
res = arg0 - arg1;
} else {
// shouldn't happen
assert(0);
res = 0;
}
if (PY_FIT_SMALL_INT(res)) {
pn = py_parse_node_new_leaf(PY_PARSE_NODE_SMALL_INT, res);
}
}
break;
case PN_term:
// XXX can overflow; enabled only to compare with CPython
if (n == 3 && PY_PARSE_NODE_IS_SMALL_INT(pns->nodes[0]) && PY_PARSE_NODE_IS_SMALL_INT(pns->nodes[2])) {
int arg0 = PY_PARSE_NODE_LEAF_ARG(pns->nodes[0]);
int arg1 = PY_PARSE_NODE_LEAF_ARG(pns->nodes[2]);
if (PY_PARSE_NODE_IS_TOKEN_KIND(pns->nodes[1], PY_TOKEN_OP_STAR)) {
#if defined(MICROPY_EMIT_ENABLE_CPYTHON)
// can overflow; enabled only to compare with CPython
pn = py_parse_node_new_leaf(PY_PARSE_NODE_SMALL_INT, arg0 * arg1);
#endif
} else if (PY_PARSE_NODE_IS_TOKEN_KIND(pns->nodes[1], PY_TOKEN_OP_SLASH)) {
; // pass
//} else if (PY_PARSE_NODE_IS_TOKEN_KIND(pns->nodes[1], PY_TOKEN_OP_)) {
//pn = py_parse_node_new_leaf(PY_PARSE_NODE_SMALL_INT, arg0 - arg1);
} else if (PY_PARSE_NODE_IS_TOKEN_KIND(pns->nodes[1], PY_TOKEN_OP_PERCENT)) {
// XXX implement this properly as Python's % operator acts differently to C's
pn = py_parse_node_new_leaf(PY_PARSE_NODE_SMALL_INT, arg0 % arg1);
} else if (PY_PARSE_NODE_IS_TOKEN_KIND(pns->nodes[1], PY_TOKEN_OP_DBL_SLASH)) {
// XXX implement this properly as Python's // operator acts differently to C's
pn = py_parse_node_new_leaf(PY_PARSE_NODE_SMALL_INT, arg0 / arg1);
} else {
// shouldn't happen
assert(0);
......@@ -148,8 +162,9 @@ py_parse_node_t fold_constants(py_parse_node_t pn) {
}
break;
#if defined(MICROPY_EMIT_ENABLE_CPYTHON)
case PN_power:
// XXX can overflow; enabled only to compare with CPython
// can overflow; enabled only to compare with CPython
if (PY_PARSE_NODE_IS_SMALL_INT(pns->nodes[0]) && PY_PARSE_NODE_IS_NULL(pns->nodes[1]) && !PY_PARSE_NODE_IS_NULL(pns->nodes[2])) {
py_parse_node_struct_t* pns2 = (py_parse_node_struct_t*)pns->nodes[2];
if (PY_PARSE_NODE_IS_SMALL_INT(pns2->nodes[0])) {
......@@ -165,6 +180,7 @@ py_parse_node_t fold_constants(py_parse_node_t pn) {
}
}
break;
#endif
}
}
......
......@@ -228,7 +228,7 @@ static void push_result_token(parser_t *parser, const py_lexer_t *lex) {
}
if (dec) {
pn = py_parse_node_new_leaf(PY_PARSE_NODE_DECIMAL, qstr_from_strn_copy(str, len));
} else if (small_int && -0x800000 <= int_val && int_val <= 0x7fffff) { // XXX check this range formula!
} else if (small_int && PY_FIT_SMALL_INT(int_val)) {
pn = py_parse_node_new_leaf(PY_PARSE_NODE_SMALL_INT, int_val);
} else {
pn = py_parse_node_new_leaf(PY_PARSE_NODE_INTEGER, qstr_from_strn_copy(str, len));
......
......@@ -11,6 +11,11 @@ struct _py_lexer_t;
// - xxxx...1101: a token; bits 4 and above are py_token_kind_t
// - xxxx...xxx0: pointer to py_parse_node_struct_t
// makes sure the top 5 bits of x are all cleared (positive number) or all set (negavite number)
// these macros can probably go somewhere else because they are used more than just in the parser
#define PY_UINT_HIGH_5_BITS (~((~((machine_uint_t)0)) >> 5))
#define PY_FIT_SMALL_INT(x) (((((machine_uint_t)(x)) & PY_UINT_HIGH_5_BITS) == 0) || ((((machine_uint_t)(x)) & PY_UINT_HIGH_5_BITS) == PY_UINT_HIGH_5_BITS))
#define PY_PARSE_NODE_NULL (0)
#define PY_PARSE_NODE_ID (0x1)
#define PY_PARSE_NODE_SMALL_INT (0x3)
......
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