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bpo-38328: Speed up the creation time of constant list and set displa… · python/cpython@6dd9b64

3 files changed

lines changed

Original file line numberDiff line numberDiff line change

@@ -1222,7 +1222,7 @@ def get_gen(): yield 1

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# list

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samples = [[], [1,2,3], ['1', '2', '3']]

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for sample in samples:

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check(sample, vsize('Pn') + len(sample)*self.P)

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check(list(sample), vsize('Pn') + len(sample)*self.P)

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# sortwrapper (list)

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# XXX

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# cmpwrapper (list)

Original file line numberDiff line numberDiff line change

@@ -0,0 +1,2 @@

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Sped up the creation time of constant :class:`list` and :class:`set` displays.

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Patch by Brandt Bucher.

Original file line numberDiff line numberDiff line change

@@ -197,6 +197,7 @@ static int compiler_visit_slice(struct compiler *, slice_ty,

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expr_context_ty);

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static int inplace_binop(struct compiler *, operator_ty);

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static int are_all_items_const(asdl_seq *, Py_ssize_t, Py_ssize_t);

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static int expr_constant(expr_ty);

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static int compiler_with(struct compiler *, stmt_ty, int);

@@ -3655,6 +3656,27 @@ starunpack_helper(struct compiler *c, asdl_seq *elts,

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{

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Py_ssize_t n = asdl_seq_LEN(elts);

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Py_ssize_t i, nsubitems = 0, nseen = 0;

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if (n > 2 && are_all_items_const(elts, 0, n)) {

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PyObject *folded = PyTuple_New(n);

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if (folded == NULL) {

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return 0;

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}

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PyObject *val;

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for (i = 0; i < n; i++) {

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val = ((expr_ty)asdl_seq_GET(elts, i))->v.Constant.value;

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Py_INCREF(val);

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PyTuple_SET_ITEM(folded, i, val);

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}

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if (outer_op == BUILD_SET_UNPACK) {

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Py_SETREF(folded, PyFrozenSet_New(folded));

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if (folded == NULL) {

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return 0;

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}

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}

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ADDOP_LOAD_CONST_NEW(c, folded);

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ADDOP_I(c, outer_op, 1);

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return 1;

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}

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for (i = 0; i < n; i++) {

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expr_ty elt = asdl_seq_GET(elts, i);

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if (elt->kind == Starred_kind) {