From c18d83118881333b9a0afd0add83afb2ba7300f7 Mon Sep 17 00:00:00 2001 From: Dennis Sweeney <36520290+sweeneyde@users.noreply.github.com> Date: Tue, 20 Dec 2022 15:46:16 -0500 Subject: [PATCH] gh-100188: Reduce misses in BINARY_SUBSCR_(LIST/TUPLE)_INT (#100189) Don't specialize if the index is negative. --- ...022-12-12-05-30-12.gh-issue-100188.sGCSMR.rst | 3 +++ Python/specialize.c | 16 ++++++++++++---- 2 files changed, 15 insertions(+), 4 deletions(-) create mode 100644 Misc/NEWS.d/next/Core and Builtins/2022-12-12-05-30-12.gh-issue-100188.sGCSMR.rst diff --git a/Misc/NEWS.d/next/Core and Builtins/2022-12-12-05-30-12.gh-issue-100188.sGCSMR.rst b/Misc/NEWS.d/next/Core and Builtins/2022-12-12-05-30-12.gh-issue-100188.sGCSMR.rst new file mode 100644 index 00000000000..ec62fbd582f --- /dev/null +++ b/Misc/NEWS.d/next/Core and Builtins/2022-12-12-05-30-12.gh-issue-100188.sGCSMR.rst @@ -0,0 +1,3 @@ +The ``BINARY_SUBSCR_LIST_INT`` and ``BINARY_SUBSCR_TUPLE_INT`` +instructions are no longer used for negative integers because +those instructions always miss when encountering negative integers. diff --git a/Python/specialize.c b/Python/specialize.c index a1666ccc915..c6c50271647 100644 --- a/Python/specialize.c +++ b/Python/specialize.c @@ -1302,8 +1302,12 @@ _Py_Specialize_BinarySubscr( PyTypeObject *container_type = Py_TYPE(container); if (container_type == &PyList_Type) { if (PyLong_CheckExact(sub)) { - _py_set_opcode(instr, BINARY_SUBSCR_LIST_INT); - goto success; + if (Py_SIZE(sub) == 0 || Py_SIZE(sub) == 1) { + _py_set_opcode(instr, BINARY_SUBSCR_LIST_INT); + goto success; + } + SPECIALIZATION_FAIL(BINARY_SUBSCR, SPEC_FAIL_OUT_OF_RANGE); + goto fail; } SPECIALIZATION_FAIL(BINARY_SUBSCR, PySlice_Check(sub) ? SPEC_FAIL_SUBSCR_LIST_SLICE : SPEC_FAIL_OTHER); @@ -1311,8 +1315,12 @@ _Py_Specialize_BinarySubscr( } if (container_type == &PyTuple_Type) { if (PyLong_CheckExact(sub)) { - _py_set_opcode(instr, BINARY_SUBSCR_TUPLE_INT); - goto success; + if (Py_SIZE(sub) == 0 || Py_SIZE(sub) == 1) { + _py_set_opcode(instr, BINARY_SUBSCR_TUPLE_INT); + goto success; + } + SPECIALIZATION_FAIL(BINARY_SUBSCR, SPEC_FAIL_OUT_OF_RANGE); + goto fail; } SPECIALIZATION_FAIL(BINARY_SUBSCR, PySlice_Check(sub) ? SPEC_FAIL_SUBSCR_TUPLE_SLICE : SPEC_FAIL_OTHER);