From a52d2528a405c1e2bfeb6470cb3313a5338dc45f Mon Sep 17 00:00:00 2001 From: Dennis Sweeney <36520290+sweeneyde@users.noreply.github.com> Date: Thu, 24 Feb 2022 09:55:59 -0500 Subject: [PATCH] bpo-46823: Implement LOAD_FAST__LOAD_ATTR_INSTANCE_VALUE superinstruction (GH-31484) --- Include/opcode.h | 1 + Lib/opcode.py | 1 + .../2022-02-22-05-14-25.bpo-46823.z9NZC9.rst | 1 + Python/ceval.c | 80 ++++++++++++++++++- Python/opcode_targets.h | 2 +- Python/specialize.c | 10 +++ 6 files changed, 91 insertions(+), 4 deletions(-) create mode 100644 Misc/NEWS.d/next/Core and Builtins/2022-02-22-05-14-25.bpo-46823.z9NZC9.rst diff --git a/Include/opcode.h b/Include/opcode.h index 7820af64829..50153c19e9b 100644 --- a/Include/opcode.h +++ b/Include/opcode.h @@ -181,6 +181,7 @@ extern "C" { #define LOAD_FAST__LOAD_CONST 169 #define LOAD_CONST__LOAD_FAST 170 #define STORE_FAST__STORE_FAST 173 +#define LOAD_FAST__LOAD_ATTR_INSTANCE_VALUE 174 #define DO_TRACING 255 #ifdef NEED_OPCODE_JUMP_TABLES static uint32_t _PyOpcode_RelativeJump[8] = { diff --git a/Lib/opcode.py b/Lib/opcode.py index 0c859c16b71..71a9347deba 100644 --- a/Lib/opcode.py +++ b/Lib/opcode.py @@ -295,6 +295,7 @@ _specialized_instructions = [ "LOAD_FAST__LOAD_CONST", "LOAD_CONST__LOAD_FAST", "STORE_FAST__STORE_FAST", + "LOAD_FAST__LOAD_ATTR_INSTANCE_VALUE", ] _specialization_stats = [ "success", diff --git a/Misc/NEWS.d/next/Core and Builtins/2022-02-22-05-14-25.bpo-46823.z9NZC9.rst b/Misc/NEWS.d/next/Core and Builtins/2022-02-22-05-14-25.bpo-46823.z9NZC9.rst new file mode 100644 index 00000000000..908f48d33f2 --- /dev/null +++ b/Misc/NEWS.d/next/Core and Builtins/2022-02-22-05-14-25.bpo-46823.z9NZC9.rst @@ -0,0 +1 @@ +Implement a specialized combined opcode ``LOAD_FAST__LOAD_ATTR_INSTANCE_VALUE``. Patch by Dennis Sweeney. diff --git a/Python/ceval.c b/Python/ceval.c index 80775701902..f3bdaf13770 100644 --- a/Python/ceval.c +++ b/Python/ceval.c @@ -3444,6 +3444,34 @@ handle_eval_breaker: } } + TARGET(LOAD_FAST__LOAD_ATTR_INSTANCE_VALUE) { + assert(cframe.use_tracing == 0); + PyObject *owner = GETLOCAL(oparg); // borrowed + if (owner == NULL) { + goto unbound_local_error; + } + // GET_CACHE(), but for the following opcode + assert(_Py_OPCODE(*next_instr) == LOAD_ATTR_INSTANCE_VALUE); + SpecializedCacheEntry *caches = _GetSpecializedCacheEntryForInstruction( + first_instr, INSTR_OFFSET() + 1, _Py_OPARG(*next_instr)); + _PyAdaptiveEntry *cache0 = &caches[0].adaptive; + assert(cache0->version != 0); + PyTypeObject *tp = Py_TYPE(owner); + // These DEOPT_IF miss branches do PUSH(Py_NewRef(owner)). + DEOPT_IF(tp->tp_version_tag != cache0->version, + LOAD_FAST__LOAD_ATTR_INSTANCE_VALUE); + assert(tp->tp_dictoffset < 0); + assert(tp->tp_flags & Py_TPFLAGS_MANAGED_DICT); + PyDictValues *values = *_PyObject_ValuesPointer(owner); + DEOPT_IF(values == NULL, LOAD_FAST__LOAD_ATTR_INSTANCE_VALUE); + PyObject *res = values->values[cache0->index]; + DEOPT_IF(res == NULL, LOAD_FAST__LOAD_ATTR_INSTANCE_VALUE); + STAT_INC(LOAD_ATTR, hit); + PUSH(Py_NewRef(res)); + next_instr++; + NOTRACE_DISPATCH(); + } + TARGET(LOAD_ATTR_INSTANCE_VALUE) { assert(cframe.use_tracing == 0); PyObject *owner = TOP(); @@ -3452,13 +3480,13 @@ handle_eval_breaker: SpecializedCacheEntry *caches = GET_CACHE(); _PyAdaptiveEntry *cache0 = &caches[0].adaptive; assert(cache0->version != 0); - DEOPT_IF(tp->tp_version_tag != cache0->version, LOAD_ATTR); + DEOPT_IF(tp->tp_version_tag != cache0->version, LOAD_ATTR_INSTANCE_VALUE); assert(tp->tp_dictoffset < 0); assert(tp->tp_flags & Py_TPFLAGS_MANAGED_DICT); PyDictValues *values = *_PyObject_ValuesPointer(owner); - DEOPT_IF(values == NULL, LOAD_ATTR); + DEOPT_IF(values == NULL, LOAD_ATTR_INSTANCE_VALUE); res = values->values[cache0->index]; - DEOPT_IF(res == NULL, LOAD_ATTR); + DEOPT_IF(res == NULL, LOAD_ATTR_INSTANCE_VALUE); STAT_INC(LOAD_ATTR, hit); Py_INCREF(res); SET_TOP(res); @@ -5515,6 +5543,52 @@ MISS_WITH_CACHE(BINARY_SUBSCR) MISS_WITH_CACHE(UNPACK_SEQUENCE) MISS_WITH_OPARG_COUNTER(STORE_SUBSCR) +LOAD_ATTR_INSTANCE_VALUE_miss: + { + // Special-cased so that if LOAD_ATTR_INSTANCE_VALUE + // gets replaced, then any preceeding + // LOAD_FAST__LOAD_ATTR_INSTANCE_VALUE gets replaced as well + STAT_INC(LOAD_ATTR_INSTANCE_VALUE, miss); + STAT_INC(LOAD_ATTR, miss); + _PyAdaptiveEntry *cache = &GET_CACHE()->adaptive; + cache->counter--; + if (cache->counter == 0) { + next_instr[-1] = _Py_MAKECODEUNIT(LOAD_ATTR_ADAPTIVE, _Py_OPARG(next_instr[-1])); + if (_Py_OPCODE(next_instr[-2]) == LOAD_FAST__LOAD_ATTR_INSTANCE_VALUE) { + next_instr[-2] = _Py_MAKECODEUNIT(LOAD_FAST, _Py_OPARG(next_instr[-2])); + if (_Py_OPCODE(next_instr[-3]) == LOAD_FAST) { + next_instr[-3] = _Py_MAKECODEUNIT(LOAD_FAST__LOAD_FAST, _Py_OPARG(next_instr[-3])); + } + } + STAT_INC(LOAD_ATTR, deopt); + cache_backoff(cache); + } + oparg = cache->original_oparg; + JUMP_TO_INSTRUCTION(LOAD_ATTR); + } + +LOAD_FAST__LOAD_ATTR_INSTANCE_VALUE_miss: + { + // This is special-cased because we have a superinstruction + // that includes a specialized instruction. + // If the specialized portion misses, carry out + // the first instruction, then perform a miss + // for the second instruction as usual. + + // Do LOAD_FAST + { + PyObject *value = GETLOCAL(oparg); + assert(value != NULL); // Already checked if unbound + Py_INCREF(value); + PUSH(value); + NEXTOPARG(); + next_instr++; + } + + // Now we are in the correct state for LOAD_ATTR + goto LOAD_ATTR_INSTANCE_VALUE_miss; + } + binary_subscr_dict_error: { PyObject *sub = POP(); diff --git a/Python/opcode_targets.h b/Python/opcode_targets.h index cf5bdc772e4..fac671eb024 100644 --- a/Python/opcode_targets.h +++ b/Python/opcode_targets.h @@ -173,7 +173,7 @@ static void *opcode_targets[256] = { &&TARGET_CALL, &&TARGET_KW_NAMES, &&TARGET_STORE_FAST__STORE_FAST, - &&_unknown_opcode, + &&TARGET_LOAD_FAST__LOAD_ATTR_INSTANCE_VALUE, &&_unknown_opcode, &&_unknown_opcode, &&_unknown_opcode, diff --git a/Python/specialize.c b/Python/specialize.c index 816cca1074e..1641766712a 100644 --- a/Python/specialize.c +++ b/Python/specialize.c @@ -889,6 +889,16 @@ _Py_Specialize_LoadAttr(PyObject *owner, _Py_CODEUNIT *instr, PyObject *name, Sp return -1; } if (err) { + if (_Py_OPCODE(instr[0]) == LOAD_ATTR_INSTANCE_VALUE) { + // Note: instr[-1] exists because there's something on the stack, + // and instr[-2] exists because there's at least a RESUME as well. + if (_Py_OPCODE(instr[-1]) == LOAD_FAST) { + instr[-1] = _Py_MAKECODEUNIT(LOAD_FAST__LOAD_ATTR_INSTANCE_VALUE, _Py_OPARG(instr[-1])); + if (_Py_OPCODE(instr[-2]) == LOAD_FAST__LOAD_FAST) { + instr[-2] = _Py_MAKECODEUNIT(LOAD_FAST, _Py_OPARG(instr[-2])); + } + } + } goto success; } fail: