bpo-26280: Port BINARY_SUBSCR to PEP 659 adaptive interpreter (GH-27043)

1 files changed, 47 insertions, 1 deletions

diff --git a/Python/specialize.c b/Python/specialize.c
index 3277c6bc9e..5ebe596418 100644
--- a/Python/specialize.c
+++ b/Python/specialize.c
@@ -78,6 +78,7 @@ _Py_PrintSpecializationStats(void)
     printf("Specialization stats:\n");
     print_stats(&_specialization_stats[LOAD_ATTR], "load_attr");
     print_stats(&_specialization_stats[LOAD_GLOBAL], "load_global");
+    print_stats(&_specialization_stats[BINARY_SUBSCR], "binary_subscr");
 }
 
 #if SPECIALIZATION_STATS_DETAILED
@@ -162,12 +163,14 @@ get_cache_count(SpecializedCacheOrInstruction *quickened) {
 static uint8_t adaptive_opcodes[256] = {
     [LOAD_ATTR] = LOAD_ATTR_ADAPTIVE,
     [LOAD_GLOBAL] = LOAD_GLOBAL_ADAPTIVE,
+    [BINARY_SUBSCR] = BINARY_SUBSCR_ADAPTIVE,
 };
 
 /* The number of cache entries required for a "family" of instructions. */
 static uint8_t cache_requirements[256] = {
     [LOAD_ATTR] = 2, /* _PyAdaptiveEntry and _PyLoadAttrCache */
     [LOAD_GLOBAL] = 2, /* _PyAdaptiveEntry and _PyLoadGlobalCache */
+    [BINARY_SUBSCR] = 0,
 };
 
 /* Return the oparg for the cache_offset and instruction index.
@@ -251,7 +254,6 @@ optimize(SpecializedCacheOrInstruction *quickened, int len)
                 previous_opcode = opcode;
                 continue;
             }
-            instructions[i] = _Py_MAKECODEUNIT(adaptive_opcode, new_oparg);
             previous_opcode = adaptive_opcode;
             int entries_needed = cache_requirements[opcode];
             if (entries_needed) {
@@ -261,7 +263,11 @@ optimize(SpecializedCacheOrInstruction *quickened, int len)
                     _GetSpecializedCacheEntry(instructions, cache0_offset);
                 cache->adaptive.original_oparg = oparg;
                 cache->adaptive.counter = 0;
+            } else {
+                // oparg is the adaptive cache counter
+                new_oparg = 0;
             }
+            instructions[i] = _Py_MAKECODEUNIT(adaptive_opcode, new_oparg);
         }
         else {
             /* Super instructions don't use the cache,
@@ -637,3 +643,43 @@ success:
     cache0->counter = saturating_start();
     return 0;
 }
+
+int
+_Py_Specialize_BinarySubscr(
+     PyObject *container, PyObject *sub, _Py_CODEUNIT *instr)
+{
+    PyTypeObject *container_type = Py_TYPE(container);
+    if (container_type == &PyList_Type) {
+        if (PyLong_CheckExact(sub)) {
+            *instr = _Py_MAKECODEUNIT(BINARY_SUBSCR_LIST_INT, saturating_start());
+            goto success;
+        } else {
+            SPECIALIZATION_FAIL(BINARY_SUBSCR, Py_TYPE(container), sub, "list; non-integer subscr");
+        }
+    }
+    if (container_type == &PyTuple_Type) {
+        if (PyLong_CheckExact(sub)) {
+            *instr = _Py_MAKECODEUNIT(BINARY_SUBSCR_TUPLE_INT, saturating_start());
+            goto success;
+        } else {
+            SPECIALIZATION_FAIL(BINARY_SUBSCR, Py_TYPE(container), sub, "tuple; non-integer subscr");
+        }
+    }
+    if (container_type == &PyDict_Type) {
+        *instr = _Py_MAKECODEUNIT(BINARY_SUBSCR_DICT, saturating_start());
+        goto success;
+    }
+
+    SPECIALIZATION_FAIL(BINARY_SUBSCR, Py_TYPE(container), sub, "not list|tuple|dict");
+    goto fail;
+fail:
+    STAT_INC(BINARY_SUBSCR, specialization_failure);
+    assert(!PyErr_Occurred());
+    *instr = _Py_MAKECODEUNIT(_Py_OPCODE(*instr), ADAPTIVE_CACHE_BACKOFF);
+    return 0;
+success:
+    STAT_INC(BINARY_SUBSCR, specialization_success);
+    assert(!PyErr_Occurred());
+    return 0;
+}
+