mirrors/cpython
1
0
Fork 0
mirror of https://github.com/python/cpython.git synced 2025-07-24 11:44:31 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions 8

bpo-44337: Port LOAD_ATTR to PEP 659 adaptive interpreter (GH-26595)

Browse source 
* Specialize LOAD_ATTR with  LOAD_ATTR_SLOT and LOAD_ATTR_SPLIT_KEYS

* Move dict-common.h to internal/pycore_dict.h

* Add LOAD_ATTR_WITH_HINT specialized opcode.

* Quicken in function if loopy

* Specialize LOAD_ATTR for module attributes.

* Add specialization stats
This commit is contained in:
Mark Shannon 2021-06-10 08:46:01 +01:00 • committed by GitHub
parent 309ab61602
commit e117c02837
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
14 changed files with 511 additions and 221 deletions
Download patch file Download diff file Expand all files Collapse all files

84
Include/internal/pycore_code.h
View file

@ -42,6 +42,12 @@ typedef struct {
uint16_t index;
} _PyAdaptiveEntry;
typedef struct {
uint32_t tp_version;
uint32_t dk_version_or_hint;
} _PyLoadAttrCache;
/* Add specialized versions of entries to this union.
*
* Do not break the invariant: sizeof(SpecializedCacheEntry) == 8
@ -55,6 +61,7 @@ typedef struct {
typedef union {
_PyEntryZero zero;
_PyAdaptiveEntry adaptive;
_PyLoadAttrCache load_attr;
} SpecializedCacheEntry;
#define INSTRUCTIONS_PER_ENTRY (sizeof(SpecializedCacheEntry)/sizeof(_Py_CODEUNIT))
@ -255,6 +262,83 @@ PyAPI_FUNC(PyObject *) _PyCode_GetCellvars(PyCodeObject *);
PyAPI_FUNC(PyObject *) _PyCode_GetFreevars(PyCodeObject *);
/* Cache hits and misses */
static inline uint8_t
saturating_increment(uint8_t c)
{
return c<<1;
}
static inline uint8_t
saturating_decrement(uint8_t c)
{
return (c>>1) + 128;
}
static inline uint8_t
saturating_zero(void)
{
return 255;
}
/* Starting value for saturating counter.
* Technically this should be 1, but that is likely to
* cause a bit of thrashing when we optimize then get an immediate miss.
* We want to give the counter a change to stabilize, so we start at 3.
*/
static inline uint8_t
saturating_start(void)
{
return saturating_zero()<<3;
}
static inline void
record_cache_hit(_PyAdaptiveEntry *entry) {
entry->counter = saturating_increment(entry->counter);
}
static inline void
record_cache_miss(_PyAdaptiveEntry *entry) {
entry->counter = saturating_decrement(entry->counter);
}
static inline int
too_many_cache_misses(_PyAdaptiveEntry *entry) {
return entry->counter == saturating_zero();
}
#define BACKOFF 64
static inline void
cache_backoff(_PyAdaptiveEntry *entry) {
entry->counter = BACKOFF;
}
/* Specialization functions */
int _Py_Specialize_LoadAttr(PyObject *owner, _Py_CODEUNIT *instr, PyObject *name, SpecializedCacheEntry *cache);
#define SPECIALIZATION_STATS 0
#if SPECIALIZATION_STATS
typedef struct _specialization_stats {
uint64_t specialization_success;
uint64_t specialization_failure;
uint64_t loadattr_hit;
uint64_t loadattr_deferred;
uint64_t loadattr_miss;
uint64_t loadattr_deopt;
} SpecializationStats;
extern SpecializationStats _specialization_stats;
#define STAT_INC(name) _specialization_stats.name++
void _Py_PrintSpecializationStats(void);
#else
#define STAT_INC(name) ((void)0)
#endif
#ifdef __cplusplus
}
#endif