/src/cpython/Python/ceval_macros.h
Line | Count | Source |
1 | | // Macros and other things needed by ceval.c, and bytecodes.c |
2 | | |
3 | | /* Computed GOTOs, or |
4 | | the-optimization-commonly-but-improperly-known-as-"threaded code" |
5 | | using gcc's labels-as-values extension |
6 | | (http://gcc.gnu.org/onlinedocs/gcc/Labels-as-Values.html). |
7 | | |
8 | | The traditional bytecode evaluation loop uses a "switch" statement, which |
9 | | decent compilers will optimize as a single indirect branch instruction |
10 | | combined with a lookup table of jump addresses. However, since the |
11 | | indirect jump instruction is shared by all opcodes, the CPU will have a |
12 | | hard time making the right prediction for where to jump next (actually, |
13 | | it will be always wrong except in the uncommon case of a sequence of |
14 | | several identical opcodes). |
15 | | |
16 | | "Threaded code" in contrast, uses an explicit jump table and an explicit |
17 | | indirect jump instruction at the end of each opcode. Since the jump |
18 | | instruction is at a different address for each opcode, the CPU will make a |
19 | | separate prediction for each of these instructions, which is equivalent to |
20 | | predicting the second opcode of each opcode pair. These predictions have |
21 | | a much better chance to turn out valid, especially in small bytecode loops. |
22 | | |
23 | | A mispredicted branch on a modern CPU flushes the whole pipeline and |
24 | | can cost several CPU cycles (depending on the pipeline depth), |
25 | | and potentially many more instructions (depending on the pipeline width). |
26 | | A correctly predicted branch, however, is nearly free. |
27 | | |
28 | | At the time of this writing, the "threaded code" version is up to 15-20% |
29 | | faster than the normal "switch" version, depending on the compiler and the |
30 | | CPU architecture. |
31 | | |
32 | | NOTE: care must be taken that the compiler doesn't try to "optimize" the |
33 | | indirect jumps by sharing them between all opcodes. Such optimizations |
34 | | can be disabled on gcc by using the -fno-gcse flag (or possibly |
35 | | -fno-crossjumping). |
36 | | */ |
37 | | |
38 | | /* Use macros rather than inline functions, to make it as clear as possible |
39 | | * to the C compiler that the tracing check is a simple test then branch. |
40 | | * We want to be sure that the compiler knows this before it generates |
41 | | * the CFG. |
42 | | */ |
43 | | |
44 | | #ifdef WITH_DTRACE |
45 | | #define OR_DTRACE_LINE | (PyDTrace_LINE_ENABLED() ? 255 : 0) |
46 | | #else |
47 | | #define OR_DTRACE_LINE |
48 | | #endif |
49 | | |
50 | | #ifdef HAVE_COMPUTED_GOTOS |
51 | | #ifndef USE_COMPUTED_GOTOS |
52 | | #define USE_COMPUTED_GOTOS 1 |
53 | | #endif |
54 | | #else |
55 | | #if defined(USE_COMPUTED_GOTOS) && USE_COMPUTED_GOTOS |
56 | | #error "Computed gotos are not supported on this compiler." |
57 | | #endif |
58 | | #undef USE_COMPUTED_GOTOS |
59 | | #define USE_COMPUTED_GOTOS 0 |
60 | | #endif |
61 | | |
62 | | #ifdef Py_STATS |
63 | | #define INSTRUCTION_STATS(op) \ |
64 | | do { \ |
65 | | PyStats *s = _PyStats_GET(); \ |
66 | | OPCODE_EXE_INC(op); \ |
67 | | if (s) s->opcode_stats[lastopcode].pair_count[op]++; \ |
68 | | lastopcode = op; \ |
69 | | } while (0) |
70 | | #else |
71 | 37.5G | #define INSTRUCTION_STATS(op) ((void)0) |
72 | | #endif |
73 | | |
74 | | #ifdef Py_STATS |
75 | | # define TAIL_CALL_PARAMS _PyInterpreterFrame *frame, _PyStackRef *stack_pointer, PyThreadState *tstate, _Py_CODEUNIT *next_instr, const void *instruction_funcptr_table, int oparg, int lastopcode |
76 | | # define TAIL_CALL_ARGS frame, stack_pointer, tstate, next_instr, instruction_funcptr_table, oparg, lastopcode |
77 | | #else |
78 | | # define TAIL_CALL_PARAMS _PyInterpreterFrame *frame, _PyStackRef *stack_pointer, PyThreadState *tstate, _Py_CODEUNIT *next_instr, const void *instruction_funcptr_table, int oparg |
79 | | # define TAIL_CALL_ARGS frame, stack_pointer, tstate, next_instr, instruction_funcptr_table, oparg |
80 | | #endif |
81 | | |
82 | | #if _Py_TAIL_CALL_INTERP |
83 | | # if defined(__clang__) || defined(__GNUC__) |
84 | | # if !_Py__has_attribute(preserve_none) || !_Py__has_attribute(musttail) |
85 | | # error "This compiler does not have support for efficient tail calling." |
86 | | # endif |
87 | | # elif defined(_MSC_VER) && (_MSC_VER < 1950) |
88 | | # error "You need at least VS 2026 / PlatformToolset v145 for tail calling." |
89 | | # endif |
90 | | |
91 | | // Note: [[clang::musttail]] works for GCC 15, but not __attribute__((musttail)) at the moment. |
92 | | # define Py_MUSTTAIL [[clang::musttail]] |
93 | | # define Py_PRESERVE_NONE_CC __attribute__((preserve_none)) |
94 | | Py_PRESERVE_NONE_CC typedef PyObject* (*py_tail_call_funcptr)(TAIL_CALL_PARAMS); |
95 | | |
96 | | # define TARGET(op) Py_PRESERVE_NONE_CC PyObject *_TAIL_CALL_##op(TAIL_CALL_PARAMS) |
97 | | # define DISPATCH_GOTO() \ |
98 | | do { \ |
99 | | Py_MUSTTAIL return (((py_tail_call_funcptr *)instruction_funcptr_table)[opcode])(TAIL_CALL_ARGS); \ |
100 | | } while (0) |
101 | | # define JUMP_TO_LABEL(name) \ |
102 | | do { \ |
103 | | Py_MUSTTAIL return (_TAIL_CALL_##name)(TAIL_CALL_ARGS); \ |
104 | | } while (0) |
105 | | # ifdef Py_STATS |
106 | | # define JUMP_TO_PREDICTED(name) \ |
107 | | do { \ |
108 | | Py_MUSTTAIL return (_TAIL_CALL_##name)(frame, stack_pointer, tstate, this_instr, instruction_funcptr_table, oparg, lastopcode); \ |
109 | | } while (0) |
110 | | # else |
111 | | # define JUMP_TO_PREDICTED(name) \ |
112 | | do { \ |
113 | | Py_MUSTTAIL return (_TAIL_CALL_##name)(frame, stack_pointer, tstate, this_instr, instruction_funcptr_table, oparg); \ |
114 | | } while (0) |
115 | | # endif |
116 | | # define LABEL(name) TARGET(name) |
117 | | #elif USE_COMPUTED_GOTOS |
118 | 37.5G | # define TARGET(op) TARGET_##op: |
119 | 37.8G | # define DISPATCH_GOTO() goto *opcode_targets[opcode] |
120 | 48.0M | # define JUMP_TO_LABEL(name) goto name; |
121 | 203M | # define JUMP_TO_PREDICTED(name) goto PREDICTED_##name; |
122 | 318M | # define LABEL(name) name: |
123 | | #else |
124 | | # define TARGET(op) case op: TARGET_##op: |
125 | | # define DISPATCH_GOTO() goto dispatch_opcode |
126 | | # define JUMP_TO_LABEL(name) goto name; |
127 | | # define JUMP_TO_PREDICTED(name) goto PREDICTED_##name; |
128 | | # define LABEL(name) name: |
129 | | #endif |
130 | | |
131 | | /* PRE_DISPATCH_GOTO() does lltrace if enabled. Normally a no-op */ |
132 | | #ifdef Py_DEBUG |
133 | | #define PRE_DISPATCH_GOTO() if (frame->lltrace >= 5) { \ |
134 | | lltrace_instruction(frame, stack_pointer, next_instr, opcode, oparg); } |
135 | | #else |
136 | 37.8G | #define PRE_DISPATCH_GOTO() ((void)0) |
137 | | #endif |
138 | | |
139 | | #ifdef Py_DEBUG |
140 | | #define LLTRACE_RESUME_FRAME() \ |
141 | | do { \ |
142 | | _PyFrame_SetStackPointer(frame, stack_pointer); \ |
143 | | int lltrace = maybe_lltrace_resume_frame(frame, GLOBALS()); \ |
144 | | stack_pointer = _PyFrame_GetStackPointer(frame); \ |
145 | | frame->lltrace = lltrace; \ |
146 | | } while (0) |
147 | | #else |
148 | 1.39G | #define LLTRACE_RESUME_FRAME() ((void)0) |
149 | | #endif |
150 | | |
151 | | #ifdef Py_GIL_DISABLED |
152 | | #define QSBR_QUIESCENT_STATE(tstate) _Py_qsbr_quiescent_state(((_PyThreadStateImpl *)tstate)->qsbr) |
153 | | #else |
154 | | #define QSBR_QUIESCENT_STATE(tstate) |
155 | | #endif |
156 | | |
157 | | |
158 | | /* Do interpreter dispatch accounting for tracing and instrumentation */ |
159 | | #define DISPATCH() \ |
160 | 37.7G | { \ |
161 | 37.7G | assert(frame->stackpointer == NULL); \ |
162 | 37.7G | NEXTOPARG(); \ |
163 | 37.7G | PRE_DISPATCH_GOTO(); \ |
164 | 37.7G | DISPATCH_GOTO(); \ |
165 | 37.7G | } |
166 | | |
167 | | #define DISPATCH_SAME_OPARG() \ |
168 | 4.29M | { \ |
169 | 4.29M | opcode = next_instr->op.code; \ |
170 | 4.29M | PRE_DISPATCH_GOTO(); \ |
171 | 4.29M | DISPATCH_GOTO(); \ |
172 | 4.29M | } |
173 | | |
174 | | #define DISPATCH_INLINED(NEW_FRAME) \ |
175 | 1.04M | do { \ |
176 | 1.04M | assert(tstate->interp->eval_frame == NULL); \ |
177 | 1.04M | _PyFrame_SetStackPointer(frame, stack_pointer); \ |
178 | 1.04M | assert((NEW_FRAME)->previous == frame); \ |
179 | 1.04M | frame = tstate->current_frame = (NEW_FRAME); \ |
180 | 1.04M | CALL_STAT_INC(inlined_py_calls); \ |
181 | 1.04M | JUMP_TO_LABEL(start_frame); \ |
182 | 0 | } while (0) |
183 | | |
184 | | /* Tuple access macros */ |
185 | | |
186 | | #ifndef Py_DEBUG |
187 | 1.63G | #define GETITEM(v, i) PyTuple_GET_ITEM((v), (i)) |
188 | | #else |
189 | | static inline PyObject * |
190 | | GETITEM(PyObject *v, Py_ssize_t i) { |
191 | | assert(PyTuple_Check(v)); |
192 | | assert(i >= 0); |
193 | | assert(i < PyTuple_GET_SIZE(v)); |
194 | | return PyTuple_GET_ITEM(v, i); |
195 | | } |
196 | | #endif |
197 | | |
198 | | /* Code access macros */ |
199 | | |
200 | | /* The integer overflow is checked by an assertion below. */ |
201 | 32.3M | #define INSTR_OFFSET() ((int)(next_instr - _PyFrame_GetBytecode(frame))) |
202 | 37.7G | #define NEXTOPARG() do { \ |
203 | 37.7G | _Py_CODEUNIT word = {.cache = FT_ATOMIC_LOAD_UINT16_RELAXED(*(uint16_t*)next_instr)}; \ |
204 | 37.7G | opcode = word.op.code; \ |
205 | 37.7G | oparg = word.op.arg; \ |
206 | 37.7G | } while (0) |
207 | | |
208 | | /* JUMPBY makes the generator identify the instruction as a jump. SKIP_OVER is |
209 | | * for advancing to the next instruction, taking into account cache entries |
210 | | * and skipped instructions. |
211 | | */ |
212 | 5.19G | #define JUMPBY(x) (next_instr += (x)) |
213 | 308M | #define SKIP_OVER(x) (next_instr += (x)) |
214 | | |
215 | | #define STACK_LEVEL() ((int)(stack_pointer - _PyFrame_Stackbase(frame))) |
216 | | #define STACK_SIZE() (_PyFrame_GetCode(frame)->co_stacksize) |
217 | | |
218 | | #define WITHIN_STACK_BOUNDS() \ |
219 | | (frame->owner == FRAME_OWNED_BY_INTERPRETER || (STACK_LEVEL() >= 0 && STACK_LEVEL() <= STACK_SIZE())) |
220 | | |
221 | | /* Data access macros */ |
222 | | #define FRAME_CO_CONSTS (_PyFrame_GetCode(frame)->co_consts) |
223 | | #define FRAME_CO_NAMES (_PyFrame_GetCode(frame)->co_names) |
224 | | |
225 | | /* Local variable macros */ |
226 | | |
227 | 1.04M | #define LOCALS_ARRAY (frame->localsplus) |
228 | 18.1G | #define GETLOCAL(i) (frame->localsplus[i]) |
229 | | |
230 | | |
231 | | #ifdef Py_STATS |
232 | | #define UPDATE_MISS_STATS(INSTNAME) \ |
233 | | do { \ |
234 | | STAT_INC(opcode, miss); \ |
235 | | STAT_INC((INSTNAME), miss); \ |
236 | | /* The counter is always the first cache entry: */ \ |
237 | | if (ADAPTIVE_COUNTER_TRIGGERS(next_instr->cache)) { \ |
238 | | STAT_INC((INSTNAME), deopt); \ |
239 | | } \ |
240 | | } while (0) |
241 | | #else |
242 | 203M | #define UPDATE_MISS_STATS(INSTNAME) ((void)0) |
243 | | #endif |
244 | | |
245 | | |
246 | | // Try to lock an object in the free threading build, if it's not already |
247 | | // locked. Use with a DEOPT_IF() to deopt if the object is already locked. |
248 | | // These are no-ops in the default GIL build. The general pattern is: |
249 | | // |
250 | | // DEOPT_IF(!LOCK_OBJECT(op)); |
251 | | // if (/* condition fails */) { |
252 | | // UNLOCK_OBJECT(op); |
253 | | // DEOPT_IF(true); |
254 | | // } |
255 | | // ... |
256 | | // UNLOCK_OBJECT(op); |
257 | | // |
258 | | // NOTE: The object must be unlocked on every exit code path and you should |
259 | | // avoid any potentially escaping calls (like PyStackRef_CLOSE) while the |
260 | | // object is locked. |
261 | | #ifdef Py_GIL_DISABLED |
262 | | # define LOCK_OBJECT(op) PyMutex_LockFast(&(_PyObject_CAST(op))->ob_mutex) |
263 | | # define UNLOCK_OBJECT(op) PyMutex_Unlock(&(_PyObject_CAST(op))->ob_mutex) |
264 | | #else |
265 | 471M | # define LOCK_OBJECT(op) (1) |
266 | 471M | # define UNLOCK_OBJECT(op) ((void)0) |
267 | | #endif |
268 | | |
269 | 698M | #define GLOBALS() frame->f_globals |
270 | 392M | #define BUILTINS() frame->f_builtins |
271 | 98.5k | #define LOCALS() frame->f_locals |
272 | | #define CONSTS() _PyFrame_GetCode(frame)->co_consts |
273 | | #define NAMES() _PyFrame_GetCode(frame)->co_names |
274 | | |
275 | | #define DTRACE_FUNCTION_ENTRY() \ |
276 | | if (PyDTrace_FUNCTION_ENTRY_ENABLED()) { \ |
277 | | dtrace_function_entry(frame); \ |
278 | | } |
279 | | |
280 | | /* This takes a uint16_t instead of a _Py_BackoffCounter, |
281 | | * because it is used directly on the cache entry in generated code, |
282 | | * which is always an integral type. */ |
283 | | #define ADAPTIVE_COUNTER_TRIGGERS(COUNTER) \ |
284 | 1.18G | backoff_counter_triggers(forge_backoff_counter((COUNTER))) |
285 | | |
286 | | #define ADVANCE_ADAPTIVE_COUNTER(COUNTER) \ |
287 | 1.18G | do { \ |
288 | 1.18G | (COUNTER) = advance_backoff_counter((COUNTER)); \ |
289 | 1.18G | } while (0); |
290 | | |
291 | | #define PAUSE_ADAPTIVE_COUNTER(COUNTER) \ |
292 | 0 | do { \ |
293 | 0 | (COUNTER) = pause_backoff_counter((COUNTER)); \ |
294 | 0 | } while (0); |
295 | | |
296 | | #ifdef ENABLE_SPECIALIZATION_FT |
297 | | /* Multiple threads may execute these concurrently if thread-local bytecode is |
298 | | * disabled and they all execute the main copy of the bytecode. Specialization |
299 | | * is disabled in that case so the value is unused, but the RMW cycle should be |
300 | | * free of data races. |
301 | | */ |
302 | | #define RECORD_BRANCH_TAKEN(bitset, flag) \ |
303 | 2.59G | FT_ATOMIC_STORE_UINT16_RELAXED( \ |
304 | 2.59G | bitset, (FT_ATOMIC_LOAD_UINT16_RELAXED(bitset) << 1) | (flag)) |
305 | | #else |
306 | | #define RECORD_BRANCH_TAKEN(bitset, flag) |
307 | | #endif |
308 | | |
309 | | #define UNBOUNDLOCAL_ERROR_MSG \ |
310 | 0 | "cannot access local variable '%s' where it is not associated with a value" |
311 | | #define UNBOUNDFREE_ERROR_MSG \ |
312 | 0 | "cannot access free variable '%s' where it is not associated with a value" \ |
313 | 0 | " in enclosing scope" |
314 | 17 | #define NAME_ERROR_MSG "name '%.200s' is not defined" |
315 | | |
316 | | // If a trace function sets a new f_lineno and |
317 | | // *then* raises, we use the destination when searching |
318 | | // for an exception handler, displaying the traceback, and so on |
319 | 0 | #define INSTRUMENTED_JUMP(src, dest, event) \ |
320 | 0 | do { \ |
321 | 0 | if (tstate->tracing) {\ |
322 | 0 | next_instr = dest; \ |
323 | 0 | } else { \ |
324 | 0 | _PyFrame_SetStackPointer(frame, stack_pointer); \ |
325 | 0 | next_instr = _Py_call_instrumentation_jump(this_instr, tstate, event, frame, src, dest); \ |
326 | 0 | stack_pointer = _PyFrame_GetStackPointer(frame); \ |
327 | 0 | if (next_instr == NULL) { \ |
328 | 0 | next_instr = (dest)+1; \ |
329 | 0 | JUMP_TO_LABEL(error); \ |
330 | 0 | } \ |
331 | 0 | } \ |
332 | 0 | } while (0); |
333 | | |
334 | | |
335 | 238M | static inline int _Py_EnterRecursivePy(PyThreadState *tstate) { |
336 | 238M | return (tstate->py_recursion_remaining-- <= 0) && |
337 | 161 | _Py_CheckRecursiveCallPy(tstate); |
338 | 238M | } |
339 | | |
340 | 712M | static inline void _Py_LeaveRecursiveCallPy(PyThreadState *tstate) { |
341 | 712M | tstate->py_recursion_remaining++; |
342 | 712M | } |
343 | | |
344 | | /* Implementation of "macros" that modify the instruction pointer, |
345 | | * stack pointer, or frame pointer. |
346 | | * These need to treated differently by tier 1 and 2. |
347 | | * The Tier 1 version is here; Tier 2 is inlined in ceval.c. */ |
348 | | |
349 | 1.17G | #define LOAD_IP(OFFSET) do { \ |
350 | 1.17G | next_instr = frame->instr_ptr + (OFFSET); \ |
351 | 1.17G | } while (0) |
352 | | |
353 | | /* There's no STORE_IP(), it's inlined by the code generator. */ |
354 | | |
355 | 473M | #define LOAD_SP() \ |
356 | 473M | stack_pointer = _PyFrame_GetStackPointer(frame) |
357 | | |
358 | | #define SAVE_SP() \ |
359 | | _PyFrame_SetStackPointer(frame, stack_pointer) |
360 | | |
361 | | /* Tier-switching macros. */ |
362 | | |
363 | | #define TIER1_TO_TIER2(EXECUTOR) \ |
364 | | do { \ |
365 | | OPT_STAT_INC(traces_executed); \ |
366 | | next_instr = _Py_jit_entry((EXECUTOR), frame, stack_pointer, tstate); \ |
367 | | frame = tstate->current_frame; \ |
368 | | stack_pointer = _PyFrame_GetStackPointer(frame); \ |
369 | | if (next_instr == NULL) { \ |
370 | | /* gh-140104: The exception handler expects frame->instr_ptr |
371 | | to after this_instr, not this_instr! */ \ |
372 | | next_instr = frame->instr_ptr + 1; \ |
373 | | JUMP_TO_LABEL(error); \ |
374 | | } \ |
375 | | DISPATCH(); \ |
376 | | } while (0) |
377 | | |
378 | | #define TIER2_TO_TIER2(EXECUTOR) \ |
379 | | do { \ |
380 | | OPT_STAT_INC(traces_executed); \ |
381 | | current_executor = (EXECUTOR); \ |
382 | | goto tier2_start; \ |
383 | | } while (0) |
384 | | |
385 | | #define GOTO_TIER_ONE(TARGET) \ |
386 | | do \ |
387 | | { \ |
388 | | tstate->current_executor = NULL; \ |
389 | | OPT_HIST(trace_uop_execution_counter, trace_run_length_hist); \ |
390 | | _PyFrame_SetStackPointer(frame, stack_pointer); \ |
391 | | return TARGET; \ |
392 | | } while (0) |
393 | | |
394 | | #define CURRENT_OPARG() (next_uop[-1].oparg) |
395 | | #define CURRENT_OPERAND0() (next_uop[-1].operand0) |
396 | | #define CURRENT_OPERAND1() (next_uop[-1].operand1) |
397 | | #define CURRENT_TARGET() (next_uop[-1].target) |
398 | | |
399 | | #define JUMP_TO_JUMP_TARGET() goto jump_to_jump_target |
400 | | #define JUMP_TO_ERROR() goto jump_to_error_target |
401 | | |
402 | | /* Stackref macros */ |
403 | | |
404 | | /* How much scratch space to give stackref to PyObject* conversion. */ |
405 | 1.78G | #define MAX_STACKREF_SCRATCH 10 |
406 | | |
407 | | #define STACKREFS_TO_PYOBJECTS(ARGS, ARG_COUNT, NAME) \ |
408 | | /* +1 because vectorcall might use -1 to write self */ \ |
409 | 1.78G | PyObject *NAME##_temp[MAX_STACKREF_SCRATCH+1]; \ |
410 | 1.78G | PyObject **NAME = _PyObjectArray_FromStackRefArray(ARGS, ARG_COUNT, NAME##_temp + 1); |
411 | | |
412 | | #define STACKREFS_TO_PYOBJECTS_CLEANUP(NAME) \ |
413 | | /* +1 because we +1 previously */ \ |
414 | 1.78G | _PyObjectArray_Free(NAME - 1, NAME##_temp); |
415 | | |
416 | 1.78G | #define CONVERSION_FAILED(NAME) ((NAME) == NULL) |
417 | | |
418 | | static inline int |
419 | 3.07G | check_periodics(PyThreadState *tstate) { |
420 | 3.07G | _Py_CHECK_EMSCRIPTEN_SIGNALS_PERIODICALLY(); |
421 | 3.07G | QSBR_QUIESCENT_STATE(tstate); |
422 | 3.07G | if (_Py_atomic_load_uintptr_relaxed(&tstate->eval_breaker) & _PY_EVAL_EVENTS_MASK) { |
423 | 31.3k | return _Py_HandlePending(tstate); |
424 | 31.3k | } |
425 | 3.07G | return 0; |
426 | 3.07G | } |
427 | | |