/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 | | OPCODE_EXE_INC(op); \ |
66 | | if (_Py_stats) _Py_stats->opcode_stats[lastopcode].pair_count[op]++; \ |
67 | | lastopcode = op; \ |
68 | | } while (0) |
69 | | #else |
70 | 42.7G | #define INSTRUCTION_STATS(op) ((void)0) |
71 | | #endif |
72 | | |
73 | | #ifdef Py_STATS |
74 | | # define TAIL_CALL_PARAMS _PyInterpreterFrame *frame, _PyStackRef *stack_pointer, PyThreadState *tstate, _Py_CODEUNIT *next_instr, const void *instruction_funcptr_table, int oparg, int lastopcode |
75 | | # define TAIL_CALL_ARGS frame, stack_pointer, tstate, next_instr, instruction_funcptr_table, oparg, lastopcode |
76 | | #else |
77 | | # define TAIL_CALL_PARAMS _PyInterpreterFrame *frame, _PyStackRef *stack_pointer, PyThreadState *tstate, _Py_CODEUNIT *next_instr, const void *instruction_funcptr_table, int oparg |
78 | | # define TAIL_CALL_ARGS frame, stack_pointer, tstate, next_instr, instruction_funcptr_table, oparg |
79 | | #endif |
80 | | |
81 | | #if _Py_TAIL_CALL_INTERP |
82 | | # if defined(__clang__) || defined(__GNUC__) |
83 | | # if !_Py__has_attribute(preserve_none) || !_Py__has_attribute(musttail) |
84 | | # error "This compiler does not have support for efficient tail calling." |
85 | | # endif |
86 | | # elif defined(_MSC_VER) && (_MSC_VER < 1950) |
87 | | # error "You need at least VS 2026 / PlatformToolset v145 for tail calling." |
88 | | # endif |
89 | | |
90 | | // Note: [[clang::musttail]] works for GCC 15, but not __attribute__((musttail)) at the moment. |
91 | | # define Py_MUSTTAIL [[clang::musttail]] |
92 | | # define Py_PRESERVE_NONE_CC __attribute__((preserve_none)) |
93 | | Py_PRESERVE_NONE_CC typedef PyObject* (*py_tail_call_funcptr)(TAIL_CALL_PARAMS); |
94 | | |
95 | | # define TARGET(op) Py_PRESERVE_NONE_CC PyObject *_TAIL_CALL_##op(TAIL_CALL_PARAMS) |
96 | | # define DISPATCH_GOTO() \ |
97 | | do { \ |
98 | | Py_MUSTTAIL return (((py_tail_call_funcptr *)instruction_funcptr_table)[opcode])(TAIL_CALL_ARGS); \ |
99 | | } while (0) |
100 | | # define JUMP_TO_LABEL(name) \ |
101 | | do { \ |
102 | | Py_MUSTTAIL return (_TAIL_CALL_##name)(TAIL_CALL_ARGS); \ |
103 | | } while (0) |
104 | | # ifdef Py_STATS |
105 | | # define JUMP_TO_PREDICTED(name) \ |
106 | | do { \ |
107 | | Py_MUSTTAIL return (_TAIL_CALL_##name)(frame, stack_pointer, tstate, this_instr, instruction_funcptr_table, oparg, lastopcode); \ |
108 | | } while (0) |
109 | | # else |
110 | | # define JUMP_TO_PREDICTED(name) \ |
111 | | do { \ |
112 | | Py_MUSTTAIL return (_TAIL_CALL_##name)(frame, stack_pointer, tstate, this_instr, instruction_funcptr_table, oparg); \ |
113 | | } while (0) |
114 | | # endif |
115 | | # define LABEL(name) TARGET(name) |
116 | | #elif USE_COMPUTED_GOTOS |
117 | 42.7G | # define TARGET(op) TARGET_##op: |
118 | 43.1G | # define DISPATCH_GOTO() goto *opcode_targets[opcode] |
119 | 44.9M | # define JUMP_TO_LABEL(name) goto name; |
120 | 187M | # define JUMP_TO_PREDICTED(name) goto PREDICTED_##name; |
121 | 305M | # define LABEL(name) name: |
122 | | #else |
123 | | # define TARGET(op) case op: TARGET_##op: |
124 | | # define DISPATCH_GOTO() goto dispatch_opcode |
125 | | # define JUMP_TO_LABEL(name) goto name; |
126 | | # define JUMP_TO_PREDICTED(name) goto PREDICTED_##name; |
127 | | # define LABEL(name) name: |
128 | | #endif |
129 | | |
130 | | /* PRE_DISPATCH_GOTO() does lltrace if enabled. Normally a no-op */ |
131 | | #ifdef Py_DEBUG |
132 | | #define PRE_DISPATCH_GOTO() if (frame->lltrace >= 5) { \ |
133 | | lltrace_instruction(frame, stack_pointer, next_instr, opcode, oparg); } |
134 | | #else |
135 | 43.1G | #define PRE_DISPATCH_GOTO() ((void)0) |
136 | | #endif |
137 | | |
138 | | #ifdef Py_DEBUG |
139 | | #define LLTRACE_RESUME_FRAME() \ |
140 | | do { \ |
141 | | _PyFrame_SetStackPointer(frame, stack_pointer); \ |
142 | | int lltrace = maybe_lltrace_resume_frame(frame, GLOBALS()); \ |
143 | | stack_pointer = _PyFrame_GetStackPointer(frame); \ |
144 | | frame->lltrace = lltrace; \ |
145 | | } while (0) |
146 | | #else |
147 | 1.32G | #define LLTRACE_RESUME_FRAME() ((void)0) |
148 | | #endif |
149 | | |
150 | | #ifdef Py_GIL_DISABLED |
151 | | #define QSBR_QUIESCENT_STATE(tstate) _Py_qsbr_quiescent_state(((_PyThreadStateImpl *)tstate)->qsbr) |
152 | | #else |
153 | | #define QSBR_QUIESCENT_STATE(tstate) |
154 | | #endif |
155 | | |
156 | | |
157 | | /* Do interpreter dispatch accounting for tracing and instrumentation */ |
158 | | #define DISPATCH() \ |
159 | 43.0G | { \ |
160 | 43.0G | assert(frame->stackpointer == NULL); \ |
161 | 43.0G | NEXTOPARG(); \ |
162 | 43.0G | PRE_DISPATCH_GOTO(); \ |
163 | 43.0G | DISPATCH_GOTO(); \ |
164 | 43.0G | } |
165 | | |
166 | | #define DISPATCH_SAME_OPARG() \ |
167 | 3.95M | { \ |
168 | 3.95M | opcode = next_instr->op.code; \ |
169 | 3.95M | PRE_DISPATCH_GOTO(); \ |
170 | 3.95M | DISPATCH_GOTO(); \ |
171 | 3.95M | } |
172 | | |
173 | | #define DISPATCH_INLINED(NEW_FRAME) \ |
174 | 949k | do { \ |
175 | 949k | assert(tstate->interp->eval_frame == NULL); \ |
176 | 949k | _PyFrame_SetStackPointer(frame, stack_pointer); \ |
177 | 949k | assert((NEW_FRAME)->previous == frame); \ |
178 | 949k | frame = tstate->current_frame = (NEW_FRAME); \ |
179 | 949k | CALL_STAT_INC(inlined_py_calls); \ |
180 | 949k | JUMP_TO_LABEL(start_frame); \ |
181 | 0 | } while (0) |
182 | | |
183 | | /* Tuple access macros */ |
184 | | |
185 | | #ifndef Py_DEBUG |
186 | 1.69G | #define GETITEM(v, i) PyTuple_GET_ITEM((v), (i)) |
187 | | #else |
188 | | static inline PyObject * |
189 | | GETITEM(PyObject *v, Py_ssize_t i) { |
190 | | assert(PyTuple_Check(v)); |
191 | | assert(i >= 0); |
192 | | assert(i < PyTuple_GET_SIZE(v)); |
193 | | return PyTuple_GET_ITEM(v, i); |
194 | | } |
195 | | #endif |
196 | | |
197 | | /* Code access macros */ |
198 | | |
199 | | /* The integer overflow is checked by an assertion below. */ |
200 | 31.6M | #define INSTR_OFFSET() ((int)(next_instr - _PyFrame_GetBytecode(frame))) |
201 | 43.0G | #define NEXTOPARG() do { \ |
202 | 43.0G | _Py_CODEUNIT word = {.cache = FT_ATOMIC_LOAD_UINT16_RELAXED(*(uint16_t*)next_instr)}; \ |
203 | 43.0G | opcode = word.op.code; \ |
204 | 43.0G | oparg = word.op.arg; \ |
205 | 43.0G | } while (0) |
206 | | |
207 | | /* JUMPBY makes the generator identify the instruction as a jump. SKIP_OVER is |
208 | | * for advancing to the next instruction, taking into account cache entries |
209 | | * and skipped instructions. |
210 | | */ |
211 | 6.26G | #define JUMPBY(x) (next_instr += (x)) |
212 | 294M | #define SKIP_OVER(x) (next_instr += (x)) |
213 | | |
214 | | #define STACK_LEVEL() ((int)(stack_pointer - _PyFrame_Stackbase(frame))) |
215 | | #define STACK_SIZE() (_PyFrame_GetCode(frame)->co_stacksize) |
216 | | |
217 | | #define WITHIN_STACK_BOUNDS() \ |
218 | | (frame->owner == FRAME_OWNED_BY_INTERPRETER || (STACK_LEVEL() >= 0 && STACK_LEVEL() <= STACK_SIZE())) |
219 | | |
220 | | /* Data access macros */ |
221 | | #define FRAME_CO_CONSTS (_PyFrame_GetCode(frame)->co_consts) |
222 | | #define FRAME_CO_NAMES (_PyFrame_GetCode(frame)->co_names) |
223 | | |
224 | | /* Local variable macros */ |
225 | | |
226 | 970k | #define LOCALS_ARRAY (frame->localsplus) |
227 | 20.8G | #define GETLOCAL(i) (frame->localsplus[i]) |
228 | | |
229 | | |
230 | | #ifdef Py_STATS |
231 | | #define UPDATE_MISS_STATS(INSTNAME) \ |
232 | | do { \ |
233 | | STAT_INC(opcode, miss); \ |
234 | | STAT_INC((INSTNAME), miss); \ |
235 | | /* The counter is always the first cache entry: */ \ |
236 | | if (ADAPTIVE_COUNTER_TRIGGERS(next_instr->cache)) { \ |
237 | | STAT_INC((INSTNAME), deopt); \ |
238 | | } \ |
239 | | } while (0) |
240 | | #else |
241 | 187M | #define UPDATE_MISS_STATS(INSTNAME) ((void)0) |
242 | | #endif |
243 | | |
244 | | |
245 | | // Try to lock an object in the free threading build, if it's not already |
246 | | // locked. Use with a DEOPT_IF() to deopt if the object is already locked. |
247 | | // These are no-ops in the default GIL build. The general pattern is: |
248 | | // |
249 | | // DEOPT_IF(!LOCK_OBJECT(op)); |
250 | | // if (/* condition fails */) { |
251 | | // UNLOCK_OBJECT(op); |
252 | | // DEOPT_IF(true); |
253 | | // } |
254 | | // ... |
255 | | // UNLOCK_OBJECT(op); |
256 | | // |
257 | | // NOTE: The object must be unlocked on every exit code path and you should |
258 | | // avoid any potentially escaping calls (like PyStackRef_CLOSE) while the |
259 | | // object is locked. |
260 | | #ifdef Py_GIL_DISABLED |
261 | | # define LOCK_OBJECT(op) PyMutex_LockFast(&(_PyObject_CAST(op))->ob_mutex) |
262 | | # define UNLOCK_OBJECT(op) PyMutex_Unlock(&(_PyObject_CAST(op))->ob_mutex) |
263 | | #else |
264 | 440M | # define LOCK_OBJECT(op) (1) |
265 | 440M | # define UNLOCK_OBJECT(op) ((void)0) |
266 | | #endif |
267 | | |
268 | 667M | #define GLOBALS() frame->f_globals |
269 | 387M | #define BUILTINS() frame->f_builtins |
270 | 77.9k | #define LOCALS() frame->f_locals |
271 | | #define CONSTS() _PyFrame_GetCode(frame)->co_consts |
272 | | #define NAMES() _PyFrame_GetCode(frame)->co_names |
273 | | |
274 | | #define DTRACE_FUNCTION_ENTRY() \ |
275 | | if (PyDTrace_FUNCTION_ENTRY_ENABLED()) { \ |
276 | | dtrace_function_entry(frame); \ |
277 | | } |
278 | | |
279 | | /* This takes a uint16_t instead of a _Py_BackoffCounter, |
280 | | * because it is used directly on the cache entry in generated code, |
281 | | * which is always an integral type. */ |
282 | | #define ADAPTIVE_COUNTER_TRIGGERS(COUNTER) \ |
283 | 1.12G | backoff_counter_triggers(forge_backoff_counter((COUNTER))) |
284 | | |
285 | | #define ADVANCE_ADAPTIVE_COUNTER(COUNTER) \ |
286 | 1.12G | do { \ |
287 | 1.12G | (COUNTER) = advance_backoff_counter((COUNTER)); \ |
288 | 1.12G | } while (0); |
289 | | |
290 | | #define PAUSE_ADAPTIVE_COUNTER(COUNTER) \ |
291 | 0 | do { \ |
292 | 0 | (COUNTER) = pause_backoff_counter((COUNTER)); \ |
293 | 0 | } while (0); |
294 | | |
295 | | #ifdef ENABLE_SPECIALIZATION_FT |
296 | | /* Multiple threads may execute these concurrently if thread-local bytecode is |
297 | | * disabled and they all execute the main copy of the bytecode. Specialization |
298 | | * is disabled in that case so the value is unused, but the RMW cycle should be |
299 | | * free of data races. |
300 | | */ |
301 | | #define RECORD_BRANCH_TAKEN(bitset, flag) \ |
302 | 3.13G | FT_ATOMIC_STORE_UINT16_RELAXED( \ |
303 | 3.13G | bitset, (FT_ATOMIC_LOAD_UINT16_RELAXED(bitset) << 1) | (flag)) |
304 | | #else |
305 | | #define RECORD_BRANCH_TAKEN(bitset, flag) |
306 | | #endif |
307 | | |
308 | | #define UNBOUNDLOCAL_ERROR_MSG \ |
309 | 0 | "cannot access local variable '%s' where it is not associated with a value" |
310 | | #define UNBOUNDFREE_ERROR_MSG \ |
311 | 0 | "cannot access free variable '%s' where it is not associated with a value" \ |
312 | 0 | " in enclosing scope" |
313 | 1 | #define NAME_ERROR_MSG "name '%.200s' is not defined" |
314 | | |
315 | | // If a trace function sets a new f_lineno and |
316 | | // *then* raises, we use the destination when searching |
317 | | // for an exception handler, displaying the traceback, and so on |
318 | 0 | #define INSTRUMENTED_JUMP(src, dest, event) \ |
319 | 0 | do { \ |
320 | 0 | if (tstate->tracing) {\ |
321 | 0 | next_instr = dest; \ |
322 | 0 | } else { \ |
323 | 0 | _PyFrame_SetStackPointer(frame, stack_pointer); \ |
324 | 0 | next_instr = _Py_call_instrumentation_jump(this_instr, tstate, event, frame, src, dest); \ |
325 | 0 | stack_pointer = _PyFrame_GetStackPointer(frame); \ |
326 | 0 | if (next_instr == NULL) { \ |
327 | 0 | next_instr = (dest)+1; \ |
328 | 0 | JUMP_TO_LABEL(error); \ |
329 | 0 | } \ |
330 | 0 | } \ |
331 | 0 | } while (0); |
332 | | |
333 | | |
334 | 229M | static inline int _Py_EnterRecursivePy(PyThreadState *tstate) { |
335 | 229M | return (tstate->py_recursion_remaining-- <= 0) && |
336 | 162 | _Py_CheckRecursiveCallPy(tstate); |
337 | 229M | } |
338 | | |
339 | 674M | static inline void _Py_LeaveRecursiveCallPy(PyThreadState *tstate) { |
340 | 674M | tstate->py_recursion_remaining++; |
341 | 674M | } |
342 | | |
343 | | /* Implementation of "macros" that modify the instruction pointer, |
344 | | * stack pointer, or frame pointer. |
345 | | * These need to treated differently by tier 1 and 2. |
346 | | * The Tier 1 version is here; Tier 2 is inlined in ceval.c. */ |
347 | | |
348 | 1.10G | #define LOAD_IP(OFFSET) do { \ |
349 | 1.10G | next_instr = frame->instr_ptr + (OFFSET); \ |
350 | 1.10G | } while (0) |
351 | | |
352 | | /* There's no STORE_IP(), it's inlined by the code generator. */ |
353 | | |
354 | 444M | #define LOAD_SP() \ |
355 | 444M | stack_pointer = _PyFrame_GetStackPointer(frame) |
356 | | |
357 | | #define SAVE_SP() \ |
358 | | _PyFrame_SetStackPointer(frame, stack_pointer) |
359 | | |
360 | | /* Tier-switching macros. */ |
361 | | |
362 | | #define TIER1_TO_TIER2(EXECUTOR) \ |
363 | | do { \ |
364 | | OPT_STAT_INC(traces_executed); \ |
365 | | next_instr = _Py_jit_entry((EXECUTOR), frame, stack_pointer, tstate); \ |
366 | | frame = tstate->current_frame; \ |
367 | | stack_pointer = _PyFrame_GetStackPointer(frame); \ |
368 | | if (next_instr == NULL) { \ |
369 | | /* gh-140104: The exception handler expects frame->instr_ptr |
370 | | to after this_instr, not this_instr! */ \ |
371 | | next_instr = frame->instr_ptr + 1; \ |
372 | | JUMP_TO_LABEL(error); \ |
373 | | } \ |
374 | | DISPATCH(); \ |
375 | | } while (0) |
376 | | |
377 | | #define TIER2_TO_TIER2(EXECUTOR) \ |
378 | | do { \ |
379 | | OPT_STAT_INC(traces_executed); \ |
380 | | current_executor = (EXECUTOR); \ |
381 | | goto tier2_start; \ |
382 | | } while (0) |
383 | | |
384 | | #define GOTO_TIER_ONE(TARGET) \ |
385 | | do \ |
386 | | { \ |
387 | | tstate->current_executor = NULL; \ |
388 | | OPT_HIST(trace_uop_execution_counter, trace_run_length_hist); \ |
389 | | _PyFrame_SetStackPointer(frame, stack_pointer); \ |
390 | | return TARGET; \ |
391 | | } while (0) |
392 | | |
393 | | #define CURRENT_OPARG() (next_uop[-1].oparg) |
394 | | #define CURRENT_OPERAND0() (next_uop[-1].operand0) |
395 | | #define CURRENT_OPERAND1() (next_uop[-1].operand1) |
396 | | #define CURRENT_TARGET() (next_uop[-1].target) |
397 | | |
398 | | #define JUMP_TO_JUMP_TARGET() goto jump_to_jump_target |
399 | | #define JUMP_TO_ERROR() goto jump_to_error_target |
400 | | |
401 | | /* Stackref macros */ |
402 | | |
403 | | /* How much scratch space to give stackref to PyObject* conversion. */ |
404 | 2.00G | #define MAX_STACKREF_SCRATCH 10 |
405 | | |
406 | | #define STACKREFS_TO_PYOBJECTS(ARGS, ARG_COUNT, NAME) \ |
407 | | /* +1 because vectorcall might use -1 to write self */ \ |
408 | 2.00G | PyObject *NAME##_temp[MAX_STACKREF_SCRATCH+1]; \ |
409 | 2.00G | PyObject **NAME = _PyObjectArray_FromStackRefArray(ARGS, ARG_COUNT, NAME##_temp + 1); |
410 | | |
411 | | #define STACKREFS_TO_PYOBJECTS_CLEANUP(NAME) \ |
412 | | /* +1 because we +1 previously */ \ |
413 | 2.00G | _PyObjectArray_Free(NAME - 1, NAME##_temp); |
414 | | |
415 | 2.00G | #define CONVERSION_FAILED(NAME) ((NAME) == NULL) |
416 | | |
417 | | static inline int |
418 | 3.48G | check_periodics(PyThreadState *tstate) { |
419 | 3.48G | _Py_CHECK_EMSCRIPTEN_SIGNALS_PERIODICALLY(); |
420 | 3.48G | QSBR_QUIESCENT_STATE(tstate); |
421 | 3.48G | if (_Py_atomic_load_uintptr_relaxed(&tstate->eval_breaker) & _PY_EVAL_EVENTS_MASK) { |
422 | 30.0k | return _Py_HandlePending(tstate); |
423 | 30.0k | } |
424 | 3.48G | return 0; |
425 | 3.48G | } |
426 | | |