ref: 5bfce16c43b5f3e671a0ec1e9c6294bcc18353cf
dir: /sys/src/cmd/python/Python/ceval.c/
/* Execute compiled code */ /* XXX TO DO: XXX speed up searching for keywords by using a dictionary XXX document it! */ /* enable more aggressive intra-module optimizations, where available */ #define PY_LOCAL_AGGRESSIVE #include "Python.h" #include "code.h" #include "frameobject.h" #include "eval.h" #include "opcode.h" #include "structmember.h" #include <ctype.h> #ifndef WITH_TSC #define READ_TIMESTAMP(var) #else typedef unsigned long long uint64; #if defined(__ppc__) /* <- Don't know if this is the correct symbol; this section should work for GCC on any PowerPC platform, irrespective of OS. POWER? Who knows :-) */ #define READ_TIMESTAMP(var) ppc_getcounter(&var) static void ppc_getcounter(uint64 *v) { register unsigned long tbu, tb, tbu2; loop: asm volatile ("mftbu %0" : "=r" (tbu) ); asm volatile ("mftb %0" : "=r" (tb) ); asm volatile ("mftbu %0" : "=r" (tbu2)); if (__builtin_expect(tbu != tbu2, 0)) goto loop; /* The slightly peculiar way of writing the next lines is compiled better by GCC than any other way I tried. */ ((long*)(v))[0] = tbu; ((long*)(v))[1] = tb; } #else /* this is for linux/x86 (and probably any other GCC/x86 combo) */ #define READ_TIMESTAMP(val) \ __asm__ __volatile__("rdtsc" : "=A" (val)) #endif void dump_tsc(int opcode, int ticked, uint64 inst0, uint64 inst1, uint64 loop0, uint64 loop1, uint64 intr0, uint64 intr1) { uint64 intr, inst, loop; PyThreadState *tstate = PyThreadState_Get(); if (!tstate->interp->tscdump) return; intr = intr1 - intr0; inst = inst1 - inst0 - intr; loop = loop1 - loop0 - intr; fprintf(stderr, "opcode=%03d t=%d inst=%06lld loop=%06lld\n", opcode, ticked, inst, loop); } #endif /* Turn this on if your compiler chokes on the big switch: */ /* #define CASE_TOO_BIG 1 */ #ifdef Py_DEBUG /* For debugging the interpreter: */ #define LLTRACE 1 /* Low-level trace feature */ #define CHECKEXC 1 /* Double-check exception checking */ #endif typedef PyObject *(*callproc)(PyObject *, PyObject *, PyObject *); /* Forward declarations */ #ifdef WITH_TSC static PyObject * call_function(PyObject ***, int, uint64*, uint64*); #else static PyObject * call_function(PyObject ***, int); #endif static PyObject * fast_function(PyObject *, PyObject ***, int, int, int); static PyObject * do_call(PyObject *, PyObject ***, int, int); static PyObject * ext_do_call(PyObject *, PyObject ***, int, int, int); static PyObject * update_keyword_args(PyObject *, int, PyObject ***,PyObject *); static PyObject * update_star_args(int, int, PyObject *, PyObject ***); static PyObject * load_args(PyObject ***, int); #define CALL_FLAG_VAR 1 #define CALL_FLAG_KW 2 #ifdef LLTRACE static int lltrace; static int prtrace(PyObject *, char *); #endif static int call_trace(Py_tracefunc, PyObject *, PyFrameObject *, int, PyObject *); static void call_trace_protected(Py_tracefunc, PyObject *, PyFrameObject *, int, PyObject *); static void call_exc_trace(Py_tracefunc, PyObject *, PyFrameObject *); static int maybe_call_line_trace(Py_tracefunc, PyObject *, PyFrameObject *, int *, int *, int *); static PyObject * apply_slice(PyObject *, PyObject *, PyObject *); static int assign_slice(PyObject *, PyObject *, PyObject *, PyObject *); static PyObject * cmp_outcome(int, PyObject *, PyObject *); static PyObject * import_from(PyObject *, PyObject *); static int import_all_from(PyObject *, PyObject *); static PyObject * build_class(PyObject *, PyObject *, PyObject *); static int exec_statement(PyFrameObject *, PyObject *, PyObject *, PyObject *); static void set_exc_info(PyThreadState *, PyObject *, PyObject *, PyObject *); static void reset_exc_info(PyThreadState *); static void format_exc_check_arg(PyObject *, char *, PyObject *); static PyObject * string_concatenate(PyObject *, PyObject *, PyFrameObject *, unsigned char *); #define NAME_ERROR_MSG \ "name '%.200s' is not defined" #define GLOBAL_NAME_ERROR_MSG \ "global name '%.200s' is not defined" #define UNBOUNDLOCAL_ERROR_MSG \ "local variable '%.200s' referenced before assignment" #define UNBOUNDFREE_ERROR_MSG \ "free variable '%.200s' referenced before assignment" \ " in enclosing scope" /* Dynamic execution profile */ #ifdef DYNAMIC_EXECUTION_PROFILE #ifdef DXPAIRS static long dxpairs[257][256]; #define dxp dxpairs[256] #else static long dxp[256]; #endif #endif /* Function call profile */ #ifdef CALL_PROFILE #define PCALL_NUM 11 static int pcall[PCALL_NUM]; #define PCALL_ALL 0 #define PCALL_FUNCTION 1 #define PCALL_FAST_FUNCTION 2 #define PCALL_FASTER_FUNCTION 3 #define PCALL_METHOD 4 #define PCALL_BOUND_METHOD 5 #define PCALL_CFUNCTION 6 #define PCALL_TYPE 7 #define PCALL_GENERATOR 8 #define PCALL_OTHER 9 #define PCALL_POP 10 /* Notes about the statistics PCALL_FAST stats FAST_FUNCTION means no argument tuple needs to be created. FASTER_FUNCTION means that the fast-path frame setup code is used. If there is a method call where the call can be optimized by changing the argument tuple and calling the function directly, it gets recorded twice. As a result, the relationship among the statistics appears to be PCALL_ALL == PCALL_FUNCTION + PCALL_METHOD - PCALL_BOUND_METHOD + PCALL_CFUNCTION + PCALL_TYPE + PCALL_GENERATOR + PCALL_OTHER PCALL_FUNCTION > PCALL_FAST_FUNCTION > PCALL_FASTER_FUNCTION PCALL_METHOD > PCALL_BOUND_METHOD */ #define PCALL(POS) pcall[POS]++ PyObject * PyEval_GetCallStats(PyObject *self) { return Py_BuildValue("iiiiiiiiiii", pcall[0], pcall[1], pcall[2], pcall[3], pcall[4], pcall[5], pcall[6], pcall[7], pcall[8], pcall[9], pcall[10]); } #else #define PCALL(O) PyObject * PyEval_GetCallStats(PyObject *self) { Py_INCREF(Py_None); return Py_None; } #endif #ifdef WITH_THREAD #ifdef HAVE_ERRNO_H #include <errno.h> #endif #include "pythread.h" static PyThread_type_lock interpreter_lock = 0; /* This is the GIL */ static long main_thread = 0; int PyEval_ThreadsInitialized(void) { return interpreter_lock != 0; } void PyEval_InitThreads(void) { if (interpreter_lock) return; interpreter_lock = PyThread_allocate_lock(); PyThread_acquire_lock(interpreter_lock, 1); main_thread = PyThread_get_thread_ident(); } void PyEval_AcquireLock(void) { PyThread_acquire_lock(interpreter_lock, 1); } void PyEval_ReleaseLock(void) { PyThread_release_lock(interpreter_lock); } void PyEval_AcquireThread(PyThreadState *tstate) { if (tstate == NULL) Py_FatalError("PyEval_AcquireThread: NULL new thread state"); /* Check someone has called PyEval_InitThreads() to create the lock */ assert(interpreter_lock); PyThread_acquire_lock(interpreter_lock, 1); if (PyThreadState_Swap(tstate) != NULL) Py_FatalError( "PyEval_AcquireThread: non-NULL old thread state"); } void PyEval_ReleaseThread(PyThreadState *tstate) { if (tstate == NULL) Py_FatalError("PyEval_ReleaseThread: NULL thread state"); if (PyThreadState_Swap(NULL) != tstate) Py_FatalError("PyEval_ReleaseThread: wrong thread state"); PyThread_release_lock(interpreter_lock); } /* This function is called from PyOS_AfterFork to ensure that newly created child processes don't hold locks referring to threads which are not running in the child process. (This could also be done using pthread_atfork mechanism, at least for the pthreads implementation.) */ void PyEval_ReInitThreads(void) { if (!interpreter_lock) return; /*XXX Can't use PyThread_free_lock here because it does too much error-checking. Doing this cleanly would require adding a new function to each thread_*.h. Instead, just create a new lock and waste a little bit of memory */ interpreter_lock = PyThread_allocate_lock(); PyThread_acquire_lock(interpreter_lock, 1); main_thread = PyThread_get_thread_ident(); } #endif /* Functions save_thread and restore_thread are always defined so dynamically loaded modules needn't be compiled separately for use with and without threads: */ PyThreadState * PyEval_SaveThread(void) { PyThreadState *tstate = PyThreadState_Swap(NULL); if (tstate == NULL) Py_FatalError("PyEval_SaveThread: NULL tstate"); #ifdef WITH_THREAD if (interpreter_lock) PyThread_release_lock(interpreter_lock); #endif return tstate; } void PyEval_RestoreThread(PyThreadState *tstate) { if (tstate == NULL) Py_FatalError("PyEval_RestoreThread: NULL tstate"); #ifdef WITH_THREAD if (interpreter_lock) { int err = errno; PyThread_acquire_lock(interpreter_lock, 1); errno = err; } #endif PyThreadState_Swap(tstate); } /* Mechanism whereby asynchronously executing callbacks (e.g. UNIX signal handlers or Mac I/O completion routines) can schedule calls to a function to be called synchronously. The synchronous function is called with one void* argument. It should return 0 for success or -1 for failure -- failure should be accompanied by an exception. If registry succeeds, the registry function returns 0; if it fails (e.g. due to too many pending calls) it returns -1 (without setting an exception condition). Note that because registry may occur from within signal handlers, or other asynchronous events, calling malloc() is unsafe! #ifdef WITH_THREAD Any thread can schedule pending calls, but only the main thread will execute them. #endif XXX WARNING! ASYNCHRONOUSLY EXECUTING CODE! There are two possible race conditions: (1) nested asynchronous registry calls; (2) registry calls made while pending calls are being processed. While (1) is very unlikely, (2) is a real possibility. The current code is safe against (2), but not against (1). The safety against (2) is derived from the fact that only one thread (the main thread) ever takes things out of the queue. XXX Darn! With the advent of thread state, we should have an array of pending calls per thread in the thread state! Later... */ #define NPENDINGCALLS 32 static struct { int (*func)(void *); void *arg; } pendingcalls[NPENDINGCALLS]; static volatile int pendingfirst = 0; static volatile int pendinglast = 0; static volatile int things_to_do = 0; int Py_AddPendingCall(int (*func)(void *), void *arg) { static int busy = 0; int i, j; /* XXX Begin critical section */ /* XXX If you want this to be safe against nested XXX asynchronous calls, you'll have to work harder! */ if (busy) return -1; busy = 1; i = pendinglast; j = (i + 1) % NPENDINGCALLS; if (j == pendingfirst) { busy = 0; return -1; /* Queue full */ } pendingcalls[i].func = func; pendingcalls[i].arg = arg; pendinglast = j; _Py_Ticker = 0; things_to_do = 1; /* Signal main loop */ busy = 0; /* XXX End critical section */ return 0; } int Py_MakePendingCalls(void) { static int busy = 0; #ifdef WITH_THREAD if (main_thread && PyThread_get_thread_ident() != main_thread) return 0; #endif if (busy) return 0; busy = 1; things_to_do = 0; for (;;) { int i; int (*func)(void *); void *arg; i = pendingfirst; if (i == pendinglast) break; /* Queue empty */ func = pendingcalls[i].func; arg = pendingcalls[i].arg; pendingfirst = (i + 1) % NPENDINGCALLS; if (func(arg) < 0) { busy = 0; things_to_do = 1; /* We're not done yet */ return -1; } } busy = 0; return 0; } /* The interpreter's recursion limit */ #ifndef Py_DEFAULT_RECURSION_LIMIT #define Py_DEFAULT_RECURSION_LIMIT 1000 #endif static int recursion_limit = Py_DEFAULT_RECURSION_LIMIT; int _Py_CheckRecursionLimit = Py_DEFAULT_RECURSION_LIMIT; int Py_GetRecursionLimit(void) { return recursion_limit; } void Py_SetRecursionLimit(int new_limit) { recursion_limit = new_limit; _Py_CheckRecursionLimit = recursion_limit; } /* the macro Py_EnterRecursiveCall() only calls _Py_CheckRecursiveCall() if the recursion_depth reaches _Py_CheckRecursionLimit. If USE_STACKCHECK, the macro decrements _Py_CheckRecursionLimit to guarantee that _Py_CheckRecursiveCall() is regularly called. Without USE_STACKCHECK, there is no need for this. */ int _Py_CheckRecursiveCall(char *where) { PyThreadState *tstate = PyThreadState_GET(); #ifdef USE_STACKCHECK if (PyOS_CheckStack()) { --tstate->recursion_depth; PyErr_SetString(PyExc_MemoryError, "Stack overflow"); return -1; } #endif if (tstate->recursion_depth > recursion_limit) { --tstate->recursion_depth; PyErr_Format(PyExc_RuntimeError, "maximum recursion depth exceeded%s", where); return -1; } _Py_CheckRecursionLimit = recursion_limit; return 0; } /* Status code for main loop (reason for stack unwind) */ enum why_code { WHY_NOT = 0x0001, /* No error */ WHY_EXCEPTION = 0x0002, /* Exception occurred */ WHY_RERAISE = 0x0004, /* Exception re-raised by 'finally' */ WHY_RETURN = 0x0008, /* 'return' statement */ WHY_BREAK = 0x0010, /* 'break' statement */ WHY_CONTINUE = 0x0020, /* 'continue' statement */ WHY_YIELD = 0x0040 /* 'yield' operator */ }; static enum why_code do_raise(PyObject *, PyObject *, PyObject *); static int unpack_iterable(PyObject *, int, PyObject **); /* for manipulating the thread switch and periodic "stuff" - used to be per thread, now just a pair o' globals */ int _Py_CheckInterval = 100; volatile int _Py_Ticker = 100; PyObject * PyEval_EvalCode(PyCodeObject *co, PyObject *globals, PyObject *locals) { /* XXX raise SystemError if globals is NULL */ return PyEval_EvalCodeEx(co, globals, locals, (PyObject **)NULL, 0, (PyObject **)NULL, 0, (PyObject **)NULL, 0, NULL); } /* Interpreter main loop */ PyObject * PyEval_EvalFrame(PyFrameObject *f) { /* This is for backward compatibility with extension modules that used this API; core interpreter code should call PyEval_EvalFrameEx() */ return PyEval_EvalFrameEx(f, 0); } PyObject * PyEval_EvalFrameEx(PyFrameObject *f, int throwflag) { #ifdef DXPAIRS int lastopcode = 0; #endif register PyObject **stack_pointer; /* Next free slot in value stack */ register unsigned char *next_instr; register int opcode; /* Current opcode */ register int oparg; /* Current opcode argument, if any */ register enum why_code why; /* Reason for block stack unwind */ register int err; /* Error status -- nonzero if error */ register PyObject *x; /* Result object -- NULL if error */ register PyObject *v; /* Temporary objects popped off stack */ register PyObject *w; register PyObject *u; register PyObject *t; register PyObject *stream = NULL; /* for PRINT opcodes */ register PyObject **fastlocals, **freevars; PyObject *retval = NULL; /* Return value */ PyThreadState *tstate = PyThreadState_GET(); PyCodeObject *co; /* when tracing we set things up so that not (instr_lb <= current_bytecode_offset < instr_ub) is true when the line being executed has changed. The initial values are such as to make this false the first time it is tested. */ int instr_ub = -1, instr_lb = 0, instr_prev = -1; unsigned char *first_instr; PyObject *names; PyObject *consts; #if defined(Py_DEBUG) || defined(LLTRACE) /* Make it easier to find out where we are with a debugger */ char *filename; #endif /* Tuple access macros */ #ifndef Py_DEBUG #define GETITEM(v, i) PyTuple_GET_ITEM((PyTupleObject *)(v), (i)) #else #define GETITEM(v, i) PyTuple_GetItem((v), (i)) #endif #ifdef WITH_TSC /* Use Pentium timestamp counter to mark certain events: inst0 -- beginning of switch statement for opcode dispatch inst1 -- end of switch statement (may be skipped) loop0 -- the top of the mainloop loop1 -- place where control returns again to top of mainloop (may be skipped) intr1 -- beginning of long interruption intr2 -- end of long interruption Many opcodes call out to helper C functions. In some cases, the time in those functions should be counted towards the time for the opcode, but not in all cases. For example, a CALL_FUNCTION opcode calls another Python function; there's no point in charge all the bytecode executed by the called function to the caller. It's hard to make a useful judgement statically. In the presence of operator overloading, it's impossible to tell if a call will execute new Python code or not. It's a case-by-case judgement. I'll use intr1 for the following cases: EXEC_STMT IMPORT_STAR IMPORT_FROM CALL_FUNCTION (and friends) */ uint64 inst0, inst1, loop0, loop1, intr0 = 0, intr1 = 0; int ticked = 0; READ_TIMESTAMP(inst0); READ_TIMESTAMP(inst1); READ_TIMESTAMP(loop0); READ_TIMESTAMP(loop1); /* shut up the compiler */ opcode = 0; #endif /* Code access macros */ #define INSTR_OFFSET() ((int)(next_instr - first_instr)) #define NEXTOP() (*next_instr++) #define NEXTARG() (next_instr += 2, (next_instr[-1]<<8) + next_instr[-2]) #define PEEKARG() ((next_instr[2]<<8) + next_instr[1]) #define JUMPTO(x) (next_instr = first_instr + (x)) #define JUMPBY(x) (next_instr += (x)) /* OpCode prediction macros Some opcodes tend to come in pairs thus making it possible to predict the second code when the first is run. For example, COMPARE_OP is often followed by JUMP_IF_FALSE or JUMP_IF_TRUE. And, those opcodes are often followed by a POP_TOP. Verifying the prediction costs a single high-speed test of register variable against a constant. If the pairing was good, then the processor has a high likelihood of making its own successful branch prediction which results in a nearly zero overhead transition to the next opcode. A successful prediction saves a trip through the eval-loop including its two unpredictable branches, the HASARG test and the switch-case. If collecting opcode statistics, turn off prediction so that statistics are accurately maintained (the predictions bypass the opcode frequency counter updates). */ #ifdef DYNAMIC_EXECUTION_PROFILE #define PREDICT(op) if (0) goto PRED_##op #else #define PREDICT(op) if (*next_instr == op) goto PRED_##op #endif #define PREDICTED(op) PRED_##op: next_instr++ #define PREDICTED_WITH_ARG(op) PRED_##op: oparg = PEEKARG(); next_instr += 3 /* Stack manipulation macros */ /* The stack can grow at most MAXINT deep, as co_nlocals and co_stacksize are ints. */ #define STACK_LEVEL() ((int)(stack_pointer - f->f_valuestack)) #define EMPTY() (STACK_LEVEL() == 0) #define TOP() (stack_pointer[-1]) #define SECOND() (stack_pointer[-2]) #define THIRD() (stack_pointer[-3]) #define FOURTH() (stack_pointer[-4]) #define SET_TOP(v) (stack_pointer[-1] = (v)) #define SET_SECOND(v) (stack_pointer[-2] = (v)) #define SET_THIRD(v) (stack_pointer[-3] = (v)) #define SET_FOURTH(v) (stack_pointer[-4] = (v)) #define BASIC_STACKADJ(n) (stack_pointer += n) #define BASIC_PUSH(v) (*stack_pointer++ = (v)) #define BASIC_POP() (*--stack_pointer) #ifdef LLTRACE #define PUSH(v) { (void)(BASIC_PUSH(v), \ lltrace && prtrace(TOP(), "push")); \ assert(STACK_LEVEL() <= co->co_stacksize); } #define POP() ((void)(lltrace && prtrace(TOP(), "pop")), BASIC_POP()) #define STACKADJ(n) { (void)(BASIC_STACKADJ(n), \ lltrace && prtrace(TOP(), "stackadj")); \ assert(STACK_LEVEL() <= co->co_stacksize); } #define EXT_POP(STACK_POINTER) (lltrace && prtrace(*(STACK_POINTER), "ext_pop"), *--(STACK_POINTER)) #else #define PUSH(v) BASIC_PUSH(v) #define POP() BASIC_POP() #define STACKADJ(n) BASIC_STACKADJ(n) #define EXT_POP(STACK_POINTER) (*--(STACK_POINTER)) #endif /* Local variable macros */ #define GETLOCAL(i) (fastlocals[i]) /* The SETLOCAL() macro must not DECREF the local variable in-place and then store the new value; it must copy the old value to a temporary value, then store the new value, and then DECREF the temporary value. This is because it is possible that during the DECREF the frame is accessed by other code (e.g. a __del__ method or gc.collect()) and the variable would be pointing to already-freed memory. */ #define SETLOCAL(i, value) do { PyObject *tmp = GETLOCAL(i); \ GETLOCAL(i) = value; \ Py_XDECREF(tmp); } while (0) /* Start of code */ if (f == NULL) return NULL; /* push frame */ if (Py_EnterRecursiveCall("")) return NULL; tstate->frame = f; if (tstate->use_tracing) { if (tstate->c_tracefunc != NULL) { /* tstate->c_tracefunc, if defined, is a function that will be called on *every* entry to a code block. Its return value, if not None, is a function that will be called at the start of each executed line of code. (Actually, the function must return itself in order to continue tracing.) The trace functions are called with three arguments: a pointer to the current frame, a string indicating why the function is called, and an argument which depends on the situation. The global trace function is also called whenever an exception is detected. */ if (call_trace(tstate->c_tracefunc, tstate->c_traceobj, f, PyTrace_CALL, Py_None)) { /* Trace function raised an error */ goto exit_eval_frame; } } if (tstate->c_profilefunc != NULL) { /* Similar for c_profilefunc, except it needn't return itself and isn't called for "line" events */ if (call_trace(tstate->c_profilefunc, tstate->c_profileobj, f, PyTrace_CALL, Py_None)) { /* Profile function raised an error */ goto exit_eval_frame; } } } co = f->f_code; names = co->co_names; consts = co->co_consts; fastlocals = f->f_localsplus; freevars = f->f_localsplus + co->co_nlocals; first_instr = (unsigned char*) PyString_AS_STRING(co->co_code); /* An explanation is in order for the next line. f->f_lasti now refers to the index of the last instruction executed. You might think this was obvious from the name, but this wasn't always true before 2.3! PyFrame_New now sets f->f_lasti to -1 (i.e. the index *before* the first instruction) and YIELD_VALUE doesn't fiddle with f_lasti any more. So this does work. Promise. */ next_instr = first_instr + f->f_lasti + 1; stack_pointer = f->f_stacktop; assert(stack_pointer != NULL); f->f_stacktop = NULL; /* remains NULL unless yield suspends frame */ #ifdef LLTRACE lltrace = PyDict_GetItemString(f->f_globals, "__lltrace__") != NULL; #endif #if defined(Py_DEBUG) || defined(LLTRACE) filename = PyString_AsString(co->co_filename); #endif why = WHY_NOT; err = 0; x = Py_None; /* Not a reference, just anything non-NULL */ w = NULL; if (throwflag) { /* support for generator.throw() */ why = WHY_EXCEPTION; goto on_error; } for (;;) { #ifdef WITH_TSC if (inst1 == 0) { /* Almost surely, the opcode executed a break or a continue, preventing inst1 from being set on the way out of the loop. */ READ_TIMESTAMP(inst1); loop1 = inst1; } dump_tsc(opcode, ticked, inst0, inst1, loop0, loop1, intr0, intr1); ticked = 0; inst1 = 0; intr0 = 0; intr1 = 0; READ_TIMESTAMP(loop0); #endif assert(stack_pointer >= f->f_valuestack); /* else underflow */ assert(STACK_LEVEL() <= co->co_stacksize); /* else overflow */ /* Do periodic things. Doing this every time through the loop would add too much overhead, so we do it only every Nth instruction. We also do it if ``things_to_do'' is set, i.e. when an asynchronous event needs attention (e.g. a signal handler or async I/O handler); see Py_AddPendingCall() and Py_MakePendingCalls() above. */ if (--_Py_Ticker < 0) { if (*next_instr == SETUP_FINALLY) { /* Make the last opcode before a try: finally: block uninterruptable. */ goto fast_next_opcode; } _Py_Ticker = _Py_CheckInterval; tstate->tick_counter++; #ifdef WITH_TSC ticked = 1; #endif if (things_to_do) { if (Py_MakePendingCalls() < 0) { why = WHY_EXCEPTION; goto on_error; } if (things_to_do) /* MakePendingCalls() didn't succeed. Force early re-execution of this "periodic" code, possibly after a thread switch */ _Py_Ticker = 0; } #ifdef WITH_THREAD if (interpreter_lock) { /* Give another thread a chance */ if (PyThreadState_Swap(NULL) != tstate) Py_FatalError("ceval: tstate mix-up"); PyThread_release_lock(interpreter_lock); /* Other threads may run now */ PyThread_acquire_lock(interpreter_lock, 1); if (PyThreadState_Swap(tstate) != NULL) Py_FatalError("ceval: orphan tstate"); /* Check for thread interrupts */ if (tstate->async_exc != NULL) { x = tstate->async_exc; tstate->async_exc = NULL; PyErr_SetNone(x); Py_DECREF(x); why = WHY_EXCEPTION; goto on_error; } } #endif } fast_next_opcode: f->f_lasti = INSTR_OFFSET(); /* line-by-line tracing support */ if (tstate->c_tracefunc != NULL && !tstate->tracing) { /* see maybe_call_line_trace for expository comments */ f->f_stacktop = stack_pointer; err = maybe_call_line_trace(tstate->c_tracefunc, tstate->c_traceobj, f, &instr_lb, &instr_ub, &instr_prev); /* Reload possibly changed frame fields */ JUMPTO(f->f_lasti); if (f->f_stacktop != NULL) { stack_pointer = f->f_stacktop; f->f_stacktop = NULL; } if (err) { /* trace function raised an exception */ goto on_error; } } /* Extract opcode and argument */ opcode = NEXTOP(); oparg = 0; /* allows oparg to be stored in a register because it doesn't have to be remembered across a full loop */ if (HAS_ARG(opcode)) oparg = NEXTARG(); dispatch_opcode: #ifdef DYNAMIC_EXECUTION_PROFILE #ifdef DXPAIRS dxpairs[lastopcode][opcode]++; lastopcode = opcode; #endif dxp[opcode]++; #endif #ifdef LLTRACE /* Instruction tracing */ if (lltrace) { if (HAS_ARG(opcode)) { printf("%d: %d, %d\n", f->f_lasti, opcode, oparg); } else { printf("%d: %d\n", f->f_lasti, opcode); } } #endif /* Main switch on opcode */ READ_TIMESTAMP(inst0); switch (opcode) { /* BEWARE! It is essential that any operation that fails sets either x to NULL, err to nonzero, or why to anything but WHY_NOT, and that no operation that succeeds does this! */ /* case STOP_CODE: this is an error! */ case NOP: goto fast_next_opcode; case LOAD_FAST: x = GETLOCAL(oparg); if (x != NULL) { Py_INCREF(x); PUSH(x); goto fast_next_opcode; } format_exc_check_arg(PyExc_UnboundLocalError, UNBOUNDLOCAL_ERROR_MSG, PyTuple_GetItem(co->co_varnames, oparg)); break; case LOAD_CONST: x = GETITEM(consts, oparg); Py_INCREF(x); PUSH(x); goto fast_next_opcode; PREDICTED_WITH_ARG(STORE_FAST); case STORE_FAST: v = POP(); SETLOCAL(oparg, v); goto fast_next_opcode; PREDICTED(POP_TOP); case POP_TOP: v = POP(); Py_DECREF(v); goto fast_next_opcode; case ROT_TWO: v = TOP(); w = SECOND(); SET_TOP(w); SET_SECOND(v); goto fast_next_opcode; case ROT_THREE: v = TOP(); w = SECOND(); x = THIRD(); SET_TOP(w); SET_SECOND(x); SET_THIRD(v); goto fast_next_opcode; case ROT_FOUR: u = TOP(); v = SECOND(); w = THIRD(); x = FOURTH(); SET_TOP(v); SET_SECOND(w); SET_THIRD(x); SET_FOURTH(u); goto fast_next_opcode; case DUP_TOP: v = TOP(); Py_INCREF(v); PUSH(v); goto fast_next_opcode; case DUP_TOPX: if (oparg == 2) { x = TOP(); Py_INCREF(x); w = SECOND(); Py_INCREF(w); STACKADJ(2); SET_TOP(x); SET_SECOND(w); goto fast_next_opcode; } else if (oparg == 3) { x = TOP(); Py_INCREF(x); w = SECOND(); Py_INCREF(w); v = THIRD(); Py_INCREF(v); STACKADJ(3); SET_TOP(x); SET_SECOND(w); SET_THIRD(v); goto fast_next_opcode; } Py_FatalError("invalid argument to DUP_TOPX" " (bytecode corruption?)"); break; case UNARY_POSITIVE: v = TOP(); x = PyNumber_Positive(v); Py_DECREF(v); SET_TOP(x); if (x != NULL) continue; break; case UNARY_NEGATIVE: v = TOP(); x = PyNumber_Negative(v); Py_DECREF(v); SET_TOP(x); if (x != NULL) continue; break; case UNARY_NOT: v = TOP(); err = PyObject_IsTrue(v); Py_DECREF(v); if (err == 0) { Py_INCREF(Py_True); SET_TOP(Py_True); continue; } else if (err > 0) { Py_INCREF(Py_False); SET_TOP(Py_False); err = 0; continue; } STACKADJ(-1); break; case UNARY_CONVERT: v = TOP(); x = PyObject_Repr(v); Py_DECREF(v); SET_TOP(x); if (x != NULL) continue; break; case UNARY_INVERT: v = TOP(); x = PyNumber_Invert(v); Py_DECREF(v); SET_TOP(x); if (x != NULL) continue; break; case BINARY_POWER: w = POP(); v = TOP(); x = PyNumber_Power(v, w, Py_None); Py_DECREF(v); Py_DECREF(w); SET_TOP(x); if (x != NULL) continue; break; case BINARY_MULTIPLY: w = POP(); v = TOP(); x = PyNumber_Multiply(v, w); Py_DECREF(v); Py_DECREF(w); SET_TOP(x); if (x != NULL) continue; break; case BINARY_DIVIDE: if (!_Py_QnewFlag) { w = POP(); v = TOP(); x = PyNumber_Divide(v, w); Py_DECREF(v); Py_DECREF(w); SET_TOP(x); if (x != NULL) continue; break; } /* -Qnew is in effect: fall through to BINARY_TRUE_DIVIDE */ case BINARY_TRUE_DIVIDE: w = POP(); v = TOP(); x = PyNumber_TrueDivide(v, w); Py_DECREF(v); Py_DECREF(w); SET_TOP(x); if (x != NULL) continue; break; case BINARY_FLOOR_DIVIDE: w = POP(); v = TOP(); x = PyNumber_FloorDivide(v, w); Py_DECREF(v); Py_DECREF(w); SET_TOP(x); if (x != NULL) continue; break; case BINARY_MODULO: w = POP(); v = TOP(); x = PyNumber_Remainder(v, w); Py_DECREF(v); Py_DECREF(w); SET_TOP(x); if (x != NULL) continue; break; case BINARY_ADD: w = POP(); v = TOP(); if (PyInt_CheckExact(v) && PyInt_CheckExact(w)) { /* INLINE: int + int */ register long a, b, i; a = PyInt_AS_LONG(v); b = PyInt_AS_LONG(w); i = a + b; if ((i^a) < 0 && (i^b) < 0) goto slow_add; x = PyInt_FromLong(i); } else if (PyString_CheckExact(v) && PyString_CheckExact(w)) { x = string_concatenate(v, w, f, next_instr); /* string_concatenate consumed the ref to v */ goto skip_decref_vx; } else { slow_add: x = PyNumber_Add(v, w); } Py_DECREF(v); skip_decref_vx: Py_DECREF(w); SET_TOP(x); if (x != NULL) continue; break; case BINARY_SUBTRACT: w = POP(); v = TOP(); if (PyInt_CheckExact(v) && PyInt_CheckExact(w)) { /* INLINE: int - int */ register long a, b, i; a = PyInt_AS_LONG(v); b = PyInt_AS_LONG(w); i = a - b; if ((i^a) < 0 && (i^~b) < 0) goto slow_sub; x = PyInt_FromLong(i); } else { slow_sub: x = PyNumber_Subtract(v, w); } Py_DECREF(v); Py_DECREF(w); SET_TOP(x); if (x != NULL) continue; break; case BINARY_SUBSCR: w = POP(); v = TOP(); if (PyList_CheckExact(v) && PyInt_CheckExact(w)) { /* INLINE: list[int] */ Py_ssize_t i = PyInt_AsSsize_t(w); if (i < 0) i += PyList_GET_SIZE(v); if (i >= 0 && i < PyList_GET_SIZE(v)) { x = PyList_GET_ITEM(v, i); Py_INCREF(x); } else goto slow_get; } else slow_get: x = PyObject_GetItem(v, w); Py_DECREF(v); Py_DECREF(w); SET_TOP(x); if (x != NULL) continue; break; case BINARY_LSHIFT: w = POP(); v = TOP(); x = PyNumber_Lshift(v, w); Py_DECREF(v); Py_DECREF(w); SET_TOP(x); if (x != NULL) continue; break; case BINARY_RSHIFT: w = POP(); v = TOP(); x = PyNumber_Rshift(v, w); Py_DECREF(v); Py_DECREF(w); SET_TOP(x); if (x != NULL) continue; break; case BINARY_AND: w = POP(); v = TOP(); x = PyNumber_And(v, w); Py_DECREF(v); Py_DECREF(w); SET_TOP(x); if (x != NULL) continue; break; case BINARY_XOR: w = POP(); v = TOP(); x = PyNumber_Xor(v, w); Py_DECREF(v); Py_DECREF(w); SET_TOP(x); if (x != NULL) continue; break; case BINARY_OR: w = POP(); v = TOP(); x = PyNumber_Or(v, w); Py_DECREF(v); Py_DECREF(w); SET_TOP(x); if (x != NULL) continue; break; case LIST_APPEND: w = POP(); v = POP(); err = PyList_Append(v, w); Py_DECREF(v); Py_DECREF(w); if (err == 0) { PREDICT(JUMP_ABSOLUTE); continue; } break; case INPLACE_POWER: w = POP(); v = TOP(); x = PyNumber_InPlacePower(v, w, Py_None); Py_DECREF(v); Py_DECREF(w); SET_TOP(x); if (x != NULL) continue; break; case INPLACE_MULTIPLY: w = POP(); v = TOP(); x = PyNumber_InPlaceMultiply(v, w); Py_DECREF(v); Py_DECREF(w); SET_TOP(x); if (x != NULL) continue; break; case INPLACE_DIVIDE: if (!_Py_QnewFlag) { w = POP(); v = TOP(); x = PyNumber_InPlaceDivide(v, w); Py_DECREF(v); Py_DECREF(w); SET_TOP(x); if (x != NULL) continue; break; } /* -Qnew is in effect: fall through to INPLACE_TRUE_DIVIDE */ case INPLACE_TRUE_DIVIDE: w = POP(); v = TOP(); x = PyNumber_InPlaceTrueDivide(v, w); Py_DECREF(v); Py_DECREF(w); SET_TOP(x); if (x != NULL) continue; break; case INPLACE_FLOOR_DIVIDE: w = POP(); v = TOP(); x = PyNumber_InPlaceFloorDivide(v, w); Py_DECREF(v); Py_DECREF(w); SET_TOP(x); if (x != NULL) continue; break; case INPLACE_MODULO: w = POP(); v = TOP(); x = PyNumber_InPlaceRemainder(v, w); Py_DECREF(v); Py_DECREF(w); SET_TOP(x); if (x != NULL) continue; break; case INPLACE_ADD: w = POP(); v = TOP(); if (PyInt_CheckExact(v) && PyInt_CheckExact(w)) { /* INLINE: int + int */ register long a, b, i; a = PyInt_AS_LONG(v); b = PyInt_AS_LONG(w); i = a + b; if ((i^a) < 0 && (i^b) < 0) goto slow_iadd; x = PyInt_FromLong(i); } else if (PyString_CheckExact(v) && PyString_CheckExact(w)) { x = string_concatenate(v, w, f, next_instr); /* string_concatenate consumed the ref to v */ goto skip_decref_v; } else { slow_iadd: x = PyNumber_InPlaceAdd(v, w); } Py_DECREF(v); skip_decref_v: Py_DECREF(w); SET_TOP(x); if (x != NULL) continue; break; case INPLACE_SUBTRACT: w = POP(); v = TOP(); if (PyInt_CheckExact(v) && PyInt_CheckExact(w)) { /* INLINE: int - int */ register long a, b, i; a = PyInt_AS_LONG(v); b = PyInt_AS_LONG(w); i = a - b; if ((i^a) < 0 && (i^~b) < 0) goto slow_isub; x = PyInt_FromLong(i); } else { slow_isub: x = PyNumber_InPlaceSubtract(v, w); } Py_DECREF(v); Py_DECREF(w); SET_TOP(x); if (x != NULL) continue; break; case INPLACE_LSHIFT: w = POP(); v = TOP(); x = PyNumber_InPlaceLshift(v, w); Py_DECREF(v); Py_DECREF(w); SET_TOP(x); if (x != NULL) continue; break; case INPLACE_RSHIFT: w = POP(); v = TOP(); x = PyNumber_InPlaceRshift(v, w); Py_DECREF(v); Py_DECREF(w); SET_TOP(x); if (x != NULL) continue; break; case INPLACE_AND: w = POP(); v = TOP(); x = PyNumber_InPlaceAnd(v, w); Py_DECREF(v); Py_DECREF(w); SET_TOP(x); if (x != NULL) continue; break; case INPLACE_XOR: w = POP(); v = TOP(); x = PyNumber_InPlaceXor(v, w); Py_DECREF(v); Py_DECREF(w); SET_TOP(x); if (x != NULL) continue; break; case INPLACE_OR: w = POP(); v = TOP(); x = PyNumber_InPlaceOr(v, w); Py_DECREF(v); Py_DECREF(w); SET_TOP(x); if (x != NULL) continue; break; case SLICE+0: case SLICE+1: case SLICE+2: case SLICE+3: if ((opcode-SLICE) & 2) w = POP(); else w = NULL; if ((opcode-SLICE) & 1) v = POP(); else v = NULL; u = TOP(); x = apply_slice(u, v, w); Py_DECREF(u); Py_XDECREF(v); Py_XDECREF(w); SET_TOP(x); if (x != NULL) continue; break; case STORE_SLICE+0: case STORE_SLICE+1: case STORE_SLICE+2: case STORE_SLICE+3: if ((opcode-STORE_SLICE) & 2) w = POP(); else w = NULL; if ((opcode-STORE_SLICE) & 1) v = POP(); else v = NULL; u = POP(); t = POP(); err = assign_slice(u, v, w, t); /* u[v:w] = t */ Py_DECREF(t); Py_DECREF(u); Py_XDECREF(v); Py_XDECREF(w); if (err == 0) continue; break; case DELETE_SLICE+0: case DELETE_SLICE+1: case DELETE_SLICE+2: case DELETE_SLICE+3: if ((opcode-DELETE_SLICE) & 2) w = POP(); else w = NULL; if ((opcode-DELETE_SLICE) & 1) v = POP(); else v = NULL; u = POP(); err = assign_slice(u, v, w, (PyObject *)NULL); /* del u[v:w] */ Py_DECREF(u); Py_XDECREF(v); Py_XDECREF(w); if (err == 0) continue; break; case STORE_SUBSCR: w = TOP(); v = SECOND(); u = THIRD(); STACKADJ(-3); /* v[w] = u */ err = PyObject_SetItem(v, w, u); Py_DECREF(u); Py_DECREF(v); Py_DECREF(w); if (err == 0) continue; break; case DELETE_SUBSCR: w = TOP(); v = SECOND(); STACKADJ(-2); /* del v[w] */ err = PyObject_DelItem(v, w); Py_DECREF(v); Py_DECREF(w); if (err == 0) continue; break; case PRINT_EXPR: v = POP(); w = PySys_GetObject("displayhook"); if (w == NULL) { PyErr_SetString(PyExc_RuntimeError, "lost sys.displayhook"); err = -1; x = NULL; } if (err == 0) { x = PyTuple_Pack(1, v); if (x == NULL) err = -1; } if (err == 0) { w = PyEval_CallObject(w, x); Py_XDECREF(w); if (w == NULL) err = -1; } Py_DECREF(v); Py_XDECREF(x); break; case PRINT_ITEM_TO: w = stream = POP(); /* fall through to PRINT_ITEM */ case PRINT_ITEM: v = POP(); if (stream == NULL || stream == Py_None) { w = PySys_GetObject("stdout"); if (w == NULL) { PyErr_SetString(PyExc_RuntimeError, "lost sys.stdout"); err = -1; } } /* PyFile_SoftSpace() can exececute arbitrary code if sys.stdout is an instance with a __getattr__. If __getattr__ raises an exception, w will be freed, so we need to prevent that temporarily. */ Py_XINCREF(w); if (w != NULL && PyFile_SoftSpace(w, 0)) err = PyFile_WriteString(" ", w); if (err == 0) err = PyFile_WriteObject(v, w, Py_PRINT_RAW); if (err == 0) { /* XXX move into writeobject() ? */ if (PyString_Check(v)) { char *s = PyString_AS_STRING(v); Py_ssize_t len = PyString_GET_SIZE(v); if (len == 0 || !isspace(Py_CHARMASK(s[len-1])) || s[len-1] == ' ') PyFile_SoftSpace(w, 1); } #ifdef Py_USING_UNICODE else if (PyUnicode_Check(v)) { Py_UNICODE *s = PyUnicode_AS_UNICODE(v); Py_ssize_t len = PyUnicode_GET_SIZE(v); if (len == 0 || !Py_UNICODE_ISSPACE(s[len-1]) || s[len-1] == ' ') PyFile_SoftSpace(w, 1); } #endif else PyFile_SoftSpace(w, 1); } Py_XDECREF(w); Py_DECREF(v); Py_XDECREF(stream); stream = NULL; if (err == 0) continue; break; case PRINT_NEWLINE_TO: w = stream = POP(); /* fall through to PRINT_NEWLINE */ case PRINT_NEWLINE: if (stream == NULL || stream == Py_None) { w = PySys_GetObject("stdout"); if (w == NULL) PyErr_SetString(PyExc_RuntimeError, "lost sys.stdout"); } if (w != NULL) { err = PyFile_WriteString("\n", w); if (err == 0) PyFile_SoftSpace(w, 0); } Py_XDECREF(stream); stream = NULL; break; #ifdef CASE_TOO_BIG default: switch (opcode) { #endif case RAISE_VARARGS: u = v = w = NULL; switch (oparg) { case 3: u = POP(); /* traceback */ /* Fallthrough */ case 2: v = POP(); /* value */ /* Fallthrough */ case 1: w = POP(); /* exc */ case 0: /* Fallthrough */ why = do_raise(w, v, u); break; default: PyErr_SetString(PyExc_SystemError, "bad RAISE_VARARGS oparg"); why = WHY_EXCEPTION; break; } break; case LOAD_LOCALS: if ((x = f->f_locals) != NULL) { Py_INCREF(x); PUSH(x); continue; } PyErr_SetString(PyExc_SystemError, "no locals"); break; case RETURN_VALUE: retval = POP(); why = WHY_RETURN; goto fast_block_end; case YIELD_VALUE: retval = POP(); f->f_stacktop = stack_pointer; why = WHY_YIELD; goto fast_yield; case EXEC_STMT: w = TOP(); v = SECOND(); u = THIRD(); STACKADJ(-3); READ_TIMESTAMP(intr0); err = exec_statement(f, u, v, w); READ_TIMESTAMP(intr1); Py_DECREF(u); Py_DECREF(v); Py_DECREF(w); break; case POP_BLOCK: { PyTryBlock *b = PyFrame_BlockPop(f); while (STACK_LEVEL() > b->b_level) { v = POP(); Py_DECREF(v); } } continue; case END_FINALLY: v = POP(); if (PyInt_Check(v)) { why = (enum why_code) PyInt_AS_LONG(v); assert(why != WHY_YIELD); if (why == WHY_RETURN || why == WHY_CONTINUE) retval = POP(); } else if (PyExceptionClass_Check(v) || PyString_Check(v)) { w = POP(); u = POP(); PyErr_Restore(v, w, u); why = WHY_RERAISE; break; } else if (v != Py_None) { PyErr_SetString(PyExc_SystemError, "'finally' pops bad exception"); why = WHY_EXCEPTION; } Py_DECREF(v); break; case BUILD_CLASS: u = TOP(); v = SECOND(); w = THIRD(); STACKADJ(-2); x = build_class(u, v, w); SET_TOP(x); Py_DECREF(u); Py_DECREF(v); Py_DECREF(w); break; case STORE_NAME: w = GETITEM(names, oparg); v = POP(); if ((x = f->f_locals) != NULL) { if (PyDict_CheckExact(x)) err = PyDict_SetItem(x, w, v); else err = PyObject_SetItem(x, w, v); Py_DECREF(v); if (err == 0) continue; break; } PyErr_Format(PyExc_SystemError, "no locals found when storing %s", PyObject_REPR(w)); break; case DELETE_NAME: w = GETITEM(names, oparg); if ((x = f->f_locals) != NULL) { if ((err = PyObject_DelItem(x, w)) != 0) format_exc_check_arg(PyExc_NameError, NAME_ERROR_MSG ,w); break; } PyErr_Format(PyExc_SystemError, "no locals when deleting %s", PyObject_REPR(w)); break; PREDICTED_WITH_ARG(UNPACK_SEQUENCE); case UNPACK_SEQUENCE: v = POP(); if (PyTuple_CheckExact(v) && PyTuple_GET_SIZE(v) == oparg) { PyObject **items = ((PyTupleObject *)v)->ob_item; while (oparg--) { w = items[oparg]; Py_INCREF(w); PUSH(w); } Py_DECREF(v); continue; } else if (PyList_CheckExact(v) && PyList_GET_SIZE(v) == oparg) { PyObject **items = ((PyListObject *)v)->ob_item; while (oparg--) { w = items[oparg]; Py_INCREF(w); PUSH(w); } } else if (unpack_iterable(v, oparg, stack_pointer + oparg)) { stack_pointer += oparg; } else { /* unpack_iterable() raised an exception */ why = WHY_EXCEPTION; } Py_DECREF(v); break; case STORE_ATTR: w = GETITEM(names, oparg); v = TOP(); u = SECOND(); STACKADJ(-2); err = PyObject_SetAttr(v, w, u); /* v.w = u */ Py_DECREF(v); Py_DECREF(u); if (err == 0) continue; break; case DELETE_ATTR: w = GETITEM(names, oparg); v = POP(); err = PyObject_SetAttr(v, w, (PyObject *)NULL); /* del v.w */ Py_DECREF(v); break; case STORE_GLOBAL: w = GETITEM(names, oparg); v = POP(); err = PyDict_SetItem(f->f_globals, w, v); Py_DECREF(v); if (err == 0) continue; break; case DELETE_GLOBAL: w = GETITEM(names, oparg); if ((err = PyDict_DelItem(f->f_globals, w)) != 0) format_exc_check_arg( PyExc_NameError, GLOBAL_NAME_ERROR_MSG, w); break; case LOAD_NAME: w = GETITEM(names, oparg); if ((v = f->f_locals) == NULL) { PyErr_Format(PyExc_SystemError, "no locals when loading %s", PyObject_REPR(w)); break; } if (PyDict_CheckExact(v)) { x = PyDict_GetItem(v, w); Py_XINCREF(x); } else { x = PyObject_GetItem(v, w); if (x == NULL && PyErr_Occurred()) { if (!PyErr_ExceptionMatches(PyExc_KeyError)) break; PyErr_Clear(); } } if (x == NULL) { x = PyDict_GetItem(f->f_globals, w); if (x == NULL) { x = PyDict_GetItem(f->f_builtins, w); if (x == NULL) { format_exc_check_arg( PyExc_NameError, NAME_ERROR_MSG ,w); break; } } Py_INCREF(x); } PUSH(x); continue; case LOAD_GLOBAL: w = GETITEM(names, oparg); if (PyString_CheckExact(w)) { /* Inline the PyDict_GetItem() calls. WARNING: this is an extreme speed hack. Do not try this at home. */ long hash = ((PyStringObject *)w)->ob_shash; if (hash != -1) { PyDictObject *d; PyDictEntry *e; d = (PyDictObject *)(f->f_globals); e = d->ma_lookup(d, w, hash); if (e == NULL) { x = NULL; break; } x = e->me_value; if (x != NULL) { Py_INCREF(x); PUSH(x); continue; } d = (PyDictObject *)(f->f_builtins); e = d->ma_lookup(d, w, hash); if (e == NULL) { x = NULL; break; } x = e->me_value; if (x != NULL) { Py_INCREF(x); PUSH(x); continue; } goto load_global_error; } } /* This is the un-inlined version of the code above */ x = PyDict_GetItem(f->f_globals, w); if (x == NULL) { x = PyDict_GetItem(f->f_builtins, w); if (x == NULL) { load_global_error: format_exc_check_arg( PyExc_NameError, GLOBAL_NAME_ERROR_MSG, w); break; } } Py_INCREF(x); PUSH(x); continue; case DELETE_FAST: x = GETLOCAL(oparg); if (x != NULL) { SETLOCAL(oparg, NULL); continue; } format_exc_check_arg( PyExc_UnboundLocalError, UNBOUNDLOCAL_ERROR_MSG, PyTuple_GetItem(co->co_varnames, oparg) ); break; case LOAD_CLOSURE: x = freevars[oparg]; Py_INCREF(x); PUSH(x); if (x != NULL) continue; break; case LOAD_DEREF: x = freevars[oparg]; w = PyCell_Get(x); if (w != NULL) { PUSH(w); continue; } err = -1; /* Don't stomp existing exception */ if (PyErr_Occurred()) break; if (oparg < PyTuple_GET_SIZE(co->co_cellvars)) { v = PyTuple_GET_ITEM(co->co_cellvars, oparg); format_exc_check_arg( PyExc_UnboundLocalError, UNBOUNDLOCAL_ERROR_MSG, v); } else { v = PyTuple_GET_ITEM( co->co_freevars, oparg - PyTuple_GET_SIZE(co->co_cellvars)); format_exc_check_arg( PyExc_NameError, UNBOUNDFREE_ERROR_MSG, v); } break; case STORE_DEREF: w = POP(); x = freevars[oparg]; PyCell_Set(x, w); Py_DECREF(w); continue; case BUILD_TUPLE: x = PyTuple_New(oparg); if (x != NULL) { for (; --oparg >= 0;) { w = POP(); PyTuple_SET_ITEM(x, oparg, w); } PUSH(x); continue; } break; case BUILD_LIST: x = PyList_New(oparg); if (x != NULL) { for (; --oparg >= 0;) { w = POP(); PyList_SET_ITEM(x, oparg, w); } PUSH(x); continue; } break; case BUILD_MAP: x = PyDict_New(); PUSH(x); if (x != NULL) continue; break; case LOAD_ATTR: w = GETITEM(names, oparg); v = TOP(); x = PyObject_GetAttr(v, w); Py_DECREF(v); SET_TOP(x); if (x != NULL) continue; break; case COMPARE_OP: w = POP(); v = TOP(); if (PyInt_CheckExact(w) && PyInt_CheckExact(v)) { /* INLINE: cmp(int, int) */ register long a, b; register int res; a = PyInt_AS_LONG(v); b = PyInt_AS_LONG(w); switch (oparg) { case PyCmp_LT: res = a < b; break; case PyCmp_LE: res = a <= b; break; case PyCmp_EQ: res = a == b; break; case PyCmp_NE: res = a != b; break; case PyCmp_GT: res = a > b; break; case PyCmp_GE: res = a >= b; break; case PyCmp_IS: res = v == w; break; case PyCmp_IS_NOT: res = v != w; break; default: goto slow_compare; } x = res ? Py_True : Py_False; Py_INCREF(x); } else { slow_compare: x = cmp_outcome(oparg, v, w); } Py_DECREF(v); Py_DECREF(w); SET_TOP(x); if (x == NULL) break; PREDICT(JUMP_IF_FALSE); PREDICT(JUMP_IF_TRUE); continue; case IMPORT_NAME: w = GETITEM(names, oparg); x = PyDict_GetItemString(f->f_builtins, "__import__"); if (x == NULL) { PyErr_SetString(PyExc_ImportError, "__import__ not found"); break; } v = POP(); u = TOP(); if (PyInt_AsLong(u) != -1 || PyErr_Occurred()) w = PyTuple_Pack(5, w, f->f_globals, f->f_locals == NULL ? Py_None : f->f_locals, v, u); else w = PyTuple_Pack(4, w, f->f_globals, f->f_locals == NULL ? Py_None : f->f_locals, v); Py_DECREF(v); Py_DECREF(u); if (w == NULL) { u = POP(); x = NULL; break; } READ_TIMESTAMP(intr0); x = PyEval_CallObject(x, w); READ_TIMESTAMP(intr1); Py_DECREF(w); SET_TOP(x); if (x != NULL) continue; break; case IMPORT_STAR: v = POP(); PyFrame_FastToLocals(f); if ((x = f->f_locals) == NULL) { PyErr_SetString(PyExc_SystemError, "no locals found during 'import *'"); break; } READ_TIMESTAMP(intr0); err = import_all_from(x, v); READ_TIMESTAMP(intr1); PyFrame_LocalsToFast(f, 0); Py_DECREF(v); if (err == 0) continue; break; case IMPORT_FROM: w = GETITEM(names, oparg); v = TOP(); READ_TIMESTAMP(intr0); x = import_from(v, w); READ_TIMESTAMP(intr1); PUSH(x); if (x != NULL) continue; break; case JUMP_FORWARD: JUMPBY(oparg); goto fast_next_opcode; PREDICTED_WITH_ARG(JUMP_IF_FALSE); case JUMP_IF_FALSE: w = TOP(); if (w == Py_True) { PREDICT(POP_TOP); goto fast_next_opcode; } if (w == Py_False) { JUMPBY(oparg); goto fast_next_opcode; } err = PyObject_IsTrue(w); if (err > 0) err = 0; else if (err == 0) JUMPBY(oparg); else break; continue; PREDICTED_WITH_ARG(JUMP_IF_TRUE); case JUMP_IF_TRUE: w = TOP(); if (w == Py_False) { PREDICT(POP_TOP); goto fast_next_opcode; } if (w == Py_True) { JUMPBY(oparg); goto fast_next_opcode; } err = PyObject_IsTrue(w); if (err > 0) { err = 0; JUMPBY(oparg); } else if (err == 0) ; else break; continue; PREDICTED_WITH_ARG(JUMP_ABSOLUTE); case JUMP_ABSOLUTE: JUMPTO(oparg); continue; case GET_ITER: /* before: [obj]; after [getiter(obj)] */ v = TOP(); x = PyObject_GetIter(v); Py_DECREF(v); if (x != NULL) { SET_TOP(x); PREDICT(FOR_ITER); continue; } STACKADJ(-1); break; PREDICTED_WITH_ARG(FOR_ITER); case FOR_ITER: /* before: [iter]; after: [iter, iter()] *or* [] */ v = TOP(); x = (*v->ob_type->tp_iternext)(v); if (x != NULL) { PUSH(x); PREDICT(STORE_FAST); PREDICT(UNPACK_SEQUENCE); continue; } if (PyErr_Occurred()) { if (!PyErr_ExceptionMatches(PyExc_StopIteration)) break; PyErr_Clear(); } /* iterator ended normally */ x = v = POP(); Py_DECREF(v); JUMPBY(oparg); continue; case BREAK_LOOP: why = WHY_BREAK; goto fast_block_end; case CONTINUE_LOOP: retval = PyInt_FromLong(oparg); if (!retval) { x = NULL; break; } why = WHY_CONTINUE; goto fast_block_end; case SETUP_LOOP: case SETUP_EXCEPT: case SETUP_FINALLY: /* NOTE: If you add any new block-setup opcodes that are not try/except/finally handlers, you may need to update the PyGen_NeedsFinalizing() function. */ PyFrame_BlockSetup(f, opcode, INSTR_OFFSET() + oparg, STACK_LEVEL()); continue; case WITH_CLEANUP: { /* TOP is the context.__exit__ bound method. Below that are 1-3 values indicating how/why we entered the finally clause: - SECOND = None - (SECOND, THIRD) = (WHY_{RETURN,CONTINUE}), retval - SECOND = WHY_*; no retval below it - (SECOND, THIRD, FOURTH) = exc_info() In the last case, we must call TOP(SECOND, THIRD, FOURTH) otherwise we must call TOP(None, None, None) In addition, if the stack represents an exception, *and* the function call returns a 'true' value, we "zap" this information, to prevent END_FINALLY from re-raising the exception. (But non-local gotos should still be resumed.) */ x = TOP(); u = SECOND(); if (PyInt_Check(u) || u == Py_None) { u = v = w = Py_None; } else { v = THIRD(); w = FOURTH(); } /* XXX Not the fastest way to call it... */ x = PyObject_CallFunctionObjArgs(x, u, v, w, NULL); if (x == NULL) break; /* Go to error exit */ if (u != Py_None && PyObject_IsTrue(x)) { /* There was an exception and a true return */ Py_DECREF(x); x = TOP(); /* Again */ STACKADJ(-3); Py_INCREF(Py_None); SET_TOP(Py_None); Py_DECREF(x); Py_DECREF(u); Py_DECREF(v); Py_DECREF(w); } else { /* Let END_FINALLY do its thing */ Py_DECREF(x); x = POP(); Py_DECREF(x); } break; } case CALL_FUNCTION: { PyObject **sp; PCALL(PCALL_ALL); sp = stack_pointer; #ifdef WITH_TSC x = call_function(&sp, oparg, &intr0, &intr1); #else x = call_function(&sp, oparg); #endif stack_pointer = sp; PUSH(x); if (x != NULL) continue; break; } case CALL_FUNCTION_VAR: case CALL_FUNCTION_KW: case CALL_FUNCTION_VAR_KW: { int na = oparg & 0xff; int nk = (oparg>>8) & 0xff; int flags = (opcode - CALL_FUNCTION) & 3; int n = na + 2 * nk; PyObject **pfunc, *func, **sp; PCALL(PCALL_ALL); if (flags & CALL_FLAG_VAR) n++; if (flags & CALL_FLAG_KW) n++; pfunc = stack_pointer - n - 1; func = *pfunc; if (PyMethod_Check(func) && PyMethod_GET_SELF(func) != NULL) { PyObject *self = PyMethod_GET_SELF(func); Py_INCREF(self); func = PyMethod_GET_FUNCTION(func); Py_INCREF(func); Py_DECREF(*pfunc); *pfunc = self; na++; n++; } else Py_INCREF(func); sp = stack_pointer; READ_TIMESTAMP(intr0); x = ext_do_call(func, &sp, flags, na, nk); READ_TIMESTAMP(intr1); stack_pointer = sp; Py_DECREF(func); while (stack_pointer > pfunc) { w = POP(); Py_DECREF(w); } PUSH(x); if (x != NULL) continue; break; } case MAKE_FUNCTION: v = POP(); /* code object */ x = PyFunction_New(v, f->f_globals); Py_DECREF(v); /* XXX Maybe this should be a separate opcode? */ if (x != NULL && oparg > 0) { v = PyTuple_New(oparg); if (v == NULL) { Py_DECREF(x); x = NULL; break; } while (--oparg >= 0) { w = POP(); PyTuple_SET_ITEM(v, oparg, w); } err = PyFunction_SetDefaults(x, v); Py_DECREF(v); } PUSH(x); break; case MAKE_CLOSURE: { v = POP(); /* code object */ x = PyFunction_New(v, f->f_globals); Py_DECREF(v); if (x != NULL) { v = POP(); err = PyFunction_SetClosure(x, v); Py_DECREF(v); } if (x != NULL && oparg > 0) { v = PyTuple_New(oparg); if (v == NULL) { Py_DECREF(x); x = NULL; break; } while (--oparg >= 0) { w = POP(); PyTuple_SET_ITEM(v, oparg, w); } err = PyFunction_SetDefaults(x, v); Py_DECREF(v); } PUSH(x); break; } case BUILD_SLICE: if (oparg == 3) w = POP(); else w = NULL; v = POP(); u = TOP(); x = PySlice_New(u, v, w); Py_DECREF(u); Py_DECREF(v); Py_XDECREF(w); SET_TOP(x); if (x != NULL) continue; break; case EXTENDED_ARG: opcode = NEXTOP(); oparg = oparg<<16 | NEXTARG(); goto dispatch_opcode; default: fprintf(stderr, "XXX lineno: %d, opcode: %d\n", PyCode_Addr2Line(f->f_code, f->f_lasti), opcode); PyErr_SetString(PyExc_SystemError, "unknown opcode"); why = WHY_EXCEPTION; break; #ifdef CASE_TOO_BIG } #endif } /* switch */ on_error: READ_TIMESTAMP(inst1); /* Quickly continue if no error occurred */ if (why == WHY_NOT) { if (err == 0 && x != NULL) { #ifdef CHECKEXC /* This check is expensive! */ if (PyErr_Occurred()) fprintf(stderr, "XXX undetected error\n"); else { #endif READ_TIMESTAMP(loop1); continue; /* Normal, fast path */ #ifdef CHECKEXC } #endif } why = WHY_EXCEPTION; x = Py_None; err = 0; } /* Double-check exception status */ if (why == WHY_EXCEPTION || why == WHY_RERAISE) { if (!PyErr_Occurred()) { PyErr_SetString(PyExc_SystemError, "error return without exception set"); why = WHY_EXCEPTION; } } #ifdef CHECKEXC else { /* This check is expensive! */ if (PyErr_Occurred()) { char buf[1024]; sprintf(buf, "Stack unwind with exception " "set and why=%d", why); Py_FatalError(buf); } } #endif /* Log traceback info if this is a real exception */ if (why == WHY_EXCEPTION) { PyTraceBack_Here(f); if (tstate->c_tracefunc != NULL) call_exc_trace(tstate->c_tracefunc, tstate->c_traceobj, f); } /* For the rest, treat WHY_RERAISE as WHY_EXCEPTION */ if (why == WHY_RERAISE) why = WHY_EXCEPTION; /* Unwind stacks if a (pseudo) exception occurred */ fast_block_end: while (why != WHY_NOT && f->f_iblock > 0) { PyTryBlock *b = PyFrame_BlockPop(f); assert(why != WHY_YIELD); if (b->b_type == SETUP_LOOP && why == WHY_CONTINUE) { /* For a continue inside a try block, don't pop the block for the loop. */ PyFrame_BlockSetup(f, b->b_type, b->b_handler, b->b_level); why = WHY_NOT; JUMPTO(PyInt_AS_LONG(retval)); Py_DECREF(retval); break; } while (STACK_LEVEL() > b->b_level) { v = POP(); Py_XDECREF(v); } if (b->b_type == SETUP_LOOP && why == WHY_BREAK) { why = WHY_NOT; JUMPTO(b->b_handler); break; } if (b->b_type == SETUP_FINALLY || (b->b_type == SETUP_EXCEPT && why == WHY_EXCEPTION)) { if (why == WHY_EXCEPTION) { PyObject *exc, *val, *tb; PyErr_Fetch(&exc, &val, &tb); if (val == NULL) { val = Py_None; Py_INCREF(val); } /* Make the raw exception data available to the handler, so a program can emulate the Python main loop. Don't do this for 'finally'. */ if (b->b_type == SETUP_EXCEPT) { PyErr_NormalizeException( &exc, &val, &tb); set_exc_info(tstate, exc, val, tb); } if (tb == NULL) { Py_INCREF(Py_None); PUSH(Py_None); } else PUSH(tb); PUSH(val); PUSH(exc); } else { if (why & (WHY_RETURN | WHY_CONTINUE)) PUSH(retval); v = PyInt_FromLong((long)why); PUSH(v); } why = WHY_NOT; JUMPTO(b->b_handler); break; } } /* unwind stack */ /* End the loop if we still have an error (or return) */ if (why != WHY_NOT) break; READ_TIMESTAMP(loop1); } /* main loop */ assert(why != WHY_YIELD); /* Pop remaining stack entries. */ while (!EMPTY()) { v = POP(); Py_XDECREF(v); } if (why != WHY_RETURN) retval = NULL; fast_yield: if (tstate->use_tracing) { if (tstate->c_tracefunc) { if (why == WHY_RETURN || why == WHY_YIELD) { if (call_trace(tstate->c_tracefunc, tstate->c_traceobj, f, PyTrace_RETURN, retval)) { Py_XDECREF(retval); retval = NULL; why = WHY_EXCEPTION; } } else if (why == WHY_EXCEPTION) { call_trace_protected(tstate->c_tracefunc, tstate->c_traceobj, f, PyTrace_RETURN, NULL); } } if (tstate->c_profilefunc) { if (why == WHY_EXCEPTION) call_trace_protected(tstate->c_profilefunc, tstate->c_profileobj, f, PyTrace_RETURN, NULL); else if (call_trace(tstate->c_profilefunc, tstate->c_profileobj, f, PyTrace_RETURN, retval)) { Py_XDECREF(retval); retval = NULL; why = WHY_EXCEPTION; } } } if (tstate->frame->f_exc_type != NULL) reset_exc_info(tstate); else { assert(tstate->frame->f_exc_value == NULL); assert(tstate->frame->f_exc_traceback == NULL); } /* pop frame */ exit_eval_frame: Py_LeaveRecursiveCall(); tstate->frame = f->f_back; return retval; } /* This is gonna seem *real weird*, but if you put some other code between PyEval_EvalFrame() and PyEval_EvalCodeEx() you will need to adjust the test in the if statements in Misc/gdbinit (pystack and pystackv). */ PyObject * PyEval_EvalCodeEx(PyCodeObject *co, PyObject *globals, PyObject *locals, PyObject **args, int argcount, PyObject **kws, int kwcount, PyObject **defs, int defcount, PyObject *closure) { register PyFrameObject *f; register PyObject *retval = NULL; register PyObject **fastlocals, **freevars; PyThreadState *tstate = PyThreadState_GET(); PyObject *x, *u; if (globals == NULL) { PyErr_SetString(PyExc_SystemError, "PyEval_EvalCodeEx: NULL globals"); return NULL; } assert(tstate != NULL); assert(globals != NULL); f = PyFrame_New(tstate, co, globals, locals); if (f == NULL) return NULL; fastlocals = f->f_localsplus; freevars = f->f_localsplus + co->co_nlocals; if (co->co_argcount > 0 || co->co_flags & (CO_VARARGS | CO_VARKEYWORDS)) { int i; int n = argcount; PyObject *kwdict = NULL; if (co->co_flags & CO_VARKEYWORDS) { kwdict = PyDict_New(); if (kwdict == NULL) goto fail; i = co->co_argcount; if (co->co_flags & CO_VARARGS) i++; SETLOCAL(i, kwdict); } if (argcount > co->co_argcount) { if (!(co->co_flags & CO_VARARGS)) { PyErr_Format(PyExc_TypeError, "%.200s() takes %s %d " "%sargument%s (%d given)", PyString_AsString(co->co_name), defcount ? "at most" : "exactly", co->co_argcount, kwcount ? "non-keyword " : "", co->co_argcount == 1 ? "" : "s", argcount); goto fail; } n = co->co_argcount; } for (i = 0; i < n; i++) { x = args[i]; Py_INCREF(x); SETLOCAL(i, x); } if (co->co_flags & CO_VARARGS) { u = PyTuple_New(argcount - n); if (u == NULL) goto fail; SETLOCAL(co->co_argcount, u); for (i = n; i < argcount; i++) { x = args[i]; Py_INCREF(x); PyTuple_SET_ITEM(u, i-n, x); } } for (i = 0; i < kwcount; i++) { PyObject *keyword = kws[2*i]; PyObject *value = kws[2*i + 1]; int j; if (keyword == NULL || !PyString_Check(keyword)) { PyErr_Format(PyExc_TypeError, "%.200s() keywords must be strings", PyString_AsString(co->co_name)); goto fail; } /* XXX slow -- speed up using dictionary? */ for (j = 0; j < co->co_argcount; j++) { PyObject *nm = PyTuple_GET_ITEM( co->co_varnames, j); int cmp = PyObject_RichCompareBool( keyword, nm, Py_EQ); if (cmp > 0) break; else if (cmp < 0) goto fail; } /* Check errors from Compare */ if (PyErr_Occurred()) goto fail; if (j >= co->co_argcount) { if (kwdict == NULL) { PyErr_Format(PyExc_TypeError, "%.200s() got an unexpected " "keyword argument '%.400s'", PyString_AsString(co->co_name), PyString_AsString(keyword)); goto fail; } PyDict_SetItem(kwdict, keyword, value); } else { if (GETLOCAL(j) != NULL) { PyErr_Format(PyExc_TypeError, "%.200s() got multiple " "values for keyword " "argument '%.400s'", PyString_AsString(co->co_name), PyString_AsString(keyword)); goto fail; } Py_INCREF(value); SETLOCAL(j, value); } } if (argcount < co->co_argcount) { int m = co->co_argcount - defcount; for (i = argcount; i < m; i++) { if (GETLOCAL(i) == NULL) { PyErr_Format(PyExc_TypeError, "%.200s() takes %s %d " "%sargument%s (%d given)", PyString_AsString(co->co_name), ((co->co_flags & CO_VARARGS) || defcount) ? "at least" : "exactly", m, kwcount ? "non-keyword " : "", m == 1 ? "" : "s", i); goto fail; } } if (n > m) i = n - m; else i = 0; for (; i < defcount; i++) { if (GETLOCAL(m+i) == NULL) { PyObject *def = defs[i]; Py_INCREF(def); SETLOCAL(m+i, def); } } } } else { if (argcount > 0 || kwcount > 0) { PyErr_Format(PyExc_TypeError, "%.200s() takes no arguments (%d given)", PyString_AsString(co->co_name), argcount + kwcount); goto fail; } } /* Allocate and initialize storage for cell vars, and copy free vars into frame. This isn't too efficient right now. */ if (PyTuple_GET_SIZE(co->co_cellvars)) { int i, j, nargs, found; char *cellname, *argname; PyObject *c; nargs = co->co_argcount; if (co->co_flags & CO_VARARGS) nargs++; if (co->co_flags & CO_VARKEYWORDS) nargs++; /* Initialize each cell var, taking into account cell vars that are initialized from arguments. Should arrange for the compiler to put cellvars that are arguments at the beginning of the cellvars list so that we can march over it more efficiently? */ for (i = 0; i < PyTuple_GET_SIZE(co->co_cellvars); ++i) { cellname = PyString_AS_STRING( PyTuple_GET_ITEM(co->co_cellvars, i)); found = 0; for (j = 0; j < nargs; j++) { argname = PyString_AS_STRING( PyTuple_GET_ITEM(co->co_varnames, j)); if (strcmp(cellname, argname) == 0) { c = PyCell_New(GETLOCAL(j)); if (c == NULL) goto fail; GETLOCAL(co->co_nlocals + i) = c; found = 1; break; } } if (found == 0) { c = PyCell_New(NULL); if (c == NULL) goto fail; SETLOCAL(co->co_nlocals + i, c); } } } if (PyTuple_GET_SIZE(co->co_freevars)) { int i; for (i = 0; i < PyTuple_GET_SIZE(co->co_freevars); ++i) { PyObject *o = PyTuple_GET_ITEM(closure, i); Py_INCREF(o); freevars[PyTuple_GET_SIZE(co->co_cellvars) + i] = o; } } if (co->co_flags & CO_GENERATOR) { /* Don't need to keep the reference to f_back, it will be set * when the generator is resumed. */ Py_XDECREF(f->f_back); f->f_back = NULL; PCALL(PCALL_GENERATOR); /* Create a new generator that owns the ready to run frame * and return that as the value. */ return PyGen_New(f); } retval = PyEval_EvalFrameEx(f,0); fail: /* Jump here from prelude on failure */ /* decref'ing the frame can cause __del__ methods to get invoked, which can call back into Python. While we're done with the current Python frame (f), the associated C stack is still in use, so recursion_depth must be boosted for the duration. */ assert(tstate != NULL); ++tstate->recursion_depth; Py_DECREF(f); --tstate->recursion_depth; return retval; } /* Implementation notes for set_exc_info() and reset_exc_info(): - Below, 'exc_ZZZ' stands for 'exc_type', 'exc_value' and 'exc_traceback'. These always travel together. - tstate->curexc_ZZZ is the "hot" exception that is set by PyErr_SetString(), cleared by PyErr_Clear(), and so on. - Once an exception is caught by an except clause, it is transferred from tstate->curexc_ZZZ to tstate->exc_ZZZ, from which sys.exc_info() can pick it up. This is the primary task of set_exc_info(). XXX That can't be right: set_exc_info() doesn't look at tstate->curexc_ZZZ. - Now let me explain the complicated dance with frame->f_exc_ZZZ. Long ago, when none of this existed, there were just a few globals: one set corresponding to the "hot" exception, and one set corresponding to sys.exc_ZZZ. (Actually, the latter weren't C globals; they were simply stored as sys.exc_ZZZ. For backwards compatibility, they still are!) The problem was that in code like this: try: "something that may fail" except "some exception": "do something else first" "print the exception from sys.exc_ZZZ." if "do something else first" invoked something that raised and caught an exception, sys.exc_ZZZ were overwritten. That was a frequent cause of subtle bugs. I fixed this by changing the semantics as follows: - Within one frame, sys.exc_ZZZ will hold the last exception caught *in that frame*. - But initially, and as long as no exception is caught in a given frame, sys.exc_ZZZ will hold the last exception caught in the previous frame (or the frame before that, etc.). The first bullet fixed the bug in the above example. The second bullet was for backwards compatibility: it was (and is) common to have a function that is called when an exception is caught, and to have that function access the caught exception via sys.exc_ZZZ. (Example: traceback.print_exc()). At the same time I fixed the problem that sys.exc_ZZZ weren't thread-safe, by introducing sys.exc_info() which gets it from tstate; but that's really a separate improvement. The reset_exc_info() function in ceval.c restores the tstate->exc_ZZZ variables to what they were before the current frame was called. The set_exc_info() function saves them on the frame so that reset_exc_info() can restore them. The invariant is that frame->f_exc_ZZZ is NULL iff the current frame never caught an exception (where "catching" an exception applies only to successful except clauses); and if the current frame ever caught an exception, frame->f_exc_ZZZ is the exception that was stored in tstate->exc_ZZZ at the start of the current frame. */ static void set_exc_info(PyThreadState *tstate, PyObject *type, PyObject *value, PyObject *tb) { PyFrameObject *frame = tstate->frame; PyObject *tmp_type, *tmp_value, *tmp_tb; assert(type != NULL); assert(frame != NULL); if (frame->f_exc_type == NULL) { assert(frame->f_exc_value == NULL); assert(frame->f_exc_traceback == NULL); /* This frame didn't catch an exception before. */ /* Save previous exception of this thread in this frame. */ if (tstate->exc_type == NULL) { /* XXX Why is this set to Py_None? */ Py_INCREF(Py_None); tstate->exc_type = Py_None; } Py_INCREF(tstate->exc_type); Py_XINCREF(tstate->exc_value); Py_XINCREF(tstate->exc_traceback); frame->f_exc_type = tstate->exc_type; frame->f_exc_value = tstate->exc_value; frame->f_exc_traceback = tstate->exc_traceback; } /* Set new exception for this thread. */ tmp_type = tstate->exc_type; tmp_value = tstate->exc_value; tmp_tb = tstate->exc_traceback; Py_INCREF(type); Py_XINCREF(value); Py_XINCREF(tb); tstate->exc_type = type; tstate->exc_value = value; tstate->exc_traceback = tb; Py_XDECREF(tmp_type); Py_XDECREF(tmp_value); Py_XDECREF(tmp_tb); /* For b/w compatibility */ PySys_SetObject("exc_type", type); PySys_SetObject("exc_value", value); PySys_SetObject("exc_traceback", tb); } static void reset_exc_info(PyThreadState *tstate) { PyFrameObject *frame; PyObject *tmp_type, *tmp_value, *tmp_tb; /* It's a precondition that the thread state's frame caught an * exception -- verify in a debug build. */ assert(tstate != NULL); frame = tstate->frame; assert(frame != NULL); assert(frame->f_exc_type != NULL); /* Copy the frame's exception info back to the thread state. */ tmp_type = tstate->exc_type; tmp_value = tstate->exc_value; tmp_tb = tstate->exc_traceback; Py_INCREF(frame->f_exc_type); Py_XINCREF(frame->f_exc_value); Py_XINCREF(frame->f_exc_traceback); tstate->exc_type = frame->f_exc_type; tstate->exc_value = frame->f_exc_value; tstate->exc_traceback = frame->f_exc_traceback; Py_XDECREF(tmp_type); Py_XDECREF(tmp_value); Py_XDECREF(tmp_tb); /* For b/w compatibility */ PySys_SetObject("exc_type", frame->f_exc_type); PySys_SetObject("exc_value", frame->f_exc_value); PySys_SetObject("exc_traceback", frame->f_exc_traceback); /* Clear the frame's exception info. */ tmp_type = frame->f_exc_type; tmp_value = frame->f_exc_value; tmp_tb = frame->f_exc_traceback; frame->f_exc_type = NULL; frame->f_exc_value = NULL; frame->f_exc_traceback = NULL; Py_DECREF(tmp_type); Py_XDECREF(tmp_value); Py_XDECREF(tmp_tb); } /* Logic for the raise statement (too complicated for inlining). This *consumes* a reference count to each of its arguments. */ static enum why_code do_raise(PyObject *type, PyObject *value, PyObject *tb) { if (type == NULL) { /* Reraise */ PyThreadState *tstate = PyThreadState_GET(); type = tstate->exc_type == NULL ? Py_None : tstate->exc_type; value = tstate->exc_value; tb = tstate->exc_traceback; Py_XINCREF(type); Py_XINCREF(value); Py_XINCREF(tb); } /* We support the following forms of raise: raise <class>, <classinstance> raise <class>, <argument tuple> raise <class>, None raise <class>, <argument> raise <classinstance>, None raise <string>, <object> raise <string>, None An omitted second argument is the same as None. In addition, raise <tuple>, <anything> is the same as raising the tuple's first item (and it better have one!); this rule is applied recursively. Finally, an optional third argument can be supplied, which gives the traceback to be substituted (useful when re-raising an exception after examining it). */ /* First, check the traceback argument, replacing None with NULL. */ if (tb == Py_None) { Py_DECREF(tb); tb = NULL; } else if (tb != NULL && !PyTraceBack_Check(tb)) { PyErr_SetString(PyExc_TypeError, "raise: arg 3 must be a traceback or None"); goto raise_error; } /* Next, replace a missing value with None */ if (value == NULL) { value = Py_None; Py_INCREF(value); } /* Next, repeatedly, replace a tuple exception with its first item */ while (PyTuple_Check(type) && PyTuple_Size(type) > 0) { PyObject *tmp = type; type = PyTuple_GET_ITEM(type, 0); Py_INCREF(type); Py_DECREF(tmp); } if (PyString_CheckExact(type)) { /* Raising builtin string is deprecated but still allowed -- * do nothing. Raising an instance of a new-style str * subclass is right out. */ if (PyErr_Warn(PyExc_DeprecationWarning, "raising a string exception is deprecated")) goto raise_error; } else if (PyExceptionClass_Check(type)) PyErr_NormalizeException(&type, &value, &tb); else if (PyExceptionInstance_Check(type)) { /* Raising an instance. The value should be a dummy. */ if (value != Py_None) { PyErr_SetString(PyExc_TypeError, "instance exception may not have a separate value"); goto raise_error; } else { /* Normalize to raise <class>, <instance> */ Py_DECREF(value); value = type; type = PyExceptionInstance_Class(type); Py_INCREF(type); } } else { /* Not something you can raise. You get an exception anyway, just not what you specified :-) */ PyErr_Format(PyExc_TypeError, "exceptions must be classes, instances, or " "strings (deprecated), not %s", type->ob_type->tp_name); goto raise_error; } PyErr_Restore(type, value, tb); if (tb == NULL) return WHY_EXCEPTION; else return WHY_RERAISE; raise_error: Py_XDECREF(value); Py_XDECREF(type); Py_XDECREF(tb); return WHY_EXCEPTION; } /* Iterate v argcnt times and store the results on the stack (via decreasing sp). Return 1 for success, 0 if error. */ static int unpack_iterable(PyObject *v, int argcnt, PyObject **sp) { int i = 0; PyObject *it; /* iter(v) */ PyObject *w; assert(v != NULL); it = PyObject_GetIter(v); if (it == NULL) goto Error; for (; i < argcnt; i++) { w = PyIter_Next(it); if (w == NULL) { /* Iterator done, via error or exhaustion. */ if (!PyErr_Occurred()) { PyErr_Format(PyExc_ValueError, "need more than %d value%s to unpack", i, i == 1 ? "" : "s"); } goto Error; } *--sp = w; } /* We better have exhausted the iterator now. */ w = PyIter_Next(it); if (w == NULL) { if (PyErr_Occurred()) goto Error; Py_DECREF(it); return 1; } Py_DECREF(w); PyErr_SetString(PyExc_ValueError, "too many values to unpack"); /* fall through */ Error: for (; i > 0; i--, sp++) Py_DECREF(*sp); Py_XDECREF(it); return 0; } #ifdef LLTRACE static int prtrace(PyObject *v, char *str) { printf("%s ", str); if (PyObject_Print(v, stdout, 0) != 0) PyErr_Clear(); /* Don't know what else to do */ printf("\n"); return 1; } #endif static void call_exc_trace(Py_tracefunc func, PyObject *self, PyFrameObject *f) { PyObject *type, *value, *traceback, *arg; int err; PyErr_Fetch(&type, &value, &traceback); if (value == NULL) { value = Py_None; Py_INCREF(value); } arg = PyTuple_Pack(3, type, value, traceback); if (arg == NULL) { PyErr_Restore(type, value, traceback); return; } err = call_trace(func, self, f, PyTrace_EXCEPTION, arg); Py_DECREF(arg); if (err == 0) PyErr_Restore(type, value, traceback); else { Py_XDECREF(type); Py_XDECREF(value); Py_XDECREF(traceback); } } static void call_trace_protected(Py_tracefunc func, PyObject *obj, PyFrameObject *frame, int what, PyObject *arg) { PyObject *type, *value, *traceback; int err; PyErr_Fetch(&type, &value, &traceback); err = call_trace(func, obj, frame, what, arg); if (err == 0) PyErr_Restore(type, value, traceback); else { Py_XDECREF(type); Py_XDECREF(value); Py_XDECREF(traceback); } } static int call_trace(Py_tracefunc func, PyObject *obj, PyFrameObject *frame, int what, PyObject *arg) { register PyThreadState *tstate = frame->f_tstate; int result; if (tstate->tracing) return 0; tstate->tracing++; tstate->use_tracing = 0; result = func(obj, frame, what, arg); tstate->use_tracing = ((tstate->c_tracefunc != NULL) || (tstate->c_profilefunc != NULL)); tstate->tracing--; return result; } PyObject * _PyEval_CallTracing(PyObject *func, PyObject *args) { PyFrameObject *frame = PyEval_GetFrame(); PyThreadState *tstate = frame->f_tstate; int save_tracing = tstate->tracing; int save_use_tracing = tstate->use_tracing; PyObject *result; tstate->tracing = 0; tstate->use_tracing = ((tstate->c_tracefunc != NULL) || (tstate->c_profilefunc != NULL)); result = PyObject_Call(func, args, NULL); tstate->tracing = save_tracing; tstate->use_tracing = save_use_tracing; return result; } static int maybe_call_line_trace(Py_tracefunc func, PyObject *obj, PyFrameObject *frame, int *instr_lb, int *instr_ub, int *instr_prev) { int result = 0; /* If the last instruction executed isn't in the current instruction window, reset the window. If the last instruction happens to fall at the start of a line or if it represents a jump backwards, call the trace function. */ if ((frame->f_lasti < *instr_lb || frame->f_lasti >= *instr_ub)) { int line; PyAddrPair bounds; line = PyCode_CheckLineNumber(frame->f_code, frame->f_lasti, &bounds); if (line >= 0) { frame->f_lineno = line; result = call_trace(func, obj, frame, PyTrace_LINE, Py_None); } *instr_lb = bounds.ap_lower; *instr_ub = bounds.ap_upper; } else if (frame->f_lasti <= *instr_prev) { result = call_trace(func, obj, frame, PyTrace_LINE, Py_None); } *instr_prev = frame->f_lasti; return result; } void PyEval_SetProfile(Py_tracefunc func, PyObject *arg) { PyThreadState *tstate = PyThreadState_GET(); PyObject *temp = tstate->c_profileobj; Py_XINCREF(arg); tstate->c_profilefunc = NULL; tstate->c_profileobj = NULL; /* Must make sure that tracing is not ignored if 'temp' is freed */ tstate->use_tracing = tstate->c_tracefunc != NULL; Py_XDECREF(temp); tstate->c_profilefunc = func; tstate->c_profileobj = arg; /* Flag that tracing or profiling is turned on */ tstate->use_tracing = (func != NULL) || (tstate->c_tracefunc != NULL); } void PyEval_SetTrace(Py_tracefunc func, PyObject *arg) { PyThreadState *tstate = PyThreadState_GET(); PyObject *temp = tstate->c_traceobj; Py_XINCREF(arg); tstate->c_tracefunc = NULL; tstate->c_traceobj = NULL; /* Must make sure that profiling is not ignored if 'temp' is freed */ tstate->use_tracing = tstate->c_profilefunc != NULL; Py_XDECREF(temp); tstate->c_tracefunc = func; tstate->c_traceobj = arg; /* Flag that tracing or profiling is turned on */ tstate->use_tracing = ((func != NULL) || (tstate->c_profilefunc != NULL)); } PyObject * PyEval_GetBuiltins(void) { PyFrameObject *current_frame = PyEval_GetFrame(); if (current_frame == NULL) return PyThreadState_GET()->interp->builtins; else return current_frame->f_builtins; } PyObject * PyEval_GetLocals(void) { PyFrameObject *current_frame = PyEval_GetFrame(); if (current_frame == NULL) return NULL; PyFrame_FastToLocals(current_frame); return current_frame->f_locals; } PyObject * PyEval_GetGlobals(void) { PyFrameObject *current_frame = PyEval_GetFrame(); if (current_frame == NULL) return NULL; else return current_frame->f_globals; } PyFrameObject * PyEval_GetFrame(void) { PyThreadState *tstate = PyThreadState_GET(); return _PyThreadState_GetFrame(tstate); } int PyEval_GetRestricted(void) { PyFrameObject *current_frame = PyEval_GetFrame(); return current_frame == NULL ? 0 : PyFrame_IsRestricted(current_frame); } int PyEval_MergeCompilerFlags(PyCompilerFlags *cf) { PyFrameObject *current_frame = PyEval_GetFrame(); int result = cf->cf_flags != 0; if (current_frame != NULL) { const int codeflags = current_frame->f_code->co_flags; const int compilerflags = codeflags & PyCF_MASK; if (compilerflags) { result = 1; cf->cf_flags |= compilerflags; } #if 0 /* future keyword */ if (codeflags & CO_GENERATOR_ALLOWED) { result = 1; cf->cf_flags |= CO_GENERATOR_ALLOWED; } #endif } return result; } int Py_FlushLine(void) { PyObject *f = PySys_GetObject("stdout"); if (f == NULL) return 0; if (!PyFile_SoftSpace(f, 0)) return 0; return PyFile_WriteString("\n", f); } /* External interface to call any callable object. The arg must be a tuple or NULL. */ #undef PyEval_CallObject /* for backward compatibility: export this interface */ PyObject * PyEval_CallObject(PyObject *func, PyObject *arg) { return PyEval_CallObjectWithKeywords(func, arg, (PyObject *)NULL); } #define PyEval_CallObject(func,arg) \ PyEval_CallObjectWithKeywords(func, arg, (PyObject *)NULL) PyObject * PyEval_CallObjectWithKeywords(PyObject *func, PyObject *arg, PyObject *kw) { PyObject *result; if (arg == NULL) { arg = PyTuple_New(0); if (arg == NULL) return NULL; } else if (!PyTuple_Check(arg)) { PyErr_SetString(PyExc_TypeError, "argument list must be a tuple"); return NULL; } else Py_INCREF(arg); if (kw != NULL && !PyDict_Check(kw)) { PyErr_SetString(PyExc_TypeError, "keyword list must be a dictionary"); Py_DECREF(arg); return NULL; } result = PyObject_Call(func, arg, kw); Py_DECREF(arg); return result; } const char * PyEval_GetFuncName(PyObject *func) { if (PyMethod_Check(func)) return PyEval_GetFuncName(PyMethod_GET_FUNCTION(func)); else if (PyFunction_Check(func)) return PyString_AsString(((PyFunctionObject*)func)->func_name); else if (PyCFunction_Check(func)) return ((PyCFunctionObject*)func)->m_ml->ml_name; else if (PyClass_Check(func)) return PyString_AsString(((PyClassObject*)func)->cl_name); else if (PyInstance_Check(func)) { return PyString_AsString( ((PyInstanceObject*)func)->in_class->cl_name); } else { return func->ob_type->tp_name; } } const char * PyEval_GetFuncDesc(PyObject *func) { if (PyMethod_Check(func)) return "()"; else if (PyFunction_Check(func)) return "()"; else if (PyCFunction_Check(func)) return "()"; else if (PyClass_Check(func)) return " constructor"; else if (PyInstance_Check(func)) { return " instance"; } else { return " object"; } } static void err_args(PyObject *func, int flags, int nargs) { if (flags & METH_NOARGS) PyErr_Format(PyExc_TypeError, "%.200s() takes no arguments (%d given)", ((PyCFunctionObject *)func)->m_ml->ml_name, nargs); else PyErr_Format(PyExc_TypeError, "%.200s() takes exactly one argument (%d given)", ((PyCFunctionObject *)func)->m_ml->ml_name, nargs); } #define C_TRACE(x, call) \ if (tstate->use_tracing && tstate->c_profilefunc) { \ if (call_trace(tstate->c_profilefunc, \ tstate->c_profileobj, \ tstate->frame, PyTrace_C_CALL, \ func)) { \ x = NULL; \ } \ else { \ x = call; \ if (tstate->c_profilefunc != NULL) { \ if (x == NULL) { \ call_trace_protected(tstate->c_profilefunc, \ tstate->c_profileobj, \ tstate->frame, PyTrace_C_EXCEPTION, \ func); \ /* XXX should pass (type, value, tb) */ \ } else { \ if (call_trace(tstate->c_profilefunc, \ tstate->c_profileobj, \ tstate->frame, PyTrace_C_RETURN, \ func)) { \ Py_DECREF(x); \ x = NULL; \ } \ } \ } \ } \ } else { \ x = call; \ } static PyObject * call_function(PyObject ***pp_stack, int oparg #ifdef WITH_TSC , uint64* pintr0, uint64* pintr1 #endif ) { int na = oparg & 0xff; int nk = (oparg>>8) & 0xff; int n = na + 2 * nk; PyObject **pfunc = (*pp_stack) - n - 1; PyObject *func = *pfunc; PyObject *x, *w; /* Always dispatch PyCFunction first, because these are presumed to be the most frequent callable object. */ if (PyCFunction_Check(func) && nk == 0) { int flags = PyCFunction_GET_FLAGS(func); PyThreadState *tstate = PyThreadState_GET(); PCALL(PCALL_CFUNCTION); if (flags & (METH_NOARGS | METH_O)) { PyCFunction meth = PyCFunction_GET_FUNCTION(func); PyObject *self = PyCFunction_GET_SELF(func); if (flags & METH_NOARGS && na == 0) { C_TRACE(x, (*meth)(self,NULL)); } else if (flags & METH_O && na == 1) { PyObject *arg = EXT_POP(*pp_stack); C_TRACE(x, (*meth)(self,arg)); Py_DECREF(arg); } else { err_args(func, flags, na); x = NULL; } } else { PyObject *callargs; callargs = load_args(pp_stack, na); READ_TIMESTAMP(*pintr0); C_TRACE(x, PyCFunction_Call(func,callargs,NULL)); READ_TIMESTAMP(*pintr1); Py_XDECREF(callargs); } } else { if (PyMethod_Check(func) && PyMethod_GET_SELF(func) != NULL) { /* optimize access to bound methods */ PyObject *self = PyMethod_GET_SELF(func); PCALL(PCALL_METHOD); PCALL(PCALL_BOUND_METHOD); Py_INCREF(self); func = PyMethod_GET_FUNCTION(func); Py_INCREF(func); Py_DECREF(*pfunc); *pfunc = self; na++; n++; } else Py_INCREF(func); READ_TIMESTAMP(*pintr0); if (PyFunction_Check(func)) x = fast_function(func, pp_stack, n, na, nk); else x = do_call(func, pp_stack, na, nk); READ_TIMESTAMP(*pintr1); Py_DECREF(func); } /* Clear the stack of the function object. Also removes the arguments in case they weren't consumed already (fast_function() and err_args() leave them on the stack). */ while ((*pp_stack) > pfunc) { w = EXT_POP(*pp_stack); Py_DECREF(w); PCALL(PCALL_POP); } return x; } /* The fast_function() function optimize calls for which no argument tuple is necessary; the objects are passed directly from the stack. For the simplest case -- a function that takes only positional arguments and is called with only positional arguments -- it inlines the most primitive frame setup code from PyEval_EvalCodeEx(), which vastly reduces the checks that must be done before evaluating the frame. */ static PyObject * fast_function(PyObject *func, PyObject ***pp_stack, int n, int na, int nk) { PyCodeObject *co = (PyCodeObject *)PyFunction_GET_CODE(func); PyObject *globals = PyFunction_GET_GLOBALS(func); PyObject *argdefs = PyFunction_GET_DEFAULTS(func); PyObject **d = NULL; int nd = 0; PCALL(PCALL_FUNCTION); PCALL(PCALL_FAST_FUNCTION); if (argdefs == NULL && co->co_argcount == n && nk==0 && co->co_flags == (CO_OPTIMIZED | CO_NEWLOCALS | CO_NOFREE)) { PyFrameObject *f; PyObject *retval = NULL; PyThreadState *tstate = PyThreadState_GET(); PyObject **fastlocals, **stack; int i; PCALL(PCALL_FASTER_FUNCTION); assert(globals != NULL); /* XXX Perhaps we should create a specialized PyFrame_New() that doesn't take locals, but does take builtins without sanity checking them. */ assert(tstate != NULL); f = PyFrame_New(tstate, co, globals, NULL); if (f == NULL) return NULL; fastlocals = f->f_localsplus; stack = (*pp_stack) - n; for (i = 0; i < n; i++) { Py_INCREF(*stack); fastlocals[i] = *stack++; } retval = PyEval_EvalFrameEx(f,0); ++tstate->recursion_depth; Py_DECREF(f); --tstate->recursion_depth; return retval; } if (argdefs != NULL) { d = &PyTuple_GET_ITEM(argdefs, 0); nd = ((PyTupleObject *)argdefs)->ob_size; } return PyEval_EvalCodeEx(co, globals, (PyObject *)NULL, (*pp_stack)-n, na, (*pp_stack)-2*nk, nk, d, nd, PyFunction_GET_CLOSURE(func)); } static PyObject * update_keyword_args(PyObject *orig_kwdict, int nk, PyObject ***pp_stack, PyObject *func) { PyObject *kwdict = NULL; if (orig_kwdict == NULL) kwdict = PyDict_New(); else { kwdict = PyDict_Copy(orig_kwdict); Py_DECREF(orig_kwdict); } if (kwdict == NULL) return NULL; while (--nk >= 0) { int err; PyObject *value = EXT_POP(*pp_stack); PyObject *key = EXT_POP(*pp_stack); if (PyDict_GetItem(kwdict, key) != NULL) { PyErr_Format(PyExc_TypeError, "%.200s%s got multiple values " "for keyword argument '%.200s'", PyEval_GetFuncName(func), PyEval_GetFuncDesc(func), PyString_AsString(key)); Py_DECREF(key); Py_DECREF(value); Py_DECREF(kwdict); return NULL; } err = PyDict_SetItem(kwdict, key, value); Py_DECREF(key); Py_DECREF(value); if (err) { Py_DECREF(kwdict); return NULL; } } return kwdict; } static PyObject * update_star_args(int nstack, int nstar, PyObject *stararg, PyObject ***pp_stack) { PyObject *callargs, *w; callargs = PyTuple_New(nstack + nstar); if (callargs == NULL) { return NULL; } if (nstar) { int i; for (i = 0; i < nstar; i++) { PyObject *a = PyTuple_GET_ITEM(stararg, i); Py_INCREF(a); PyTuple_SET_ITEM(callargs, nstack + i, a); } } while (--nstack >= 0) { w = EXT_POP(*pp_stack); PyTuple_SET_ITEM(callargs, nstack, w); } return callargs; } static PyObject * load_args(PyObject ***pp_stack, int na) { PyObject *args = PyTuple_New(na); PyObject *w; if (args == NULL) return NULL; while (--na >= 0) { w = EXT_POP(*pp_stack); PyTuple_SET_ITEM(args, na, w); } return args; } static PyObject * do_call(PyObject *func, PyObject ***pp_stack, int na, int nk) { PyObject *callargs = NULL; PyObject *kwdict = NULL; PyObject *result = NULL; if (nk > 0) { kwdict = update_keyword_args(NULL, nk, pp_stack, func); if (kwdict == NULL) goto call_fail; } callargs = load_args(pp_stack, na); if (callargs == NULL) goto call_fail; #ifdef CALL_PROFILE /* At this point, we have to look at the type of func to update the call stats properly. Do it here so as to avoid exposing the call stats machinery outside ceval.c */ if (PyFunction_Check(func)) PCALL(PCALL_FUNCTION); else if (PyMethod_Check(func)) PCALL(PCALL_METHOD); else if (PyType_Check(func)) PCALL(PCALL_TYPE); else PCALL(PCALL_OTHER); #endif result = PyObject_Call(func, callargs, kwdict); call_fail: Py_XDECREF(callargs); Py_XDECREF(kwdict); return result; } static PyObject * ext_do_call(PyObject *func, PyObject ***pp_stack, int flags, int na, int nk) { int nstar = 0; PyObject *callargs = NULL; PyObject *stararg = NULL; PyObject *kwdict = NULL; PyObject *result = NULL; if (flags & CALL_FLAG_KW) { kwdict = EXT_POP(*pp_stack); if (!(kwdict && PyDict_Check(kwdict))) { PyErr_Format(PyExc_TypeError, "%s%s argument after ** " "must be a dictionary", PyEval_GetFuncName(func), PyEval_GetFuncDesc(func)); goto ext_call_fail; } } if (flags & CALL_FLAG_VAR) { stararg = EXT_POP(*pp_stack); if (!PyTuple_Check(stararg)) { PyObject *t = NULL; t = PySequence_Tuple(stararg); if (t == NULL) { if (PyErr_ExceptionMatches(PyExc_TypeError)) { PyErr_Format(PyExc_TypeError, "%s%s argument after * " "must be a sequence", PyEval_GetFuncName(func), PyEval_GetFuncDesc(func)); } goto ext_call_fail; } Py_DECREF(stararg); stararg = t; } nstar = PyTuple_GET_SIZE(stararg); } if (nk > 0) { kwdict = update_keyword_args(kwdict, nk, pp_stack, func); if (kwdict == NULL) goto ext_call_fail; } callargs = update_star_args(na, nstar, stararg, pp_stack); if (callargs == NULL) goto ext_call_fail; #ifdef CALL_PROFILE /* At this point, we have to look at the type of func to update the call stats properly. Do it here so as to avoid exposing the call stats machinery outside ceval.c */ if (PyFunction_Check(func)) PCALL(PCALL_FUNCTION); else if (PyMethod_Check(func)) PCALL(PCALL_METHOD); else if (PyType_Check(func)) PCALL(PCALL_TYPE); else PCALL(PCALL_OTHER); #endif result = PyObject_Call(func, callargs, kwdict); ext_call_fail: Py_XDECREF(callargs); Py_XDECREF(kwdict); Py_XDECREF(stararg); return result; } /* Extract a slice index from a PyInt or PyLong or an object with the nb_index slot defined, and store in *pi. Silently reduce values larger than PY_SSIZE_T_MAX to PY_SSIZE_T_MAX, and silently boost values less than -PY_SSIZE_T_MAX-1 to -PY_SSIZE_T_MAX-1. Return 0 on error, 1 on success. */ /* Note: If v is NULL, return success without storing into *pi. This is because_PyEval_SliceIndex() is called by apply_slice(), which can be called by the SLICE opcode with v and/or w equal to NULL. */ int _PyEval_SliceIndex(PyObject *v, Py_ssize_t *pi) { if (v != NULL) { Py_ssize_t x; if (PyInt_Check(v)) { /* XXX(nnorwitz): I think PyInt_AS_LONG is correct, however, it looks like it should be AsSsize_t. There should be a comment here explaining why. */ x = PyInt_AS_LONG(v); } else if (PyIndex_Check(v)) { x = PyNumber_AsSsize_t(v, NULL); if (x == -1 && PyErr_Occurred()) return 0; } else { PyErr_SetString(PyExc_TypeError, "slice indices must be integers or " "None or have an __index__ method"); return 0; } *pi = x; } return 1; } #undef ISINDEX #define ISINDEX(x) ((x) == NULL || \ PyInt_Check(x) || PyLong_Check(x) || PyIndex_Check(x)) static PyObject * apply_slice(PyObject *u, PyObject *v, PyObject *w) /* return u[v:w] */ { PyTypeObject *tp = u->ob_type; PySequenceMethods *sq = tp->tp_as_sequence; if (sq && sq->sq_slice && ISINDEX(v) && ISINDEX(w)) { Py_ssize_t ilow = 0, ihigh = PY_SSIZE_T_MAX; if (!_PyEval_SliceIndex(v, &ilow)) return NULL; if (!_PyEval_SliceIndex(w, &ihigh)) return NULL; return PySequence_GetSlice(u, ilow, ihigh); } else { PyObject *slice = PySlice_New(v, w, NULL); if (slice != NULL) { PyObject *res = PyObject_GetItem(u, slice); Py_DECREF(slice); return res; } else return NULL; } } static int assign_slice(PyObject *u, PyObject *v, PyObject *w, PyObject *x) /* u[v:w] = x */ { PyTypeObject *tp = u->ob_type; PySequenceMethods *sq = tp->tp_as_sequence; if (sq && sq->sq_ass_slice && ISINDEX(v) && ISINDEX(w)) { Py_ssize_t ilow = 0, ihigh = PY_SSIZE_T_MAX; if (!_PyEval_SliceIndex(v, &ilow)) return -1; if (!_PyEval_SliceIndex(w, &ihigh)) return -1; if (x == NULL) return PySequence_DelSlice(u, ilow, ihigh); else return PySequence_SetSlice(u, ilow, ihigh, x); } else { PyObject *slice = PySlice_New(v, w, NULL); if (slice != NULL) { int res; if (x != NULL) res = PyObject_SetItem(u, slice, x); else res = PyObject_DelItem(u, slice); Py_DECREF(slice); return res; } else return -1; } } static PyObject * cmp_outcome(int op, register PyObject *v, register PyObject *w) { int res = 0; switch (op) { case PyCmp_IS: res = (v == w); break; case PyCmp_IS_NOT: res = (v != w); break; case PyCmp_IN: res = PySequence_Contains(w, v); if (res < 0) return NULL; break; case PyCmp_NOT_IN: res = PySequence_Contains(w, v); if (res < 0) return NULL; res = !res; break; case PyCmp_EXC_MATCH: res = PyErr_GivenExceptionMatches(v, w); break; default: return PyObject_RichCompare(v, w, op); } v = res ? Py_True : Py_False; Py_INCREF(v); return v; } static PyObject * import_from(PyObject *v, PyObject *name) { PyObject *x; x = PyObject_GetAttr(v, name); if (x == NULL && PyErr_ExceptionMatches(PyExc_AttributeError)) { PyErr_Format(PyExc_ImportError, "cannot import name %.230s", PyString_AsString(name)); } return x; } static int import_all_from(PyObject *locals, PyObject *v) { PyObject *all = PyObject_GetAttrString(v, "__all__"); PyObject *dict, *name, *value; int skip_leading_underscores = 0; int pos, err; if (all == NULL) { if (!PyErr_ExceptionMatches(PyExc_AttributeError)) return -1; /* Unexpected error */ PyErr_Clear(); dict = PyObject_GetAttrString(v, "__dict__"); if (dict == NULL) { if (!PyErr_ExceptionMatches(PyExc_AttributeError)) return -1; PyErr_SetString(PyExc_ImportError, "from-import-* object has no __dict__ and no __all__"); return -1; } all = PyMapping_Keys(dict); Py_DECREF(dict); if (all == NULL) return -1; skip_leading_underscores = 1; } for (pos = 0, err = 0; ; pos++) { name = PySequence_GetItem(all, pos); if (name == NULL) { if (!PyErr_ExceptionMatches(PyExc_IndexError)) err = -1; else PyErr_Clear(); break; } if (skip_leading_underscores && PyString_Check(name) && PyString_AS_STRING(name)[0] == '_') { Py_DECREF(name); continue; } value = PyObject_GetAttr(v, name); if (value == NULL) err = -1; else if (PyDict_CheckExact(locals)) err = PyDict_SetItem(locals, name, value); else err = PyObject_SetItem(locals, name, value); Py_DECREF(name); Py_XDECREF(value); if (err != 0) break; } Py_DECREF(all); return err; } static PyObject * build_class(PyObject *methods, PyObject *bases, PyObject *name) { PyObject *metaclass = NULL, *result, *base; if (PyDict_Check(methods)) metaclass = PyDict_GetItemString(methods, "__metaclass__"); if (metaclass != NULL) Py_INCREF(metaclass); else if (PyTuple_Check(bases) && PyTuple_GET_SIZE(bases) > 0) { base = PyTuple_GET_ITEM(bases, 0); metaclass = PyObject_GetAttrString(base, "__class__"); if (metaclass == NULL) { PyErr_Clear(); metaclass = (PyObject *)base->ob_type; Py_INCREF(metaclass); } } else { PyObject *g = PyEval_GetGlobals(); if (g != NULL && PyDict_Check(g)) metaclass = PyDict_GetItemString(g, "__metaclass__"); if (metaclass == NULL) metaclass = (PyObject *) &PyClass_Type; Py_INCREF(metaclass); } result = PyObject_CallFunctionObjArgs(metaclass, name, bases, methods, NULL); Py_DECREF(metaclass); if (result == NULL && PyErr_ExceptionMatches(PyExc_TypeError)) { /* A type error here likely means that the user passed in a base that was not a class (such the random module instead of the random.random type). Help them out with by augmenting the error message with more information.*/ PyObject *ptype, *pvalue, *ptraceback; PyErr_Fetch(&ptype, &pvalue, &ptraceback); if (PyString_Check(pvalue)) { PyObject *newmsg; newmsg = PyString_FromFormat( "Error when calling the metaclass bases\n %s", PyString_AS_STRING(pvalue)); if (newmsg != NULL) { Py_DECREF(pvalue); pvalue = newmsg; } } PyErr_Restore(ptype, pvalue, ptraceback); } return result; } static int exec_statement(PyFrameObject *f, PyObject *prog, PyObject *globals, PyObject *locals) { int n; PyObject *v; int plain = 0; if (PyTuple_Check(prog) && globals == Py_None && locals == Py_None && ((n = PyTuple_Size(prog)) == 2 || n == 3)) { /* Backward compatibility hack */ globals = PyTuple_GetItem(prog, 1); if (n == 3) locals = PyTuple_GetItem(prog, 2); prog = PyTuple_GetItem(prog, 0); } if (globals == Py_None) { globals = PyEval_GetGlobals(); if (locals == Py_None) { locals = PyEval_GetLocals(); plain = 1; } if (!globals || !locals) { PyErr_SetString(PyExc_SystemError, "globals and locals cannot be NULL"); return -1; } } else if (locals == Py_None) locals = globals; if (!PyString_Check(prog) && !PyUnicode_Check(prog) && !PyCode_Check(prog) && !PyFile_Check(prog)) { PyErr_SetString(PyExc_TypeError, "exec: arg 1 must be a string, file, or code object"); return -1; } if (!PyDict_Check(globals)) { PyErr_SetString(PyExc_TypeError, "exec: arg 2 must be a dictionary or None"); return -1; } if (!PyMapping_Check(locals)) { PyErr_SetString(PyExc_TypeError, "exec: arg 3 must be a mapping or None"); return -1; } if (PyDict_GetItemString(globals, "__builtins__") == NULL) PyDict_SetItemString(globals, "__builtins__", f->f_builtins); if (PyCode_Check(prog)) { if (PyCode_GetNumFree((PyCodeObject *)prog) > 0) { PyErr_SetString(PyExc_TypeError, "code object passed to exec may not contain free variables"); return -1; } v = PyEval_EvalCode((PyCodeObject *) prog, globals, locals); } else if (PyFile_Check(prog)) { FILE *fp = PyFile_AsFile(prog); char *name = PyString_AsString(PyFile_Name(prog)); PyCompilerFlags cf; if (name == NULL) return -1; cf.cf_flags = 0; if (PyEval_MergeCompilerFlags(&cf)) v = PyRun_FileFlags(fp, name, Py_file_input, globals, locals, &cf); else v = PyRun_File(fp, name, Py_file_input, globals, locals); } else { PyObject *tmp = NULL; char *str; PyCompilerFlags cf; cf.cf_flags = 0; #ifdef Py_USING_UNICODE if (PyUnicode_Check(prog)) { tmp = PyUnicode_AsUTF8String(prog); if (tmp == NULL) return -1; prog = tmp; cf.cf_flags |= PyCF_SOURCE_IS_UTF8; } #endif if (PyString_AsStringAndSize(prog, &str, NULL)) return -1; if (PyEval_MergeCompilerFlags(&cf)) v = PyRun_StringFlags(str, Py_file_input, globals, locals, &cf); else v = PyRun_String(str, Py_file_input, globals, locals); Py_XDECREF(tmp); } if (plain) PyFrame_LocalsToFast(f, 0); if (v == NULL) return -1; Py_DECREF(v); return 0; } static void format_exc_check_arg(PyObject *exc, char *format_str, PyObject *obj) { char *obj_str; if (!obj) return; obj_str = PyString_AsString(obj); if (!obj_str) return; PyErr_Format(exc, format_str, obj_str); } static PyObject * string_concatenate(PyObject *v, PyObject *w, PyFrameObject *f, unsigned char *next_instr) { /* This function implements 'variable += expr' when both arguments are strings. */ Py_ssize_t v_len = PyString_GET_SIZE(v); Py_ssize_t w_len = PyString_GET_SIZE(w); Py_ssize_t new_len = v_len + w_len; if (new_len < 0) { PyErr_SetString(PyExc_OverflowError, "strings are too large to concat"); return NULL; } if (v->ob_refcnt == 2) { /* In the common case, there are 2 references to the value * stored in 'variable' when the += is performed: one on the * value stack (in 'v') and one still stored in the 'variable'. * We try to delete the variable now to reduce the refcnt to 1. */ switch (*next_instr) { case STORE_FAST: { int oparg = PEEKARG(); PyObject **fastlocals = f->f_localsplus; if (GETLOCAL(oparg) == v) SETLOCAL(oparg, NULL); break; } case STORE_DEREF: { PyObject **freevars = f->f_localsplus + f->f_code->co_nlocals; PyObject *c = freevars[PEEKARG()]; if (PyCell_GET(c) == v) PyCell_Set(c, NULL); break; } case STORE_NAME: { PyObject *names = f->f_code->co_names; PyObject *name = GETITEM(names, PEEKARG()); PyObject *locals = f->f_locals; if (PyDict_CheckExact(locals) && PyDict_GetItem(locals, name) == v) { if (PyDict_DelItem(locals, name) != 0) { PyErr_Clear(); } } break; } } } if (v->ob_refcnt == 1 && !PyString_CHECK_INTERNED(v)) { /* Now we own the last reference to 'v', so we can resize it * in-place. */ if (_PyString_Resize(&v, new_len) != 0) { /* XXX if _PyString_Resize() fails, 'v' has been * deallocated so it cannot be put back into 'variable'. * The MemoryError is raised when there is no value in * 'variable', which might (very remotely) be a cause * of incompatibilities. */ return NULL; } /* copy 'w' into the newly allocated area of 'v' */ memcpy(PyString_AS_STRING(v) + v_len, PyString_AS_STRING(w), w_len); return v; } else { /* When in-place resizing is not an option. */ PyString_Concat(&v, w); return v; } } #ifdef DYNAMIC_EXECUTION_PROFILE static PyObject * getarray(long a[256]) { int i; PyObject *l = PyList_New(256); if (l == NULL) return NULL; for (i = 0; i < 256; i++) { PyObject *x = PyInt_FromLong(a[i]); if (x == NULL) { Py_DECREF(l); return NULL; } PyList_SetItem(l, i, x); } for (i = 0; i < 256; i++) a[i] = 0; return l; } PyObject * _Py_GetDXProfile(PyObject *self, PyObject *args) { #ifndef DXPAIRS return getarray(dxp); #else int i; PyObject *l = PyList_New(257); if (l == NULL) return NULL; for (i = 0; i < 257; i++) { PyObject *x = getarray(dxpairs[i]); if (x == NULL) { Py_DECREF(l); return NULL; } PyList_SetItem(l, i, x); } return l; #endif } #endif