| msg41280 - (view) |
Author: Armin Rigo (arigo) *  |
Date: 2002-10-01 23:17 |
| Psyco-friendly patch #1 Allow Psyco-like extension modules to quickly plug their own notion of frame call stack into Python, for the use of the interpreter's parts that rely on the call stack for context information. For example, the code that creates a new class implicitely reads the top frame's globals if the class does not explicitely defines a __module__ attribute. With this new hook, Psyco can provide such code with the expected frame object. pystate.h: The PyThreadState structure has a new field added at its end: Py_getframehook getframe; where typedef PyFrameObject *(*Py_getframehook)(PyThreadState *, int); This field points to a function that returns the nth frame object in the call stack. By default, it points to a standard function that starts with tstate->frame and walks their f_back fields, just like the implementation of sys._getframe(). The purpose of this is to allow Psyco to hook another function at this point, in order to lazily emulate the frame objects that correspond to frames executed by Psyco. sysmodule.c: sys_getframe() calls the hook. ceval.c: PyEval_GetFrame() calls the hook. various other places in ceval.c: replaced PyThreadState_Get()->frame with PyEval_GetFrame() so that the hook will be called. pyexpat.c: replaced a PyThreadState_Get()->frame->f_globals with PyEval_GetGlobals(). Note that there are other places using 'frame' and the 'f_back' pointers which have not been changed because they are concerned with actual (classical) bytecode interpretation. The hook is only used in places that are interested in obtaining contextual information (like what the previous frame's globals are), not in places that actually builds frames in which bytecode will be interpreted. Compatibility: third-party extension modules directly reading frame, like Expat before this patch, will exhibit a marginally wrong behavior with Psyco until they are modified to call the hook (or better the "official" interpreter routines that are modified to so do). It does not break anything at all as long as we are not using Psyco. Performance overhead: one more indirect call isn't heavy. More importantly, I don't expect the concerned functions to be used more than occasionally in any code. |
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| msg41281 - (view) |
Author: Michael Hudson (mwh) |
Date: 2002-10-04 10:43 |
| Logged In: YES user_id=6656 I'd be uneasy about a change of this subtlety going into the 2.2 branch. Aren't there other ways you can do this? |
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| msg41282 - (view) |
Author: Armin Rigo (arigo) * |
Date: 2002-10-04 15:46 |
| Logged In: YES user_id=4771 Here is a simpler patch doing only the one thing that I really cannot work around in Psyco (and I've tried, believe me!) : a way to hook my own replacement function for PyEval_GetFrame(). No more sysmodule change. Just a few places here and there with 'PyThreadState_Get()->frame' replaced with 'PyEval_GetFrame()' so that my hook will trigger. Is the new patch clean enough ? If so I'll assign it to Guido for review. |
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| msg41283 - (view) |
Author: Guido van Rossum (gvanrossum) * |
Date: 2002-10-06 20:46 |
| Logged In: YES user_id=6380 I'd like to get this int. 2.2.2. MWH, can you check it in? |
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| msg41284 - (view) |
Author: Michael Hudson (mwh) |
Date: 2002-10-07 09:48 |
| Logged In: YES user_id=6656 OK, checked in as: Include/pystate.h revision 2.18.16.2 Modules/pyexpat.c revision 2.57.6.4 Python/ceval.c revision 2.301.4.8 Python/pystate.c revision 2.20.16.1 |
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| msg41285 - (view) |
Author: Guido van Rossum (gvanrossum) * |
Date: 2002-10-07 12:34 |
| Logged In: YES user_id=6380 Thanks much Michael for the three sets of Psyco checkins in 2.2.2! Armin, I think for Python 2.3 some patches must be different because there's no SET_LINENO opcode. Can you provide updated versions for those? |
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| msg41286 - (view) |
Author: Michael Hudson (mwh) |
Date: 2002-11-08 12:59 |
| Logged In: YES user_id=6656 I got lazy and checked in all the psyco patches at once: Include/pystate.h revision 2.21 Modules/pyexpat.c revision 2.76 Python/ceval.c revision 2.340 Python/pystate.c revision 2.22 |
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