Thanks Armin! This helps me a lot, I will try this out Regards, Vaibhav
-----Original Message----- From: armin.r...@gmail.com [mailto:armin.r...@gmail.com] On Behalf Of Armin Rigo Sent: Wednesday, October 14, 2015 7:30 PM To: Vaibhav Sood Cc: pypy-dev@python.org Subject: Re: [pypy-dev] PPC stacklet switching code Hi Vaibhav, On Wed, Oct 14, 2015 at 11:26 AM, Vaibhav Sood <vaibhav_s...@persistent.com> wrote: > code to return back to the calling function slp_switch. However in > between the calling function’s stack content is overwritten by the > g_restore_state code (it memcpy’s the stored heap memory data to the > stack) causing the saved LR value to be destroyed and thus returning > from the g_restore_state function (using blr) causes a segfault I would decrement sp around the two calls to the C functions, g_save_state and g_restore_state, to give them their own temporary places to write to without interference. This is similar to how the x86 version gives "rsp" as argument, but then uses CALL, which pushes the return address just below rsp, i.e. out of scope of the saving/restoring. Example: ... mr r3, sp # the 1st argument is the value of sp without the extra space stdu sp, -64(sp) # decrement sp again; 64 should be enough ...call g_save_state... addi sp, sp, 64 # restore sp ... A bientôt, Armin. DISCLAIMER ========== This e-mail may contain privileged and confidential information which is the property of Persistent Systems Ltd. It is intended only for the use of the individual or entity to which it is addressed. If you are not the intended recipient, you are not authorized to read, retain, copy, print, distribute or use this message. If you have received this communication in error, please notify the sender and delete all copies of this message. Persistent Systems Ltd. does not accept any liability for virus infected mails. _______________________________________________ pypy-dev mailing list pypy-dev@python.org https://mail.python.org/mailman/listinfo/pypy-dev
