Re: [ST-devel] AMD64: stack alignment

[Michael A. <ya...@ya...>]

Thanks for the report.  Googling for "movdqa alignment" turns up some interesting links such as this very informative one:  http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40838.  I see in your example that the stack is 32-byte aligned before the pushq but then is no longer aligned properly for the movdqa.  This seems more like a compiler issue than a state threads issue, since state threads ensures that the stack starts 64-byte aligned.  Have you tried compiler options like -mstackrealign or whatever your compiler supports?

Your patch changes the stack base from being 64-byte aligned to being only 8-byte aligned which seems backwards and could break other code.  I'm afraid I won't adopt your patch into the ST distribution as is -- but of course you are welcome to run with your patched version all you like.  If you can devise a more general, universally safe patch I will reconsider.