[LLVMdev] x86 Frame Pointer with AVX

Eric Christopher echristo at gmail.com
Mon Oct 22 14:49:22 PDT 2012

> In trunk, the frame pointer is always set up when an AVX register is used in
> a function. This is done in case 32-byte spill code is later introduced into
> the function and hence dynamic stack realignment is needed. Needless to say,
> it's a big hammer. This regression seems particularly painful in
> small-to-medium sized routines that are called frequently in some codes.
> Is this issue already known? Is there a plan to fix this regression? If not,
> does anyone have a suggestion on the best way to remedy this issue?

You'd need to change the default stack alignment of the platform to
deal with it effectively.


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