Q: How to do dynamic stack alignment

[Jim Wilson]

Fred Fish wrote:
> Any suggestions for how to implement dynamic stack adjustment or
> pointers to an existing implement would be very helpful.

The spe_64bit_regs_used stuff in rs6000.c is somewhat similar to what 
you are trying to do.

It searches a function for instructions that use SPE registers, and if 
there is one, it sets up the prologue to align the register save area 
and do 64-bit register saves instead of 32-bit register saves.

Jim