[llvm] [llvm-exegesis] [AArch64] Add support for Load Instructions in subprocess execution mode (PR #144895)

[Aiden Grossman via llvm-commits]

boomanaiden154 wrote:

> Thus, Can you please shed some light on usage of VAddressSpaceCeiling - 2 * pagesize for ioctl syscall in x86 implementation by you. Similarly, for fd for aux mmap and specific memory address. And, can we expect that logic/pathway arch independent?

We map two pages in at the end of the user-mode virtual address space for the auxiliary memory. I think we use the first page for the actual data we need, and the second page as a stack for setting up vector registers. https://github.com/llvm/llvm-project/blob/7546bd38041612e8b768f4b315e491cd549d608c/llvm/tools/llvm-exegesis/lib/SubprocessMemory.cpp#L114 controls the layout. The setup should be reasonably architecture independent.

https://github.com/llvm/llvm-project/pull/144895