[llvm-commits] [PATCH][Target/PTX] Add address_size directive to PTX backend

[陳韋任]

> >> Perhaps my understanding of the .address_size directive is incomplete, but as far as I know it is just used as a flag for ptxas to make sure all PTX modules in a program assume the same pointer size.  That said, what is the purpose of allowing LLVM to generate 32-bit PTX code but assume 64-bit addresses, and vice versa?  Why not tie the directive directly to the existing 32/64-bit flag instead of allowing user intervention?
> > 
> >  I'll wait for Che-Liang and Dan's comment.
> Yep, Justin's right, it makes more sense to use the 64bit flag to indicate the address size. 

  What you want is removing FeatureAddrSize32/64 from PTX.td to avoid
user intervention, right? PTXAddrSize is assigned accroding to the
32/64-bit flag,

// PTXSubtarget ctor in PTXSubtarget.cpp
PTXAddrSize = is64Bit? PTX_AddrSize_64 : PTX_AddrSize_32;

  My question is where is64Bit will be set? Thanks!

Regards,
chenwj

-- 
Wei-Ren Chen (陳韋任)
Computer Systems Lab, Institute of Information Science,
Academia Sinica, Taiwan (R.O.C.)
Tel:886-2-2788-3799 #1667