On Tue, Aug 15, 2017 at 05:12:39PM -0700, Ori Bernstein wrote:
> On Sat, 22 Jul 2017 02:25:29 -0400
> Todd Mortimer wrote:
>
> > xor [rsp], rsp
> >
> > at the start of each function, and before every RET.
>
> Wouldn't this break with alloca() or C99 VLAs?
> %rbp may work better, if the frame po
On Sat, 22 Jul 2017 02:25:29 -0400
Todd Mortimer wrote:
> xor [rsp], rsp
>
> at the start of each function, and before every RET.
Wouldn't this break with alloca() or C99 VLAs?
%rbp may work better, if the frame pointer is
retained.
--
Ori Bernstein
> Cool stuff. The downside is that this probably kills doing
> backtraces, making debugging stuff hard. Unless this also changes the
> DWARF debugging information to reflect the xor operation. But I'm not
> sure that's possible.
I think it is possible, but some help is probably needed in gdb.
> Date: Sat, 22 Jul 2017 02:25:29 -0400
> From: Todd Mortimer
>
> Hello tech,
>
> I've been working on llvm/clang some lately, and am experimenting with
> the llvm Pass infrastructure. Passes essentially let you perform
> arbitrary transforms on the program at various points in the compilation
>
Hello tech,
I've been working on llvm/clang some lately, and am experimenting with
the llvm Pass infrastructure. Passes essentially let you perform
arbitrary transforms on the program at various points in the compilation
process.
I've attached a patch that defines a machine function pass that add
