Use udis86 to walk x64 machine code in find_fast_cwd_pointer

[Corinna Vinschen]

On Mar 20 15:03, Corinna Vinschen wrote:
> On Mar 18 22:11, Jeremy Drake via Cygwin-patches wrote:
> > On Tue, 18 Mar 2025, Corinna Vinschen wrote:
> > 
> > > Subdir of winsup/cygwin, probably.  What I'm most curious about is the
> > > size it adds to the DLL.  I wonder if, say, an extra 32K is really
> > > usefully spent, given it only checks a small part of ntdll.dll, and only
> > > once per process tree, too.
> > 
> > I did this with msys-2.0.dll, but it shouldn't matter as a delta.
> > all are stripped msys-2.0.dll size
> > start:
> > 3,246,118 bytes
> > with udis86 vendored, but not called:
> > 3,247,142 bytes
> > with find_fast_cwd_pointer rewritten to use udis86:
> > 3,328,550 bytes
> > 
> > (I know the second one isn't realistic, the linker could exclude unused
> > code, I was just kind of curious)
> > 
> > This is with all the "translate to assembly text, intel or at&t syntax"
> > and "table of strings for opcodes" stuff removed to try to save space,
> > still a net increase of 82,432 bytes.
> 
> The DLL has currently a size of 3 Megs, optimzed, stripped.  82K are
> two more allocation granularity slots, 51 instead of 49, about 2%.

4!  4%.  I said 4%, right?

*facepalm*