[lldb-dev] Host::GetArchitecture and the default target triple

[Zachary Turner]

Ok. So it looks like x86_64h is not currently supported by llvm::Triple.  I
will find out about adding support for it.  If it's possible to get that
into llvm::Triple, I'll post a patch that updates Host::GetArchitecture()
to use it, and then maybe one of you guys can test it in the various
configurations.

Thanks!


On Tue, Aug 19, 2014 at 2:18 PM, <jingham at apple.com> wrote:

> Sorry, I didn't read closely enough.  Greg's answer is actually relevant
> to your question...
>
> Jim
>
> > On Aug 19, 2014, at 2:04 PM, Zachary Turner <zturner at google.com> wrote:
> >
> > In this case though, we're talking about Host::GetArchitecture, which is
> a static function and is supposed to report information about the OS that
> the debugger is running on, and not the target that the debuggee is running
> on.  Does this mean that a single instance of LLDB cannot debug both an app
> running in the simulator, and an app running in darwin?  So you have to
> exit LLDB and start a new instance of LLDB in "simulator mode" or "mac
> mode"?  Or am I misunderstanding?
> >
> >
> > On Tue, Aug 19, 2014 at 1:58 PM, <jingham at apple.com> wrote:
> > Mac OS X is more complex because lldb also supports apps running in the
> iOS simulator on OS X.  Those apps are x86 or x86_64 processes, but their
> OS is "ios", not "darwin".  The platforms and a bunch of other fiddly bits
> rely on getting the OS right as well.
> >
> > Jim
> >
> > > On Aug 19, 2014, at 1:52 PM, Zachary Turner <zturner at google.com>
> wrote:
> > >
> > > Looking over the apple code path for Host::GetArchitecture, I'm a
> little confused about why all this custom logic is needed.  What are the
> situations in which llvm::sys::getDefaultTargetTriple() will return
> something other than what we want?  Specifically, a concrete example might
> help illustrate the problem.
> > >
> > > I understand from the comment that it has something to do with being
> able to run 32 and 64-bit executables in the same operating system.  Isn't
> this the case everywhere?  I can run 32-bit executables on Windows x64 as
> well.  llvm::Triple has a function called get32BitArchVariant() that I
> thought returns a 32-bit triple for this case.  Does this not work for some
> Apple configuration?
> > >
> > > It seems like this logic should be able to be sunk into llvm::Triple
> somehow.  Conceptually speaking, it seems like there should be two cases:
> > >
> > > 64-bit:
> > > host_arch_64 = llvm::Triple::getDefaultTargetTriple()
> > > host_arch_32 =
> llvm::Triple::getDefaultTargetTriple().get32BitArchVariant()
> > >
> > > 32-bit
> > > host_arch_64 = <empty>
> > > host_arch_32 = llvm::Triple::getDefaultTargetTriple()
> > >
> > > Why doesn't this work?
> > > _______________________________________________
> > > lldb-dev mailing list
> > > lldb-dev at cs.uiuc.edu
> > > http://lists.cs.uiuc.edu/mailman/listinfo/lldb-dev
> >
> >
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.llvm.org/pipermail/lldb-dev/attachments/20140819/25807ec6/attachment.html>