[LLVMdev] [llvm-commits] [llvm] r160610 - /llvm/trunk/lib/ExecutionEngine/TargetSelect.cpp

[NAKAMURA Takumi]

Andy,

Yes, it was wrong, as long as RemoteTarget is available for the target.

If you would revert it, please consider then;

  - non-MCJIT stuff
  - Running different environment on the JIT
    e.g.) --build=--host=i686-linux --target=x86_64-linux
  - Host-incapable target on the JIT
    e.g.) --build=--host=x86_64-linux ---target=i686-mingw32

If JIT is unavailable for the default target, tests in
test/ExecutionEngine and unittests/ExecutionEngine/JIT should be
suppressed. My r160610 intended to tweak tests on cross targets (not
to suppress, but to appease).

I wonder if we should honor the triple in Module, though.

Feel free to update, unless breaking tests, thank you.

...Takumi


2012/9/12 Kaylor, Andrew <andrew.kaylor at intel.com>:
> Hi,
>
> I realize that this is an old commit, but I just came across a problem related to this change and was hoping to enquire as to the rationale here.
>
> It is possible to provide a target triple to lli via the '-mtriple' command line option.  However, as a result of the change below, the user specified triple gets ignored in favor of LLVM_HOSTTRIPLE.  This seems wrong.
>
> I recognize that problems can arise if you try to use a target other than the default host triple with JIT or MCJIT.  However, with MCJIT it may be desirable to provide an environment string via the triple to generate MachO or ELF objects on platforms that wouldn't normally use those formats.  In particular, I am working on adding support for generating ELF objects on Windows (because COFF isn't supported by MCJIT).
>
> The change below prevents that.  As such, I would like to revert this change, or at least modify this to pick-up the environment from the module's target triple.
>
> Does that seem reasonable?
>
> -Andy
>
>
> -----Original Message-----
> From: llvm-commits-bounces at cs.uiuc.edu [mailto:llvm-commits-bounces at cs.uiuc.edu] On Behalf Of NAKAMURA Takumi
> Sent: Saturday, July 21, 2012 8:05 PM
> To: llvm-commits at cs.uiuc.edu
> Subject: [llvm-commits] [llvm] r160610 - /llvm/trunk/lib/ExecutionEngine/TargetSelect.cpp
>
> Author: chapuni
> Date: Sat Jul 21 22:04:57 2012
> New Revision: 160610
>
> URL: http://llvm.org/viewvc/llvm-project?rev=160610&view=rev
> Log:
> ExecutionEngine/TargetSelect.cpp: Override default triple as LLVM_HOSTTRIPLE.
>
> In current implementation, JIT should run only on host.
>
> Modified:
>     llvm/trunk/lib/ExecutionEngine/TargetSelect.cpp
>
> Modified: llvm/trunk/lib/ExecutionEngine/TargetSelect.cpp
> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/ExecutionEngine/TargetSelect.cpp?rev=160610&r1=160609&r2=160610&view=diff
> ==============================================================================
> --- llvm/trunk/lib/ExecutionEngine/TargetSelect.cpp (original)
> +++ llvm/trunk/lib/ExecutionEngine/TargetSelect.cpp Sat Jul 21 22:04:57
> +++ 2012
> @@ -26,7 +26,7 @@
>  using namespace llvm;
>
>  TargetMachine *EngineBuilder::selectTarget() {
> -  Triple TT(M->getTargetTriple());
> +  Triple TT(LLVM_HOSTTRIPLE);
>    return selectTarget(TT, MArch, MCPU, MAttrs);  }