[LLVMdev] Can't bootstrap llvm-gcc-4.0 for x84_64

David Greene dag at cray.com
Wed Oct 10 15:12:28 PDT 2007


On Wednesday 10 October 2007 12:53, Chris Lattner wrote:
> On Mon, 8 Oct 2007, Evan Cheng wrote:
> > I am turning 32-bit add into 32-bit LEA on x86-64 but that's
> > perfectly legal. Both
> > leal (%esi,%edi), %eax
> > leal (%rsi,%rdi), %eax
> > are legal assembly. It's just the former requires a 67H prefix due to
> > the 32-bit address size.
> >
> > This does point to a performance problem in the 3 address conversion
> > code (which I will fix), but it should not cause the assembler to
> > complain.
>
> Thanks for fixing this.  IIRC, some versions of GAS don't support the less
> efficient encoding at all.  In any case, this should be fixed.  Dave, can
> you verify bootstrap works now?

This particular problem is gone (thanks!) but I'm having other troubles.
I'm tracking those down now.

                                                      -Dave



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