Re: [avr-llvm-devel] Windows build

[John M. <ato...@gm...>]

On Tue, Dec 8, 2009 at 7:04 PM, Weddington, Eric
<Eri...@at...>wrote:

>
>
> > -----Original Message-----
> > From: John Myers [mailto:ato...@gm...]
> > Sent: Tuesday, December 08, 2009 6:46 PM
> > To: Weddington, Eric
> > Cc: avr...@li...
> > Subject: Re: [avr-llvm-devel] Windows build
> >
> >
> >
> > The redudant mov is gone now. So it looks like whatever they
> > changed  in the LLVM trunk fixed it.
>
> That's great!
>
> Question: Is the assembler output of llvm supposed to closely match the
> assembler output of avr-gcc? Is that what we're aiming for?
>

Yeah, it's suppose to be an assembly printer for gas / avr-gcc. Some targets
actually produce multiple asm types for different assembler brands.

>
> > C:\_projects_\build_llvm\bin\Debug>llc.exe -O0 -o -
> > -filetype=asm -mcpu=atmega128 reti8.ll
> >         .file   "reti8.ll"
> >
> >         .text
> >         .align  16
> >         .global func
> >         .type   func,@function
> > func:
> > # BB#0:
> >         ldi r24, #1
> >         ret
> >         .size   func, .-func
>
> If so, then we need to drop the .align directive above. This is the
> equivalent from avr-gcc:
>

I'll try to find were the .align directive is printed to remove it. Will it
mess things up if it's there?


>
>        .file   "test.c"
> __SREG__ = 0x3f
> __SP_H__ = 0x3e
> __SP_L__ = 0x3d
> __CCP__  = 0x34
> __tmp_reg__ = 0
> __zero_reg__ = 1
>        .text
> .global func
>        .type   func, @function
> func:
> /* prologue: function */
> /* frame size = 0 */
>        ldi r24,lo8(1)
> /* epilogue start */
>        ret
>        .size   func, .-func
>