Re: [coreboot] Compile error in coreboot-v2: "failed to trunc value: mask ff"

[Corey Osgood]

On Wed, Apr 2, 2008 at 5:12 PM, Stefan Reinauer 
wrote:
> In addition, you could try using "unsigned" instead of "u8"... I think
> romcc is kind of bad at handling different data types and it handles all
> sizes equally (ie. using u8 does not gain you the rest of the register you
> are using)

Thanks, unsigned int/long, u16/u32, and int/long all still produce the same
error (including the auto unsigned char part).

-Corey
> Marc Jones wrote:
> > Cory,
> > I don't know what the error means. Others might know more but I can make
> > some recommendations for you to try.
> > ROMCC problems are usually a stack depth problem. ROMCC is using
> > registers for stack space so every function call uses up registers. The code
> > around this code will have a big effect if this code will work. First try to
> > inline the code (ROMCC might already be doing this). Next, try moving the
> > pci read to after the math so the value doesn't need to be stored before it
> > is used.
> >
> > Marc
> >
> > Corey Osgood wrote:
> > > Working with romcc here, you can drop this block of code into the
> > > auto.c/raminit portion of any board using romcc and reproduce the error (it
> > > compiles fine with CAR, but that's not an option with the c7 cpu, at least
> > > not yet):
> > >
> > > u8 reg8, spd_data;
> > >
> > > reg8 = pci_read_config8(PCI_DEV(0, 0, 3), 0x62);
> > > spd_data = smbus_read_byte(0x50, 30);
> > > spd_data = spd_data / 10;
> > > if(spd_data < 5)
> > >    spd_data = 5;
> > > else if(spd_data > 20)
> > >    spd_data = 20;
> > >
> > > if(spd_data > (reg8 >> 4))
> > > {
> > >   reg8 &= 0xf;
> > >   reg8 |= (spd_data << 4);
> > > }
> > >
> > > The error is confirmed on ubuntu 8.04 alpha/beta/? and debian
> > > unstable, both with gcc 4.2.3, and also gentoo with gcc 4.1.2:
> > >
> > > dst type: auto unsigned char
> > > dst: %edx:%eax
> > > auto.c:35.1: raminit.c:436.33: raminit.c:615.36: auto.c:218.32:
> > > 0x83cbe70 convert    Internal compiler error: failed to trunc value:
> > > mask ff
> > > make[1]: *** [auto.inc] Aborted (core dumped)
> > >
> > > Commenting out either spd_data/10 or the if/else portion gets rid of
> > > the error, it only happens when all of these statements are in. I also have
> > > half a dozen blocks like this which compile fine:
> > >
> > > reg8 = pci_read_config8(ctrl->d0f3, 0x63);
> > >    j = spd_read_byte(ctrl->channel0[i], SPD_tRRD);//ctrl->channel0[0]
> > > = 0x50
> > >    spd_data = ((j >> 2) * 100);
> > >    spd_data |= ((j & 0x3) * 25);
> > >    spd_data = spd_data / (ram_cycle * 100); //ram_cycle in this case =
> > > 10
> > >    if(spd_data < 2)
> > >        spd_data = 2;
> > >    else if(spd_data > 5)
> > >        spd_data = 5;
> > >
> > > if((spd_data - 2) > (reg8 >> 6)) {
> > >        reg8 &= 0x3f;
> > >        reg8 |= (spd_data - 2) << 6;
> > >    }
> > >
> > > It's just that one instance that fails to compile. I've tried moving
> > > it around, changing the variables, changing the types, modifying the math,
> > > etc, etc, and nothing seems to help. Any suggestions?