Re: [Linux-fbdev-devel] Re: [PATCH]: cfb_imageblit() fix: handle widths not divisible by 8

[Geert U. <ge...@li...>]

On 15 Jan 2003, Antonino Daplas wrote:
> On Wed, 2003-01-15 at 08:26, James Simmons wrote:
> > Applied.
> > 
> > > c. Fix for fast_imageblit() so it always refer to mask tables in 32-bits
> > > which should make it work for 64-bit machines.
> > 
> > Ug. I rather try yo take advantge of using the full 64 bits of data to 
> > pass across the bus. What I was think is treat the 64 bit case as two 32 
> > bit cases. The 64 bit data comes in and we run the data twice at tabs[].
> > 
> Hi James,
> 
> Yes, I was trying to find a way to make fast_imageblit() be fast for all
> machine architectures.  With the patch attached, there's
> fast_imageblit32() and fast_imageblit64().  fast_imageblit32() is
> probably slower than fast_imageblit64 on 64-bit machines and, on the
> other hand, fast_imageblit64() is 20% slower on 32-bit machines, but is
> probably faster on 64-bit and higher machines.  So, the only way I can
> think of doing this on all machine architectures is to have them go
> separate paths.

Can't you merge fast_imageblit32() and fast_imageblit64() a bit more (with some
#ifdef's), and just call the result fast_imageblit()? Then the definition of
FAST_IMAGEBLIT can go away.

u32 is the same as unsigned long if BITS_PER_LONG == 32.

Gr{oetje,eeting}s,

						Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- ge...@li...

In personal conversations with technical people, I call myself a hacker. But
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