Re: [patch] MIPS/gcc: Revert removal of DImode shifts for 32-bit targets

[Richard Henderson <rth@redhat.com>]

On Fri, Sep 03, 2004 at 08:05:15AM +0100, Richard Sandiford wrote:
>      However, on some machines, such as the 80386 and the 680x0, truncation
>      only applies to shift operations and not the (real or pretended)
>      bit-field operations.  Define @code{SHIFT_COUNT_TRUNCATED} to be zero on
>      such machines.  Instead, add patterns to the @file{md} file that include
>      the implied truncation of the shift instructions.
> 
> I was deliberately trying to avoid this fuzziness with the new target hook.

Hmm.  I suppose we could pass the shift operation in there; 
ASHIFT, LSHIFT, ZERO_EXTRACT, SIGN_EXTRACT.


r~