[LLVMdev] TableGen !eq() Operator Patch
clattner at apple.com
Tue Jan 5 10:31:32 PST 2010
On Jan 5, 2010, at 9:59 AM, David Greene wrote:
> Attached is a patch to implement an !eq() operator in TableGen. We
> use this
> for the AVX specification to allow the user to control what kind of
> should be used for a particular instruction def. For example, we
> use it for
> reg-mem instructions to let the user choose between a built-in
> generic reg-mem
> pattern, the same pattern that was used for the reg-reg variant of the
> instruction or a custom pattern provided by the user.
> It only operates on strings.
> An alternative to this would be to implement named parameters in
> TableGen but
> that seems like overkill for this case. Named parameters could be
> useful in
> other areas to reduce template complexity but implementing it is non-
> given the widespread assumption in the TableGen sources that template
> parameters exactly match up with template arguments.
I can't say if this is really the best answer for AVX, but
independently of that the patch looks great, please commit.
More information about the llvm-dev