[Mesa-dev] [PATCH 1/2] radeon/llvm: add an intrinsic converting clipvertex to clipdistance

[Vadim Girlin]

On Mon, 2012-12-17 at 07:01 +0400, Vadim Girlin wrote:
> I think the clipvertex emulation via clipdistance is rather a driver's
> job and compiler shouldn't be aware of that, driver should simply emit
> all corresponding DOT's and exports.
> 
> As for the kcache regs, in your patch it looks like you are going to
> hardcode some logic to access another const buffer where clip planes are
> stored, but I don't think we need kcache regs until we implement kcache
> allocation for alu clauses in the backend, and this implies that we need
> instruction scheduler that knows about clauses etc.

By the way, I'm attaching the diagram that explains how kcache works for
const buffer access in ALU clauses, and why you can't simply hardcode
some src_sel values for kcache access in the backend - in such case
you'll also need some way to initialize kcache mapping in the CF_ALU
instruction that starts the ALU clause where you want to access your
constants, but currently backend doesn't know anything about clauses.

Vadim
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