This avoids the silly compiler versions. Some bits are slightly more
complicated, because they have to account for inverted enum values (rather than
a separate invert bit), but this is a LOT friendlier to drivers using the pass
and it makes the pass itself more readable.
The conversion functions in panfrost/panvk will go away momentarily.
Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Reviewed-by: Marek Olšák <marek.olsak@amd.com>
Reviewed-by: Italo Nicola <italonicola@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/24076>
Now that we're working on lowered I/O, passing in the dual source blend colour
via a sideband doesn't make any sense. The primary source blend colours are
implicitly passed in as the sources of store_output intrinsics; likewise, we
should get dual source blend colours from their respective stores. And since
dual colours are only needed by blending, we can delete the stores as we go.
That means nir_lower_blend now provides an all-in-one software lowering of dual
source blending with no driver support needed! It even works for 8 dual-src
render targets, but I don't have a use case for that.
The only tricky bit here is making sure we are robust against different orders
of store_output within the exit block. In particular, if we naively lower
x = ...
primary color = x
y = ...
dual color = y
we end up emitting uses of y before it has been defined, something like
x = ...
primary color = blend(x, y)
y = ...
Instead, we remove dual stores and sink blend stores to the bottom of the block,
so we end up with the correct
x = ...
y = ...
primary color = blend(x, y)
lower_io_to_temporaries ensures that the stores will be in the same (exit)
block, so we don't need to sink further than that ourselves.
Signed-off-by: Alyssa Rosenzweig <alyssa@collabora.com>
Reviewed-by: Faith Ekstrand <faith.ekstrand@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/21426>
This pass was originally developed for Panfrost, where it passes the
relevant dEQP tests. Upstreaming so it can be extended and then shared
with:
* Asahi, for blending
* Zink, for logic ops
* Lavapipe, for advanced blending
Note that using this with MRT in a fragment shader (as non-panfrost
drivers will) has not yet been tested. Logic ops with integer
framebuffers are probably todo. It's been enough for Panfrost, will
suffice for ES2 on Asahi, and provides an upstream base for kusma's work
on advanced blending, so overall the merge is a net benefit.
v2: Remove bogus assert that the format layout is PLAIN. We need to
render R11G11B10, which Mesa reports as layout OTHER. The code is still
correct.
Signed-off-by: Alyssa Rosenzweig <alyssa@collabora.com>
Reviewed-by: Erik Faye-Lund <erik.faye-lund@collabora.com> [v1]
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/10601>
