nir_lower_blend was written against the OpenGL ES 3.2 specification,
which does not support blending SNORM render targets. The ES spec
says that non-floating point buffers get clamped to [0, 1] before
blending. The story is not so simple: SNORM buffers are blendable in
OpenGL and must clamped to [-1, 1] rather than [0, 1]. Handle this case.
NIR does have the fsat_signed_mali instruction to clamp to [-1, 1], but
it is only implemented in Panfrost, and this pass is in common code.
Open code it instead. Panfrost optimizes the open coded version, so this
is good enough.
Fixes SNORM subtests of Piglit arb_texture_view-rendering-formats.
Signed-off-by: Alyssa Rosenzweig <alyssa@collabora.com>
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/13499>
Make sure the new and old sources have the same number of components,
otherwise the NIR validation pass complains.
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/13060>
SCALED formats are interpreted as floats, but not in the usual [0, 1]
or [-1, 1] range, meaning that the blend lowering logic can't directly
apply to those. Assert that the format being passed is not a scaled
format.
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/13060>
The caller doesn't necessarily want to lower blend operations on all
render targets since some of them might be supported natively (panvk
will be in that case). Let's just skip RTs that have a format set to
PIPE_FORMAT_NONE to allow that.
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/13060>
nir_ssa_for_src() is not supposed to pad the src vector if
dst->num_components > src->num_components. Let's pad things explicitly
with nir_pad_vector().
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/13060>
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>
