tree 2ba0aa06ad4a98840fcabd6799a49a06c5186cd3
parent d9c4ec91542662f7297591b92ed6c4a452004d2b
author Rhys Perry <pendingchaos02@gmail.com> 1591786075 +0100
committer Marge Bot <eric+marge@anholt.net> 1601294790 +0000

nir/load_store_vectorize: improve vectorization with identical operations

We might have several identical options to vectorize an entry with, but
only one might be vectorizable because of writes interfering.

An example of this is a pattern found in some CTS tests:
a = load(0)
b = load(4)
store(0, a)
store(4, b)
a = load(0)
b = load(4)
store(0, a)
store(4, b)
...

It might have attempted to vectorize the first load(0) with the second
load(4) without attempting the second load(4) when the first fails. This
changes vectorize_entries() to continue even if the first try_vectorize()
failed.

fossil-db (Navi):
Totals from 117 (0.09% of 137413) affected shaders:
SGPRs: 7040 -> 7088 (+0.68%)
CodeSize: 276504 -> 276308 (-0.07%); split: -0.08%, +0.01%
Instrs: 51152 -> 51111 (-0.08%); split: -0.09%, +0.01%

Signed-off-by: Rhys Perry <pendingchaos02@gmail.com>
Reviewed-by: Matt Turner <mattst88@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/5415>