This makes the compiler less predictable and should only have a very small
effect on performance.
fossil-db (Vega):
Totals from 2410 (1.79% of 134756) affected shaders:
CodeSize: 6911568 -> 6942840 (+0.45%)
Fixes Horizon Zero Dawn artifacts.
If a shader has:
a = pack_half_2x16(a, 0) //rtne
store(pack_half_2x16(0, b) | a) //rtne
a = unpack_2x16(a).x
It will become:
store(pack_half_2x16(a, b)) //rtz
a = unpack_2x16(pack_half_2x16(a, 0)).x //rtne
So a later shader with "unpack_2x16(load()).x" will use "a" rounded to
zero, while the previous shader will use "a" rounded to the nearest even.
Signed-off-by: Rhys Perry <pendingchaos02@gmail.com>
Reviewed-by: Daniel Schürmann <daniel@schuermann.dev>
Fixes: 2f125908b3 ("radv,aco: lower_pack_half_2x16")
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/14475>
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