This optimizes v_add(c, v_lshlrev(a, b)) to v_mad_u32_u24(b, 1<<a, c)
if 'a' is a constant (less than or equal to 6 to avoid creating
literals) and 'b' known to be a 16-bit or a 24-bit value.
On GFX9+, this is already optimized to v_lshl_add_u32.
No fossils-db changes.
Signed-off-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Reviewed-by: Rhys Perry <pendingchaos02@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/7673>
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