f98e9a2771
Rather than supplying a mask/swizzle to compose with the original, just supply the offset of the allocated register so we can directly offset the mask/swizzle, without resorting to composition. This is simpler, cleaner, and will generalize to non-32-bit. Signed-off-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>