On 7/31/23 17:36, Tom Rini wrote:
On Mon, Jul 31, 2023 at 05:27:33PM -0400, Sean Anderson wrote:

Since ARMv5, the clz instruction allows for efficient implementation of
ffs/fls with builtins. Until ARMv7 (with Thumb-2), this instruction is
only available in ARM mode. LTO makes it difficult to force specific
functions to be in ARM mode, as it is effectively a form of very
aggressive inlining. To work around this, fls/ffs are implemented in
assembly for ARMv5 and ARMv6 when compiling U-Boot in Thumb mode.
Overall, this saves around 75 bytes per call.

Signed-off-by: Sean Anderson <sean.ander...@seco.com>

This looks like it's synced from the kernel, what tag?


The builtins are synced from v5.15 and they haven't changed since.

--Sean

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