The existing non-builtin implementation is returning wrong results.
For example, given the value 63 as a uint8_t it returns 38 (should be 6).
The new implementation follows the naive algorithm presented in figure 5-1
in Hacker's Delight section 5-1.
Note that the algorithm in the book is designed for 32 bit numbers, so we
extended it to support 64 bit as well.
Bug: chromium:1056170
Change-Id: I8fed9c449f80b01b8cc93d339529c0e1e0863fc0
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2199345
Reviewed-by: Clemens Backes <clemensb@chromium.org>
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Anton Bikineev <bikineev@chromium.org>
Commit-Queue: Omer Katz <omerkatz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#67801}
cc6dfd5d67