On Mon, 18 Apr 2022 03:48:13 GMT, Quan Anh Mai <d...@openjdk.java.net> wrote:
> Because unsigned cast should operate on unsigned types, the more appropriate > usage is `(src[i] & 0xFF) >>> 3`, with the `&` operation is the cast from > unsigned byte to int. Actually, I fail to understand the intention of your > example, why not use signed shift instead, what does unsigned shift provide > here apart from extra cognitive load in reasoning the operation. The fact is that you can't prevent developers from using `>>>` upon negative elements since neither the JVMS nor the JLS prevents it. > May you provide a more concrete example to the utilisation of unsigned shift > on signed subword types, please. The example provided by @fg1417 in #7979 > seems to indicate the real intention is to right shifting unsigned bytes, > with the unsigned cast sometimes omitted (changed to a signed cast) because > the shift results are masked by a stricter mask immediately. Sorry, I can't show the detail of our customer's code. However, just image that someone would like to optimize some code segments of bytes/shorts `>>>`, how can you say there should be always non-negative operands? ------------- PR: https://git.openjdk.java.net/jdk/pull/8276
