On Monday, 7 January 2019 at 23:20:57 UTC, H. S. Teoh wrote:
On Mon, Jan 07, 2019 at 11:13:37PM +0000, Guillaume Piolat via
Digitalmars-d-learn wrote:
On Monday, 7 January 2019 at 14:39:07 UTC, Per Nordlöw wrote:
> What's the preferred way of doing bitwise rotate of an
> integral value in D?
>
> Are there intrinsics for bitwise rotation available in LDC?
Turns out you don't need any:
https://d.godbolt.org/z/C_Sk_-
Generates ROL instruction.
There's a certain pattern that dmd looks for, that it
transforms into a ROL instruction. Similarly for ROR. Deviate
too far from this pattern, though, and it might not recognize
it as it should. To be sure, always check the disassembly.
Are you sure it's dmd looking for the pattern. Playing with the
godbolt link shows that dmd doesn't generate the rol code (gdc
4.8.2 neither).
