On Tuesday, 8 January 2019 at 12:35:16 UTC, H. S. Teoh wrote:
On Tue, Jan 08, 2019 at 09:15:09AM +0000, Patrick Schluter via
Digitalmars-d-learn wrote:
On Monday, 7 January 2019 at 23:20:57 UTC, H. S. Teoh wrote:
[...]
> [...]
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).
I vaguely remember a bug about this. There is definitely
explicit checking for this in dmd; I don't remember if it was a
bug in the pattern matching code itself, or some other problem,
that made it fail. You may need to specify -O for the code to
actually be active. Walter could point you to the actual
function that does this optimization.
I did use the -O flag. The code generated did not use rol.
