On Wed, 3 Nov 2021, Kito Cheng wrote: > > Also are we missing explicit test coverage here? Or is it supposed to > > be covered by the generic tests here or there already (I'm not familiar > > with the details of the ISA extension to tell offhand), as long as the > > extension has been enabled for the target tested, and it is just that > > the problem has slipped through somehow? > > Cost model is not easy to test (at least to me :p), I usually verify > that by check the dump of combine pass to make sure the cost is right.
Fair enough. Note that intermediate dumps can be used for automatic verification too, with `scan-tree-dump', `scan-rtl-dump', etc. (I guess you probably knew that already). I know that writing a good test case can be tricky. Maciej