On 30 November 2017 at 04:29, Walter Bright via Digitalmars-d <digitalmars-d@puremagic.com> wrote: > On 11/29/2017 7:15 PM, Jonathan M Davis wrote: >> >> I wouldn't have expected assertions to cost much more than however much it >> costs to evaluate the expression being asserted unless the assertion >> fails. >> Now, even that can slow down a program a fair bit, depending on what's >> being >> asserted and how many assertions there are, but it's not something that I >> would have expected to vary particular between C and D. It doesn't >> surprise >> me that the generated code would be larger than you'd get for the same >> assertions in C because how assertions are handled when they fail is quite >> different, but I would expect the assertions themselves to cost about the >> same in terms of performance as long as they don't fail. What's going on >> that's making them so much worse? > > > The code *size* causes problems because it pushes the executing code out of > the cache. Another issue (I should check this again) was doing null checks > on member function calls, which is not necessary since if they're null it'll > seg fault. >
This is only a problem if you (dmd) are not able to move code blocks into hot and cold paths?
