m.ostapenko added a comment. In https://reviews.llvm.org/D16403#1011218, @NoQ wrote:
> In https://reviews.llvm.org/D16403#1010096, @szepet wrote: > > > In https://reviews.llvm.org/D16403#992454, @NoQ wrote: > > > > > @szepet: so i see that `LoopExit` goes in the beginning of the cleanup > > > block after the loop, while various `ScopeEnd`s go after the `LoopExit`. > > > Would loop unrolling be significantly broken if you simply subscribe to > > > `ScopeEnd` instead of `LoopExit` and avoid cleaning up the loop state > > > until destructors are processed? I might not be remembering correctly - > > > is `LoopExit` only used for cleanup, or do we have more work to be done > > > here? > > > > > > I guess your following comment just answers this: > > > > In https://reviews.llvm.org/D16403#1001466, @NoQ wrote: > > > > > We still don't have scopes for segments of code that don't have any > > > variables in them, so i guess it's not yet in the shape where it is super > > > useful for loops, but it's already useful for finding use of stale stack > > > variables, which was the whole point originally, so i think this should > > > definitely land soon. > > > > > > It could be, however, we would lose cases like: > > > > int i = 0; > > int a[32]; > > for(i = 0;i<32;++i) {a[i] = i;} > > > > > > Since there is no variable which has the scope of the loop, ScopeEnd would > > be not enough. Sure, we could remove this case, however, the aim is to > > extend the loop-patterns for completely unrolling. Another thing that there > > are the patches which would enhance the covered cases by LoopExit > > (https://reviews.llvm.org/D39398) and add the LoopEntrance to the > > CFG(https://reviews.llvm.org/D41150) as well. So, at this point, I feel > > like it would be a huge step back not to use these elements. (Sorry Maxim > > that we are discussing this here^^) > > > Yeah, i mean, like, if we change the scope markers to also appear even when > no variables are present in the scope, then it would be possible to replace > loop markers with some of the scope markers, right? Hm, so does this mean that I need to cover the case when no variables are present in loop scope here in this patch? Repository: rL LLVM https://reviews.llvm.org/D16403 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
