dexonsmith added a comment. In D82756#2361565 <https://reviews.llvm.org/D82756#2361565>, @jansvoboda11 wrote:
> Thanks for the feedback Duncan. > > I don't think this patch introduces any changes the parser. We only change > the way how `CodeGenOpts` and `LangOpts` get populated when using > `DefaultAnyOf<[...]>`. I've added a test of `CompilerInvocation` that checks > just that. The test for `CompilerInvocation` looks great, but IMO it's insufficient. Given that the changes are in `llvm/`, it seems best to have a test there so that `check-llvm` (also) catches any breakage. I took a look at `llvm/unittests/Option/Opts.td` and `llvm/unittests/Option/OptionParsingTest.cpp` and I see we don't currently have any tests for marshalling, but my intuition is it wouldn't be hard to do. What I suggest is adding `OptionMarshallingTest.cpp` and just test the new behaviour from this commit (key properties of the changes you made to `OptParser.td` and `OptParserEmitter.cpp`), leaving testing the rest for some follow-up. ================ Comment at: clang/include/clang/Driver/Options.td:1176 +defm reciprocal_math : OptInFFlag< "reciprocal-math", "Allow division operations to be reassociated", "", "", [], "LangOpts->AllowRecip">; +def fapprox_func : Flag<["-"], "fapprox-func">, Group<f_Group>, Flags<[CC1Option, NoDriverOption]>, + MarshallingInfoFlag<"LangOpts->ApproxFunc", "false">; ---------------- jansvoboda11 wrote: > dexonsmith wrote: > > dang wrote: > > > Anastasia wrote: > > > > could this also be OptInFFlag? > > > The aim was to keep the driver semantics the same as before and this was > > > not something you could control with the driver, so I left it as just a > > > CC1 flag. However if it makes sense to be able to control this from the > > > driver then we can definitely make this `OptInFFLag`. > > I think adding a driver flag (if that's the right thing to do) should be > > done separately in a follow-up commit. > > > > Also for a separate commit: it would be a great improvement if you could > > have OptIn / OptOut flags that were `-cc1`-only (maybe `CC1OptInFFlag`). > > - Both `-fX` and `-fno-X` would be parsed by `-cc1` (and cancel each other > > out). > > - Only the non-default one would be generated when serializing to `-cc1` > > from `CompilerInvocation` (for `OptIn`, we'd never generate `-fno-X`). > > - Neither would be recognized by the driver. > > > > I suggest we might want that for most `-cc11` flags. This would make it > > easier to poke through the driver with `-Xclang` to override `-cc1` options > > the driver adds. Not something we want for end-users, but useful for > > debugging the compiler itself. Currently the workflow is to run the driver > > with `-###`, copy/paste, search for and remove the option you want to skip, > > and finally run the `-cc1` command... > > > > The reason I bring it up is that it's possible people will start using > > `OptInFFLag` just in order to get this behaviour, not because they intend > > to add a driver flag. > I agree that making all `OptInFFlag` and `OptOutFFlag` driver flags as well > as `-cc1` flags by default is not great. How would we go about deciding which > options are okay to demote to `-cc1`-only? Perhaps those not present in > `ClangCommandLineReference.rst` and driver invocations in tests? > How would we go about deciding which options are okay to demote to > `-cc1-only`? The key is not to add (or remove) driver options unintentionally. Driver options are `clang`'s public interface, and once an option shows up there we're supposed to support it "forever". We shouldn't be accidentally/incidentally growing that surface area in order to simplify parsing/generating `-cc1` command-lines. I based my comment on @dang's reason for not using `OptInFFLag`, which I agree with: > The aim was to keep the driver semantics the same as before and this was not > something you could control with the driver, so I left it as just a CC1 flag. ================ Comment at: llvm/utils/TableGen/OptParserEmitter.cpp:460-464 + if (AID < BID) + return -1; + if (AID > BID) + return 1; + return 0; ---------------- jansvoboda11 wrote: > dexonsmith wrote: > > I think `array_pod_sort` will use this like a `bool`, similar to > > `std::sort`, in which case you I think you want: > > ``` > > return (*A)->getID() < (*B)->getID(); > > ``` > I see that `array_pod_sort` calls `qsort` from the C standard library, which > should use the result of comparator as an `int`. Thanks, you're right, I misremembered `array_pod_sort` somehow reinterpreting the lambda... ================ Comment at: llvm/utils/TableGen/OptParserEmitter.cpp:468-469 + // Restore the definition order of marshalling options. + array_pod_sort(OptsWithMarshalling.begin(), OptsWithMarshalling.end(), + CmpMarshallingOpts); + ---------------- jansvoboda11 wrote: > dexonsmith wrote: > > I'm curious if this is necessary. If so, how do the options get > > out-of-order? > > > > Also, a cleaner way to call `array_pod_sort` would be: > > ``` > > llvm::sort(OptsWithMarshalling, CmpMarshallingOpts); > > ``` > > and I would be tempted to define the lambda inline in the call to > > `llvm::sort`. > > > > If it's not necessary, I suggest replacing with an assertion: > > ``` > > assert(llvm::is_sorted(OptsWithMarshalling, ...)); > > ``` > 1. The options get out of order during parsing. The `RecordKeeper` stores > records in `std::map<std::string, std::unique_ptr<Record>, std::less<>>` that > maintains lexicographical order. > > 2. Later, they are reordered in this function before prefix groups are > generated: `array_pod_sort(Opts.begin(), Opts.end(), CompareOptionRecords);`. > > 3. Before we generate the marshalling code, we need to restore the definition > order so that we don't use a `LangOpts` or `CodeGenOpts` field (from > `DefaultAnyOf`) before it was initialized. > > I've added more detailed explanation to the comment. > > I used `array_pod_sort` to be consistent with what's already used here in > `OptParserEmitter.cpp`. I will switch to `llvm::sort` to be more concise if > we don't mind the potential code bloat described here > <https://llvm.org/doxygen/namespacellvm.html#add1eb5637dd671428b6f138ed3db6428>. Thanks for the explanation about the ordering, this makes sense. Regarding `array_pod_sort`, I was referring to how `llvm::sort` calls `array_pod_sort` when it can... but I hadn't noticed before that it can't do this for a custom comparator. You should stick with `array_pod_sort` (although maybe as a follow-up I'll look into whether we can detect if the custom comparator to `llvm::sort` is stateless and defer to `array_pod_sort` in that case as well...) CHANGES SINCE LAST ACTION https://reviews.llvm.org/D82756/new/ https://reviews.llvm.org/D82756 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
