On Mon, Feb 8, 2016 at 3:35 PM, David Blaikie <dblai...@gmail.com> wrote: > > > On Mon, Feb 8, 2016 at 3:21 PM, Xinliang David Li <davi...@google.com> > wrote: >> >> On Mon, Feb 8, 2016 at 3:17 PM, David Blaikie <dblai...@gmail.com> wrote: >> > >> > >> > On Mon, Feb 8, 2016 at 12:07 PM, Xinliang David Li <davi...@google.com> >> > wrote: >> >> >> >> On Mon, Feb 8, 2016 at 11:39 AM, David Blaikie <dblai...@gmail.com> >> >> wrote: >> >> > >> >> > >> >> > On Mon, Feb 8, 2016 at 9:25 AM, David Li via llvm-commits >> >> > <llvm-comm...@lists.llvm.org> wrote: >> >> >> >> >> >> davidxl updated this revision to Diff 47217. >> >> >> davidxl added a comment. >> >> >> >> >> >> Simplified test case suggested by Vedant. >> >> >> >> >> >> >> >> >> http://reviews.llvm.org/D16947 >> >> >> >> >> >> Files: >> >> >> lib/CodeGen/CGClass.cpp >> >> >> test/Profile/def-assignop.cpp >> >> >> >> >> >> Index: test/Profile/def-assignop.cpp >> >> >> =================================================================== >> >> >> --- test/Profile/def-assignop.cpp >> >> >> +++ test/Profile/def-assignop.cpp >> >> >> @@ -0,0 +1,32 @@ >> >> >> +// RUN: %clang_cc1 -x c++ -std=c++11 %s -triple >> >> >> x86_64-unknown-linux-gnu >> >> >> -main-file-name def-assignop.cpp -o - -emit-llvm >> >> >> -fprofile-instrument=clang >> >> >> | FileCheck --check-prefix=PGOGEN %s >> >> >> +// RUN: %clang_cc1 -x c++ -std=c++11 %s -triple >> >> >> x86_64-unknown-linux-gnu >> >> >> -main-file-name def-assignop.cpp -o - -emit-llvm >> >> >> -fprofile-instrument=clang >> >> >> -fcoverage-mapping | FileCheck --check-prefix=COVMAP %s >> >> >> + >> >> >> +struct B { >> >> >> + void operator=(const B &b) {} >> >> >> + void operator=(const B &&b) {} >> >> > >> >> > >> >> > Probably best to make these canonical to avoid confusion: >> >> > >> >> > B &operator=(const B&); >> >> > B &operator=(B&&); >> >> > >> >> > (& they don't need definitions - just declarations) >> >> >> >> Will change. >> >> >> >> > >> >> > Also, neither of these are the move /constructor/, just the move >> >> > operator. >> >> > Not sure if Vedant just used the wrong terminology, or whether it's >> >> > worth >> >> > testing the move/copy ctors too, to check that they do the right >> >> > thing >> >> > as >> >> >> >> I added tests for copy ctors, and plan to add move ctor test soon. >> >> >> >> > well. (if all of these things use the same codepath, I don't see a >> >> > great >> >> > benefit in having separate tests for them (but you can add them here >> >> > if >> >> > you >> >> > like) - I'm just suggesting a manual verification in case those need >> >> > a >> >> > separate fix >> >> >> >> the ctor and assignment op do not share the same path -- the ctor path >> >> is working as expected without the fix -- or do you mean there is no >> >> need to cover both copy and move variants? >> > >> > >> > I wouldn't necessarily bother testing multiple instances of the same >> > codepath (so the copy and move ctor for example) - but 2 instances is no >> > big >> > deal (if there were several more, I might be inclined to just test one >> > as a >> > representative sample). I don't mind either way, though. The number is >> > small >> > & the test cases are arguably distinct. >> >> Sorry I disagree with your general statement here. I treat such test >> cases as 'black box testing' that do not know about the internal >> implementation (code path). It may or may not share the same code path >> today -- same is true in the future. > > > While there's merit in both approaches, practically speaking it seems > difficult to test in that way in general - any feature could interact with > any other.
The language features are well specified -- so writing small test cases to cover them is a general accepted way of testing. >The LLVM regression suite is far more narrowly targeted than that > - we don't test combinations of optimizations, for example - we test each > optimization in isolation. The same would be true of two independent > features on an interface such as this, I think. This is a weakness of the test system -- a problem at a different dimension. > >> >> >> > >> >> >> >> > >> >> >> >> >> >> +}; >> >> >> + >> >> >> +struct A { >> >> >> + A &operator=(const A &) = default; >> >> > >> >> > >> >> > Is the fix/codepath specifically about explicitly defaulted ops? >> >> >> >> yes -- explicitly defaulted. There are some test coverage already for >> >> implicitly declared ctors (but not assignment op -- probably worth >> >> adding some testing too). >> > >> > >> > Hmm - are you sure there's no common codepath that would cover the >> > explicitly defaulted or implicitly defaulted ops together in one go? >> >> Sorry I am not sure what you mean here. > Is there some part of Clang that is responsible for generating both > implicitly defaulted and explicitly defaulted move/copy ops that could > handle this case, rather than apparently handling the implicit and explicit > cases separately (it seems they're being handled separately if the implicit > case worked before and you added code (rather than moving code) to fix the > explicit case - it sounds like we now have two bits of code, one for > implicit and one for explicit - perhaps there's a single bit of code that we > could write that would handle both?) The codegen paths are different -- otherwise as you commented, the implicit case would have been broken too. Refactoring FE code to handle both is probably beyond the scope of this fix. Having a good test case here will exactly help avoid regression if that happens in the future. David > > - David > >> >> >> David >> >> > >> >> >> >> >> >> > Or just any >> >> > compiler-generated ones? (you could drop these lines if it's about >> >> > any >> >> > compiler-generated ones, might be simpler/more obvious that it's not >> >> > about >> >> > the "= default" feature) >> >> >> >> Other compiler generated ones are handled differently. >> >> >> >> thanks, >> >> >> >> David >> >> >> >> > >> >> >> >> >> >> + // PGOGEN: define {{.*}}@_ZN1AaSERKS_( >> >> >> + // PGOGEN: %pgocount = load {{.*}} @__profc__ZN1AaSERKS_ >> >> >> + // PGOGEN: {{.*}}add{{.*}}%pgocount, 1 >> >> >> + // PGOGEN: store{{.*}}@__profc__ZN1AaSERKS_ >> >> >> + A &operator=(A &&) = default; >> >> >> >> >> >> + // PGOGEN: define {{.*}}@_ZN1AaSEOS_ >> >> >> + // PGOGEN: %pgocount = load {{.*}} @__profc__ZN1AaSEOS_ >> >> >> + // PGOGEN: {{.*}}add{{.*}}%pgocount, 1 >> >> >> + // PGOGEN: store{{.*}}@__profc__ZN1AaSEOS_ >> >> >> + >> >> >> + // Check that coverage mapping includes 6 function records >> >> >> including >> >> >> the >> >> >> + // defaulted copy and move operators: A::operator= >> >> >> + // COVMAP: @__llvm_coverage_mapping = {{.*}} { { i32, i32, i32, >> >> >> i32 >> >> >> }, >> >> >> [5 x <{{.*}}>], >> >> >> + B b; >> >> >> +}; >> >> >> + >> >> >> +int main() { >> >> >> + A a1, a2; >> >> >> + a1 = a2; >> >> >> + a2 = static_cast<A &&>(a1); >> >> > >> >> > >> >> > An option, though not necessarily better, would be to just take the >> >> > address >> >> > of the special members: >> >> > >> >> > auto (B::*x)(const B&) = &bar::operator=; >> >> > auto (B::*x)(B&&) = &bar::operator=; >> >> > >> >> > In short, what I'm picturing, in total: >> >> > >> >> > struct A { >> >> > A &operator=(const A&); >> >> > A &operator=(A&&); >> >> > }; >> >> > >> >> > struct B { >> >> > A a; >> >> > }; >> >> > >> >> > auto (B::*x)(const B&) = &B::operator=; >> >> > auto (B::*x)(B&&) = &B::operator=; >> >> > >> >> > Also, this test should probably be in clang, since it's a clang code >> >> > change/fix. >> >> > >> >> > >> >> >> >> >> >> + return 0; >> >> >> +} >> >> >> Index: lib/CodeGen/CGClass.cpp >> >> >> =================================================================== >> >> >> --- lib/CodeGen/CGClass.cpp >> >> >> +++ lib/CodeGen/CGClass.cpp >> >> >> @@ -1608,6 +1608,7 @@ >> >> >> >> >> >> LexicalScope Scope(*this, RootCS->getSourceRange()); >> >> >> >> >> >> + incrementProfileCounter(RootCS); >> >> >> AssignmentMemcpyizer AM(*this, AssignOp, Args); >> >> >> for (auto *I : RootCS->body()) >> >> >> AM.emitAssignment(I); >> >> >> >> >> >> >> >> >> >> >> >> _______________________________________________ >> >> >> llvm-commits mailing list >> >> >> llvm-comm...@lists.llvm.org >> >> >> http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-commits >> >> >> >> >> > >> > >> > > > _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits