Test failed as D52120 made ExprMutationAnalyzer smarter, fixed by:
- Add move-ctor for `Mutable` to make it actually movable.
- Properly implement `remove_reference`.
The failed test case is:
void negativeVarIsMoved() {
for (auto M : View<Iterator<Mutable>>()) {
auto Moved = std::move(M);
}
}
Before D52120, `std::move(M)` itself is considered as a mutation to `M`,
while after D52120 it's only considered as a cast to rvalue, the
move-assignment is what causes the actual mutation. The test case didn't
mock things properly so the intended move-assignement was actually a
copy-assignment.
llvm-svn: 342417
performance-for-range-copy check.
Summary:
The upstream change r336737 make the check too smart to fix the case
where loop variable could be used as `const auto&`.
But for the case below, changing to `const auto _` will introduce
an unused complier warning.
```
for (auto _ : state) {
// no references for _.
}
```
This patch omit this case, and it is safe to do it as the case is very rare.
Reviewers: ilya-biryukov, alexfh
Subscribers: xazax.hun, cfe-commits
Differential Revision: https://reviews.llvm.org/D50447
llvm-svn: 339415
Summary:
This gives better coverage to the check as ExprMutationAnalyzer is more
accurate comparing to isOnlyUsedAsConst.
Majority of wins come from const usage of member field, e.g.:
for (auto widget : container) { // copy of loop variable
if (widget.type == BUTTON) { // const usage only recognized by ExprMutationAnalyzer
// ...
}
}
Reviewers: george.karpenkov
Subscribers: a.sidorin, cfe-commits
Differential Revision: https://reviews.llvm.org/D48854
llvm-svn: 336737
Summary:
Fix oversight not checking the value of the Optional<bool> returned by
isExpensiveToCopy().
Reviewers: alexfh
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D17064
llvm-svn: 260870
Shuai Wang