[PATCH] D65591: [AST] Add a flag indicating if any subexpression had errors

Mon Aug 12 06:50:58 PDT 2019

riccibruno added a comment.

In D65591#1625183 <https://reviews.llvm.org/D65591#1625183>, @aaron.ballman wrote:

> In D65591#1625154 <https://reviews.llvm.org/D65591#1625154>, @riccibruno wrote:
>
> > It seems that these two options are not exactly the same right ? The `ContainsError` bit is useful to quickly answer "Does this expression contains an invalid sub-expression" without doing the search, while adding an `ErrorExpr` node is useful to note that //this// sub-expression is invalid (and as Aaron says the hypothetical `ErrorExpr` node can carry more info about the error).
>
>
> That's true. I had figured that answering "does this expression contain an invalid sub-expression" could be implemented with a walk of the expression tree rather than consuming a bit. To consumers of `containsErrors()`, there shouldn't be much difference aside from performance (and that may be sufficient reason to go with a bit, but I think I'd like to see performance measurements that show the bit is necessary).

Fair enough, especially given that IIRC there are not many bits left in these bit-fields classes.

Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D65591/new/

https://reviews.llvm.org/D65591