[PATCH] D150635: [clangd] Implement end-definition-comment inlay hints

[Qingyuan Zheng via Phabricator via cfe-commits]

daiyousei-qz added inline comments.


================
Comment at: clang-tools-extra/clangd/InlayHints.cpp:616
+    Position HintStart = sourceLocToPosition(SM, BraceRange.getEnd());
+    Position HintEnd = {HintStart.line,
+                        HintStart.character +
----------------
sammccall wrote:
> please don't do this, call sourceLocToPosition unless you have benchmarks showing this is a bottleneck on real-world code.
> 
> `lspLength` and direct manipulation of line/character is unneccesarily subtle.
> (If the performance matters, there's no need to be computing the LSP line of the lbrace at all - we never use it - this is one reason I think this function has the wrong signature)
I argue performance does matter here. I eye-balled inlay hint compute time in clangd's output window from vscode. On "./clang/lib/Sema/SemaOpenMP.cpp" which is around 1MB, using `sourceLocToPosition` roughly takes around 1250~1350ms. However, using two `offsetLocToPosition` usually use 1400~1500ms.  I think 100ms delta is already a noticeable difference.


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  https://reviews.llvm.org/D150635/new/

https://reviews.llvm.org/D150635