Properly handle postfix inc/dec in standalone and subexpr scenarios #104875
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…nd subexpr scenarios
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| let prev_is_semi = { | ||
| if let Ok(prev_code) = self.sess.source_map().span_to_prev_source(lhs.span) && | ||
| prev_code.trim_end().ends_with(";") { | ||
| true | ||
| } else { | ||
| false | ||
| } | ||
| }; |
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This is a bit of a hack, but fair given where it lives. I would like to do a perf run of an alternative approach: modify lhs to hold a starts_statement: bool field. I think that it might hit memory a bit, but that would be far less brittle to refactors breaking this heuristic. Would you have time to try doing that as part of this PR?
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You means add a field with boolean type to LhsExpr type?
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Updated the code.
I don't think there is a perf regerssion here, we are at error report codepath,
but you may have a double-check.
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Yes, maybe cost a little bit more memory.
| --> $DIR/issue-104867-inc-dec-2.rs:18:18 | ||
| | | ||
| LL | let _ = i + i++; | ||
| | ^^ not a valid postfix operator |
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This is the hardest case to handle well, so I removed the suggestion for this scenario.
There maybe a solution to get it right, I think it may not worth to do it.
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@bors r+ |
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☀️ Test successful - checks-actions |
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Finished benchmarking commit (309c469): comparison URL. Overall result: no relevant changes - no action needed@rustbot label: -perf-regression Instruction countThis benchmark run did not return any relevant results for this metric. Max RSS (memory usage)ResultsThis is a less reliable metric that may be of interest but was not used to determine the overall result at the top of this comment.
CyclesThis benchmark run did not return any relevant results for this metric. |
…estebank Properly handle postfix inc/dec in standalone and subexpr scenarios Fixes rust-lang#104867 r? `@estebank`
Fixes #104867
r? @estebank