Cache more results of const_eval #9722
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According to http://huonw.github.io/isrustfastyet/mem/#012f909, the "const marking" pass generates about 400MB of extra memory during compilation. It appears that this is due to two different factors: 1. There is a `ccache` map in the ty::ctxt which is only ever used in this pass, so this commit moves the map out of the ty::ctxt struct and into just this pass's visitor. This turned out to not benefit that much in memory (as indicated by http://i.imgur.com/Eo4iOzK.png), but it's helpful to do nonetheless. 2. During const_eval, there are a lot of lookups into decoding inlined items from external crates. There is no caching involved here, so the same static or variant could be re-translated many times. After adding separate caches for variants and statics, the memory peak of compiling rustc decreased by 200MB (as evident by http://i.imgur.com/ULAUMtq.png) The culmination of this is basically a slight reorganization of a caching map for the const_eval pass along with a 200MB decrease in peak memory usage when compiling librustc.
bors
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Oct 5, 2013
According to http://huonw.github.io/isrustfastyet/mem/#012f909, the "const marking" pass generates about 400MB of extra memory during compilation. It appears that this is due to two different factors: 1. There is a `ccache` map in the ty::ctxt which is only ever used in this pass, so this commit moves the map out of the ty::ctxt struct and into just this pass's visitor. This turned out to not benefit that much in memory (as indicated by http://i.imgur.com/Eo4iOzK.png), but it's helpful to do nonetheless. 2. During const_eval, there are a lot of lookups into decoding inlined items from external crates. There is no caching involved here, so the same static or variant could be re-translated many times. After adding separate caches for variants and statics, the memory peak of compiling rustc decreased by 200MB (as evident by http://i.imgur.com/ULAUMtq.png) The culmination of this is basically a slight reorganization of a caching map for the const_eval pass along with a 200MB decrease in peak memory usage when compiling librustc.
Newly having a third-party directory was throwing off the unpack script
bors
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Oct 5, 2013
According to http://huonw.github.io/isrustfastyet/mem/#012f909, the "const marking" pass generates about 400MB of extra memory during compilation. It appears that this is due to two different factors: 1. There is a `ccache` map in the ty::ctxt which is only ever used in this pass, so this commit moves the map out of the ty::ctxt struct and into just this pass's visitor. This turned out to not benefit that much in memory (as indicated by http://i.imgur.com/Eo4iOzK.png), but it's helpful to do nonetheless. 2. During const_eval, there are a lot of lookups into decoding inlined items from external crates. There is no caching involved here, so the same static or variant could be re-translated many times. After adding separate caches for variants and statics, the memory peak of compiling rustc decreased by 200MB (as evident by http://i.imgur.com/ULAUMtq.png) The culmination of this is basically a slight reorganization of a caching map for the const_eval pass along with a 200MB decrease in peak memory usage when compiling librustc.
flip1995
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Nov 21, 2022
`question_mark` don't lint on `if let Err` with `else` cc rust-lang#9518 AFAICT the only time this would be a valid suggestion is the rather esoteric ```rust let _ = if let Err(e) = x { return Err(e); } else { // no side effects x.unwrap() } ``` which doesn't seem worth checking to me. Please correct me if I'm missing something. changelog: [`question_mark`] don't lint on `if let Err` with `else`
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According to http://huonw.github.io/isrustfastyet/mem/#012f909, the "const
marking" pass generates about 400MB of extra memory during compilation. It
appears that this is due to two different factors:
The culmination of this is basically a slight reorganization of a caching map
for the const_eval pass along with a 200MB decrease in peak memory usage when
compiling librustc.