Closed
Description
The main serde crate compiles in 10 seconds, 5 of which is ElaborateDrops. Is this expected? Is there anything we can do on our end to reduce this? I don't see any other tickets about this pass in particular.
https://github.com/serde-rs/serde/tree/v0.8.12/serde
$ rustc --version
rustc 1.14.0-nightly (a3bc191b5 2016-10-10)
$ cargo rustc -- -Z time-passes
Compiling serde v0.8.12
time: 0.024; rss: 55MB parsing
time: 0.000; rss: 55MB recursion limit
time: 0.000; rss: 55MB crate injection
time: 0.000; rss: 55MB plugin loading
time: 0.000; rss: 55MB plugin registration
time: 0.199; rss: 97MB expansion
time: 0.000; rss: 97MB maybe building test harness
time: 0.002; rss: 97MB maybe creating a macro crate
time: 0.000; rss: 97MB checking for inline asm in case the target doesn't support it
time: 0.004; rss: 97MB complete gated feature checking
time: 0.008; rss: 97MB early lint checks
time: 0.003; rss: 97MB AST validation
time: 0.042; rss: 103MB name resolution
time: 0.026; rss: 113MB lowering ast -> hir
time: 0.006; rss: 116MB indexing hir
time: 0.002; rss: 116MB attribute checking
time: 0.003; rss: 98MB language item collection
time: 0.005; rss: 98MB lifetime resolution
time: 0.000; rss: 98MB looking for entry point
time: 0.000; rss: 98MB looking for plugin registrar
time: 0.021; rss: 103MB region resolution
time: 0.002; rss: 103MB loop checking
time: 0.002; rss: 103MB static item recursion checking
time: 0.110; rss: 103MB compute_incremental_hashes_map
time: 0.000; rss: 103MB load_dep_graph
time: 0.032; rss: 105MB type collecting
time: 0.001; rss: 105MB variance inference
time: 0.039; rss: 109MB coherence checking
time: 0.286; rss: 110MB wf checking
time: 0.093; rss: 110MB item-types checking
time: 1.835; rss: 122MB item-bodies checking
time: 0.000; rss: 122MB drop-impl checking
time: 0.384; rss: 122MB const checking
time: 0.019; rss: 122MB privacy checking
time: 0.002; rss: 122MB stability index
time: 0.017; rss: 122MB intrinsic checking
time: 0.006; rss: 122MB effect checking
time: 0.078; rss: 122MB match checking
time: 0.022; rss: 118MB liveness checking
time: 0.486; rss: 118MB rvalue checking
time: 0.388; rss: 187MB MIR dump
time: 0.030; rss: 185MB SimplifyCfg
time: 0.076; rss: 184MB QualifyAndPromoteConstants
time: 0.050; rss: 184MB TypeckMir
time: 0.002; rss: 184MB SimplifyBranches
time: 0.014; rss: 184MB SimplifyCfg
time: 0.172; rss: 184MB MIR passes
time: 0.859; rss: 185MB borrow checking
time: 0.007; rss: 185MB reachability checking
time: 0.016; rss: 185MB death checking
time: 0.017; rss: 186MB stability checking
time: 0.000; rss: 186MB unused lib feature checking
time: 0.133; rss: 186MB lint checking
time: 0.000; rss: 186MB resolving dependency formats
time: 0.001; rss: 186MB NoLandingPads
time: 0.014; rss: 186MB SimplifyCfg
time: 0.017; rss: 187MB EraseRegions
time: 0.006; rss: 187MB AddCallGuards
time: 4.833; rss: 204MB ElaborateDrops
time: 0.001; rss: 204MB NoLandingPads
time: 0.031; rss: 195MB SimplifyCfg
time: 0.009; rss: 195MB InstCombine
time: 0.006; rss: 195MB Deaggregator
time: 0.001; rss: 195MB CopyPropagation
time: 0.005; rss: 195MB AddCallGuards
time: 0.001; rss: 195MB PreTrans
time: 4.927; rss: 195MB Prepare MIR codegen passes
time: 0.141; rss: 200MB write metadata
time: 0.016; rss: 201MB translation item collection
time: 0.001; rss: 201MB codegen unit partitioning
time: 0.001; rss: 203MB internalize symbols
time: 0.226; rss: 143MB translation
time: 0.000; rss: 143MB assert dep graph
time: 0.000; rss: 143MB serialize dep graph
time: 0.006; rss: 88MB llvm function passes [0]
time: 0.002; rss: 88MB llvm module passes [0]
time: 0.078; rss: 94MB codegen passes [0]
time: 0.001; rss: 95MB codegen passes [0]
time: 0.096; rss: 94MB LLVM passes
time: 0.000; rss: 94MB serialize work products
time: 0.011; rss: 93MB linking
Finished debug [unoptimized + debuginfo] target(s) in 10.71 secs