Log debug elapsed time using 2 decimal places #5200
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For flags like -debug-time-function-bodies, this makes it easier to measure the impact of parsing functions that take a short amount of time to parse (less than 0.1ms) but are parsed many times and therefore add up over the course of the full build.
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This also fixes SR-16 |
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Just to get this rolling @swift-ci please smoke test. |
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I deliberately picked short precision because this was really only for tracking long times, but the other reason to keep it short is to not imply precision that isn't there. On a regularly loaded system, times can vary quite a bit. How about two decimal places, or even just keeping one, but rounding up first? |
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I see. That makes sense. I'm only interested in ensuring that 0.0ms isn't logged, since it isn't that useful. Even though the precision might be there, the situation in which this data is useful is when you have lots of samples because of the nature of the bug. How about 2 decimal places + rounding? This'll give a bit more precision than exists now, while ensuring no 0 values. |
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Sounds good to me. Thanks, Ben! |
benasher44
changed the title
| @@ -155,7 +155,8 @@ namespace { | |||
| ASTContext &ctx = Function.getAsDeclContext()->getASTContext(); | |||
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| if (ShouldDump) { | |||
| llvm::errs() << llvm::format("%0.1f", elapsed * 1000) << "ms\t"; | |||
| // Round to the nearest 100th of a millisecond | |||
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Nitpick: comments should end with periods.
| @@ -155,7 +155,8 @@ namespace { | |||
| ASTContext &ctx = Function.getAsDeclContext()->getASTContext(); | |||
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| if (ShouldDump) { | |||
| llvm::errs() << llvm::format("%0.1f", elapsed * 1000) << "ms\t"; | |||
| // Round to the nearest 100th of a millisecond | |||
| llvm::errs() << llvm::format("%0.2f", round(elapsed * 100000) / 100) << "ms\t"; | |||
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I thought we settled on ceil?
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Oh I think I read over the "up" part in "rounding up." Will fix!
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@swift-ci Please smoke test |
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@swift-ci please smoke test. |
[pull] swiftwasm from main
-debug-time-function-bodiesis a useful flag for determining compile-time slowness, but it only logs elapsed parse times to 1/10th of a millisecond. While this is useful if a function takes a long time to parse, it doesn't help determine time lost to parsing function bodies that take a short time to parse (less than 0.1ms) but are parsed multiple times over the course of a build and therefore add up to occupying a significant portion of the build time.Changing this helped me determine the impact of SR-2901.
Resolves SR-16