190336 2018-10-07 06:39:41 -0700 [JSC][YARR] Support YarrJIT in sampling profiler 2021-07-16 18:20:42 -0700 1 1 1 Unclassified WebKit JavaScriptCore WebKit Nightly Build Unspecified Unspecified RESOLVED DUPLICATE 201702 P2 Normal --- 1 ysuzuki ysuzuki saam oldest_to_newest 1466927 0 ysuzuki 2018-10-07 06:39:41 -0700 ... 1466943 1 ysuzuki 2018-10-07 09:24:03 -0700 When running uglify-js / coffeescript in web-tooling-benchmark, so much time is consumed in '#<nil>:None:<nil>'. Sampling rate: 1000.000000 microseconds Hottest bytecodes as <numSamples 'functionName#hash:JITType:bytecodeIndex'> 2441 'Function#<nil>:None:<nil>' 642 '#<nil>:None:<nil>' 462 'stringify#<nil>:None:<nil>' 188 'defaults#EZuPgj:FTL:755' 174 'push#EmOCkn:FTL:58' 155 'quote#A7WHiP:Baseline:62 <-- compareTo#EmCQ7y:FTL:174' 112 'compareTo#EmCQ7y:FTL:192' 98 'is_unicode_combining_mark#CdiBr0:Baseline:43 <-- is_identifier_char#BBa5RX:FTL:123' 95 '#Am9gS7:Baseline:10 <-- doit#At6wj3:FTL:76' 84 'OutputStream#D03V2N:FTL:1420' 71 'push#EmOCkn:FTL:114' 70 'push#EmOCkn:FTL:180' 69 'pop#CxNXKP:Baseline:85 <-- #D43Ncu:FTL:218' 64 '_visit#AK9Sj2:FTL:100' 61 'indexOf#<nil>:None:<nil>' This is actually YarrJIT RegExp execution. We would like to have more detailed results for this time, like, "What RegExp takes much time?". 1467522 2 saam 2018-10-09 12:50:31 -0700 That would be nice. I thought the sampling profiler knows when it's in the YARR? 1777688 3 ysuzuki 2021-07-16 18:20:42 -0700 *** This bug has been marked as a duplicate of bug 201702 ***