这是 v8-module -trace-opt index.js 的输出。您可以看到函数的优化 COONSURRANDOM和COONMALINMJS 已完成。
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[completed optimizing 0x2b0e0824a769 <JSFunction commonRandom (sfi = 0x2b0e081d3985)> (target TURBOFAN)]
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[completed optimizing 0x2b0e0824a789 <JSFunction commonRandomJS (sfi = 0x2b0e081d39b9)> (target TURBOFAN)]
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这是 v8-module -trace-deopt index.js 的输出。您可以看到函数 commonRandom和commonRandomjs 没有被解开。
[bailout (kind: deopt-soft, reason: Insufficient type feedback for compare operation): begin. deoptimizing 0x3907082827f9 <JSFunction randomMatrix (sfi = 0x3907081d39ed)>, opt id 0, bytecode offset 167, deopt exit 35, FP to SP delta 208, caller SP 0x7ffee6068410, pc 0x39070004611c]
[bailout (kind: deopt-soft, reason: Insufficient type feedback for compare operation): begin. deoptimizing 0x39070824a839 <JSFunction randomMatrix (sfi = 0x3907081d39ed)>, opt id 2, bytecode offset 249, deopt exit 28, FP to SP delta 208, caller SP 0x7ffee6068410, pc 0x390700047265]
[bailout (kind: deopt-soft, reason: Insufficient type feedback for unary operation): begin. deoptimizing 0x39070824a839 <JSFunction randomMatrix (sfi = 0x3907081d39ed)>, opt id 3, bytecode offset 349, deopt exit 23, FP to SP delta 264, caller SP 0x7ffee6068410, pc 0x390700047d5b]
我已经根据 -Trace-Opt/ - Trace-Deopt 标志。 howether， kturbofanded flag是 0 ，但是 koptimized和kmaglevved 都是 1S 。为什么是这样？ kturbofanned ， koptimized 和 kmaglevved 标志的含义是什么？
方向：
V8版本9.9.67
This is the output of v8 --module --trace-opt index.js. You can see that optimization of functions commonRandom and commonRandomJS was completed.
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[completed optimizing 0x2b0e0824a769 <JSFunction commonRandom (sfi = 0x2b0e081d3985)> (target TURBOFAN)]
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[completed optimizing 0x2b0e0824a789 <JSFunction commonRandomJS (sfi = 0x2b0e081d39b9)> (target TURBOFAN)]
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This is the output of v8 --module --trace-deopt index.js. You can see that functions commonRandom and commonRandomJS were not deopted.
[bailout (kind: deopt-soft, reason: Insufficient type feedback for compare operation): begin. deoptimizing 0x3907082827f9 <JSFunction randomMatrix (sfi = 0x3907081d39ed)>, opt id 0, bytecode offset 167, deopt exit 35, FP to SP delta 208, caller SP 0x7ffee6068410, pc 0x39070004611c]
[bailout (kind: deopt-soft, reason: Insufficient type feedback for compare operation): begin. deoptimizing 0x39070824a839 <JSFunction randomMatrix (sfi = 0x3907081d39ed)>, opt id 2, bytecode offset 249, deopt exit 28, FP to SP delta 208, caller SP 0x7ffee6068410, pc 0x390700047265]
[bailout (kind: deopt-soft, reason: Insufficient type feedback for unary operation): begin. deoptimizing 0x39070824a839 <JSFunction randomMatrix (sfi = 0x3907081d39ed)>, opt id 3, bytecode offset 349, deopt exit 23, FP to SP delta 264, caller SP 0x7ffee6068410, pc 0x390700047d5b]
I've implemented my own tracing script according to https://github.com/v8/v8/blob/207f489fc5df0cab30b9cde373181c0242c0874c/src/runtime/runtime.h#L897 %GetOptimizationStatus current implementation and used the same number of iterations as with --trace-opt/--trace-deopt flags. Howether, the kTurboFanned flag is 0, but kOptimized and kMaglevved are both 1s. Why is it so? What does kTurbofanned, kOptimized and kMaglevved flags mean then?
Verions:
V8 version 9.9.67
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像往常一样，V8是在积极发展的基础上。要解释9.9.67的
％getOptimizationStatus输出，请参阅Runtime.h的正确版本。 /runtime.h 。“ Maglev”是一个新的编译器，仍在开发中，并在火花插花和Turbofan之间进行插槽。版本9.9.x还没有。
V8 is, as it has always been, under active development. To interpret 9.9.67's
%GetOptimizationStatusoutput, refer to the correct version of runtime.h:https://github.com/v8/v8/blob/9.9.67/src/runtime/runtime.h."Maglev" is a new compiler, still under development, and slotting in between Sparkplug and Turbofan. Version 9.9.x didn't have it yet.