@optimal/fn

Force V8 to try to optimize a function and check optimization status in nodes 4, 6, 7, and 8.

Use in benchmarking to optimize before running the benchmark.

Use in analysis to test if your functions can be optimized.

See tests for examples of what optimizes and what doesn't. [JS] [CS]

See:

1. article
2. another article
3. node benchmark helper

4. node 8+ runtime/runtime.h for new optimization status bit mask

    enum class OptimizationStatus {
      kIsFunction = 1 << 0,      // 1
      kNeverOptimize = 1 << 1,   // 2
      kAlwaysOptimize = 1 << 2,  // 4
      kMaybeDeopted = 1 << 3,    // 8
      kOptimized = 1 << 4,       // 16
      kTurboFanned = 1 << 5,     // 32
      kInterpreted = 1 << 6,     // 64
      kMarkedForOptimization = 1 << 7,            //  128
      kMarkedForConcurrentOptimization = 1 << 8,  //  256
      kOptimizingConcurrently = 1 << 9,           //  512
      kIsExecuting = 1 << 10,                     // 1024
      kTopmostFrameIsTurboFanned = 1 << 11,       // 2048
    };

Install

npm install @optimal/fn --save

Usage

// 1. attempt to optimize a function and get its status
var optimize = require('@optimal/fn')

function fn() { }

var result = optimize(fn)

console.log(result)
// {
//    optimized: true,
//    always   : false,
//    maybe    : false,
//    TurboFan : false
// }

// 2. test a function to see if it's optimized:
var someOtherFn = getSomeOtherFn()
result = optimize.check(someOtherFn)

Result Properties

The result may contain these properties:

1. optimized - true when optimized, false otherwise
2. always - When function "is optimized" then always will be false. When function is "always optimized" then always will be true. When function will "never be optimized" then always is true (and optimized is false).
3. maybe - when function is "maybe deoptimized" then maybe is true, otherwise it is false.
4. TurboFan - when function is "optimized by TurboFan" then this is true, otherwise it is false.

MIT License

0.3.1 - 2018/07/15

1. update dev deps
2. fix mocha test args (missing *.coffee)
3. remove node 9, add node 10
4. update node version processing for double digit version
5. update test values for node 10's differences
6. remove Gemnasium badge (Gemnasium bought by GitLab...)
7. Link license header in README to the LICENSE file

0.3.0 - 2018/02/05

1. update deps
2. update mocha call args (replace --compilers with --require)
3. update node versions tested (remove 7, add 9)
4. move node version handling and answer building to helpers.coffee.
5. update testing for new ability to optimize for different node versions.

0.2.0 - 2017/05/31

1. add new implementation for node 8 which uses a bit mask instead of a single value.
2. adapt testing for new implementation tested on node 8
3. change tests because newer minor releases of nodes 4, 6, and 7 now optimize some things they didn't before
4. add linting
5. add node 8 to Travis CI, change script configuration, cache node_modules
6. add link to runtime/runtime.h in V8's source where the new optimization status enum is defined

0.1.0 - 2017/01/01

1. initial working version with tests with 100% coverage