github/boa - boa - 帆软第三方插件仓库

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Author	SHA1	Message	Date
Halid Odat	a2964e63dd	Implement instruction flowgraph generator (#2422 ) This PR is a WIP implementation of a vm instruction flowgraph generator This aims to make the vm easier to debug and understand for both newcomers and experienced devs. For example if we have the following code: ```js let i = 0; while (i < 10) { if (i == 3) { break; } i++; } ``` It generates the following instructions (which is hard to read, especially jumps): <details> ``` ----------------------Compiled Output: '<main>'----------------------- Location Count Opcode Operands 000000 0000 PushZero 000001 0001 DefInitLet 0000: 'i' 000006 0002 LoopStart 000007 0003 LoopContinue 000008 0004 GetName 0000: 'i' 000013 0005 PushInt8 10 000015 0006 LessThan 000016 0007 JumpIfFalse 78 000021 0008 PushDeclarativeEnvironment 0, 1 000030 0009 GetName 0000: 'i' 000035 0010 PushInt8 3 000037 0011 Eq 000038 0012 JumpIfFalse 58 000043 0013 PushDeclarativeEnvironment 0, 0 000052 0014 Jump 78 000057 0015 PopEnvironment 000058 0016 GetName 0000: 'i' 000063 0017 IncPost 000064 0018 RotateRight 2 000066 0019 SetName 0000: 'i' 000071 0020 Pop 000072 0021 PopEnvironment 000073 0022 Jump 7 000078 0023 LoopEnd Literals: <empty> Bindings: 0000: i Functions: <empty> ``` </details> And the flow graph is generated: ![flowgraph](https://user-images.githubusercontent.com/8566042/200589387-40b36ad7-d2f2-4918-a3e4-5a8fa5eee89b.png) The beginning of the function is marked by the `start` node (in green) and end (in red). In branching the "yes" branch is marked in green and "no" in red. ~~This only generates in [graphviz format](https://en.wikipedia.org/wiki/DOT_(graph_description_language)) (a widely used format) but it would be nice to also generate to a format that `mermaid.js` can understand and that could be put in articles https://github.com/boa-dev/boa-dev.github.io/issues/26~~ TODO: - [x] Generate graphviz format - [x] Generate mermaid format - [x] Programmatically generate colors push and pop env instructions - [x] Display nested functions in sub-sub-graphs. - [x] Put under a feature (`"flowgraph"`) - [x] Handle try/catch, switch instructions - [x] CLI option for configuring direction of flow (by default it is top down) - [x] Handle `Throw` instruction (requires keeping track of try blocks) - [x] Documentation - [x] Prevent node name collisions (functions with the same name)	2 years ago

Author

SHA1

Message

Date

Halid Odat

a2964e63dd

Implement instruction flowgraph generator (#2422 )

This PR is a WIP implementation of a vm instruction flowgraph generator

This aims to make the vm easier to debug and understand for both newcomers and experienced devs.

For example if we have the following code:
```js
let i = 0;
while (i < 10) {
    if (i == 3) {
        break;
    }
    i++;
}
```
It generates the following instructions (which is hard to read, especially jumps):
<details>

```
----------------------Compiled Output: '<main>'-----------------------
Location  Count   Opcode                     Operands

000000    0000    PushZero
000001    0001    DefInitLet                 0000: 'i'
000006    0002    LoopStart
000007    0003    LoopContinue
000008    0004    GetName                    0000: 'i'
000013    0005    PushInt8                   10
000015    0006    LessThan
000016    0007    JumpIfFalse                78
000021    0008    PushDeclarativeEnvironment 0, 1
000030    0009    GetName                    0000: 'i'
000035    0010    PushInt8                   3
000037    0011    Eq
000038    0012    JumpIfFalse                58
000043    0013    PushDeclarativeEnvironment 0, 0
000052    0014    Jump                       78
000057    0015    PopEnvironment
000058    0016    GetName                    0000: 'i'
000063    0017    IncPost
000064    0018    RotateRight                2
000066    0019    SetName                    0000: 'i'
000071    0020    Pop
000072    0021    PopEnvironment
000073    0022    Jump                       7
000078    0023    LoopEnd

Literals:
    <empty>

Bindings:
    0000: i

Functions:
    <empty>
```

</details>

And the flow graph is generated:
![flowgraph](https://user-images.githubusercontent.com/8566042/200589387-40b36ad7-d2f2-4918-a3e4-5a8fa5eee89b.png)

The beginning of the function is  marked by the `start` node (in green) and end (in red). In branching the "yes" branch is marked  in green and "no" in red.

~~This only generates in [graphviz format](https://en.wikipedia.org/wiki/DOT_(graph_description_language)) (a widely used format) but it would be nice to also generate to a format that `mermaid.js` can understand and that could be put in articles https://github.com/boa-dev/boa-dev.github.io/issues/26~~

TODO:
  - [x] Generate graphviz format
  - [x] Generate mermaid format
  - [x] Programmatically generate colors push and pop env instructions
  - [x] Display nested functions in sub-sub-graphs.
  - [x] Put under a feature (`"flowgraph"`)
  - [x] Handle try/catch, switch instructions
  - [x] CLI option for configuring direction of flow (by default it is top down)
  - [x] Handle `Throw` instruction (requires keeping track of try blocks)
  - [x] Documentation
  - [x] Prevent node name collisions (functions with the same name)

2 years ago

1 Commits (4aebe39e1503ce8667706cd83ec4180e94e351d2)