Add StringMap, NumberMap, and StringSet data structures

[ghost]

This switches us to using native Maps and Sets where possible.
Since we can't guarantee that the native Map will exist, we instead have StringMap and NumberMap for string-keyed and number-keyed maps, with shims using objects and arrays.
Many remaining uses of the old Map may be better off as StringMap, but I've left alone anything that looks public-facing.
I've also mostly left declarationEmitter and emitter alone. When we merge the transforms branch in we should use the new maps there.

I'd like to assign @rakatyal to this but it looks like he's not yet on the available assignees list.

[yuit]

nit: I think it will be easier to read if you just use StringMap instead of SMap and same as NumberMap for NMap

[ghost]

On that topic, what should we name ObjMap? (The keys aren't objects. The map itself is an object, which is used like a StringMap.)

[weswigham]

NumberKeyedMap, StringKeyedMap, ObjectBackedMap. With good autcomplete, there's no real reason for confusing or ambiguous hungarianesque notation.

[rakatyal]

What's the purpose of singletonMap?

[ghost]

Thought it was neater than new SMap([[symbol.name, symbol]]).

[weswigham]

Nothing about this is like a singleton in the design pattern sense (it's a loaded term), so the name is a bit confusing. createStringKeyedMap would be more straightforward, if you must wrap the constructor.

[weswigham]

This appears to sort object type keys (which is causing what should be a transparent change to manifest in our baselines). With this change sort order is now insertion order (which arguably is nice), however this is likely a problem because the polyfills right now don't do the same sorting. (This may surface as node 0.10 failing CI with mismatching baselines once the other bugs are fixed)

[rakatyal]

Should this be isSetEmpty?

[rakatyal]

Could you also please share some numbers on how this effect both memory and performance in the typescript repo and other use cases?

[ghost]

Overall, we get about a 10% reduction of both memory and total time. (We could get even more by changing the emitter to use StringMaps.)

(Note: since file system accesses are cached, I throw away the first run, which has a large I/O read time.)

VSCode

Testing on the latest checkout of Microsoft/vscode:

Constant:

Files:            1120
Lines:          312630
Nodes:         1591307
Identifiers:    496012
Symbols:        417268
Types:          114545
I/O write:       0.00s (--noEmit)
Emit time:       0.00s (--noEmit)

tsc -p src --noEmit --diagnostics:

Memory used:   704300K 679391K 679408K
I/O read:        0.18s 0.22s 0.19s
Parse time:      5.36s 5.58s 5.60s
Bind time:       1.51s 1.70s 1.64s
Check time:     10.44s 10.24s 9.79s
Total time:     17.30s 17.52s 17.02s

node ../TypeScript/built/local/tsc --noEmit --diagnostics -p src:

Memory used:   593708K 589821K 595477K
I/O read:        0.24s 0.19s 0.17s
Parse time:      5.43s 5.21s 5.01s
Bind time:       1.16s 1.25s 1.43s
Check time:      8.46s 8.97s 9.13s
Total time:     15.05s 15.43s 15.57s

Typescript services

Testing on the src/services directory (in this branch):

Files:              43
Lines:           91284
Nodes:          456582
Identifiers:    168783
Symbols:        156627
Types:           31431
I/O read:        0.04s 0.02s 0.03s 0.02s 0.01s 0.02s

tsc -p src/services --noEmit --diagnostics:

Memory used:   243354K 243332K 235689K
Parse time:      0.75s 0.78s 0.77s
Bind time:       0.46s 0.47s 0.46s
Check time:      3.28s 3.19s 3.24s
Total time:      4.49s 4.43s 4.47s

node ./built/local/tsc.js -p src/services --noEmit --diagnostics

Memory used:   216397K 216644K 217180K
Parse time:      0.79s 0.77s 0.84s
Bind time:       0.39s 0.36s 0.39s
Check time:      2.77s 2.73s 2.84s
Total time:      3.95s 3.87s 4.08s

Single file

Just a file with console.log("Hello world!")

Files:               2
Lines:           19010
Nodes:           98062
Identifiers:     35497
Symbols:         94435
Types:           11926

tsc --diagnostics --noEmit a.ts:

Memory used:    89009K 89023K 89243K
I/O read:        0.00s 0.00s 0.00s
Parse time:      0.25s 0.21s 0.21s
Bind time:       0.10s 0.10s 0.08s
Check time:      0.91s 0.99s 0.91s
Total time:      1.26s 1.30s 1.20s

node ../../../TypeScript/built/local/tsc.js --diagnostics --noEmit a.ts:

Memory used:    82048K 81071K 81771K
I/O read:        0.00s 0.00s 0.00s
Parse time:      0.21s 0.20s 0.20s
Bind time:       0.12s 0.09s 0.09s
Check time:      0.76s 0.64s 0.74s
Total time:      1.09s 0.93s 1.02s

Interactive test

What I did:

Go to vscode repo
`code src`
Use file navigator to go to vs/base/browser/ui/actionbar/actionbar.ts
Then type ctrl-t, "getZoomLevel"
View memory in task manager

Then go to settings and change "typescript.tsdk" to point to my local version, close all tabs, and start over.

"C:\\Program Files\\nodejs\\node_modules\\typescript\\lib": 272.2MB

"C:\\Users\\anhans\\work\\TypeScript\\built\\local": 265.7MB

[mhegazy]

@andy-ms what were the numbers if we are using the shims and not the native implementation?

[ghost]

The shims caused an increase in memory due to indirection: the shim was an object pointing to another object in dictionary mode.

With native maps:

Memory used:   611586K
Parse time:      4.88s
Bind time:       1.26s
Check time:      8.22s
Total time:     14.36s

Memory used:   613703K
Parse time:      5.01s
Bind time:       1.26s
Check time:      8.45s
Total time:     14.72s

Memory used:   613734K
Parse time:      4.99s
Bind time:       1.27s
Check time:      8.17s
Total time:     14.43s

With the shims always used:

Memory used:   835746K
Parse time:      5.34s
Bind time:       1.63s
Check time:     11.22s
Total time:     18.19s

Memory used:   820061K
Parse time:      5.40s
Bind time:       1.57s
Check time:     11.30s
Total time:     18.28s

Memory used:   830217K
Parse time:      5.41s
Bind time:       1.58s
Check time:     11.22s
Total time:     18.20s

I have created a new PR #11210 which fixes this issue.