Clean up ObjectFlags enum

[ahejlsberg]

This PR cleans up the ObjectFlags enum. Specifically, it organizes the flags such that bit positions are reused to have different meanings in different types. This frees up several bit positions and ensures that no flags use bit positions 30 and above. We previously had a flag with the value 1 << 30, the use of which adversely impacted performance because the VM boxes values in that range.

[Pokute]

Does this break the API? Previously internal IsGenericObjectTypeComputed is visible as ContainsSpread for API, but the users never had to check the typeFlags. This could result in something like a naive AST explorer displaying a union having spread. Pretty rare, but possible.

[sandersn]

@typescript-bot perf test this

[typescript-bot]

Heya @sandersn, I've started to run the perf test suite on this PR at 96ad79c. You can monitor the build here.

Update: The results are in!

[ahejlsberg]

Does this break the API?

Yes, in theory it is a breaking change because a couple of visible flags now require a check of TypeFlags first. That said, ContainsSpread and ObjectRestType are pretty esoteric flags, and I'm almost inclined to just make them private.

[typescript-bot]

@sandersn
The results of the perf run you requested are in!

Here they are:

Comparison Report - master..43732

Metric	master	43732	Delta	Best	Worst
Angular - node (v10.16.3, x64)
Memory used	344,960k (± 0.02%)	344,913k (± 0.03%)	-48k (- 0.01%)	344,785k	345,202k
Parse Time	1.95s (± 0.58%)	1.95s (± 0.55%)	-0.00s (- 0.21%)	1.93s	1.97s
Bind Time	0.84s (± 0.44%)	0.84s (± 0.62%)	+0.00s (+ 0.36%)	0.83s	0.85s
Check Time	5.24s (± 0.40%)	5.21s (± 0.50%)	-0.03s (- 0.57%)	5.17s	5.28s
Emit Time	5.92s (± 0.51%)	5.92s (± 1.01%)	+0.00s (+ 0.03%)	5.84s	6.10s
Total Time	13.95s (± 0.37%)	13.92s (± 0.55%)	-0.03s (- 0.22%)	13.78s	14.08s
Compiler-Unions - node (v10.16.3, x64)
Memory used	203,159k (± 0.04%)	203,093k (± 0.04%)	-66k (- 0.03%)	202,959k	203,346k
Parse Time	0.79s (± 0.95%)	0.79s (± 1.04%)	0.00s ( 0.00%)	0.77s	0.81s
Bind Time	0.53s (± 1.13%)	0.53s (± 1.13%)	0.00s ( 0.00%)	0.51s	0.54s
Check Time	7.58s (± 0.89%)	7.52s (± 0.52%)	-0.06s (- 0.75%)	7.46s	7.63s
Emit Time	2.51s (± 1.16%)	2.49s (± 1.02%)	-0.02s (- 0.87%)	2.42s	2.54s
Total Time	11.41s (± 0.83%)	11.33s (± 0.53%)	-0.08s (- 0.68%)	11.24s	11.49s
Monaco - node (v10.16.3, x64)
Memory used	342,644k (± 0.02%)	342,589k (± 0.02%)	-56k (- 0.02%)	342,475k	342,731k
Parse Time	1.57s (± 0.48%)	1.56s (± 0.64%)	-0.00s (- 0.13%)	1.54s	1.58s
Bind Time	0.74s (± 0.66%)	0.74s (± 0.64%)	-0.00s (- 0.13%)	0.73s	0.75s
Check Time	5.33s (± 0.74%)	5.30s (± 0.26%)	-0.02s (- 0.45%)	5.27s	5.33s
Emit Time	3.02s (± 1.01%)	3.03s (± 0.63%)	+0.00s (+ 0.10%)	2.96s	3.05s
Total Time	10.66s (± 0.47%)	10.63s (± 0.29%)	-0.03s (- 0.29%)	10.56s	10.69s
TFS - node (v10.16.3, x64)
Memory used	304,156k (± 0.01%)	304,213k (± 0.02%)	+57k (+ 0.02%)	304,005k	304,326k
Parse Time	1.22s (± 0.56%)	1.22s (± 0.72%)	+0.00s (+ 0.16%)	1.19s	1.24s
Bind Time	0.71s (± 0.87%)	0.71s (± 0.70%)	-0.00s (- 0.42%)	0.70s	0.72s
Check Time	4.75s (± 0.46%)	4.76s (± 0.43%)	+0.01s (+ 0.21%)	4.69s	4.80s
Emit Time	3.19s (± 0.88%)	3.17s (± 0.93%)	-0.02s (- 0.50%)	3.10s	3.22s
Total Time	9.86s (± 0.38%)	9.85s (± 0.46%)	-0.01s (- 0.06%)	9.73s	9.93s
material-ui - node (v10.16.3, x64)
Memory used	465,277k (± 0.01%)	465,172k (± 0.02%)	-106k (- 0.02%)	464,927k	465,306k
Parse Time	2.02s (± 0.67%)	2.01s (± 0.48%)	-0.01s (- 0.35%)	1.98s	2.03s
Bind Time	0.66s (± 1.32%)	0.66s (± 1.28%)	+0.00s (+ 0.15%)	0.64s	0.68s
Check Time	14.57s (± 0.90%)	14.45s (± 0.66%)	-0.12s (- 0.83%)	14.29s	14.71s
Emit Time	0.00s (± 0.00%)	0.00s (± 0.00%)	0.00s ( NaN%)	0.00s	0.00s
Total Time	17.25s (± 0.83%)	17.13s (± 0.60%)	-0.13s (- 0.72%)	16.95s	17.41s
Angular - node (v12.1.0, x64)
Memory used	322,637k (± 0.02%)	322,646k (± 0.03%)	+8k (+ 0.00%)	322,364k	322,794k
Parse Time	1.95s (± 0.83%)	1.93s (± 0.47%)	-0.02s (- 1.08%)	1.90s	1.95s
Bind Time	0.82s (± 0.73%)	0.82s (± 0.84%)	0.00s ( 0.00%)	0.80s	0.83s
Check Time	5.11s (± 0.42%)	5.10s (± 0.35%)	-0.01s (- 0.18%)	5.06s	5.13s
Emit Time	6.15s (± 0.90%)	6.11s (± 0.56%)	-0.03s (- 0.52%)	6.05s	6.20s
Total Time	14.02s (± 0.51%)	13.96s (± 0.39%)	-0.06s (- 0.45%)	13.82s	14.07s
Compiler-Unions - node (v12.1.0, x64)
Memory used	190,161k (± 0.14%)	190,270k (± 0.22%)	+109k (+ 0.06%)	188,899k	190,812k
Parse Time	0.77s (± 0.52%)	0.77s (± 0.52%)	0.00s ( 0.00%)	0.76s	0.78s
Bind Time	0.53s (± 0.84%)	0.52s (± 0.65%)	-0.01s (- 0.95%)	0.52s	0.53s
Check Time	7.04s (± 0.65%)	7.00s (± 0.97%)	-0.04s (- 0.53%)	6.89s	7.24s
Emit Time	2.48s (± 1.31%)	2.48s (± 1.23%)	-0.01s (- 0.32%)	2.42s	2.54s
Total Time	10.82s (± 0.37%)	10.77s (± 0.64%)	-0.05s (- 0.46%)	10.66s	10.98s
Monaco - node (v12.1.0, x64)
Memory used	324,913k (± 0.06%)	325,028k (± 0.02%)	+115k (+ 0.04%)	324,875k	325,163k
Parse Time	1.54s (± 1.14%)	1.53s (± 0.72%)	-0.01s (- 0.52%)	1.50s	1.56s
Bind Time	0.72s (± 0.86%)	0.72s (± 0.66%)	+0.00s (+ 0.28%)	0.71s	0.73s
Check Time	5.18s (± 0.41%)	5.15s (± 0.54%)	-0.03s (- 0.56%)	5.09s	5.23s
Emit Time	3.10s (± 0.88%)	3.07s (± 0.87%)	-0.03s (- 0.90%)	3.00s	3.12s
Total Time	10.54s (± 0.42%)	10.48s (± 0.35%)	-0.06s (- 0.59%)	10.41s	10.55s
TFS - node (v12.1.0, x64)
Memory used	288,655k (± 0.02%)	288,637k (± 0.02%)	-17k (- 0.01%)	288,489k	288,802k
Parse Time	1.22s (± 0.68%)	1.21s (± 0.92%)	-0.01s (- 0.74%)	1.19s	1.25s
Bind Time	0.69s (± 0.89%)	0.69s (± 0.68%)	-0.00s (- 0.14%)	0.68s	0.70s
Check Time	4.68s (± 0.34%)	4.66s (± 0.47%)	-0.02s (- 0.45%)	4.59s	4.70s
Emit Time	3.24s (± 1.60%)	3.19s (± 0.88%)	-0.05s (- 1.42%)	3.14s	3.27s
Total Time	9.83s (± 0.59%)	9.76s (± 0.50%)	-0.07s (- 0.76%)	9.62s	9.84s
material-ui - node (v12.1.0, x64)
Memory used	443,186k (± 0.07%)	443,292k (± 0.05%)	+105k (+ 0.02%)	442,424k	443,532k
Parse Time	2.04s (± 0.71%)	2.03s (± 0.46%)	-0.01s (- 0.39%)	2.01s	2.05s
Bind Time	0.64s (± 0.96%)	0.65s (± 1.18%)	+0.00s (+ 0.62%)	0.63s	0.66s
Check Time	13.14s (± 1.16%)	13.03s (± 0.66%)	-0.11s (- 0.82%)	12.87s	13.26s
Emit Time	0.00s (± 0.00%)	0.00s (± 0.00%)	0.00s ( NaN%)	0.00s	0.00s
Total Time	15.82s (± 0.95%)	15.71s (± 0.57%)	-0.11s (- 0.69%)	15.53s	15.93s
Angular - node (v14.15.1, x64)
Memory used	321,255k (± 0.01%)	321,278k (± 0.00%)	+23k (+ 0.01%)	321,254k	321,308k
Parse Time	1.93s (± 0.64%)	1.94s (± 0.86%)	+0.01s (+ 0.31%)	1.91s	1.97s
Bind Time	0.87s (± 0.51%)	0.86s (± 0.57%)	-0.00s (- 0.46%)	0.86s	0.88s
Check Time	5.13s (± 0.54%)	5.15s (± 0.55%)	+0.02s (+ 0.39%)	5.10s	5.22s
Emit Time	6.22s (± 0.77%)	6.22s (± 0.63%)	+0.01s (+ 0.13%)	6.17s	6.33s
Total Time	14.15s (± 0.49%)	14.18s (± 0.37%)	+0.03s (+ 0.23%)	14.05s	14.26s
Compiler-Unions - node (v14.15.1, x64)
Memory used	189,572k (± 0.38%)	189,552k (± 0.37%)	-20k (- 0.01%)	189,202k	192,410k
Parse Time	0.80s (± 0.61%)	0.80s (± 0.28%)	-0.00s (- 0.37%)	0.80s	0.81s
Bind Time	0.56s (± 1.10%)	0.56s (± 0.53%)	-0.00s (- 0.18%)	0.55s	0.56s
Check Time	7.14s (± 0.52%)	7.11s (± 0.62%)	-0.03s (- 0.36%)	7.04s	7.22s
Emit Time	2.51s (± 0.76%)	2.49s (± 0.81%)	-0.02s (- 0.64%)	2.44s	2.53s
Total Time	11.00s (± 0.45%)	10.96s (± 0.48%)	-0.04s (- 0.40%)	10.88s	11.09s
Monaco - node (v14.15.1, x64)
Memory used	324,028k (± 0.01%)	324,051k (± 0.01%)	+23k (+ 0.01%)	324,005k	324,089k
Parse Time	1.58s (± 0.95%)	1.57s (± 0.79%)	-0.01s (- 0.51%)	1.55s	1.61s
Bind Time	0.75s (± 0.80%)	0.75s (± 0.66%)	+0.00s (+ 0.13%)	0.74s	0.76s
Check Time	5.12s (± 0.55%)	5.12s (± 0.34%)	-0.00s (- 0.08%)	5.07s	5.15s
Emit Time	3.12s (± 0.50%)	3.14s (± 0.81%)	+0.01s (+ 0.35%)	3.08s	3.18s
Total Time	10.57s (± 0.47%)	10.57s (± 0.40%)	-0.00s (- 0.03%)	10.48s	10.64s
TFS - node (v14.15.1, x64)
Memory used	287,633k (± 0.01%)	287,633k (± 0.01%)	-0k (- 0.00%)	287,582k	287,690k
Parse Time	1.27s (± 1.10%)	1.27s (± 0.83%)	-0.00s (- 0.16%)	1.24s	1.29s
Bind Time	0.71s (± 0.56%)	0.72s (± 0.51%)	+0.00s (+ 0.70%)	0.71s	0.72s
Check Time	4.72s (± 0.41%)	4.72s (± 0.45%)	-0.01s (- 0.13%)	4.67s	4.76s
Emit Time	3.30s (± 0.51%)	3.29s (± 0.76%)	-0.01s (- 0.18%)	3.24s	3.34s
Total Time	10.01s (± 0.29%)	10.00s (± 0.41%)	-0.01s (- 0.12%)	9.92s	10.10s
material-ui - node (v14.15.1, x64)
Memory used	441,460k (± 0.06%)	441,569k (± 0.00%)	+109k (+ 0.02%)	441,543k	441,610k
Parse Time	2.10s (± 0.77%)	2.10s (± 0.69%)	-0.00s (- 0.14%)	2.06s	2.13s
Bind Time	0.70s (± 0.63%)	0.70s (± 0.71%)	-0.01s (- 0.85%)	0.69s	0.71s
Check Time	13.23s (± 0.64%)	13.26s (± 0.74%)	+0.03s (+ 0.26%)	13.06s	13.47s
Emit Time	0.00s (± 0.00%)	0.00s (± 0.00%)	0.00s ( NaN%)	0.00s	0.00s
Total Time	16.03s (± 0.56%)	16.06s (± 0.65%)	+0.03s (+ 0.19%)	15.84s	16.28s

System

Machine Name	ts-ci-ubuntu
Platform	linux 4.4.0-206-generic
Architecture	x64
Available Memory	16 GB
Available Memory	8 GB
CPUs	4 × Intel(R) Core(TM) i7-4770 CPU @ 3.40GHz

Hosts

• node (v10.16.3, x64)
• node (v12.1.0, x64)
• node (v14.15.1, x64)

Scenarios

• Angular - node (v10.16.3, x64)
• Angular - node (v12.1.0, x64)
• Angular - node (v14.15.1, x64)
• Compiler-Unions - node (v10.16.3, x64)
• Compiler-Unions - node (v12.1.0, x64)
• Compiler-Unions - node (v14.15.1, x64)
• Monaco - node (v10.16.3, x64)
• Monaco - node (v12.1.0, x64)
• Monaco - node (v14.15.1, x64)
• TFS - node (v10.16.3, x64)
• TFS - node (v12.1.0, x64)
• TFS - node (v14.15.1, x64)
• material-ui - node (v10.16.3, x64)
• material-ui - node (v12.1.0, x64)
• material-ui - node (v14.15.1, x64)

Benchmark	Name	Iterations
Current	43732	10
Baseline	master	10

Developer Information:

Download Benchmark

[weswigham]

I'm honestly surprised there wasn't anywhere we had to introduce a TypeFlags check.

[sandersn]

I was curious so I ran the perf tests; this doesn't make a performance difference for x64, at least on any of the versions of node we test on.

[ahejlsberg]

@sandersn Yeah, the offending flag is ObjectFlags.IsClassInstanceClone which I think is rarely used. But out of range flags definitely do affect performance, we've seen and measured that previously.