stdlib: Make ArrayBufferProtocol.init inlinable to facilitate specialization

[aschwaighofer]

SR-9284

[aschwaighofer]

@swift-ci Please smoke test

[aschwaighofer]

@swift-ci Please benchmark

[aschwaighofer]

@swift-ci Please smoke test

[aschwaighofer]

@swift-ci Please benchmark

[milseman]

LGTM

[swift-ci]

Build comment file:

Performance: -O

TEST	OLD	NEW	DELTA	RATIO
Regression
CharacterLiteralsLarge	97	108	+11.3%	0.90x
SuffixSequence	520	568	+9.2%	0.92x
SuffixSequenceLazy	521	567	+8.8%	0.92x
Improvement
COWArrayGuaranteedParameterOverhead	10672	3858	-63.8%	2.77x
Sim2DArray	399	312	-21.8%	1.28x

Code size: -O

TEST	OLD	NEW	DELTA	RATIO
Regression
ArraySetElement.o	1031	1119	+8.5%	0.92x
Sim2DArray.o	1278	1354	+5.9%	0.94x
ArrayInClass.o	1613	1685	+4.5%	0.96x
COWArrayGuaranteedParameterOverhead.o	1175	1227	+4.4%	0.96x
Memset.o	2084	2148	+3.1%	0.97x
XorLoop.o	1969	2028	+3.0%	0.97x
MonteCarloE.o	3324	3396	+2.2%	0.98x
Array2D.o	4232	4303	+1.7%	0.98x
ReversedCollections.o	11147	11275	+1.1%	0.99x
Improvement
Hash.o	39058	33833	-13.4%	1.15x
RC4.o	4715	4115	-12.7%	1.15x
RemoveWhere.o	26375	23463	-11.0%	1.12x
Walsh.o	9148	8436	-7.8%	1.08x
Prims.o	42913	40201	-6.3%	1.07x
PrimsSplit.o	42965	40253	-6.3%	1.07x
RandomShuffle.o	3381	3291	-2.7%	1.03x
DropLast.o	26467	25947	-2.0%	1.02x
Suffix.o	26361	25889	-1.8%	1.02x
SortStrings.o	27936	27544	-1.4%	1.01x
ArraySubscript.o	4028	3972	-1.4%	1.01x
RGBHistogram.o	27588	27292	-1.1%	1.01x
CSVParsing.o	31881	31545	-1.1%	1.01x
Phonebook.o	11660	11544	-1.0%	1.01x

Performance: -Osize

TEST	OLD	NEW	DELTA	RATIO
Regression
DropLastCountableRangeLazy	11	12	+9.1%	0.92x
Improvement
COWArrayGuaranteedParameterOverhead	10819	4319	-60.1%	2.50x
SuffixCountableRangeLazy	12	11	-8.3%	1.09x

Code size: -Osize

TEST	OLD	NEW	DELTA	RATIO
Regression
ArraySetElement.o	1167	1309	+12.2%	0.89x
ArraySubscript.o	3914	4275	+9.2%	0.92x
Sim2DArray.o	1450	1576	+8.7%	0.92x
XorLoop.o	1938	2098	+8.3%	0.92x
ArrayInClass.o	1840	1982	+7.7%	0.93x
Memset.o	1988	2114	+6.3%	0.94x
COWArrayGuaranteedParameterOverhead.o	1387	1467	+5.8%	0.95x
Array2D.o	4379	4629	+5.7%	0.95x
RandomShuffle.o	3419	3513	+2.7%	0.97x
SortIntPyramids.o	12337	12657	+2.6%	0.97x
MonteCarloE.o	3690	3778	+2.4%	0.98x
ReversedCollections.o	11532	11778	+2.1%	0.98x
StaticArray.o	13019	13155	+1.0%	0.99x
Improvement
RemoveWhere.o	24278	23734	-2.2%	1.02x
Hash.o	20575	20223	-1.7%	1.02x
Walsh.o	6140	6052	-1.4%	1.01x

Performance: -Onone

TEST	OLD	NEW	DELTA	RATIO
Regression
Memset	11449	12517	+9.3%	0.91x
Improvement
COWArrayGuaranteedParameterOverhead	15468	8625	-44.2%	1.79x
SubstringFromLongString	12	11	-8.3%	1.09x (?)
SortStrings	3359	3132	-6.8%	1.07x

Code size: -swiftlibs

TEST	OLD	NEW	DELTA	RATIO
Regression
libswiftSwiftOnoneSupport.dylib	159744	163840	+2.6%	0.98x
Improvement
libswiftSwiftPrivateLibcExtras.dylib	24576	20480	-16.7%	1.20x
libswiftModelIO.dylib	45056	40960	-9.1%	1.10x
libswiftFoundation.dylib	1519616	1503232	-1.1%	1.01x

How to read the data

The tables contain differences in performance which are larger than 8% and differences in code size which are larger than 1%.

If you see any unexpected regressions, you should consider fixing the
regressions before you merge the PR.

Noise: Sometimes the performance results (not code size!) contain false
alarms. Unexpected regressions which are marked with '(?)' are probably noise.
If you see regressions which you cannot explain you can try to run the
benchmarks again. If regressions still show up, please consult with the
performance team (@eeckstein).

Hardware Overview

  Model Name: Mac Pro
  Model Identifier: MacPro6,1
  Processor Name: 12-Core Intel Xeon E5
  Processor Speed: 2.7 GHz
  Number of Processors: 1
  Total Number of Cores: 12
  L2 Cache (per Core): 256 KB
  L3 Cache: 30 MB
  Memory: 64 GB

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