[stdlib] Remove unneeded numericCasts

[benrimmington]

Follow-up to: SE-0191

[benrimmington]

Cc: @airspeedswift

[xedin]

Thank you! If nothing else this would make it easier to type-check these expressions without use of a generic function :)

[CodaFi]

@swift-ci test

[CodaFi]

(Not that I expect fireworks here)

@swift-ci benchmark

[swift-ci]

Performance: -O

Regression	OLD	NEW	DELTA	RATIO
ArrayInitFromSlice	378	475	+25.7%	0.80x
String.data.LargeUnicode	112	132	+17.9%	0.85x (?)
ObjectiveCBridgeStubFromArrayOfNSString2	2970	3410	+14.8%	0.87x (?)
String.data.Medium	108	123	+13.9%	0.88x (?)
StringToDataLargeUnicode	3800	4250	+11.8%	0.89x (?)
SortStringsUnicode	2865	3110	+8.6%	0.92x
Improvement	OLD	NEW	DELTA	RATIO
UTF8Decode_InitFromBytes_ascii	338	295	-12.7%	1.15x (?)
Data.hash.Empty	77	71	-7.8%	1.08x (?)
StringHashing_fastPrenormal	1000	930	-7.0%	1.08x
NSStringConversion.MutableCopy.UTF8	868	810	-6.7%	1.07x (?)

Code size: -O

Regression	OLD	NEW	DELTA	RATIO
AngryPhonebook.o	10038	10147	+1.1%	0.99x

Performance: -Osize

Regression	OLD	NEW	DELTA	RATIO
ArrayInitFromSlice	379	470	+24.0%	0.81x
SortStringsUnicode	2930	3180	+8.5%	0.92x (?)
DataAccessBytesMedium	94	102	+8.5%	0.92x (?)
Improvement	OLD	NEW	DELTA	RATIO
FlattenListFlatMap	7711	5852	-24.1%	1.32x (?)
FlattenListLoop	5562	4718	-15.2%	1.18x (?)
DictionaryOfAnyHashableStrings_insert	5670	4858	-14.3%	1.17x
UTF8Decode_InitFromBytes_ascii	340	296	-12.9%	1.15x (?)
DictionaryOfAnyHashableStrings_lookup	4368	3936	-9.9%	1.11x
Data.hash.Empty	74	68	-8.1%	1.09x (?)
StringHashing_fastPrenormal	1010	930	-7.9%	1.09x
UTF8Decode_InitFromBytes_ascii_as_ascii	485	453	-6.6%	1.07x (?)

Code size: -Osize

Regression	OLD	NEW	DELTA	RATIO
AngryPhonebook.o	9497	9609	+1.2%	0.99x

Performance: -Onone

Regression	OLD	NEW	DELTA	RATIO
ArrayInitFromSlice	431	539	+25.1%	0.80x (?)
NSStringConversion.UTF8	2141	2478	+15.7%	0.86x (?)
NSStringConversion.Mutable	2431	2799	+15.1%	0.87x (?)
ObjectiveCBridgeToNSSet	16350	18050	+10.4%	0.91x (?)
CharIndexing_korean_unicodeScalars_Backwards	611160	665520	+8.9%	0.92x (?)
StringToDataLargeUnicode	4550	4950	+8.8%	0.92x (?)
CharIndexing_chinese_unicodeScalars_Backwards	472760	513160	+8.5%	0.92x (?)
EqualSubstringString	48	52	+8.3%	0.92x (?)
CharIndexing_punctuatedJapanese_unicodeScalars_Backwards	106640	115440	+8.3%	0.92x (?)
Dictionary4OfObjectsLegacy	1642	1775	+8.1%	0.93x (?)
ObjectiveCBridgeStubToNSDate2	620	670	+8.1%	0.93x (?)
String.data.LargeUnicode	131	141	+7.6%	0.93x (?)
Improvement	OLD	NEW	DELTA	RATIO
UTF8Decode_InitFromBytes_ascii	352	309	-12.2%	1.14x (?)
StringBuilderWithLongSubstring	3050	2680	-12.1%	1.14x (?)
DictionaryOfAnyHashableStrings_insert	7882	6958	-11.7%	1.13x (?)
StringRemoveDupes	930	832	-10.5%	1.12x
DictionaryOfAnyHashableStrings_lookup	5064	4584	-9.5%	1.10x (?)
ArrayOfPOD	1118	1035	-7.4%	1.08x (?)
Combos	1482	1383	-6.7%	1.07x (?)

Code size: -swiftlibs

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

[CodaFi]

Yup, all noise.

[CodaFi]

Thanks!

⛵️