Revert removal of checker caching / #1572

[turbolent]

Until we have #1570, let us at least remove the spurious errors which are reported at the moment, but reverting the removal of the checker caching: It is important to return the same checker for a location, as the checker performs type equality checks by Go pointer – returning different instances for the same logical types results in confusing errors.

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• Targeted PR against master branch
• Linked to Github issue with discussion and accepted design OR link to spec that describes this work
• Code follows the standards mentioned here
• Updated relevant documentation
• Re-reviewed Files changed in the Github PR explorer
• Added appropriate labels

[codecov]

Codecov Report

Merging #1628 (6c9df2a) into master (f615bea) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #1628   +/-   ##
=======================================
  Coverage   74.73%   74.73%           
=======================================
  Files         288      288           
  Lines       55340    55340           
=======================================
  Hits        41357    41357           
  Misses      12489    12489           
  Partials     1494     1494           

Flag	Coverage Δ
unittests	74.73% <ø> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
runtime/sema/simple_type.go	92.30% <0.00%> (-3.85%)	⬇️
runtime/interpreter/storage.go	72.78% <0.00%> (+1.36%)	⬆️

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[github-actions]

Cadence Benchstat comparison

This branch with compared with the base branch onflow:master commit f615bea
The command for i in {1..N}; do go test ./... -run=XXX -bench=. -shuffle=on; done was used.
Bench tests were run a total of 7 times on each branch.

Results

	old.txt	new.txt
	time/op		delta
NewInterpreter/new_sub-interpreter-2	2.22µs ± 1%	2.29µs ± 7%	+3.27%	(p=0.042 n=7+7)
RuntimeFungibleTokenTransfer-2	1.28ms ±22%	1.32ms ±26%	~	(p=0.620 n=7+7)
RuntimeResourceDictionaryValues-2	6.48ms ± 1%	6.57ms ± 2%	~	(p=0.209 n=7+7)
Transfer-2	84.0ns ± 1%	84.7ns ± 2%	~	(p=0.168 n=6+7)
ParseDeploy/byte_array-2	21.0ms ± 3%	20.8ms ± 2%	~	(p=0.731 n=6+7)
ParseDeploy/decode_hex-2	1.16ms ± 0%	1.16ms ± 1%	~	(p=0.937 n=6+6)
ParseInfix-2	8.44µs ± 1%	8.72µs ± 5%	~	(p=0.181 n=6+7)
ParseArray-2	12.9ms ± 1%	13.0ms ± 4%	~	(p=0.731 n=6+7)
ParseFungibleToken-2	189µs ± 9%	188µs ±10%	~	(p=0.535 n=7+7)
QualifiedIdentifierCreation/One_level-2	2.34ns ± 0%	2.34ns ± 0%	~	(p=0.688 n=6+6)
QualifiedIdentifierCreation/Three_levels-2	141ns ± 3%	140ns ± 3%	~	(p=0.600 n=7+7)
ContractInterfaceFungibleToken-2	39.2µs ± 1%	39.1µs ± 1%	~	(p=0.628 n=7+6)
CheckContractInterfaceFungibleTokenConformance-2	137µs ±11%	134µs ± 5%	~	(p=0.805 n=7+7)
InterpretRecursionFib-2	2.74ms ± 5%	2.72ms ± 2%	~	(p=0.902 n=7+7)
NewInterpreter/new_interpreter-2	1.14µs ± 1%	1.14µs ± 1%	~	(p=0.784 n=7+7)
	alloc/op		delta
RuntimeFungibleTokenTransfer-2	273kB ± 0%	273kB ± 0%	~	(p=0.710 n=7+7)
RuntimeResourceDictionaryValues-2	2.25MB ± 0%	2.25MB ± 0%	~	(p=0.318 n=7+7)
Transfer-2	48.0B ± 0%	48.0B ± 0%	~	(all equal)
QualifiedIdentifierCreation/One_level-2	0.00B	0.00B	~	(all equal)
QualifiedIdentifierCreation/Three_levels-2	64.0B ± 0%	64.0B ± 0%	~	(all equal)
ContractInterfaceFungibleToken-2	26.7kB ± 0%	26.7kB ± 0%	~	(p=1.000 n=7+7)
CheckContractInterfaceFungibleTokenConformance-2	66.3kB ± 0%	66.3kB ± 0%	~	(all equal)
NewInterpreter/new_interpreter-2	848B ± 0%	848B ± 0%	~	(all equal)
NewInterpreter/new_sub-interpreter-2	1.34kB ± 0%	1.34kB ± 0%	~	(all equal)
InterpretRecursionFib-2	1.14MB ± 0%	1.14MB ± 0%	−0.00%	(p=0.021 n=7+7)
	allocs/op		delta
RuntimeFungibleTokenTransfer-2	4.58k ± 0%	4.58k ± 0%	~	(p=1.000 n=7+7)
RuntimeResourceDictionaryValues-2	37.6k ± 0%	37.6k ± 0%	~	(p=0.623 n=7+7)
Transfer-2	1.00 ± 0%	1.00 ± 0%	~	(all equal)
QualifiedIdentifierCreation/One_level-2	0.00	0.00	~	(all equal)
QualifiedIdentifierCreation/Three_levels-2	2.00 ± 0%	2.00 ± 0%	~	(all equal)
ContractInterfaceFungibleToken-2	460 ± 0%	460 ± 0%	~	(all equal)
CheckContractInterfaceFungibleTokenConformance-2	1.07k ± 0%	1.07k ± 0%	~	(all equal)
InterpretRecursionFib-2	23.8k ± 0%	23.8k ± 0%	~	(all equal)
NewInterpreter/new_interpreter-2	13.0 ± 0%	13.0 ± 0%	~	(all equal)
NewInterpreter/new_sub-interpreter-2	40.0 ± 0%	40.0 ± 0%	~	(all equal)

[devbugging]

Thank you, I was working on this now, but it makes sense to just revert first.