Derive TyEncodable/TyDecodable in rustc_type_ir

[compiler-errors]

when derive(TyEncodable) or derive(TyDecodable) sees an I type parameter on a struct that has no 'tcx, then parameterize the TyEncoder/TyDecoder's interner over that variable rather than TyCtxt<'tcx>.

Also, emit where clauses for fields rather than generics.

[rustbot]

r? @davidtwco

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[davidtwco]

@bors r+ rollup

[bors]

📌 Commit bee7b58 has been approved by davidtwco

It is now in the queue for this repository.

[bors]

⌛ Testing commit bee7b58 with merge 6bf2fb3...

[bors]

☀️ Test successful - checks-actions
Approved by: davidtwco
Pushing 6bf2fb3 to master...

[rust-timer]

Finished benchmarking commit (6bf2fb3): comparison URL.

Overall result: ❌ regressions - no action needed

@rustbot label: -perf-regression

Instruction count

This is a highly reliable metric that was used to determine the overall result at the top of this comment.

	mean	range	count
Regressions ❌ (primary)	0.3%	[0.3%, 0.3%]	1
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	0.3%	[0.3%, 0.3%]	1

Max RSS (memory usage)

Results

This is a less reliable metric that may be of interest but was not used to determine the overall result at the top of this comment.

	mean	range	count
Regressions ❌ (primary)	0.8%	[0.5%, 1.0%]	2
Regressions ❌ (secondary)	3.7%	[2.7%, 4.6%]	2
Improvements ✅ (primary)	-0.9%	[-1.5%, -0.6%]	3
Improvements ✅ (secondary)	-0.5%	[-0.5%, -0.5%]	1
All ❌✅ (primary)	-0.3%	[-1.5%, 1.0%]	5

Cycles

Results

This is a less reliable metric that may be of interest but was not used to determine the overall result at the top of this comment.

	mean	range	count
Regressions ❌ (primary)	0.6%	[0.6%, 0.7%]	2
Regressions ❌ (secondary)	3.7%	[1.0%, 10.3%]	5
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	0.6%	[0.6%, 0.7%]	2

Binary size

This benchmark run did not return any relevant results for this metric.

Bootstrap: 661.435s -> 665.222s (0.57%)
Artifact size: 308.99 MiB -> 308.99 MiB (0.00%)