borrowck: Make ConstraintCategory::CallArgument diagnostics pinpoint specific args

[Enselic]

Before this commit, ConstraintCategory::CallArgument diagnostics would point to the entire call expression:

LL |     let b = bar(f, y);
   |             ^^^^^^^^^ argument requires that `'a` must outlive `'b`

This commit changes the diagnostics to point to the specific argument that is causing the lifetime issue:

LL |     let b = bar(f, y);
   |                    ^ argument requires that `'a` must outlive `'b`

Draft

This is just a draft and not ready for review. (Although if someone says "this will never work because of ..." I would like to hear that, of course)

I am currently primarily interested in running perf on this, to get a sense for is this can be made to work. If not, there are hopefully other ways to achieve the same end result.

Dependencies

Note that this PR is (partially) stacked on top of the PR #158623.

[Enselic]

@bors try @rust-timer queue

[rust-bors]

☀️ Try build successful (CI)
Build commit: 59ef33b (59ef33b6576cd200d3050ec6127e05704865762a)
Base parent: 3664b37 (3664b37017c529cad0f0ed259769f15743c21a6a)

[rust-timer]

Finished benchmarking commit (59ef33b): comparison URL.

Overall result: ❌ regressions - please read:

Benchmarking means the PR may be perf-sensitive. It's automatically marked not fit for rolling up. Overriding is possible but disadvised: it risks changing compiler perf.

Next, please: If you can, justify the regressions found in this try perf run in writing along with @rustbot label: +perf-regression-triaged. If not, fix the regressions and do another perf run. Neutral or positive results will clear the label automatically.

@bors rollup=never
@rustbot label: -S-waiting-on-perf +perf-regression

Instruction count

Our most reliable metric. Used to determine the overall result above. However, even this metric can be noisy.

	mean	range	count
Regressions ❌ (primary)	0.2%	[0.2%, 0.3%]	6
Regressions ❌ (secondary)	0.1%	[0.1%, 0.2%]	6
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	0.2%	[0.2%, 0.3%]	6

Max RSS (memory usage)

This perf run didn't have relevant results for this metric.

Cycles

Results (secondary -4.5%)

A less reliable metric. May be of interest, but not used to determine the overall result above.

	mean	range	count
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	2.1%	[2.1%, 2.1%]	1
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-11.1%	[-11.1%, -11.1%]	1
All ❌✅ (primary)	-	-	0

Binary size

Results (primary 0.1%, secondary 0.1%)

A less reliable metric. May be of interest, but not used to determine the overall result above.

	mean	range	count
Regressions ❌ (primary)	0.1%	[0.0%, 0.1%]	59
Regressions ❌ (secondary)	0.1%	[0.0%, 0.1%]	22
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	0.1%	[0.0%, 0.1%]	59

Bootstrap: 487.967s -> 489.278s (0.27%)
Artifact size: 388.37 MiB -> 388.89 MiB (0.14%)

[rust-bors]

☔ The latest upstream changes (presumably #159057) made this pull request unmergeable. Please resolve the merge conflicts by rebasing.

[rustbot]

clippy is developed in its own repository. If possible, consider making this change to rust-lang/rust-clippy instead.

cc @rust-lang/clippy

[Enselic]

Sorry, fat thumbs on a smartphone made me accidentally click the "ready" button...