Remove INCR const param from try_execute_query.

[nnethercote]

try_execute_query has non-incremental and incremental paths. Currently the non-incr/incr distinction is encoded in two different ways: the INCR const bool param and the dep_node option value. We don't need both -- true is always paired with Some and false is always paired with None. This commit removes INCR.

[nnethercote]

@bors try @rust-timer queue

[rust-bors]

☀️ Try build successful (CI)
Build commit: 2d480f7 (2d480f75b29d4f5ab3e11317e8cc41a4f22102b0, parent: 7db0ab43a7f248268e6460b96a955e3d420b485d)

[rust-timer]

Finished benchmarking commit (2d480f7): 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)	0.3%	[0.2%, 0.5%]	9
Regressions ❌ (secondary)	0.5%	[0.1%, 1.0%]	29
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	0.3%	[0.2%, 0.5%]	9

Max RSS (memory usage)

Results (primary -4.8%, secondary -2.5%)

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)	-	-	0
Improvements ✅ (primary)	-4.8%	[-4.8%, -4.8%]	1
Improvements ✅ (secondary)	-2.5%	[-2.5%, -2.5%]	1
All ❌✅ (primary)	-4.8%	[-4.8%, -4.8%]	1

Cycles

Results (primary 7.3%, secondary -0.7%)

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

	mean	range	count
Regressions ❌ (primary)	9.7%	[5.2%, 15.1%]	4
Regressions ❌ (secondary)	4.3%	[4.3%, 4.3%]	1
Improvements ✅ (primary)	-2.3%	[-2.3%, -2.3%]	1
Improvements ✅ (secondary)	-5.6%	[-5.6%, -5.6%]	1
All ❌✅ (primary)	7.3%	[-2.3%, 15.1%]	5

Binary size

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

Bootstrap: 489.054s -> 487.828s (-0.25%)
Artifact size: 394.23 MiB -> 393.56 MiB (-0.17%)