The test case from rdar://problem/20818064 is now scaling well.

DougGregor · DougGregor · commit 6d8cdaf64caa · 2019-03-02T10:11:33.000-08:00
diff --git a/validation-test/Sema/type_checker_perf/fast/rdar20818064.swift.gyb b/validation-test/Sema/type_checker_perf/fast/rdar20818064.swift.gyb
@@ -1,4 +1,4 @@
-// RUN: %scale-test --invert-result --begin 1 --end 5 --step 1 --select NumLeafScopes %s
+// RUN: %scale-test --begin 1 --end 20 --step 1 --select NumLeafScopes %s
 // REQUIRES: OS=macosx
 // REQUIRES: asserts
 

Original file line number	Diff line number	Diff line change
`@@ -1,4 +1,4 @@`
`1`		`-// RUN: %scale-test --invert-result --begin 1 --end 5 --step 1 --select NumLeafScopes %s`
	`1`	`+// RUN: %scale-test --begin 1 --end 20 --step 1 --select NumLeafScopes %s`
`2`	`2`	`// REQUIRES: OS=macosx`
`3`	`3`	`// REQUIRES: asserts`
`4`	`4`