[IRGen] Rewrite dead method test in StdlibUnittest

test/IRGen/Inputs/report_dead_method_call/main.swift

@@ -1,4 +1,8 @@
+// The StdlibUnittest test suite is placed here because it contains
+// expressions that are only allowed at the top level in files named
+// "main.swift".
 
+import StdlibUnittest
 
 @inline(never)
 func testProto(_ c: Container) {
@@ -27,16 +31,22 @@ func testPublicClass(_ c: PublicBase) {
 	c.ghi()
 }
 
-switch Process.argc {
-case 1:
-	callClass()
+let ReportDeadMethodCallTestSuite = TestSuite("ReportDeadMethodCall")
 
-case 2:
-	callProto()
+ReportDeadMethodCallTestSuite.test("Call class") {
+  expectCrashLater()
+  callClass()
+}
 
-case 3:
-	callPublicClass()
+ReportDeadMethodCallTestSuite.test("Call proto") {
+  expectCrashLater()
+  callProto()
+}
 
-default:
-	break
+ReportDeadMethodCallTestSuite.test("Call public class") {
+  expectCrashLater()
+  callPublicClass()
 }
+
+runAllTests()
+

test/IRGen/report_dead_method_call.swift

@@ -1,15 +1,15 @@
-// RUN: rm -rf %t && mkdir -p %t
-// RUN: %target-build-swift %S/Inputs/report_dead_method_call/main.swift %s -O -Xfrontend -disable-access-control -o %t/a.out
-// RUN: %target-run %t/a.out 2> %t/err1.log; FileCheck %s < %t/err1.log
-// RUN: %target-run %t/a.out p1 2> %t/err2.log; FileCheck %s < %t/err2.log
-// RUN: %target-run %t/a.out p1 p2 2> %t/err3.log; FileCheck %s < %t/err3.log
-// REQUIRES: executable_test
-
+// RUN: rm -rf %t
+// RUN: mkdir -p %t
 
-// The -disable-access-control option let us "call" methods, which are removed
-// by dead method elimination.
+// We compile with -O (optimizations) and -disable-access-control (which
+// allows use to "call" methods that are removed by dead code elimination).
+// RUN: %target-build-swift %S/Inputs/report_dead_method_call/main.swift %s -O -Xfrontend -disable-access-control -o %t/report_dead_method_call
 
-// CHECK: fatal error: call of deleted method
+// The private, unused methods are optimized away. The test calls these
+// methods anyway (since it has overridden the access control), so we
+// expect them to produce "fatal error: call of deleted method" when run.
+// RUN: %target-run %t/report_dead_method_call
+// REQUIRES: executable_test
 
 private protocol PrivateProto {
 	func abc()