[Profiler] Emit increment for property wrapper backing initializers

Previously we were creating a SILProfiler for
such functions, but weren't actually emitting the
increment, leading to missed coverage.

Part of the fix for rdar://99931619

Author: hamishknight

lib/SILGen/SILGen.cpp

@@ -1025,7 +1025,8 @@ void SILGenModule::emitFunctionDefinition(SILDeclRef constant, SILFunction *f) {
     f->createProfiler(wrapperInfo.getInitFromWrappedValue(), constant);
     auto varDC = var->getInnermostDeclContext();
     SILGenFunction SGF(*this, *f, varDC);
-    SGF.emitGeneratorFunction(constant, wrapperInfo.getInitFromWrappedValue());
+    SGF.emitGeneratorFunction(constant, wrapperInfo.getInitFromWrappedValue(),
+                              /*EmitProfilerIncrement*/ true);
     postEmitFunction(constant, f);
     break;
   }

test/Profiler/coverage_property_wrapper_backing.swift

@@ -0,0 +1,37 @@
+// RUN: %target-swift-frontend -Xllvm -sil-full-demangle -profile-generate -profile-coverage-mapping -emit-sorted-sil -emit-sil -module-name coverage_property_wrapper_backing %s | %FileCheck %s
+// RUN: %target-swift-frontend -profile-generate -profile-coverage-mapping -emit-ir %s
+
+@propertyWrapper
+struct Wrapper<T> {
+  var wrappedValue: T
+  init(wrappedValue: T, _ x: Int) {
+    self.wrappedValue = wrappedValue
+  }
+}
+
+// rdar://99931619 – Make sure we emit the profiler increment for the backing
+// initializer.
+
+// CHECK-LABEL: sil hidden @$s33coverage_property_wrapper_backing1SV1iSivpfP : $@convention(thin) (Int) -> Wrapper<Int>
+// CHECK:       increment_profiler_counter 0
+// CHECK:       function_ref @$sSb6randomSbyFZ
+// CHECK:       cond_br {{%[0-9]+}}, [[BB:bb[0-9]]]
+// CHECK:       [[BB]]:
+// CHECK-NEXT:  increment_profiler_counter 1
+
+struct S {
+  // CHECK-LABEL: sil_coverage_map {{.*}} "$s33coverage_property_wrapper_backing1SV1iSivpfP" {{.*}} // property wrapper backing initializer of coverage_property_wrapper_backing.S.i
+  // CHECK-NEXT:  [[@LINE+4]]:4 -> [[@LINE+4]]:30 : 0
+  // CHECK-NEXT:  [[@LINE+3]]:24 -> [[@LINE+3]]:25 : 1
+  // CHECK-NEXT:  [[@LINE+2]]:28 -> [[@LINE+2]]:29 : (0 - 1)
+  // CHECK-NEXT:  }
+  @Wrapper(.random() ? 1 : 2)
+  var i = 3
+  // CHECK-LABEL: sil_coverage_map {{.*}} "$s33coverage_property_wrapper_backing1SV2_i{{.*}}" {{.*}} // variable initialization expression of coverage_property_wrapper_backing.S.(_i in {{.*}}) : coverage_property_wrapper_backing.Wrapper<Swift.Int>
+  // CHECK-NEXT: [[@LINE-2]]:11 -> [[@LINE-2]]:12 : 0
+  // CHECK-NEXT: }
+}
+
+// FIXME(rdar://99962285): This is currently needed to SILGen the property
+// initializer for 'i'.
+_ = S().i