SILGen: Add test for @cdecl testing generated code and C name

Author: xymus

test/SILGen/cdecl-official.swift

@@ -0,0 +1,55 @@
+// RUN: %empty-directory(%t)
+
+// RUN: %target-swift-emit-silgen %s -module-name cdecl \
+// RUN:   -enable-experimental-feature CDecl > %t/out.sil
+// RUN: %FileCheck %s -input-file %t/out.sil
+
+// REQUIRES: swift_feature_CDecl
+
+// CHECK-LABEL: sil hidden [thunk] [ossa] @pear : $@convention(c)
+// CHECK:         function_ref @$s5cdecl5apple{{[_0-9a-zA-Z]*}}F
+// CHECK-LABEL: sil hidden [ossa] @$s5cdecl5apple{{[_0-9a-zA-Z]*}}F
+@cdecl(pear)
+func apple(_ f: @convention(c) (Int) -> Int) { }
+
+// CHECK-LABEL: sil hidden [ossa] @$s5cdecl16forceCEntryPoint{{[_0-9a-zA-Z]*}}F
+// CHECK:         function_ref @grapefruit : $@convention(c) (Int) -> Int
+// CHECK:         function_ref apple(_:)
+// CHECK:         function_ref @$s5cdecl5appleyyS2iXCF : $@convention(thin) (@convention(c) (Int) -> Int) -> ()
+// FIXME should it be function_ref @apple?
+func forceCEntryPoint() {
+  apple(orange)
+}
+
+// CHECK-LABEL: sil hidden [thunk] [ossa] @grapefruit : $@convention(c)
+// CHECK:         function_ref @$s5cdecl6orange{{[_0-9a-zA-Z]*}}F
+// CHECK-LABEL: sil hidden [ossa] @$s5cdecl6orange{{[_0-9a-zA-Z]*}}F
+@cdecl(grapefruit)
+func orange(_ x: Int) -> Int {
+  return x
+}
+
+// CHECK-LABEL: sil [serialized] [thunk] [ossa] @cauliflower : $@convention(c)
+// CHECK:         function_ref @$s5cdecl8broccoli{{[_0-9a-zA-Z]*}}F
+// CHECK-LABEL: sil [ossa] @$s5cdecl8broccoli{{[_0-9a-zA-Z]*}}F
+// FIXME should it be `sil hidden`?
+@cdecl(cauliflower)
+public func broccoli(_ x: Int) -> Int {
+  return x
+}
+
+// CHECK-LABEL: sil private [thunk] [ossa] @collard_greens : $@convention(c)
+// CHECK:         function_ref @$s5cdecl4kale[[PRIVATE:.*]]
+// CHECK:       sil private [ossa] @$s5cdecl4kale[[PRIVATE:.*]]
+@cdecl(collard_greens)
+private func kale(_ x: Int) -> Int {
+  return x
+}
+
+// CHECK-LABEL: sil private [thunk] [ossa] @defaultName : $@convention(c)
+// CHECK:         function_ref @$s5cdecl11defaultName[[PRIVATE:.*]]
+// CHECK:       sil private [ossa] @$s5cdecl11defaultName[[PRIVATE:.*]]
+@cdecl
+private func defaultName(_ x: Int) -> Int {
+  return x
+}