Merge pull request #68659 from kubamracek/embedded-ispod

[embedded] Handle thick->thin metatype conversion on IsPOD builtin too

SwiftCompilerSources/Sources/Optimizer/InstructionSimplification/SimplifyBuiltin.swift

@@ -40,8 +40,9 @@ extension BuiltinInst : OnoneSimplifyable {
            .AssignCopyArrayNoAlias,
            .AssignCopyArrayFrontToBack,
            .AssignCopyArrayBackToFront,
-           .AssignTakeArray:
-        optimizeArrayBuiltin(context)
+           .AssignTakeArray,
+           .IsPOD:
+        optimizeFirstArgumentToThinMetatype(context)
       default:
         if let literal = constantFold(context) {
           uses.replaceAll(with: literal, context)
@@ -173,7 +174,7 @@ private extension BuiltinInst {
     context.erase(instruction: self)
   }
   
-  func optimizeArrayBuiltin(_ context: SimplifyContext) {
+  func optimizeFirstArgumentToThinMetatype(_ context: SimplifyContext) {
     guard let metatypeInst = operands[0].value as? MetatypeInst,
           metatypeInst.type.representationOfMetatype(in: parentFunction) == .Thick else {
       return

test/embedded/builtins-misc.swift

@@ -0,0 +1,34 @@
+// RUN: %target-swift-emit-ir %s -parse-stdlib -module-name Swift -enable-experimental-feature Embedded -wmo -target arm64e-apple-none | %FileCheck %s
+
+// REQUIRES: swift_in_compiler
+
+class MyClass {}
+
+struct MyStruct {
+  var c: MyClass
+}
+
+public func foo() -> Builtin.Int1 {
+  return Builtin.ispod(MyStruct.self)
+}
+
+// CHECK:      define {{.*}}i1 @"$ss3fooBi1_yF"()
+// CHECK-NEXT: entry:
+// CHECK-NEXT:   ret i1 false
+// CHECK-NEXT: }
+
+public func bar() -> Builtin.Int1 {
+  var s = MyGenericStruct<MyStruct>()
+  return s.foo()
+}
+
+public struct MyGenericStruct<T> {
+  public func foo() -> Builtin.Int1 {
+    return Builtin.ispod(T.self)
+  }
+}
+
+// CHECK:      define {{.*}}i1 @"$ss15MyGenericStructV3fooBi1_yFs0aC0V_Tg5"()
+// CHECK-NEXT: entry:
+// CHECK-NEXT:   ret i1 false
+// CHECK-NEXT: }