Use addresses to represent inout/inout_aliasable when using opaque values

Author: meg-gupta

lib/SILGen/SILGenProlog.cpp

@@ -458,7 +458,11 @@ static void emitCaptureArguments(SILGenFunction &SGF,
     // Non-escaping stored decls are captured as the address of the value.
     auto type = getVarTypeInCaptureContext();
     SILType ty = SGF.getLoweredType(type);
-    if (SGF.SGM.M.useLoweredAddresses()) {
+    auto argConv = SGF.F.getConventions().getSILArgumentConvention(
+        SGF.F.begin()->getNumArguments());
+    bool isInOut = (argConv == SILArgumentConvention::Indirect_Inout ||
+                    argConv == SILArgumentConvention::Indirect_InoutAliasable);
+    if (isInOut || SGF.SGM.M.useLoweredAddresses()) {
       ty = ty.getAddressType();
     }
     SILValue arg = SGF.F.begin()->createFunctionArgument(ty, VD);

test/SILGen/opaque_values_silgen.swift

@@ -367,3 +367,11 @@ extension Array where Element == Int {
     }
   }
 }
+
+// CHECK-LABEL: sil private [ossa] @$s20opaque_values_silgen22anon_read_only_captureyS2iFSiyXEfU_ : $@convention(thin) (@inout_aliasable Int) -> Int {
+// CHECK-LABEL: } // end sil function '$s20opaque_values_silgen22anon_read_only_captureyS2iFSiyXEfU_'
+func anon_read_only_capture(_ x: Int) -> Int {
+  var x = x
+  return ({ x })()
+}
+