Revert "[Type checker] Represent "initializable" let instance property references as lvalues"

This reverts commit cc4ab6a.

Author: DougGregor

lib/Sema/CSApply.cpp

@@ -1716,24 +1716,10 @@ namespace {
       // For properties, build member references.
       if (auto *varDecl = dyn_cast<VarDecl>(member)) {
         // \returns result of the given function type
-        bool loadImmediately = false;
-        auto resultType = [&loadImmediately](Type fnTy) -> Type {
-          Type resultTy = fnTy->castTo<FunctionType>()->getResult();
-          if (loadImmediately)
-            return LValueType::get(resultTy);
-          return resultTy;
+        auto resultType = [](Type fnTy) -> Type {
+          return fnTy->castTo<FunctionType>()->getResult();
         };
 
-        // If we have an instance property that's treated as an rvalue
-        // but allows assignment (for initialization) in the current
-        // context, treat it as an rvalue that we immediately load.
-        // This is the AST that's expected by SILGen.
-        if (baseIsInstance && !resultType(refTy)->hasLValueType() &&
-            varDecl->mutability(dc, dyn_cast<DeclRefExpr>(base))
-                == StorageMutability::Initializable) {
-          loadImmediately = true;
-        }
-
         if (isUnboundInstanceMember) {
           assert(memberLocator.getBaseLocator() &&
                  cs.UnevaluatedRootExprs.count(
@@ -1779,12 +1765,6 @@ namespace {
                 result, conversionTy));
           }
         }
-
-        // If we need to load, do so now.
-        if (loadImmediately) {
-          result = cs.addImplicitLoadExpr(result);
-        }
-
         return forceUnwrapIfExpected(result, memberLocator);
       }
 

test/SILOptimizer/definite_init_value_types_diagnostics.swift

@@ -78,16 +78,3 @@ struct AddressStruct {
     self = AddressStruct()
   } // expected-error {{return from initializer without initializing all stored properties}}
 }
-
-// Old versions of swift-syntax have this logical use-before-definition; make
-// sure we keep it working.
-struct InitLogicalUseBeforeDef {
-  let offset: UInt16
-
-  init?(value: Int) {
-    if value > type(of: self.offset).max {
-      return nil
-    }
-    offset = UInt16(value)
-  }
-}