[NFC] Flatten conditionals in AddressLowering.

De-nested the expressions in convertBeginApplyWithOpaqueYield, noting
which cases are handled.

Author: nate-chandler

lib/SILOptimizer/Mandatory/AddressLowering.cpp

@@ -2171,31 +2171,34 @@ void ApplyRewriter::convertBeginApplyWithOpaqueYield() {
   for (auto i : indices(oldResults)) {
     auto &oldResult = oldResults[i];
     auto &newResult = newResults[i];
+    if (oldResult.getType().isObject() && newResult.getType().isObject()) {
+      // Handle direct conventions.
+      oldResult.replaceAllUsesWith(&newResult);
+      continue;
+    }
+    if (oldResult.getType().isAddress()) {
+      // Handle inout convention.
+      assert(newResult.getType().isAddress());
+      oldResult.replaceAllUsesWith(&newResult);
+      continue;
+    }
     if (oldResult.getType().isAddressOnly(*pass.function)) {
-      if (!oldResult.getType().isAddress()) {
-        pass.valueStorageMap.setStorageAddress(&oldResult, &newResult);
-        pass.valueStorageMap.getStorage(&oldResult).markRewritten();
-      } else {
-        oldResult.replaceAllUsesWith(&newResult);
-      }
+      // Remap storage when an address-only type is yielded as an opaque value.
+      pass.valueStorageMap.setStorageAddress(&oldResult, &newResult);
+      pass.valueStorageMap.getStorage(&oldResult).markRewritten();
+      continue;
+    }
+    assert(oldResult.getType().isObject());
+    assert(newResult.getType().isAddress());
+    if (oldResult.getOwnershipKind() == OwnershipKind::Guaranteed) {
+      SILValue load =
+          resultBuilder.emitLoadBorrowOperation(callLoc, &newResult);
+      oldResult.replaceAllUsesWith(load);
+      emitEndBorrows(load, pass);
     } else {
-      if (oldResult.getType().isObject() && newResult.getType().isAddress()) {
-        if (oldResult.getOwnershipKind() == OwnershipKind::Guaranteed) {
-          SILValue load =
-              resultBuilder.emitLoadBorrowOperation(callLoc, &newResult);
-          oldResult.replaceAllUsesWith(load);
-          emitEndBorrows(load, pass);
-        } else {
-          auto *load = resultBuilder.createLoad(
-              callLoc, &newResult,
-              newResult.getType().isTrivial(*pass.function)
-                  ? LoadOwnershipQualifier::Trivial
-                  : LoadOwnershipQualifier::Take);
-          oldResult.replaceAllUsesWith(load);
-        }
-      } else {
-        oldResult.replaceAllUsesWith(&newResult);
-      }
+      auto *load = resultBuilder.createTrivialLoadOr(
+          callLoc, &newResult, LoadOwnershipQualifier::Take);
+      oldResult.replaceAllUsesWith(load);
     }
   }
 }

test/SILOptimizer/address_lowering.sil

@@ -1672,6 +1672,22 @@ bb2:
   unwind
 }
 
+// CHECK-LABEL: sil [ossa] @testBeginApplyFYieldDirectOwnedAndAddressOnlyGuaranteed : {{.*}} {
+// CHECK:       {{bb[0-9]+}}([[OUT_ADDR:%[^,]+]] :
+// CHECK:         ([[OWNED_INSTANCE:%[^,]+]], [[ADDR:%[^,]+]], [[TOKEN:%[^,]+]]) = begin_apply
+// CHECK:         destroy_value [[OWNED_INSTANCE]]
+// CHECK:         copy_addr [[ADDR]] to [init] [[OUT_ADDR]]
+// CHECK:         end_apply [[TOKEN]]
+// CHECK-LABEL: } // end sil function 'testBeginApplyFYieldDirectOwnedAndAddressOnlyGuaranteed'
+sil [ossa] @testBeginApplyFYieldDirectOwnedAndAddressOnlyGuaranteed : $@convention(thin) <T> () -> @out T {
+entry:
+  (%klass, %instance, %token) = begin_apply undef<T>() : $@yield_once @convention(thin) <T> () -> (@yields @owned Klass, @yields @in_guaranteed T)
+  destroy_value %klass : $Klass
+  %retval = copy_value %instance : $T
+  end_apply %token
+  return %retval : $T
+}
+
 // CHECK-LABEL: sil hidden [ossa] @testOpaqueYield :
 // CHECK: bb0(%0 : @guaranteed $TestGeneric<T>):
 // CHECK:   [[REF:%.*]] = ref_element_addr %0 : $TestGeneric<T>, #TestGeneric.borrowedGeneric