Merge pull request #67418 from drexin/wip-fix-simple-enum-tagoffset

[IRGen] Fix extra inhabitant offset for simple single payload enums w…

Author: drexin

lib/IRGen/TypeLayout.cpp

@@ -2225,7 +2225,7 @@ bool EnumTypeLayoutEntry::buildSinglePayloadRefCountString(
   unsigned extraTagByteCount = 0;
   uint64_t zeroTagValue = 0;
   unsigned xiBitCount = 0;
-  unsigned xiOffset = 0;
+  unsigned xiBitOffset = 0;
   bool isSimple = true;
 
   auto &payloadTI = **cases[0]->getFixedTypeInfo();
@@ -2249,8 +2249,8 @@ bool EnumTypeLayoutEntry::buildSinglePayloadRefCountString(
         isSimple = false;
       } else {
         xiBitCount = std::min(64u, mask.countPopulation());
-        xiOffset = mask.countTrailingZeros();
-        zeroTagValue = lowValue.extractBitsAsZExtValue(xiBitCount, xiOffset);
+        xiBitOffset = mask.countTrailingZeros();
+        zeroTagValue = lowValue.extractBitsAsZExtValue(xiBitCount, xiBitOffset);
       }
     }
   }
@@ -2279,7 +2279,7 @@ bool EnumTypeLayoutEntry::buildSinglePayloadRefCountString(
 
   if (isSimple) {
     B.addSinglePayloadEnumSimple(zeroTagValue, xiTagValues, extraTagByteCount,
-                                 xiBitCount / 8, xiOffset, cases[0]);
+                                 xiBitCount / 8, xiBitOffset / 8, cases[0]);
   } else {
     auto tagFn = createFixedEnumLoadTag(IGM, *this);
     B.addSinglePayloadEnumFN(tagFn, extraTagByteCount, cases[0]);

test/Interpreter/Inputs/layout_string_witnesses_types.swift

@@ -432,6 +432,14 @@ public struct ComplexNesting<A, B, C, D> {
     }
 }
 
+public enum SinglePayloadAnyHashableEnum {
+    case empty0
+    case empty1
+    case empty2
+    case empty3
+    case nonEmpty(AnyHashable)
+}
+
 internal enum InternalEnum {
   case a(Int, AnyObject)
   case b(Int)

test/Interpreter/layout_string_witnesses_static.swift

@@ -464,6 +464,37 @@ func testContainsSinglePayloadSimpleClassEnumEmpty() {
 
 testContainsSinglePayloadSimpleClassEnumEmpty()
 
+func testSinglePayloadAnyHashableEnum() {
+    let ptr = UnsafeMutablePointer<SinglePayloadAnyHashableEnum>.allocate(capacity: 1)
+
+    do {
+        let x = SinglePayloadAnyHashableEnum.empty0
+        testInit(ptr, to: x)
+    }
+
+    do {
+        // CHECK: empty0
+        if case .empty0 = ptr.pointee {
+            print("empty0")
+        }
+
+        let y = SinglePayloadAnyHashableEnum.empty0
+
+        testAssign(ptr, from: y)
+    }
+
+    // CHECK-NEXT: empty0
+    if case .empty0 = ptr.pointee {
+        print("empty0")
+    }
+
+    testDestroy(ptr)
+
+    ptr.deallocate()
+}
+
+testSinglePayloadAnyHashableEnum()
+
 func testMultiPayloadEnum() {
     let ptr = UnsafeMutablePointer<MultiPayloadEnumWrapper>.allocate(capacity: 1)