revert atomics for now

Author: Carl Peto

stdlib/public/core/AtomicInt.swift.gyb

@@ -74,9 +74,6 @@ internal func _swift_stdlib_atomicCompareExchangeStrongInt(
 #elseif _pointerBitWidth(_32)
   let (oldValue, won) = Builtin.cmpxchg_seqcst_seqcst_Int32(
     target._rawValue, expected.pointee._value, desired._value)
-#elseif _pointerBitWidth(_16)
-  let (oldValue, won) = Builtin.cmpxchg_seqcst_seqcst_Int16(
-    target._rawValue, expected.pointee._value, desired._value)
 #else
 #error("Unknown platform")
 #endif
@@ -96,9 +93,6 @@ func _swift_stdlib_atomicLoadInt(
 #elseif _pointerBitWidth(_32)
   let value = Builtin.atomicload_seqcst_Int32(target._rawValue)
   return Int(value)
-#elseif _pointerBitWidth(_16)
-  let value = Builtin.atomicload_seqcst_Int16(target._rawValue)
-  return Int(value)
 #else
 #error("Unknown platform")
 #endif
@@ -112,8 +106,6 @@ internal func _swift_stdlib_atomicStoreInt(
   Builtin.atomicstore_seqcst_Int64(target._rawValue, desired._value)
 #elseif _pointerBitWidth(_32)
   Builtin.atomicstore_seqcst_Int32(target._rawValue, desired._value)
-#elseif _pointerBitWidth(_16)
-  Builtin.atomicstore_seqcst_Int16(target._rawValue, desired._value)
 #else
 #error("Unknown platform")
 #endif
@@ -136,17 +128,13 @@ func _swift_stdlib_atomicFetch${operation}Int(
   let value = _swift_stdlib_atomicFetch${operation}Int32(
     object: rawTarget.assumingMemoryBound(to: Int32.self),
     operand: Int32(operand))
-#elseif _pointerBitWidth(_16)
-  let value = _swift_stdlib_atomicFetch${operation}Int16(
-    object: rawTarget.assumingMemoryBound(to: Int16.self),
-    operand: Int16(operand))
 #else
 #error("Unknown platform")
 #endif
   return Int(value)
 }
 
-%   for bits in [ 16, 32, 64 ]:
+%   for bits in [ 32, 64 ]:
 
 // Warning: no overflow checking.
 @usableFromInline // used by SwiftPrivate._stdlib_AtomicInt