PPC/s390: [Atomics] Make Atomics.exchange a builtin using TF

src/builtins/builtins-sharedarraybuffer.cc

 // Copyright 2016 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/builtins/builtins-utils.h"
 #include "src/builtins/builtins.h"
 #include "src/code-factory.h"
 #include "src/code-stub-assembler.h"
 
 namespace v8 {
@@ skipping 273 matching lines @@
 
   Node* index_integer;
   Node* index_word32 =
       ConvertTaggedAtomicIndexToWord32(&a, index, context, &index_integer);
   Node* array_length_word32 = a.TruncateTaggedToWord32(
       context, a.LoadObjectField(array, JSTypedArray::kLengthOffset));
   ValidateAtomicIndex(&a, index_word32, array_length_word32, context);
 
   Node* value_integer = a.ToInteger(context, value);
 
-#if V8_TARGET_ARCH_MIPS || V8_TARGET_ARCH_MIPS64
+#if V8_TARGET_ARCH_MIPS || V8_TARGET_ARCH_MIPS64 || V8_TARGET_ARCH_PPC64 || \
+    V8_TARGET_ARCH_PPC || V8_TARGET_ARCH_S390 || V8_TARGET_ARCH_S390X
   // Node* index_integer = a.ToInteger(context, index);
   a.Return(a.CallRuntime(Runtime::kAtomicsExchange, context, array,
                          index_integer, value_integer));
 #else
   Node* index_word = a.ChangeUint32ToWord(index_word32);
 
   Node* value_word32 = a.TruncateTaggedToWord32(context, value_integer);
 
   CodeStubAssembler::Label i8(&a), u8(&a), i16(&a), u16(&a), i32(&a), u32(&a),
       other(&a);
@@ skipping 31 matching lines @@
                        a.WordShl(index_word, 2), value_word32)));
 
   a.Bind(&u32);
   a.Return(a.ChangeUint32ToTagged(
       a.AtomicExchange(MachineType::Uint32(), backing_store,
                        a.WordShl(index_word, 2), value_word32)));
 
   // This shouldn't happen, we've already validated the type.
   a.Bind(&other);
   a.Return(a.SmiConstant(0));
-#endif  // V8_TARGET_ARCH_MIPS || V8_TARGET_ARCH_MIPS64
+#endif  // V8_TARGET_ARCH_MIPS || V8_TARGET_ARCH_MIPS64 || V8_TARGET_ARCH_PPC64
+        // || V8_TARGET_ARCH_PPC || V8_TARGET_ARCH_S390 || V8_TARGET_ARCH_S390X
 }
 
 }  // namespace internal
 }  // namespace v8