s390x: implement LoadEntryFromBuiltin and EntryFromBuiltinAsOperand

Change-Id: I0f42cf86182782b5357d905bfdef1874f6efb909
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3437406Reviewed-by: Milad Farazmand <mfarazma@redhat.com>
Commit-Queue: Junliang Yan <junyan@redhat.com>
Cr-Commit-Position: refs/heads/main@{#78928}

src/codegen/s390/macro-assembler-s390.cc

@@ -4732,6 +4732,19 @@ void TurboAssembler::CallBuiltinByIndex(Register builtin_index) {
   Call(builtin_index);
 }
 
+void TurboAssembler::LoadEntryFromBuiltin(Builtin builtin,
+                                          Register destination) {
+  ASM_CODE_COMMENT(this);
+  LoadU64(destination, EntryFromBuiltinAsOperand(builtin));
+}
+
+MemOperand TurboAssembler::EntryFromBuiltinAsOperand(Builtin builtin) {
+  ASM_CODE_COMMENT(this);
+  DCHECK(root_array_available());
+  return MemOperand(kRootRegister,
+                    IsolateData::BuiltinEntrySlotOffset(builtin));
+}
+
 void TurboAssembler::LoadCodeObjectEntry(Register destination,
                                          Register code_object) {
   // Code objects are called differently depending on whether we are generating

src/codegen/s390/macro-assembler-s390.h

@@ -124,6 +124,8 @@ class V8_EXPORT_PRIVATE TurboAssembler : public TurboAssemblerBase {
   // Load the builtin given by the Smi in |builtin_index| into the same
   // register.
   void LoadEntryFromBuiltinIndex(Register builtin_index);
+  void LoadEntryFromBuiltin(Builtin builtin, Register destination);
+  MemOperand EntryFromBuiltinAsOperand(Builtin builtin);
   void LoadCodeObjectEntry(Register destination, Register code_object);
   void CallCodeObject(Register code_object);
   void JumpCodeObject(Register code_object,