Revert of [regexp] Remove remainder of native RegExpExecStub

src/s390/code-stubs-s390.cc

Index: src/s390/code-stubs-s390.cc
diff --git a/src/s390/code-stubs-s390.cc b/src/s390/code-stubs-s390.cc
index b66d79b8cbeb976ec563702d1e56ba86d413a82b..15d54751d0a3ef835449722b2e02ca4b9302422c 100644
--- a/src/s390/code-stubs-s390.cc
+++ b/src/s390/code-stubs-s390.cc
@@ -1205,6 +1205,87 @@
   __ b(r14);
 }
 
+void RegExpExecStub::Generate(MacroAssembler* masm) {
+#ifdef V8_INTERPRETED_REGEXP
+  // This case is handled prior to the RegExpExecStub call.
+  __ Abort(kUnexpectedRegExpExecCall);
+#else   // V8_INTERPRETED_REGEXP
+  __ CleanseP(r14);
+
+  // Isolates: note we add an additional parameter here (isolate pointer).
+  const int kRegExpExecuteArguments = 10;
+  const int kParameterRegisters = 5;
+  __ EnterExitFrame(false, kRegExpExecuteArguments - kParameterRegisters);
+
+  // Stack pointer now points to cell where return address is to be written.
+  // Arguments are before that on the stack or in registers.
+
+  // Argument 10 (in stack parameter area): Pass current isolate address.
+  __ mov(r6, Operand(ExternalReference::isolate_address(isolate())));
+  __ StoreP(r6, MemOperand(sp, kStackFrameExtraParamSlot * kPointerSize +
+                                   4 * kPointerSize));
+
+  // Argument 9 is a dummy that reserves the space used for
+  // the return address added by the ExitFrame in native calls.
+  __ mov(r6, Operand::Zero());
+  __ StoreP(r6, MemOperand(sp, kStackFrameExtraParamSlot * kPointerSize +
+                                   3 * kPointerSize));
+
+  // Argument 8: Indicate that this is a direct call from JavaScript.
+  __ mov(r6, Operand(1));
+  __ StoreP(r6, MemOperand(sp, kStackFrameExtraParamSlot * kPointerSize +
+                                   2 * kPointerSize));
+
+  // Argument 7: Start (high end) of backtracking stack memory area.
+  ExternalReference address_of_regexp_stack_memory_address =
+      ExternalReference::address_of_regexp_stack_memory_address(isolate());
+  ExternalReference address_of_regexp_stack_memory_size =
+      ExternalReference::address_of_regexp_stack_memory_size(isolate());
+  __ mov(r6, Operand(address_of_regexp_stack_memory_address));
+  __ LoadP(r6, MemOperand(r6, 0));
+  __ mov(r1, Operand(address_of_regexp_stack_memory_size));
+  __ LoadP(r1, MemOperand(r1, 0));
+  __ AddP(r6, r1);
+  __ StoreP(r6, MemOperand(sp, kStackFrameExtraParamSlot * kPointerSize +
+                                   1 * kPointerSize));
+
+  // Argument 6: Set the number of capture registers to zero to force
+  // global egexps to behave as non-global.  This does not affect non-global
+  // regexps.
+  __ mov(r6, Operand::Zero());
+  __ StoreP(r6, MemOperand(sp, kStackFrameExtraParamSlot * kPointerSize +
+                                   0 * kPointerSize));
+
+  // Argument 5 (r6): static offsets vector buffer.
+  __ mov(
+      r6,
+      Operand(ExternalReference::address_of_static_offsets_vector(isolate())));
+
+  // Argument 4, r5: End of string data
+  // Argument 3, r4: Start of string data
+  CHECK(r5.is(RegExpExecDescriptor::StringEndRegister()));
+  CHECK(r4.is(RegExpExecDescriptor::StringStartRegister()));
+
+  // Argument 2 (r3): Previous index.
+  CHECK(r3.is(RegExpExecDescriptor::LastIndexRegister()));
+
+  // Argument 1 (r2): Subject string.
+  CHECK(r2.is(RegExpExecDescriptor::StringRegister()));
+
+  // Locate the code entry and call it.
+  Register code_reg = RegExpExecDescriptor::CodeRegister();
+  __ AddP(code_reg, Operand(Code::kHeaderSize - kHeapObjectTag));
+
+  DirectCEntryStub stub(isolate());
+  stub.GenerateCall(masm, code_reg);
+
+  __ LeaveExitFrame(false, no_reg, true);
+
+  // Return the smi-tagged result.
+  __ SmiTag(r2);
+  __ Ret();
+#endif  // V8_INTERPRETED_REGEXP
+}
 
 static void CallStubInRecordCallTarget(MacroAssembler* masm, CodeStub* stub) {
   // r2 : number of arguments to the construct function