[stubs] Port LoadIndexedStringStub to CSA

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 8568091ce3e9f99657adab793c61e126c6a8c534..b0578740bfe2d819e29f44991817ee956c825f9d 100644
--- a/src/s390/code-stubs-s390.cc
+++ b/src/s390/code-stubs-s390.cc
@@ -1234,37 +1234,6 @@ void FunctionPrototypeStub::Generate(MacroAssembler* masm) {
       masm, PropertyAccessCompiler::MissBuiltin(Code::LOAD_IC));
 }
 
-void LoadIndexedStringStub::Generate(MacroAssembler* masm) {
-  // Return address is in lr.
-  Label miss;
-
-  Register receiver = LoadDescriptor::ReceiverRegister();
-  Register index = LoadDescriptor::NameRegister();
-  Register scratch = r7;
-  Register result = r2;
-  DCHECK(!scratch.is(receiver) && !scratch.is(index));
-  DCHECK(!scratch.is(LoadWithVectorDescriptor::VectorRegister()) &&
-         result.is(LoadWithVectorDescriptor::SlotRegister()));
-
-  // StringCharAtGenerator doesn't use the result register until it's passed
-  // the different miss possibilities. If it did, we would have a conflict
-  // when FLAG_vector_ics is true.
-  StringCharAtGenerator char_at_generator(receiver, index, scratch, result,
-                                          &miss,  // When not a string.
-                                          &miss,  // When not a number.
-                                          &miss,  // When index out of range.
-                                          RECEIVER_IS_STRING);
-  char_at_generator.GenerateFast(masm);
-  __ Ret();
-
-  StubRuntimeCallHelper call_helper;
-  char_at_generator.GenerateSlow(masm, PART_OF_IC_HANDLER, call_helper);
-
-  __ bind(&miss);
-  PropertyAccessCompiler::TailCallBuiltin(
-      masm, PropertyAccessCompiler::MissBuiltin(Code::KEYED_LOAD_IC));
-}
-
 void RegExpExecStub::Generate(MacroAssembler* masm) {
 // Just jump directly to runtime if native RegExp is not selected at compile
 // time or if regexp entry in generated code is turned off runtime switch or
@@ -1945,44 +1914,6 @@ void StringCharCodeAtGenerator::GenerateSlow(
   __ Abort(kUnexpectedFallthroughFromCharCodeAtSlowCase);
 }
 
-// -------------------------------------------------------------------------
-// StringCharFromCodeGenerator
-
-void StringCharFromCodeGenerator::GenerateFast(MacroAssembler* masm) {
-  // Fast case of Heap::LookupSingleCharacterStringFromCode.
-  DCHECK(base::bits::IsPowerOfTwo32(String::kMaxOneByteCharCodeU + 1));
-  __ LoadSmiLiteral(r0, Smi::FromInt(~String::kMaxOneByteCharCodeU));
-  __ OrP(r0, r0, Operand(kSmiTagMask));
-  __ AndP(r0, code_, r0);
-  __ bne(&slow_case_);
-
-  __ LoadRoot(result_, Heap::kSingleCharacterStringCacheRootIndex);
-  // At this point code register contains smi tagged one-byte char code.
-  __ LoadRR(r0, code_);
-  __ SmiToPtrArrayOffset(code_, code_);
-  __ AddP(result_, code_);
-  __ LoadRR(code_, r0);
-  __ LoadP(result_, FieldMemOperand(result_, FixedArray::kHeaderSize));
-  __ CompareRoot(result_, Heap::kUndefinedValueRootIndex);
-  __ beq(&slow_case_);
-  __ bind(&exit_);
-}
-
-void StringCharFromCodeGenerator::GenerateSlow(
-    MacroAssembler* masm, const RuntimeCallHelper& call_helper) {
-  __ Abort(kUnexpectedFallthroughToCharFromCodeSlowCase);
-
-  __ bind(&slow_case_);
-  call_helper.BeforeCall(masm);
-  __ push(code_);
-  __ CallRuntime(Runtime::kStringCharFromCode);
-  __ Move(result_, r2);
-  call_helper.AfterCall(masm);
-  __ b(&exit_);
-
-  __ Abort(kUnexpectedFallthroughFromCharFromCodeSlowCase);
-}
-
 void StringHelper::GenerateFlatOneByteStringEquals(MacroAssembler* masm,
                                                    Register left,
                                                    Register right,