S390: [stubs] Split ToNumberStub into reusable subparts.

src/s390/code-stubs-s390.cc

 // Copyright 2014 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.
 
 #if V8_TARGET_ARCH_S390
 
 #include "src/code-stubs.h"
 #include "src/api-arguments.h"
 #include "src/base/bits.h"
 #include "src/bootstrapper.h"
@@ skipping 2694 matching lines @@
   StringCharAtGenerator generator(r2, r5, r4, r2, &runtime, &runtime, &runtime,
                                   STRING_INDEX_IS_NUMBER, RECEIVER_IS_STRING);
   generator.GenerateFast(masm);
   __ Drop(3);
   __ Ret();
   generator.SkipSlow(masm, &runtime);
 }
 
 void ToNumberStub::Generate(MacroAssembler* masm) {
   // The ToNumber stub takes one argument in r2.
-  Label not_smi;
-  __ JumpIfNotSmi(r2, &not_smi);
-  __ b(r14);
-  __ bind(&not_smi);
+  STATIC_ASSERT(kSmiTag == 0);
+  __ TestIfSmi(r2);
+  __ Ret(eq);
 
   __ CompareObjectType(r2, r3, r3, HEAP_NUMBER_TYPE);
   // r2: receiver
   // r3: receiver instance type
   Label not_heap_number;
   __ bne(&not_heap_number);
   __ Ret();
   __ bind(&not_heap_number);
 
-  Label not_string, slow_string;
-  __ CmpLogicalP(r3, Operand(FIRST_NONSTRING_TYPE));
-  __ bge(&not_string, Label::kNear);
-  // Check if string has a cached array index.
-  __ LoadlW(r4, FieldMemOperand(r2, String::kHashFieldOffset));
-  __ AndP(r0, r4, Operand(String::kContainsCachedArrayIndexMask));
-  __ bne(&slow_string, Label::kNear);
-  __ IndexFromHash(r4, r2);
-  __ b(r14);
-  __ bind(&slow_string);
-  __ push(r2);  // Push argument.
-  __ TailCallRuntime(Runtime::kStringToNumber);
-  __ bind(&not_string);
+  NonNumberToNumberStub stub(masm->isolate());
+  __ TailCallStub(&stub);
+}
+
+void NonNumberToNumberStub::Generate(MacroAssembler* masm) {
+  // The NonNumberToNumber stub takes one argument in r2.
+  __ AssertNotNumber(r2);
+
+  __ CompareObjectType(r2, r3, r3, FIRST_NONSTRING_TYPE);
+  // r2: receiver
+  // r3: receiver instance type
+  StringToNumberStub stub(masm->isolate());
+  __ TailCallStub(&stub, lt);
 
   Label not_oddball;
   __ CmpP(r3, Operand(ODDBALL_TYPE));
   __ bne(&not_oddball, Label::kNear);
   __ LoadP(r2, FieldMemOperand(r2, Oddball::kToNumberOffset));
   __ b(r14);
   __ bind(&not_oddball);
 
   __ push(r2);  // Push argument.
   __ TailCallRuntime(Runtime::kToNumber);
 }
 
+void StringToNumberStub::Generate(MacroAssembler* masm) {
+  // The StringToNumber stub takes one argument in r2.
+  __ AssertString(r2);
+
+  // Check if string has a cached array index.
+  Label runtime;
+  __ LoadlW(r4, FieldMemOperand(r2, String::kHashFieldOffset));
+  __ And(r0, r4, Operand(String::kContainsCachedArrayIndexMask));
+  __ bne(&runtime);
+  __ IndexFromHash(r4, r2);
+  __ Ret();
+
+  __ bind(&runtime);
+  __ push(r2);  // Push argument.
+  __ TailCallRuntime(Runtime::kStringToNumber);
+}
+
 void ToLengthStub::Generate(MacroAssembler* masm) {
   // The ToLength stub takes one argument in r2.
   Label not_smi;
   __ JumpIfNotSmi(r2, &not_smi);
   STATIC_ASSERT(kSmiTag == 0);
   __ CmpP(r2, Operand::Zero());
   Label positive;
   __ bgt(&positive);
   __ LoadImmP(r2, Operand::Zero());
   __ bind(&positive);
@@ skipping 2951 matching lines @@
   CallApiFunctionAndReturn(masm, api_function_address, thunk_ref,
                            kStackUnwindSpace, NULL, return_value_operand, NULL);
 }
 
 #undef __
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_S390