Revert of [builtins] Introduce proper Float64Exp operator.

src/crankshaft/arm64/lithium-codegen-arm64.cc

 // Copyright 2013 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/crankshaft/arm64/lithium-codegen-arm64.h"
 
 #include "src/arm64/frames-arm64.h"
 #include "src/base/bits.h"
 #include "src/code-factory.h"
 #include "src/code-stubs.h"
@@ skipping 3530 matching lines @@
   __ B(deferred->allocation_entry());
 
   __ Bind(deferred->exit());
   __ Str(result_bits, FieldMemOperand(result, HeapNumber::kValueOffset));
 
   __ Bind(&done);
 }
 
 
 void LCodeGen::DoMathExp(LMathExp* instr) {
-  DCHECK(instr->IsMarkedAsCall());
-  DCHECK(ToDoubleRegister(instr->value()).is(d0));
-  __ CallCFunction(ExternalReference::ieee754_exp_function(isolate()), 0, 1);
-  DCHECK(ToDoubleRegister(instr->result()).Is(d0));
+  DoubleRegister input = ToDoubleRegister(instr->value());
+  DoubleRegister result = ToDoubleRegister(instr->result());
+  DoubleRegister double_temp1 = ToDoubleRegister(instr->double_temp1());
+  DoubleRegister double_temp2 = double_scratch();
+  Register temp1 = ToRegister(instr->temp1());
+  Register temp2 = ToRegister(instr->temp2());
+  Register temp3 = ToRegister(instr->temp3());
+
+  MathExpGenerator::EmitMathExp(masm(), input, result,
+                                double_temp1, double_temp2,
+                                temp1, temp2, temp3);
 }
 
 
 void LCodeGen::DoMathFloorD(LMathFloorD* instr) {
   DoubleRegister input = ToDoubleRegister(instr->value());
   DoubleRegister result = ToDoubleRegister(instr->result());
 
   __ Frintm(result, input);
 }
 
@@ skipping 2167 matching lines @@
   // Index is equal to negated out of object property index plus 1.
   __ Sub(result, result, Operand::UntagSmiAndScale(index, kPointerSizeLog2));
   __ Ldr(result, FieldMemOperand(result,
                                  FixedArray::kHeaderSize - kPointerSize));
   __ Bind(deferred->exit());
   __ Bind(&done);
 }
 
 }  // namespace internal
 }  // namespace v8