Revert of [builtins] Introduce proper Float64Exp operator.

src/ia32/codegen-ia32.cc

 // Copyright 2012 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/ia32/codegen-ia32.h"
 
 #if V8_TARGET_ARCH_IA32
 
 #include "src/codegen.h"
 #include "src/heap/heap.h"
@@ skipping 16 matching lines @@
 void StubRuntimeCallHelper::AfterCall(MacroAssembler* masm) const {
   masm->LeaveFrame(StackFrame::INTERNAL);
   DCHECK(masm->has_frame());
   masm->set_has_frame(false);
 }
 
 
 #define __ masm.
 
 
+UnaryMathFunctionWithIsolate CreateExpFunction(Isolate* isolate) {
+  size_t actual_size;
+  byte* buffer =
+      static_cast<byte*>(base::OS::Allocate(1 * KB, &actual_size, true));
+  if (buffer == nullptr) return nullptr;
+  ExternalReference::InitializeMathExpData();
+
+  MacroAssembler masm(isolate, buffer, static_cast<int>(actual_size),
+                      CodeObjectRequired::kNo);
+  // esp[1 * kPointerSize]: raw double input
+  // esp[0 * kPointerSize]: return address
+  {
+    XMMRegister input = xmm1;
+    XMMRegister result = xmm2;
+    __ movsd(input, Operand(esp, 1 * kPointerSize));
+    __ push(eax);
+    __ push(ebx);
+
+    MathExpGenerator::EmitMathExp(&masm, input, result, xmm0, eax, ebx);
+
+    __ pop(ebx);
+    __ pop(eax);
+    __ movsd(Operand(esp, 1 * kPointerSize), result);
+    __ fld_d(Operand(esp, 1 * kPointerSize));
+    __ Ret();
+  }
+
+  CodeDesc desc;
+  masm.GetCode(&desc);
+  DCHECK(!RelocInfo::RequiresRelocation(desc));
+
+  Assembler::FlushICache(isolate, buffer, actual_size);
+  base::OS::ProtectCode(buffer, actual_size);
+  return FUNCTION_CAST<UnaryMathFunctionWithIsolate>(buffer);
+}
+
+
 UnaryMathFunctionWithIsolate CreateSqrtFunction(Isolate* isolate) {
   size_t actual_size;
   // Allocate buffer in executable space.
   byte* buffer =
       static_cast<byte*>(base::OS::Allocate(1 * KB, &actual_size, true));
   if (buffer == nullptr) return nullptr;
   MacroAssembler masm(isolate, buffer, static_cast<int>(actual_size),
                       CodeObjectRequired::kNo);
   // esp[1 * kPointerSize]: raw double input
   // esp[0 * kPointerSize]: return address
@@ skipping 837 matching lines @@
   // One-byte string.
   // Load the byte into the result register.
   __ bind(&one_byte);
   __ movzx_b(result, FieldOperand(string,
                                   index,
                                   times_1,
                                   SeqOneByteString::kHeaderSize));
   __ bind(&done);
 }
 
+
+static Operand ExpConstant(int index) {
+  return Operand::StaticVariable(ExternalReference::math_exp_constants(index));
+}
+
+
+void MathExpGenerator::EmitMathExp(MacroAssembler* masm,
+                                   XMMRegister input,
+                                   XMMRegister result,
+                                   XMMRegister double_scratch,
+                                   Register temp1,
+                                   Register temp2) {
+  DCHECK(!input.is(double_scratch));
+  DCHECK(!input.is(result));
+  DCHECK(!result.is(double_scratch));
+  DCHECK(!temp1.is(temp2));
+  DCHECK(ExternalReference::math_exp_constants(0).address() != NULL);
+  DCHECK(!masm->serializer_enabled());  // External references not serializable.
+
+  Label done;
+
+  __ movsd(double_scratch, ExpConstant(0));
+  __ xorpd(result, result);
+  __ ucomisd(double_scratch, input);
+  __ j(above_equal, &done);
+  __ ucomisd(input, ExpConstant(1));
+  __ movsd(result, ExpConstant(2));
+  __ j(above_equal, &done);
+  __ movsd(double_scratch, ExpConstant(3));
+  __ movsd(result, ExpConstant(4));
+  __ mulsd(double_scratch, input);
+  __ addsd(double_scratch, result);
+  __ movd(temp2, double_scratch);
+  __ subsd(double_scratch, result);
+  __ movsd(result, ExpConstant(6));
+  __ mulsd(double_scratch, ExpConstant(5));
+  __ subsd(double_scratch, input);
+  __ subsd(result, double_scratch);
+  __ movsd(input, double_scratch);
+  __ mulsd(input, double_scratch);
+  __ mulsd(result, input);
+  __ mov(temp1, temp2);
+  __ mulsd(result, ExpConstant(7));
+  __ subsd(result, double_scratch);
+  __ add(temp1, Immediate(0x1ff800));
+  __ addsd(result, ExpConstant(8));
+  __ and_(temp2, Immediate(0x7ff));
+  __ shr(temp1, 11);
+  __ shl(temp1, 20);
+  __ movd(input, temp1);
+  __ pshufd(input, input, static_cast<uint8_t>(0xe1));  // Order: 11 10 00 01
+  __ movsd(double_scratch, Operand::StaticArray(
+      temp2, times_8, ExternalReference::math_exp_log_table()));
+  __ orps(input, double_scratch);
+  __ mulsd(result, input);
+  __ bind(&done);
+}
+
 #undef __
 
 
 CodeAgingHelper::CodeAgingHelper(Isolate* isolate) {
   USE(isolate);
   DCHECK(young_sequence_.length() == kNoCodeAgeSequenceLength);
   CodePatcher patcher(isolate, young_sequence_.start(),
                       young_sequence_.length());
   patcher.masm()->push(ebp);
   patcher.masm()->mov(ebp, esp);
@@ skipping 44 matching lines @@
     CodePatcher patcher(isolate, sequence, young_length);
     patcher.masm()->call(stub->instruction_start(), RelocInfo::NONE32);
   }
 }
 
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_IA32