X87: Make fast_exp take an Isolate* paramter.

src/x87/codegen-x87.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/x87/codegen-x87.h"
 
 #if V8_TARGET_ARCH_X87
 
 #include "src/codegen.h"
 #include "src/heap/heap.h"
@@ skipping 14 matching lines @@
 
 
 void StubRuntimeCallHelper::AfterCall(MacroAssembler* masm) const {
   masm->LeaveFrame(StackFrame::INTERNAL);
   DCHECK(masm->has_frame());
   masm->set_has_frame(false);
 }
 
 
 #define __ masm.
+double x87_std_exp(double x, Isolate* isolate) { return std::exp(x); }
 
-
-UnaryMathFunction CreateExpFunction() {
-  // No SSE2 support
-  return nullptr;
+UnaryMathFunctionWithIsolate CreateExpFunction(Isolate* isolate) {
+  return x87_std_exp;

[jochen (gone - plz use gerrit), 2015/11/25 09:01:37]

the init_fast_exp_function() in codegen.cc already uses std::exp with
CreateExpFunction returns a nullptr

 }
 
 
 UnaryMathFunction CreateSqrtFunction() {
   size_t actual_size;
   // Allocate buffer in executable space.
   byte* buffer =
       static_cast<byte*>(base::OS::Allocate(1 * KB, &actual_size, true));
   if (buffer == NULL) return &std::sqrt;
 
@@ skipping 592 matching lines @@
     CodePatcher patcher(sequence, young_length);
     patcher.masm()->call(stub->instruction_start(), RelocInfo::NONE32);
   }
 }
 
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_X87