Lazily initialize fast_sqrt() and pass an Isolate parameter to it

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); }
 
 UnaryMathFunctionWithIsolate CreateExpFunction(Isolate* isolate) {
-  return x87_std_exp;
+  return nullptr;
 }
 
 
-UnaryMathFunction CreateSqrtFunction() {
+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 == NULL) return &std::sqrt;
+  if (buffer == nullptr) return nullptr;
 
-  MacroAssembler masm(NULL, buffer, static_cast<int>(actual_size),
+  MacroAssembler masm(isolate, buffer, static_cast<int>(actual_size),
                       CodeObjectRequired::kNo);
   // Load double input into registers.
   __ fld_d(MemOperand(esp, 4));
   __ X87SetFPUCW(0x027F);
   __ fsqrt();
   __ X87SetFPUCW(0x037F);
   __ Ret();
 
   CodeDesc desc;
   masm.GetCode(&desc);
   DCHECK(!RelocInfo::RequiresRelocation(desc));
 
-  Assembler::FlushICacheWithoutIsolate(buffer, actual_size);
+  Assembler::FlushICache(isolate, buffer, actual_size);
   base::OS::ProtectCode(buffer, actual_size);
-  return FUNCTION_CAST<UnaryMathFunction>(buffer);
+  return FUNCTION_CAST<UnaryMathFunctionWithIsolate>(buffer);
 }
 
 
 // Helper functions for CreateMemMoveFunction.
 #undef __
 #define __ ACCESS_MASM(masm)
 
 enum Direction { FORWARD, BACKWARD };
 enum Alignment { MOVE_ALIGNED, MOVE_UNALIGNED };
 
@@ skipping 568 matching lines @@
     CodePatcher patcher(sequence, young_length);
     patcher.masm()->call(stub->instruction_start(), RelocInfo::NONE32);
   }
 }
 
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_X87