[builtins] Introduce proper Float64Exp operator.

src/arm/codegen-arm.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/arm/codegen-arm.h"
 
 #if V8_TARGET_ARCH_ARM
 
 #include "src/arm/simulator-arm.h"
 #include "src/codegen.h"
 #include "src/macro-assembler.h"
 
 namespace v8 {
 namespace internal {
 
 
 #define __ masm.
 
-
-#if defined(USE_SIMULATOR)
-byte* fast_exp_arm_machine_code = nullptr;
-double fast_exp_simulator(double x, Isolate* isolate) {
-  return Simulator::current(isolate)
-      ->CallFPReturnsDouble(fast_exp_arm_machine_code, x, 0);
-}
-#endif
-
-
-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);
-
-  {
-    DwVfpRegister input = d0;
-    DwVfpRegister result = d1;
-    DwVfpRegister double_scratch1 = d2;
-    DwVfpRegister double_scratch2 = d3;
-    Register temp1 = r4;
-    Register temp2 = r5;
-    Register temp3 = r6;
-
-    if (masm.use_eabi_hardfloat()) {
-      // Input value is in d0 anyway, nothing to do.
-    } else {
-      __ vmov(input, r0, r1);
-    }
-    __ Push(temp3, temp2, temp1);
-    MathExpGenerator::EmitMathExp(
-        &masm, input, result, double_scratch1, double_scratch2,
-        temp1, temp2, temp3);
-    __ Pop(temp3, temp2, temp1);
-    if (masm.use_eabi_hardfloat()) {
-      __ vmov(d0, result);
-    } else {
-      __ vmov(r0, r1, result);
-    }
-    __ Ret();
-  }
-
-  CodeDesc desc;
-  masm.GetCode(&desc);
-  DCHECK(!RelocInfo::RequiresRelocation(desc));
-
-  Assembler::FlushICache(isolate, buffer, actual_size);
-  base::OS::ProtectCode(buffer, actual_size);
-
-#if !defined(USE_SIMULATOR)
-  return FUNCTION_CAST<UnaryMathFunctionWithIsolate>(buffer);
-#else
-  fast_exp_arm_machine_code = buffer;
-  return &fast_exp_simulator;
-#endif
-}
-
 #if defined(V8_HOST_ARCH_ARM)
 MemCopyUint8Function CreateMemCopyUint8Function(Isolate* isolate,
                                                 MemCopyUint8Function stub) {
 #if defined(USE_SIMULATOR)
   return stub;
 #else
   if (!CpuFeatures::IsSupported(UNALIGNED_ACCESSES)) return stub;
   size_t actual_size;
   byte* buffer =
       static_cast<byte*>(base::OS::Allocate(1 * KB, &actual_size, true));
@@ skipping 696 matching lines @@
   __ b(ne, &one_byte);
   // Two-byte string.
   __ ldrh(result, MemOperand(string, index, LSL, 1));
   __ jmp(&done);
   __ bind(&one_byte);
   // One-byte string.
   __ ldrb(result, MemOperand(string, index));
   __ bind(&done);
 }
 
-
-static MemOperand ExpConstant(int index, Register base) {
-  return MemOperand(base, index * kDoubleSize);
-}
-
-
-void MathExpGenerator::EmitMathExp(MacroAssembler* masm,
-                                   DwVfpRegister input,
-                                   DwVfpRegister result,
-                                   DwVfpRegister double_scratch1,
-                                   DwVfpRegister double_scratch2,
-                                   Register temp1,
-                                   Register temp2,
-                                   Register temp3) {
-  DCHECK(!input.is(result));
-  DCHECK(!input.is(double_scratch1));
-  DCHECK(!input.is(double_scratch2));
-  DCHECK(!result.is(double_scratch1));
-  DCHECK(!result.is(double_scratch2));
-  DCHECK(!double_scratch1.is(double_scratch2));
-  DCHECK(!temp1.is(temp2));
-  DCHECK(!temp1.is(temp3));
-  DCHECK(!temp2.is(temp3));
-  DCHECK(ExternalReference::math_exp_constants(0).address() != NULL);
-  DCHECK(!masm->serializer_enabled());  // External references not serializable.
-
-  Label zero, infinity, done;
-
-  __ mov(temp3, Operand(ExternalReference::math_exp_constants(0)));
-
-  __ vldr(double_scratch1, ExpConstant(0, temp3));
-  __ VFPCompareAndSetFlags(double_scratch1, input);
-  __ b(ge, &zero);
-
-  __ vldr(double_scratch2, ExpConstant(1, temp3));
-  __ VFPCompareAndSetFlags(input, double_scratch2);
-  __ b(ge, &infinity);
-
-  __ vldr(double_scratch1, ExpConstant(3, temp3));
-  __ vldr(result, ExpConstant(4, temp3));
-  __ vmul(double_scratch1, double_scratch1, input);
-  __ vadd(double_scratch1, double_scratch1, result);
-  __ VmovLow(temp2, double_scratch1);
-  __ vsub(double_scratch1, double_scratch1, result);
-  __ vldr(result, ExpConstant(6, temp3));
-  __ vldr(double_scratch2, ExpConstant(5, temp3));
-  __ vmul(double_scratch1, double_scratch1, double_scratch2);
-  __ vsub(double_scratch1, double_scratch1, input);
-  __ vsub(result, result, double_scratch1);
-  __ vmul(double_scratch2, double_scratch1, double_scratch1);
-  __ vmul(result, result, double_scratch2);
-  __ vldr(double_scratch2, ExpConstant(7, temp3));
-  __ vmul(result, result, double_scratch2);
-  __ vsub(result, result, double_scratch1);
-  // Mov 1 in double_scratch2 as math_exp_constants_array[8] == 1.
-  DCHECK(*reinterpret_cast<double*>
-         (ExternalReference::math_exp_constants(8).address()) == 1);
-  __ vmov(double_scratch2, 1);
-  __ vadd(result, result, double_scratch2);
-  __ mov(temp1, Operand(temp2, LSR, 11));
-  __ Ubfx(temp2, temp2, 0, 11);
-  __ add(temp1, temp1, Operand(0x3ff));
-
-  // Must not call ExpConstant() after overwriting temp3!
-  __ mov(temp3, Operand(ExternalReference::math_exp_log_table()));
-  __ add(temp3, temp3, Operand(temp2, LSL, 3));
-  __ ldm(ia, temp3, temp2.bit() | temp3.bit());
-  // The first word is loaded is the lower number register.
-  if (temp2.code() < temp3.code()) {
-    __ orr(temp1, temp3, Operand(temp1, LSL, 20));
-    __ vmov(double_scratch1, temp2, temp1);
-  } else {
-    __ orr(temp1, temp2, Operand(temp1, LSL, 20));
-    __ vmov(double_scratch1, temp3, temp1);
-  }
-  __ vmul(result, result, double_scratch1);
-  __ b(&done);
-
-  __ bind(&zero);
-  __ vmov(result, kDoubleRegZero);
-  __ b(&done);
-
-  __ bind(&infinity);
-  __ vldr(result, ExpConstant(2, temp3));
-
-  __ bind(&done);
-}
-
 #undef __
 
 #ifdef DEBUG
 // add(r0, pc, Operand(-8))
 static const uint32_t kCodeAgePatchFirstInstruction = 0xe24f0008;
 #endif
 
 CodeAgingHelper::CodeAgingHelper(Isolate* isolate) {
   USE(isolate);
   DCHECK(young_sequence_.length() == kNoCodeAgeSequenceLength);
@@ skipping 55 matching lines @@
     patcher.masm()->ldr(pc, MemOperand(pc, -4));
     patcher.masm()->emit_code_stub_address(stub);
   }
 }
 
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_ARM