X87: [turbofan] Introduce Float64Pow and NumberPow operators.

src/x87/code-stubs-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.
 
 #if V8_TARGET_ARCH_X87
 
 #include "src/code-stubs.h"
 #include "src/api-arguments.h"
 #include "src/base/bits.h"
 #include "src/bootstrapper.h"
@@ skipping 252 matching lines @@
   __ mov(scratch, FieldOperand(eax, HeapObject::kMapOffset));
   __ cmp(scratch, factory->heap_number_map());
   __ j(not_equal, non_float);  // argument in eax is not a number -> NaN
 
   // Fall-through: Both operands are numbers.
   __ bind(&done);
 }
 
 
 void MathPowStub::Generate(MacroAssembler* masm) {
-  const Register base = edx;
   const Register scratch = ecx;
-  Label call_runtime;
 
-  // We will call runtime helper function directly.
-  if (exponent_type() == ON_STACK) {
-    // The arguments are still on the stack.
-    __ bind(&call_runtime);
-    __ TailCallRuntime(Runtime::kMathPowRT);
+  // Load the double_exponent into x87 FPU
+  __ fld_d(Operand(esp, 0 * kDoubleSize + 4));
+  // Load the double_base into x87 FPU
+  __ fld_d(Operand(esp, 1 * kDoubleSize + 4));
 
-    // The stub is called from non-optimized code, which expects the result
-    // as heap number in exponent.
-    __ AllocateHeapNumber(eax, scratch, base, &call_runtime);
-    __ fstp_d(FieldOperand(eax, HeapNumber::kValueOffset));
-    __ ret(2 * kPointerSize);
-  } else {
-    // Currently it's only called from full-compiler and exponent type is
-    // ON_STACK.
-    UNIMPLEMENTED();
+  // Call ieee754 runtime directly.
+  {
+    AllowExternalCallThatCantCauseGC scope(masm);
+    __ PrepareCallCFunction(4, scratch);
+    // Put the double_base parameter in call stack
+    __ fstp_d(Operand(esp, 0 * kDoubleSize));
+    // Put the double_exponent parameter in call stack
+    __ fstp_d(Operand(esp, 1 * kDoubleSize));
+    __ CallCFunction(ExternalReference::power_double_double_function(isolate()),
+                     4);
   }
+  // Return value is in st(0) on ia32.
+  __ ret(0);
 }
 
 
 void FunctionPrototypeStub::Generate(MacroAssembler* masm) {
   Label miss;
   Register receiver = LoadDescriptor::ReceiverRegister();
   // With careful management, we won't have to save slot and vector on
   // the stack. Simply handle the possibly missing case first.
   // TODO(mvstanton): this code can be more efficient.
   __ cmp(FieldOperand(receiver, JSFunction::kPrototypeOrInitialMapOffset),
@@ skipping 4985 matching lines @@
                            kStackUnwindSpace, nullptr, return_value_operand,
                            NULL);
 }
 
 #undef __
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_X87