A64: Implement LPower and extend MathPowStub to support args in registers

src/a64/lithium-a64.cc

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 1786 matching lines @@
     CodeStubInterfaceDescriptor* descriptor =
         info()->code_stub()->GetInterfaceDescriptor(info()->isolate());
     int index = static_cast<int>(instr->index());
     Register reg = DESCRIPTOR_GET_PARAMETER_REGISTER(descriptor, index);
     return DefineFixed(result, reg);
   }
 }
 
 
 LInstruction* LChunkBuilder::DoPower(HPower* instr) {
-  UNIMPLEMENTED_INSTRUCTION();
+  ASSERT(instr->representation().IsDouble());
+  // We call a C function for double power. It can't trigger a GC.
+  // We need to use fixed result register for the call.
+  Representation exponent_type = instr->right()->representation();
+  ASSERT(instr->left()->representation().IsDouble());
+  LOperand* left = UseFixedDouble(instr->left(), d0);
+  LOperand* right = exponent_type.IsDouble() ?
+      UseFixedDouble(instr->right(), d1) :
+      UseFixed(instr->right(), x11);
+  LPower* result = new(zone()) LPower(left, right);
+  return MarkAsCall(DefineFixedDouble(result, d0),
+                    instr,
+                    CAN_DEOPTIMIZE_EAGERLY);
 }
 
 
 LInstruction* LChunkBuilder::DoPushArgument(HPushArgument* instr) {
   ++argument_count_;
   LOperand* argument = UseRegister(instr->argument());
   return new(zone()) LPushArgument(argument);
 }
 
 
@@ skipping 569 matching lines @@
 LInstruction* LChunkBuilder::DoWrapReceiver(HWrapReceiver* instr) {
   LOperand* receiver = UseRegister(instr->receiver());
   LOperand* function = UseRegisterAtStart(instr->function());
   LOperand* temp = TempRegister();
   LWrapReceiver* result = new(zone()) LWrapReceiver(receiver, function, temp);
   return AssignEnvironment(DefineAsRegister(result));
 }
 
 
 } }  // namespace v8::internal