Refactor to support multiple outputs in location summary

runtime/vm/intermediate_language_x64.cc

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/globals.h"  // Needed here to get TARGET_ARCH_X64.
 #if defined(TARGET_ARCH_X64)
 
 #include "vm/intermediate_language.h"
 
 #include "vm/dart_entry.h"
@@ skipping 11 matching lines @@
 
 DECLARE_FLAG(int, optimization_counter_threshold);
 DECLARE_FLAG(bool, propagate_ic_data);
 DECLARE_FLAG(bool, throw_on_javascript_int_overflow);
 DECLARE_FLAG(bool, use_osr);
 
 // Generic summary for call instructions that have all arguments pushed
 // on the stack and return the result in a fixed register RAX.
 LocationSummary* Instruction::MakeCallSummary() {
   LocationSummary* result = new LocationSummary(0, 0, LocationSummary::kCall);
-  result->set_out(Location::RegisterLocation(RAX));
+  result->set_out(0, Location::RegisterLocation(RAX));
   return result;
 }
 
 
 LocationSummary* PushArgumentInstr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 1;
   const intptr_t kNumTemps= 0;
   LocationSummary* locs =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
   locs->set_in(0, Location::AnyOrConstant(value()));
@@ skipping 74 matching lines @@
 // Detect pattern when one value is zero and another is a power of 2.
 static bool IsPowerOfTwoKind(intptr_t v1, intptr_t v2) {
   return (Utils::IsPowerOfTwo(v1) && (v2 == 0)) ||
          (Utils::IsPowerOfTwo(v2) && (v1 == 0));
 }
 
 
 LocationSummary* IfThenElseInstr::MakeLocationSummary(bool opt) const {
   comparison()->InitializeLocationSummary(opt);
   // TODO(vegorov): support byte register constraints in the register allocator.
-  comparison()->locs()->set_out(Location::RegisterLocation(RDX));
+  comparison()->locs()->set_out(0, Location::RegisterLocation(RDX));
   return comparison()->locs();
 }
 
 
 void IfThenElseInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
-  ASSERT(locs()->out().reg() == RDX);
+  ASSERT(locs()->out(0).reg() == RDX);
 
   // Clear upper part of the out register. We are going to use setcc on it
   // which is a byte move.
   __ xorq(RDX, RDX);
 
   // Emit comparison code. This must not overwrite the result register.
   BranchLabels labels = { NULL, NULL, NULL };
   Condition true_condition = comparison()->EmitComparisonCode(compiler, labels);
 
   const bool is_power_of_two_kind = IsPowerOfTwoKind(if_true_, if_false_);
@@ skipping 54 matching lines @@
 LocationSummary* StoreLocalInstr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 1;
   return LocationSummary::Make(kNumInputs,
                                Location::SameAsFirstInput(),
                                LocationSummary::kNoCall);
 }
 
 
 void StoreLocalInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   Register value = locs()->in(0).reg();
-  Register result = locs()->out().reg();
+  Register result = locs()->out(0).reg();
   ASSERT(result == value);  // Assert that register assignment is correct.
   __ movq(Address(RBP, local().index() * kWordSize), value);
 }
 
 
 LocationSummary* ConstantInstr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 0;
   return LocationSummary::Make(kNumInputs,
                                Location::RequiresRegister(),
                                LocationSummary::kNoCall);
 }
 
 
 void ConstantInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   // The register allocator drops constant definitions that have no uses.
-  if (!locs()->out().IsInvalid()) {
-    Register result = locs()->out().reg();
+  if (!locs()->out(0).IsInvalid()) {
+    Register result = locs()->out(0).reg();
     __ LoadObject(result, value(), PP);
   }
 }
 
 
 LocationSummary* AssertAssignableInstr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 3;
   const intptr_t kNumTemps = 0;
   LocationSummary* summary =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kCall);
   summary->set_in(0, Location::RegisterLocation(RAX));  // Value.
   summary->set_in(1, Location::RegisterLocation(RCX));  // Instantiator.
   summary->set_in(2, Location::RegisterLocation(RDX));  // Type arguments.
-  summary->set_out(Location::RegisterLocation(RAX));
+  summary->set_out(0, Location::RegisterLocation(RAX));
   return summary;
 }
 
 
 LocationSummary* AssertBooleanInstr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 1;
   const intptr_t kNumTemps = 0;
   LocationSummary* locs =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kCall);
   locs->set_in(0, Location::RegisterLocation(RAX));
-  locs->set_out(Location::RegisterLocation(RAX));
+  locs->set_out(0, Location::RegisterLocation(RAX));
   return locs;
 }
 
 
 static void EmitAssertBoolean(Register reg,
                               intptr_t token_pos,
                               intptr_t deopt_id,
                               LocationSummary* locs,
                               FlowGraphCompiler* compiler) {
   // Check that the type of the value is allowed in conditional context.
@@ skipping 12 matching lines @@
                                 1,
                                 locs);
   // We should never return here.
   __ int3();
   __ Bind(&done);
 }
 
 
 void AssertBooleanInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   Register obj = locs()->in(0).reg();
-  Register result = locs()->out().reg();
+  Register result = locs()->out(0).reg();
 
   EmitAssertBoolean(obj, token_pos(), deopt_id(), locs(), compiler);
   ASSERT(obj == result);
 }
 
 
 static Condition TokenKindToSmiCondition(Token::Kind kind) {
   switch (kind) {
     case Token::kEQ: return EQUAL;
     case Token::kNE: return NOT_EQUAL;
     case Token::kLT: return LESS;
     case Token::kGT: return GREATER;
     case Token::kLTE: return LESS_EQUAL;
     case Token::kGTE: return GREATER_EQUAL;
     default:
       UNREACHABLE();
       return OVERFLOW;
   }
 }
 
 
 LocationSummary* EqualityCompareInstr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 2;
   if (operation_cid() == kDoubleCid) {
     const intptr_t kNumTemps =  0;
     LocationSummary* locs =
         new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
     locs->set_in(0, Location::RequiresFpuRegister());
     locs->set_in(1, Location::RequiresFpuRegister());
-    locs->set_out(Location::RequiresRegister());
+    locs->set_out(0, Location::RequiresRegister());
     return locs;
   }
   if (operation_cid() == kSmiCid) {
     const intptr_t kNumTemps = 0;
     LocationSummary* locs =
         new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
     locs->set_in(0, Location::RegisterOrConstant(left()));
     // Only one input can be a constant operand. The case of two constant
     // operands should be handled by constant propagation.
     // Only right can be a stack slot.
     locs->set_in(1, locs->in(0).IsConstant()
                         ? Location::RequiresRegister()
                         : Location::RegisterOrConstant(right()));
-    locs->set_out(Location::RequiresRegister());
+    locs->set_out(0, Location::RequiresRegister());
     return locs;
   }
   UNREACHABLE();
   return NULL;
 }
 
 
 static void LoadValueCid(FlowGraphCompiler* compiler,
                          Register value_cid_reg,
                          Register value_reg,
@@ skipping 119 matching lines @@
 
 
 void EqualityCompareInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   ASSERT((kind() == Token::kEQ) || (kind() == Token::kNE));
 
   Label is_true, is_false;
   BranchLabels labels = { &is_true, &is_false, &is_false };
   Condition true_condition = EmitComparisonCode(compiler, labels);
   EmitBranchOnCondition(compiler,  true_condition, labels);
 
-  Register result = locs()->out().reg();
+  Register result = locs()->out(0).reg();
   Label done;
   __ Bind(&is_false);
   __ LoadObject(result, Bool::False(), PP);
   __ jmp(&done);
   __ Bind(&is_true);
   __ LoadObject(result, Bool::True(), PP);
   __ Bind(&done);
 }
 
 
@@ skipping 52 matching lines @@
 
 
 LocationSummary* RelationalOpInstr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 2;
   const intptr_t kNumTemps = 0;
   if (operation_cid() == kDoubleCid) {
     LocationSummary* summary =
         new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
     summary->set_in(0, Location::RequiresFpuRegister());
     summary->set_in(1, Location::RequiresFpuRegister());
-    summary->set_out(Location::RequiresRegister());
+    summary->set_out(0, Location::RequiresRegister());
     return summary;
   }
   ASSERT(operation_cid() == kSmiCid);
   LocationSummary* summary =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
   summary->set_in(0, Location::RegisterOrConstant(left()));
   // Only one input can be a constant operand. The case of two constant
   // operands should be handled by constant propagation.
   summary->set_in(1, summary->in(0).IsConstant()
                          ? Location::RequiresRegister()
                          : Location::RegisterOrConstant(right()));
-  summary->set_out(Location::RequiresRegister());
+  summary->set_out(0, Location::RequiresRegister());
   return summary;
 }
 
 
 Condition RelationalOpInstr::EmitComparisonCode(FlowGraphCompiler* compiler,
                                                 BranchLabels labels) {
   if (operation_cid() == kSmiCid) {
     return EmitSmiComparisonOp(compiler, *locs(), kind(), labels);
   } else {
     ASSERT(operation_cid() == kDoubleCid);
     return EmitDoubleComparisonOp(compiler, *locs(), kind(), labels);
   }
 }
 
 
 void RelationalOpInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   Label is_true, is_false;
   BranchLabels labels = { &is_true, &is_false, &is_false };
   Condition true_condition = EmitComparisonCode(compiler, labels);
   EmitBranchOnCondition(compiler, true_condition, labels);
 
-  Register result = locs()->out().reg();
+  Register result = locs()->out(0).reg();
   Label done;
   __ Bind(&is_false);
   __ LoadObject(result, Bool::False(), PP);
   __ jmp(&done);
   __ Bind(&is_true);
   __ LoadObject(result, Bool::True(), PP);
   __ Bind(&done);
 }
 
 
 void RelationalOpInstr::EmitBranchCode(FlowGraphCompiler* compiler,
                                        BranchInstr* branch) {
   BranchLabels labels = compiler->CreateBranchLabels(branch);
   Condition true_condition = EmitComparisonCode(compiler, labels);
   EmitBranchOnCondition(compiler, true_condition, labels);
 }
 
 
 LocationSummary* NativeCallInstr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 0;
   const intptr_t kNumTemps = 3;
   LocationSummary* locs =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kCall);
   locs->set_temp(0, Location::RegisterLocation(RAX));
   locs->set_temp(1, Location::RegisterLocation(RBX));
   locs->set_temp(2, Location::RegisterLocation(R10));
-  locs->set_out(Location::RegisterLocation(RAX));
+  locs->set_out(0, Location::RegisterLocation(RAX));
   return locs;
 }
 
 
 void NativeCallInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   ASSERT(locs()->temp(0).reg() == RAX);
   ASSERT(locs()->temp(1).reg() == RBX);
   ASSERT(locs()->temp(2).reg() == R10);
-  Register result = locs()->out().reg();
+  Register result = locs()->out(0).reg();
 
   // Push the result place holder initialized to NULL.
   __ PushObject(Object::ZoneHandle(), PP);
   // Pass a pointer to the first argument in RAX.
   if (!function().HasOptionalParameters()) {
     __ leaq(RAX, Address(RBP, (kParamEndSlotFromFp +
                                function().NumParameters()) * kWordSize));
   } else {
     __ leaq(RAX,
             Address(RBP, kFirstLocalSlotFromFp * kWordSize));
@@ skipping 29 matching lines @@
   const intptr_t kNumInputs = 1;
   // TODO(fschneider): Allow immediate operands for the char code.
   return LocationSummary::Make(kNumInputs,
                                Location::RequiresRegister(),
                                LocationSummary::kNoCall);
 }
 
 
 void StringFromCharCodeInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   Register char_code = locs()->in(0).reg();
-  Register result = locs()->out().reg();
+  Register result = locs()->out(0).reg();
   __ LoadImmediate(result,
       Immediate(reinterpret_cast<uword>(Symbols::PredefinedAddress())), PP);
   __ movq(result, Address(result,
                           char_code,
                           TIMES_HALF_WORD_SIZE,  // Char code is a smi.
                           Symbols::kNullCharCodeSymbolOffset * kWordSize));
 }
 
 
 LocationSummary* StringToCharCodeInstr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 1;
   return LocationSummary::Make(kNumInputs,
                                Location::RequiresRegister(),
                                LocationSummary::kNoCall);
 }
 
 
 void StringToCharCodeInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   ASSERT(cid_ == kOneByteStringCid);
   Register str = locs()->in(0).reg();
-  Register result = locs()->out().reg();
+  Register result = locs()->out(0).reg();
   Label is_one, done;
   __ movq(result, FieldAddress(str, String::length_offset()));
   __ cmpq(result, Immediate(Smi::RawValue(1)));
   __ j(EQUAL, &is_one, Assembler::kNearJump);
   __ movq(result, Immediate(Smi::RawValue(-1)));
   __ jmp(&done);
   __ Bind(&is_one);
   __ movzxb(result, FieldAddress(str, OneByteString::data_offset()));
   __ SmiTag(result);
   __ Bind(&done);
 }
 
 
 LocationSummary* StringInterpolateInstr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 1;
   const intptr_t kNumTemps = 0;
   LocationSummary* summary =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kCall);
   summary->set_in(0, Location::RegisterLocation(RAX));
-  summary->set_out(Location::RegisterLocation(RAX));
+  summary->set_out(0, Location::RegisterLocation(RAX));
   return summary;
 }
 
 
 void StringInterpolateInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   Register array = locs()->in(0).reg();
   __ pushq(array);
   const int kNumberOfArguments = 1;
   const Array& kNoArgumentNames = Object::null_array();
   compiler->GenerateStaticCall(deopt_id(),
                                token_pos(),
                                CallFunction(),
                                kNumberOfArguments,
                                kNoArgumentNames,
                                locs());
-  ASSERT(locs()->out().reg() == RAX);
+  ASSERT(locs()->out(0).reg() == RAX);
 }
 
 
 LocationSummary* LoadUntaggedInstr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 1;
   return LocationSummary::Make(kNumInputs,
                                Location::RequiresRegister(),
                                LocationSummary::kNoCall);
 }
 
 
 void LoadUntaggedInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   Register object = locs()->in(0).reg();
-  Register result = locs()->out().reg();
+  Register result = locs()->out(0).reg();
   __ movq(result, FieldAddress(object, offset()));
 }
 
 
 LocationSummary* LoadClassIdInstr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 1;
   return LocationSummary::Make(kNumInputs,
                                Location::RequiresRegister(),
                                LocationSummary::kNoCall);
 }
 
 
 void LoadClassIdInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   Register object = locs()->in(0).reg();
-  Register result = locs()->out().reg();
+  Register result = locs()->out(0).reg();
   Label load, done;
   __ testq(object, Immediate(kSmiTagMask));
   __ j(NOT_ZERO, &load, Assembler::kNearJump);
   __ LoadImmediate(result, Immediate(Smi::RawValue(kSmiCid)), PP);
   __ jmp(&done);
   __ Bind(&load);
   __ LoadClassId(result, object);
   __ SmiTag(result);
   __ Bind(&done);
 }
@@ skipping 83 matching lines @@
   } else {
     locs->set_in(1, CanBeImmediateIndex(index(), class_id())
                       ? Location::Constant(
                           index()->definition()->AsConstant()->value())
                       : Location::RequiresRegister());
   }
   if ((representation() == kUnboxedDouble)    ||
       (representation() == kUnboxedFloat32x4) ||
       (representation() == kUnboxedInt32x4)   ||
       (representation() == kUnboxedFloat64x2)) {
-    locs->set_out(Location::RequiresFpuRegister());
+    locs->set_out(0, Location::RequiresFpuRegister());
   } else {
-    locs->set_out(Location::RequiresRegister());
+    locs->set_out(0, Location::RequiresRegister());
   }
   return locs;
 }
 
 
 void LoadIndexedInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   Register array = locs()->in(0).reg();
   Location index = locs()->in(1);
 
   const bool is_external =
@@ skipping 17 matching lines @@
   }
 
   if ((representation() == kUnboxedDouble)    ||
       (representation() == kUnboxedFloat32x4) ||
       (representation() == kUnboxedInt32x4)   ||
       (representation() == kUnboxedFloat64x2)) {
     if ((index_scale() == 1) && index.IsRegister()) {
       __ SmiUntag(index.reg());
     }
 
-    XmmRegister result = locs()->out().fpu_reg();
+    XmmRegister result = locs()->out(0).fpu_reg();
     if (class_id() == kTypedDataFloat32ArrayCid) {
       // Load single precision float.
       __ movss(result, element_address);
     } else if (class_id() == kTypedDataFloat64ArrayCid) {
       __ movsd(result, element_address);
     } else {
       ASSERT((class_id() == kTypedDataInt32x4ArrayCid)   ||
              (class_id() == kTypedDataFloat32x4ArrayCid) ||
              (class_id() == kTypedDataFloat64x2ArrayCid));
       __ movups(result, element_address);
     }
     return;
   }
 
   if ((index_scale() == 1) && index.IsRegister()) {
     __ SmiUntag(index.reg());
   }
-  Register result = locs()->out().reg();
+  Register result = locs()->out(0).reg();
   switch (class_id()) {
     case kTypedDataInt8ArrayCid:
       __ movsxb(result, element_address);
       __ SmiTag(result);
       break;
     case kTypedDataUint8ArrayCid:
     case kTypedDataUint8ClampedArrayCid:
     case kExternalTypedDataUint8ArrayCid:
     case kExternalTypedDataUint8ClampedArrayCid:
     case kOneByteStringCid:
@@ skipping 581 matching lines @@
       : instruction_(instruction), cls_(cls) { }
 
   virtual void EmitNativeCode(FlowGraphCompiler* compiler) {
     __ Comment("StoreInstanceFieldSlowPath");
     __ Bind(entry_label());
     const Code& stub =
         Code::Handle(StubCode::GetAllocationStubForClass(cls_));
     const ExternalLabel label(cls_.ToCString(), stub.EntryPoint());
 
     LocationSummary* locs = instruction_->locs();
-    locs->live_registers()->Remove(locs->out());
+    locs->live_registers()->Remove(locs->out(0));
 
     compiler->SaveLiveRegisters(locs);
     compiler->GenerateCall(Scanner::kNoSourcePos,  // No token position.
                            &label,
                            PcDescriptors::kOther,
                            locs);
     __ MoveRegister(locs->temp(0).reg(), RAX);
     compiler->RestoreLiveRegisters(locs);
 
     __ jmp(exit_label());
@@ skipping 248 matching lines @@
   __ Bind(&skip_store);
 }
 
 
 LocationSummary* LoadStaticFieldInstr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 1;
   const intptr_t kNumTemps = 0;
   LocationSummary* summary =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
   summary->set_in(0, Location::RequiresRegister());
-  summary->set_out(Location::RequiresRegister());
+  summary->set_out(0, Location::RequiresRegister());
   return summary;
 }
 
 
 // When the parser is building an implicit static getter for optimization,
 // it can generate a function body where deoptimization ids do not line up
 // with the unoptimized code.
 //
 // This is safe only so long as LoadStaticFieldInstr cannot deoptimize.
 void LoadStaticFieldInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   Register field = locs()->in(0).reg();
-  Register result = locs()->out().reg();
+  Register result = locs()->out(0).reg();
   __ movq(result, FieldAddress(field, Field::value_offset()));
 }
 
 
 LocationSummary* StoreStaticFieldInstr::MakeLocationSummary(bool opt) const {
   LocationSummary* locs = new LocationSummary(1, 1, LocationSummary::kNoCall);
   locs->set_in(0, value()->NeedsStoreBuffer() ? Location::WritableRegister()
                                               : Location::RequiresRegister());
   locs->set_temp(0, Location::RequiresRegister());
   return locs;
@@ skipping 16 matching lines @@
 
 
 LocationSummary* InstanceOfInstr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 3;
   const intptr_t kNumTemps = 0;
   LocationSummary* summary =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kCall);
   summary->set_in(0, Location::RegisterLocation(RAX));
   summary->set_in(1, Location::RegisterLocation(RCX));
   summary->set_in(2, Location::RegisterLocation(RDX));
-  summary->set_out(Location::RegisterLocation(RAX));
+  summary->set_out(0, Location::RegisterLocation(RAX));
   return summary;
 }
 
 
 void InstanceOfInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   ASSERT(locs()->in(0).reg() == RAX);  // Value.
   ASSERT(locs()->in(1).reg() == RCX);  // Instantiator.
   ASSERT(locs()->in(2).reg() == RDX);  // Instantiator type arguments.
 
   compiler->GenerateInstanceOf(token_pos(),
                                deopt_id(),
                                type(),
                                negate_result(),
                                locs());
-  ASSERT(locs()->out().reg() == RAX);
+  ASSERT(locs()->out(0).reg() == RAX);
 }
 
 
 LocationSummary* CreateArrayInstr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 2;
   const intptr_t kNumTemps = 0;
   LocationSummary* locs =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kCall);
   locs->set_in(0, Location::RegisterLocation(RBX));
   locs->set_in(1, Location::RegisterLocation(R10));
-  locs->set_out(Location::RegisterLocation(RAX));
+  locs->set_out(0, Location::RegisterLocation(RAX));
   return locs;
 }
 
 
 void CreateArrayInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   // Allocate the array.  R10 = length, RBX = element type.
   ASSERT(locs()->in(0).reg() == RBX);
   ASSERT(locs()->in(1).reg() == R10);
   compiler->GenerateCall(token_pos(),
                          &StubCode::AllocateArrayLabel(),
                          PcDescriptors::kOther,
                          locs());
-  ASSERT(locs()->out().reg() == RAX);
+  ASSERT(locs()->out(0).reg() == RAX);
 }
 
 
 class BoxDoubleSlowPath : public SlowPathCode {
  public:
   explicit BoxDoubleSlowPath(Instruction* instruction)
       : instruction_(instruction) { }
 
   virtual void EmitNativeCode(FlowGraphCompiler* compiler) {
     __ Comment("BoxDoubleSlowPath");
     __ Bind(entry_label());
     const Class& double_class = compiler->double_class();
     const Code& stub =
         Code::Handle(StubCode::GetAllocationStubForClass(double_class));
     const ExternalLabel label(double_class.ToCString(), stub.EntryPoint());
 
     LocationSummary* locs = instruction_->locs();
-    locs->live_registers()->Remove(locs->out());
+    locs->live_registers()->Remove(locs->out(0));
 
     compiler->SaveLiveRegisters(locs);
     compiler->GenerateCall(Scanner::kNoSourcePos,  // No token position.
                            &label,
                            PcDescriptors::kOther,
                            locs);
-    __ MoveRegister(locs->out().reg(), RAX);
+    __ MoveRegister(locs->out(0).reg(), RAX);
     compiler->RestoreLiveRegisters(locs);
 
     __ jmp(exit_label());
   }
 
  private:
   Instruction* instruction_;
 };
 
 
 class BoxFloat32x4SlowPath : public SlowPathCode {
  public:
   explicit BoxFloat32x4SlowPath(Instruction* instruction)
       : instruction_(instruction) { }
 
   virtual void EmitNativeCode(FlowGraphCompiler* compiler) {
     __ Comment("BoxFloat32x4SlowPath");
     __ Bind(entry_label());
     const Class& float32x4_class = compiler->float32x4_class();
     const Code& stub =
         Code::Handle(StubCode::GetAllocationStubForClass(float32x4_class));
     const ExternalLabel label(float32x4_class.ToCString(), stub.EntryPoint());
 
     LocationSummary* locs = instruction_->locs();
-    locs->live_registers()->Remove(locs->out());
+    locs->live_registers()->Remove(locs->out(0));
 
     compiler->SaveLiveRegisters(locs);
     compiler->GenerateCall(Scanner::kNoSourcePos,  // No token position.
                            &label,
                            PcDescriptors::kOther,
                            locs);
-    __ MoveRegister(locs->out().reg(), RAX);
+    __ MoveRegister(locs->out(0).reg(), RAX);
     compiler->RestoreLiveRegisters(locs);
 
     __ jmp(exit_label());
   }
 
  private:
   Instruction* instruction_;
 };
 
 
 class BoxFloat64x2SlowPath : public SlowPathCode {
  public:
   explicit BoxFloat64x2SlowPath(Instruction* instruction)
       : instruction_(instruction) { }
 
   virtual void EmitNativeCode(FlowGraphCompiler* compiler) {
     __ Comment("BoxFloat64x2SlowPath");
     __ Bind(entry_label());
     const Class& float64x2_class = compiler->float64x2_class();
     const Code& stub =
         Code::Handle(StubCode::GetAllocationStubForClass(float64x2_class));
     const ExternalLabel label(float64x2_class.ToCString(), stub.EntryPoint());
 
     LocationSummary* locs = instruction_->locs();
-    locs->live_registers()->Remove(locs->out());
+    locs->live_registers()->Remove(locs->out(0));
 
     compiler->SaveLiveRegisters(locs);
     compiler->GenerateCall(Scanner::kNoSourcePos,  // No token position.
                            &label,
                            PcDescriptors::kOther,
                            locs);
-    __ MoveRegister(locs->out().reg(), RAX);
+    __ MoveRegister(locs->out(0).reg(), RAX);
     compiler->RestoreLiveRegisters(locs);
 
     __ jmp(exit_label());
   }
 
  private:
   Instruction* instruction_;
 };
 
 
 LocationSummary* LoadFieldInstr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 1;
   const intptr_t kNumTemps = 0;
   LocationSummary* locs =
       new LocationSummary(
           kNumInputs, kNumTemps,
           (opt && !IsPotentialUnboxedLoad())
           ? LocationSummary::kNoCall
           : LocationSummary::kCallOnSlowPath);
 
   locs->set_in(0, Location::RequiresRegister());
 
   if (IsUnboxedLoad() && opt) {
     locs->AddTemp(Location::RequiresRegister());
   } else if (IsPotentialUnboxedLoad()) {
     locs->AddTemp(opt ? Location::RequiresFpuRegister()
                       : Location::FpuRegisterLocation(XMM1));
     locs->AddTemp(Location::RequiresRegister());
   }
-  locs->set_out(Location::RequiresRegister());
+  locs->set_out(0, Location::RequiresRegister());
   return locs;
 }
 
 
 void LoadFieldInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   Register instance_reg = locs()->in(0).reg();
   if (IsUnboxedLoad() && compiler->is_optimizing()) {
-    XmmRegister result = locs()->out().fpu_reg();
+    XmmRegister result = locs()->out(0).fpu_reg();
     Register temp = locs()->temp(0).reg();
     __ movq(temp, FieldAddress(instance_reg, offset_in_bytes()));
     intptr_t cid = field()->UnboxedFieldCid();
     switch (cid) {
       case kDoubleCid:
         __ Comment("UnboxedDoubleLoadFieldInstr");
         __ movsd(result, FieldAddress(temp, Double::value_offset()));
         break;
       case kFloat32x4Cid:
         __ Comment("UnboxedFloat32x4LoadFieldInstr");
         __ movups(result, FieldAddress(temp, Float32x4::value_offset()));
         break;
       case kFloat64x2Cid:
         __ Comment("UnboxedFloat64x2LoadFieldInstr");
         __ movups(result, FieldAddress(temp, Float64x2::value_offset()));
         break;
       default:
         UNREACHABLE();
     }
     return;
   }
 
   Label done;
-  Register result = locs()->out().reg();
+  Register result = locs()->out(0).reg();
   if (IsPotentialUnboxedLoad()) {
     Register temp = locs()->temp(1).reg();
     XmmRegister value = locs()->temp(0).fpu_reg();
 
     Label load_pointer;
     Label load_double;
     Label load_float32x4;
     Label load_float64x2;
 
     __ LoadObject(result, Field::ZoneHandle(field()->raw()), PP);
@@ skipping 77 matching lines @@
   __ Bind(&done);
 }
 
 
 LocationSummary* InstantiateTypeInstr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 1;
   const intptr_t kNumTemps = 0;
   LocationSummary* locs =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kCall);
   locs->set_in(0, Location::RegisterLocation(RAX));
-  locs->set_out(Location::RegisterLocation(RAX));
+  locs->set_out(0, Location::RegisterLocation(RAX));
   return locs;
 }
 
 
 void InstantiateTypeInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   Register instantiator_reg = locs()->in(0).reg();
-  Register result_reg = locs()->out().reg();
+  Register result_reg = locs()->out(0).reg();
 
   // 'instantiator_reg' is the instantiator TypeArguments object (or null).
   // A runtime call to instantiate the type is required.
   __ PushObject(Object::ZoneHandle(), PP);  // Make room for the result.
   __ PushObject(type(), PP);
   __ pushq(instantiator_reg);  // Push instantiator type arguments.
   compiler->GenerateRuntimeCall(token_pos(),
                                 deopt_id(),
                                 kInstantiateTypeRuntimeEntry,
                                 2,
                                 locs());
   __ Drop(2);  // Drop instantiator and uninstantiated type.
   __ popq(result_reg);  // Pop instantiated type.
   ASSERT(instantiator_reg == result_reg);
 }
 
 
 LocationSummary* InstantiateTypeArgumentsInstr::MakeLocationSummary(
     bool opt) const {
   const intptr_t kNumInputs = 1;
   const intptr_t kNumTemps = 0;
   LocationSummary* locs =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kCall);
   locs->set_in(0, Location::RegisterLocation(RAX));
-  locs->set_out(Location::RegisterLocation(RAX));
+  locs->set_out(0, Location::RegisterLocation(RAX));
   return locs;
 }
 
 
 void InstantiateTypeArgumentsInstr::EmitNativeCode(
     FlowGraphCompiler* compiler) {
   Register instantiator_reg = locs()->in(0).reg();
-  Register result_reg = locs()->out().reg();
+  Register result_reg = locs()->out(0).reg();
   ASSERT(instantiator_reg == RAX);
   ASSERT(instantiator_reg == result_reg);
 
   // 'instantiator_reg' is the instantiator TypeArguments object (or null).
   ASSERT(!type_arguments().IsUninstantiatedIdentity() &&
          !type_arguments().CanShareInstantiatorTypeArguments(
              instantiator_class()));
   // If the instantiator is null and if the type argument vector
   // instantiated from null becomes a vector of dynamic, then use null as
   // the type arguments.
@@ skipping 42 matching lines @@
   ASSERT(instantiator_reg == result_reg);
 }
 
 
 LocationSummary* AllocateContextInstr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 0;
   const intptr_t kNumTemps = 1;
   LocationSummary* locs =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kCall);
   locs->set_temp(0, Location::RegisterLocation(R10));
-  locs->set_out(Location::RegisterLocation(RAX));
+  locs->set_out(0, Location::RegisterLocation(RAX));
   return locs;
 }
 
 
 void AllocateContextInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   ASSERT(locs()->temp(0).reg() == R10);
-  ASSERT(locs()->out().reg() == RAX);
+  ASSERT(locs()->out(0).reg() == RAX);
 
   __ LoadImmediate(R10, Immediate(num_context_variables()), PP);
   const ExternalLabel label("alloc_context",
                             StubCode::AllocateContextEntryPoint());
   compiler->GenerateCall(token_pos(),
                          &label,
                          PcDescriptors::kOther,
                          locs());
 }
 
 
 LocationSummary* CloneContextInstr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 1;
   const intptr_t kNumTemps = 0;
   LocationSummary* locs =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kCall);
   locs->set_in(0, Location::RegisterLocation(RAX));
-  locs->set_out(Location::RegisterLocation(RAX));
+  locs->set_out(0, Location::RegisterLocation(RAX));
   return locs;
 }
 
 
 void CloneContextInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   Register context_value = locs()->in(0).reg();
-  Register result = locs()->out().reg();
+  Register result = locs()->out(0).reg();
 
   __ PushObject(Object::ZoneHandle(), PP);  // Make room for the result.
   __ pushq(context_value);
   compiler->GenerateRuntimeCall(token_pos(),
                                 deopt_id(),
                                 kCloneContextRuntimeEntry,
                                 1,
                                 locs());
   __ popq(result);  // Remove argument.
   __ popq(result);  // Get result (cloned context).
@@ skipping 122 matching lines @@
     __ j(GREATER, overflow);
   }
 }
 
 
 static void EmitSmiShiftLeft(FlowGraphCompiler* compiler,
                              BinarySmiOpInstr* shift_left) {
   const bool is_truncating = shift_left->is_truncating();
   const LocationSummary& locs = *shift_left->locs();
   Register left = locs.in(0).reg();
-  Register result = locs.out().reg();
+  Register result = locs.out(0).reg();
   ASSERT(left == result);
   Label* deopt = shift_left->CanDeoptimize() ?
       compiler->AddDeoptStub(shift_left->deopt_id(), kDeoptBinarySmiOp) : NULL;
   if (locs.in(1).IsConstant()) {
     const Object& constant = locs.in(1).constant();
     ASSERT(constant.IsSmi());
     // shlq operation masks the count to 6 bits.
     const intptr_t kCountLimit = 0x3F;
     const intptr_t value = Smi::Cast(constant).Value();
     if (value == 0) {
@@ skipping 125 matching lines @@
       (op_kind() != Token::kTRUNCDIV) &&
       (op_kind() != Token::kSHL) &&
       (op_kind() != Token::kMUL) &&
       (op_kind() != Token::kMOD) &&
       CanBeImmediate(right_constant->value())) {
     const intptr_t kNumTemps = 0;
     LocationSummary* summary =
         new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
     summary->set_in(0, Location::RequiresRegister());
     summary->set_in(1, Location::Constant(right_constant->value()));
-    summary->set_out(Location::SameAsFirstInput());
+    summary->set_out(0, Location::SameAsFirstInput());
     return summary;
   }
 
   if (op_kind() == Token::kTRUNCDIV) {
     const intptr_t kNumTemps = 1;
     LocationSummary* summary =
         new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
     if (RightIsPowerOfTwoConstant()) {
       summary->set_in(0, Location::RequiresRegister());
       ConstantInstr* right_constant = right()->definition()->AsConstant();
       summary->set_in(1, Location::Constant(right_constant->value()));
       summary->set_temp(0, Location::RequiresRegister());
-      summary->set_out(Location::SameAsFirstInput());
+      summary->set_out(0, Location::SameAsFirstInput());
     } else {
       // Both inputs must be writable because they will be untagged.
       summary->set_in(0, Location::RegisterLocation(RAX));
       summary->set_in(1, Location::WritableRegister());
-      summary->set_out(Location::SameAsFirstInput());
+      summary->set_out(0, Location::SameAsFirstInput());
       // Will be used for sign extension and division.
       summary->set_temp(0, Location::RegisterLocation(RDX));
     }
     return summary;
   } else if (op_kind() == Token::kMOD) {
     const intptr_t kNumTemps = 1;
     LocationSummary* summary =
         new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
     // Both inputs must be writable because they will be untagged.
     summary->set_in(0, Location::RegisterLocation(RDX));
     summary->set_in(1, Location::WritableRegister());
-    summary->set_out(Location::SameAsFirstInput());
+    summary->set_out(0, Location::SameAsFirstInput());
     // Will be used for sign extension and division.
     summary->set_temp(0, Location::RegisterLocation(RAX));
     return summary;
   } else if (op_kind() == Token::kSHR) {
     const intptr_t kNumTemps = 0;
     LocationSummary* summary =
         new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
     summary->set_in(0, Location::RequiresRegister());
     summary->set_in(1, Location::FixedRegisterOrSmiConstant(right(), RCX));
-    summary->set_out(Location::SameAsFirstInput());
+    summary->set_out(0, Location::SameAsFirstInput());
     return summary;
   } else if (op_kind() == Token::kSHL) {
     const intptr_t kNumTemps = 0;
     LocationSummary* summary =
         new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
     summary->set_in(0, Location::RequiresRegister());
     summary->set_in(1, Location::FixedRegisterOrSmiConstant(right(), RCX));
     if (!is_truncating()) {
       summary->AddTemp(Location::RequiresRegister());
     }
-    summary->set_out(Location::SameAsFirstInput());
+    summary->set_out(0, Location::SameAsFirstInput());
     return summary;
   } else {
     const intptr_t kNumTemps = 0;
     LocationSummary* summary =
         new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
     summary->set_in(0, Location::RequiresRegister());
     ConstantInstr* constant = right()->definition()->AsConstant();
     if (constant != NULL) {
       summary->set_in(1, Location::RegisterOrSmiConstant(right()));
     } else {
       summary->set_in(1, Location::PrefersRegister());
     }
-    summary->set_out(Location::SameAsFirstInput());
+    summary->set_out(0, Location::SameAsFirstInput());
     return summary;
   }
 }
 
 void BinarySmiOpInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   if (op_kind() == Token::kSHL) {
     EmitSmiShiftLeft(compiler, this);
     return;
   }
 
   ASSERT(!is_truncating());
   Register left = locs()->in(0).reg();
-  Register result = locs()->out().reg();
+  Register result = locs()->out(0).reg();
   ASSERT(left == result);
   Label* deopt = NULL;
   if (CanDeoptimize()) {
     deopt = compiler->AddDeoptStub(deopt_id(),
                                    kDeoptBinarySmiOp);
   }
 
   if (locs()->in(1).IsConstant()) {
     const Object& constant = locs()->in(1).constant();
     ASSERT(constant.IsSmi());
@@ skipping 382 matching lines @@
 
 
 LocationSummary* BoxDoubleInstr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 1;
   const intptr_t kNumTemps = 0;
   LocationSummary* summary =
       new LocationSummary(kNumInputs,
                           kNumTemps,
                           LocationSummary::kCallOnSlowPath);
   summary->set_in(0, Location::RequiresFpuRegister());
-  summary->set_out(Location::RequiresRegister());
+  summary->set_out(0, Location::RequiresRegister());
   return summary;
 }
 
 
 void BoxDoubleInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   BoxDoubleSlowPath* slow_path = new BoxDoubleSlowPath(this);
   compiler->AddSlowPathCode(slow_path);
 
-  Register out_reg = locs()->out().reg();
+  Register out_reg = locs()->out(0).reg();
   XmmRegister value = locs()->in(0).fpu_reg();
 
   __ TryAllocate(compiler->double_class(),
                  slow_path->entry_label(),
                  Assembler::kFarJump,
                  out_reg,
                  PP);
   __ Bind(slow_path->exit_label());
   __ movsd(FieldAddress(out_reg, Double::value_offset()), value);
 }
 
 
 LocationSummary* UnboxDoubleInstr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 1;
   const intptr_t kNumTemps = 0;
   LocationSummary* summary =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
   const bool needs_writable_input = (value()->Type()->ToCid() != kDoubleCid);
   summary->set_in(0, needs_writable_input
                      ? Location::WritableRegister()
                      : Location::RequiresRegister());
-  summary->set_out(Location::RequiresFpuRegister());
+  summary->set_out(0, Location::RequiresFpuRegister());
   return summary;
 }
 
 
 void UnboxDoubleInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   const intptr_t value_cid = value()->Type()->ToCid();
   const Register value = locs()->in(0).reg();
-  const XmmRegister result = locs()->out().fpu_reg();
+  const XmmRegister result = locs()->out(0).fpu_reg();
 
   if (value_cid == kDoubleCid) {
     __ movsd(result, FieldAddress(value, Double::value_offset()));
   } else if (value_cid == kSmiCid) {
     __ SmiUntag(value);  // Untag input before conversion.
     __ cvtsi2sd(result, value);
   } else {
     Label* deopt = compiler->AddDeoptStub(deopt_id_, kDeoptBinaryDoubleOp);
     Label is_smi, done;
     __ testq(value, Immediate(kSmiTagMask));
@@ skipping 11 matching lines @@
 
 
 LocationSummary* BoxFloat32x4Instr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 1;
   const intptr_t kNumTemps = 0;
   LocationSummary* summary =
       new LocationSummary(kNumInputs,
                           kNumTemps,
                           LocationSummary::kCallOnSlowPath);
   summary->set_in(0, Location::RequiresFpuRegister());
-  summary->set_out(Location::RequiresRegister());
+  summary->set_out(0, Location::RequiresRegister());
   return summary;
 }
 
 
 void BoxFloat32x4Instr::EmitNativeCode(FlowGraphCompiler* compiler) {
   BoxFloat32x4SlowPath* slow_path = new BoxFloat32x4SlowPath(this);
   compiler->AddSlowPathCode(slow_path);
 
-  Register out_reg = locs()->out().reg();
+  Register out_reg = locs()->out(0).reg();
   XmmRegister value = locs()->in(0).fpu_reg();
 
   __ TryAllocate(compiler->float32x4_class(),
                  slow_path->entry_label(),
                  Assembler::kFarJump,
                  out_reg,
                  PP);
   __ Bind(slow_path->exit_label());
   __ movups(FieldAddress(out_reg, Float32x4::value_offset()), value);
 }
 
 
 LocationSummary* UnboxFloat32x4Instr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 1;
   return LocationSummary::Make(kNumInputs,
                                Location::RequiresFpuRegister(),
                                LocationSummary::kNoCall);
 }
 
 
 void UnboxFloat32x4Instr::EmitNativeCode(FlowGraphCompiler* compiler) {
   const intptr_t value_cid = value()->Type()->ToCid();
   const Register value = locs()->in(0).reg();
-  const XmmRegister result = locs()->out().fpu_reg();
+  const XmmRegister result = locs()->out(0).fpu_reg();
 
   if (value_cid != kFloat32x4Cid) {
     Label* deopt = compiler->AddDeoptStub(deopt_id_, kDeoptCheckClass);
     __ testq(value, Immediate(kSmiTagMask));
     __ j(ZERO, deopt);
     __ CompareClassId(value, kFloat32x4Cid);
     __ j(NOT_EQUAL, deopt);
   }
   __ movups(result, FieldAddress(value, Float32x4::value_offset()));
 }
 
 
 LocationSummary* BoxFloat64x2Instr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 1;
   const intptr_t kNumTemps = 0;
   LocationSummary* summary =
       new LocationSummary(kNumInputs,
                           kNumTemps,
                           LocationSummary::kCallOnSlowPath);
   summary->set_in(0, Location::RequiresFpuRegister());
-  summary->set_out(Location::RequiresRegister());
+  summary->set_out(0, Location::RequiresRegister());
   return summary;
 }
 
 
 void BoxFloat64x2Instr::EmitNativeCode(FlowGraphCompiler* compiler) {
   BoxFloat64x2SlowPath* slow_path = new BoxFloat64x2SlowPath(this);
   compiler->AddSlowPathCode(slow_path);
 
-  Register out_reg = locs()->out().reg();
+  Register out_reg = locs()->out(0).reg();
   XmmRegister value = locs()->in(0).fpu_reg();
 
   __ TryAllocate(compiler->float64x2_class(),
                  slow_path->entry_label(),
                  Assembler::kFarJump,
                  out_reg,
                  kNoRegister);
   __ Bind(slow_path->exit_label());
   __ movups(FieldAddress(out_reg, Float64x2::value_offset()), value);
 }
 
 
 LocationSummary* UnboxFloat64x2Instr::MakeLocationSummary(bool opt) const {
   const intptr_t value_cid = value()->Type()->ToCid();
   const intptr_t kNumInputs = 1;
   const intptr_t kNumTemps = value_cid == kFloat64x2Cid ? 0 : 1;
   LocationSummary* summary =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
   summary->set_in(0, Location::RequiresRegister());
-  summary->set_out(Location::RequiresFpuRegister());
+  summary->set_out(0, Location::RequiresFpuRegister());
   return summary;
 }
 
 
 void UnboxFloat64x2Instr::EmitNativeCode(FlowGraphCompiler* compiler) {
   const intptr_t value_cid = value()->Type()->ToCid();
   const Register value = locs()->in(0).reg();
-  const XmmRegister result = locs()->out().fpu_reg();
+  const XmmRegister result = locs()->out(0).fpu_reg();
 
   if (value_cid != kFloat64x2Cid) {
     Label* deopt = compiler->AddDeoptStub(deopt_id_, kDeoptCheckClass);
     __ testq(value, Immediate(kSmiTagMask));
     __ j(ZERO, deopt);
     __ CompareClassId(value, kFloat64x2Cid);
     __ j(NOT_EQUAL, deopt);
   }
   __ movups(result, FieldAddress(value, Float64x2::value_offset()));
 }
 
 
 LocationSummary* BoxInt32x4Instr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 1;
   const intptr_t kNumTemps = 0;
   LocationSummary* summary =
       new LocationSummary(kNumInputs,
                           kNumTemps,
                           LocationSummary::kCallOnSlowPath);
   summary->set_in(0, Location::RequiresFpuRegister());
-  summary->set_out(Location::RequiresRegister());
+  summary->set_out(0, Location::RequiresRegister());
   return summary;
 }
 
 
 class BoxInt32x4SlowPath : public SlowPathCode {
  public:
   explicit BoxInt32x4SlowPath(BoxInt32x4Instr* instruction)
       : instruction_(instruction) { }
 
   virtual void EmitNativeCode(FlowGraphCompiler* compiler) {
     __ Comment("BoxInt32x4SlowPath");
     __ Bind(entry_label());
     const Class& int32x4_class = compiler->int32x4_class();
     const Code& stub =
         Code::Handle(StubCode::GetAllocationStubForClass(int32x4_class));
     const ExternalLabel label(int32x4_class.ToCString(), stub.EntryPoint());
 
     LocationSummary* locs = instruction_->locs();
-    locs->live_registers()->Remove(locs->out());
+    locs->live_registers()->Remove(locs->out(0));
 
     compiler->SaveLiveRegisters(locs);
     compiler->GenerateCall(Scanner::kNoSourcePos,  // No token position.
                            &label,
                            PcDescriptors::kOther,
                            locs);
-    __ MoveRegister(locs->out().reg(), RAX);
+    __ MoveRegister(locs->out(0).reg(), RAX);
     compiler->RestoreLiveRegisters(locs);
 
     __ jmp(exit_label());
   }
 
  private:
   BoxInt32x4Instr* instruction_;
 };
 
 
 void BoxInt32x4Instr::EmitNativeCode(FlowGraphCompiler* compiler) {
   BoxInt32x4SlowPath* slow_path = new BoxInt32x4SlowPath(this);
   compiler->AddSlowPathCode(slow_path);
 
-  Register out_reg = locs()->out().reg();
+  Register out_reg = locs()->out(0).reg();
   XmmRegister value = locs()->in(0).fpu_reg();
 
   __ TryAllocate(compiler->int32x4_class(),
                  slow_path->entry_label(),
                  Assembler::kFarJump,
                  out_reg,
                  PP);
   __ Bind(slow_path->exit_label());
   __ movups(FieldAddress(out_reg, Int32x4::value_offset()), value);
 }
 
 
 LocationSummary* UnboxInt32x4Instr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 1;
   const intptr_t kNumTemps = 0;
   LocationSummary* summary =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
   summary->set_in(0, Location::RequiresRegister());
-  summary->set_out(Location::RequiresFpuRegister());
+  summary->set_out(0, Location::RequiresFpuRegister());
   return summary;
 }
 
 
 void UnboxInt32x4Instr::EmitNativeCode(FlowGraphCompiler* compiler) {
   const intptr_t value_cid = value()->Type()->ToCid();
   const Register value = locs()->in(0).reg();
-  const XmmRegister result = locs()->out().fpu_reg();
+  const XmmRegister result = locs()->out(0).fpu_reg();
 
   if (value_cid != kInt32x4Cid) {
     Label* deopt = compiler->AddDeoptStub(deopt_id_, kDeoptCheckClass);
     __ testq(value, Immediate(kSmiTagMask));
     __ j(ZERO, deopt);
     __ CompareClassId(value, kInt32x4Cid);
     __ j(NOT_EQUAL, deopt);
   }
   __ movups(result, FieldAddress(value, Int32x4::value_offset()));
 }
 
 
 LocationSummary* BinaryDoubleOpInstr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 2;
   const intptr_t kNumTemps = 0;
   LocationSummary* summary =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
   summary->set_in(0, Location::RequiresFpuRegister());
   summary->set_in(1, Location::RequiresFpuRegister());
-  summary->set_out(Location::SameAsFirstInput());
+  summary->set_out(0, Location::SameAsFirstInput());
   return summary;
 }
 
 
 void BinaryDoubleOpInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   XmmRegister left = locs()->in(0).fpu_reg();
   XmmRegister right = locs()->in(1).fpu_reg();
 
-  ASSERT(locs()->out().fpu_reg() == left);
+  ASSERT(locs()->out(0).fpu_reg() == left);
 
   switch (op_kind()) {
     case Token::kADD: __ addsd(left, right); break;
     case Token::kSUB: __ subsd(left, right); break;
     case Token::kMUL: __ mulsd(left, right); break;
     case Token::kDIV: __ divsd(left, right); break;
     default: UNREACHABLE();
   }
 }
 
 
 LocationSummary* BinaryFloat32x4OpInstr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 2;
   const intptr_t kNumTemps = 0;
   LocationSummary* summary =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
   summary->set_in(0, Location::RequiresFpuRegister());
   summary->set_in(1, Location::RequiresFpuRegister());
-  summary->set_out(Location::SameAsFirstInput());
+  summary->set_out(0, Location::SameAsFirstInput());
   return summary;
 }
 
 
 void BinaryFloat32x4OpInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   XmmRegister left = locs()->in(0).fpu_reg();
   XmmRegister right = locs()->in(1).fpu_reg();
 
-  ASSERT(locs()->out().fpu_reg() == left);
+  ASSERT(locs()->out(0).fpu_reg() == left);
 
   switch (op_kind()) {
     case Token::kADD: __ addps(left, right); break;
     case Token::kSUB: __ subps(left, right); break;
     case Token::kMUL: __ mulps(left, right); break;
     case Token::kDIV: __ divps(left, right); break;
     default: UNREACHABLE();
   }
 }
 
 
 LocationSummary* BinaryFloat64x2OpInstr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 2;
   const intptr_t kNumTemps = 0;
   LocationSummary* summary =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
   summary->set_in(0, Location::RequiresFpuRegister());
   summary->set_in(1, Location::RequiresFpuRegister());
-  summary->set_out(Location::SameAsFirstInput());
+  summary->set_out(0, Location::SameAsFirstInput());
   return summary;
 }
 
 
 void BinaryFloat64x2OpInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   XmmRegister left = locs()->in(0).fpu_reg();
   XmmRegister right = locs()->in(1).fpu_reg();
 
-  ASSERT(locs()->out().fpu_reg() == left);
+  ASSERT(locs()->out(0).fpu_reg() == left);
 
   switch (op_kind()) {
     case Token::kADD: __ addpd(left, right); break;
     case Token::kSUB: __ subpd(left, right); break;
     case Token::kMUL: __ mulpd(left, right); break;
     case Token::kDIV: __ divpd(left, right); break;
     default: UNREACHABLE();
   }
 }
 
 
 LocationSummary* Simd32x4ShuffleInstr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 1;
   const intptr_t kNumTemps = 0;
   LocationSummary* summary =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
   summary->set_in(0, Location::RequiresFpuRegister());
-  summary->set_out(Location::SameAsFirstInput());
+  summary->set_out(0, Location::SameAsFirstInput());
   return summary;
 }
 
 
 void Simd32x4ShuffleInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   XmmRegister value = locs()->in(0).fpu_reg();
 
-  ASSERT(locs()->out().fpu_reg() == value);
+  ASSERT(locs()->out(0).fpu_reg() == value);
 
   switch (op_kind()) {
     case MethodRecognizer::kFloat32x4ShuffleX:
       // Shuffle not necessary.
       __ cvtss2sd(value, value);
       break;
     case MethodRecognizer::kFloat32x4ShuffleY:
       __ shufps(value, value, Immediate(0x55));
       __ cvtss2sd(value, value);
       break;
@@ skipping 14 matching lines @@
 }
 
 
 LocationSummary* Simd32x4ShuffleMixInstr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 2;
   const intptr_t kNumTemps = 0;
   LocationSummary* summary =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
   summary->set_in(0, Location::RequiresFpuRegister());
   summary->set_in(1, Location::RequiresFpuRegister());
-  summary->set_out(Location::SameAsFirstInput());
+  summary->set_out(0, Location::SameAsFirstInput());
   return summary;
 }
 
 
 void Simd32x4ShuffleMixInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   XmmRegister left = locs()->in(0).fpu_reg();
   XmmRegister right = locs()->in(1).fpu_reg();
 
-  ASSERT(locs()->out().fpu_reg() == left);
+  ASSERT(locs()->out(0).fpu_reg() == left);
   switch (op_kind()) {
     case MethodRecognizer::kFloat32x4ShuffleMix:
     case MethodRecognizer::kInt32x4ShuffleMix:
       __ shufps(left, right, Immediate(mask_));
       break;
     default: UNREACHABLE();
   }
 }
 
 
 LocationSummary* Simd32x4GetSignMaskInstr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 1;
   const intptr_t kNumTemps = 0;
   LocationSummary* summary =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
   summary->set_in(0, Location::RequiresFpuRegister());
-  summary->set_out(Location::RequiresRegister());
+  summary->set_out(0, Location::RequiresRegister());
   return summary;
 }
 
 
 void Simd32x4GetSignMaskInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   XmmRegister value = locs()->in(0).fpu_reg();
-  Register out = locs()->out().reg();
+  Register out = locs()->out(0).reg();
 
   __ movmskps(out, value);
   __ SmiTag(out);
 }
 
 
 LocationSummary* Float32x4ConstructorInstr::MakeLocationSummary(
     bool opt) const {
   const intptr_t kNumInputs = 4;
   const intptr_t kNumTemps = 0;
   LocationSummary* summary =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
   summary->set_in(0, Location::RequiresFpuRegister());
   summary->set_in(1, Location::RequiresFpuRegister());
   summary->set_in(2, Location::RequiresFpuRegister());
   summary->set_in(3, Location::RequiresFpuRegister());
-  summary->set_out(Location::SameAsFirstInput());
+  summary->set_out(0, Location::SameAsFirstInput());
   return summary;
 }
 
 
 void Float32x4ConstructorInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   XmmRegister v0 = locs()->in(0).fpu_reg();
   XmmRegister v1 = locs()->in(1).fpu_reg();
   XmmRegister v2 = locs()->in(2).fpu_reg();
   XmmRegister v3 = locs()->in(3).fpu_reg();
-  ASSERT(v0 == locs()->out().fpu_reg());
+  ASSERT(v0 == locs()->out(0).fpu_reg());
   __ AddImmediate(RSP, Immediate(-16), PP);
   __ cvtsd2ss(v0, v0);
   __ movss(Address(RSP, 0), v0);
   __ movsd(v0, v1);
   __ cvtsd2ss(v0, v0);
   __ movss(Address(RSP, 4), v0);
   __ movsd(v0, v2);
   __ cvtsd2ss(v0, v0);
   __ movss(Address(RSP, 8), v0);
   __ movsd(v0, v3);
   __ cvtsd2ss(v0, v0);
   __ movss(Address(RSP, 12), v0);
   __ movups(v0, Address(RSP, 0));
   __ AddImmediate(RSP, Immediate(16), PP);
 }
 
 
 LocationSummary* Float32x4ZeroInstr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 0;
   const intptr_t kNumTemps = 0;
   LocationSummary* summary =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
-  summary->set_out(Location::RequiresFpuRegister());
+  summary->set_out(0, Location::RequiresFpuRegister());
   return summary;
 }
 
 
 void Float32x4ZeroInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
-  XmmRegister value = locs()->out().fpu_reg();
+  XmmRegister value = locs()->out(0).fpu_reg();
   __ xorps(value, value);
 }
 
 
 LocationSummary* Float32x4SplatInstr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 1;
   const intptr_t kNumTemps = 0;
   LocationSummary* summary =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
   summary->set_in(0, Location::RequiresFpuRegister());
-  summary->set_out(Location::SameAsFirstInput());
+  summary->set_out(0, Location::SameAsFirstInput());
   return summary;
 }
 
 
 void Float32x4SplatInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
-  XmmRegister value = locs()->out().fpu_reg();
-  ASSERT(locs()->in(0).fpu_reg() == locs()->out().fpu_reg());
+  XmmRegister value = locs()->out(0).fpu_reg();
+  ASSERT(locs()->in(0).fpu_reg() == locs()->out(0).fpu_reg());
   // Convert to Float32.
   __ cvtsd2ss(value, value);
   // Splat across all lanes.
   __ shufps(value, value, Immediate(0x00));
 }
 
 
 LocationSummary* Float32x4ComparisonInstr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 2;
   const intptr_t kNumTemps = 0;
   LocationSummary* summary =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
   summary->set_in(0, Location::RequiresFpuRegister());
   summary->set_in(1, Location::RequiresFpuRegister());
-  summary->set_out(Location::SameAsFirstInput());
+  summary->set_out(0, Location::SameAsFirstInput());
   return summary;
 }
 
 
 void Float32x4ComparisonInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   XmmRegister left = locs()->in(0).fpu_reg();
   XmmRegister right = locs()->in(1).fpu_reg();
 
-  ASSERT(locs()->out().fpu_reg() == left);
+  ASSERT(locs()->out(0).fpu_reg() == left);
 
   switch (op_kind()) {
     case MethodRecognizer::kFloat32x4Equal:
       __ cmppseq(left, right);
       break;
     case MethodRecognizer::kFloat32x4NotEqual:
       __ cmppsneq(left, right);
       break;
     case MethodRecognizer::kFloat32x4GreaterThan:
       __ cmppsnle(left, right);
@@ skipping 13 matching lines @@
 }
 
 
 LocationSummary* Float32x4MinMaxInstr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 2;
   const intptr_t kNumTemps = 0;
   LocationSummary* summary =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
   summary->set_in(0, Location::RequiresFpuRegister());
   summary->set_in(1, Location::RequiresFpuRegister());
-  summary->set_out(Location::SameAsFirstInput());
+  summary->set_out(0, Location::SameAsFirstInput());
   return summary;
 }
 
 
 void Float32x4MinMaxInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   XmmRegister left = locs()->in(0).fpu_reg();
   XmmRegister right = locs()->in(1).fpu_reg();
 
-  ASSERT(locs()->out().fpu_reg() == left);
+  ASSERT(locs()->out(0).fpu_reg() == left);
 
   switch (op_kind()) {
     case MethodRecognizer::kFloat32x4Min:
       __ minps(left, right);
       break;
     case MethodRecognizer::kFloat32x4Max:
       __ maxps(left, right);
       break;
     default: UNREACHABLE();
   }
 }
 
 
 LocationSummary* Float32x4ScaleInstr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 2;
   const intptr_t kNumTemps = 0;
   LocationSummary* summary =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
   summary->set_in(0, Location::RequiresFpuRegister());
   summary->set_in(1, Location::RequiresFpuRegister());
-  summary->set_out(Location::SameAsFirstInput());
+  summary->set_out(0, Location::SameAsFirstInput());
   return summary;
 }
 
 
 void Float32x4ScaleInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   XmmRegister left = locs()->in(0).fpu_reg();
   XmmRegister right = locs()->in(1).fpu_reg();
 
-  ASSERT(locs()->out().fpu_reg() == left);
+  ASSERT(locs()->out(0).fpu_reg() == left);
 
   switch (op_kind()) {
     case MethodRecognizer::kFloat32x4Scale:
       __ cvtsd2ss(left, left);
       __ shufps(left, left, Immediate(0x00));
       __ mulps(left, right);
       break;
     default: UNREACHABLE();
   }
 }
 
 
 LocationSummary* Float32x4SqrtInstr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 1;
   const intptr_t kNumTemps = 0;
   LocationSummary* summary =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
   summary->set_in(0, Location::RequiresFpuRegister());
-  summary->set_out(Location::SameAsFirstInput());
+  summary->set_out(0, Location::SameAsFirstInput());
   return summary;
 }
 
 
 void Float32x4SqrtInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   XmmRegister left = locs()->in(0).fpu_reg();
 
-  ASSERT(locs()->out().fpu_reg() == left);
+  ASSERT(locs()->out(0).fpu_reg() == left);
 
   switch (op_kind()) {
     case MethodRecognizer::kFloat32x4Sqrt:
       __ sqrtps(left);
       break;
     case MethodRecognizer::kFloat32x4Reciprocal:
       __ reciprocalps(left);
       break;
     case MethodRecognizer::kFloat32x4ReciprocalSqrt:
       __ rsqrtps(left);
       break;
     default: UNREACHABLE();
   }
 }
 
 
 LocationSummary* Float32x4ZeroArgInstr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 1;
   const intptr_t kNumTemps = 0;
   LocationSummary* summary =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
   summary->set_in(0, Location::RequiresFpuRegister());
-  summary->set_out(Location::SameAsFirstInput());
+  summary->set_out(0, Location::SameAsFirstInput());
   return summary;
 }
 
 
 void Float32x4ZeroArgInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   XmmRegister left = locs()->in(0).fpu_reg();
 
-  ASSERT(locs()->out().fpu_reg() == left);
+  ASSERT(locs()->out(0).fpu_reg() == left);
   switch (op_kind()) {
     case MethodRecognizer::kFloat32x4Negate:
       __ negateps(left);
       break;
     case MethodRecognizer::kFloat32x4Absolute:
       __ absps(left);
       break;
     default: UNREACHABLE();
   }
 }
 
 
 LocationSummary* Float32x4ClampInstr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 3;
   const intptr_t kNumTemps = 0;
   LocationSummary* summary =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
   summary->set_in(0, Location::RequiresFpuRegister());
   summary->set_in(1, Location::RequiresFpuRegister());
   summary->set_in(2, Location::RequiresFpuRegister());
-  summary->set_out(Location::SameAsFirstInput());
+  summary->set_out(0, Location::SameAsFirstInput());
   return summary;
 }
 
 
 void Float32x4ClampInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   XmmRegister left = locs()->in(0).fpu_reg();
   XmmRegister lower = locs()->in(1).fpu_reg();
   XmmRegister upper = locs()->in(2).fpu_reg();
-  ASSERT(locs()->out().fpu_reg() == left);
+  ASSERT(locs()->out(0).fpu_reg() == left);
   __ minps(left, upper);
   __ maxps(left, lower);
 }
 
 
 LocationSummary* Float32x4WithInstr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 2;
   const intptr_t kNumTemps = 0;
   LocationSummary* summary =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
   summary->set_in(0, Location::RequiresFpuRegister());
   summary->set_in(1, Location::RequiresFpuRegister());
-  summary->set_out(Location::SameAsFirstInput());
+  summary->set_out(0, Location::SameAsFirstInput());
   return summary;
 }
 
 
 void Float32x4WithInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   XmmRegister replacement = locs()->in(0).fpu_reg();
   XmmRegister value = locs()->in(1).fpu_reg();
 
-  ASSERT(locs()->out().fpu_reg() == replacement);
+  ASSERT(locs()->out(0).fpu_reg() == replacement);
 
   switch (op_kind()) {
     case MethodRecognizer::kFloat32x4WithX:
       __ cvtsd2ss(replacement, replacement);
       __ AddImmediate(RSP, Immediate(-16), PP);
       // Move value to stack.
       __ movups(Address(RSP, 0), value);
       // Write over X value.
       __ movss(Address(RSP, 0), replacement);
       // Move updated value into output register.
@@ skipping 37 matching lines @@
   }
 }
 
 
 LocationSummary* Float32x4ToInt32x4Instr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 1;
   const intptr_t kNumTemps = 0;
   LocationSummary* summary =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
   summary->set_in(0, Location::RequiresFpuRegister());
-  summary->set_out(Location::SameAsFirstInput());
+  summary->set_out(0, Location::SameAsFirstInput());
   return summary;
 }
 
 
 void Float32x4ToInt32x4Instr::EmitNativeCode(FlowGraphCompiler* compiler) {
   // NOP.
 }
 
 
 LocationSummary* Simd64x2ShuffleInstr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 1;
   const intptr_t kNumTemps = 0;
   LocationSummary* summary =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
   summary->set_in(0, Location::RequiresFpuRegister());
-  summary->set_out(Location::SameAsFirstInput());
+  summary->set_out(0, Location::SameAsFirstInput());
   return summary;
 }
 
 
 void Simd64x2ShuffleInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   XmmRegister value = locs()->in(0).fpu_reg();
 
-  ASSERT(locs()->out().fpu_reg() == value);
+  ASSERT(locs()->out(0).fpu_reg() == value);
   switch (op_kind()) {
     case MethodRecognizer::kFloat64x2GetX:
       // nop.
       break;
     case MethodRecognizer::kFloat64x2GetY:
       __ shufpd(value, value, Immediate(0x33));
       break;
     default: UNREACHABLE();
   }
 }
 
 
 LocationSummary* Float64x2ZeroInstr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 0;
   const intptr_t kNumTemps = 0;
   LocationSummary* summary =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
-  summary->set_out(Location::RequiresFpuRegister());
+  summary->set_out(0, Location::RequiresFpuRegister());
   return summary;
 }
 
 
 void Float64x2ZeroInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
-  XmmRegister value = locs()->out().fpu_reg();
+  XmmRegister value = locs()->out(0).fpu_reg();
   __ xorpd(value, value);
 }
 
 
 LocationSummary* Float64x2SplatInstr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 1;
   const intptr_t kNumTemps = 0;
   LocationSummary* summary =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
   summary->set_in(0, Location::RequiresFpuRegister());
-  summary->set_out(Location::SameAsFirstInput());
+  summary->set_out(0, Location::SameAsFirstInput());
   return summary;
 }
 
 
 void Float64x2SplatInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
-  XmmRegister value = locs()->out().fpu_reg();
+  XmmRegister value = locs()->out(0).fpu_reg();
   __ shufpd(value, value, Immediate(0x0));
 }
 
 
 LocationSummary* Float64x2ConstructorInstr::MakeLocationSummary(
     bool opt) const {
   const intptr_t kNumInputs = 2;
   const intptr_t kNumTemps = 0;
   LocationSummary* summary =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
   summary->set_in(0, Location::RequiresFpuRegister());
   summary->set_in(1, Location::RequiresFpuRegister());
-  summary->set_out(Location::SameAsFirstInput());
+  summary->set_out(0, Location::SameAsFirstInput());
   return summary;
 }
 
 
 void Float64x2ConstructorInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   XmmRegister v0 = locs()->in(0).fpu_reg();
   XmmRegister v1 = locs()->in(1).fpu_reg();
-  ASSERT(v0 == locs()->out().fpu_reg());
+  ASSERT(v0 == locs()->out(0).fpu_reg());
   __ AddImmediate(RSP, Immediate(-16), PP);
   __ movsd(Address(RSP, 0), v0);
   __ movsd(Address(RSP, 8), v1);
   __ movups(v0, Address(RSP, 0));
   __ AddImmediate(RSP, Immediate(16), PP);
 }
 
 
 LocationSummary* Float64x2ToFloat32x4Instr::MakeLocationSummary(
     bool opt) const {
   const intptr_t kNumInputs = 1;
   const intptr_t kNumTemps = 0;
   LocationSummary* summary =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
   summary->set_in(0, Location::RequiresFpuRegister());
-  summary->set_out(Location::SameAsFirstInput());
+  summary->set_out(0, Location::SameAsFirstInput());
   return summary;
 }
 
 
 void Float64x2ToFloat32x4Instr::EmitNativeCode(FlowGraphCompiler* compiler) {
-  XmmRegister value = locs()->out().fpu_reg();
+  XmmRegister value = locs()->out(0).fpu_reg();
   __ cvtpd2ps(value, value);
 }
 
 
 LocationSummary* Float32x4ToFloat64x2Instr::MakeLocationSummary(
     bool opt) const {
   const intptr_t kNumInputs = 1;
   const intptr_t kNumTemps = 0;
   LocationSummary* summary =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
   summary->set_in(0, Location::RequiresFpuRegister());
-  summary->set_out(Location::SameAsFirstInput());
+  summary->set_out(0, Location::SameAsFirstInput());
   return summary;
 }
 
 
 void Float32x4ToFloat64x2Instr::EmitNativeCode(FlowGraphCompiler* compiler) {
-  XmmRegister value = locs()->out().fpu_reg();
+  XmmRegister value = locs()->out(0).fpu_reg();
   __ cvtps2pd(value, value);
 }
 
 
 LocationSummary* Float64x2ZeroArgInstr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 1;
   const intptr_t kNumTemps = 0;
   LocationSummary* summary =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
   summary->set_in(0, Location::RequiresFpuRegister());
   if (representation() == kTagged) {
     ASSERT(op_kind() == MethodRecognizer::kFloat64x2GetSignMask);
-    summary->set_out(Location::RequiresRegister());
+    summary->set_out(0, Location::RequiresRegister());
   } else {
     ASSERT(representation() == kUnboxedFloat64x2);
-    summary->set_out(Location::SameAsFirstInput());
+    summary->set_out(0, Location::SameAsFirstInput());
   }
   return summary;
 }
 
 
 void Float64x2ZeroArgInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   XmmRegister left = locs()->in(0).fpu_reg();
 
   ASSERT((op_kind() == MethodRecognizer::kFloat64x2GetSignMask) ||
-         (locs()->out().fpu_reg() == left));
+         (locs()->out(0).fpu_reg() == left));
 
   switch (op_kind()) {
     case MethodRecognizer::kFloat64x2Negate:
       __ negatepd(left);
       break;
     case MethodRecognizer::kFloat64x2Abs:
       __ abspd(left);
       break;
     case MethodRecognizer::kFloat64x2Sqrt:
       __ sqrtpd(left);
       break;
     case MethodRecognizer::kFloat64x2GetSignMask:
-      __ movmskpd(locs()->out().reg(), left);
-      __ SmiTag(locs()->out().reg());
+      __ movmskpd(locs()->out(0).reg(), left);
+      __ SmiTag(locs()->out(0).reg());
       break;
     default: UNREACHABLE();
   }
 }
 
 
 LocationSummary* Float64x2OneArgInstr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 2;
   const intptr_t kNumTemps = 0;
   LocationSummary* summary =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
   summary->set_in(0, Location::RequiresFpuRegister());
   summary->set_in(1, Location::RequiresFpuRegister());
-  summary->set_out(Location::SameAsFirstInput());
+  summary->set_out(0, Location::SameAsFirstInput());
   return summary;
 }
 
 
 void Float64x2OneArgInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   XmmRegister left = locs()->in(0).fpu_reg();
   XmmRegister right = locs()->in(1).fpu_reg();
-  ASSERT((locs()->out().fpu_reg() == left));
+  ASSERT((locs()->out(0).fpu_reg() == left));
 
   switch (op_kind()) {
     case MethodRecognizer::kFloat64x2Scale:
       __ shufpd(right, right, Immediate(0x00));
       __ mulpd(left, right);
       break;
     case MethodRecognizer::kFloat64x2WithX:
       __ subq(RSP, Immediate(16));
       // Move value to stack.
       __ movups(Address(RSP, 0), left);
@@ skipping 28 matching lines @@
     bool opt) const {
   const intptr_t kNumInputs = 4;
   const intptr_t kNumTemps = 1;
   LocationSummary* summary =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
   summary->set_in(0, Location::RequiresRegister());
   summary->set_in(1, Location::RequiresRegister());
   summary->set_in(2, Location::RequiresRegister());
   summary->set_in(3, Location::RequiresRegister());
   summary->set_temp(0, Location::RequiresRegister());
-  summary->set_out(Location::RequiresFpuRegister());
+  summary->set_out(0, Location::RequiresFpuRegister());
   return summary;
 }
 
 
 void Int32x4BoolConstructorInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   Register v0 = locs()->in(0).reg();
   Register v1 = locs()->in(1).reg();
   Register v2 = locs()->in(2).reg();
   Register v3 = locs()->in(3).reg();
   Register temp = locs()->temp(0).reg();
-  XmmRegister result = locs()->out().fpu_reg();
+  XmmRegister result = locs()->out(0).fpu_reg();
   Label x_false, x_done;
   Label y_false, y_done;
   Label z_false, z_done;
   Label w_false, w_done;
   __ AddImmediate(RSP, Immediate(-16), PP);
 
   __ CompareObject(v0, Bool::True(), PP);
   __ j(NOT_EQUAL, &x_false);
   __ LoadImmediate(temp, Immediate(0xFFFFFFFF), PP);
   __ jmp(&x_done);
@@ skipping 33 matching lines @@
   __ AddImmediate(RSP, Immediate(16), PP);
 }
 
 
 LocationSummary* Int32x4GetFlagInstr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 1;
   const intptr_t kNumTemps = 0;
   LocationSummary* summary =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
   summary->set_in(0, Location::RequiresFpuRegister());
-  summary->set_out(Location::RequiresRegister());
+  summary->set_out(0, Location::RequiresRegister());
   return summary;
 }
 
 
 void Int32x4GetFlagInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   XmmRegister value = locs()->in(0).fpu_reg();
-  Register result = locs()->out().reg();
+  Register result = locs()->out(0).reg();
   Label done;
   Label non_zero;
   __ AddImmediate(RSP, Immediate(-16), PP);
   // Move value to stack.
   __ movups(Address(RSP, 0), value);
   switch (op_kind()) {
     case MethodRecognizer::kInt32x4GetFlagX:
       __ movl(result, Address(RSP, 0));
       break;
     case MethodRecognizer::kInt32x4GetFlagY:
@@ skipping 20 matching lines @@
 
 LocationSummary* Int32x4SelectInstr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 3;
   const intptr_t kNumTemps = 1;
   LocationSummary* summary =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
   summary->set_in(0, Location::RequiresFpuRegister());
   summary->set_in(1, Location::RequiresFpuRegister());
   summary->set_in(2, Location::RequiresFpuRegister());
   summary->set_temp(0, Location::RequiresFpuRegister());
-  summary->set_out(Location::SameAsFirstInput());
+  summary->set_out(0, Location::SameAsFirstInput());
   return summary;
 }
 
 
 void Int32x4SelectInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   XmmRegister mask = locs()->in(0).fpu_reg();
   XmmRegister trueValue = locs()->in(1).fpu_reg();
   XmmRegister falseValue = locs()->in(2).fpu_reg();
-  XmmRegister out = locs()->out().fpu_reg();
+  XmmRegister out = locs()->out(0).fpu_reg();
   XmmRegister temp = locs()->temp(0).fpu_reg();
   ASSERT(out == mask);
   // Copy mask.
   __ movaps(temp, mask);
   // Invert it.
   __ notps(temp);
   // mask = mask & trueValue.
   __ andps(mask, trueValue);
   // temp = temp & falseValue.
   __ andps(temp, falseValue);
   // out = mask | temp.
   __ orps(mask, temp);
 }
 
 
 LocationSummary* Int32x4SetFlagInstr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 2;
   const intptr_t kNumTemps = 1;
   LocationSummary* summary =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
   summary->set_in(0, Location::RequiresFpuRegister());
   summary->set_in(1, Location::RequiresRegister());
   summary->set_temp(0, Location::RequiresRegister());
-  summary->set_out(Location::SameAsFirstInput());
+  summary->set_out(0, Location::SameAsFirstInput());
   return summary;
 }
 
 
 void Int32x4SetFlagInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   XmmRegister mask = locs()->in(0).fpu_reg();
   Register flag = locs()->in(1).reg();
   Register temp = locs()->temp(0).reg();
-  ASSERT(mask == locs()->out().fpu_reg());
+  ASSERT(mask == locs()->out(0).fpu_reg());
   __ AddImmediate(RSP, Immediate(-16), PP);
   // Copy mask to stack.
   __ movups(Address(RSP, 0), mask);
   Label falsePath, exitPath;
   __ CompareObject(flag, Bool::True(), PP);
   __ j(NOT_EQUAL, &falsePath);
   switch (op_kind()) {
     case MethodRecognizer::kInt32x4WithFlagX:
       __ LoadImmediate(temp, Immediate(0xFFFFFFFF), PP);
       __ movl(Address(RSP, 0), temp);
@@ skipping 34 matching lines @@
   __ AddImmediate(RSP, Immediate(16), PP);
 }
 
 
 LocationSummary* Int32x4ToFloat32x4Instr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 1;
   const intptr_t kNumTemps = 0;
   LocationSummary* summary =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
   summary->set_in(0, Location::RequiresFpuRegister());
-  summary->set_out(Location::SameAsFirstInput());
+  summary->set_out(0, Location::SameAsFirstInput());
   return summary;
 }
 
 
 void Int32x4ToFloat32x4Instr::EmitNativeCode(FlowGraphCompiler* compiler) {
   // NOP.
 }
 
 
 LocationSummary* BinaryInt32x4OpInstr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 2;
   const intptr_t kNumTemps = 0;
   LocationSummary* summary =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
   summary->set_in(0, Location::RequiresFpuRegister());
   summary->set_in(1, Location::RequiresFpuRegister());
-  summary->set_out(Location::SameAsFirstInput());
+  summary->set_out(0, Location::SameAsFirstInput());
   return summary;
 }
 
 
 void BinaryInt32x4OpInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   XmmRegister left = locs()->in(0).fpu_reg();
   XmmRegister right = locs()->in(1).fpu_reg();
-  ASSERT(left == locs()->out().fpu_reg());
+  ASSERT(left == locs()->out(0).fpu_reg());
   switch (op_kind()) {
     case Token::kBIT_AND: {
       __ andps(left, right);
       break;
     }
     case Token::kBIT_OR: {
       __ orps(left, right);
       break;
     }
     case Token::kBIT_XOR: {
@@ skipping 19 matching lines @@
     // currently we can't specify these registers because ParallelMoveResolver
     // assumes that XMM0 is free at all times.
     // TODO(vegorov): allow XMM0 to be used.
     const intptr_t kNumTemps = 1;
     LocationSummary* summary =
         new LocationSummary(InputCount(), kNumTemps, LocationSummary::kCall);
     summary->set_in(0, Location::FpuRegisterLocation(XMM1));
     // R13 is chosen because it is callee saved so we do not need to back it
     // up before calling into the runtime.
     summary->set_temp(0, Location::RegisterLocation(R13));
-    summary->set_out(Location::FpuRegisterLocation(XMM1));
+    summary->set_out(0, Location::FpuRegisterLocation(XMM1));
     return summary;
   }
   ASSERT(kind() == MethodRecognizer::kMathSqrt);
   const intptr_t kNumInputs = 1;
   const intptr_t kNumTemps = 0;
   LocationSummary* summary =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
   summary->set_in(0, Location::RequiresFpuRegister());
-  summary->set_out(Location::RequiresFpuRegister());
+  summary->set_out(0, Location::RequiresFpuRegister());
   return summary;
 }
 
 
 void MathUnaryInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   if (kind() == MethodRecognizer::kMathSqrt) {
-    __ sqrtsd(locs()->out().fpu_reg(), locs()->in(0).fpu_reg());
+    __ sqrtsd(locs()->out(0).fpu_reg(), locs()->in(0).fpu_reg());
   } else {
     ASSERT((kind() == MethodRecognizer::kMathSin) ||
            (kind() == MethodRecognizer::kMathCos));
     // Save RSP.
     __ movq(locs()->temp(0).reg(), RSP);
     __ ReserveAlignedFrameSpace(0);
     __ movaps(XMM0, locs()->in(0).fpu_reg());
     __ CallRuntime(TargetFunction(), InputCount());
-    __ movaps(locs()->out().fpu_reg(), XMM0);
+    __ movaps(locs()->out(0).fpu_reg(), XMM0);
     // Restore RSP.
     __ movq(RSP, locs()->temp(0).reg());
   }
 }
 
 
 LocationSummary* UnarySmiOpInstr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 1;
   return LocationSummary::Make(kNumInputs,
                                Location::SameAsFirstInput(),
                                LocationSummary::kNoCall);
 }
 
 
 void UnarySmiOpInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   Register value = locs()->in(0).reg();
-  ASSERT(value == locs()->out().reg());
+  ASSERT(value == locs()->out(0).reg());
   switch (op_kind()) {
     case Token::kNEGATE: {
       Label* deopt = compiler->AddDeoptStub(deopt_id(),
                                             kDeoptUnaryOp);
       __ negq(value);
       __ j(OVERFLOW, deopt);
       if (FLAG_throw_on_javascript_int_overflow) {
         EmitJavascriptOverflowCheck(compiler, range(), deopt, value);
       }
       break;
     }
     case Token::kBIT_NOT:
       __ notq(value);
       // Remove inverted smi-tag.
       __ AndImmediate(value, Immediate(~kSmiTagMask), PP);
       break;
     default:
       UNREACHABLE();
   }
 }
 
 
 LocationSummary* UnaryDoubleOpInstr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 1;
   const intptr_t kNumTemps = 0;
   LocationSummary* summary =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
   summary->set_in(0, Location::RequiresFpuRegister());
-  summary->set_out(Location::SameAsFirstInput());
+  summary->set_out(0, Location::SameAsFirstInput());
   return summary;
 }
 
 
 void UnaryDoubleOpInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   XmmRegister value = locs()->in(0).fpu_reg();
-  ASSERT(locs()->out().fpu_reg() == value);
+  ASSERT(locs()->out(0).fpu_reg() == value);
   __ DoubleNegate(value);
 }
 
 
 LocationSummary* MathMinMaxInstr::MakeLocationSummary(bool opt) const {
   if (result_cid() == kDoubleCid) {
     const intptr_t kNumInputs = 2;
     const intptr_t kNumTemps = 1;
     LocationSummary* summary =
         new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
     summary->set_in(0, Location::RequiresFpuRegister());
     summary->set_in(1, Location::RequiresFpuRegister());
     // Reuse the left register so that code can be made shorter.
-    summary->set_out(Location::SameAsFirstInput());
+    summary->set_out(0, Location::SameAsFirstInput());
     summary->set_temp(0, Location::RequiresRegister());
     return summary;
   }
   ASSERT(result_cid() == kSmiCid);
   const intptr_t kNumInputs = 2;
   const intptr_t kNumTemps = 0;
   LocationSummary* summary =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
   summary->set_in(0, Location::RequiresRegister());
   summary->set_in(1, Location::RequiresRegister());
   // Reuse the left register so that code can be made shorter.
-  summary->set_out(Location::SameAsFirstInput());
+  summary->set_out(0, Location::SameAsFirstInput());
   return summary;
 }
 
 
 void MathMinMaxInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   ASSERT((op_kind() == MethodRecognizer::kMathMin) ||
          (op_kind() == MethodRecognizer::kMathMax));
   const intptr_t is_min = (op_kind() == MethodRecognizer::kMathMin);
   if (result_cid() == kDoubleCid) {
     Label done, returns_nan, are_equal;
     XmmRegister left = locs()->in(0).fpu_reg();
     XmmRegister right = locs()->in(1).fpu_reg();
-    XmmRegister result = locs()->out().fpu_reg();
+    XmmRegister result = locs()->out(0).fpu_reg();
     Register temp = locs()->temp(0).reg();
     __ comisd(left, right);
     __ j(PARITY_EVEN, &returns_nan, Assembler::kNearJump);
     __ j(EQUAL, &are_equal, Assembler::kNearJump);
     const Condition double_condition =
         is_min ? TokenKindToDoubleCondition(Token::kLT)
                : TokenKindToDoubleCondition(Token::kGT);
     ASSERT(left == result);
     __ j(double_condition, &done, Assembler::kNearJump);
     __ movsd(result, right);
@@ skipping 23 matching lines @@
       __ j(ZERO, &done, Assembler::kNearJump);  // Positive -> return left.
     }
     __ movsd(result, right);
     __ Bind(&done);
     return;
   }
 
   ASSERT(result_cid() == kSmiCid);
   Register left = locs()->in(0).reg();
   Register right = locs()->in(1).reg();
-  Register result = locs()->out().reg();
+  Register result = locs()->out(0).reg();
   __ cmpq(left, right);
   ASSERT(result == left);
   if (is_min) {
     __ cmovgeq(result, right);
   } else {
     __ cmovlessq(result, right);
   }
 }
 
 
 LocationSummary* SmiToDoubleInstr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 1;
   const intptr_t kNumTemps = 0;
   LocationSummary* result =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
   result->set_in(0, Location::WritableRegister());
-  result->set_out(Location::RequiresFpuRegister());
+  result->set_out(0, Location::RequiresFpuRegister());
   return result;
 }
 
 
 void SmiToDoubleInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   Register value = locs()->in(0).reg();
-  FpuRegister result = locs()->out().fpu_reg();
+  FpuRegister result = locs()->out(0).fpu_reg();
   __ SmiUntag(value);
   __ cvtsi2sd(result, value);
 }
 
 
 LocationSummary* DoubleToIntegerInstr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 1;
   const intptr_t kNumTemps = 1;
   LocationSummary* result =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kCall);
   result->set_in(0, Location::RegisterLocation(RCX));
-  result->set_out(Location::RegisterLocation(RAX));
+  result->set_out(0, Location::RegisterLocation(RAX));
   result->set_temp(0, Location::RegisterLocation(RBX));
   return result;
 }
 
 
 void DoubleToIntegerInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
-  Register result = locs()->out().reg();
+  Register result = locs()->out(0).reg();
   Register value_obj = locs()->in(0).reg();
   Register temp = locs()->temp(0).reg();
   XmmRegister value_double = XMM0;
   ASSERT(result == RAX);
   ASSERT(result != value_obj);
   ASSERT(result != temp);
   __ movsd(value_double, FieldAddress(value_obj, Double::value_offset()));
   __ cvttsd2siq(result, value_double);
   // Overflow is signalled with minint.
   Label do_call, done;
@@ skipping 23 matching lines @@
   __ Bind(&done);
 }
 
 
 LocationSummary* DoubleToSmiInstr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 1;
   const intptr_t kNumTemps = 1;
   LocationSummary* result = new LocationSummary(
       kNumInputs, kNumTemps, LocationSummary::kNoCall);
   result->set_in(0, Location::RequiresFpuRegister());
-  result->set_out(Location:: Location::RequiresRegister());
+  result->set_out(0, Location:: Location::RequiresRegister());
   result->set_temp(0, Location::RequiresRegister());
   return result;
 }
 
 
 void DoubleToSmiInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   Label* deopt = compiler->AddDeoptStub(deopt_id(), kDeoptDoubleToSmi);
-  Register result = locs()->out().reg();
+  Register result = locs()->out(0).reg();
   XmmRegister value = locs()->in(0).fpu_reg();
   Register temp = locs()->temp(0).reg();
 
   __ cvttsd2siq(result, value);
   // Overflow is signalled with minint.
   Label do_call, done;
   // Check for overflow and that it fits into Smi.
   __ movq(temp, result);
   __ shlq(temp, Immediate(1));
   __ j(OVERFLOW, deopt);
   __ SmiTag(result);
   if (FLAG_throw_on_javascript_int_overflow) {
     EmitJavascriptOverflowCheck(compiler, range(), deopt, result);
   }
 }
 
 
 LocationSummary* DoubleToDoubleInstr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 1;
   const intptr_t kNumTemps = 0;
   LocationSummary* result =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
   result->set_in(0, Location::RequiresFpuRegister());
-  result->set_out(Location::RequiresFpuRegister());
+  result->set_out(0, Location::RequiresFpuRegister());
   return result;
 }
 
 
 void DoubleToDoubleInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   XmmRegister value = locs()->in(0).fpu_reg();
-  XmmRegister result = locs()->out().fpu_reg();
+  XmmRegister result = locs()->out(0).fpu_reg();
   switch (recognized_kind()) {
     case MethodRecognizer::kDoubleTruncate:
       __ roundsd(result, value,  Assembler::kRoundToZero);
       break;
     case MethodRecognizer::kDoubleFloor:
       __ roundsd(result, value,  Assembler::kRoundDown);
       break;
     case MethodRecognizer::kDoubleCeil:
       __ roundsd(result, value,  Assembler::kRoundUp);
       break;
     default:
       UNREACHABLE();
   }
 }
 
 
 LocationSummary* DoubleToFloatInstr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 1;
   const intptr_t kNumTemps = 0;
   LocationSummary* result =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
   result->set_in(0, Location::RequiresFpuRegister());
-  result->set_out(Location::SameAsFirstInput());
+  result->set_out(0, Location::SameAsFirstInput());
   return result;
 }
 
 
 void DoubleToFloatInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
-  __ cvtsd2ss(locs()->out().fpu_reg(), locs()->in(0).fpu_reg());
+  __ cvtsd2ss(locs()->out(0).fpu_reg(), locs()->in(0).fpu_reg());
 }
 
 
 LocationSummary* FloatToDoubleInstr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 1;
   const intptr_t kNumTemps = 0;
   LocationSummary* result =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
   result->set_in(0, Location::RequiresFpuRegister());
-  result->set_out(Location::SameAsFirstInput());
+  result->set_out(0, Location::SameAsFirstInput());
   return result;
 }
 
 
 void FloatToDoubleInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
-  __ cvtss2sd(locs()->out().fpu_reg(), locs()->in(0).fpu_reg());
+  __ cvtss2sd(locs()->out(0).fpu_reg(), locs()->in(0).fpu_reg());
 }
 
 
 LocationSummary* InvokeMathCFunctionInstr::MakeLocationSummary(bool opt) const {
   // Calling convention on x64 uses XMM0 and XMM1 to pass the first two
   // double arguments and XMM0 to return the result. Unfortunately
   // currently we can't specify these registers because ParallelMoveResolver
   // assumes that XMM0 is free at all times.
   // TODO(vegorov): allow XMM0 to be used.
   ASSERT((InputCount() == 1) || (InputCount() == 2));
   const intptr_t kNumTemps = 1;
   LocationSummary* result =
       new LocationSummary(InputCount(), kNumTemps, LocationSummary::kCall);
   result->set_temp(0, Location::RegisterLocation(R13));
   result->set_in(0, Location::FpuRegisterLocation(XMM2));
   if (InputCount() == 2) {
     result->set_in(1, Location::FpuRegisterLocation(XMM1));
   }
   if (recognized_kind() == MethodRecognizer::kMathDoublePow) {
     // Temp index 1.
     result->AddTemp(Location::RegisterLocation(RAX));
     // Temp index 2.
     result->AddTemp(Location::FpuRegisterLocation(XMM4));
   }
-  result->set_out(Location::FpuRegisterLocation(XMM3));
+  result->set_out(0, Location::FpuRegisterLocation(XMM3));
   return result;
 }
 
 
 void InvokeMathCFunctionInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   // Save RSP.
   __ movq(locs()->temp(kSavedSpTempIndex).reg(), RSP);
   __ ReserveAlignedFrameSpace(0);
   __ movaps(XMM0, locs()->in(0).fpu_reg());
   if (InputCount() == 2) {
     ASSERT(locs()->in(1).fpu_reg() == XMM1);
   }
   // For pow-function return NaN if exponent is NaN.
   Label do_call, skip_call;
   if (recognized_kind() == MethodRecognizer::kMathDoublePow) {
     // Pseudo code:
     // if (exponent == 0.0) return 0.0;
     // if (base == 1.0) return 1.0;
     // if (base.isNaN || exponent.isNaN) {
     //    return double.NAN;
     // }
     XmmRegister base = locs()->in(0).fpu_reg();
     XmmRegister exp = locs()->in(1).fpu_reg();
-    XmmRegister result = locs()->out().fpu_reg();
+    XmmRegister result = locs()->out(0).fpu_reg();
     Register temp = locs()->temp(kObjectTempIndex).reg();
     XmmRegister zero_temp = locs()->temp(kDoubleTempIndex).fpu_reg();
 
     // Check if exponent is 0.0 -> return 1.0;
     __ LoadObject(temp, Double::ZoneHandle(Double::NewCanonical(0)), PP);
     __ movsd(zero_temp, FieldAddress(temp, Double::value_offset()));
     __ LoadObject(temp, Double::ZoneHandle(Double::NewCanonical(1)), PP);
     __ movsd(result, FieldAddress(temp, Double::value_offset()));
     // 'result' contains 1.0.
     Label exp_is_nan;
@@ skipping 16 matching lines @@
     __ Bind(&exp_is_nan);
     // Checks if base == 1.0.
     __ comisd(base, result);
     __ j(PARITY_EVEN, &base_is_nan, Assembler::kNearJump);
     __ j(EQUAL, &skip_call, Assembler::kNearJump);  // base and result are 1.0
     __ movsd(result, exp);  // result is NaN
     __ jmp(&skip_call, Assembler::kNearJump);
   }
   __ Bind(&do_call);
   __ CallRuntime(TargetFunction(), InputCount());
-  __ movaps(locs()->out().fpu_reg(), XMM0);
+  __ movaps(locs()->out(0).fpu_reg(), XMM0);
   __ Bind(&skip_call);
   // Restore RSP.
   __ movq(RSP, locs()->temp(kSavedSpTempIndex).reg());
 }
 
 
 LocationSummary* MergedMathInstr::MakeLocationSummary(bool opt) const {
   if (kind() == MergedMathInstr::kTruncDivMod) {
     const intptr_t kNumInputs = 2;
     const intptr_t kNumTemps = 1;
     LocationSummary* summary =
         new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
     // Both inputs must be writable because they will be untagged.
     summary->set_in(0, Location::RegisterLocation(RAX));
     summary->set_in(1, Location::WritableRegister());
-    summary->set_out(Location::RequiresRegister());
+    summary->set_out(0, Location::RequiresRegister());
     // Will be used for sign extension and division.
     summary->set_temp(0, Location::RegisterLocation(RDX));
     return summary;
   }
   if (kind() == MergedMathInstr::kSinCos) {
     const intptr_t kNumInputs = 1;
     const intptr_t kNumTemps = 1;
     LocationSummary* summary =
         new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kCall);
     summary->set_in(0, Location::FpuRegisterLocation(XMM1));
     // R13 is chosen because it is callee saved so we do not need to back it
     // up before calling into the runtime.
     summary->set_temp(0, Location::RegisterLocation(R13));
-    summary->set_out(Location::RegisterLocation(RAX));
+    summary->set_out(0, Location::RegisterLocation(RAX));
     return summary;
   }
   UNIMPLEMENTED();
   return NULL;
 }
 
 
 
 typedef void (*SinCosCFunction) (double x, double* res_sin, double* res_cos);
 
 extern const RuntimeEntry kSinCosRuntimeEntry(
     "libc_sincos", reinterpret_cast<RuntimeFunction>(
         static_cast<SinCosCFunction>(&SinCos)), 1, true, true);
 
 
 void MergedMathInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   Label* deopt = NULL;
   if (CanDeoptimize()) {
     deopt  = compiler->AddDeoptStub(deopt_id(), kDeoptBinarySmiOp);
   }
   if (kind() == MergedMathInstr::kTruncDivMod) {
     Register left = locs()->in(0).reg();
     Register right = locs()->in(1).reg();
-    Register result = locs()->out().reg();
+    Register result = locs()->out(0).reg();
     Label not_32bit, done;
     Register temp = locs()->temp(0).reg();
     ASSERT(left == RAX);
     ASSERT((right != RDX) && (right != RAX));
     ASSERT(temp == RDX);
     ASSERT((result != RDX) && (result != RAX));
 
     Range* right_range = InputAt(1)->definition()->range();
     if ((right_range == NULL) || right_range->Overlaps(0, 0)) {
       // Handle divide by zero in runtime.
@@ skipping 104 matching lines @@
     __ leaq(RDI, Address(RSP, 2 * kWordSize + kDoubleSize));
     __ leaq(RSI, Address(RSP, 2 * kWordSize + 2 * kDoubleSize));
     __ movaps(XMM0, locs()->in(0).fpu_reg());
 
     __ CallRuntime(kSinCosRuntimeEntry, InputCount());
     __ movsd(XMM0, Address(RSP, 2 * kWordSize + kDoubleSize * 2));  // sin.
     __ movsd(XMM1, Address(RSP, 2 * kWordSize + kDoubleSize));  // cos.
     // Restore RSP.
     __ movq(RSP, locs()->temp(0).reg());
 
-    Register result = locs()->out().reg();
+    Register result = locs()->out(0).reg();
     const TypedData& res_array = TypedData::ZoneHandle(
       TypedData::New(kTypedDataFloat64ArrayCid, 2, Heap::kOld));
     __ LoadObject(result, res_array, PP);
     const intptr_t index_scale =
         FlowGraphCompiler::ElementSizeFor(kTypedDataFloat64ArrayCid);
     Address sin_address(
         FlowGraphCompiler::ElementAddressForIntIndex(
             kTypedDataFloat64ArrayCid, index_scale, result,
             MergedMathInstr::ResultIndexOf(MethodRecognizer::kMathSin)));
     Address cos_address(
@@ skipping 46 matching lines @@
                             deopt,
                             deopt_id(),
                             instance_call()->token_pos(),
                             locs());
 }
 
 
 LocationSummary* BranchInstr::MakeLocationSummary(bool opt) const {
   comparison()->InitializeLocationSummary(opt);
   // Branches don't produce a result.
-  comparison()->locs()->set_out(Location::NoLocation());
+  comparison()->locs()->set_out(0, Location::NoLocation());
   return comparison()->locs();
 }
 
 
 void BranchInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   comparison()->EmitBranchCode(compiler, this);
 }
 
 
 LocationSummary* CheckClassInstr::MakeLocationSummary(bool opt) const {
@@ skipping 269 matching lines @@
 
 
 LocationSummary* CurrentContextInstr::MakeLocationSummary(bool opt) const {
   return LocationSummary::Make(0,
                                Location::RequiresRegister(),
                                LocationSummary::kNoCall);
 }
 
 
 void CurrentContextInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
-  __ MoveRegister(locs()->out().reg(), CTX);
+  __ MoveRegister(locs()->out(0).reg(), CTX);
 }
 
 
 LocationSummary* StrictCompareInstr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 2;
   const intptr_t kNumTemps = 0;
   if (needs_number_check()) {
     LocationSummary* locs =
         new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kCall);
     locs->set_in(0, Location::RegisterLocation(RAX));
     locs->set_in(1, Location::RegisterLocation(RCX));
-    locs->set_out(Location::RegisterLocation(RAX));
+    locs->set_out(0, Location::RegisterLocation(RAX));
     return locs;
   }
   LocationSummary* locs =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
   locs->set_in(0, Location::RegisterOrConstant(left()));
   // Only one of the inputs can be a constant. Choose register if the first one
   // is a constant.
   locs->set_in(1, locs->in(0).IsConstant()
                       ? Location::RequiresRegister()
                       : Location::RegisterOrConstant(right()));
-  locs->set_out(Location::RequiresRegister());
+  locs->set_out(0, Location::RequiresRegister());
   return locs;
 }
 
 
 Condition StrictCompareInstr::EmitComparisonCode(FlowGraphCompiler* compiler,
                                                  BranchLabels labels) {
   Location left = locs()->in(0);
   Location right = locs()->in(1);
   ASSERT(!left.IsConstant() || !right.IsConstant());
   if (left.IsConstant()) {
@@ skipping 20 matching lines @@
 
 void StrictCompareInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   ASSERT(kind() == Token::kEQ_STRICT || kind() == Token::kNE_STRICT);
 
   Label is_true, is_false;
   BranchLabels labels = { &is_true, &is_false, &is_false };
 
   Condition true_condition = EmitComparisonCode(compiler, labels);
   EmitBranchOnCondition(compiler, true_condition, labels);
 
-  Register result = locs()->out().reg();
+  Register result = locs()->out(0).reg();
   Label done;
   __ Bind(&is_false);
   __ LoadObject(result, Bool::False(), PP);
   __ jmp(&done);
   __ Bind(&is_true);
   __ LoadObject(result, Bool::True(), PP);
   __ Bind(&done);
 }
 
 
 void StrictCompareInstr::EmitBranchCode(FlowGraphCompiler* compiler,
                                         BranchInstr* branch) {
   ASSERT(kind() == Token::kEQ_STRICT || kind() == Token::kNE_STRICT);
 
   BranchLabels labels = compiler->CreateBranchLabels(branch);
   Condition true_condition = EmitComparisonCode(compiler, labels);
   EmitBranchOnCondition(compiler, true_condition, labels);
 }
 
 
 LocationSummary* ClosureCallInstr::MakeLocationSummary(bool opt) const {
   const intptr_t kNumInputs = 0;
   const intptr_t kNumTemps = 1;
   LocationSummary* result =
       new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kCall);
-  result->set_out(Location::RegisterLocation(RAX));
+  result->set_out(0, Location::RegisterLocation(RAX));
   result->set_temp(0, Location::RegisterLocation(R10));  // Arg. descriptor.
   return result;
 }
 
 
 void ClosureCallInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   // The arguments to the stub include the closure, as does the arguments
   // descriptor.
   Register temp_reg = locs()->temp(0).reg();
   int argument_count = ArgumentCount();
@@ skipping 13 matching lines @@
 
 LocationSummary* BooleanNegateInstr::MakeLocationSummary(bool opt) const {
   return LocationSummary::Make(1,
                                Location::RequiresRegister(),
                                LocationSummary::kNoCall);
 }
 
 
 void BooleanNegateInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   Register value = locs()->in(0).reg();
-  Register result = locs()->out().reg();
+  Register result = locs()->out(0).reg();
 
   Label done;
   __ LoadObject(result, Bool::True(), PP);
   __ CompareRegisters(result, value);
   __ j(NOT_EQUAL, &done, Assembler::kNearJump);
   __ LoadObject(result, Bool::False(), PP);
   __ Bind(&done);
 }
 
 
@@ skipping 10 matching lines @@
                          PcDescriptors::kOther,
                          locs());
   __ Drop(ArgumentCount());  // Discard arguments.
 }
 
 }  // namespace dart
 
 #undef __
 
 #endif  // defined TARGET_ARCH_X64