Change == into an instance call to allow polymorphic inlining of ==.

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 389 matching lines @@
     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());
     return locs;
   }
-  if (IsCheckedStrictEqual()) {
-    const intptr_t kNumTemps = 1;
-    LocationSummary* locs =
-        new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kNoCall);
-    locs->set_in(0, Location::RequiresRegister());
-    locs->set_in(1, Location::RequiresRegister());
-    locs->set_temp(0, Location::RequiresRegister());
-    locs->set_out(Location::RequiresRegister());
-    return locs;
-  }
-  if (IsPolymorphic()) {
-    const intptr_t kNumTemps = 1;
-    LocationSummary* locs =
-        new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kCall);
-    locs->set_in(0, Location::RegisterLocation(RCX));
-    locs->set_in(1, Location::RegisterLocation(RDX));
-    locs->set_temp(0, Location::RegisterLocation(RBX));
-    locs->set_out(Location::RegisterLocation(RAX));
-    return locs;
-  }
-  const intptr_t kNumTemps = 1;
-  LocationSummary* locs =
-      new LocationSummary(kNumInputs, kNumTemps, LocationSummary::kCall);
-  locs->set_in(0, Location::RegisterLocation(RCX));
-  locs->set_in(1, Location::RegisterLocation(RDX));
-  locs->set_temp(0, Location::RegisterLocation(RBX));
-  locs->set_out(Location::RegisterLocation(RAX));
-  return locs;
-}
-
-
-static void EmitEqualityAsInstanceCall(FlowGraphCompiler* compiler,
-                                       intptr_t deopt_id,
-                                       intptr_t token_pos,
-                                       Token::Kind kind,
-                                       LocationSummary* locs,
-                                       const ICData& original_ic_data) {
-  if (!compiler->is_optimizing()) {
-    compiler->AddCurrentDescriptor(PcDescriptors::kDeopt,
-                                   deopt_id,
-                                   token_pos);
-  }
-  const int kNumberOfArguments = 2;
-  const Array& kNoArgumentNames = Object::null_array();
-  const int kNumArgumentsChecked = 2;
-
-  ICData& equality_ic_data = ICData::ZoneHandle(original_ic_data.raw());
-  if (compiler->is_optimizing() && FLAG_propagate_ic_data) {
-    ASSERT(!original_ic_data.IsNull());
-    if (original_ic_data.NumberOfChecks() == 0) {
-      // IC call for reoptimization populates original ICData.
-      equality_ic_data = original_ic_data.raw();
-    } else {
-      // Megamorphic call.
-      equality_ic_data = original_ic_data.AsUnaryClassChecks();
-    }
-  } else {
-    const Array& arguments_descriptor =
-        Array::Handle(ArgumentsDescriptor::New(kNumberOfArguments,
-                                               kNoArgumentNames));
-    equality_ic_data = ICData::New(compiler->parsed_function().function(),
-                                   Symbols::EqualOperator(),
-                                   arguments_descriptor,
-                                   deopt_id,
-                                   kNumArgumentsChecked);
-  }
-  compiler->GenerateInstanceCall(deopt_id,
-                                 token_pos,
-                                 kNumberOfArguments,
-                                 kNoArgumentNames,
-                                 locs,
-                                 equality_ic_data);
-  if (kind == Token::kNE) {
-    Label true_label, done;
-    // Negate the condition: true label returns false and vice versa.
-    __ CompareObject(RAX, Bool::True(), PP);
-    __ j(EQUAL, &true_label, Assembler::kNearJump);
-    __ LoadObject(RAX, Bool::True(), PP);
-    __ jmp(&done, Assembler::kNearJump);
-    __ Bind(&true_label);
-    __ LoadObject(RAX, Bool::False(), PP);
-    __ Bind(&done);
-  }
+  UNREACHABLE();
+  return NULL;
 }
 
 
 static void LoadValueCid(FlowGraphCompiler* compiler,
                          Register value_cid_reg,
                          Register value_reg,
                          Label* value_is_smi = NULL) {
   Label done;
   if (value_is_smi == NULL) {
     __ LoadImmediate(value_cid_reg, Immediate(kSmiCid), PP);
   }
   __ testq(value_reg, Immediate(kSmiTagMask));
   if (value_is_smi == NULL) {
     __ j(ZERO, &done, Assembler::kNearJump);
   } else {
     __ j(ZERO, value_is_smi);
   }
   __ LoadClassId(value_cid_reg, value_reg);
   __ Bind(&done);
 }
 
 
-static void EmitEqualityAsPolymorphicCall(FlowGraphCompiler* compiler,
-                                          const ICData& orig_ic_data,
-                                          LocationSummary* locs,
-                                          BranchInstr* branch,
-                                          Token::Kind kind,
-                                          intptr_t deopt_id,
-                                          intptr_t token_pos) {
-  ASSERT((kind == Token::kEQ) || (kind == Token::kNE));
-  const ICData& ic_data = ICData::Handle(orig_ic_data.AsUnaryClassChecks());
-  ASSERT(ic_data.NumberOfChecks() > 0);
-  ASSERT(ic_data.num_args_tested() == 1);
-  Label* deopt = compiler->AddDeoptStub(deopt_id, kDeoptEquality);
-  Register left = locs->in(0).reg();
-  Register right = locs->in(1).reg();
-  Register temp = locs->temp(0).reg();
-  LoadValueCid(compiler, temp, left,
-               (ic_data.GetReceiverClassIdAt(0) == kSmiCid) ? NULL : deopt);
-  // 'temp' contains class-id of the left argument.
-  ObjectStore* object_store = Isolate::Current()->object_store();
-  Condition cond = TokenKindToSmiCondition(kind);
-  Label done;
-  const intptr_t len = ic_data.NumberOfChecks();
-  for (intptr_t i = 0; i < len; i++) {
-    // Assert that the Smi is at position 0, if at all.
-    ASSERT((ic_data.GetReceiverClassIdAt(i) != kSmiCid) || (i == 0));
-    Label next_test;
-    __ CompareImmediate(temp, Immediate(ic_data.GetReceiverClassIdAt(i)), PP);
-    if (i < len - 1) {
-      __ j(NOT_EQUAL, &next_test);
-    } else {
-      __ j(NOT_EQUAL, deopt);
-    }
-    const Function& target = Function::ZoneHandle(ic_data.GetTargetAt(i));
-    if (target.Owner() == object_store->object_class()) {
-      // Object.== is same as ===.
-      __ Drop(2);
-      __ cmpq(left, right);
-      if (branch != NULL) {
-        branch->EmitBranchOnCondition(compiler, cond);
-      } else {
-        // This case should be rare.
-        Register result = locs->out().reg();
-        Label load_true;
-        __ j(cond, &load_true, Assembler::kNearJump);
-        __ LoadObject(result, Bool::False(), PP);
-        __ jmp(&done);
-        __ Bind(&load_true);
-        __ LoadObject(result, Bool::True(), PP);
-      }
-    } else {
-      const int kNumberOfArguments = 2;
-      const Array& kNoArgumentNames = Object::null_array();
-      compiler->GenerateStaticCall(deopt_id,
-                                   token_pos,
-                                   target,
-                                   kNumberOfArguments,
-                                   kNoArgumentNames,
-                                   locs);
-      if (branch == NULL) {
-        if (kind == Token::kNE) {
-          Label false_label;
-          __ CompareObject(RAX, Bool::True(), PP);
-          __ j(EQUAL, &false_label, Assembler::kNearJump);
-          __ LoadObject(RAX, Bool::True(), PP);
-          __ jmp(&done);
-          __ Bind(&false_label);
-          __ LoadObject(RAX, Bool::False(), PP);
-        }
-      } else {
-        if (branch->is_checked()) {
-          EmitAssertBoolean(RAX, token_pos, deopt_id, locs, compiler);
-        }
-        __ CompareObject(RAX, Bool::True(), PP);
-        branch->EmitBranchOnCondition(compiler, cond);
-      }
-    }
-    if (i < len - 1) {
-      __ jmp(&done);
-      __ Bind(&next_test);
-    }
-  }
-  __ Bind(&done);
-}
-
-
-// Emit code when ICData's targets are all Object == (which is ===).
-static void EmitCheckedStrictEqual(FlowGraphCompiler* compiler,
-                                   const ICData& orig_ic_data,
-                                   const LocationSummary& locs,
-                                   Token::Kind kind,
-                                   BranchInstr* branch,
-                                   intptr_t deopt_id) {
-  ASSERT((kind == Token::kEQ) || (kind == Token::kNE));
-  Register left = locs.in(0).reg();
-  Register right = locs.in(1).reg();
-  Register temp = locs.temp(0).reg();
-  Label* deopt = compiler->AddDeoptStub(deopt_id, kDeoptEquality);
-  __ testq(left, Immediate(kSmiTagMask));
-  __ j(ZERO, deopt);
-  // 'left' is not Smi.
-
-  Label identity_compare;
-  __ CompareObject(right, Object::null_object(), PP);
-  __ j(EQUAL, &identity_compare);
-  __ CompareObject(left, Object::null_object(), PP);
-  __ j(EQUAL, &identity_compare);
-
-  __ LoadClassId(temp, left);
-  const ICData& ic_data = ICData::Handle(orig_ic_data.AsUnaryClassChecks());
-  const intptr_t len = ic_data.NumberOfChecks();
-  for (intptr_t i = 0; i < len; i++) {
-    __ CompareImmediate(temp, Immediate(ic_data.GetReceiverClassIdAt(i)), PP);
-    if (i == (len - 1)) {
-      __ j(NOT_EQUAL, deopt);
-    } else {
-      __ j(EQUAL, &identity_compare);
-    }
-  }
-  __ Bind(&identity_compare);
-  __ cmpq(left, right);
-  if (branch == NULL) {
-    Label done, is_equal;
-    Register result = locs.out().reg();
-    __ j(EQUAL, &is_equal, Assembler::kNearJump);
-    // Not equal.
-    __ LoadObject(result, Bool::Get(kind != Token::kEQ), PP);
-    __ jmp(&done, Assembler::kNearJump);
-    __ Bind(&is_equal);
-    __ LoadObject(result, Bool::Get(kind == Token::kEQ), PP);
-    __ Bind(&done);
-  } else {
-    Condition cond = TokenKindToSmiCondition(kind);
-    branch->EmitBranchOnCondition(compiler, cond);
-  }
-}
-
-
-// First test if receiver is NULL, in which case === is applied.
-// If type feedback was provided (lists of <class-id, target>), do a
-// type by type check (either === or static call to the operator.
-static void EmitGenericEqualityCompare(FlowGraphCompiler* compiler,
-                                       LocationSummary* locs,
-                                       Token::Kind kind,
-                                       BranchInstr* branch,
-                                       const ICData& ic_data,
-                                       intptr_t deopt_id,
-                                       intptr_t token_pos) {
-  ASSERT((kind == Token::kEQ) || (kind == Token::kNE));
-  ASSERT(!ic_data.IsNull() && (ic_data.NumberOfChecks() > 0));
-  Register left = locs->in(0).reg();
-  Register right = locs->in(1).reg();
-  __ pushq(left);
-  __ pushq(right);
-  EmitEqualityAsPolymorphicCall(compiler, ic_data, locs, branch, kind,
-                                deopt_id, token_pos);
-}
-
-
 static Condition FlipCondition(Condition condition) {
   switch (condition) {
     case EQUAL:         return EQUAL;
     case NOT_EQUAL:     return NOT_EQUAL;
     case LESS:          return GREATER;
     case LESS_EQUAL:    return GREATER_EQUAL;
     case GREATER:       return LESS;
     case GREATER_EQUAL: return LESS_EQUAL;
     case BELOW:         return ABOVE;
     case BELOW_EQUAL:   return ABOVE_EQUAL;
@@ skipping 81 matching lines @@
   if (operation_cid() == kSmiCid) {
     // Deoptimizes if both arguments not Smi.
     EmitSmiComparisonOp(compiler, *locs(), kind(), kNoBranch);
     return;
   }
   if (operation_cid() == kDoubleCid) {
     // Deoptimizes if both arguments are Smi, or if none is Double or Smi.
     EmitDoubleComparisonOp(compiler, *locs(), kind(), kNoBranch);
     return;
   }
-  if (IsCheckedStrictEqual()) {
-    EmitCheckedStrictEqual(compiler, *ic_data(), *locs(), kind(), kNoBranch,
-                           deopt_id());
-    return;
-  }
-  if (IsPolymorphic()) {
-    EmitGenericEqualityCompare(compiler, locs(), kind(), kNoBranch, *ic_data(),
-                               deopt_id(), token_pos());
-    return;
-  }
-  Register left = locs()->in(0).reg();
-  Register right = locs()->in(1).reg();
-  __ pushq(left);
-  __ pushq(right);
-  EmitEqualityAsInstanceCall(compiler,
-                             deopt_id(),
-                             token_pos(),
-                             kind(),
-                             locs(),
-                             *ic_data());
-  ASSERT(locs()->out().reg() == RAX);
+  UNREACHABLE();
 }
 
 
 void EqualityCompareInstr::EmitBranchCode(FlowGraphCompiler* compiler,
                                           BranchInstr* branch) {
   ASSERT((kind() == Token::kNE) || (kind() == Token::kEQ));
   if (operation_cid() == kSmiCid) {
     // Deoptimizes if both arguments not Smi.
     EmitSmiComparisonOp(compiler, *locs(), kind(), branch);
     return;
   }
   if (operation_cid() == kDoubleCid) {
     // Deoptimizes if both arguments are Smi, or if none is Double or Smi.
     EmitDoubleComparisonOp(compiler, *locs(), kind(), branch);
     return;
   }
-  if (IsCheckedStrictEqual()) {
-    EmitCheckedStrictEqual(compiler, *ic_data(), *locs(), kind(), branch,
-                           deopt_id());
-    return;
-  }
-  if (IsPolymorphic()) {
-    EmitGenericEqualityCompare(compiler, locs(), kind(), branch, *ic_data(),
-                               deopt_id(), token_pos());
-    return;
-  }
-  Register left = locs()->in(0).reg();
-  Register right = locs()->in(1).reg();
-  __ pushq(left);
-  __ pushq(right);
-  EmitEqualityAsInstanceCall(compiler,
-                             deopt_id(),
-                             token_pos(),
-                             Token::kEQ,  // kNE reverse occurs at branch.
-                             locs(),
-                             *ic_data());
-  if (branch->is_checked()) {
-    EmitAssertBoolean(RAX, token_pos(), deopt_id(), locs(), compiler);
-  }
-  Condition branch_condition = (kind() == Token::kNE) ? NOT_EQUAL : EQUAL;
-  __ CompareObject(RAX, Bool::True(), PP);
-  branch->EmitBranchOnCondition(compiler, branch_condition);
+  UNREACHABLE();
 }
 
 
 LocationSummary* RelationalOpInstr::MakeLocationSummary() 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());
@@ skipping 3960 matching lines @@
                          PcDescriptors::kOther,
                          locs());
   __ Drop(2);  // Discard type arguments and receiver.
 }
 
 }  // namespace dart
 
 #undef __
 
 #endif  // defined TARGET_ARCH_X64