VM: Improve receiver class check in polymorphic inlining.

runtime/vm/intermediate_language_arm.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_ARM.
 #if defined(TARGET_ARCH_ARM)
 
 #include "vm/intermediate_language.h"
 
 #include "vm/cpu.h"
@@ skipping 5668 matching lines @@
 
 
 void BranchInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   comparison()->EmitBranchCode(compiler, this);
 }
 
 
 LocationSummary* CheckClassInstr::MakeLocationSummary(Isolate* isolate,
                                                       bool opt) const {
   const intptr_t kNumInputs = 1;
-  const intptr_t kNumTemps = !IsNullCheck() ? 1 : 0;
+  const bool need_mask_temp = IsDenseSwitch() && !IsDenseMask(ComputeCidMask());
+  const intptr_t kNumTemps = !IsNullCheck() ? (need_mask_temp ? 2 : 1) : 0;
   LocationSummary* summary = new(isolate) LocationSummary(
       isolate, kNumInputs, kNumTemps, LocationSummary::kNoCall);
   summary->set_in(0, Location::RequiresRegister());
   if (!IsNullCheck()) {
     summary->set_temp(0, Location::RequiresRegister());
+    if (need_mask_temp) {
+      summary->set_temp(1, Location::RequiresRegister());
+    }
   }
   return summary;
 }
 
 
 void CheckClassInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   const ICData::DeoptReasonId deopt_reason = licm_hoisted_ ?
       ICData::kDeoptHoistedCheckClass : ICData::kDeoptCheckClass;
   if (IsNullCheck()) {
     Label* deopt = compiler->AddDeoptStub(deopt_id(), deopt_reason);
@@ skipping 12 matching lines @@
   intptr_t cix = 0;
   if (unary_checks().GetReceiverClassIdAt(cix) == kSmiCid) {
     __ tst(value, Operand(kSmiTagMask));
     __ b(&is_ok, EQ);
     cix++;  // Skip first check.
   } else {
     __ tst(value, Operand(kSmiTagMask));
     __ b(deopt, EQ);
   }
   __ LoadClassId(temp, value);
-  const intptr_t num_checks = unary_checks().NumberOfChecks();
-  for (intptr_t i = cix; i < num_checks; i++) {
-    ASSERT(unary_checks().GetReceiverClassIdAt(i) != kSmiCid);
-    __ CompareImmediate(temp, unary_checks().GetReceiverClassIdAt(i));
-    if (i == (num_checks - 1)) {
-      __ b(deopt, NE);
-    } else {
-      __ b(&is_ok, EQ);
+
+  if (IsDenseSwitch()) {
+    ASSERT(cids_[0] < cids_[cids_.length() - 1]);
+    __ AddImmediate(temp, -cids_[0]);
+    __ CompareImmediate(temp, cids_[cids_.length() - 1] - cids_[0]);
+    __ b(deopt, HI);
+
+    intptr_t mask = ComputeCidMask();
+    if (!IsDenseMask(mask)) {
+      // Only need mask if there are missing numbers in the range.
+      ASSERT(cids_.length() > 2);
+      Register mask_reg = locs()->temp(1).reg();
+      __ LoadImmediate(mask_reg, 1);
+      __ Lsl(mask_reg, mask_reg, temp);
+      __ TestImmediate(mask_reg, mask);
+      __ b(deopt, EQ);
+    }
+  } else {
+    const intptr_t num_checks = unary_checks().NumberOfChecks();
+    for (intptr_t i = cix; i < num_checks; i++) {
+      ASSERT(unary_checks().GetReceiverClassIdAt(i) != kSmiCid);
+      __ CompareImmediate(temp, unary_checks().GetReceiverClassIdAt(i));
+      if (i == (num_checks - 1)) {
+        __ b(deopt, NE);
+      } else {
+        __ b(&is_ok, EQ);
+      }
     }
   }
   __ Bind(&is_ok);
 }
 
 
 LocationSummary* CheckSmiInstr::MakeLocationSummary(Isolate* isolate,
                                                     bool opt) const {
   const intptr_t kNumInputs = 1;
   const intptr_t kNumTemps = 0;
   LocationSummary* summary = new(isolate) LocationSummary(
       isolate, kNumInputs, kNumTemps, LocationSummary::kNoCall);
   summary->set_in(0, Location::RequiresRegister());
   return summary;
 }
 
 
 void CheckSmiInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   const Register value = locs()->in(0).reg();
   Label* deopt = compiler->AddDeoptStub(deopt_id(), ICData::kDeoptCheckSmi);
   __ tst(value, Operand(kSmiTagMask));
   __ b(deopt, NE);
 }
 
 
+LocationSummary* CheckClassIdInstr::MakeLocationSummary(Isolate* isolate,
+                                                        bool opt) const {
+  const intptr_t kNumInputs = 2;
+  const intptr_t kNumTemps = 0;
+  LocationSummary* summary = new(isolate) LocationSummary(
+      isolate, kNumInputs, kNumTemps, LocationSummary::kNoCall);
+  summary->set_in(0, Location::RequiresRegister());
+  summary->set_in(1, Location::RegisterOrSmiConstant(right()));
+  return summary;
+}
+
+
+void CheckClassIdInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
+  Register left = locs()->in(0).reg();
+  Location right = locs()->in(1);
+  Label* deopt = compiler->AddDeoptStub(deopt_id(), ICData::kDeoptCheckClass);
+  if (right.IsRegister()) {
+    __ cmp(left, Operand(right.reg()));
+  } else {
+    ASSERT(right.IsConstant());
+    const Object& right_const = Smi::Cast(right.constant());
+    __ CompareImmediate(left, reinterpret_cast<int32_t>(right_const.raw()));
+  }
+  __ b(deopt, NE);
+}
+
+
 LocationSummary* CheckArrayBoundInstr::MakeLocationSummary(Isolate* isolate,
                                                            bool opt) const {
   const intptr_t kNumInputs = 2;
   const intptr_t kNumTemps = 0;
   LocationSummary* locs = new(isolate) LocationSummary(
       isolate, kNumInputs, kNumTemps, LocationSummary::kNoCall);
   locs->set_in(kLengthPos, Location::RegisterOrSmiConstant(length()));
   locs->set_in(kIndexPos, Location::RegisterOrSmiConstant(index()));
   return locs;
 }
@@ skipping 689 matching lines @@
   compiler->GenerateCall(token_pos(), &label, stub_kind_, locs());
 #if defined(DEBUG)
   __ LoadImmediate(R4, kInvalidObjectPointer);
   __ LoadImmediate(R5, kInvalidObjectPointer);
 #endif
 }
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_ARM