Generalize bounds checks.

runtime/vm/intermediate_language_arm64.cc

 // Copyright (c) 2014, 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_ARM64.
 #if defined(TARGET_ARCH_ARM64)
 
 #include "vm/intermediate_language.h"
 
 #include "vm/dart_entry.h"
@@ skipping 4888 matching lines @@
     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;
+  Label* deopt = compiler->AddDeoptStub(deopt_id(),
+                                        ICData::kDeoptCheckClass,
+                                        licm_hoisted_ ? ICData::kHoisted : 0);
   if (IsNullCheck()) {
-    Label* deopt = compiler->AddDeoptStub(deopt_id(), deopt_reason);
     __ CompareObject(locs()->in(0).reg(), Object::null_object(), PP);
     __ b(deopt, EQ);
     return;
   }
 
   ASSERT((unary_checks().GetReceiverClassIdAt(0) != kSmiCid) ||
          (unary_checks().NumberOfChecks() > 1));
   const Register value = locs()->in(0).reg();
   const Register temp = locs()->temp(0).reg();
-  Label* deopt = compiler->AddDeoptStub(deopt_id(), deopt_reason);
   Label is_ok;
   intptr_t cix = 0;
   if (unary_checks().GetReceiverClassIdAt(cix) == kSmiCid) {
     __ tsti(value, kSmiTagMask);
     __ b(&is_ok, EQ);
     cix++;  // Skip first check.
   } else {
     __ tsti(value, kSmiTagMask);
     __ b(deopt, EQ);
   }
@@ skipping 76 matching lines @@
   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;
 }
 
 
 void CheckArrayBoundInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
-  Label* deopt = compiler->AddDeoptStub(deopt_id(),
-                                        ICData::kDeoptCheckArrayBound);
+  Label* deopt = compiler->AddDeoptStub(
+      deopt_id(),
+      ICData::kDeoptCheckArrayBound,
+      generalized_ ? ICData::kGeneralized : 0);
 
   Location length_loc = locs()->in(kLengthPos);
   Location index_loc = locs()->in(kIndexPos);
 
   if (length_loc.IsConstant() && index_loc.IsConstant()) {
     // TODO(srdjan): remove this code once failures are fixed.
     if ((Smi::Cast(length_loc.constant()).Value() >
          Smi::Cast(index_loc.constant()).Value()) &&
         (Smi::Cast(index_loc.constant()).Value() >= 0)) {
       // This CheckArrayBoundInstr should have been eliminated.
       return;
     }
     ASSERT((Smi::Cast(length_loc.constant()).Value() <=
             Smi::Cast(index_loc.constant()).Value()) ||
            (Smi::Cast(index_loc.constant()).Value() < 0));
     // Unconditionally deoptimize for constant bounds checks because they
     // only occur only when index is out-of-bounds.
     __ b(deopt);
     return;
   }
 
   if (index_loc.IsConstant()) {
     const Register length = length_loc.reg();
     const Smi& index = Smi::Cast(index_loc.constant());
     __ CompareImmediate(length, reinterpret_cast<int64_t>(index.raw()), PP);
     __ b(deopt, LS);
   } else if (length_loc.IsConstant()) {
     const Smi& length = Smi::Cast(length_loc.constant());
     const Register index = index_loc.reg();
-    __ CompareImmediate(index, reinterpret_cast<int64_t>(length.raw()), PP);
-    __ b(deopt, CS);
+    if (length.Value() == Smi::kMaxValue) {
+      __ tst(index, Operand(index));
+      __ b(deopt, MI);
+    } else {
+      __ CompareImmediate(index, reinterpret_cast<int64_t>(length.raw()), PP);
+      __ b(deopt, CS);
+    }
   } else {
     const Register length = length_loc.reg();
     const Register index = index_loc.reg();
     __ CompareRegisters(index, length);
     __ b(deopt, CS);
   }
 }
 
 
 LocationSummary* UnboxIntegerInstr::MakeLocationSummary(Isolate* isolate,
@@ skipping 419 matching lines @@
   compiler->GenerateCall(token_pos(), &label, stub_kind_, locs());
 #if defined(DEBUG)
   __ LoadImmediate(R4, kInvalidObjectPointer, kNoPP);
   __ LoadImmediate(R5, kInvalidObjectPointer, kNoPP);
 #endif
 }
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_ARM64