Revert "VM: Array bounds checks that don't deoptimize for precompiled code."

runtime/vm/intermediate_language_arm64.cc

Index: runtime/vm/intermediate_language_arm64.cc
diff --git a/runtime/vm/intermediate_language_arm64.cc b/runtime/vm/intermediate_language_arm64.cc
index e5431e00dd08d4fa1098f3f15f7d37bf73bc5470..642bc9ef5a39ce8050a72cf660dc8e0c504a96be 100644
--- a/runtime/vm/intermediate_language_arm64.cc
+++ b/runtime/vm/intermediate_language_arm64.cc
@@ -5254,72 +5254,8 @@ void CheckSmiInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   Label* deopt = compiler->AddDeoptStub(deopt_id(),
                                         ICData::kDeoptCheckSmi,
                                         licm_hoisted_ ? ICData::kHoisted : 0);
-  __ BranchIfNotSmi(value, deopt);
-}
-
-
-
-LocationSummary* GenericCheckBoundInstr::MakeLocationSummary(Zone* zone,
-                                                             bool opt) const {
-  const intptr_t kNumInputs = 2;
-  const intptr_t kNumTemps = 0;
-  LocationSummary* locs = new(zone) LocationSummary(
-      zone, kNumInputs, kNumTemps, LocationSummary::kCallOnSlowPath);
-  locs->set_in(kLengthPos, Location::RequiresRegister());
-  locs->set_in(kIndexPos, Location::RequiresRegister());
-  return locs;
-}
-
-
-class RangeErrorSlowPath : public SlowPathCode {
- public:
-  RangeErrorSlowPath(GenericCheckBoundInstr* instruction, intptr_t try_index)
-      : instruction_(instruction), try_index_(try_index) { }
-
-  virtual void EmitNativeCode(FlowGraphCompiler* compiler) {
-    if (Assembler::EmittingComments()) {
-      __ Comment("slow path check bound operation");
-    }
-    __ Bind(entry_label());
-    LocationSummary* locs = instruction_->locs();
-    __ Push(locs->in(0).reg());
-    __ Push(locs->in(1).reg());
-    compiler->GenerateRuntimeCall(instruction_->token_pos(),
-                                  instruction_->deopt_id(),
-                                  kRangeErrorRuntimeEntry,
-                                  2,
-                                  instruction_->locs());
-    compiler->RecordSafepoint(locs, /* slow_path_argument_count = */ 2);
-    compiler->pc_descriptors_list()->AddDescriptor(
-        RawPcDescriptors::kOther,
-        compiler->assembler()->CodeSize(),
-        instruction_->deopt_id(),
-        instruction_->token_pos(),
-        try_index_);
-    __ brk(0);
-  }
-
- private:
-  GenericCheckBoundInstr* instruction_;
-  intptr_t try_index_;
-};
-
-
-void GenericCheckBoundInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
-  RangeErrorSlowPath* slow_path =
-      new RangeErrorSlowPath(this, compiler->CurrentTryIndex());
-  compiler->AddSlowPathCode(slow_path);
-
-  Location length_loc = locs()->in(kLengthPos);
-  Location index_loc = locs()->in(kIndexPos);
-  Register length = length_loc.reg();
-  Register index = index_loc.reg();
-  const intptr_t index_cid = this->index()->Type()->ToCid();
-  if (index_cid != kSmiCid) {
-    __ BranchIfNotSmi(index, slow_path->entry_label());
-  }
-  __ cmp(index, Operand(length));
-  __ b(slow_path->entry_label(), CS);
+  __ tsti(value, Immediate(kSmiTagMask));
+  __ b(deopt, NE);
 }
 
 
@@ -5346,7 +5282,6 @@ void CheckArrayBoundInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   Location length_loc = locs()->in(kLengthPos);
   Location index_loc = locs()->in(kIndexPos);
 
-  const intptr_t index_cid = index()->Type()->ToCid();
   if (length_loc.IsConstant() && index_loc.IsConstant()) {
     // TODO(srdjan): remove this code once failures are fixed.
     if ((Smi::Cast(length_loc.constant()).Value() >
@@ -5372,9 +5307,6 @@ void CheckArrayBoundInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   } else if (length_loc.IsConstant()) {
     const Smi& length = Smi::Cast(length_loc.constant());
     const Register index = index_loc.reg();
-    if (index_cid != kSmiCid) {
-      __ BranchIfNotSmi(index, deopt);
-    }
     if (length.Value() == Smi::kMaxValue) {
       __ tst(index, Operand(index));
       __ b(deopt, MI);
@@ -5385,9 +5317,6 @@ void CheckArrayBoundInstr::EmitNativeCode(FlowGraphCompiler* compiler) {
   } else {
     const Register length = length_loc.reg();
     const Register index = index_loc.reg();
-    if (index_cid != kSmiCid) {
-      __ BranchIfNotSmi(index, deopt);
-    }
     __ CompareRegisters(index, length);
     __ b(deopt, CS);
   }