Replace DeoptimizeOnUndefined with whitelisting AllowUndefinedAsNan

R=danno@chromium.org

Review URL: https://chromiumcodereview.appspot.com/15952007

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@14894 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/arm/lithium-codegen-arm.cc

@@ -4976,7 +4976,7 @@ void LCodeGen::DoSmiUntag(LSmiUntag* instr) {
 
 void LCodeGen::EmitNumberUntagD(Register input_reg,
                                 DwVfpRegister result_reg,
-                                bool deoptimize_on_undefined,
+                                bool allow_undefined_as_nan,
                                 bool deoptimize_on_minus_zero,
                                 LEnvironment* env,
                                 NumberUntagDMode mode) {
@@ -4996,7 +4996,7 @@ void LCodeGen::EmitNumberUntagD(Register input_reg,
     __ ldr(scratch, FieldMemOperand(input_reg, HeapObject::kMapOffset));
     __ LoadRoot(ip, Heap::kHeapNumberMapRootIndex);
     __ cmp(scratch, Operand(ip));
-    if (deoptimize_on_undefined) {
+    if (!allow_undefined_as_nan) {
       DeoptimizeIf(ne, env);
     } else {
       Label heap_number, convert;
@@ -5166,7 +5166,7 @@ void LCodeGen::DoNumberUntagD(LNumberUntagD* instr) {
   }
 
   EmitNumberUntagD(input_reg, result_reg,
-                   instr->hydrogen()->deoptimize_on_undefined(),
+                   instr->hydrogen()->allow_undefined_as_nan(),
                    instr->hydrogen()->deoptimize_on_minus_zero(),
                    instr->environment(),
                    mode);

src/arm/lithium-codegen-arm.h

@@ -335,7 +335,7 @@ class LCodeGen BASE_EMBEDDED {
   void EmitBranch(int left_block, int right_block, Condition cc);
   void EmitNumberUntagD(Register input,
                         DwVfpRegister result,
-                        bool deoptimize_on_undefined,
+                        bool allow_undefined_as_nan,
                         bool deoptimize_on_minus_zero,
                         LEnvironment* env,
                         NumberUntagDMode mode);

src/hydrogen-instructions.cc

@@ -1485,7 +1485,7 @@ void HChange::PrintDataTo(StringStream* stream) {
 
   if (CanTruncateToInt32()) stream->Add(" truncating-int32");
   if (CheckFlag(kBailoutOnMinusZero)) stream->Add(" -0?");
-  if (CheckFlag(kDeoptimizeOnUndefined)) stream->Add(" deopt-on-undefined");
+  if (CheckFlag(kAllowUndefinedAsNaN)) stream->Add(" allow-undefined-as-nan");
 }
 
 
@@ -2490,8 +2490,8 @@ void HCompareIDAndBranch::InferRepresentation(HInferRepresentation* h_infer) {
     // (false). Therefore, any comparisons other than ordered relational
     // comparisons must cause a deopt when one of their arguments is undefined.
     // See also v8:1434
-    if (!Token::IsOrderedRelationalCompareOp(token_)) {
-      SetFlag(kDeoptimizeOnUndefined);
+    if (Token::IsOrderedRelationalCompareOp(token_)) {
+      SetFlag(kAllowUndefinedAsNaN);
     }
   }
   ChangeRepresentation(rep);
@@ -2754,7 +2754,7 @@ bool HLoadKeyed::AllUsesCanTreatHoleAsNaN() const {
 
   for (HUseIterator it(uses()); !it.Done(); it.Advance()) {
     HValue* use = it.value();
-    if (use->CheckFlag(HValue::kDeoptimizeOnUndefined)) {
+    if (!use->CheckFlag(HValue::kAllowUndefinedAsNaN)) {
       return false;
     }
   }
@@ -3749,7 +3749,6 @@ void HObjectAccess::SetGVNFlags(HValue *instr, bool is_store) {
     // track dominating allocations in order to eliminate write barriers
     instr->SetGVNFlag(kDependsOnNewSpacePromotion);
     instr->SetFlag(HValue::kTrackSideEffectDominators);
-    instr->SetFlag(HValue::kDeoptimizeOnUndefined);
   } else {
     // try to GVN loads, but don't hoist above map changes
     instr->SetFlag(HValue::kUseGVN);

src/hydrogen-instructions.h

@@ -790,7 +790,7 @@ class HValue: public ZoneObject {
     kCanOverflow,
     kBailoutOnMinusZero,
     kCanBeDivByZero,
-    kDeoptimizeOnUndefined,
+    kAllowUndefinedAsNaN,
     kIsArguments,
     kTruncatingToInt32,
     // Set after an instruction is killed.
@@ -1715,14 +1715,14 @@ class HChange: public HUnaryOperation {
   HChange(HValue* value,
           Representation to,
           bool is_truncating,
-          bool deoptimize_on_undefined)
+          bool allow_undefined_as_nan)
       : HUnaryOperation(value) {
     ASSERT(!value->representation().IsNone());
     ASSERT(!to.IsNone());
     ASSERT(!value->representation().Equals(to));
     set_representation(to);
     SetFlag(kUseGVN);
-    if (deoptimize_on_undefined) SetFlag(kDeoptimizeOnUndefined);
+    if (allow_undefined_as_nan) SetFlag(kAllowUndefinedAsNaN);
     if (is_truncating) SetFlag(kTruncatingToInt32);
     if (value->representation().IsSmi() || value->type().IsSmi()) {
       set_type(HType::Smi());
@@ -1738,8 +1738,8 @@ class HChange: public HUnaryOperation {
 
   Representation from() const { return value()->representation(); }
   Representation to() const { return representation(); }
-  bool deoptimize_on_undefined() const {
-    return CheckFlag(kDeoptimizeOnUndefined);
+  bool allow_undefined_as_nan() const {
+    return CheckFlag(kAllowUndefinedAsNaN);
   }
   bool deoptimize_on_minus_zero() const {
     return CheckFlag(kBailoutOnMinusZero);
@@ -1769,6 +1769,7 @@ class HClampToUint8: public HUnaryOperation {
   explicit HClampToUint8(HValue* value)
       : HUnaryOperation(value) {
     set_representation(Representation::Integer32());
+    SetFlag(kAllowUndefinedAsNaN);
     SetFlag(kUseGVN);
   }
 
@@ -2495,6 +2496,7 @@ class HBitNot: public HUnaryOperation {
     set_representation(Representation::Integer32());
     SetFlag(kUseGVN);
     SetFlag(kTruncatingToInt32);
+    SetFlag(kAllowUndefinedAsNaN);
   }
 
   virtual Representation RequiredInputRepresentation(int index) {
@@ -2604,6 +2606,7 @@ class HUnaryMathOperation: public HTemplateInstruction<2> {
         UNREACHABLE();
     }
     SetFlag(kUseGVN);
+    SetFlag(kAllowUndefinedAsNaN);
   }
 
   virtual bool IsDeletable() const { return true; }
@@ -2945,6 +2948,7 @@ class HPhi: public HValue {
     }
     ASSERT(merged_index >= 0);
     SetFlag(kFlexibleRepresentation);
+    SetFlag(kAllowUndefinedAsNaN);
   }
 
   virtual Representation RepresentationFromInputs();
@@ -3668,6 +3672,7 @@ class HBitwiseBinaryOperation: public HBinaryOperation {
       : HBinaryOperation(context, left, right) {
     SetFlag(kFlexibleRepresentation);
     SetFlag(kTruncatingToInt32);
+    SetFlag(kAllowUndefinedAsNaN);
     SetAllSideEffects();
   }
 
@@ -3722,6 +3727,7 @@ class HMathFloorOfDiv: public HBinaryOperation {
     if (!right->IsConstant()) {
       SetFlag(kCanBeDivByZero);
     }
+    SetFlag(kAllowUndefinedAsNaN);
   }
 
   virtual HValue* EnsureAndPropagateNotMinusZero(BitVector* visited);
@@ -3746,6 +3752,7 @@ class HArithmeticBinaryOperation: public HBinaryOperation {
       : HBinaryOperation(context, left, right) {
     SetAllSideEffects();
     SetFlag(kFlexibleRepresentation);
+    SetFlag(kAllowUndefinedAsNaN);
   }
 
   virtual void RepresentationChanged(Representation to) {
@@ -5731,12 +5738,11 @@ class HStoreKeyed
     }
     if (is_external()) {
       SetGVNFlag(kChangesSpecializedArrayElements);
+      SetFlag(kAllowUndefinedAsNaN);
     } else if (IsFastDoubleElementsKind(elements_kind)) {
       SetGVNFlag(kChangesDoubleArrayElements);
-      SetFlag(kDeoptimizeOnUndefined);
     } else if (IsFastSmiElementsKind(elements_kind)) {
       SetGVNFlag(kChangesArrayElements);
-      SetFlag(kDeoptimizeOnUndefined);
     } else {
       SetGVNFlag(kChangesArrayElements);
     }

src/hydrogen.cc

@@ -1586,7 +1586,10 @@ void HGraphBuilder::BuildCopyElements(HValue* context,
       ? FAST_HOLEY_ELEMENTS : to_elements_kind;
   HInstruction* holey_store = AddInstruction(
       new(zone()) HStoreKeyed(to_elements, key, element, holey_kind));
-  holey_store->ClearFlag(HValue::kDeoptimizeOnUndefined);
+  // Allow NaN hole values to converted to their tagged counterparts.
+  if (IsFastHoleyElementsKind(to_elements_kind)) {
+    holey_store->SetFlag(HValue::kAllowUndefinedAsNaN);
+  }
 
   builder.EndBody();
 
@@ -3100,8 +3103,8 @@ void HGraph::InsertRepresentationChangeForUse(HValue* value,
   // change instructions for them.
   HInstruction* new_value = NULL;
   bool is_truncating = use_value->CheckFlag(HValue::kTruncatingToInt32);
-  bool deoptimize_on_undefined =
-      use_value->CheckFlag(HValue::kDeoptimizeOnUndefined);
+  bool allow_undefined_as_nan =
+      use_value->CheckFlag(HValue::kAllowUndefinedAsNaN);
   if (value->IsConstant()) {
     HConstant* constant = HConstant::cast(value);
     // Try to create a new copy of the constant with the new representation.
@@ -3112,7 +3115,7 @@ void HGraph::InsertRepresentationChangeForUse(HValue* value,
 
   if (new_value == NULL) {
     new_value = new(zone()) HChange(value, to,
-                                    is_truncating, deoptimize_on_undefined);
+                                    is_truncating, allow_undefined_as_nan);
   }
 
   new_value->InsertBefore(next);
@@ -3219,8 +3222,8 @@ void HGraph::InsertRepresentationChanges() {
 
 
 void HGraph::RecursivelyMarkPhiDeoptimizeOnUndefined(HPhi* phi) {
-  if (phi->CheckFlag(HValue::kDeoptimizeOnUndefined)) return;
-  phi->SetFlag(HValue::kDeoptimizeOnUndefined);
+  if (!phi->CheckFlag(HValue::kAllowUndefinedAsNaN)) return;
+  phi->ClearFlag(HValue::kAllowUndefinedAsNaN);
   for (int i = 0; i < phi->OperandCount(); ++i) {
     HValue* input = phi->OperandAt(i);
     if (input->IsPhi()) {
@@ -3240,16 +3243,11 @@ void HGraph::MarkDeoptimizeOnUndefined() {
   // if one of its uses has this flag set.
   for (int i = 0; i < phi_list()->length(); i++) {
     HPhi* phi = phi_list()->at(i);
-    if (phi->representation().IsDouble()) {
-      for (HUseIterator it(phi->uses()); !it.Done(); it.Advance()) {
-        int use_index = it.index();
-        HValue* use_value = it.value();
-        Representation req = use_value->RequiredInputRepresentation(use_index);
-        if (!req.IsDouble() ||
-            use_value->CheckFlag(HValue::kDeoptimizeOnUndefined)) {
-          RecursivelyMarkPhiDeoptimizeOnUndefined(phi);
-          break;
-        }
+    for (HUseIterator it(phi->uses()); !it.Done(); it.Advance()) {
+      HValue* use_value = it.value();
+      if (!use_value->CheckFlag(HValue::kAllowUndefinedAsNaN)) {
+        RecursivelyMarkPhiDeoptimizeOnUndefined(phi);
+        break;
       }
     }
   }
@@ -10109,7 +10107,7 @@ void HOptimizedGraphBuilder::BuildEmitFixedDoubleArray(
             boilerplate_elements, key_constant, NULL, kind, ALLOW_RETURN_HOLE));
     HInstruction* store = AddInstruction(new(zone) HStoreKeyed(
         object_elements, key_constant, value_instruction, kind));
-    store->ClearFlag(HValue::kDeoptimizeOnUndefined);
+    store->SetFlag(HValue::kAllowUndefinedAsNaN);
   }
 }
 

src/ia32/lithium-codegen-ia32.cc

@@ -5095,7 +5095,7 @@ void LCodeGen::DoSmiUntag(LSmiUntag* instr) {
 
 void LCodeGen::EmitNumberUntagDNoSSE2(Register input_reg,
                                       Register temp_reg,
-                                      bool deoptimize_on_undefined,
+                                      bool allow_undefined_as_nan,
                                       bool deoptimize_on_minus_zero,
                                       LEnvironment* env,
                                       NumberUntagDMode mode) {
@@ -5110,7 +5110,7 @@ void LCodeGen::EmitNumberUntagDNoSSE2(Register input_reg,
     // Heap number map check.
     __ cmp(FieldOperand(input_reg, HeapObject::kMapOffset),
            factory()->heap_number_map());
-    if (deoptimize_on_undefined) {
+    if (!allow_undefined_as_nan) {
       DeoptimizeIf(not_equal, env);
     } else {
       Label heap_number, convert;
@@ -5167,7 +5167,7 @@ void LCodeGen::EmitNumberUntagDNoSSE2(Register input_reg,
 void LCodeGen::EmitNumberUntagD(Register input_reg,
                                 Register temp_reg,
                                 XMMRegister result_reg,
-                                bool deoptimize_on_undefined,
+                                bool allow_undefined_as_nan,
                                 bool deoptimize_on_minus_zero,
                                 LEnvironment* env,
                                 NumberUntagDMode mode) {
@@ -5182,7 +5182,7 @@ void LCodeGen::EmitNumberUntagD(Register input_reg,
     // Heap number map check.
     __ cmp(FieldOperand(input_reg, HeapObject::kMapOffset),
            factory()->heap_number_map());
-    if (deoptimize_on_undefined) {
+    if (!allow_undefined_as_nan) {
       DeoptimizeIf(not_equal, env);
     } else {
       Label heap_number, convert;
@@ -5530,14 +5530,14 @@ void LCodeGen::DoNumberUntagD(LNumberUntagD* instr) {
     EmitNumberUntagD(input_reg,
                      temp_reg,
                      result_reg,
-                     instr->hydrogen()->deoptimize_on_undefined(),
+                     instr->hydrogen()->allow_undefined_as_nan(),
                      deoptimize_on_minus_zero,
                      instr->environment(),
                      mode);
   } else {
     EmitNumberUntagDNoSSE2(input_reg,
                            temp_reg,
-                           instr->hydrogen()->deoptimize_on_undefined(),
+                           instr->hydrogen()->allow_undefined_as_nan(),
                            deoptimize_on_minus_zero,
                            instr->environment(),
                            mode);

src/ia32/lithium-codegen-ia32.h

@@ -331,7 +331,7 @@ class LCodeGen BASE_EMBEDDED {
       Register input,
       Register temp,
       XMMRegister result,
-      bool deoptimize_on_undefined,
+      bool allow_undefined_as_nan,
       bool deoptimize_on_minus_zero,
       LEnvironment* env,
       NumberUntagDMode mode = NUMBER_CANDIDATE_IS_ANY_TAGGED);
@@ -339,7 +339,7 @@ class LCodeGen BASE_EMBEDDED {
   void EmitNumberUntagDNoSSE2(
       Register input,
       Register temp,
-      bool deoptimize_on_undefined,
+      bool allow_undefined_as_nan,
       bool deoptimize_on_minus_zero,
       LEnvironment* env,
       NumberUntagDMode mode = NUMBER_CANDIDATE_IS_ANY_TAGGED);

src/x64/lithium-codegen-x64.cc

@@ -4688,7 +4688,7 @@ void LCodeGen::DoSmiUntag(LSmiUntag* instr) {
 
 void LCodeGen::EmitNumberUntagD(Register input_reg,
                                 XMMRegister result_reg,
-                                bool deoptimize_on_undefined,
+                                bool allow_undefined_as_nan,
                                 bool deoptimize_on_minus_zero,
                                 LEnvironment* env,
                                 NumberUntagDMode mode) {
@@ -4703,7 +4703,7 @@ void LCodeGen::EmitNumberUntagD(Register input_reg,
     // Heap number map check.
     __ CompareRoot(FieldOperand(input_reg, HeapObject::kMapOffset),
                    Heap::kHeapNumberMapRootIndex);
-    if (deoptimize_on_undefined) {
+    if (!allow_undefined_as_nan) {
       DeoptimizeIf(not_equal, env);
     } else {
       Label heap_number, convert;
@@ -4839,7 +4839,7 @@ void LCodeGen::DoNumberUntagD(LNumberUntagD* instr) {
   }
 
   EmitNumberUntagD(input_reg, result_reg,
-                   instr->hydrogen()->deoptimize_on_undefined(),
+                   instr->hydrogen()->allow_undefined_as_nan(),
                    instr->hydrogen()->deoptimize_on_minus_zero(),
                    instr->environment(),
                    mode);

src/x64/lithium-codegen-x64.h

@@ -295,7 +295,7 @@ class LCodeGen BASE_EMBEDDED {
   void EmitNumberUntagD(
       Register input,
       XMMRegister result,
-      bool deoptimize_on_undefined,
+      bool allow_undefined_as_nan,
       bool deoptimize_on_minus_zero,
       LEnvironment* env,
       NumberUntagDMode mode = NUMBER_CANDIDATE_IS_ANY_TAGGED);

test/mjsunit/regress/regress-convert-hole.js

@@ -27,7 +27,7 @@
 
 // Flags: --allow-natives-syntax
 
-function f(test, test2, a, i) {
+function f_store(test, test2, a, i) {
   var o = [0.5,1,,3];
   var d;
   if (test) {
@@ -42,11 +42,67 @@ function f(test, test2, a, i) {
   return d;
 }
 
-var a = [0, 0, 0, {}];
-f(true, false, a, 0);
-f(true, true, a, 0);
-f(false, false, a, 1);
-f(false, true, a, 1);
-%OptimizeFunctionOnNextCall(f);
-f(false, false, a, 2);
-assertEquals(undefined, a[2]);
+var a1 = [0, 0, 0, {}];
+f_store(true, false, a1, 0);
+f_store(true, true, a1, 0);
+f_store(false, false, a1, 1);
+f_store(false, true, a1, 1);
+%OptimizeFunctionOnNextCall(f_store);
+f_store(false, false, a1, 2);
+assertEquals(undefined, a1[2]);
+
+function test_arg(expected) {
+  return function(v) {
+    assertEquals(expected, v);
+  }
+}
+
+function f_call(f, test, test2, i) {
+  var o = [0.5,1,,3];
+  var d;
+  if (test) {
+    d = 1.5;
+  } else {
+    d = o[i];
+  }
+  if (test2) {
+    d += 1;
+  }
+  f(d);
+  return d;
+}
+
+f_call(test_arg(1.5), true, false, 0);
+f_call(test_arg(2.5), true, true, 0);
+f_call(test_arg(1), false, false, 1);
+f_call(test_arg(2), false, true, 1);
+%OptimizeFunctionOnNextCall(f_call);
+f_call(test_arg(undefined), false, false, 2);
+
+
+function f_external(test, test2, test3, a, i) {
+  var o = [0.5,1,,3];
+  var d;
+  if (test) {
+    d = 1.5;
+  } else {
+    d = o[i];
+  }
+  if (test2) {
+    d += 1;
+  }
+  if (test3) {
+    d = d|0;
+  }
+  a[d] = 1;
+  return d;
+}
+
+var a2 = new Int32Array(10);
+f_external(true, false, true, a2, 0);
+f_external(true, true, true, a2, 0);
+f_external(false, false, true, a2, 1);
+f_external(false, true, true, a2, 1);
+%OptimizeFunctionOnNextCall(f_external);
+f_external(false, false, false, a2, 2);
+assertEquals(1, a2[undefined]);