Revert of [strong] Implement strong mode restrictions on property access

src/ic/arm64/ic-arm64.cc

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/v8.h"
 
 #if V8_TARGET_ARCH_ARM64
 
 #include "src/codegen.h"
 #include "src/ic/ic.h"
@@ skipping 149 matching lines @@
 //
 // elements - holds the elements of the receiver and its prototypes. Clobbered.
 //
 // result   - holds the result on exit if the load succeeded.
 //            Allowed to be the the same as 'receiver' or 'key'.
 //            Unchanged on bailout so 'receiver' and 'key' can be safely
 //            used by further computation.
 static void GenerateFastArrayLoad(MacroAssembler* masm, Register receiver,
                                   Register key, Register elements,
                                   Register scratch1, Register scratch2,
-                                  Register result, Label* slow,
-                                  LanguageMode language_mode) {
+                                  Register result, Label* slow) {
   DCHECK(!AreAliased(receiver, key, elements, scratch1, scratch2));
 
   Label check_prototypes, check_next_prototype;
-  Label done, in_bounds, absent;
+  Label done, in_bounds, return_undefined;
 
   // Check for fast array.
   __ Ldr(elements, FieldMemOperand(receiver, JSObject::kElementsOffset));
   __ AssertFastElements(elements);
 
   // Check that the key (index) is within bounds.
   __ Ldr(scratch1, FieldMemOperand(elements, FixedArray::kLengthOffset));
   __ Cmp(key, scratch1);
   __ B(lo, &in_bounds);
 
   // Out of bounds. Check the prototype chain to see if we can just return
   // 'undefined'.
   __ Cmp(key, Operand(Smi::FromInt(0)));
   __ B(lt, slow);  // Negative keys can't take the fast OOB path.
   __ Bind(&check_prototypes);
   __ Ldr(scratch2, FieldMemOperand(receiver, HeapObject::kMapOffset));
   __ Bind(&check_next_prototype);
   __ Ldr(scratch2, FieldMemOperand(scratch2, Map::kPrototypeOffset));
   // scratch2: current prototype
-  __ JumpIfRoot(scratch2, Heap::kNullValueRootIndex, &absent);
+  __ JumpIfRoot(scratch2, Heap::kNullValueRootIndex, &return_undefined);
   __ Ldr(elements, FieldMemOperand(scratch2, JSObject::kElementsOffset));
   __ Ldr(scratch2, FieldMemOperand(scratch2, HeapObject::kMapOffset));
   // elements: elements of current prototype
   // scratch2: map of current prototype
   __ CompareInstanceType(scratch2, scratch1, JS_OBJECT_TYPE);
   __ B(lo, slow);
   __ Ldrb(scratch1, FieldMemOperand(scratch2, Map::kBitFieldOffset));
   __ Tbnz(scratch1, Map::kIsAccessCheckNeeded, slow);
   __ Tbnz(scratch1, Map::kHasIndexedInterceptor, slow);
   __ JumpIfNotRoot(elements, Heap::kEmptyFixedArrayRootIndex, slow);
   __ B(&check_next_prototype);
 
-  __ Bind(&absent);
-  if (is_strong(language_mode)) {
-    // Strong mode accesses must throw in this case, so call the runtime.
-    __ B(slow);
-  } else {
-    __ LoadRoot(result, Heap::kUndefinedValueRootIndex);
-    __ B(&done);
-  }
+  __ Bind(&return_undefined);
+  __ LoadRoot(result, Heap::kUndefinedValueRootIndex);
+  __ B(&done);
 
   __ Bind(&in_bounds);
   // Fast case: Do the load.
   __ Add(scratch1, elements, FixedArray::kHeaderSize - kHeapObjectTag);
   __ SmiUntag(scratch2, key);
   __ Ldr(scratch2, MemOperand(scratch1, scratch2, LSL, kPointerSizeLog2));
 
   // In case the loaded value is the_hole we have to check the prototype chain.
   __ JumpIfRoot(scratch2, Heap::kTheHoleValueRootIndex, &check_prototypes);
 
@@ skipping 45 matching lines @@
   Label slow;
 
   __ Ldr(dictionary, FieldMemOperand(LoadDescriptor::ReceiverRegister(),
                                      JSObject::kPropertiesOffset));
   GenerateDictionaryLoad(masm, &slow, dictionary,
                          LoadDescriptor::NameRegister(), x0, x3, x4);
   __ Ret();
 
   // Dictionary load failed, go slow (but don't miss).
   __ Bind(&slow);
-  GenerateSlow(masm);
+  GenerateRuntimeGetProperty(masm);
 }
 
 
 void LoadIC::GenerateMiss(MacroAssembler* masm) {
   // The return address is in lr.
   Isolate* isolate = masm->isolate();
   ASM_LOCATION("LoadIC::GenerateMiss");
 
   DCHECK(!AreAliased(x4, x5, LoadWithVectorDescriptor::SlotRegister(),
                      LoadWithVectorDescriptor::VectorRegister()));
   __ IncrementCounter(isolate->counters()->load_miss(), 1, x4, x5);
 
   // Perform tail call to the entry.
   __ Push(LoadWithVectorDescriptor::ReceiverRegister(),
           LoadWithVectorDescriptor::NameRegister(),
           LoadWithVectorDescriptor::SlotRegister(),
           LoadWithVectorDescriptor::VectorRegister());
   ExternalReference ref = ExternalReference(IC_Utility(kLoadIC_Miss), isolate);
   int arg_count = 4;
   __ TailCallExternalReference(ref, arg_count, 1);
 }
 
 
-void LoadIC::GenerateSlow(MacroAssembler* masm) {
+void LoadIC::GenerateRuntimeGetProperty(MacroAssembler* masm) {
   // The return address is in lr.
   __ Push(LoadDescriptor::ReceiverRegister(), LoadDescriptor::NameRegister());
-
-  // Perform tail call to the entry.
-  ExternalReference ref =
-      ExternalReference(IC_Utility(kLoadIC_Slow), masm->isolate());
-  int arg_count = 2;
-  __ TailCallExternalReference(ref, arg_count, 1);
+  __ TailCallRuntime(Runtime::kGetProperty, 2, 1);
 }
 
 
 void KeyedLoadIC::GenerateMiss(MacroAssembler* masm) {
   // The return address is in lr.
   Isolate* isolate = masm->isolate();
 
   DCHECK(!AreAliased(x10, x11, LoadWithVectorDescriptor::SlotRegister(),
                      LoadWithVectorDescriptor::VectorRegister()));
   __ IncrementCounter(isolate->counters()->keyed_load_miss(), 1, x10, x11);
 
   __ Push(LoadWithVectorDescriptor::ReceiverRegister(),
           LoadWithVectorDescriptor::NameRegister(),
           LoadWithVectorDescriptor::SlotRegister(),
           LoadWithVectorDescriptor::VectorRegister());
 
   // Perform tail call to the entry.
   ExternalReference ref =
       ExternalReference(IC_Utility(kKeyedLoadIC_Miss), isolate);
   int arg_count = 4;
   __ TailCallExternalReference(ref, arg_count, 1);
 }
 
 
-void KeyedLoadIC::GenerateSlow(MacroAssembler* masm) {
+void KeyedLoadIC::GenerateRuntimeGetProperty(MacroAssembler* masm) {
   // The return address is in lr.
   __ Push(LoadDescriptor::ReceiverRegister(), LoadDescriptor::NameRegister());
-
-  // Perform tail call to the entry.
-  ExternalReference ref =
-      ExternalReference(IC_Utility(kKeyedLoadIC_Slow), masm->isolate());
-  int arg_count = 2;
-  __ TailCallExternalReference(ref, arg_count, 1);
+  __ TailCallRuntime(Runtime::kKeyedGetProperty, 2, 1);
 }
 
 
 static void GenerateKeyedLoadWithSmiKey(MacroAssembler* masm, Register key,
                                         Register receiver, Register scratch1,
                                         Register scratch2, Register scratch3,
                                         Register scratch4, Register scratch5,
-                                        Label* slow,
-                                        LanguageMode language_mode) {
+                                        Label* slow) {
   DCHECK(!AreAliased(key, receiver, scratch1, scratch2, scratch3, scratch4,
                      scratch5));
 
   Isolate* isolate = masm->isolate();
   Label check_number_dictionary;
   // If we can load the value, it should be returned in x0.
   Register result = x0;
 
   GenerateKeyedLoadReceiverCheck(masm, receiver, scratch1, scratch2,
                                  Map::kHasIndexedInterceptor, slow);
 
   // Check the receiver's map to see if it has fast elements.
   __ CheckFastElements(scratch1, scratch2, &check_number_dictionary);
 
   GenerateFastArrayLoad(masm, receiver, key, scratch3, scratch2, scratch1,
-                        result, slow, language_mode);
+                        result, slow);
   __ IncrementCounter(isolate->counters()->keyed_load_generic_smi(), 1,
                       scratch1, scratch2);
   __ Ret();
 
   __ Bind(&check_number_dictionary);
   __ Ldr(scratch3, FieldMemOperand(receiver, JSObject::kElementsOffset));
   __ Ldr(scratch2, FieldMemOperand(scratch3, JSObject::kMapOffset));
 
   // Check whether we have a number dictionary.
   __ JumpIfNotRoot(scratch2, Heap::kHashTableMapRootIndex, slow);
@@ skipping 50 matching lines @@
   __ Ldrb(scratch1, FieldMemOperand(scratch1, Map::kInstanceTypeOffset));
   GenerateGlobalInstanceTypeCheck(masm, scratch1, slow);
   // Load the property.
   GenerateDictionaryLoad(masm, slow, scratch2, key, result, scratch1, scratch3);
   __ IncrementCounter(isolate->counters()->keyed_load_generic_symbol(), 1,
                       scratch1, scratch2);
   __ Ret();
 }
 
 
-void KeyedLoadIC::GenerateMegamorphic(MacroAssembler* masm,
-                                      LanguageMode language_mode) {
+void KeyedLoadIC::GenerateMegamorphic(MacroAssembler* masm) {
   // The return address is in lr.
   Label slow, check_name, index_smi, index_name;
 
   Register key = LoadDescriptor::NameRegister();
   Register receiver = LoadDescriptor::ReceiverRegister();
   DCHECK(key.is(x2));
   DCHECK(receiver.is(x1));
 
   __ JumpIfNotSmi(key, &check_name);
   __ Bind(&index_smi);
   // Now the key is known to be a smi. This place is also jumped to from below
   // where a numeric string is converted to a smi.
-  GenerateKeyedLoadWithSmiKey(masm, key, receiver, x7, x3, x4, x5, x6, &slow,
-                              language_mode);
+  GenerateKeyedLoadWithSmiKey(masm, key, receiver, x7, x3, x4, x5, x6, &slow);
 
   // Slow case.
   __ Bind(&slow);
   __ IncrementCounter(masm->isolate()->counters()->keyed_load_generic_slow(), 1,
                       x4, x3);
-  GenerateSlow(masm);
+  GenerateRuntimeGetProperty(masm);
 
   __ Bind(&check_name);
   GenerateKeyNameCheck(masm, key, x0, x3, &index_name, &slow);
 
   GenerateKeyedLoadWithNameKey(masm, key, receiver, x4, x5, x6, x7, x3, &slow);
 
   __ Bind(&index_name);
   __ IndexFromHash(x3, key);
   // Now jump to the place where smi keys are handled.
   __ B(&index_smi);
@@ skipping 393 matching lines @@
   } else {
     DCHECK(to_patch->Mask(TestBranchMask) == TBNZ);
     // This is JumpIfSmi(smi_reg, branch_imm).
     patcher.tbz(smi_reg, 0, branch_imm);
   }
 }
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_ARM64