Improve our simple elimination of hole checks.

src/arm/lithium-codegen-arm.cc

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 2189 matching lines @@
   __ ldm(ia_w, sp, fp.bit() | lr.bit());
   __ add(sp, sp, Operand(sp_delta));
   __ Jump(lr);
 }
 
 
 void LCodeGen::DoLoadGlobalCell(LLoadGlobalCell* instr) {
   Register result = ToRegister(instr->result());
   __ mov(ip, Operand(Handle<Object>(instr->hydrogen()->cell())));
   __ ldr(result, FieldMemOperand(ip, JSGlobalPropertyCell::kValueOffset));
-  if (instr->hydrogen()->check_hole_value()) {
+  if (instr->hydrogen()->RequiresHoleCheck()) {
     __ LoadRoot(ip, Heap::kTheHoleValueRootIndex);
     __ cmp(result, ip);
     DeoptimizeIf(eq, instr->environment());
   }
 }
 
 
 void LCodeGen::DoLoadGlobalGeneric(LLoadGlobalGeneric* instr) {
   ASSERT(ToRegister(instr->global_object()).is(r0));
   ASSERT(ToRegister(instr->result()).is(r0));
@@ skipping 11 matching lines @@
   Register scratch = scratch0();
   Register scratch2 = ToRegister(instr->TempAt(0));
 
   // Load the cell.
   __ mov(scratch, Operand(Handle<Object>(instr->hydrogen()->cell())));
 
   // If the cell we are storing to contains the hole it could have
   // been deleted from the property dictionary. In that case, we need
   // to update the property details in the property dictionary to mark
   // it as no longer deleted.
-  if (instr->hydrogen()->check_hole_value()) {
+  if (instr->hydrogen()->RequiresHoleCheck()) {
     __ ldr(scratch2,
            FieldMemOperand(scratch, JSGlobalPropertyCell::kValueOffset));
     __ LoadRoot(ip, Heap::kTheHoleValueRootIndex);
     __ cmp(scratch2, ip);
     DeoptimizeIf(eq, instr->environment());
   }
 
   // Store the value.
   __ str(value, FieldMemOperand(scratch, JSGlobalPropertyCell::kValueOffset));
 
@@ skipping 281 matching lines @@
   Operand operand = key_is_constant
       ? Operand(constant_key * (1 << shift_size) +
                 FixedDoubleArray::kHeaderSize - kHeapObjectTag)
       : Operand(key, LSL, shift_size);
   __ add(elements, elements, operand);
   if (!key_is_constant) {
     __ add(elements, elements,
            Operand(FixedDoubleArray::kHeaderSize - kHeapObjectTag));
   }
 
-  if (instr->hydrogen()->RequiresHoleCheck()) {
-    // TODO(danno): If no hole check is required, there is no need to allocate
-    // elements into a temporary register, instead scratch can be used.
-    __ ldr(scratch, MemOperand(elements, sizeof(kHoleNanLower32)));
-    __ cmp(scratch, Operand(kHoleNanUpper32));
-    DeoptimizeIf(eq, instr->environment());
-  }
+  __ ldr(scratch, MemOperand(elements, sizeof(kHoleNanLower32)));
+  __ cmp(scratch, Operand(kHoleNanUpper32));
+  DeoptimizeIf(eq, instr->environment());
 
   __ vldr(result, elements, 0);
 }
 
 
 void LCodeGen::DoLoadKeyedSpecializedArrayElement(
     LLoadKeyedSpecializedArrayElement* instr) {
   Register external_pointer = ToRegister(instr->external_pointer());
   Register key = no_reg;
   ElementsKind elements_kind = instr->elements_kind();
@@ skipping 2009 matching lines @@
   ASSERT(osr_pc_offset_ == -1);
   osr_pc_offset_ = masm()->pc_offset();
 }
 
 
 
 
 #undef __
 
 } }  // namespace v8::internal