Implement tracking and optimizations of packed arrays

src/mips/lithium-codegen-mips.cc

 // Copyright 2012 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 2430 matching lines @@
     Label done, fail;
     __ lw(scratch, FieldMemOperand(result, HeapObject::kMapOffset));
     __ LoadRoot(at, Heap::kFixedArrayMapRootIndex);
     __ Branch(USE_DELAY_SLOT, &done, eq, scratch, Operand(at));
     __ LoadRoot(at, Heap::kFixedCOWArrayMapRootIndex);  // In the delay slot.
     __ Branch(&done, eq, scratch, Operand(at));
     // |scratch| still contains |input|'s map.
     __ lbu(scratch, FieldMemOperand(scratch, Map::kBitField2Offset));
     __ Ext(scratch, scratch, Map::kElementsKindShift,
            Map::kElementsKindBitCount);
-    __ Branch(&done, eq, scratch,
-              Operand(FAST_ELEMENTS));
+    __ Branch(&fail, lt, scratch,
+              Operand(GetInitialFastElementsKind()));
+    __ Branch(&done, le, scratch,
+              Operand(TERMINAL_FAST_ELEMENTS_KIND));
     __ Branch(&fail, lt, scratch,
               Operand(FIRST_EXTERNAL_ARRAY_ELEMENTS_KIND));
     __ Branch(&done, le, scratch,
               Operand(LAST_EXTERNAL_ARRAY_ELEMENTS_KIND));
     __ bind(&fail);
     __ Abort("Check for fast or external elements failed.");
     __ bind(&done);
   }
 }
 
@@ skipping 72 matching lines @@
   if (key_is_constant) {
     __ Addu(elements, elements, Operand(constant_key * (1 << shift_size) +
             FixedDoubleArray::kHeaderSize - kHeapObjectTag));
   } else {
     __ sll(scratch, key, shift_size);
     __ Addu(elements, elements, Operand(scratch));
     __ Addu(elements, elements,
             Operand(FixedDoubleArray::kHeaderSize - kHeapObjectTag));
   }
 
-  __ lw(scratch, MemOperand(elements, sizeof(kHoleNanLower32)));
-  DeoptimizeIf(eq, instr->environment(), scratch, Operand(kHoleNanUpper32));
+  if (instr->hydrogen()->RequiresHoleCheck()) {
+    __ lw(scratch, MemOperand(elements, sizeof(kHoleNanLower32)));
+    DeoptimizeIf(eq, instr->environment(), scratch, Operand(kHoleNanUpper32));
+  }
 
   __ ldc1(result, MemOperand(elements));
 }
 
 
 void LCodeGen::DoLoadKeyedSpecializedArrayElement(
     LLoadKeyedSpecializedArrayElement* instr) {
   Register external_pointer = ToRegister(instr->external_pointer());
   Register key = no_reg;
   ElementsKind elements_kind = instr->elements_kind();
@@ skipping 59 matching lines @@
         // TODO(danno): we could be more clever here, perhaps having a special
         // version of the stub that detects if the overflow case actually
         // happens, and generate code that returns a double rather than int.
         DeoptimizeIf(Ugreater_equal, instr->environment(),
             result, Operand(0x80000000));
         break;
       case EXTERNAL_FLOAT_ELEMENTS:
       case EXTERNAL_DOUBLE_ELEMENTS:
       case FAST_DOUBLE_ELEMENTS:
       case FAST_ELEMENTS:
-      case FAST_SMI_ONLY_ELEMENTS:
+      case FAST_SMI_ELEMENTS:
+      case FAST_HOLEY_DOUBLE_ELEMENTS:
+      case FAST_HOLEY_ELEMENTS:
+      case FAST_HOLEY_SMI_ELEMENTS:
       case DICTIONARY_ELEMENTS:
       case NON_STRICT_ARGUMENTS_ELEMENTS:
         UNREACHABLE();
         break;
     }
   }
 }
 
 
 void LCodeGen::DoLoadKeyedGeneric(LLoadKeyedGeneric* instr) {
@@ skipping 997 matching lines @@
         __ sh(value, mem_operand);
         break;
       case EXTERNAL_INT_ELEMENTS:
       case EXTERNAL_UNSIGNED_INT_ELEMENTS:
         __ sw(value, mem_operand);
         break;
       case EXTERNAL_FLOAT_ELEMENTS:
       case EXTERNAL_DOUBLE_ELEMENTS:
       case FAST_DOUBLE_ELEMENTS:
       case FAST_ELEMENTS:
-      case FAST_SMI_ONLY_ELEMENTS:
+      case FAST_SMI_ELEMENTS:
+      case FAST_HOLEY_DOUBLE_ELEMENTS:
+      case FAST_HOLEY_ELEMENTS:
+      case FAST_HOLEY_SMI_ELEMENTS:
       case DICTIONARY_ELEMENTS:
       case NON_STRICT_ARGUMENTS_ELEMENTS:
         UNREACHABLE();
         break;
     }
   }
 }
 
 void LCodeGen::DoStoreKeyedGeneric(LStoreKeyedGeneric* instr) {
   ASSERT(ToRegister(instr->object()).is(a2));
@@ skipping 17 matching lines @@
   ElementsKind from_kind = from_map->elements_kind();
   ElementsKind to_kind = to_map->elements_kind();
 
   __ mov(ToRegister(instr->result()), object_reg);
 
   Label not_applicable;
   __ lw(scratch, FieldMemOperand(object_reg, HeapObject::kMapOffset));
   __ Branch(&not_applicable, ne, scratch, Operand(from_map));
 
   __ li(new_map_reg, Operand(to_map));
-  if (from_kind == FAST_SMI_ONLY_ELEMENTS && to_kind == FAST_ELEMENTS) {
+  if (IsFastSmiElementsKind(from_kind) && IsFastObjectElementsKind(to_kind)) {
     __ sw(new_map_reg, FieldMemOperand(object_reg, HeapObject::kMapOffset));
     // Write barrier.
     __ RecordWriteField(object_reg, HeapObject::kMapOffset, new_map_reg,
                         scratch, kRAHasBeenSaved, kDontSaveFPRegs);
-  } else if (from_kind == FAST_SMI_ONLY_ELEMENTS &&
-      to_kind == FAST_DOUBLE_ELEMENTS) {
+  } else if (IsFastSmiElementsKind(from_kind) &&
+             IsFastDoubleElementsKind(to_kind)) {
     Register fixed_object_reg = ToRegister(instr->temp_reg());
     ASSERT(fixed_object_reg.is(a2));
     ASSERT(new_map_reg.is(a3));
     __ mov(fixed_object_reg, object_reg);
     CallCode(isolate()->builtins()->TransitionElementsSmiToDouble(),
              RelocInfo::CODE_TARGET, instr);
-  } else if (from_kind == FAST_DOUBLE_ELEMENTS && to_kind == FAST_ELEMENTS) {
+  } else if (IsFastDoubleElementsKind(from_kind) &&
+             IsFastObjectElementsKind(to_kind)) {
     Register fixed_object_reg = ToRegister(instr->temp_reg());
     ASSERT(fixed_object_reg.is(a2));
     ASSERT(new_map_reg.is(a3));
     __ mov(fixed_object_reg, object_reg);
     CallCode(isolate()->builtins()->TransitionElementsDoubleToObject(),
              RelocInfo::CODE_TARGET, instr);
   } else {
     UNREACHABLE();
   }
   __ bind(&not_applicable);
@@ skipping 734 matching lines @@
 }
 
 
 void LCodeGen::DoArrayLiteral(LArrayLiteral* instr) {
   Heap* heap = isolate()->heap();
   ElementsKind boilerplate_elements_kind =
       instr->hydrogen()->boilerplate_elements_kind();
 
   // Deopt if the array literal boilerplate ElementsKind is of a type different
   // than the expected one. The check isn't necessary if the boilerplate has
-  // already been converted to FAST_ELEMENTS.
-  if (boilerplate_elements_kind != FAST_ELEMENTS) {
+  // already been converted to TERMINAL_FAST_ELEMENTS_KIND.
+  if (CanTransitionToMoreGeneralFastElementsKind(
+          boilerplate_elements_kind, true)) {
     __ LoadHeapObject(a1, instr->hydrogen()->boilerplate_object());
     // Load map into a2.
     __ lw(a2, FieldMemOperand(a1, HeapObject::kMapOffset));
     // Load the map's "bit field 2".
     __ lbu(a2, FieldMemOperand(a2, Map::kBitField2Offset));
     // Retrieve elements_kind from bit field 2.
     __ Ext(a2, a2, Map::kElementsKindShift, Map::kElementsKindBitCount);
     DeoptimizeIf(ne,
                  instr->environment(),
                  a2,
@@ skipping 132 matching lines @@
     }
   }
 }
 
 
 void LCodeGen::DoFastLiteral(LFastLiteral* instr) {
   int size = instr->hydrogen()->total_size();
   ElementsKind boilerplate_elements_kind =
       instr->hydrogen()->boilerplate()->GetElementsKind();
 
-  // Deopt if the literal boilerplate ElementsKind is of a type different than
-  // the expected one. The check isn't necessary if the boilerplate has already
-  // been converted to FAST_ELEMENTS.
-  if (boilerplate_elements_kind != FAST_ELEMENTS) {
+  // Deopt if the array literal boilerplate ElementsKind is of a type different
+  // than the expected one. The check isn't necessary if the boilerplate has
+  // already been converted to TERMINAL_FAST_ELEMENTS_KIND.
+  if (CanTransitionToMoreGeneralFastElementsKind(
+          boilerplate_elements_kind, true)) {
     __ LoadHeapObject(a1, instr->hydrogen()->boilerplate());
     // Load map into a2.
     __ lw(a2, FieldMemOperand(a1, HeapObject::kMapOffset));
     // Load the map's "bit field 2".
     __ lbu(a2, FieldMemOperand(a2, Map::kBitField2Offset));
     // Retrieve elements_kind from bit field 2.
     __ Ext(a2, a2, Map::kElementsKindShift, Map::kElementsKindBitCount);
     DeoptimizeIf(ne, instr->environment(), a2,
         Operand(boilerplate_elements_kind));
   }
@@ skipping 504 matching lines @@
   __ Subu(scratch, result, scratch);
   __ lw(result, FieldMemOperand(scratch,
                                 FixedArray::kHeaderSize - kPointerSize));
   __ bind(&done);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal