Cardmarking writebarrier.

src/arm/codegen-arm.cc

 // Copyright 2010 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 2258 matching lines @@
   // the object)
   __ mov(r1, Operand(r0));
   __ ldr(r1, FieldMemOperand(r1, Map::kInstanceDescriptorsOffset));
   __ ldr(r1, FieldMemOperand(r1, DescriptorArray::kEnumerationIndexOffset));
   __ ldr(r2,
          FieldMemOperand(r1, DescriptorArray::kEnumCacheBridgeCacheOffset));
 
   frame_->EmitPush(r0);  // map
   frame_->EmitPush(r2);  // enum cache bridge cache
   __ ldr(r0, FieldMemOperand(r2, FixedArray::kLengthOffset));
-  __ mov(r0, Operand(r0, LSL, kSmiTagSize));
   frame_->EmitPush(r0);
   __ mov(r0, Operand(Smi::FromInt(0)));
   frame_->EmitPush(r0);
   entry.Jump();
 
   fixed_array.Bind();
   __ mov(r1, Operand(Smi::FromInt(0)));
   frame_->EmitPush(r1);  // insert 0 in place of Map
   frame_->EmitPush(r0);
 
   // Push the length of the array and the initial index onto the stack.
   __ ldr(r0, FieldMemOperand(r0, FixedArray::kLengthOffset));
-  __ mov(r0, Operand(r0, LSL, kSmiTagSize));
   frame_->EmitPush(r0);
   __ mov(r0, Operand(Smi::FromInt(0)));  // init index
   frame_->EmitPush(r0);
 
   // Condition.
   entry.Bind();
   // sp[0] : index
   // sp[1] : array/enum cache length
   // sp[2] : array or enum cache
   // sp[3] : 0 or map
@@ skipping 2180 matching lines @@
 
     // Fill out the elements FixedArray.
     // r0: JSArray, tagged.
     // r3: FixedArray, tagged.
     // r5: Number of elements in array, untagged.
 
     // Set map.
     __ mov(r2, Operand(Factory::fixed_array_map()));
     __ str(r2, FieldMemOperand(r3, HeapObject::kMapOffset));
     // Set FixedArray length.
-    __ str(r5, FieldMemOperand(r3, FixedArray::kLengthOffset));
+    __ mov(r6, Operand(r5, LSL, kSmiTagSize));
+    __ str(r6, FieldMemOperand(r3, FixedArray::kLengthOffset));
     // Fill contents of fixed-array with the-hole.
     __ mov(r2, Operand(Factory::the_hole_value()));
     __ add(r3, r3, Operand(FixedArray::kHeaderSize - kHeapObjectTag));
     // Fill fixed array elements with hole.
     // r0: JSArray, tagged.
     // r2: the hole.
     // r3: Start of elements in FixedArray.
     // r5: Number of elements to fill.
     Label loop;
     __ tst(r5, Operand(r5));
@@ skipping 1186 matching lines @@
       // is not a dictionary.
       __ ldr(scratch1, FieldMemOperand(receiver, JSObject::kElementsOffset));
       __ ldr(scratch2, FieldMemOperand(scratch1, JSObject::kMapOffset));
       __ LoadRoot(ip, Heap::kFixedArrayMapRootIndex);
       __ cmp(scratch2, ip);
       deferred->Branch(ne);
 
       // Check that key is within bounds. Use unsigned comparison to handle
       // negative keys.
       __ ldr(scratch2, FieldMemOperand(scratch1, FixedArray::kLengthOffset));
-      __ cmp(scratch2, Operand(key, ASR, kSmiTagSize));
+      __ cmp(scratch2, key);
       deferred->Branch(ls);  // Unsigned less equal.
 
       // Load and check that the result is not the hole (key is a smi).
       __ LoadRoot(scratch2, Heap::kTheHoleValueRootIndex);
       __ add(scratch1,
              scratch1,
              Operand(FixedArray::kHeaderSize - kHeapObjectTag));
       __ ldr(scratch1,
              MemOperand(scratch1, key, LSL,
                         kPointerSizeLog2 - (kSmiTagSize + kSmiShiftSize)));
@@ skipping 280 matching lines @@
                         r2,
                         &gc,
                         TAG_OBJECT);
 
   // Load the function from the stack.
   __ ldr(r3, MemOperand(sp, 0));
 
   // Setup the object header.
   __ LoadRoot(r2, Heap::kContextMapRootIndex);
   __ str(r2, FieldMemOperand(r0, HeapObject::kMapOffset));
-  __ mov(r2, Operand(length));
-  __ str(r2, FieldMemOperand(r0, Array::kLengthOffset));
+  __ mov(r2, Operand(Smi::FromInt(length)));
+  __ str(r2, FieldMemOperand(r0, FixedArray::kLengthOffset));
 
   // Setup the fixed slots.
   __ mov(r1, Operand(Smi::FromInt(0)));
   __ str(r3, MemOperand(r0, Context::SlotOffset(Context::CLOSURE_INDEX)));
   __ str(r0, MemOperand(r0, Context::SlotOffset(Context::FCONTEXT_INDEX)));
   __ str(r1, MemOperand(r0, Context::SlotOffset(Context::PREVIOUS_INDEX)));
   __ str(r1, MemOperand(r0, Context::SlotOffset(Context::EXTENSION_INDEX)));
 
   // Copy the global object from the surrounding context.
   __ ldr(r1, MemOperand(cp, Context::SlotOffset(Context::GLOBAL_INDEX)));
@@ skipping 610 matching lines @@
   // Use of registers. Register result is used as a temporary.
   Register number_string_cache = result;
   Register mask = scratch3;
 
   // Load the number string cache.
   __ LoadRoot(number_string_cache, Heap::kNumberStringCacheRootIndex);
 
   // Make the hash mask from the length of the number string cache. It
   // contains two elements (number and string) for each cache entry.
   __ ldr(mask, FieldMemOperand(number_string_cache, FixedArray::kLengthOffset));
-  // Divide length by two (length is not a smi).
-  __ mov(mask, Operand(mask, ASR, 1));
+  // Divide length by two (length is a smi).
+  __ mov(mask, Operand(mask, ASR, kSmiTagSize + 1));
   __ sub(mask, mask, Operand(1));  // Make mask.
 
   // Calculate the entry in the number string cache. The hash value in the
   // number string cache for smis is just the smi value, and the hash for
   // doubles is the xor of the upper and lower words. See
   // Heap::GetNumberStringCache.
   Label is_smi;
   Label load_result_from_cache;
   if (!object_is_smi) {
     __ BranchOnSmi(object, &is_smi);
@@ skipping 1870 matching lines @@
   // Get the length (smi tagged) and set that as an in-object property too.
   ASSERT(Heap::arguments_length_index == 1);
   __ ldr(r1, MemOperand(sp, 0 * kPointerSize));
   __ str(r1, FieldMemOperand(r0, JSObject::kHeaderSize + kPointerSize));
 
   // If there are no actual arguments, we're done.
   Label done;
   __ cmp(r1, Operand(0));
   __ b(eq, &done);
 
-  // Get the parameters pointer from the stack and untag the length.
+  // Get the parameters pointer from the stack.
   __ ldr(r2, MemOperand(sp, 1 * kPointerSize));
-  __ mov(r1, Operand(r1, LSR, kSmiTagSize));
 
   // Setup the elements pointer in the allocated arguments object and
   // initialize the header in the elements fixed array.
   __ add(r4, r0, Operand(Heap::kArgumentsObjectSize));
   __ str(r4, FieldMemOperand(r0, JSObject::kElementsOffset));
   __ LoadRoot(r3, Heap::kFixedArrayMapRootIndex);
   __ str(r3, FieldMemOperand(r4, FixedArray::kMapOffset));
   __ str(r1, FieldMemOperand(r4, FixedArray::kLengthOffset));
+  __ mov(r1, Operand(r1, LSR, kSmiTagSize));  // Untag the length for the loop.
 
   // Copy the fixed array slots.
   Label loop;
   // Setup r4 to point to the first array slot.
   __ add(r4, r4, Operand(FixedArray::kHeaderSize - kHeapObjectTag));
   __ bind(&loop);
   // Pre-decrement r2 with kPointerSize on each iteration.
   // Pre-decrement in order to skip receiver.
   __ ldr(r3, MemOperand(r2, kPointerSize, NegPreIndex));
   // Post-increment r4 with kPointerSize on each iteration.
@@ skipping 130 matching lines @@
          FieldMemOperand(r0, JSArray::kElementsOffset));
   __ ldr(r0, FieldMemOperand(last_match_info_elements, HeapObject::kMapOffset));
   __ LoadRoot(ip, Heap::kFixedArrayMapRootIndex);
   __ cmp(r0, ip);
   __ b(ne, &runtime);
   // Check that the last match info has space for the capture registers and the
   // additional information.
   __ ldr(r0,
          FieldMemOperand(last_match_info_elements, FixedArray::kLengthOffset));
   __ add(r2, r2, Operand(RegExpImpl::kLastMatchOverhead));
-  __ cmp(r2, r0);
+  __ cmp(r2, Operand(r0, ASR, kSmiTagSize));
   __ b(gt, &runtime);
 
   // subject: Subject string
   // regexp_data: RegExp data (FixedArray)
   // Check the representation and encoding of the subject string.
   Label seq_string;
   const int kStringRepresentationEncodingMask =
       kIsNotStringMask | kStringRepresentationMask | kStringEncodingMask;
   __ ldr(r0, FieldMemOperand(subject, HeapObject::kMapOffset));
   __ ldrb(r0, FieldMemOperand(r0, Map::kInstanceTypeOffset));
@@ skipping 1342 matching lines @@
   __ bind(&string_add_runtime);
   __ TailCallRuntime(Runtime::kStringAdd, 2, 1);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_ARM