Move object allocation in new space to macro assembler

src/arm/codegen-arm.cc

Index: src/arm/codegen-arm.cc
===================================================================
--- src/arm/codegen-arm.cc	(revision 2784)
+++ src/arm/codegen-arm.cc	(working copy)
@@ -4945,36 +4945,21 @@
 static void AllocateHeapNumber(
     MacroAssembler* masm,
     Label* need_gc,       // Jump here if young space is full.
-    Register result_reg,  // The tagged address of the new heap number.
-    Register allocation_top_addr_reg,  // A scratch register.
+    Register result,  // The tagged address of the new heap number.
+    Register scratch1,  // A scratch register.
     Register scratch2) {  // Another scratch register.
-  ExternalReference allocation_top =
-      ExternalReference::new_space_allocation_top_address();
-  ExternalReference allocation_limit =
-      ExternalReference::new_space_allocation_limit_address();
+  // Allocate an object in the heap for the heap number and tag it as a heap
+  // object.
+  __ AllocateObjectInNewSpace(HeapNumber::kSize,
+                              result,
+                              scratch1,
+                              scratch2,
+                              need_gc,
+                              true);
 
-  // allocat := the address of the allocation top variable.
-  __ mov(allocation_top_addr_reg, Operand(allocation_top));
-  // result_reg := the old allocation top.
-  __ ldr(result_reg, MemOperand(allocation_top_addr_reg));
-  // scratch2 := the address of the allocation limit.
-  __ mov(scratch2, Operand(allocation_limit));
-  // scratch2 := the allocation limit.
-  __ ldr(scratch2, MemOperand(scratch2));
-  // result_reg := the new allocation top.
-  __ add(result_reg, result_reg, Operand(HeapNumber::kSize));
-  // Compare new new allocation top and limit.
-  __ cmp(result_reg, Operand(scratch2));
-  // Branch if out of space in young generation.
-  __ b(hi, need_gc);
-  // Store new allocation top.
-  __ str(result_reg, MemOperand(allocation_top_addr_reg));  // store new top
-  // Tag and adjust back to start of new object.
-  __ sub(result_reg, result_reg, Operand(HeapNumber::kSize - kHeapObjectTag));
-  // Get heap number map into scratch2.
-  __ LoadRoot(scratch2, Heap::kHeapNumberMapRootIndex);
-  // Store heap number map in new object.
-  __ str(scratch2, FieldMemOperand(result_reg, HeapObject::kMapOffset));
+  // Get heap number map and store it in the allocated object.
+  __ LoadRoot(scratch1, Heap::kHeapNumberMapRootIndex);
+  __ str(scratch1, FieldMemOperand(result, HeapObject::kMapOffset));
 }