Update Assembler::TryAllocate to support inline allocation tracing

runtime/vm/assembler_mips.cc

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/globals.h"  // NOLINT
 #if defined(TARGET_ARCH_MIPS)
 
 #include "vm/assembler.h"
 #include "vm/longjump.h"
 #include "vm/runtime_entry.h"
@@ skipping 872 matching lines @@
     lw(TMP, Address(temp_reg, count_field_offset));
     AddImmediate(TMP, 1);
     sw(TMP, Address(temp_reg, count_field_offset));
     lw(TMP, Address(temp_reg, size_field_offset));
     addu(TMP, TMP, size_reg);
     sw(TMP, Address(temp_reg, size_field_offset));
   }
 }
 
 
+void Assembler::MaybeTraceAllocation(intptr_t cid,
+                                     Register temp_reg,
+                                     Label* trace) {
+  ASSERT(cid > 0);
+  ASSERT(!in_delay_slot_);
+  ASSERT(temp_reg != kNoRegister);
+  ASSERT(temp_reg != TMP);
+  Isolate* isolate = Isolate::Current();
+  ClassTable* class_table = isolate->class_table();
+  const uword class_offset = cid * sizeof(ClassHeapStats);  // NOLINT
+  if (cid < kNumPredefinedCids) {
+    const uword class_heap_stats_table_address =
+        class_table->PredefinedClassHeapStatsTableAddress();
+    LoadImmediate(temp_reg, class_heap_stats_table_address + class_offset);
+  } else {
+    LoadImmediate(temp_reg, class_table->ClassStatsTableAddress());
+    lw(temp_reg, Address(temp_reg, 0));
+    AddImmediate(temp_reg, class_offset);
+  }
+  const uword state_offset = ClassHeapStats::state_offset();
+  const Address& state_address = Address(temp_reg, state_offset);
+  lw(temp_reg, state_address);
+  andi(CMPRES1, temp_reg, Immediate(ClassHeapStats::TraceAllocationMask()));
+  bne(CMPRES1, ZR, trace);
+}
+
+
 void Assembler::TryAllocate(const Class& cls,
                             Label* failure,
                             Register instance_reg,
                             Register temp_reg) {
   ASSERT(!in_delay_slot_);
   ASSERT(failure != NULL);
   if (FLAG_inline_alloc) {
+    // If this allocation is traced, program will jump to failure path
+    // (i.e. the allocation stub) which will allocate the object and trace the
+    // allocation call site.
+    MaybeTraceAllocation(cls.id(), temp_reg, failure);
     const intptr_t instance_size = cls.instance_size();
     Heap* heap = Isolate::Current()->heap();
     Heap::Space space = heap->SpaceForAllocation(cls.id());
     const uword top_address = heap->TopAddress(space);
     LoadImmediate(temp_reg, top_address);
     lw(instance_reg, Address(temp_reg));
     // TODO(koda): Protect against unsigned overflow here.
     AddImmediate(instance_reg, instance_size);
 
     // instance_reg: potential next object start.
@@ skipping 332 matching lines @@
   Label stop;
   b(&stop);
   Emit(reinterpret_cast<int32_t>(message));
   Bind(&stop);
   break_(Instr::kStopMessageCode);
 }
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_MIPS