Cumulative thread allocation stats

Provide API to return allocation bytes since the start of VM. Return
false if the sum rolls over.

Signed-off-by: Aleksandar Micic <[email protected]>

Author: Aleksandar Micic

gc/stats/AllocationStats.cpp

@@ -26,6 +26,10 @@
 void
 MM_AllocationStats::clear()
 {
+	/* calculate cumulative stats before any clear */
+	_allocationBytesCumulative += bytesAllocated();
+
+
 #if defined(OMR_GC_THREAD_LOCAL_HEAP)
 	_tlhRefreshCountFresh = 0;
 	_tlhRefreshCountReused = 0;

gc/stats/AllocationStats.hpp

@@ -49,6 +49,7 @@ class MM_AllocationStats : public MM_Base
 
 	uintptr_t _allocationCount;
 	uintptr_t _allocationBytes;
+	uintptr_t _allocationBytesCumulative;   /**< cumulative allocation up to last clear, excluding since last clear */
 	uintptr_t _ownableSynchronizerObjectCount;  /**< Number of Ownable Synchronizer Object allocations */
 	uintptr_t _continuationObjectCount;  /**< Number of Continuation Object allocations */
 	uintptr_t _discardedBytes;
@@ -86,6 +87,18 @@ class MM_AllocationStats : public MM_Base
 		return totalBytesAllocated;
 	}
 
+	bool bytesAllocatedCumulative(uintptr_t *cumulativeValue) {
+		if (NULL != cumulativeValue) {
+			/* sum the values up to last clear and since last clear */
+			*cumulativeValue = _allocationBytesCumulative + bytesAllocated();
+
+			/* return false if overflowing */
+			return (_allocationBytesCumulative <= *cumulativeValue);
+		}
+
+		return false;
+	}
+
 	MM_AllocationStats() :
 #if defined(OMR_GC_THREAD_LOCAL_HEAP)
 		_tlhRefreshCountFresh(0),