// Test that buffer of array does not move during compaction if fixed keyword applied.
static bool TestCompactionForNotFixedArray()
{
bool retVal = true;
// First we create objects and holes that keeps some space that could be used by compaction.
// Small count so compaction does not happen.
object[] arrayOfArrays = new object[10];
RunAllocations(arrayOfArrays);
// This is the array that we expect to move in during compaction.
int[] testNativeBuffer = new int[100];
// Fill it, so it is not optimized out
for (int i = 0; i < testNativeBuffer.Length; i++)
{
testNativeBuffer[i] = i;
}
// Address before compaction
uint addrBeforeCompaction = TestBasicTypes.Get_Buffer_Address_Array(testNativeBuffer);
// Causes compaction.
InitiateCompactoin();
// Address after compaction.
uint addrAfterCompaction = TestBasicTypes.Get_Buffer_Address_Array(testNativeBuffer);
// Should be different addresses.
retVal = addrBeforeCompaction != addrAfterCompaction;
if (retVal)
{
Debug.Print("Testing of buffer move during compaction succeeded");
}
else
{
Debug.Print("Testing of fixed keyword failed");
}
return(retVal);
}
// Test that buffer of array actually moves during compaction.
unsafe static bool TestCompactionForFixedArray()
{
bool retVal = true;
// First we create objects and holes that keeps some space that could be used by compaction.
// Small count so compaction does not happen.
object[] arrayOfArrays = new object[10];
RunAllocations(arrayOfArrays);
// This is the array that we expect to move in during compaction.
int[] testNativeBuffer = new int[100];
// Fill it, so it is not optimized out
for (int i = 0; i < testNativeBuffer.Length; i++)
{
testNativeBuffer[i] = i;
}
fixed(int *pFixedArray = testNativeBuffer)
{
// Address before compaction
uint addrBeforeCompaction = TestBasicTypes.Get_Buffer_Address_Array(testNativeBuffer);
// Causes compaction.
InitiateCompactoin();
// Address after compaction.
uint addrAfterCompaction = TestBasicTypes.Get_Buffer_Address_Array(testNativeBuffer);
// Should be equal addresses, becuase array was pinned.
retVal = addrBeforeCompaction == addrAfterCompaction;
// Check that access to the buffer through the reference is the same as through array
for (int i = 0; i < testNativeBuffer.Length; i++)
{
retVal = retVal && (pFixedArray[i] == testNativeBuffer[i]);
}
// Update the data of array through reference, then check that it was updated properly
Random random = new Random();
for (int i = 0; i < testNativeBuffer.Length; i++)
{
int value = 2 * random.Next();
pFixedArray[i] = value;
// Check that value is set properly and can be accessed through reference and array
if (pFixedArray[i] != value || testNativeBuffer[i] != value)
{
retVal = false;
}
}
// Test that access through *pFixedArray is the same as pFixedArray[0];
*pFixedArray = 2 * random.Next();
if (pFixedArray[0] != *pFixedArray || testNativeBuffer[0] != *pFixedArray)
{
retVal = false;
}
}
// Since we exited "fixed" block, the testNativeBuffer is now movable.
// It is very important to see that now buffer moves, this is the prove that it was unpinned. .
uint addrBeforeCompaction1 = TestBasicTypes.Get_Buffer_Address_Array(testNativeBuffer);
InitiateCompactoin();
uint addrAfterCompaction1 = TestBasicTypes.Get_Buffer_Address_Array(testNativeBuffer);
// Verifies that now buffer moved.
retVal = retVal && (addrBeforeCompaction1 != addrAfterCompaction1);
if (retVal)
{
Debug.Print("Testing of fixed keyword succeded");
}
else
{
Debug.Print("Testing of fixed keyword failed");
}
return(retVal);
}
