Synchronization.c

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#include <Library/DebugLib.h>
 
UINT32
EFIAPI
AsmInternalSyncCompareExchange16 (
  IN volatile UINT32 *,
  IN UINT64,
  IN UINT64,
  IN UINT64
  );
 
UINT32
EFIAPI
AsmInternalSyncCompareExchange32 (
  IN volatile UINT32 *,
  IN UINT64,
  IN UINT64
  );
 
UINT64
EFIAPI
AsmInternalSyncCompareExchange64 (
  IN volatile UINT64 *,
  IN UINT64,
  IN UINT64
  );
 
UINT32
EFIAPI
AsmInternalSyncIncrement (
  IN      volatile UINT32 *
  );
 
UINT32
EFIAPI
AsmInternalSyncDecrement (
  IN      volatile UINT32 *
  );
 
UINT16
EFIAPI
InternalSyncCompareExchange16 (
  IN      volatile UINT16  *Value,
  IN      UINT16           CompareValue,
  IN      UINT16           ExchangeValue
  )
{
  UINT32           RetValue;
  UINT32           Shift;
  UINT64           Mask;
  UINT64           LocalCompareValue;
  UINT64           LocalExchangeValue;
  volatile UINT32  *Ptr32;
 
  /* Check that ptr is naturally aligned */
  ASSERT (!((UINT64)Value & (sizeof (UINT16) - 1)));
 
  /* Mask inputs to the correct size. */
  Mask               = (((~0UL) - (1UL << (0)) + 1) & (~0UL >> (64 - 1 - ((sizeof (UINT16) * 8) - 1))));
  LocalCompareValue  = ((UINT64)CompareValue) & Mask;
  LocalExchangeValue = ((UINT64)ExchangeValue) & Mask;
 
  /*
   * Calculate a shift & mask that correspond to the value we wish to
   * compare & exchange within the naturally aligned 4 byte integer
   * that includes it.
   */
  Shift                = (UINT64)Value & 0x3;
  Shift               *= 8; /* BITS_PER_BYTE */
  LocalCompareValue  <<= Shift;
  LocalExchangeValue <<= Shift;
  Mask               <<= Shift;
 
  /*
   * Calculate a pointer to the naturally aligned 4 byte integer that
   * includes our byte of interest, and load its value.
   */
  Ptr32 = (UINT32 *)((UINT64)Value & ~0x3);
 
  RetValue = AsmInternalSyncCompareExchange16 (
               Ptr32,
               Mask,
               LocalCompareValue,
               LocalExchangeValue
               );
 
  return (RetValue & Mask) >> Shift;
}
 
UINT32
EFIAPI
InternalSyncCompareExchange32 (
  IN      volatile UINT32  *Value,
  IN      UINT32           CompareValue,
  IN      UINT32           ExchangeValue
  )
{
  UINT32  RetValue;
 
  RetValue = AsmInternalSyncCompareExchange32 (
               Value,
               CompareValue,
               ExchangeValue
               );
 
  return RetValue;
}
 
UINT64
EFIAPI
InternalSyncCompareExchange64 (
  IN      volatile UINT64  *Value,
  IN      UINT64           CompareValue,
  IN      UINT64           ExchangeValue
  )
{
  UINT64  RetValue;
 
  RetValue = AsmInternalSyncCompareExchange64 (
               Value,
               CompareValue,
               ExchangeValue
               );
 
  return RetValue;
}
 
UINT32
EFIAPI
InternalSyncIncrement (
  IN      volatile UINT32  *Value
  )
{
  return AsmInternalSyncIncrement (Value);
}
 
UINT32
EFIAPI
InternalSyncDecrement (
  IN      volatile UINT32  *Value
  )
{
  return AsmInternalSyncDecrement (Value);
}