This mask is to control Heap Guard behavior.
Note:
a) Heap Guard is for debug purpose and should not be enabled in product
BIOS.
b) Due to the limit of pool memory implementation and the alignment
requirement of UEFI spec, BIT7 is a try-best setting which cannot
guarantee that the returned pool is exactly adjacent to head guard
page or tail guard page.
c) UEFI freed-memory guard and UEFI pool/page guard cannot be enabled
at the same time.
BIT0 - Enable UEFI page guard.

BIT1 - Enable UEFI pool guard.

BIT2 - Enable SMM page guard.

BIT3 - Enable SMM pool guard.

BIT4 - Enable UEFI freed-memory guard (Use-After-Free memory detection).

BIT6 - Enable non-stop mode.

BIT7 - The direction of Guard Page for Pool Guard.
0 - The returned pool is near the tail guard page.

1 - The returned pool is near the head guard page.

The Heap Guard feature mask

PCD Information

Name	Token Space	Token number	Data Type	Default Value
PcdHeapGuardPropertyMask	gEfiMdeModulePkgTokenSpaceGuid	0x30001054	UINT8	0x0