1 files changed, 10 insertions, 0 deletions
diff --git a/disas/libvixl/a64/instructions-a64.h b/disas/libvixl/a64/instructions-a64.h
index a4240d7d33..d5b90c52e1 100644
--- a/disas/libvixl/a64/instructions-a64.h
+++ b/disas/libvixl/a64/instructions-a64.h
@@ -41,6 +41,10 @@ const unsigned kLiteralEntrySize = 4;
 const unsigned kLiteralEntrySizeLog2 = 2;
 const unsigned kMaxLoadLiteralRange = 1 * MBytes;
 
+// This is the nominal page size (as used by the adrp instruction); the actual
+// size of the memory pages allocated by the kernel is likely to differ.
+const unsigned kPageSize = 4 * KBytes;
+
 const unsigned kWRegSize = 32;
 const unsigned kWRegSizeLog2 = 5;
 const unsigned kWRegSizeInBytes = kWRegSize / 8;
@@ -79,6 +83,12 @@ const unsigned kZeroRegCode = 31;
 const unsigned kSPRegInternalCode = 63;
 const unsigned kRegCodeMask = 0x1f;
 
+const unsigned kAddressTagOffset = 56;
+const unsigned kAddressTagWidth = 8;
+const uint64_t kAddressTagMask =
+    ((UINT64_C(1) << kAddressTagWidth) - 1) << kAddressTagOffset;
+VIXL_STATIC_ASSERT(kAddressTagMask == UINT64_C(0xff00000000000000));
+
 // AArch64 floating-point specifics. These match IEEE-754.
 const unsigned kDoubleMantissaBits = 52;
 const unsigned kDoubleExponentBits = 11;