38-8 Vol. 3D
ENCLAVE ACCESS CONTROL AND DATA STRUCTURES
38.9.1 GPRSGX
Region
The layout of the GPRSGX region is shown in Table 38-8.
38.9.1.1 EXITINFO
EXITINFO contains the information used to report exit reasons to software inside the enclave. It is a 4 byte field laid
out as in Table 38-9. The VALID bit is set only for the exceptions conditions which are reported inside an enclave.
See Table 38-10 for which exceptions are reported inside the enclave. If the exception condition is not one reported
inside the enclave then VECTOR and EXIT_TYPE are cleared.
Table 38-8. Layout of GPRSGX Portion of the State Save Area
Field
OFFSET (Bytes) Size (Bytes)
Description
RAX
0
8
RCX
8
8
RDX
16
8
RBX
24
8
RSP
32
8
RBP
40
8
RSI
48
8
RDI
56
8
R8
64
8
R9
72
8
R10
80
8
R11
88
8
R12
96
8
R13
104
8
R14
112
8
R15
120
8
RFLAGS
128
8
Flag register.
RIP
136
8
Instruction pointer.
URSP
144
8
Non-Enclave (outside) stack pointer. Saved by EENTER, restored on AEX.
URBP
152
8
Non-Enclave (outside) RBP pointer. Saved by EENTER, restored on AEX.
EXITINFO
160
4
Contains information about exceptions that cause AEXs, which might be
needed by enclave software (see Section 38.9.1.1).
RESERVED
164
4
FSBASE
168
8
FS BASE.
GSBASE
176
8
GS BASE.