The SP_EL0 characteristics are:
Holds the stack pointer associated with EL0. At higher Exception levels, this is used as the current stack pointer when the value of SPSel.SP is 0.
RW fields in this register reset to architecturally UNKNOWN values.
SP_EL0 is a 64-bit register.
The SP_EL0 bit assignments are:
63 | 62 | 61 | 60 | 59 | 58 | 57 | 56 | 55 | 54 | 53 | 52 | 51 | 50 | 49 | 48 | 47 | 46 | 45 | 44 | 43 | 42 | 41 | 40 | 39 | 38 | 37 | 36 | 35 | 34 | 33 | 32 |
Stack pointer | |||||||||||||||||||||||||||||||
Stack pointer | |||||||||||||||||||||||||||||||
31 | 30 | 29 | 28 | 27 | 26 | 25 | 24 | 23 | 22 | 21 | 20 | 19 | 18 | 17 | 16 | 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
Stack pointer.
This field resets to an architecturally UNKNOWN value.
When the value of PSTATE.SP is 0, this register is accessible at all Exception levels as the current stack pointer.
Accesses to this register use the following encodings:
op0 | CRn | op1 | op2 | CRm |
---|---|---|---|---|
0b11 | 0b0100 | 0b000 | 0b000 | 0b0001 |
if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if PSTATE.SP == '0' then UNDEFINED; else return SP_EL0; elsif PSTATE.EL == EL2 then if PSTATE.SP == '0' then UNDEFINED; else return SP_EL0; elsif PSTATE.EL == EL3 then return SP_EL0;
op0 | CRn | op1 | op2 | CRm |
---|---|---|---|---|
0b11 | 0b0100 | 0b000 | 0b000 | 0b0001 |
if PSTATE.EL == EL0 then UNDEFINED; elsif PSTATE.EL == EL1 then if PSTATE.SP == '0' then UNDEFINED; else SP_EL0 = X[t]; elsif PSTATE.EL == EL2 then if PSTATE.SP == '0' then UNDEFINED; else SP_EL0 = X[t]; elsif PSTATE.EL == EL3 then SP_EL0 = X[t];
13/12/2018 16:42; 6379d01c197f1d40720d32d0f84c419c9187c009
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