3.6 Predeclared core register names in AArch32 state
Many of the core register names have synonyms.
The following table shows the predeclaredcore registers:
Table 3-2 Predeclared core registers in AArch32 state
General purpose registers.
Argument, result or scratch registers.These are synonyms for R0 to R3.
Variable registers. These are synonymsfor R4 to R11.
Static base register. This is a synonymfor R9.
Intra-procedure call scratch register.This is a synonym for R12.
Stack pointer. This is a synonym forR13.
Link register. This is a synonym forR14.
Program counter. This is a synonym forR15.
With the exception of
v1-v8,you can write the register names either in all upper case or alllower case.