3.7 Predeclared core register names in AArch32 state

Many of the core register names have synonyms.

The following table shows the predeclared core registers:

Table 3-2 Predeclared core registers in AArch32 state

Register names Meaning
r0-r15 and R0-R15 General purpose registers.
a1-a4 Argument, result or scratch registers. These are synonyms for R0 to R3.
v1-v8 Variable registers. These are synonyms for R4 to R11.
SB Static base register. This is a synonym for R9.
IP Intra-procedure call scratch register. This is a synonym for R12.
SP Stack pointer. This is a synonym for R13.
LR Link register. This is a synonym for R14.
PC Program counter. This is a synonym for R15.

With the exception of a1-a4 and v1-v8, you can write the register names either in all upper case or all lower case.

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