4.8.7 Registers

In addition, control register names are predefined symbols.

The names of ARM registers and their aliases are register symbols, including:

Table 4-3 ARM Register Symbols with Aliases

Register Name Alias Register Name Alias
R0 A1 R8 V5
R1 A2 R9 V6
R2 A3 R10 V7
R3 A4 R11 V8
R4 V1 R12 V9, IP
R5 V2 R13 SP
R6 V3 R14 LR
R7 V4, AP R15 PC

Register symbols and aliases can be entered as all uppercase or all lowercase characters. For example, R13 could also be entered as r13, SP, or sp.

Control register symbols can be entered in all upper-case or all lower-case characters.

See the "Register Conventions" section of the ARM Optimizing C/C++ Compiler User's Guide for details about the registers and their uses.

Status registers can be entered as all uppercase or all lowercase characters; that is, CPSR could also be entered as cpsr, CPSR_ALL, or cpsr_all.

Table 4-4 ARM Status Registers and Aliases

Register Alias Description
CPSR CPSR_ALL Current processor status register
CPSR_FLG Current processor status register flag bits only
SPSR SPSR_ALL Saved processor status register
SPSR_FLG Saved processor status register flag bits only