ARM Instruction Reference
ARM DUI 0068B
Copyright © 2000, 2001 ARM Limited. All rights reserved.
4-33
Use of r15
If you use r15 as
Rn
, the value used is the address of the instruction plus 8.
If you use r15 as
Rd
:
•
Execution branches to the address corresponding to the result.
•
If you use the
S
suffix, the SPSR of the current mode is copied to the CPSR. You
can use this to return from exceptions (see the
Handling Processor Exceptions
chapter in
ADS Developer Guide
).
Caution
Do not use the
S
suffix when using r15 as
Rd
in User mode or System mode. The effect
of such an instruction is unpredictable, but the assembler cannot warn you at assembly
time.
You cannot use r15 for
Rd
or any operand in any data processing instruction that has a
register-controlled shift (see
Flexible second operand
on page 4-24).
Architectures
These instructions are available in all versions of the ARM architecture.
Examples
MOV r5,r2
MVNNE r11,#0xF000000B
MOVS r0,r0,ASR r3
Incorrect examples
MVN r15,r3,ASR r0 ; r15 not allowed with register
; controlled shift
Содержание Developer Suite
Страница 10: ...Preface x Copyright 2000 2001 ARM Limited All rights reserved ARM DUI 0068B ...
Страница 110: ...Assembler Reference 3 32 Copyright 2000 2001 ARM Limited All rights reserved ARM DUI 0068B ...
Страница 185: ...ARM Instruction Reference ARM DUI 0068B Copyright 2000 2001 ARM Limited All rights reserved 4 75 Example MSR CPSR_f r5 ...
Страница 238: ...Thumb Instruction Reference 5 44 Copyright 2000 2001 ARM Limited All rights reserved ARM DUI 0068B ...
Страница 282: ...Vector Floating point Programming 6 44 Copyright 2000 2001 ARM Limited All rights reserved ARM DUI 0068B ...
Страница 360: ...Index Index 6 Copyright 2000 2001 ARM Limited All rights reserved ARM DUI 0068B ...