Thumb Instruction Referenc e
5-30 Copyright © 2000, 2001 ARM Limited. A ll rights reserved. ARM DUI 0068B
5.3.5 TST
Test bi ts.
Syntax
TST Rn, Rm
where:
Rn
is the register containing the first operand.
Rm
is the register containing the second operand.
Usage
This instruction performs a bitwise logical AND operation on the values in
Rm
and
Rn
. It
updates the condition flags, but does not place a result in a register.
Restrictions
Rn
and
Rm
must be in the range
r0
-
r7
.
Condition flags
This instruction updates the N and Z flags according to the result. The C and V flags are
unaffected.
Architectures
This instruction is available in all T variants of the ARM architecture.
Example
TST r2,r4