Arm VERSION 1.2 Instrukcja Użytkownika Strona 192

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ARM Instruction Reference
4-82 Copyright © 2000, 2001 ARM Limited. All rights reserved. ARM DUI 0068B
4.9.3 LDR ARM pseudo-instruction
Load a register with either:
a 32-bit constant value
an address.
Note
This section describes the
LDR
pseudo-instruction only. See ARM memory access
instructions on page 4-6 for information on the
LDR
instruction.
Syntax
LDR{cond} register,=[expr | label-expr]
where:
cond
is an optional condition code.
register
is the register to be loaded.
expr
evaluates to a numeric constant:
the assembler generates a
MOV
or
MVN
instruction, if the value of
expr
is within range
if the value of
expr
is not within range of a
MOV
or
MVN
instruction,
the assembler places the constant in a literal pool and generates a
program-relative
LDR
instruction that reads the constant from the
literal pool.
label-expr
is a program-relative or external expression. The assembler places the
value of
label-expr
in a literal pool and generates a program-relative
LDR
instruction that loads the value from the literal pool.
If
label-expr
is an external expression, or is not contained in the current
section, the assembler places a linker relocation directive in the object
file. The linker generates the address at link time.
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