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Which instruction format does Cortex-R support,encoding A1 orA2?

I see it support encoding T2 for Thumb-2 instruction set.But which instruction format does Cortex-R support for ARM instruction,encoding A1 orA2?

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  • Hi,

    > Encoding A1 and A2 have different range of immediate constants.And,I want to know

    > the rang of operand 2 for MOV for Cortex.It's useful for program,isn't it?

    Note that for this case there is an applicable syntax for A1 and A2.

    If you write:

        MOV Rd, #<const>

    ... the A1 format would be used, and <const> must not exceed the 12-bit range. If <const> is too large, the compiler/assembler would generate an error and advise you to use the MOVW syntax.

    If you write:

        MOVW Rd, #<const>

    ... the A2 format would be ued, and the range for <const> can be 16-bit.

    Xingguang