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Optional hash

You do not need to specify a hash before immediate constants in any instruction syntax (including ARM, Thumb, Wireless MMX, NEON, and VFP instructions). For example, the following are valid instructions:

    BKPT 100
    MOVT R1, 256
    VCEQ.I8 Q1, Q2, 0    

By default, the assembler warns if you do not specify a hash:

WARNING: A1865W: '#' not seen before constant expression.

This can be suppressed with --diag_suppress=1865.

If you use the assembler code with another assembler, you are advised to use the # before all immediates. The disassembler will always show the # for clarity.