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A32 and T32 instruction portability diagnostics

armasm can issue warnings about instructions that cannot assemble to both A32 and T32 code.

There are a few UAL instructions that can assemble as either A32 code or T32 code, but not both. You can identify these instructions in the source code using the --diag_warning 1812 command-line option when invoking armasm.

It warns for any instruction that cannot be assembled in the other instruction set. This is only a hint, and other factors, like relocation availability or target distance might affect the accuracy of the message.