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Arm Compiler armasm User Guide : T32 code size diagnostics

T32 code size diagnostics

In T32 code, some instructions, for example a branch or LDR (PC-relative), can be encoded as either a 32-bit or 16-bit instruction. armasm chooses the size of the instruction encoding.

armasm can issue a warning when it assembles a T32 instruction to a 32-bit encoding when it could have used a 16-bit encoding.

To enable this warning, use the --diag_warning 1813 command-line option when invoking armasm.