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Is there a reason why banked registers SP and LR can't be accessed as r13_<mode> or r14_<mode>, but
one has to use SP_<mode> or LR_<mode> instead? It makes macros and inline assembly difficult.
In document (ARMv7-A/R ARM Issue C) it says:
Software using an MRS (Banked register) or MSR (Banked register) instruction specifies one of these registers using a name shown in Figure B9-1, or an alternative name for SP or LR.
Software using an MRS (Banked register) or MSR (Banked register) instruction specifies one of these registers using a
name shown in Figure B9-1, or an alternative name for SP or LR.
But in both the figure and the text the names are the same: SP or LR. There is no alternative.
It is weird, especially when the destination register can be r13, r14 or r15 as well as sp, lr or pc.