EPXA4 Datasheet, PDF (34/34 Pages) Altera Corporation – Excalibur Devices

Errata Sheet - Appendix A
Examples:
MOV(S) PC, Rm, <SHIFTOP> Rs
ADD(S) PC, Rn, Rm, <SHIFTOP> Rs
The only theoretical use for these instructions which has been suggested
would be for a branch table that was organised in powers of 2.
MOV
MOV
ADD
0x1004:
0x1008 -> 0x100C:
0x1010 -> 0x101C:
0x1020 -> 0x103C:
0x1040 -> 0x107C:
0x1080 -> 0x10FC:
0x1100 -> 0x11FC:
0x1200 -> 0x13FC:
r0,#0x100
r1,#0x4
PC,r0,r1, LSL r2
Code seq1 : 1 instruction
Code seq2:2 instructions
Code seq3:4 instructions
Code seq4:8 instructions
Code seq5:16 instructions
Code seq6:32 instructions
Code seq7:64 instructions
Code seq8:128 instructions
To date ARM knows of no examples of an application for a branch table
organised in such a manner. However, if one was required then an
alternative code sequence could be used.
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