Relationship between RL78 mirror area and linker script for LLVM/GCC
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To allow instructions with 16-bit addresses to be used with const data, thus producing shorter code, the usage of the mirroring feature of the RL78 is recomanded.
We use this for the .rodata section, placing the section at a fixed address in the mirror source address range will result in it being mirrored to the destination address range.
You can find more details about the mirror area in the RL78 software manual (Section 2.2.1) : https://llvm-gcc-renesas.com/pdf/r01us0015ej0220_rl78.pdf
