[llvm-objcopy] Add change-section-lma *+/-offset (#95431) llvm-objcopy did not support change-section-lma argument. This patch adds support for a use case of change-section-lma, that is shifting load address of all sections by the same offset. This seems to be the only practical use case of change-section-lma, found in other software such as Zephyr RTOS's build system. This is an option that could possibly be supported in some other than ELF formats, however this change only implements it for ELF. When used with other formats an error message is raised. In comparison, the behavior of GNU objcopy is inconsistent. For some ELF files it behaves the same as described above. For others, it copies the file without modifying the p_paddr fields when it would be expected. In some experiments it modifies arbitrary fields in section or program headers. It is unclear what exactly determines this. The executable file generated by yaml2obj in this test is not parsable by GNU objcopy. With Machine set to EM_AARCH64, the file can be parsed and the first test in the test file completes with 0 exit code. However, the result is rather arbitrary. AArch64 GNU objcopy subtracts 0x1000 from p_filesz and p_memsz of the first LOAD section and 0x1000 from p_offset of the second LOAD section. It does not look meaningful.
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