Mach-O AArch64 relocation addend improvements #581
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For PC relative relocations on some architectures, the implicit addend does not include the offset required due to the PC being different from the place of the relocation. Previously we always used an offset of 4, since this is commonly required by x86-64. However, this is not correct for AArch64 or for some x8-64 relocations, and probably not correct for other architectures either. For example, the ARM offset may vary depending on the instruction used. For now, disable this handling for all non x86 targets. This fixes AArch64. Support for other architectures is left as a TODO.
- fix SectionHeader::nreloc to include additional ARM64_RELOC_ADDEND relocations - switch order of ARM64_RELOC_ADDEND and its paired relocation - emit ARM64_RELOC_ADDEND for more relocation types
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Jun 15, 2024
Mach-O AArch64 relocation addend improvements
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macho: fix PC relative relocation offset for AArch64
For PC relative relocations on some architectures, the implicit addend does not include the offset required due to the PC being different from the place of the relocation.
Previously we always used an offset of 4, since this is commonly required by x86-64. However, this is not correct for AArch64 or for some x8-64 relocations, and probably not correct for other architectures either. For example, the ARM offset may vary depending on the instruction used.
For now, disable this handling for all non x86 targets. This fixes AArch64. Support for other architectures is left as a TODO.
write/macho: fix ARM64_RELOC_ADDEND handling
Closes #580
read/macho: handle ARM64_RELOC_ADDEND
Closes #466
cc @nathanwhit If you're still working in this area, can you review and ensure that your changes from #465 still work? I'll look into adding some tests for this too.