Cherry-pick further changes from CTSRD main up to b20a2cbea5a8fbf1f4ec7c9a53e0fe03c96cc052 #263
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resistor
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Nov 3, 2025
resistor
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- [ELF][RISCV] Don't set sizeRel
- [ELF][RISCV] Don't set cheriCapCallRel
- [RISCV] Drop CHERI-RISC-V-specific assembly modifiers and relocations
- [BinaryFormat][RISCV] Mark no-longer used CHERI relocations deprecated
- [BinaryFormat][RISCV] Ditch R_RISCV_CHERI_CAPABILITY_CALL in comment
- [BinaryFormat][RISCV] Delete R_RISCV_CHERI_SIZE
- [ELF][CHERI] Support creating new capability relocations against sections
- [ELF][RISCV] Stop using CSub for capability subtraction
This exists to support __cap_relocs for preemptible symbols, but that was always a bit broken and was replaced long ago even on CHERI-MIPS with proper ELF relocations (though the option not to still exists). CHERI-RISC-V never used this, and CheriBSD does not support it.
This was never on CHERI-RISC-V even when we used .captable, as we passed R_CHERI_CAPABILITY_TABLE_INDEX to ensure the relocation was in .rela.dyn and thus would also use cheriCapRel rather than cheriCapCallRel. Now the normal .got is used instead there isn't even a path that could use this.
LLD is now using a normal GOT so all the captable-related names are a misnomer, instead they should be the same as the normal GOT ones. We can also drop various other gratuitously-different relocations and modifiers whilst here. The idea was to make it possible to support mixing integer and capability mode instructions when it comes to instructions that need relocations, but that comes down to the same problem that R_RISCV_RELAX faces when it comes to .option arch, so we shouldn't be doing something special here that leads to a bunch of unnecessary divergence. As far as I know we don't have any assembly in our software stack that uses these modifiers, it all uses the pseudos that hide this detail.
We can just reuse R_RISCV_JUMP_SLOT when needed.
This has never actually been used (it only appeared to be used in LLD, but never was in practice), nor is it supported by any run-time linker.
…ions This will be needed to initialise .got.plt entries to refer to .plt[0]. The infrastructure is already mostly there, we just need to expose it via the addCapabilityRelocation interface and remove some assumptions.
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This code is currently dead since we emit an all-zeroes PLT header on CHERI-RISC-V, but will soon be used. Fixes: 05652b9 ("[CHERI-RISC-V] Remove CSub")
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