[llvm] [feature][riscv] handle target address calculation in llvm-objdump disassembly for riscv (PR #144620)

[Arjun Patel via llvm-commits]

arjunUpatel wrote:

> Regarding the testing, is it really necessary to use a cross-project-test for these, rather than an llvm-mc or similar directly?

The object file generated by `llvm-mc` does not seem to be able to encode instructions in the floating point and zcb extensions properly. When the output is disassembled with `llvm-objdump`, we get `<unknown>` for these instructions instead of address resolution as seen here:
```
      2e: 00102427     	<unknown>
      32: 00110097     	auipc	ra, 0x110
      36: fda080e7     	jalr	-0x26(ra) <func>
      3a: 640d         	lui	s0, 0x3
      3c: 8800         	<unknown>
```
Assembled with `llvm-mc -triple=riscv64 -mattr=+f,+c,+zcb riscv64-ar-coverage.s -o riscv64-ar-coverage.s`. Could I be missing some options that might be causing this?

> Does the testing work if you instead rely on relocations to evaluate branch etc targets?

I'm not sure I understand what you mean by this. Can you please elaborate?


https://github.com/llvm/llvm-project/pull/144620