[llvm] [llvm-exegesis] Debug generated disassembly (PR #142540)

[Aiden Grossman via llvm-commits]

boomanaiden154 wrote:

> This would be a very welcome debug feature for me. I agree that this can be achieved in the way you described it, but it would be so much more efficient for me if I can flip a switch and don't need to do this all manually. Analysing the snippets is really important, i.e. analysing them to see if they truly test what they want to test is important and time consuming, and anything that helps is welcome.

The snippet (not repeated) is already shown in the benchmark key:
```
key:
  instructions:
    - 'CMP64rr RSI RSI'
    - 'ADC64ri32_ND RSI RDI i_0x1'
```

I don't see how this patch will provide significant benefit over that, other than maybe printing everything in a more familiar format.

> I agree we don't want hard-code paths, so we want to remove /usr/bin/objdump, and we want to change that to llvm-objdump. That is already used in some test cases, so that is not a new dependency,

I don't see how this is preferrable to a `MCInstPrinter`.

https://github.com/llvm/llvm-project/pull/142540