[llvm] [llvm-objdump] Support --mcpu=help/--mattr=help without -d (PR #165661)

[James Henderson via llvm-commits]

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@@ -0,0 +1,25 @@
+# RUN: yaml2obj %s -o %t
+# REQUIRES: mips-registered-target,x86-registered-target
----------------
jh7370 wrote:

```suggestion
# REQUIRES: mips-registered-target
```

You don't need target support for the input object when you are specifying --triple, you just need it for the specified value.

I'd strongly consider using RISC-V rather than MIPS. I couldn't see a build bot at https://lab.llvm.org/buildbot/#/console which lists MIPS in its name, which might mean this test would never run under a build bot, whereas there are at least 3 bots that target RISC-V.

Better yet, it might be worth trying with Aarch64, as that's targeted by several more, although I don't know if it has the same issue as the Arm target.

Alternatively, invert things so that you use x86_64 in the --triple value and use MIPS as your YAML's machine value.

https://github.com/llvm/llvm-project/pull/165661