<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/100290>100290</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [lld][RISC-V] `mv rd rd` used in global symbol address calculation could be eliminated.
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            lld
      </td>
    </tr>

    <tr>
      <th>Assignees</th>
      <td>
      </td>
    </tr>

    <tr>
      <th>Reporter</th>
      <td>
          wan-yuqi
      </td>
    </tr>
</table>

<pre>
    When compiling a pragma which uses a global symbol and targets `riscv*`, it will generate a sequence instructions for calculating address: 
```
foo:
 lui  a0, %hi(Var)
  addi a0, a0, %lo(Var)
```
When the address of `Var` is aligned to 0x1000, such as 0x20000, calculation instructions will be:
```
foo:
  lui  a0, 20
  mv   a0, a0   # pseudo instruction of `addi a0, a0, 0`
```
I think `mv a0, a0` could be eliminated by linker relaxation (which the target and source registers are the same and R_RISCV_LO12_I is `ADDI`) to reduce unnecessary instructions. But it' s not mentioned in riscv-elf-psabi-doc. Is there any negative impact?

</pre>
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