[llvm] [MC][RISCV][LoongArch] Add AlignFragment size if layout is available and not need insert nops (PR #76552)

[Jinyang He via llvm-commits]

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@@ -47,3 +51,28 @@ G2:
 # RELAX: 0x1C R_RISCV_SUB8 .L1 0x0
 # RELAX: 0x1D R_RISCV_ADD8 G2 0x0
 # RELAX: 0x1D R_RISCV_SUB8 G1 0x0
+
+.dword .L3-.L2
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MQ-mengqing wrote:

So check `shouldInsertExtraNopBytesForCodeAlign` before add `Displacement`. We'll do something like RISCV to handle alignment directive, but now it miss the relax alignment part and `shouldInsertExtraNopBytesForCodeAlign` return false always.

https://github.com/llvm/llvm-project/pull/76552