[llvm] MC: Refine ALIGN relocation conditions (PR #150816)

[Fangrui Song via llvm-commits]

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@@ -255,7 +255,8 @@ bool LoongArchAsmBackend::relaxAlign(MCFragment &F, unsigned &Size) {
       MCFixup::create(0, Expr, FirstLiteralRelocationKind + ELF::R_LARCH_ALIGN);
   F.setVarFixups({Fixup});
   F.setLinkerRelaxable();
-  F.getParent()->setLinkerRelaxable();
+  if (!F.getParent()->isLinkerRelaxable())
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MaskRay wrote:

Note: I made minimum changes to keep LoongArch tests passing but I do not intend to apply the ALIGN optimization (first behavior in the description).

Up to a LoongArch contributor to replace `if (!F.getSubtargetInfo()->hasFeature(LoongArch::FeatureRelax))` with 
`if (F.getLayoutOrder() <= Sec->firstLinkerRelaxable())` @SixWeining @MQ-mengqing 

https://github.com/llvm/llvm-project/pull/150816