[lld] [llvm] Reapply "[RISCV] Support RISCV Atomics ABI attributes (#84597)" (PR #90266)

[Fangrui Song via llvm-commits]

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@@ -1134,6 +1186,17 @@ mergeAttributesSection(const SmallVector<InputSectionBase *, 0> &sections) {
       case RISCVAttrs::PRIV_SPEC_MINOR:
       case RISCVAttrs::PRIV_SPEC_REVISION:
         break;
+
+      case llvm::RISCVAttrs::AttrType::ATOMIC_ABI:
+        if (auto i = parser.getAttributeValue(tag.attr)) {
+          auto r = merged.intAttr.try_emplace(tag.attr, *i);
+          if (r.second) {
+            firstAtomicAbi = sec;
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MaskRay wrote:

no braces for one-line single statements

see other comments in #84597

https://github.com/llvm/llvm-project/pull/90266