[clang] [RISCV][FMV] Support target_clones (PR #85786)

[Piyou Chen via cfe-commits]

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@@ -63,9 +63,55 @@ class RISCVABIInfo : public DefaultABIInfo {
                                                CharUnits Field2Off) const;
 
   ABIArgInfo coerceVLSVector(QualType Ty) const;
+
+  using ABIInfo::appendAttributeMangling;
+  void appendAttributeMangling(TargetClonesAttr *Attr, unsigned Index,
+                               raw_ostream &Out) const override;
+  void appendAttributeMangling(StringRef AttrStr,
+                               raw_ostream &Out) const override;
 };
 } // end anonymous namespace
 
+void RISCVABIInfo::appendAttributeMangling(TargetClonesAttr *Attr,
+                                           unsigned Index,
+                                           raw_ostream &Out) const {
+  appendAttributeMangling(Attr->getFeatureStr(Index), Out);
+}
+
+void RISCVABIInfo::appendAttributeMangling(StringRef AttrStr,
+                                           raw_ostream &Out) const {
+  if (AttrStr == "default") {
+    Out << ".default";
+    return;
+  }
+
+  Out << '.';
+
+  SmallVector<StringRef, 8> Attrs;
+  AttrStr.split(Attrs, ";");
+
+  // Drop Priority syntax.
+  StringRef ArchStr;
+  for (auto &Attr : Attrs) {
+    if (Attr.starts_with("arch="))
+      ArchStr = Attr;
+  }
+
+  // Extract features string.s
+  SmallVector<StringRef, 8> Features;
+  ArchStr.consume_front("arch=");
+  ArchStr.split(Features, ",");
+
+  llvm::stable_sort(Features, [](const StringRef LHS, const StringRef RHS) {
+    return LHS.compare(RHS) < 0;
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BeMg wrote:

Oops, I didn't notice it. Drop the lambda now. 

https://github.com/llvm/llvm-project/pull/85786