[llvm] [llvm] Support multiple save/restore points in mir (PR #119357)

[Elizaveta Noskova via llvm-commits]

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@@ -1077,6 +1075,54 @@ bool MIRParserImpl::initializeConstantPool(PerFunctionMIParsingState &PFS,
   return false;
 }
 
+// Return true if basic block was incorrectly specified in MIR
+bool MIRParserImpl::initializeSaveRestorePoints(
+    PerFunctionMIParsingState &PFS, const yaml::SaveRestorePoints &YamlSRPoints,
+    bool IsSavePoints) {
+  SMDiagnostic Error;
+  MachineBasicBlock *MBB = nullptr;
+  llvm::SaveRestorePoints SRPoints;
+  std::vector<Register> Registers;
+
+  if (std::holds_alternative<std::vector<yaml::SaveRestorePointEntry>>(
+          YamlSRPoints)) {
+    const auto &VectorRepr =
+        std::get<std::vector<yaml::SaveRestorePointEntry>>(YamlSRPoints);
+    if (VectorRepr.empty())
+      return false;
+    for (const auto &Entry : VectorRepr) {
+      const auto &MBBSource = Entry.Point;
+      if (parseMBBReference(PFS, MBB, MBBSource.Value))
+        return true;
+
+      Registers.clear();
+      for (auto &RegStr : Entry.Registers) {
+        Register Reg;
+        if (parseNamedRegisterReference(PFS, Reg, RegStr.Value, Error))
+          return error(Error, RegStr.SourceRange);
+        Registers.push_back(Reg);
+      }
+      SRPoints.insert(std::make_pair(MBB, Registers));
+    }
+  } else {
+    yaml::StringValue StringRepr = std::get<yaml::StringValue>(YamlSRPoints);
+    if (StringRepr.Value.empty())
+      return false;
+    if (parseMBBReference(PFS, MBB, StringRepr))
+      return true;
+    SRPoints.insert(std::make_pair(MBB, Registers));
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enoskova-sc wrote:

addressed

https://github.com/llvm/llvm-project/pull/119357