Fix build with LLVM 22 debug records API

In LLVM 22, debug variable intrinsics were replaced with
DbgVariableRecord non-instruction debug records. DbgVariableRecord
has no metadata slots, so calling setMetadata() on it fails to
compile. Guard the affected call sites behind an LLVM version
check until the debug info emitter is fully migrated to the new
debug records API.

Author: karolzwolak

IGC/Compiler/Optimizer/OpenCLPasses/PrivateMemory/PrivateMemoryResolution.cpp

@@ -1036,12 +1036,26 @@ bool PrivateMemoryResolution::resolveAllocaInstructions(bool privateOnStack, boo
           unsigned scalarBufferOffset = m_ModAllocaInfo->getBufferOffset(pAI);
           unsigned bufferSize = m_ModAllocaInfo->getBufferStride(pAI);
 
-          // Attach metadata to instruction containing offset of storage
+          // Attach metadata to instruction containing offset of storage.
+          // In LLVM >= 22 debug declares are DbgVariableRecord objects (not Instructions)
+          // and have no metadata slots. The DwarfDebug/DwarfCompileUnit consumers
+          // (buildFpBasedLoc, buildPrivateBaseRegBased) are also not yet migrated to
+          // the new debug-records API and cannot find these declares anyway, so skip
+          // the metadata for now.
+          // FIXME: once DwarfDebug is migrated to DbgVariableRecord, carry StorageOffset
+          // and StorageSize via an alternative mechanism (e.g. DbgVariableRecord side
+          // map or DIExpression extension).
+#if LLVM_VERSION_MAJOR < 22
           auto OffsetMD =
               MDNode::get(builder.getContext(), ConstantAsMetadata::get(builder.getInt32(scalarBufferOffset)));
           DbgDcl->setMetadata("StorageOffset", OffsetMD);
           auto SizeMD = MDNode::get(builder.getContext(), ConstantAsMetadata::get(builder.getInt32(bufferSize)));
           DbgDcl->setMetadata("StorageSize", SizeMD);
+#else
+          (void)scalarBufferOffset;
+          (void)bufferSize;
+          (void)DbgDcl;
+#endif
         }
       }
       // Replace all uses of original alloca with the bitcast
@@ -1335,11 +1349,16 @@ bool PrivateMemoryResolution::resolveAllocaInstructions(bool privateOnStack, boo
     if (modMD->compOpt.OptDisable) {
       auto DbgDcls = IGCLLVM::findDbgDeclareUses(pAI);
       for (auto DbgDcl : DbgDcls) {
-        // Attach metadata to instruction containing offset of storage
+        // Attach metadata to instruction containing offset of storage.
+        // FIXME: for llvm 22 (see above for more context).
+#if LLVM_VERSION_MAJOR < 22
         unsigned int scalarBufferOffset = m_ModAllocaInfo->getBufferOffset(pAI);
         auto OffsetMD =
             MDNode::get(builder.getContext(), ConstantAsMetadata::get(builder.getInt32(scalarBufferOffset)));
         DbgDcl->setMetadata("StorageOffset", OffsetMD);
+#else
+        (void)DbgDcl;
+#endif
       }
     }