[llvm] [NVPTX] Load/Store/Fence syncscope support (PR #106101)

[via llvm-commits]

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@@ -4064,3 +4158,43 @@ unsigned NVPTXDAGToDAGISel::GetConvertOpcode(MVT DestTy, MVT SrcTy,
     }
   }
 }
+
+bool NVPTXDAGToDAGISel::tryFence(SDNode *N) {
+  SDLoc DL(N);
+  assert(N->getOpcode() == ISD::ATOMIC_FENCE);
+  unsigned int FenceOp =
+      getFenceOp(NVPTX::Ordering(N->getConstantOperandVal(1)),
+                 Scopes[N->getConstantOperandVal(2)], Subtarget);
+  SDValue Chain = N->getOperand(0);
+  SDNode *FenceNode = CurDAG->getMachineNode(FenceOp, DL, MVT::Other, Chain);
+  ReplaceNode(N, FenceNode);
+  return true;
+}
+
+NVPTXScopes::NVPTXScopes(LLVMContext &C) : CTX(&C) {
+  Scopes[C.getOrInsertSyncScopeID("singlethread")] = NVPTX::Scope::Thread;
+  Scopes[C.getOrInsertSyncScopeID("")] = NVPTX::Scope::System;
+  Scopes[C.getOrInsertSyncScopeID("block")] = NVPTX::Scope::Block;
+  Scopes[C.getOrInsertSyncScopeID("cluster")] = NVPTX::Scope::Cluster;
+  Scopes[C.getOrInsertSyncScopeID("device")] = NVPTX::Scope::Device;
+}
+
+NVPTX::Scope NVPTXScopes::operator[](SyncScope::ID ID) const {
+  if (Scopes.empty())
+    report_fatal_error("NVPTX Scopes must be initialized before calling "
+                       "NVPTXScopes::operator[]");
+
+  auto S = Scopes.find(ID);
+  if (S == Scopes.end()) {
+    SmallVector<StringRef, 8> ScopeNames;
+    assert(CTX != nullptr && "CTX is nullptr");
+    CTX->getSyncScopeNames(ScopeNames);
+    StringRef Unknown{"unknown"};
+    auto Name = ID < ScopeNames.size() ? ScopeNames[ID] : Unknown;
+    report_fatal_error(
+        formatv("Could not find scope ID={} with name \"{}\".", int(ID), Name));
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gonzalobg wrote:

The IDs in the LLVM IR module are dynamic, and change depending on which order `syncscopes` appear in the module, so the numbers aren't really very useful in the error messages...

https://github.com/llvm/llvm-project/pull/106101