[Mlir-commits] [mlir] [mlir] Fix conflict of user defined reserved functions with internal prototypes (PR #123378)

[Luohao Wang]

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@@ -48,53 +48,74 @@ static constexpr llvm::StringRef kMemRefCopy = "memrefCopy";
 LLVM::LLVMFuncOp mlir::LLVM::lookupOrCreateFn(Operation *moduleOp,
                                               StringRef name,
                                               ArrayRef<Type> paramTypes,
-                                              Type resultType, bool isVarArg) {
+                                              Type resultType, bool isVarArg,
+                                              bool isReserved) {
   assert(moduleOp->hasTrait<OpTrait::SymbolTable>() &&
          "expected SymbolTable operation");
   auto func = llvm::dyn_cast_or_null<LLVM::LLVMFuncOp>(
       SymbolTable::lookupSymbolIn(moduleOp, name));
-  if (func)
+  auto funcT = LLVMFunctionType::get(resultType, paramTypes, isVarArg);
+  // Assert the signature of the found function is same as expected
+  if (func) {
+    if (funcT != func.getFunctionType()) {
+      if (isReserved) {
+        func.emitError("redefinition of reserved function '" + name +
+                       "' of different type ")
+            .append(func.getFunctionType())
+            .append(" is prohibited");
+        exit(0);
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Luohaothu wrote:

Thanks for the comment. I've wrapped the return value inside a `FailureOr` to propagate the error and add verifiers at the call site to trigger a pass failure.

https://github.com/llvm/llvm-project/pull/123378