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

[Luohao Wang]

================
@@ -80,10 +82,13 @@ std::tuple<Value, Value> AllocationOpLLVMLowering::allocateBufferManuallyAlign(
         << " to integer address space "
            "failed. Consider adding memory space conversions.";
   }
-  LLVM::LLVMFuncOp allocFuncOp = getNotalignedAllocFn(
+  FailureOr<LLVM::LLVMFuncOp> allocFuncOp = getNotalignedAllocFn(
       getTypeConverter(), op->getParentWithTrait<OpTrait::SymbolTable>(),
       getIndexType());
-  auto results = rewriter.create<LLVM::CallOp>(loc, allocFuncOp, sizeBytes);
+  if (failed(allocFuncOp))
+    return std::make_tuple(Value(), Value());
----------------
Luohaothu wrote:

The returned pair of value is populated and finally verified here: [AllocLikeConvertion.cpp](https://github.com/llvm/llvm-project/blob/18335f4800ae5491a11e74a574969d716acddce7/mlir/lib/Conversion/MemRefToLLVM/AllocLikeConversion.cpp#L181-L187)
```cpp
  // Allocate the underlying buffer.
  auto [allocatedPtr, alignedPtr] =
      this->allocateBuffer(rewriter, loc, size, op);

  if (!allocatedPtr || !alignedPtr)
    return rewriter.notifyMatchFailure(loc,
                                       "underlying buffer allocation failed");
```
Here empty value is assigned as the invalid state and properly handled. I prefer to leave it as is, and a separate PR might be more appropriate to modernize the error handling style if we do have a preference.

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