Add in-dialect lowering of gpu.all_reduce.

[merge_guards_bot]

Unit tests: pass. 61127 tests passed, 0 failed and 728 were skipped.

clang-tidy: fail. Please fix clang-tidy findings.

clang-format: pass.

Build artifacts: diff.json, clang-tidy.txt, clang-format.patch, CMakeCache.txt, console-log.txt, test-results.xml

mlir/lib/Conversion/GPUToCUDA/ConvertKernelFuncToCubin.cpp

 //===- ConvertKernelFuncToCubin.cpp - MLIR GPU lowering passes ------------===//
 //
 // Part of the MLIR Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 //
 // This file implements a pass to convert gpu kernel functions into a
 // corresponding binary blob that can be executed on a CUDA GPU. Currently
 // only translates the function itself but no dependencies.
 //
 //===----------------------------------------------------------------------===//
 
 #include "mlir/Conversion/GPUToCUDA/GPUToCUDAPass.h"
 
 #include "mlir/Dialect/GPU/GPUDialect.h"
 #include "mlir/IR/Attributes.h"
 #include "mlir/IR/Builders.h"
 #include "mlir/IR/Function.h"
 #include "mlir/IR/Module.h"
 #include "mlir/Pass/Pass.h"
 #include "mlir/Pass/PassRegistry.h"
std::string GpuKernelToCubinPass::translateModuleToPtx(
   {
     llvm::raw_string_ostream stream(ptx);
     llvm::buffer_ostream pstream(stream);
     llvm::legacy::PassManager codegen_passes;
     target_machine.addPassesToEmitFile(codegen_passes, pstream, nullptr,
                                        llvm::CGFT_AssemblyFile);
     codegen_passes.run(module);
   }
-
+  llvm::errs() << ptx;
   return ptx;
 }
 
 OwnedCubin
 GpuKernelToCubinPass::compilePtxToCubinForTesting(const std::string &ptx,
                                                   Location, StringRef) {
   const char data[] = "CUBIN";
   return std::make_unique<std::vector<char>>(data, data + sizeof(data) - 1);