[MLIR][GPU-LLVM] Define -convert-gpu-to-llvm-spv pass (#90972)

Define pass for GPU to LLVM conversion for SPIR-V backend tool ingest.

Supported operations:

- `gpu.block_id`
- `gpu.global_id`
- `gpu.block_dim`
- `gpu.thread_id`
- `gpu.grid_dim`
- `gpu.barrier`
- `gpu.shuffle`

---------

Signed-off-by: Victor Perez <[email protected]>

Author: victor-eds

mlir/include/mlir/Conversion/GPUToLLVMSPV/GPUToLLVMSPVPass.h

@@ -0,0 +1,27 @@
+//===- GPUToLLVMSPVPass.h - Convert GPU kernel to LLVM operations *- C++ -*-==//
+//
+// Part of the LLVM 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
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef MLIR_CONVERSION_GPUTOLLVMSPV_GPUTOLLVMSPVPASS_H_
+#define MLIR_CONVERSION_GPUTOLLVMSPV_GPUTOLLVMSPVPASS_H_
+
+#include <memory>
+
+namespace mlir {
+class DialectRegistry;
+class LLVMTypeConverter;
+class RewritePatternSet;
+class Pass;
+
+#define GEN_PASS_DECL_CONVERTGPUOPSTOLLVMSPVOPS
+#include "mlir/Conversion/Passes.h.inc"
+
+void populateGpuToLLVMSPVConversionPatterns(LLVMTypeConverter &converter,
+                                            RewritePatternSet &patterns);
+} // namespace mlir
+
+#endif // MLIR_CONVERSION_GPUTOLLVMSPV_GPUTOLLVMSPVPASS_H_

mlir/include/mlir/Conversion/Passes.h

@@ -34,6 +34,7 @@
 #include "mlir/Conversion/FuncToLLVM/ConvertFuncToLLVMPass.h"
 #include "mlir/Conversion/FuncToSPIRV/FuncToSPIRVPass.h"
 #include "mlir/Conversion/GPUCommon/GPUCommonPass.h"
+#include "mlir/Conversion/GPUToLLVMSPV/GPUToLLVMSPVPass.h"
 #include "mlir/Conversion/GPUToNVVM/GPUToNVVMPass.h"
 #include "mlir/Conversion/GPUToROCDL/GPUToROCDLPass.h"
 #include "mlir/Conversion/GPUToSPIRV/GPUToSPIRVPass.h"

mlir/include/mlir/Conversion/Passes.td

@@ -508,6 +508,24 @@ def LowerHostCodeToLLVMPass : Pass<"lower-host-to-llvm", "ModuleOp"> {
   let dependentDialects = ["LLVM::LLVMDialect"];
 }
 
+//===----------------------------------------------------------------------===//
+// GPUToLLVMSPV
+//===----------------------------------------------------------------------===//
+
+def ConvertGpuOpsToLLVMSPVOps : Pass<"convert-gpu-to-llvm-spv", "gpu::GPUModuleOp"> {
+  let summary =
+    "Generate LLVM operations to be ingested by a SPIR-V backend for gpu operations";
+  let dependentDialects = [
+    "LLVM::LLVMDialect",
+    "spirv::SPIRVDialect",
+  ];
+  let options = [
+    Option<"indexBitwidth", "index-bitwidth", "unsigned",
+           /*default=kDeriveIndexBitwidthFromDataLayout*/"0",
+           "Bitwidth of the index type, 0 to use size of machine word">,
+  ];
+}
+
 //===----------------------------------------------------------------------===//
 // GPUToNVVM
 //===----------------------------------------------------------------------===//

mlir/lib/Conversion/CMakeLists.txt

@@ -23,6 +23,7 @@ add_subdirectory(FuncToEmitC)
 add_subdirectory(FuncToLLVM)
 add_subdirectory(FuncToSPIRV)
 add_subdirectory(GPUCommon)
+add_subdirectory(GPUToLLVMSPV)
 add_subdirectory(GPUToNVVM)
 add_subdirectory(GPUToROCDL)
 add_subdirectory(GPUToSPIRV)

mlir/lib/Conversion/GPUToLLVMSPV/CMakeLists.txt

@@ -0,0 +1,12 @@
+add_mlir_conversion_library(MLIRGPUToLLVMSPV
+  GPUToLLVMSPV.cpp
+
+  DEPENDS
+  MLIRConversionPassIncGen
+
+  LINK_LIBS PUBLIC
+  MLIRGPUDialect
+  MLIRLLVMCommonConversion
+  MLIRLLVMDialect
+  MLIRSPIRVDialect
+)