[Mlir-commits] [mlir] [MLIR][GPU-LLVM] Define `-convert-gpu-to-llvm-spv` pass (PR #90972)

[Mehdi Amini]

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@@ -0,0 +1,329 @@
+//===- GPUToLLVMSPV.cpp - Convert GPU operations to LLVM dialect ----------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#include "mlir/Conversion/GPUToLLVMSPV/GPUToLLVMSPVPass.h"
+
+#include "mlir/Conversion/LLVMCommon/ConversionTarget.h"
+#include "mlir/Conversion/LLVMCommon/LoweringOptions.h"
+#include "mlir/Conversion/LLVMCommon/Pattern.h"
+#include "mlir/Conversion/LLVMCommon/TypeConverter.h"
+#include "mlir/Dialect/GPU/IR/GPUDialect.h"
+#include "mlir/Dialect/LLVMIR/LLVMAttrs.h"
+#include "mlir/Dialect/LLVMIR/LLVMDialect.h"
+#include "mlir/Dialect/LLVMIR/LLVMTypes.h"
+#include "mlir/Dialect/SPIRV/IR/SPIRVDialect.h"
+#include "mlir/Dialect/SPIRV/IR/TargetAndABI.h"
+#include "mlir/IR/BuiltinTypes.h"
+#include "mlir/IR/Matchers.h"
+#include "mlir/IR/PatternMatch.h"
+#include "mlir/IR/SymbolTable.h"
+#include "mlir/Pass/Pass.h"
+#include "mlir/Support/LLVM.h"
+#include "mlir/Transforms/DialectConversion.h"
+
+#include "llvm/ADT/TypeSwitch.h"
+#include "llvm/Support/FormatVariadic.h"
+
+using namespace mlir;
+
+namespace mlir {
+#define GEN_PASS_DEF_CONVERTGPUOPSTOLLVMSPVOPS
+#include "mlir/Conversion/Passes.h.inc"
+} // namespace mlir
+
+//===----------------------------------------------------------------------===//
+// Helper Functions
+//===----------------------------------------------------------------------===//
+
+static LLVM::LLVMFuncOp lookupOrCreateSPIRVFn(Operation *symbolTable,
+                                              StringRef name,
+                                              ArrayRef<Type> paramTypes,
+                                              Type resultType) {
+  auto func = dyn_cast_or_null<LLVM::LLVMFuncOp>(
+      SymbolTable::lookupSymbolIn(symbolTable, name));
+  if (!func) {
+    OpBuilder b(symbolTable->getRegion(0));
+    func = b.create<LLVM::LLVMFuncOp>(
+        symbolTable->getLoc(), name,
+        LLVM::LLVMFunctionType::get(resultType, paramTypes));
+    func.setCConv(LLVM::cconv::CConv::SPIR_FUNC);
+  }
+  return func;
+}
+
+static LLVM::CallOp createSPIRVBuiltinCall(Location loc,
+                                           ConversionPatternRewriter &rewriter,
+                                           LLVM::LLVMFuncOp func,
+                                           ValueRange args) {
+  auto call = rewriter.create<LLVM::CallOp>(loc, func, args);
+  call.setCConv(func.getCConv());
+  return call;
+}
+
+namespace {
+//===----------------------------------------------------------------------===//
+// Barriers
+//===----------------------------------------------------------------------===//
+
+/// Replace `gpu.barrier` with an `llvm.call` to `barrier` with
+/// `CLK_LOCAL_MEM_FENCE` argument, indicating work-group memory scope:
+/// ```
+/// // gpu.barrier
+/// %c1 = llvm.mlir.constant(1: i32) : i32
+/// llvm.call spir_funccc @_Z7barrierj(%c1) : (i32) -> ()
+/// ```
+struct GPUBarrierConversion final : ConvertOpToLLVMPattern<gpu::BarrierOp> {
----------------
joker-eph wrote:

I'm not sure where would the LLVM coding standard says anything about defining methods outside of the class?

I see about anonymous namespace this:

> Because of this, we have a simple guideline: make anonymous namespaces as small as possible, and only use them for class declarations.

But this makes no statement about not keeping methods inline as far as I can tell.


https://github.com/llvm/llvm-project/pull/90972