[clang] [MLIR] SPIRV Target Attribute (PR #69949)

[Lei Zhang via cfe-commits]

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@@ -0,0 +1,117 @@
+//===- Target.cpp - MLIR SPIRV target compilation ---------------*- 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
+//
+//===----------------------------------------------------------------------===//
+//
+// This files defines SPIRV target related functions including registration
+// calls for the `#spirv.target` compilation attribute.
+//
+//===----------------------------------------------------------------------===//
+
+#include "mlir/Target/SPIRV/Target.h"
+
+#include "mlir/Dialect/GPU/IR/GPUDialect.h"
+#include "mlir/Dialect/SPIRV/IR/SPIRVAttributes.h"
+#include "mlir/Dialect/SPIRV/IR/SPIRVDialect.h"
+#include "mlir/Dialect/SPIRV/IR/SPIRVOps.h"
+#include "mlir/Target/LLVMIR/Dialect/GPU/GPUToLLVMIRTranslation.h"
+#include "mlir/Target/LLVMIR/Dialect/LLVMIR/LLVMToLLVMIRTranslation.h"
+#include "mlir/Target/LLVMIR/Export.h"
+#include "mlir/Target/SPIRV/Serialization.h"
+
+#include "llvm/Support/FileSystem.h"
+#include "llvm/Support/FileUtilities.h"
+#include "llvm/Support/FormatVariadic.h"
+#include "llvm/Support/MemoryBuffer.h"
+#include "llvm/Support/Path.h"
+#include "llvm/Support/Process.h"
+#include "llvm/Support/Program.h"
+#include "llvm/Support/TargetSelect.h"
+
+#include <cstdlib>
+#include <cstring>
+
+using namespace mlir;
+using namespace mlir::spirv;
+
+namespace {
+// Implementation of the `TargetAttrInterface` model.
+class SPIRVTargetAttrImpl
+    : public gpu::TargetAttrInterface::FallbackModel<SPIRVTargetAttrImpl> {
+public:
+  std::optional<SmallVector<char, 0>>
+  serializeToObject(Attribute attribute, Operation *module,
+                    const gpu::TargetOptions &options) const;
+
+  Attribute createObject(Attribute attribute,
+                         const SmallVector<char, 0> &object,
+                         const gpu::TargetOptions &options) const;
+};
+} // namespace
+
+// Register the SPIRV dialect, the SPIRV translation & the target interface.
+void mlir::spirv::registerSPIRVTargetInterfaceExternalModels(
+    DialectRegistry &registry) {
+  registry.addExtension(+[](MLIRContext *ctx, spirv::SPIRVDialect *dialect) {
+    spirv::SPIRVTargetAttr::attachInterface<SPIRVTargetAttrImpl>(*ctx);
+  });
+}
+
+void mlir::spirv::registerSPIRVTargetInterfaceExternalModels(
+    MLIRContext &context) {
+  DialectRegistry registry;
+  registerSPIRVTargetInterfaceExternalModels(registry);
+  context.appendDialectRegistry(registry);
+}
+
+// Reuse from existing serializer
+std::optional<SmallVector<char, 0>> SPIRVTargetAttrImpl::serializeToObject(
+    Attribute attribute, Operation *module,
+    const gpu::TargetOptions &options) const {
+  assert(module && "The module must be non null.");
+  if (!module)
+    return std::nullopt;
+  if (!mlir::isa<gpu::GPUModuleOp>(module)) {
+    module->emitError("Module must be a GPU module.");
+    return std::nullopt;
+  }
+  auto gpuMod = dyn_cast<gpu::GPUModuleOp>(module);
+  auto spvMods = gpuMod.getOps<spirv::ModuleOp>();
+  // Empty spirv::ModuleOp
----------------
antiagainst wrote:

The comment here does not provide additional value; we should remove it or expand it to be more clear.

https://github.com/llvm/llvm-project/pull/69949