[Mlir-commits] [mlir] [MLIR][XeVM] Add XeVM to LLVMIR translation. (PR #150696)

[Adam Siemieniuk]

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@@ -0,0 +1,108 @@
+//===-- XeVMToLLVMIRTranslation.cpp - Translate XeVM to LLVM IR -*- C++ -*-===//
+//
+// This file is licensed 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 translation between the MLIR XeVM dialect and
+// LLVM IR.
+//
+//===----------------------------------------------------------------------===//
+
+#include "mlir/Target/LLVMIR/Dialect/XeVM/XeVMToLLVMIRTranslation.h"
+#include "mlir/Dialect/LLVMIR/XeVMDialect.h"
+#include "mlir/IR/BuiltinAttributes.h"
+#include "mlir/IR/Operation.h"
+#include "mlir/Target/LLVMIR/ModuleTranslation.h"
+
+#include "llvm/ADT/TypeSwitch.h"
+#include "llvm/IR/Constants.h"
+#include "llvm/IR/LLVMContext.h"
+#include "llvm/IR/Metadata.h"
+
+#include "llvm/IR/ConstantRange.h"
+#include "llvm/IR/IRBuilder.h"
+#include "llvm/Support/raw_ostream.h"
+
+using namespace mlir;
+using namespace mlir::LLVM;
+
+namespace {
+/// Implementation of the dialect interface that converts operations belonging
+/// to the XeVM dialect to LLVM IR.
+class XeVMDialectLLVMIRTranslationInterface
+    : public LLVMTranslationDialectInterface {
+public:
+  using LLVMTranslationDialectInterface::LLVMTranslationDialectInterface;
+
+  /// Attaches module-level metadata for functions marked as kernels.
+  LogicalResult
+  amendOperation(Operation *op, ArrayRef<llvm::Instruction *> instructions,
+                 NamedAttribute attribute,
+                 LLVM::ModuleTranslation &moduleTranslation) const final {
+    StringRef attrName = attribute.getName().getValue();
+    if (attrName == mlir::xevm::XeVMDialect::getCacheControlsAttrName()) {
+      auto cacheControlsArray = dyn_cast<ArrayAttr>(attribute.getValue());
+      if (cacheControlsArray.size() != 2) {
+        return op->emitOpError(
+            "Expected both L1 and L3 cache control attributes!");
+      }
+      if (instructions.size() != 1) {
+        return op->emitOpError("Expecting a single instruction");
+      }
+      return handleDecorationCacheControl(instructions.front(),
+                                          cacheControlsArray.getValue());
+    }
+    auto func = dyn_cast<LLVM::LLVMFuncOp>(op);
+    if (!func)
+      return failure();
+
+    return success();
+  }
+
+private:
+  template <typename IntTy>
+  static llvm::Metadata *getConstantIntMD(llvm::Type *type, IntTy val) {
+    return llvm::ConstantAsMetadata::get(llvm::ConstantInt::get(type, val));
+  }
+
+  static LogicalResult handleDecorationCacheControl(llvm::Instruction *inst,
+                                                    ArrayRef<Attribute> attrs) {
+    SmallVector<llvm::Metadata *> decorations;
+    llvm::LLVMContext &ctx = inst->getContext();
+    llvm::Type *i32Ty = llvm::IntegerType::getInt32Ty(ctx);
+    llvm::transform(
+        attrs, std::back_inserter(decorations),
+        [&ctx, i32Ty](Attribute attr) -> llvm::Metadata * {
+          auto valuesArray = dyn_cast<ArrayAttr>(attr).getValue();
+          std::array<llvm::Metadata *, 4> metadata;
+          llvm::transform(
+              valuesArray, metadata.begin(), [i32Ty](Attribute valueAttr) {
+                return llvm::ConstantAsMetadata::get(llvm::ConstantInt::get(
+                    i32Ty, cast<IntegerAttr>(valueAttr).getValue()));
+              });
+          return llvm::MDNode::get(ctx, metadata);
+        });
+    constexpr llvm::StringLiteral decorationCacheControlMDName =
+        "spirv.DecorationCacheControlINTEL";
+    inst->setMetadata(decorationCacheControlMDName,
+                      llvm::MDNode::get(ctx, decorations));
+    return success();
+  }
+};
+} // namespace
+
+void ::mlir::registerXeVMDialectTranslation(::mlir::DialectRegistry &registry) {
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adam-smnk wrote:

nit: doesn't need leading `::`

https://github.com/llvm/llvm-project/pull/150696