ConvertVectorToAIEVec.cpp

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//===-ConvertVectorToAIEVec.cpp - Lower Vector to AIE vector ----*- C++ -*-===//
//
// Copyright (C) 2022 Xilinx, Inc.
// Copyright (C) 2022-2025 Advanced Micro Devices, Inc.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
// This is the implementation of the lowering pass from standard Vector
// dialect to AIEVec, compatible with the AIE vector architecture.
//===----------------------------------------------------------------------===//
 
#include "aie/Dialect/AIEVec/Pipelines/Passes.h"
 
#include "mlir/Dialect/Vector/Transforms/VectorTransforms.h"
#include "mlir/IR/PatternMatch.h"
#include "mlir/IR/TypeUtilities.h"
#include "mlir/Pass/PassManager.h"
#include "mlir/Transforms/GreedyPatternRewriteDriver.h"
#include "mlir/Transforms/Passes.h"
 
namespace xilinx::aievec {
#define GEN_PASS_DEF_LOWERVECTORTOAIEVEC
#define GEN_PASS_DEF_CANONICALIZEFORAIEVEC
#define GEN_PASS_DEF_REDUNDANTLOADSTOREOPTIMIZATION
#define GEN_PASS_DEF_AIEVECTRANSFORMATION
#define GEN_PASS_DEF_AIEVECCONVOPTRANSFORMATION
 
#include "aie/Dialect/AIEVec/Transforms/Passes.h.inc"
} // namespace xilinx::aievec
 
using namespace mlir;
using namespace arith;
using namespace vector;
using namespace xilinx;
using namespace xilinx::aievec;
 
#define DEBUG_TYPE "vector-to-aievec-conversion"
 
//===----------------------------------------------------------------------===//
// Rewrite patterns
//===----------------------------------------------------------------------===//
 
template <typename OpTy>
struct SetInboundsToReadStoreOpPattern : public RewritePattern {
  SetInboundsToReadStoreOpPattern(MLIRContext *context)
      : RewritePattern(OpTy::getOperationName(), /*benefit=*/1, context) {}
 
  LogicalResult matchAndRewrite(Operation *op,
                                PatternRewriter &rewriter) const override {
    OpTy writeOrReadOp = cast<OpTy>(op);
 
    // TODO: We are currently setting all `vector.transfer_read` and
    // TODO: `vector.transfer_write` as "in bounds". We need to add
    // TODO: an analysis to verify that this is true before doing so.
    auto inBounds =
        writeOrReadOp.getInBounds().template getAsValueRange<BoolAttr>();
    if (std::all_of(inBounds.begin(), inBounds.end(),
                    [](bool v) { return v; }) ||
        writeOrReadOp.getTransferRank() == 0)
      return failure();
 
    SmallVector<bool, 4> bools(writeOrReadOp.getTransferRank(), true);
    auto inBoundsAttr = rewriter.getBoolArrayAttr(bools);
    rewriter.modifyOpInPlace(writeOrReadOp, [&]() {
      writeOrReadOp->setAttr(writeOrReadOp.getInBoundsAttrName(), inBoundsAttr);
    });
    return success();
  }
};
 
using SetInboundsToReadOp = SetInboundsToReadStoreOpPattern<TransferReadOp>;
using SetInboundsToWriteOp = SetInboundsToReadStoreOpPattern<TransferWriteOp>;
 
//===----------------------------------------------------------------------===//
// Lowering passes
//===----------------------------------------------------------------------===//
 
struct RedundantLoadStoreOptimizationPass
    : public PassWrapper<RedundantLoadStoreOptimizationPass, OperationPass<>> {
 
  void runOnOperation() override {
    auto *op = getOperation();
    MLIRContext *context = &getContext();
    RewritePatternSet patterns(context);
 
    patterns.add<SetInboundsToReadOp, SetInboundsToWriteOp>(
        patterns.getContext());
 
    (void)applyPatternsGreedily(op, std::move(patterns));
    IRRewriter rewriter(&getContext());
    vector::transferOpflowOpt(rewriter, op);
  }
};
 
static std::unique_ptr<::mlir::Pass>
createRedundantLoadStoreOptimizationPass() {
  return std::make_unique<RedundantLoadStoreOptimizationPass>();
}
 
//===---------------------------------------------------------------------------
// Pipeline implementations
//===---------------------------------------------------------------------------
void xilinx::aievec::buildConvertVectorToAIEVec(
    OpPassManager &pm, const ConvertVectorToAIEVecOptions &options) {
 
  // Pre-conversion passes.
  pm.addPass(createCanonicalizerPass());
  pm.addPass(createRedundantLoadStoreOptimizationPass());
 
  //============================================================================
  // Vector canonicalization for AIEVec: Vector to Vector conversion.
  //============================================================================
 
  // NOTE: This sub-pipeline ingests arbitrary MLIR Vector code.
  buildCanonicalizeVectorForAIEVec(
      pm, options.getCanonicalizeVectorForAIEVecOptions());
  // NOTE: At this stage, all the Vector code in the IR can be mapped
  // NOTE: to AIEVec operations.
 
  //============================================================================
  // Vector to AIEVec lowering: Vector to AIEVec conversion.
  //============================================================================
 
  // NOTE: This sub-pipeline ingests MLIR Vector code that can be mapped to
  // NOTE: AIEVec operations.
  buildLowerVectorToAIEVec(pm, options.getLowerVectorToAIEVecOptions());
  // NOTE: At this stage, all vector operations are expressed in AIEVec dialect.
 
  //============================================================================
  // AIEVec optimization: AIEVec to AIEVec conversion.
  //============================================================================
 
  // NOTE: This sub-pipeline ingests AIEVec operations.
  buildOptimizeAIEVec(pm, options.getOptimizeAIEVecOptions());
 
  // Post-conversion passes.
  pm.addPass(createLoopInvariantCodeMotionPass());
  pm.addPass(createCanonicalizerPass());
}
 
//===---------------------------------------------------------------------------
// Pipeline registration
//===---------------------------------------------------------------------------
void xilinx::aievec::registerAIEVecPipelines() {
  PassPipelineRegistration<ConvertVectorToAIEVecOptions>(
      "convert-vector-to-aievec",
      "This pass pipeline takes standard \"Vector\" code and converts it to "
      "\"AIEVec\" code targeting the selected Xilinx AIE vector "
      "architecture.",
      buildConvertVectorToAIEVec);
 
  PassPipelineRegistration<CanonicalizeVectorForAIEVecOptions>(
      "canonicalize-vector-for-aievec",
      "This pass pipeline takes standard \"Vector\" code and converts it to "
      "\"Vector\" code compatible with the selected AIE vector architecture.",
      buildCanonicalizeVectorForAIEVec);
 
  PassPipelineRegistration<LowerVectorToAIEVecOptions>(
      "lower-vector-to-aievec",
      "This pass pipeline takes AIE-compatible \"Vector\" code and lowers it "
      "to \"AIE\" vector code targeting the selected AIE vector "
      "architecture.",
      buildLowerVectorToAIEVec);
 
  PassPipelineRegistration<OptimizeAIEVecOptions>(
      "optimize-aievec",
      "This pass pipeline takes AIE vector code and applies target-specific "
      "optimizations.",
      buildOptimizeAIEVec);
 
  PassPipelineRegistration<>(
      "dynamic-size-no-implicit-broadcast",
      "This pass pipeline rewrites arith operations when assuming no implict "
      "broadcast of dynamic sizes",
      buildDynamicSizeNoImplicitBroadcastPass);
}