mlir/test/lib/Dialect/LLVM/TestLowerToLLVM.cpp

   1 //===- TestLowerToLLVM.cpp - Test lowering to LLVM as a sink pass ---------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 //
   9 // This file implements a pass for testing the lowering to LLVM as a generally
  10 // usable sink pass.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #include "mlir/Conversion/AffineToStandard/AffineToStandard.h"
  15 #include "mlir/Conversion/FuncToLLVM/ConvertFuncToLLVMPass.h"
  16 #include "mlir/Conversion/IndexToLLVM/IndexToLLVM.h"
  17 #include "mlir/Conversion/MathToLLVM/MathToLLVM.h"
  18 #include "mlir/Conversion/MemRefToLLVM/MemRefToLLVM.h"
  19 #include "mlir/Conversion/ReconcileUnrealizedCasts/ReconcileUnrealizedCasts.h"
  20 #include "mlir/Conversion/SCFToControlFlow/SCFToControlFlow.h"
  21 #include "mlir/Conversion/VectorToLLVM/ConvertVectorToLLVMPass.h"
  22 #include "mlir/Conversion/VectorToSCF/VectorToSCF.h"
  23 #include "mlir/Dialect/Func/IR/FuncOps.h"
  24 #include "mlir/Dialect/LLVMIR/LLVMDialect.h"
  25 #include "mlir/Dialect/Linalg/Passes.h"
  26 #include "mlir/Dialect/MemRef/Transforms/Passes.h"
  27 #include "mlir/IR/DialectRegistry.h"
  28 #include "mlir/Pass/Pass.h"
  29 #include "mlir/Pass/PassManager.h"
  30 #include "mlir/Pass/PassOptions.h"
  31 #include "mlir/Transforms/Passes.h"
  32
  33 using namespace mlir;
  34
  35 namespace {
  36 struct TestLowerToLLVMOptions
  37     : public PassPipelineOptions<TestLowerToLLVMOptions> {
  38   PassOptions::Option<bool> reassociateFPReductions{
  39       *this, "reassociate-fp-reductions",
  40       llvm::cl::desc("Allow reassociation og FP reductions"),
  41       llvm::cl::init(false)};
  42 };
  43
  44 void buildTestLowerToLLVM(OpPassManager &pm,
  45                           const TestLowerToLLVMOptions &options) {
  46
  47   // TODO: it is feasible to scope lowering at arbitrary level and introduce
  48   // unrealized casts, but there needs to be the final module-wise cleanup in
  49   // the end. Keep module-level for now.
  50
  51   // Blanket-convert any remaining high-level vector ops to loops if any remain.
  52   pm.addNestedPass<func::FuncOp>(createConvertVectorToSCFPass());
  53   // Blanket-convert any remaining linalg ops to loops if any remain.
  54   pm.addNestedPass<func::FuncOp>(createConvertLinalgToLoopsPass());
  55   // Blanket-convert any remaining affine ops if any remain.
  56   pm.addPass(createLowerAffinePass());
  57   // Convert SCF to CF (always needed).
  58   pm.addPass(createConvertSCFToCFPass());
  59   // Sprinkle some cleanups.
  60   pm.addPass(createCanonicalizerPass());
  61   pm.addPass(createCSEPass());
  62   // Convert vector to LLVM (always needed).
  63   pm.addPass(createConvertVectorToLLVMPass(
  64       // TODO: add more options on a per-need basis.
  65       ConvertVectorToLLVMPassOptions{options.reassociateFPReductions}));
  66   // Convert Math to LLVM (always needed).
  67   pm.addNestedPass<func::FuncOp>(createConvertMathToLLVMPass());
  68   // Expand complicated MemRef operations before lowering them.
  69   pm.addPass(memref::createExpandStridedMetadataPass());
  70   // The expansion may create affine expressions. Get rid of them.
  71   pm.addPass(createLowerAffinePass());
  72   // Convert MemRef to LLVM (always needed).
  73   pm.addPass(createFinalizeMemRefToLLVMConversionPass());
  74   // Convert Func to LLVM (always needed).
  75   pm.addPass(createConvertFuncToLLVMPass());
  76   // Convert Index to LLVM (always needed).
  77   pm.addPass(createConvertIndexToLLVMPass());
  78   // Convert remaining unrealized_casts (always needed).
  79   pm.addPass(createReconcileUnrealizedCastsPass());
  80 }
  81 } // namespace
  82
  83 namespace mlir {
  84 namespace test {
  85 void registerTestLowerToLLVM() {
  86   PassPipelineRegistration<TestLowerToLLVMOptions>(
  87       "test-lower-to-llvm",
  88       "An example of pipeline to lower the main dialects (arith, linalg, "
  89       "memref, scf, vector) down to LLVM.",
  90       buildTestLowerToLLVM);
  91 }
  92 } // namespace test
  93 } // namespace mlir