[mlir][Linalg] Start a LinalgToStandard pass and move conversion to library calls.

[nicolasvasilache]

Summary

This revision starts decoupling the include the kitchen sink behavior of Linalg to LLVM lowering by inserting a -convert-linalg-to-std pass.

The lowering of linalg ops to function calls was previously lowering to memref descriptors by having both linalg -> std and std -> LLVM patterns in the same rewrite.

When separating this step, a new issue occurred: the layout is automatically type-erased by this process. This revision therefore introduces memref casts to perform these type erasures explicitly. To connect everything end-to-end, the LLVM lowering of MemRefCastOp is relaxed because it is artificially more restricted than the op semantics. The op semantics already guarantee that source and target MemRefTypes are cast-compatible. An invalid lowering test now becomes valid and is removed.

[bondhugula]

mlir/lib/Conversion/LinalgToLLVM/LinalgToLLVM.cpp

352

Can LinAlgToLLVM now be completely removed? Do you still need anything in it? I couldn't immediately tell from the commit summary and this diff.

[bondhugula]

mlir/test/mlir-cpu-runner/linalg_integration_test.mlir

1

I see you still have all those reshape/slice/transpose being converted directly from linalg to llvm instead of via std.view/subview.

[nicolasvasilache]

mlir/lib/Conversion/LinalgToLLVM/LinalgToLLVM.cpp

352

Not yet, I'm doing it in a staged fashion but the endgoal is indeed to remove it.

mlir/test/mlir-cpu-runner/linalg_integration_test.mlir

1

Yes for now this is still the case.

[ftynse]

I think you need to relax the semantics of memref_cast first. It currently says (emphasis mine)

The memref_cast operation converts a memref from one type to an equivalent type with a compatible shape. The source and destination types are compatible if: a. both are ranked memref types with the same element type, affine mappings, address space, and rank but where the individual dimensions may add or remove constant dimensions from the memref type.

so the new uses introduced here and the their lowering directly contradict what is stated in the doc. (I am surprised we don't have a verifier to check it). I am not fundamentally opposed to such relaxation, but we may want to consider introducing a separate, more dangerous cast operation, similarly to static_cast/reinterpret_cast different in C++. The layout-changing cast may create out-of-bounds accesses whereas static/dynamic info cast will never do that.

mlir/lib/Conversion/LinalgToStandard/LinalgToStandard.cpp

20

Document this plz

46

result.resize(numLoops, IndexType::get(ctx)); spares you a loop

104

How about storing the result of b.create in a variable and then pushing it back? It will likely be less LoC and more readable at the same time.

106

I don't recall memref_cast, or its lowering, to support layout changes. It can add or remove static information, but a memref without an explicit layout map just has an implicit row-major layout. Did you mean to cast it to unranked memref maybe?

[nicolasvasilache]

so the new uses introduced here and the their lowering directly contradict what is stated in the doc.

Here, I fixed it :)

The `memref_cast` operation converts a memref from one type to an equivalent
type with a compatible shape. The source and destination types are
compatible if both are ranked memref types with the same element type,
address space, and rank but where the individual dimensions may add or
remove constant dimensions from the memref type.

More seriously, I think this is an oversight since the doc examples and the impl contradict the "same layout" part.

[ftynse]

In D79468#2030763, @nicolasvasilache wrote:

so the new uses introduced here and the their lowering directly contradict what is stated in the doc.

Here, I fixed it :)

The `memref_cast` operation converts a memref from one type to an equivalent
type with a compatible shape. The source and destination types are
compatible if both are ranked memref types with the same element type,
address space, and rank but where the individual dimensions may add or
remove constant dimensions from the memref type.

More seriously, I think this is an oversight since the doc examples and the impl contradict the "same layout" part.

This change still doesn't fit my mental model of casts (the model may be wrong, but it is likely an evidence of insufficient documentation). The change drops the layout unconditionally. Let's assume we cannot have a non-strided layout because all memrefs come from Linalg (may be worth an assert and/or a comment). When you cast from memref<4x8xf32, offset:0, strides: [1,4]> to memref<4x8xf32>, the strides practically become [8,1], which doesn't look desirable.

[nicolasvasilache]

Address review comments.

[nicolasvasilache]

Update the MemRefCastOp doc.

[nicolasvasilache]

@ftynse also updated the condition breakdown in the doc to match the verifier, lmk if that looks more reasonable.

Thanks!

[ftynse]

Makes senes now, thanks!

[nicolasvasilache]

Rebase.

[rriddle]

mlir/include/mlir/Conversion/LinalgToStandard/LinalgToStandard.h

13

Can we trim this include?

mlir/include/mlir/Conversion/Passes.td

158

Should this come after SPIRV alphabetically?

[mehdi_amini]

@nicolasvasilache : did you address the post-commit review comments?

mlir/include/mlir/Conversion/LinalgToStandard/LinalgToStandard.h

+//===- LinalgToStandard.h - Utils to convert from the linalg 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
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef MLIR_CONVERSION_LINALGTOSTANDARD_LINALGTOSTANDARD_H_
+#define MLIR_CONVERSION_LINALGTOSTANDARD_LINALGTOSTANDARD_H_
+
+#include "mlir/Transforms/DialectConversion.h"
+
+namespace mlir {
+class MLIRContext;
+class ModuleOp;
+template <typename T>
+class OperationPass;
+
+/// Populate the given list with patterns that convert from Linalg to Standard.
+void populateLinalgToStandardConversionPatterns(
+    OwningRewritePatternList &patterns, MLIRContext *ctx);
+
+/// Create a pass to convert Linalg operations to the Standard dialect.
+std::unique_ptr<OperationPass<ModuleOp>> createConvertLinalgToStandardPass();
+
+} // namespace mlir
+
+#endif // MLIR_CONVERSION_LINALGTOSTANDARD_LINALGTOSTANDARD_H_

mlir/include/mlir/Conversion/Passes.td

 
 def ConvertLinalgToLLVM : Pass<"convert-linalg-to-llvm", "ModuleOp"> {
   let summary = "Convert the operations from the linalg dialect into the LLVM "
                 "dialect";
   let constructor = "mlir::createConvertLinalgToLLVMPass()";
 }
 
 //===----------------------------------------------------------------------===//
+// LinalgToStandard
+//===----------------------------------------------------------------------===//
+
+def ConvertLinalgToStandard : Pass<"convert-linalg-to-std", "ModuleOp"> {
+  let summary = "Convert the operations from the linalg dialect into the "
+                "Standard dialect";
+  let constructor = "mlir::createConvertLinalgToStandardPass()";
+}
+
+//===----------------------------------------------------------------------===//
 // LinalgToSPIRV
 //===----------------------------------------------------------------------===//
 
 def ConvertLinalgToSPIRV : Pass<"convert-linalg-to-spirv", "ModuleOp"> {
   let summary = "Convert Linalg ops to SPIR-V ops";
   let constructor = "mlir::createLinalgToSPIRVPass()";
 }
 
 //===----------------------------------------------------------------------===//
 // LoopToStandard
 //===----------------------------------------------------------------------===//
 

mlir/include/mlir/InitAllPasses.h

 #include "mlir/Conversion/AVX512ToLLVM/ConvertAVX512ToLLVM.h"
 #include "mlir/Conversion/GPUToCUDA/GPUToCUDAPass.h"
 #include "mlir/Conversion/GPUToNVVM/GPUToNVVMPass.h"
 #include "mlir/Conversion/GPUToROCDL/GPUToROCDLPass.h"
 #include "mlir/Conversion/GPUToSPIRV/ConvertGPUToSPIRVPass.h"
 #include "mlir/Conversion/GPUToVulkan/ConvertGPUToVulkanPass.h"
 #include "mlir/Conversion/LinalgToLLVM/LinalgToLLVM.h"
 #include "mlir/Conversion/LinalgToSPIRV/LinalgToSPIRVPass.h"
+#include "mlir/Conversion/LinalgToStandard/LinalgToStandard.h"
 #include "mlir/Conversion/LoopToStandard/ConvertLoopToStandard.h"
 #include "mlir/Conversion/LoopsToGPU/LoopsToGPUPass.h"
 #include "mlir/Conversion/StandardToLLVM/ConvertStandardToLLVMPass.h"
 #include "mlir/Conversion/StandardToSPIRV/ConvertStandardToSPIRVPass.h"
 #include "mlir/Conversion/VectorToLLVM/ConvertVectorToLLVM.h"
 #include "mlir/Dialect/Affine/Passes.h"
 #include "mlir/Dialect/GPU/Passes.h"
 #include "mlir/Dialect/LLVMIR/Transforms/LegalizeForExport.h"

mlir/lib/Conversion/CMakeLists.txt

 add_subdirectory(AffineToStandard)
 add_subdirectory(AVX512ToLLVM)
 add_subdirectory(GPUToCUDA)
 add_subdirectory(GPUToNVVM)
 add_subdirectory(GPUToROCDL)
 add_subdirectory(GPUToSPIRV)
 add_subdirectory(GPUToVulkan)
 add_subdirectory(LinalgToLLVM)
 add_subdirectory(LinalgToSPIRV)
+add_subdirectory(LinalgToStandard)
 add_subdirectory(LoopsToGPU)
 add_subdirectory(LoopToStandard)
 add_subdirectory(StandardToLLVM)
 add_subdirectory(StandardToSPIRV)
 add_subdirectory(StandardToStandard)
 add_subdirectory(VectorToLLVM)
 add_subdirectory(VectorToLoops)

mlir/lib/Conversion/LinalgToLLVM/LinalgToLLVM.cpp

public:
   matchAndRewrite(Operation *op, ArrayRef<Value> operands,
                   ConversionPatternRewriter &rewriter) const override {
     rewriter.replaceOpWithNewOp<LLVM::ReturnOp>(op, operands);
     return success();
   }
 };
 } // namespace
 
-template <typename LinalgOp>
-static SmallVector<Type, 4> ExtractOperandTypes(Operation *op) {
-  return SmallVector<Type, 4>{op->getOperandTypes()};
-}
-
-template <>
-SmallVector<Type, 4> ExtractOperandTypes<IndexedGenericOp>(Operation *op) {
-  auto ctx = op->getContext();
-  auto indexedGenericOp = cast<IndexedGenericOp>(op);
-  auto numLoops = indexedGenericOp.getNumLoops();
-
-  SmallVector<Type, 4> result;
-  result.reserve(numLoops + op->getNumOperands());
-  for (unsigned i = 0; i < numLoops; ++i) {
-    result.push_back(IndexType::get(ctx));
-  }
-  for (auto type : op->getOperandTypes()) {
-    result.push_back(type);
-  }
-  return result;
-}
-
-// Get a SymbolRefAttr containing the library function name for the LinalgOp.
-// If the library function does not exist, insert a declaration.
-template <typename LinalgOp>
-static FlatSymbolRefAttr getLibraryCallSymbolRef(Operation *op,
-                                                 PatternRewriter &rewriter) {
-  auto linalgOp = cast<LinalgOp>(op);
-  auto fnName = linalgOp.getLibraryCallName();
-  if (fnName.empty()) {
-    op->emitWarning("No library call defined for: ") << *op;
-    return {};
-  }
-
-  // fnName is a dynamic std::String, unique it via a SymbolRefAttr.
-  FlatSymbolRefAttr fnNameAttr = rewriter.getSymbolRefAttr(fnName);
-  auto module = op->getParentOfType<ModuleOp>();
-  if (module.lookupSymbol(fnName)) {
-    return fnNameAttr;
-  }
-
-  SmallVector<Type, 4> inputTypes(ExtractOperandTypes<LinalgOp>(op));
-  assert(op->getNumResults() == 0 &&
-         "Library call for linalg operation can be generated only for ops that "
-         "have void return types");
-  auto libFnType = FunctionType::get(inputTypes, {}, rewriter.getContext());
-
-  OpBuilder::InsertionGuard guard(rewriter);
-  // Insert before module terminator.
-  rewriter.setInsertionPoint(module.getBody(),
-                             std::prev(module.getBody()->end()));
-  FuncOp funcOp =
-      rewriter.create<FuncOp>(op->getLoc(), fnNameAttr.getValue(), libFnType,
-                              ArrayRef<NamedAttribute>{});
-  // Insert a function attribute that will trigger the emission of the
-  // corresponding `_mlir_ciface_xxx` interface so that external libraries see
-  // a normalized ABI. This interface is added during std to llvm conversion.
-  funcOp.setAttr("llvm.emit_c_interface", UnitAttr::get(op->getContext()));
-  return fnNameAttr;
-}
-
-namespace {
-
-// LinalgOpConversion<LinalgOp> creates a new call to the
-// `LinalgOp::getLibraryCallName()` function.
-// The implementation of the function can be either in the same module or in an
-// externally linked library.
-template <typename LinalgOp>
-class LinalgOpConversion : public OpRewritePattern<LinalgOp> {
-public:
-  using OpRewritePattern<LinalgOp>::OpRewritePattern;
-
-  LogicalResult matchAndRewrite(LinalgOp op,
-                                PatternRewriter &rewriter) const override {
-    auto libraryCallName = getLibraryCallSymbolRef<LinalgOp>(op, rewriter);
-    if (!libraryCallName)
-      return failure();
-
-    rewriter.replaceOpWithNewOp<mlir::CallOp>(
-        op, libraryCallName.getValue(), ArrayRef<Type>{}, op.getOperands());
-    return success();
-  }
-};
-
-/// Conversion pattern specialization for CopyOp. This kicks in when both input
-/// and output permutations are left unspecified or are the identity.
-template <> class LinalgOpConversion<CopyOp> : public OpRewritePattern<CopyOp> {
-public:
-  using OpRewritePattern<CopyOp>::OpRewritePattern;
-
-  LogicalResult matchAndRewrite(CopyOp op,
-                                PatternRewriter &rewriter) const override {
-    auto inputPerm = op.inputPermutation();
-    if (inputPerm.hasValue() && !inputPerm->isIdentity())
-      return failure();
-    auto outputPerm = op.outputPermutation();
-    if (outputPerm.hasValue() && !outputPerm->isIdentity())
-      return failure();
-
-    auto libraryCallName = getLibraryCallSymbolRef<CopyOp>(op, rewriter);
-    if (!libraryCallName)
-      return failure();
-
-    rewriter.replaceOpWithNewOp<mlir::CallOp>(
-        op, libraryCallName.getValue(), ArrayRef<Type>{}, op.getOperands());
-    return success();
-  }
-};
-
-/// Conversion pattern specialization for IndexedGenericOp.
-template <>
-class LinalgOpConversion<IndexedGenericOp>
-    : public OpRewritePattern<IndexedGenericOp> {
-public:
-  using OpRewritePattern<IndexedGenericOp>::OpRewritePattern;
-
-  LogicalResult matchAndRewrite(IndexedGenericOp op,
-                                PatternRewriter &rewriter) const override {
-    auto libraryCallName =
-        getLibraryCallSymbolRef<IndexedGenericOp>(op, rewriter);
-    if (!libraryCallName)
-      return failure();
-
-    // TODO(pifon, ntv): Use induction variables values instead of zeros, when
-    // IndexedGenericOp is tiled.
-    auto zero = rewriter.create<mlir::ConstantOp>(
-        op.getLoc(), rewriter.getIntegerAttr(rewriter.getIndexType(), 0));
-    auto indexedGenericOp = cast<IndexedGenericOp>(op);
-    auto numLoops = indexedGenericOp.getNumLoops();
-    SmallVector<Value, 4> operands;
-    operands.reserve(numLoops + op.getNumOperands());
-    for (unsigned i = 0; i < numLoops; ++i) {
-      operands.push_back(zero);
-    }
-    for (auto operand : op.getOperands()) {
-      operands.push_back(operand);
-    }
-    rewriter.replaceOpWithNewOp<mlir::CallOp>(op, libraryCallName.getValue(),
-                                              ArrayRef<Type>{}, operands);
-    return success();
-  }
-};
-
-/// A non-conversion rewrite pattern kicks in to convert CopyOp with
-/// permutations into a sequence of TransposeOp and permutation-free CopyOp.
-/// This interplays together with TransposeOpConversion and
-/// LinalgConversion<CopyOp> to create a path to the LLVM dialect.
-class CopyTransposeConversion : public OpRewritePattern<CopyOp> {
-public:
-  using OpRewritePattern<CopyOp>::OpRewritePattern;
-
-  LogicalResult matchAndRewrite(CopyOp op,
-                                PatternRewriter &rewriter) const override {
-    Value in = op.input(), out = op.output();
-
-    // If either inputPerm or outputPerm are non-identities, insert transposes.
-    auto inputPerm = op.inputPermutation();
-    if (inputPerm.hasValue() && !inputPerm->isIdentity())
-      in = rewriter.create<linalg::TransposeOp>(op.getLoc(), in,
-                                                AffineMapAttr::get(*inputPerm));
-    auto outputPerm = op.outputPermutation();
-    if (outputPerm.hasValue() && !outputPerm->isIdentity())
-      out = rewriter.create<linalg::TransposeOp>(
-          op.getLoc(), out, AffineMapAttr::get(*outputPerm));
-
-    // If nothing was transposed, fail and let the conversion kick in.
-    if (in == op.input() && out == op.output())
-      return failure();
-
-    rewriter.replaceOpWithNewOp<CopyOp>(op, in, out);
-    return success();
-  }
-};
-
-/// Populate the given list with patterns that convert from Linalg to Standard.
-static void
-populateLinalgToStandardConversionPatterns(OwningRewritePatternList &patterns,
-                                           MLIRContext *ctx) {
-  // TODO(ntv) ConvOp conversion needs to export a descriptor with relevant
-  // attribute values such as kernel striding and dilation.
-  // clang-format off
-  patterns.insert<
-      CopyTransposeConversion,
-      LinalgOpConversion<ConvOp>,
-      LinalgOpConversion<PoolingMaxOp>,
-      LinalgOpConversion<PoolingMinOp>,
-      LinalgOpConversion<PoolingSumOp>,
-      LinalgOpConversion<CopyOp>,
-      LinalgOpConversion<DotOp>,
-      LinalgOpConversion<FillOp>,
-      LinalgOpConversion<GenericOp>,
-      LinalgOpConversion<IndexedGenericOp>,
-      LinalgOpConversion<MatmulOp>,
-      LinalgOpConversion<MatvecOp>>(ctx);
-  // clang-format on
-}
-
-} // namespace
-
 /// Populate the given list with patterns that convert from Linalg to LLVM.
 void mlir::populateLinalgToLLVMConversionPatterns(
     LLVMTypeConverter &converter, OwningRewritePatternList &patterns,
     MLIRContext *ctx) {
   patterns.insert<RangeOpConversion, ReshapeOpConversion, SliceOpConversion,
                   TransposeOpConversion, YieldOpConversion>(ctx, converter);
 
   // Populate the type conversions for the linalg types.
void ConvertLinalgToLLVMPass::runOnOperation() {
   OwningRewritePatternList patterns;
   LLVMTypeConverter converter(&getContext());
   populateAffineToStdConversionPatterns(patterns, &getContext());
   populateLoopToStdConversionPatterns(patterns, &getContext());
   populateStdToLLVMConversionPatterns(converter, patterns);
   populateVectorToLoopsConversionPatterns(patterns, &getContext());
   populateVectorToLLVMMatrixConversionPatterns(converter, patterns);
   populateVectorToLLVMConversionPatterns(converter, patterns);
-  populateLinalgToStandardConversionPatterns(patterns, &getContext());
   populateLinalgToLLVMConversionPatterns(converter, patterns, &getContext());
 
   LLVMConversionTarget target(getContext());
   target.addDynamicallyLegalOp<FuncOp>(
       [&](FuncOp op) { return converter.isSignatureLegal(op.getType()); });
   target.addLegalOp<ModuleOp, ModuleTerminatorOp>();
   if (failed(applyFullConversion(module, target, patterns, &converter)))
     signalPassFailure();
 }
 
 std::unique_ptr<OperationPass<ModuleOp>> mlir::createConvertLinalgToLLVMPass() {
   return std::make_unique<ConvertLinalgToLLVMPass>();
 }

mlir/lib/Conversion/LinalgToStandard/CMakeLists.txt

+add_mlir_conversion_library(MLIRLinalgToStandard
+  LinalgToStandard.cpp
+
+  ADDITIONAL_HEADER_DIRS
+  ${MLIR_MAIN_INCLUDE_DIR}/mlir/Conversion/LinalgToStandard
+
+  DEPENDS
+  MLIRConversionPassIncGen
+)
+
+target_link_libraries(MLIRLinalgToStandard
+  PUBLIC
+  MLIREDSC
+  MLIRIR
+  MLIRLinalgOps
+  LLVMCore
+  LLVMSupport
+  )

mlir/lib/Conversion/LinalgToStandard/LinalgToStandard.cpp

+//===- LinalgToStandard.cpp - conversion from Linalg to Standard 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/LinalgToStandard/LinalgToStandard.h"
+
+#include "../PassDetail.h"
+#include "mlir/Dialect/Affine/IR/AffineOps.h"
+#include "mlir/Dialect/Linalg/IR/LinalgOps.h"
+#include "mlir/Dialect/LoopOps/LoopOps.h"
+#include "mlir/Dialect/StandardOps/IR/Ops.h"
+
+using namespace mlir;
+using namespace mlir::linalg;
+
+template <typename LinalgOp>
+static SmallVector<Type, 4> extractOperandTypes(Operation *op) {
+  SmallVector<Type, 4> result;
+  result.reserve(op->getNumOperands());
+  for (auto type : op->getOperandTypes()) {
+    // The underlying descriptor type (e.g. LLVM) does not have layout
+    // information. Erasing the type at the level of std when going into a
+    // library call avoids needing to introduce DialectCastOp.
+    if (auto memrefType = type.dyn_cast<MemRefType>())
+      result.push_back(MemRefType::get(memrefType.getShape(),
+                                       memrefType.getElementType(), {},
+                                       memrefType.getMemorySpace()));
+    else
+      result.push_back(type);
+  }
+  return result;
+}
+
+template <>
+SmallVector<Type, 4> extractOperandTypes<IndexedGenericOp>(Operation *op) {
+  auto *ctx = op->getContext();
+  auto indexedGenericOp = cast<IndexedGenericOp>(op);
+  auto numLoops = indexedGenericOp.getNumLoops();
+
+  SmallVector<Type, 4> result;
+  result.reserve(numLoops + op->getNumOperands());
+  for (unsigned i = 0; i < numLoops; ++i)
+    result.push_back(IndexType::get(ctx));
+  auto typeErasedOperands = extractOperandTypes<LinalgOp>(op);
+  result.append(typeErasedOperands.begin(), typeErasedOperands.end());
+  return result;
+}
+
+// Get a SymbolRefAttr containing the library function name for the LinalgOp.
+// If the library function does not exist, insert a declaration.
+template <typename LinalgOp>
+static FlatSymbolRefAttr getLibraryCallSymbolRef(Operation *op,
+                                                 PatternRewriter &rewriter) {
+  auto linalgOp = cast<LinalgOp>(op);
+  auto fnName = linalgOp.getLibraryCallName();
+  if (fnName.empty()) {
+    op->emitWarning("No library call defined for: ") << *op;
+    return {};
+  }
+
+  // fnName is a dynamic std::string, unique it via a SymbolRefAttr.
+  FlatSymbolRefAttr fnNameAttr = rewriter.getSymbolRefAttr(fnName);
+  auto module = op->getParentOfType<ModuleOp>();
+  if (module.lookupSymbol(fnName)) {
+    return fnNameAttr;
+  }
+
+  SmallVector<Type, 4> inputTypes(extractOperandTypes<LinalgOp>(op));
+  assert(op->getNumResults() == 0 &&
+         "Library call for linalg operation can be generated only for ops that "
+         "have void return types");
+  auto libFnType = FunctionType::get(inputTypes, {}, rewriter.getContext());
+
+  OpBuilder::InsertionGuard guard(rewriter);
+  // Insert before module terminator.
+  rewriter.setInsertionPoint(module.getBody(),
+                             std::prev(module.getBody()->end()));
+  FuncOp funcOp =
+      rewriter.create<FuncOp>(op->getLoc(), fnNameAttr.getValue(), libFnType,
+                              ArrayRef<NamedAttribute>{});
+  // Insert a function attribute that will trigger the emission of the
+  // corresponding `_mlir_ciface_xxx` interface so that external libraries see
+  // a normalized ABI. This interface is added during std to llvm conversion.
+  funcOp.setAttr("llvm.emit_c_interface", UnitAttr::get(op->getContext()));
+  return fnNameAttr;
+}
+
+namespace {
+
+SmallVector<Value, 4> createTypeErasedMemRefOperands(OpBuilder &b, Location loc,
+                                                     ValueRange operands) {
+  SmallVector<Value, 4> res;
+  res.reserve(operands.size());
+  for (auto op : operands) {
+    auto memrefType = op.getType().dyn_cast<MemRefType>();
+    if (!memrefType || memrefType.getAffineMaps().empty()) {
+      res.push_back(op);
+      continue;
+    }
+    res.push_back(b.create<MemRefCastOp>(
+        loc,
+        MemRefType::get(memrefType.getShape(), memrefType.getElementType(), {},
+                        memrefType.getMemorySpace()),
+        op));
+  }
+  return res;
+}
+
+// LinalgOpConversion<LinalgOp> creates a new call to the type-erased
+// `LinalgOp::getLibraryCallName()` function.
+// The implementation of the function can be either in the same module or in an
+// externally linked library.
+template <typename LinalgOp>
+class LinalgOpConversion : public OpRewritePattern<LinalgOp> {
+public:
+  using OpRewritePattern<LinalgOp>::OpRewritePattern;
+
+  LogicalResult matchAndRewrite(LinalgOp op,
+                                PatternRewriter &rewriter) const override {
+    auto libraryCallName = getLibraryCallSymbolRef<LinalgOp>(op, rewriter);
+    if (!libraryCallName)
+      return failure();
+
+    rewriter.replaceOpWithNewOp<mlir::CallOp>(
+        op, libraryCallName.getValue(), ArrayRef<Type>{},
+        createTypeErasedMemRefOperands(rewriter, op.getLoc(),
+                                       op.getOperands()));
+    return success();
+  }
+};
+
+/// Conversion pattern specialization for CopyOp. This kicks in when both input
+/// and output permutations are left unspecified or are the identity.
+template <>
+class LinalgOpConversion<CopyOp> : public OpRewritePattern<CopyOp> {
+public:
+  using OpRewritePattern<CopyOp>::OpRewritePattern;
+
+  LogicalResult matchAndRewrite(CopyOp op,
+                                PatternRewriter &rewriter) const override {
+    auto inputPerm = op.inputPermutation();
+    if (inputPerm.hasValue() && !inputPerm->isIdentity())
+      return failure();
+    auto outputPerm = op.outputPermutation();
+    if (outputPerm.hasValue() && !outputPerm->isIdentity())
+      return failure();
+
+    auto libraryCallName = getLibraryCallSymbolRef<CopyOp>(op, rewriter);
+    if (!libraryCallName)
+      return failure();
+
+    rewriter.replaceOpWithNewOp<mlir::CallOp>(
+        op, libraryCallName.getValue(), ArrayRef<Type>{},
+        createTypeErasedMemRefOperands(rewriter, op.getLoc(),
+                                       op.getOperands()));
+    return success();
+  }
+};
+
+/// Conversion pattern specialization for IndexedGenericOp.
+template <>
+class LinalgOpConversion<IndexedGenericOp>
+    : public OpRewritePattern<IndexedGenericOp> {
+public:
+  using OpRewritePattern<IndexedGenericOp>::OpRewritePattern;
+
+  LogicalResult matchAndRewrite(IndexedGenericOp op,
+                                PatternRewriter &rewriter) const override {
+    auto libraryCallName =
+        getLibraryCallSymbolRef<IndexedGenericOp>(op, rewriter);
+    if (!libraryCallName)
+      return failure();
+
+    // TODO(pifon, ntv): Use induction variables values instead of zeros, when
+    // IndexedGenericOp is tiled.
+    auto zero = rewriter.create<mlir::ConstantOp>(
+        op.getLoc(), rewriter.getIntegerAttr(rewriter.getIndexType(), 0));
+    auto indexedGenericOp = cast<IndexedGenericOp>(op);
+    auto numLoops = indexedGenericOp.getNumLoops();
+    SmallVector<Value, 4> operands;
+    operands.reserve(numLoops + op.getNumOperands());
+    for (unsigned i = 0; i < numLoops; ++i)
+      operands.push_back(zero);
+    for (auto operand : op.getOperands())
+      operands.push_back(operand);
+    rewriter.replaceOpWithNewOp<mlir::CallOp>(
+        op, libraryCallName.getValue(), ArrayRef<Type>{},
+        createTypeErasedMemRefOperands(rewriter, op.getLoc(), operands));
+    return success();
+  }
+};
+
+/// A non-conversion rewrite pattern kicks in to convert CopyOp with
+/// permutations into a sequence of TransposeOp and permutation-free CopyOp.
+/// This interplays together with TransposeOpConversion and
+/// LinalgConversion<CopyOp> to create a path to the LLVM dialect.
+class CopyTransposeConversion : public OpRewritePattern<CopyOp> {
+public:
+  using OpRewritePattern<CopyOp>::OpRewritePattern;
+
+  LogicalResult matchAndRewrite(CopyOp op,
+                                PatternRewriter &rewriter) const override {
+    Value in = op.input(), out = op.output();
+
+    // If either inputPerm or outputPerm are non-identities, insert transposes.
+    auto inputPerm = op.inputPermutation();
+    if (inputPerm.hasValue() && !inputPerm->isIdentity())
+      in = rewriter.create<linalg::TransposeOp>(op.getLoc(), in,
+                                                AffineMapAttr::get(*inputPerm));
+    auto outputPerm = op.outputPermutation();
+    if (outputPerm.hasValue() && !outputPerm->isIdentity())
+      out = rewriter.create<linalg::TransposeOp>(
+          op.getLoc(), out, AffineMapAttr::get(*outputPerm));
+
+    // If nothing was transposed, fail and let the conversion kick in.
+    if (in == op.input() && out == op.output())
+      return failure();
+
+    rewriter.replaceOpWithNewOp<CopyOp>(op, in, out);
+    return success();
+  }
+};
+} // namespace
+
+/// Populate the given list with patterns that convert from Linalg to Standard.
+void mlir::populateLinalgToStandardConversionPatterns(
+    OwningRewritePatternList &patterns, MLIRContext *ctx) {
+  // TODO(ntv) ConvOp conversion needs to export a descriptor with relevant
+  // attribute values such as kernel striding and dilation.
+  // clang-format off
+  patterns.insert<
+      CopyTransposeConversion,
+      LinalgOpConversion<ConvOp>,
+      LinalgOpConversion<PoolingMaxOp>,
+      LinalgOpConversion<PoolingMinOp>,
+      LinalgOpConversion<PoolingSumOp>,
+      LinalgOpConversion<CopyOp>,
+      LinalgOpConversion<DotOp>,
+      LinalgOpConversion<FillOp>,
+      LinalgOpConversion<GenericOp>,
+      LinalgOpConversion<IndexedGenericOp>,
+      LinalgOpConversion<MatmulOp>,
+      LinalgOpConversion<MatvecOp>>(ctx);
+  // clang-format on
+}
+
+namespace {
+struct ConvertLinalgToStandardPass
+    : public ConvertLinalgToStandardBase<ConvertLinalgToStandardPass> {
+  void runOnOperation() override;
+};
+} // namespace
+
+void ConvertLinalgToStandardPass::runOnOperation() {
+  auto module = getOperation();
+  ConversionTarget target(getContext());
+  target.addLegalDialect<AffineDialect, loop::LoopOpsDialect,
+                         StandardOpsDialect>();
+  target.addLegalOp<ModuleOp, FuncOp, ModuleTerminatorOp, ReturnOp>();
+  target.addLegalOp<linalg::TransposeOp, linalg::ReshapeOp, linalg::RangeOp>();
+  OwningRewritePatternList patterns;
+  populateLinalgToStandardConversionPatterns(patterns, &getContext());
+  if (failed(applyFullConversion(module, target, patterns)))
+    signalPassFailure();
+}
+
+std::unique_ptr<OperationPass<ModuleOp>>
+mlir::createConvertLinalgToStandardPass() {
+  return std::make_unique<ConvertLinalgToStandardPass>();
+}

mlir/lib/Conversion/StandardToLLVM/StandardToLLVM.cpp

 struct MemRefCastOpLowering : public ConvertOpToLLVMPattern<MemRefCastOp> {
   using ConvertOpToLLVMPattern<MemRefCastOp>::ConvertOpToLLVMPattern;
 
   LogicalResult match(Operation *op) const override {
     auto memRefCastOp = cast<MemRefCastOp>(op);
     Type srcType = memRefCastOp.getOperand().getType();
     Type dstType = memRefCastOp.getType();
 
-    if (srcType.isa<MemRefType>() && dstType.isa<MemRefType>()) {
-      MemRefType sourceType =
-          memRefCastOp.getOperand().getType().cast<MemRefType>();
-      MemRefType targetType = memRefCastOp.getType().cast<MemRefType>();
-      return (isSupportedMemRefType(targetType) &&
-              isSupportedMemRefType(sourceType))
-                 ? success()
-                 : failure();
-    }
+    // MemRefCastOp reduce to bitcast in the ranked MemRef case and can be used
+    // for type erasure. For now they must preserve underlying element type and
+    // require source and result type to have the same rank. Therefore, perform
+    // a sanity check that the underlying structs are the same. Once op
+    // semantics are relaxed we can revisit.
+    if (srcType.isa<MemRefType>() && dstType.isa<MemRefType>())
+      return success(typeConverter.convertType(srcType) ==
+                     typeConverter.convertType(dstType));
 
     // At least one of the operands is unranked type
     assert(srcType.isa<UnrankedMemRefType>() ||
            dstType.isa<UnrankedMemRefType>());
 
     // Unranked to unranked cast is disallowed
     return !(srcType.isa<UnrankedMemRefType>() &&
              dstType.isa<UnrankedMemRefType>())
                ? success()
                : failure();
   }
 
   void rewrite(Operation *op, ArrayRef<Value> operands,
                ConversionPatternRewriter &rewriter) const override {
     auto memRefCastOp = cast<MemRefCastOp>(op);
     OperandAdaptor<MemRefCastOp> transformed(operands);
 
     auto srcType = memRefCastOp.getOperand().getType();
     auto dstType = memRefCastOp.getType();
     auto targetStructType = typeConverter.convertType(memRefCastOp.getType());
     auto loc = op->getLoc();
 
+    // MemRefCastOp reduce to bitcast in the ranked MemRef case.
     if (srcType.isa<MemRefType>() && dstType.isa<MemRefType>()) {
-      // memref_cast is defined for source and destination memref types with the
-      // same element type, same mappings, same address space and same rank.
-      // Therefore a simple bitcast suffices. If not it is undefined behavior.
       rewriter.replaceOpWithNewOp<LLVM::BitcastOp>(op, targetStructType,
                                                    transformed.source());
     } else if (srcType.isa<MemRefType>() && dstType.isa<UnrankedMemRefType>()) {
       // Casting ranked to unranked memref type
       // Set the rank in the destination from the memref type
       // Allocate space on the stack and copy the src memref descriptor
       // Set the ptr in the destination to the stack space
       auto srcMemRefType = srcType.cast<MemRefType>();

mlir/test/Conversion/StandardToLLVM/invalid.mlir

 // RUN: mlir-opt %s -convert-std-to-llvm -verify-diagnostics -split-input-file
 
-#map1 = affine_map<(d0, d1)[s0, s1, s2] -> (d0 * s1 + s0 + d1 * s2)>
-
-func @invalid_memref_cast(%arg0: memref<?x?xf64>) {
-  %c1 = constant 1 : index
-  %c0 = constant 0 : index
-  // expected-error@+1 {{'std.memref_cast' op operand #0 must be unranked.memref of any type values or memref of any type values, but got '!llvm<"{ double*, double*, i64, [2 x i64], [2 x i64] }">'}}
-  %5 = memref_cast %arg0 : memref<?x?xf64> to memref<?x?xf64, #map1>
-  %25 = std.subview %5[%c0, %c0][%c1, %c1][] : memref<?x?xf64, #map1> to memref<?x?xf64, #map1>
-  return
-}
-
-// -----
-
 func @mlir_cast_to_llvm(%0 : index) -> !llvm.i64 {
   // expected-error@+1 {{'llvm.mlir.cast' op type must be non-index integer types, float types, or vector of mentioned types}}
   %1 = llvm.mlir.cast %0 : index to !llvm.i64
   return %1 : !llvm.i64
 }
 
 // -----
 

mlir/test/Dialect/Linalg/llvm.mlir

 // RUN: mlir-opt %s -convert-linalg-to-llvm | FileCheck %s
-// RUN: mlir-opt %s -convert-linalg-to-loops | FileCheck %s --check-prefix=LLVM-LOOPS
 
 func @range(%arg0: index) {
   %c0 = constant 0 : index
   %c1 = constant 1 : index
   %R = linalg.range %c0:%arg0:%c1 : !linalg.range
   return
 }
 // CHECK-LABEL: func @range(%{{.*}}: !llvm.i64) {

 //  CHECK-NEXT:   llvm.icmp "slt" %{{.*}}, %{{.*}} : !llvm.i64
 //  CHECK-NEXT:   llvm.select %{{.*}}, %{{.*}}, %{{.*}} : !llvm.i1, !llvm.i64
 //    compute stride[0] using bounded size
 //  CHECK-NEXT:   llvm.mul %{{.*}}, %{{.*}} : !llvm.i64
 //    insert size and stride
 //  CHECK-NEXT:   llvm.insertvalue %{{.*}}, %{{.*}}[3, 0] : !llvm<"{ float*, float*, i64, [1 x i64], [1 x i64] }">
 //  CHECK-NEXT:   llvm.insertvalue %{{.*}}, %{{.*}}[4, 0] : !llvm<"{ float*, float*, i64, [1 x i64], [1 x i64] }">
 
-func @dot(%arg0: memref<?xf32, offset: ?, strides: [1]>, %arg1: memref<?xf32, offset: ?, strides: [1]>, %arg2: memref<f32>) {
-  linalg.dot(%arg0, %arg1, %arg2) : memref<?xf32, offset: ?, strides: [1]>, memref<?xf32, offset: ?, strides: [1]>, memref<f32>
-  return
-}
-// CHECK-LABEL: func @dot
-// CHECK:   llvm.call @linalg_dot_viewsxf32_viewsxf32_viewf32(%{{.*}}) :
-// CHECK-SAME: !llvm<"float*">, !llvm<"float*">, !llvm.i64, !llvm.i64, !llvm.i64
-// CHECK-SAME: !llvm<"float*">, !llvm<"float*">, !llvm.i64, !llvm.i64, !llvm.i64
-// CHECK-SAME: !llvm<"float*">, !llvm<"float*">, !llvm.i64
-
 func @slice_with_range_and_index(%arg0: memref<?x?xf64, offset: ?, strides: [?, 1]>) {
   %c0 = constant 0 : index
   %c1 = constant 1 : index
   %R = linalg.range %c0:%c1:%c1 : !linalg.range
   loop.for %i0 = %c0 to %c1 step %c1 {
     %1 = linalg.slice %arg0[%i0, %R] : memref<?x?xf64, offset: ?, strides: [?, 1]>, index, !linalg.range, memref<?xf64, offset: ?, strides: [1]>
   }
   return
 }
 // CHECK-LABEL: func @slice_with_range_and_index
 // loop-body.
 //       CHECK:   llvm.mlir.undef : !llvm<"{ double*, double*, i64, [1 x i64], [1 x i64] }">
 //       CHECK:   llvm.extractvalue %{{.*}}[4, 0] : !llvm<"{ double*, double*, i64, [2 x i64], [2 x i64] }">
 //       CHECK:   llvm.extractvalue %{{.*}}[4, 1] : !llvm<"{ double*, double*, i64, [2 x i64], [2 x i64] }">
 //       CHECK:   llvm.extractvalue %{{.*}}[2] : !llvm<"{ double*, double*, i64, [2 x i64], [2 x i64] }">
 //       CHECK:   llvm.insertvalue %{{.*}}, %{{.*}}[0] : !llvm<"{ double*, double*, i64, [1 x i64], [1 x i64] }">
 //       CHECK:   llvm.insertvalue %{{.*}}[2] : !llvm<"{ double*, double*, i64, [1 x i64], [1 x i64] }">
 //       CHECK:   llvm.extractvalue %{{.*}}[0] : !llvm<"{ i64, i64, i64 }">
 //       CHECK:   llvm.extractvalue %{{.*}}[1] : !llvm<"{ i64, i64, i64 }">
 //       CHECK:   llvm.insertvalue %{{.*}}[3, 0] : !llvm<"{ double*, double*, i64, [1 x i64], [1 x i64] }">
 //       CHECK:   llvm.insertvalue %{{.*}}[4, 0] : !llvm<"{ double*, double*, i64, [1 x i64], [1 x i64] }">
 
-func @copy(%arg0: memref<?x?x?xf32, offset: ?, strides: [?, ?, 1]>, %arg1: memref<?x?x?xf32, offset: ?, strides: [?, ?, 1]>) {
-  linalg.copy(%arg0, %arg1) : memref<?x?x?xf32, offset: ?, strides: [?, ?, 1]>, memref<?x?x?xf32, offset: ?, strides: [?, ?, 1]>
-  return
-}
-// CHECK-LABEL: func @copy
-//       CHECK:   llvm.call @linalg_copy_viewsxsxsxf32_viewsxsxsxf32({{.*}}) :
-//  CHECK-SAME:   !llvm<"float*">, !llvm<"float*">, !llvm.i64, !llvm.i64, !llvm.i64, !llvm.i64, !llvm.i64, !llvm.i64, !llvm.i64
-//  CHECK-SAME:   !llvm<"float*">, !llvm<"float*">, !llvm.i64, !llvm.i64, !llvm.i64, !llvm.i64, !llvm.i64, !llvm.i64, !llvm.i64
-
 func @transpose(%arg0: memref<?x?x?xf32, offset: ?, strides: [?, ?, 1]>) {
   %0 = linalg.transpose %arg0 (i, j, k) -> (k, i, j) : memref<?x?x?xf32, offset: ?, strides: [?, ?, 1]>
   return
 }
 // CHECK-LABEL: func @transpose
 //       CHECK:   llvm.mlir.undef : !llvm<"{ float*, float*, i64, [3 x i64], [3 x i64] }">
 //       CHECK:   llvm.insertvalue {{.*}}[0] : !llvm<"{ float*, float*, i64, [3 x i64], [3 x i64] }">
 //       CHECK:    llvm.insertvalue {{.*}}[1] : !llvm<"{ float*, float*, i64, [3 x i64], [3 x i64] }">
 //       CHECK:    llvm.insertvalue {{.*}}[2] : !llvm<"{ float*, float*, i64, [3 x i64], [3 x i64] }">
 //       CHECK:   llvm.extractvalue {{.*}}[3, 0] : !llvm<"{ float*, float*, i64, [3 x i64], [3 x i64] }">
 //       CHECK:    llvm.insertvalue {{.*}}[3, 2] : !llvm<"{ float*, float*, i64, [3 x i64], [3 x i64] }">
 //       CHECK:   llvm.extractvalue {{.*}}[3, 1] : !llvm<"{ float*, float*, i64, [3 x i64], [3 x i64] }">
 //       CHECK:    llvm.insertvalue {{.*}}[3, 0] : !llvm<"{ float*, float*, i64, [3 x i64], [3 x i64] }">
 //       CHECK:   llvm.extractvalue {{.*}}[3, 2] : !llvm<"{ float*, float*, i64, [3 x i64], [3 x i64] }">
 //       CHECK:    llvm.insertvalue {{.*}}[3, 1] : !llvm<"{ float*, float*, i64, [3 x i64], [3 x i64] }">
 
-func @copy_transpose(%arg0: memref<?x?x?xf32, offset: ?, strides: [?, ?, 1]>, %arg1: memref<?x?x?xf32, offset: ?, strides: [?, ?, 1]>) {
-  linalg.copy(%arg0, %arg1) {inputPermutation = affine_map<(i, j, k) -> (i, k, j)>,
-                             outputPermutation = affine_map<(i, j, k) -> (k, j, i)>}
-    : memref<?x?x?xf32, offset: ?, strides: [?, ?, 1]>, memref<?x?x?xf32, offset: ?, strides: [?, ?, 1]>
-  return
-}
-// CHECK-LABEL: func @copy
-// Transpose input
-//         CHECK:   llvm.insertvalue {{.*}}[0] : !llvm<"{ float*, float*, i64, [3 x i64], [3 x i64] }">
-//         CHECK:    llvm.insertvalue {{.*}}[1] : !llvm<"{ float*, float*, i64, [3 x i64], [3 x i64] }">
-//         CHECK:    llvm.insertvalue {{.*}}[2] : !llvm<"{ float*, float*, i64, [3 x i64], [3 x i64] }">
-//         CHECK:   llvm.extractvalue {{.*}}[3, 0] : !llvm<"{ float*, float*, i64, [3 x i64], [3 x i64] }">
-//         CHECK:    llvm.insertvalue {{.*}}[3, 0] : !llvm<"{ float*, float*, i64, [3 x i64], [3 x i64] }">
-//         CHECK:   llvm.extractvalue {{.*}}[3, 1] : !llvm<"{ float*, float*, i64, [3 x i64], [3 x i64] }">
-//         CHECK:    llvm.insertvalue {{.*}}[3, 2] : !llvm<"{ float*, float*, i64, [3 x i64], [3 x i64] }">
-//         CHECK:   llvm.extractvalue {{.*}}[3, 2] : !llvm<"{ float*, float*, i64, [3 x i64], [3 x i64] }">
-//         CHECK:    llvm.insertvalue {{.*}}[3, 1] : !llvm<"{ float*, float*, i64, [3 x i64], [3 x i64] }">
-// Transpose output
-//         CHECK:   llvm.insertvalue {{.*}}[0] : !llvm<"{ float*, float*, i64, [3 x i64], [3 x i64] }">
-//         CHECK:    llvm.insertvalue {{.*}}[1] : !llvm<"{ float*, float*, i64, [3 x i64], [3 x i64] }">
-//         CHECK:    llvm.insertvalue {{.*}}[2] : !llvm<"{ float*, float*, i64, [3 x i64], [3 x i64] }">
-//         CHECK:   llvm.extractvalue {{.*}}[3, 0] : !llvm<"{ float*, float*, i64, [3 x i64], [3 x i64] }">
-//         CHECK:    llvm.insertvalue {{.*}}[3, 2] : !llvm<"{ float*, float*, i64, [3 x i64], [3 x i64] }">
-//         CHECK:   llvm.extractvalue {{.*}}[3, 1] : !llvm<"{ float*, float*, i64, [3 x i64], [3 x i64] }">
-//         CHECK:    llvm.insertvalue {{.*}}[3, 1] : !llvm<"{ float*, float*, i64, [3 x i64], [3 x i64] }">
-//         CHECK:   llvm.extractvalue {{.*}}[3, 2] : !llvm<"{ float*, float*, i64, [3 x i64], [3 x i64] }">
-//         CHECK:    llvm.insertvalue {{.*}}[3, 0] : !llvm<"{ float*, float*, i64, [3 x i64], [3 x i64] }">
-// Call external copy.
-//         CHECK:   llvm.call @linalg_copy_viewsxsxsxf32_viewsxsxsxf32
-
-#matmul_accesses = [
-  affine_map<(m, n, k) -> (m, k)>,
-  affine_map<(m, n, k) -> (k, n)>,
-  affine_map<(m, n, k) -> (m, n)>
-]
-#matmul_trait = {
-  args_in = 2,
-  args_out = 1,
-  iterator_types = ["parallel", "parallel", "reduction"],
-  indexing_maps = #matmul_accesses,
-  library_call = "external_outerproduct_matmul"
-}
-
-!vector_type_A = type vector<4xf32>
-!vector_type_B = type vector<4xf32>
-!vector_type_C = type vector<4x4xf32>
-
-!matrix_type_A = type memref<?x?x!vector_type_A>
-!matrix_type_B = type memref<?x?x!vector_type_B>
-!matrix_type_C = type memref<?x?x!vector_type_C>
-
-func @matmul_vec_impl(%A: !matrix_type_A, %B: !matrix_type_B, %C: !matrix_type_C) {
-  linalg.generic #matmul_trait %A, %B, %C {
-    ^bb0(%a: !vector_type_A, %b: !vector_type_B, %c: !vector_type_C):
-      %d = vector.outerproduct %a, %b, %c: !vector_type_A, !vector_type_B
-      linalg.yield %d: !vector_type_C
-  } : !matrix_type_A, !matrix_type_B, !matrix_type_C
-
-  return
-}
-// CHECK-LABEL: func @matmul_vec_impl(
-// CHECK:  llvm.call @external_outerproduct_matmul(%{{.*}}) :
-// CHECK-SAME: !llvm<"<4 x float>*">, !llvm<"<4 x float>*">, !llvm.i64, !llvm.i64, !llvm.i64, !llvm.i64, !llvm.i64
-// CHECK-SAME: !llvm<"<4 x float>*">, !llvm<"<4 x float>*">, !llvm.i64, !llvm.i64, !llvm.i64, !llvm.i64, !llvm.i64
-// CHECK-SAME: !llvm<"[4 x <4 x float>]*">, !llvm<"[4 x <4 x float>]*">, !llvm.i64, !llvm.i64, !llvm.i64, !llvm.i64, !llvm.i64
-
-// LLVM-LOOPS-LABEL: func @matmul_vec_impl(
-//  LLVM-LOOPS-SAME: %[[A:.*0]]: memref<?x?xvector<4xf32>>,
-//  LLVM-LOOPS-SAME: %[[B:.*1]]: memref<?x?xvector<4xf32>>,
-//  LLVM-LOOPS-SAME: %[[C:.*2]]: memref<?x?xvector<4x4xf32>>)
-// LLVM-LOOPS: %[[C0:.*]] = constant 0 : index
-// LLVM-LOOPS: %[[C1:.*]] = constant 1 : index
-// LLVM-LOOPS: %[[T0:.*]] = dim %[[A]], 0 : memref<?x?xvector<4xf32>>
-// LLVM-LOOPS: %[[T1:.*]] = dim %[[A]], 1 : memref<?x?xvector<4xf32>>
-// LLVM-LOOPS: %[[T2:.*]] = dim %[[B]], 1 : memref<?x?xvector<4xf32>>
-// LLVM-LOOPS: loop.for %[[I:.*]] = %[[C0]] to %[[T0]] step %[[C1]] {
-// LLVM-LOOPS: loop.for %[[J:.*]] = %[[C0]] to %[[T2]] step %[[C1]] {
-// LLVM-LOOPS: loop.for %[[K:.*]] = %[[C0]] to %[[T1]] step %[[C1]] {
-// LLVM-LOOPS:   %[[T3:.*]] = load %[[A]][%[[I]], %[[K]]] : memref<?x?xvector<4xf32>>
-// LLVM-LOOPS:   %[[T4:.*]] = load %[[B]][%[[K]], %[[J]]] : memref<?x?xvector<4xf32>>
-// LLVM-LOOPS:   %[[T5:.*]] = load %[[C]][%[[I]], %[[J]]] : memref<?x?xvector<4x4xf32>>
-// LLVM-LOOPS:   %[[T6:.*]] = vector.outerproduct %3, %4, %5 : vector<4xf32>, vector<4xf32>
-// LLVM-LOOPS:   store %[[T6]], %[[C]][%[[I]], %[[J]]] : memref<?x?xvector<4x4xf32>>
-
-#indexed_matmul_trait = {
-  args_in = 2,
-  args_out = 1,
-  iterator_types = ["parallel", "parallel", "reduction"],
-  indexing_maps = #matmul_accesses,
-  library_call = "external_indexed_outerproduct_matmul"
-}
-func @matmul_vec_indexed(%A: !matrix_type_A,
-                         %B: !matrix_type_B,
-                         %C: !matrix_type_C) {
-  linalg.indexed_generic #indexed_matmul_trait %A, %B, %C {
-    ^bb0(%i: index, %j: index, %k: index,
-         %a: !vector_type_A, %b: !vector_type_B, %c: !vector_type_C):
-      %d = vector.outerproduct %a, %b, %c: !vector_type_A, !vector_type_B
-      linalg.yield %d: !vector_type_C
-  } : !matrix_type_A, !matrix_type_B, !matrix_type_C
-  return
-}
-// CHECK-LABEL: func @matmul_vec_indexed(
-//   CHECK: %[[ZERO:.*]] = llvm.mlir.constant(0 : index) : !llvm.i64
-//   CHECK: llvm.call @external_indexed_outerproduct_matmul(%[[ZERO]], %[[ZERO]], %[[ZERO]], %{{.*}}) :
-// CHECK-SAME: !llvm<"<4 x float>*">, !llvm<"<4 x float>*">, !llvm.i64, !llvm.i64, !llvm.i64, !llvm.i64, !llvm.i64
-// CHECK-SAME: !llvm<"<4 x float>*">, !llvm<"<4 x float>*">, !llvm.i64, !llvm.i64, !llvm.i64, !llvm.i64, !llvm.i64
-// CHECK-SAME: !llvm<"[4 x <4 x float>]*">, !llvm<"[4 x <4 x float>]*">, !llvm.i64, !llvm.i64, !llvm.i64, !llvm.i64, !llvm.i64
-
 func @reshape_static(%arg0: memref<3x4x5xf32>) {
   // Reshapes that expand and collapse back a contiguous tensor with some 1's.
   %0 = linalg.reshape %arg0 [affine_map<(i, j, k, l, m) -> (i, j)>,
                              affine_map<(i, j, k, l, m) -> (k)>,
                              affine_map<(i, j, k, l, m) -> (l, m)>] :
     memref<3x4x5xf32> into memref<1x3x4x1x5xf32>
   %r0 = linalg.reshape %0 [affine_map<(i, j, k, l, m) -> (i, j)>,
                            affine_map<(i, j, k, l, m) -> (k)>,

mlir/test/Dialect/Linalg/standard.mlir

+// RUN: mlir-opt %s -convert-linalg-to-std | FileCheck %s
+
+// CHECK-DAG: #[[map0:.*]] = affine_map<(d0)[s0] -> (d0 + s0)>
+// CHECK-DAG: #[[map1:.*]] = affine_map<(d0, d1, d2)[s0, s1, s2] -> (d0 * s1 + s0 + d1 * s2 + d2)>
+// CHECK-DAG: #[[map2:.*]] = affine_map<(d0, d1, d2)[s0, s1, s2] -> (d0 * s1 + s0 + d2 * s2 + d1)>
+// CHECK-DAG: #[[map3:.*]] = affine_map<(d0, d1, d2) -> (d0, d2, d1)>
+// CHECK-DAG: #[[map4:.*]] = affine_map<(d0, d1, d2)[s0, s1, s2] -> (d2 * s1 + s0 + d1 * s2 + d0)>
+// CHECK-DAG: #[[map5:.*]] = affine_map<(d0, d1, d2) -> (d2, d1, d0)>
+
+func @dot(%arg0: memref<?xf32, offset: ?, strides: [1]>,
+          %arg1: memref<?xf32, offset: ?, strides: [1]>,
+          %arg2: memref<f32>) {
+  linalg.dot(%arg0, %arg1, %arg2) : memref<?xf32, offset: ?, strides: [1]>,
+                                    memref<?xf32, offset: ?, strides: [1]>,
+                                    memref<f32>
+  return
+}
+// CHECK-LABEL: func @dot(
+//  CHECK-SAME: %[[arg0:[a-zA-z0-9]*]]: memref<?xf32, #[[map0]]>,
+//  CHECK-SAME: %[[arg1:[a-zA-z0-9]*]]: memref<?xf32, #[[map0]]>,
+//  CHECK-SAME: %[[arg2:[a-zA-z0-9]*]]: memref<f32>) {
+//       CHECK:   %[[o0:.*]] = memref_cast %[[arg0]] :
+//  CHECK-SAME:     memref<?xf32, #[[map0]]> to memref<?xf32>
+//       CHECK:   %[[o1:.*]] = memref_cast %[[arg1]] :
+//  CHECK-SAME:     memref<?xf32, #[[map0]]> to memref<?xf32>
+//       CHECK:   call @linalg_dot_viewsxf32_viewsxf32_viewf32(
+//  CHECK-SAME:     %[[o0]], %[[o1]], %[[arg2]]) :
+//  CHECK-SAME:   memref<?xf32>, memref<?xf32>, memref<f32>
+
+func @copy(%arg0: memref<?x?x?xf32, offset: ?, strides: [?, ?, 1]>, %arg1: memref<?x?x?xf32, offset: ?, strides: [?, ?, 1]>) {
+  linalg.copy(%arg0, %arg1) : memref<?x?x?xf32, offset: ?, strides: [?, ?, 1]>, memref<?x?x?xf32, offset: ?, strides: [?, ?, 1]>
+  return
+}
+// CHECK-LABEL: func @copy(
+//  CHECK-SAME: %[[arg0:[a-zA-z0-9]*]]: memref<?x?x?xf32, #[[map1]]>,
+//  CHECK-SAME: %[[arg1:[a-zA-z0-9]*]]: memref<?x?x?xf32, #[[map1]]>) {
+//       CHECK:   %[[o0:.*]] = memref_cast %[[arg0]] :
+//  CHECK-SAME:     memref<?x?x?xf32, #[[map1]]> to memref<?x?x?xf32>
+//       CHECK:   %[[o1:.*]] = memref_cast %[[arg1]] :
+//  CHECK-SAME:     memref<?x?x?xf32, #[[map1]]> to memref<?x?x?xf32>
+//       CHECK:   call @linalg_copy_viewsxsxsxf32_viewsxsxsxf32(%[[o0]], %[[o1]]) :
+//  CHECK-SAME:   memref<?x?x?xf32>, memref<?x?x?xf32>
+
+func @copy_transpose(%arg0: memref<?x?x?xf32, offset: ?, strides: [?, ?, 1]>, %arg1: memref<?x?x?xf32, offset: ?, strides: [?, ?, 1]>) {
+  linalg.copy(%arg0, %arg1) {inputPermutation = affine_map<(i, j, k) -> (i, k, j)>,
+                             outputPermutation = affine_map<(i, j, k) -> (k, j, i)>}
+    : memref<?x?x?xf32, offset: ?, strides: [?, ?, 1]>, memref<?x?x?xf32, offset: ?, strides: [?, ?, 1]>
+  return
+}
+// CHECK-LABEL: func @copy_transpose(
+//  CHECK-SAME: %[[arg0:[a-zA-z0-9]*]]: memref<?x?x?xf32, #[[map1]]>,
+//  CHECK-SAME: %[[arg1:[a-zA-z0-9]*]]: memref<?x?x?xf32, #[[map1]]>) {
+//       CHECK:   %[[t0:.*]] = linalg.transpose %[[arg0]]
+//  CHECK-SAME:     (d0, d1, d2) -> (d0, d2, d1) : memref<?x?x?xf32, #[[map1]]>
+//       CHECK:   %[[t1:.*]] = linalg.transpose %[[arg1]]
+//  CHECK-SAME:     (d0, d1, d2) -> (d2, d1, d0) : memref<?x?x?xf32, #[[map1]]>
+//       CHECK:   %[[o0:.*]] = memref_cast %[[t0]] :
+//  CHECK-SAME:     memref<?x?x?xf32, #[[map2]]> to memref<?x?x?xf32>
+//       CHECK:   %[[o1:.*]] = memref_cast %[[t1]] :
+//  CHECK-SAME:     memref<?x?x?xf32, #[[map4]]> to memref<?x?x?xf32>
+//       CHECK:   call @linalg_copy_viewsxsxsxf32_viewsxsxsxf32(%[[o0]], %[[o1]]) :
+//  CHECK-SAME:   memref<?x?x?xf32>, memref<?x?x?xf32>
+
+#matmul_accesses = [
+  affine_map<(m, n, k) -> (m, k)>,
+  affine_map<(m, n, k) -> (k, n)>,
+  affine_map<(m, n, k) -> (m, n)>
+]
+#matmul_trait = {
+  args_in = 2,
+  args_out = 1,
+  iterator_types = ["parallel", "parallel", "reduction"],
+  indexing_maps = #matmul_accesses,
+  library_call = "external_outerproduct_matmul"
+}
+
+!vector_type_A = type vector<4xf32>
+!vector_type_B = type vector<4xf32>
+!vector_type_C = type vector<4x4xf32>
+
+!matrix_type_A = type memref<?x?x!vector_type_A>
+!matrix_type_B = type memref<?x?x!vector_type_B>
+!matrix_type_C = type memref<?x?x!vector_type_C>
+
+func @matmul_vec_impl(%A: !matrix_type_A, %B: !matrix_type_B, %C: !matrix_type_C) {
+  linalg.generic #matmul_trait %A, %B, %C {
+    ^bb0(%a: !vector_type_A, %b: !vector_type_B, %c: !vector_type_C):
+      %d = vector.outerproduct %a, %b, %c: !vector_type_A, !vector_type_B
+      linalg.yield %d: !vector_type_C
+  } : !matrix_type_A, !matrix_type_B, !matrix_type_C
+
+  return
+}
+// CHECK-LABEL: func @matmul_vec_impl(
+// CHECK:  call @external_outerproduct_matmul(%{{.*}}) :
+
+#indexed_matmul_trait = {
+  args_in = 2,
+  args_out = 1,
+  iterator_types = ["parallel", "parallel", "reduction"],
+  indexing_maps = #matmul_accesses,
+  library_call = "external_indexed_outerproduct_matmul"
+}
+func @matmul_vec_indexed(%A: !matrix_type_A,
+                         %B: !matrix_type_B,
+                         %C: !matrix_type_C) {
+  linalg.indexed_generic #indexed_matmul_trait %A, %B, %C {
+    ^bb0(%i: index, %j: index, %k: index,
+         %a: !vector_type_A, %b: !vector_type_B, %c: !vector_type_C):
+      %d = vector.outerproduct %a, %b, %c: !vector_type_A, !vector_type_B
+      linalg.yield %d: !vector_type_C
+  } : !matrix_type_A, !matrix_type_B, !matrix_type_C
+  return
+}
+// CHECK-LABEL: func @matmul_vec_indexed(
+//   CHECK: %[[ZERO:.*]] = constant 0 : index
+//   CHECK: call @external_indexed_outerproduct_matmul(%[[ZERO]], %[[ZERO]], %[[ZERO]], %{{.*}})

mlir/test/mlir-cpu-runner/linalg_integration_test.mlir

-// RUN: mlir-opt %s -convert-linalg-to-llvm \
+// RUN: mlir-opt %s -convert-linalg-to-std -convert-linalg-to-llvm \
 // RUN: | mlir-cpu-runner -e dot -entry-point-result=f32 -shared-libs=%linalg_test_lib_dir/libmlir_test_cblas%shlibext,%linalg_test_lib_dir/libmlir_test_cblas_interface%shlibext \
 // RUN: | FileCheck %s
 
-// RUN: mlir-opt %s -convert-linalg-to-loops -convert-linalg-to-llvm \
+// RUN: mlir-opt %s -convert-linalg-to-loops -convert-linalg-to-std -convert-linalg-to-llvm \
 // RUN: | mlir-cpu-runner -e dot -entry-point-result=f32 -shared-libs=%linalg_test_lib_dir/libmlir_test_cblas%shlibext,%linalg_test_lib_dir/libmlir_test_cblas_interface%shlibext \
 // RUN: | FileCheck %s
 
-// RUN: mlir-opt %s -convert-linalg-to-llvm \
+// RUN: mlir-opt %s -convert-linalg-to-std -convert-linalg-to-llvm \
 // RUN: | mlir-cpu-runner -e matmul -entry-point-result=f32 -shared-libs=%linalg_test_lib_dir/libmlir_test_cblas%shlibext,%linalg_test_lib_dir/libmlir_test_cblas_interface%shlibext \
 // RUN: | FileCheck %s
 
-// RUN: mlir-opt %s -convert-linalg-to-loops -convert-linalg-to-llvm \
+// RUN: mlir-opt %s -convert-linalg-to-loops -convert-linalg-to-std -convert-linalg-to-llvm \
 // RUN: | mlir-cpu-runner -e matmul -entry-point-result=f32 -shared-libs=%linalg_test_lib_dir/libmlir_test_cblas%shlibext,%linalg_test_lib_dir/libmlir_test_cblas_interface%shlibext \
 // RUN: | FileCheck %s
 
-// RUN: mlir-opt %s -linalg-tile="linalg-tile-sizes=2,3,4" -linalg-promote-subviews -convert-linalg-to-loops -convert-linalg-to-llvm \
+// RUN: mlir-opt %s -linalg-tile="linalg-tile-sizes=2,3,4" -linalg-promote-subviews -convert-linalg-to-loops -convert-linalg-to-std -convert-linalg-to-llvm \
 // RUN: | mlir-cpu-runner -e matmul -entry-point-result=f32 -shared-libs=%linalg_test_lib_dir/libmlir_test_cblas%shlibext,%linalg_test_lib_dir/libmlir_test_cblas_interface%shlibext \
 // RUN: | FileCheck %s
 
-// RUN: mlir-opt %s -linalg-tile="linalg-tile-sizes=2,3,4" -linalg-promote-subviews -convert-linalg-to-llvm \
+// RUN: mlir-opt %s -linalg-tile="linalg-tile-sizes=2,3,4" -linalg-promote-subviews -convert-linalg-to-std -convert-linalg-to-llvm \
 // RUN: | mlir-cpu-runner -e matmul -entry-point-result=f32 -shared-libs=%linalg_test_lib_dir/libmlir_test_cblas%shlibext,%linalg_test_lib_dir/libmlir_test_cblas_interface%shlibext \
 // RUN: | FileCheck %s
 
 #strided1D = affine_map<(d0) -> (d0)>
 #strided2D = affine_map<(d0, d1)[s0] -> (d0 * s0 + d1)>
 
 // Creates and returns a 1-D buffer of size %s filled with the value %f
 func @alloc_filled_f32(%s : index, %f : f32) -> memref<?xi8> {