//===- ViewLikeInterface.cpp - View-like operations in MLIR ---------------===//
//
// 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/Interfaces/ViewLikeInterface.h"

using namespace mlir;

//===----------------------------------------------------------------------===//
// ViewLike Interfaces
//===----------------------------------------------------------------------===//

/// Include the definitions of the loop-like interfaces.
#include "mlir/Interfaces/ViewLikeInterface.cpp.inc"

LogicalResult mlir::verifyListOfOperandsOrIntegers(
    Operation *op, StringRef name, unsigned numElements, ArrayAttr attr,
    ValueRange values, llvm::function_ref<bool(int64_t)> isDynamic) {
  /// Check static and dynamic offsets/sizes/strides does not overflow type.
  if (attr.size() != numElements)
    return op->emitError("expected ")
           << numElements << " " << name << " values";
  unsigned expectedNumDynamicEntries =
      llvm::count_if(attr.getValue(), [&](Attribute attr) {
        return isDynamic(attr.cast<IntegerAttr>().getInt());
      });
  if (values.size() != expectedNumDynamicEntries)
    return op->emitError("expected ")
           << expectedNumDynamicEntries << " dynamic " << name << " values";
  return success();
}

LogicalResult
mlir::detail::verifyOffsetSizeAndStrideOp(OffsetSizeAndStrideOpInterface op) {
  std::array<unsigned, 3> maxRanks = op.getArrayAttrMaxRanks();
  // Offsets can come in 2 flavors:
  //   1. Either single entry (when maxRanks == 1).
  //   2. Or as an array whose rank must match that of the mixed sizes.
  // So that the result type is well-formed.
  if (!(op.getMixedOffsets().size() == 1 && maxRanks[0] == 1) && // NOLINT
      op.getMixedOffsets().size() != op.getMixedSizes().size())
    return op->emitError(
               "expected mixed offsets rank to match mixed sizes rank (")
           << op.getMixedOffsets().size() << " vs " << op.getMixedSizes().size()
           << ") so the rank of the result type is well-formed.";
  // Ranks of mixed sizes and strides must always match so the result type is
  // well-formed.
  if (op.getMixedSizes().size() != op.getMixedStrides().size())
    return op->emitError(
               "expected mixed sizes rank to match mixed strides rank (")
           << op.getMixedSizes().size() << " vs " << op.getMixedStrides().size()
           << ") so the rank of the result type is well-formed.";

  if (failed(verifyListOfOperandsOrIntegers(
          op, "offset", maxRanks[0], op.static_offsets(), op.offsets(),
          ShapedType::isDynamicStrideOrOffset)))
    return failure();
  if (failed(verifyListOfOperandsOrIntegers(op, "size", maxRanks[1],
                                            op.static_sizes(), op.sizes(),
                                            ShapedType::isDynamic)))
    return failure();
  if (failed(verifyListOfOperandsOrIntegers(
          op, "stride", maxRanks[2], op.static_strides(), op.strides(),
          ShapedType::isDynamicStrideOrOffset)))
    return failure();
  return success();
}

void mlir::printDynamicIndexList(OpAsmPrinter &printer, Operation *op,
                                 OperandRange values, ArrayAttr integers,
                                 int64_t dynVal) {
  printer << '[';
  if (integers.empty()) {
    printer << "]";
    return;
  }
  unsigned idx = 0;
  llvm::interleaveComma(integers, printer, [&](Attribute a) {
    int64_t val = a.cast<IntegerAttr>().getInt();
    if (val == dynVal)
      printer << values[idx++];
    else
      printer << val;
  });
  printer << ']';
}

ParseResult mlir::parseDynamicIndexList(
    OpAsmParser &parser,
    SmallVectorImpl<OpAsmParser::UnresolvedOperand> &values,
    ArrayAttr &integers, int64_t dynVal) {
  if (failed(parser.parseLSquare()))
    return failure();
  // 0-D.
  if (succeeded(parser.parseOptionalRSquare())) {
    integers = parser.getBuilder().getArrayAttr({});
    return success();
  }

  SmallVector<int64_t, 4> attrVals;
  while (true) {
    OpAsmParser::UnresolvedOperand operand;
    auto res = parser.parseOptionalOperand(operand);
    if (res.has_value() && succeeded(res.value())) {
      values.push_back(operand);
      attrVals.push_back(dynVal);
    } else {
      IntegerAttr attr;
      if (failed(parser.parseAttribute<IntegerAttr>(attr)))
        return parser.emitError(parser.getNameLoc())
               << "expected SSA value or integer";
      attrVals.push_back(attr.getInt());
    }

    if (succeeded(parser.parseOptionalComma()))
      continue;
    if (failed(parser.parseRSquare()))
      return failure();
    break;
  }
  integers = parser.getBuilder().getI64ArrayAttr(attrVals);
  return success();
}

bool mlir::detail::sameOffsetsSizesAndStrides(
    OffsetSizeAndStrideOpInterface a, OffsetSizeAndStrideOpInterface b,
    llvm::function_ref<bool(OpFoldResult, OpFoldResult)> cmp) {
  if (a.static_offsets().size() != b.static_offsets().size())
    return false;
  if (a.static_sizes().size() != b.static_sizes().size())
    return false;
  if (a.static_strides().size() != b.static_strides().size())
    return false;
  for (auto it : llvm::zip(a.getMixedOffsets(), b.getMixedOffsets()))
    if (!cmp(std::get<0>(it), std::get<1>(it)))
      return false;
  for (auto it : llvm::zip(a.getMixedSizes(), b.getMixedSizes()))
    if (!cmp(std::get<0>(it), std::get<1>(it)))
      return false;
  for (auto it : llvm::zip(a.getMixedStrides(), b.getMixedStrides()))
    if (!cmp(std::get<0>(it), std::get<1>(it)))
      return false;
  return true;
}

SmallVector<OpFoldResult, 4>
mlir::getMixedValues(ArrayAttr staticValues, ValueRange dynamicValues,
                     const int64_t dynamicValueIndicator) {
  SmallVector<OpFoldResult, 4> res;
  res.reserve(staticValues.size());
  unsigned numDynamic = 0;
  unsigned count = static_cast<unsigned>(staticValues.size());
  for (unsigned idx = 0; idx < count; ++idx) {
    APInt value = staticValues[idx].cast<IntegerAttr>().getValue();
    res.push_back(value.getSExtValue() == dynamicValueIndicator
                      ? OpFoldResult{dynamicValues[numDynamic++]}
                      : OpFoldResult{staticValues[idx]});
  }
  return res;
}

SmallVector<OpFoldResult, 4>
mlir::getMixedStridesOrOffsets(ArrayAttr staticValues,
                               ValueRange dynamicValues) {
  return getMixedValues(staticValues, dynamicValues,
                        ShapedType::kDynamicStrideOrOffset);
}

SmallVector<OpFoldResult, 4> mlir::getMixedSizes(ArrayAttr staticValues,
                                                 ValueRange dynamicValues) {
  return getMixedValues(staticValues, dynamicValues, ShapedType::kDynamicSize);
}

std::pair<ArrayAttr, SmallVector<Value>>
mlir::decomposeMixedValues(Builder &b,
                           const SmallVectorImpl<OpFoldResult> &mixedValues,
                           const int64_t dynamicValueIndicator) {
  SmallVector<int64_t> staticValues;
  SmallVector<Value> dynamicValues;
  for (const auto &it : mixedValues) {
    if (it.is<Attribute>()) {
      staticValues.push_back(it.get<Attribute>().cast<IntegerAttr>().getInt());
    } else {
      staticValues.push_back(dynamicValueIndicator);
      dynamicValues.push_back(it.get<Value>());
    }
  }
  return {b.getI64ArrayAttr(staticValues), dynamicValues};
}

std::pair<ArrayAttr, SmallVector<Value>> mlir::decomposeMixedStridesOrOffsets(
    OpBuilder &b, const SmallVectorImpl<OpFoldResult> &mixedValues) {
  return decomposeMixedValues(b, mixedValues,
                              ShapedType::kDynamicStrideOrOffset);
}

std::pair<ArrayAttr, SmallVector<Value>>
mlir::decomposeMixedSizes(OpBuilder &b,
                          const SmallVectorImpl<OpFoldResult> &mixedValues) {
  return decomposeMixedValues(b, mixedValues, ShapedType::kDynamicSize);
}