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[NFC][flang][OpenMP] Extract target region utils to map or clone outside values #155754

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[NFC][flang][OpenMP] Extract target region utils to map or clone outside values #155754

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29 changes: 29 additions & 0 deletions flang/include/flang/Utils/OpenMP.h
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Original file line number Diff line number Diff line change
Expand Up @@ -11,6 +11,10 @@

#include "mlir/Dialect/OpenMP/OpenMPDialect.h"

namespace fir {
class FirOpBuilder;
} // namespace fir

namespace Fortran::utils::openmp {
// TODO We can probably move the stuff inside `Support/OpenMP-utils.h/.cpp` here
// as well.
Expand All @@ -28,6 +32,31 @@ mlir::omp::MapInfoOp createMapInfoOp(mlir::OpBuilder &builder,
uint64_t mapType, mlir::omp::VariableCaptureKind mapCaptureType,
mlir::Type retTy, bool partialMap = false,
mlir::FlatSymbolRefAttr mapperId = mlir::FlatSymbolRefAttr());

/// For an mlir value that does not have storage, allocate temporary storage
/// (outside the target region), store the value in that storage, and map the
/// storage to the target region.
///
/// \param firOpBuilder - Operation builder.
/// \param targetOp - Target op to which the temporary value is mapped.
/// \param val - Temp value that should be mapped to the target region.
/// \param name - A string used to identify the created `omp.map.info`
/// op.
///
/// \returns The loaded mapped value inside the target region.
mlir::Value mapTemporaryValue(fir::FirOpBuilder &firOpBuilder,
mlir::omp::TargetOp targetOp, mlir::Value val, llvm::StringRef name);

/// For values used inside a target region but defined outside, either clone
/// these value inside the target region or map them to the region. This
/// function tries firts to clone values (if they are defined by
/// memory-effect-free ops, otherwise, the values are mapped.
///
/// \param firOpBuilder - Operation builder.
/// \param targetOp - The target that needs to be extended by clones and/or
/// maps.
void cloneOrMapRegionOutsiders(
fir::FirOpBuilder &firOpBuilder, mlir::omp::TargetOp targetOp);
} // namespace Fortran::utils::openmp

#endif // FORTRAN_UTILS_OPENMP_H_
99 changes: 1 addition & 98 deletions flang/lib/Lower/OpenMP/OpenMP.cpp
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Expand Up @@ -1431,104 +1431,7 @@ static void genBodyOfTargetOp(
// If so, then either clone them as well if they are MemoryEffectFree, or else
// copy them to a new temporary and add them to the map and block_argument
// lists and replace their uses with the new temporary.
llvm::SetVector<mlir::Value> valuesDefinedAbove;
mlir::getUsedValuesDefinedAbove(region, valuesDefinedAbove);
while (!valuesDefinedAbove.empty()) {
for (mlir::Value val : valuesDefinedAbove) {
mlir::Operation *valOp = val.getDefiningOp();

// NOTE: We skip BoxDimsOp's as the lesser of two evils is to map the
// indices separately, as the alternative is to eventually map the Box,
// which comes with a fairly large overhead comparatively. We could be
// more robust about this and check using a BackwardsSlice to see if we
// run the risk of mapping a box.
if (valOp && mlir::isMemoryEffectFree(valOp) &&
!mlir::isa<fir::BoxDimsOp>(valOp)) {
mlir::Operation *clonedOp = valOp->clone();
entryBlock->push_front(clonedOp);

auto replace = [entryBlock](mlir::OpOperand &use) {
return use.getOwner()->getBlock() == entryBlock;
};

valOp->getResults().replaceUsesWithIf(clonedOp->getResults(), replace);
valOp->replaceUsesWithIf(clonedOp, replace);
} else {
auto savedIP = firOpBuilder.getInsertionPoint();

if (valOp)
firOpBuilder.setInsertionPointAfter(valOp);
else
// This means val is a block argument
firOpBuilder.setInsertionPoint(targetOp);

auto copyVal =
firOpBuilder.createTemporary(val.getLoc(), val.getType());
firOpBuilder.createStoreWithConvert(copyVal.getLoc(), val, copyVal);

fir::factory::AddrAndBoundsInfo info =
fir::factory::getDataOperandBaseAddr(
firOpBuilder, val, /*isOptional=*/false, val.getLoc());
llvm::SmallVector<mlir::Value> bounds =
fir::factory::genImplicitBoundsOps<mlir::omp::MapBoundsOp,
mlir::omp::MapBoundsType>(
firOpBuilder, info,
hlfir::translateToExtendedValue(val.getLoc(), firOpBuilder,
hlfir::Entity{val})
.first,
/*dataExvIsAssumedSize=*/false, val.getLoc());

std::stringstream name;
firOpBuilder.setInsertionPoint(targetOp);

llvm::omp::OpenMPOffloadMappingFlags mapFlag =
llvm::omp::OpenMPOffloadMappingFlags::OMP_MAP_IMPLICIT;
mlir::omp::VariableCaptureKind captureKind =
mlir::omp::VariableCaptureKind::ByRef;

mlir::Type eleType = copyVal.getType();
if (auto refType =
mlir::dyn_cast<fir::ReferenceType>(copyVal.getType()))
eleType = refType.getElementType();

if (fir::isa_trivial(eleType) || fir::isa_char(eleType)) {
captureKind = mlir::omp::VariableCaptureKind::ByCopy;
} else if (!fir::isa_builtin_cptr_type(eleType)) {
mapFlag |= llvm::omp::OpenMPOffloadMappingFlags::OMP_MAP_TO;
}

mlir::Value mapOp = createMapInfoOp(
firOpBuilder, copyVal.getLoc(), copyVal,
/*varPtrPtr=*/mlir::Value{}, name.str(), bounds,
/*members=*/llvm::SmallVector<mlir::Value>{},
/*membersIndex=*/mlir::ArrayAttr{},
static_cast<
std::underlying_type_t<llvm::omp::OpenMPOffloadMappingFlags>>(
mapFlag),
captureKind, copyVal.getType());

// Get the index of the first non-map argument before modifying mapVars,
// then append an element to mapVars and an associated entry block
// argument at that index.
unsigned insertIndex =
argIface.getMapBlockArgsStart() + argIface.numMapBlockArgs();
targetOp.getMapVarsMutable().append(mapOp);
mlir::Value clonedValArg = region.insertArgument(
insertIndex, copyVal.getType(), copyVal.getLoc());

firOpBuilder.setInsertionPointToStart(entryBlock);
auto loadOp = fir::LoadOp::create(firOpBuilder, clonedValArg.getLoc(),
clonedValArg);
val.replaceUsesWithIf(loadOp->getResult(0),
[entryBlock](mlir::OpOperand &use) {
return use.getOwner()->getBlock() == entryBlock;
});
firOpBuilder.setInsertionPoint(entryBlock, savedIP);
}
}
valuesDefinedAbove.clear();
mlir::getUsedValuesDefinedAbove(region, valuesDefinedAbove);
}
cloneOrMapRegionOutsiders(firOpBuilder, targetOp);

// Insert dummy instruction to remember the insertion position. The
// marker will be deleted since there are not uses.
Expand Down
113 changes: 113 additions & 0 deletions flang/lib/Utils/OpenMP.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -8,10 +8,14 @@

#include "flang/Utils/OpenMP.h"

#include "flang/Lower/ConvertExprToHLFIR.h"
#include "flang/Optimizer/Builder/DirectivesCommon.h"
#include "flang/Optimizer/Builder/FIRBuilder.h"
#include "flang/Optimizer/Dialect/FIROps.h"
#include "flang/Optimizer/Dialect/FIRType.h"

#include "mlir/Dialect/OpenMP/OpenMPDialect.h"
#include "mlir/Transforms/RegionUtils.h"

namespace Fortran::utils::openmp {
mlir::omp::MapInfoOp createMapInfoOp(mlir::OpBuilder &builder,
Expand Down Expand Up @@ -44,4 +48,113 @@ mlir::omp::MapInfoOp createMapInfoOp(mlir::OpBuilder &builder,
builder.getStringAttr(name), builder.getBoolAttr(partialMap));
return op;
}

mlir::Value mapTemporaryValue(fir::FirOpBuilder &firOpBuilder,
mlir::omp::TargetOp targetOp, mlir::Value val, llvm::StringRef name) {
mlir::OpBuilder::InsertionGuard guard(firOpBuilder);
mlir::Operation *valOp = val.getDefiningOp();

if (valOp)
firOpBuilder.setInsertionPointAfter(valOp);
else
// This means val is a block argument
firOpBuilder.setInsertionPoint(targetOp);

auto copyVal = firOpBuilder.createTemporary(val.getLoc(), val.getType());
firOpBuilder.createStoreWithConvert(copyVal.getLoc(), val, copyVal);

fir::factory::AddrAndBoundsInfo info = fir::factory::getDataOperandBaseAddr(
firOpBuilder, val, /*isOptional=*/false, val.getLoc());
llvm::SmallVector<mlir::Value> bounds =
fir::factory::genImplicitBoundsOps<mlir::omp::MapBoundsOp,
mlir::omp::MapBoundsType>(firOpBuilder, info,
hlfir::translateToExtendedValue(
val.getLoc(), firOpBuilder, hlfir::Entity{val})
.first,
/*dataExvIsAssumedSize=*/false, val.getLoc());

firOpBuilder.setInsertionPoint(targetOp);

llvm::omp::OpenMPOffloadMappingFlags mapFlag =
llvm::omp::OpenMPOffloadMappingFlags::OMP_MAP_IMPLICIT;
mlir::omp::VariableCaptureKind captureKind =
mlir::omp::VariableCaptureKind::ByRef;

mlir::Type eleType = copyVal.getType();
if (auto refType = mlir::dyn_cast<fir::ReferenceType>(copyVal.getType())) {
eleType = refType.getElementType();
}

if (fir::isa_trivial(eleType) || fir::isa_char(eleType)) {
captureKind = mlir::omp::VariableCaptureKind::ByCopy;
} else if (!fir::isa_builtin_cptr_type(eleType)) {
mapFlag |= llvm::omp::OpenMPOffloadMappingFlags::OMP_MAP_TO;
}

mlir::Value mapOp = createMapInfoOp(firOpBuilder, copyVal.getLoc(), copyVal,
/*varPtrPtr=*/mlir::Value{}, name.str(), bounds,
/*members=*/llvm::SmallVector<mlir::Value>{},
/*membersIndex=*/mlir::ArrayAttr{},
static_cast<std::underlying_type_t<llvm::omp::OpenMPOffloadMappingFlags>>(
mapFlag),
captureKind, copyVal.getType());

auto argIface = llvm::cast<mlir::omp::BlockArgOpenMPOpInterface>(*targetOp);
mlir::Region &region = targetOp.getRegion();

// Get the index of the first non-map argument before modifying mapVars,
// then append an element to mapVars and an associated entry block
// argument at that index.
unsigned insertIndex =
argIface.getMapBlockArgsStart() + argIface.numMapBlockArgs();
targetOp.getMapVarsMutable().append(mapOp);
mlir::Value clonedValArg =
region.insertArgument(insertIndex, copyVal.getType(), copyVal.getLoc());

mlir::Block *entryBlock = &region.getBlocks().front();
firOpBuilder.setInsertionPointToStart(entryBlock);
auto loadOp =
firOpBuilder.create<fir::LoadOp>(clonedValArg.getLoc(), clonedValArg);
return loadOp.getResult();
}

void cloneOrMapRegionOutsiders(
fir::FirOpBuilder &firOpBuilder, mlir::omp::TargetOp targetOp) {
mlir::Region &region = targetOp.getRegion();
mlir::Block *entryBlock = &region.getBlocks().front();

llvm::SetVector<mlir::Value> valuesDefinedAbove;
mlir::getUsedValuesDefinedAbove(region, valuesDefinedAbove);
while (!valuesDefinedAbove.empty()) {
for (mlir::Value val : valuesDefinedAbove) {
mlir::Operation *valOp = val.getDefiningOp();

// NOTE: We skip BoxDimsOp's as the lesser of two evils is to map the
// indices separately, as the alternative is to eventually map the Box,
// which comes with a fairly large overhead comparatively. We could be
// more robust about this and check using a BackwardsSlice to see if we
// run the risk of mapping a box.
if (valOp && mlir::isMemoryEffectFree(valOp) &&
!mlir::isa<fir::BoxDimsOp>(valOp)) {
mlir::Operation *clonedOp = valOp->clone();
entryBlock->push_front(clonedOp);

auto replace = [entryBlock](mlir::OpOperand &use) {
return use.getOwner()->getBlock() == entryBlock;
};

valOp->getResults().replaceUsesWithIf(clonedOp->getResults(), replace);
valOp->replaceUsesWithIf(clonedOp, replace);
} else {
mlir::Value mappedTemp = mapTemporaryValue(firOpBuilder, targetOp, val,
/*name=*/{});
val.replaceUsesWithIf(mappedTemp, [entryBlock](mlir::OpOperand &use) {
return use.getOwner()->getBlock() == entryBlock;
});
}
}
valuesDefinedAbove.clear();
mlir::getUsedValuesDefinedAbove(region, valuesDefinedAbove);
}
}
} // namespace Fortran::utils::openmp