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Sep 28, 2023
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[flang][openacc] Support assumed shape arrays in reduction #67610

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4 changes: 4 additions & 0 deletions flang/include/flang/Optimizer/Builder/HLFIRTools.h
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Expand Up @@ -418,6 +418,10 @@ hlfir::ElementalOp cloneToElementalOp(mlir::Location loc,
/// would be incorrect.
bool elementalOpMustProduceTemp(hlfir::ElementalOp elemental);

std::pair<hlfir::Entity, mlir::Value>
createTempFromMold(mlir::Location loc, fir::FirOpBuilder &builder,
hlfir::Entity mold);

} // namespace hlfir

#endif // FORTRAN_OPTIMIZER_BUILDER_HLFIRTOOLS_H
44 changes: 39 additions & 5 deletions flang/lib/Lower/OpenACC.cpp
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Expand Up @@ -22,6 +22,7 @@
#include "flang/Optimizer/Builder/BoxValue.h"
#include "flang/Optimizer/Builder/Complex.h"
#include "flang/Optimizer/Builder/FIRBuilder.h"
#include "flang/Optimizer/Builder/HLFIRTools.h"
#include "flang/Optimizer/Builder/IntrinsicCall.h"
#include "flang/Optimizer/Builder/Todo.h"
#include "flang/Parser/parse-tree.h"
Expand Down Expand Up @@ -704,6 +705,9 @@ static mlir::Value getReductionInitValue(fir::FirOpBuilder &builder,
if (auto seqTy = mlir::dyn_cast<fir::SequenceType>(ty))
return getReductionInitValue(builder, loc, seqTy.getEleTy(), op);

if (auto boxTy = mlir::dyn_cast<fir::BaseBoxType>(ty))
return getReductionInitValue(builder, loc, boxTy.getEleTy(), op);

llvm::report_fatal_error("Unsupported OpenACC reduction type");
}

Expand Down Expand Up @@ -749,6 +753,14 @@ static mlir::Value genReductionInitRegion(fir::FirOpBuilder &builder,
builder.setInsertionPointAfter(loops[0]);
return declareOp.getBase();
}
} else if (auto boxTy = mlir::dyn_cast_or_null<fir::BaseBoxType>(ty)) {
if (!mlir::isa<fir::SequenceType>(boxTy.getEleTy()))
TODO(loc, "Unsupported boxed type for reduction");
// Create the private copy from the initial fir.box.
hlfir::Entity source = hlfir::Entity{builder.getBlock()->getArgument(0)};
auto [temp, cleanup] = hlfir::createTempFromMold(loc, builder, source);
builder.create<hlfir::AssignOp>(loc, initValue, temp);
return temp;
}
llvm::report_fatal_error("Unsupported OpenACC reduction type");
}
Expand Down Expand Up @@ -850,8 +862,8 @@ static void genCombiner(fir::FirOpBuilder &builder, mlir::Location loc,
ty = fir::unwrapRefType(ty);

if (auto seqTy = mlir::dyn_cast<fir::SequenceType>(ty)) {
if (seqTy.hasDynamicExtents())
TODO(loc, "OpenACC reduction on array with dynamic extents");
assert(!seqTy.hasDynamicExtents() &&
"Assumed shaped array should be boxed for reduction");
mlir::Type idxTy = builder.getIndexType();
mlir::Type refTy = fir::ReferenceType::get(seqTy.getEleTy());

Expand All @@ -875,6 +887,29 @@ static void genCombiner(fir::FirOpBuilder &builder, mlir::Location loc,
genScalarCombiner(builder, loc, op, seqTy.getEleTy(), load1, load2);
builder.create<fir::StoreOp>(loc, res, addr1);
builder.setInsertionPointAfter(loops[0]);
} else if (auto boxTy = mlir::dyn_cast<fir::BaseBoxType>(ty)) {
fir::SequenceType seqTy =
mlir::dyn_cast_or_null<fir::SequenceType>(boxTy.getEleTy());
if (!seqTy)
TODO(loc, "Unsupported boxed type in OpenACC reduction");
hlfir::Entity left = hlfir::Entity{value1};
hlfir::Entity right = hlfir::Entity{value2};
auto shape = hlfir::genShape(loc, builder, left);
llvm::SmallVector<mlir::Value, 1> typeParams;
auto genKernel = [&builder, &loc, op, seqTy, &left, &right](
mlir::Location l, fir::FirOpBuilder &b,
mlir::ValueRange oneBasedIndices) -> hlfir::Entity {
auto leftElement = hlfir::getElementAt(l, b, left, oneBasedIndices);
auto rightElement = hlfir::getElementAt(l, b, right, oneBasedIndices);
auto leftVal = hlfir::loadTrivialScalar(l, b, leftElement);
auto rightVal = hlfir::loadTrivialScalar(l, b, rightElement);
return hlfir::Entity{genScalarCombiner(builder, loc, op, seqTy.getEleTy(),
leftVal, rightVal)};
};
mlir::Value elemental = hlfir::genElementalOp(
loc, builder, seqTy.getEleTy(), shape, typeParams, genKernel,
/*isUnordered=*/true);
builder.create<hlfir::AssignOp>(loc, elemental, value1);
} else {
mlir::Value res = genScalarCombiner(builder, loc, op, ty, value1, value2);
builder.create<fir::StoreOp>(loc, res, value1);
Expand Down Expand Up @@ -932,9 +967,6 @@ genReductions(const Fortran::parser::AccObjectListWithReduction &objectList,
mlir::acc::DataBoundsOp>(converter, builder, semanticsContext, stmtCtx,
accObject, operandLocation, asFortran, bounds);

if (hasDynamicShape(bounds))
TODO(operandLocation, "OpenACC reductions with dynamic shaped array");

mlir::Type reductionTy = fir::unwrapRefType(baseAddr.getType());
if (auto seqTy = mlir::dyn_cast<fir::SequenceType>(reductionTy))
reductionTy = seqTy.getEleTy();
Expand All @@ -953,6 +985,8 @@ genReductions(const Fortran::parser::AccObjectListWithReduction &objectList,
std::string recipeName = fir::getTypeAsString(
ty, converter.getKindMap(),
("reduction_" + stringifyReductionOperator(mlirOp)).str());
if (hasDynamicShape(bounds))
ty = baseAddr.getType();
mlir::acc::ReductionRecipeOp recipe =
Fortran::lower::createOrGetReductionRecipe(
builder, recipeName, operandLocation, ty, mlirOp, bounds);
Expand Down
62 changes: 62 additions & 0 deletions flang/lib/Optimizer/Builder/HLFIRTools.cpp
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Expand Up @@ -14,6 +14,7 @@
#include "flang/Optimizer/Builder/Character.h"
#include "flang/Optimizer/Builder/FIRBuilder.h"
#include "flang/Optimizer/Builder/MutableBox.h"
#include "flang/Optimizer/Builder/Runtime/Allocatable.h"
#include "flang/Optimizer/Builder/Todo.h"
#include "flang/Optimizer/HLFIR/HLFIROps.h"
#include "mlir/IR/IRMapping.h"
Expand Down Expand Up @@ -1030,3 +1031,64 @@ bool hlfir::elementalOpMustProduceTemp(hlfir::ElementalOp elemental) {

return false;
}

std::pair<hlfir::Entity, mlir::Value>
hlfir::createTempFromMold(mlir::Location loc, fir::FirOpBuilder &builder,
hlfir::Entity mold) {
llvm::SmallVector<mlir::Value> lenParams;
hlfir::genLengthParameters(loc, builder, mold, lenParams);
llvm::StringRef tmpName{".tmp"};
mlir::Value alloc;
mlir::Value isHeapAlloc;
mlir::Value shape{};
fir::FortranVariableFlagsAttr declAttrs;

if (mold.isPolymorphic()) {
// Create unallocated polymorphic temporary using the dynamic type
// of the mold. The static type of the temporary matches
// the static type of the mold, but then the dynamic type
// of the mold is applied to the temporary's descriptor.

if (mold.isArray())
hlfir::genShape(loc, builder, mold);

// Create polymorphic allocatable box on the stack.
mlir::Type boxHeapType = fir::HeapType::get(fir::unwrapRefType(
mlir::cast<fir::BaseBoxType>(mold.getType()).getEleTy()));
// The box must be initialized, because AllocatableApplyMold
// may read its contents (e.g. for checking whether it is allocated).
alloc = fir::factory::genNullBoxStorage(builder, loc,
fir::ClassType::get(boxHeapType));
// The temporary is unallocated even after AllocatableApplyMold below.
// If the temporary is used as assignment LHS it will be automatically
// allocated on the heap, as long as we use Assign family
// runtime functions. So set MustFree to true.
isHeapAlloc = builder.createBool(loc, true);
declAttrs = fir::FortranVariableFlagsAttr::get(
builder.getContext(), fir::FortranVariableFlagsEnum::allocatable);
} else if (mold.isArray()) {
mlir::Type sequenceType =
hlfir::getFortranElementOrSequenceType(mold.getType());
shape = hlfir::genShape(loc, builder, mold);
auto extents = hlfir::getIndexExtents(loc, builder, shape);
alloc = builder.createHeapTemporary(loc, sequenceType, tmpName, extents,
lenParams);
isHeapAlloc = builder.createBool(loc, true);
} else {
alloc = builder.createTemporary(loc, mold.getFortranElementType(), tmpName,
/*shape=*/std::nullopt, lenParams);
isHeapAlloc = builder.createBool(loc, false);
}
auto declareOp = builder.create<hlfir::DeclareOp>(loc, alloc, tmpName, shape,
lenParams, declAttrs);
if (mold.isPolymorphic()) {
int rank = mold.getRank();
// TODO: should probably read rank from the mold.
if (rank < 0)
TODO(loc, "create temporary for assumed rank polymorphic");
fir::runtime::genAllocatableApplyMold(builder, loc, alloc,
mold.getFirBase(), rank);
}

return {hlfir::Entity{declareOp.getBase()}, isHeapAlloc};
}
65 changes: 2 additions & 63 deletions flang/lib/Optimizer/HLFIR/Transforms/BufferizeHLFIR.cpp
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Expand Up @@ -101,67 +101,6 @@ static mlir::Value getBufferizedExprMustFreeFlag(mlir::Value bufferizedExpr) {
TODO(bufferizedExpr.getLoc(), "general extract storage case");
}

static std::pair<hlfir::Entity, mlir::Value>
createTempFromMold(mlir::Location loc, fir::FirOpBuilder &builder,
hlfir::Entity mold) {
llvm::SmallVector<mlir::Value> lenParams;
hlfir::genLengthParameters(loc, builder, mold, lenParams);
llvm::StringRef tmpName{".tmp"};
mlir::Value alloc;
mlir::Value isHeapAlloc;
mlir::Value shape{};
fir::FortranVariableFlagsAttr declAttrs;

if (mold.isPolymorphic()) {
// Create unallocated polymorphic temporary using the dynamic type
// of the mold. The static type of the temporary matches
// the static type of the mold, but then the dynamic type
// of the mold is applied to the temporary's descriptor.

if (mold.isArray())
hlfir::genShape(loc, builder, mold);

// Create polymorphic allocatable box on the stack.
mlir::Type boxHeapType = fir::HeapType::get(fir::unwrapRefType(
mlir::cast<fir::BaseBoxType>(mold.getType()).getEleTy()));
// The box must be initialized, because AllocatableApplyMold
// may read its contents (e.g. for checking whether it is allocated).
alloc = fir::factory::genNullBoxStorage(builder, loc,
fir::ClassType::get(boxHeapType));
// The temporary is unallocated even after AllocatableApplyMold below.
// If the temporary is used as assignment LHS it will be automatically
// allocated on the heap, as long as we use Assign family
// runtime functions. So set MustFree to true.
isHeapAlloc = builder.createBool(loc, true);
declAttrs = fir::FortranVariableFlagsAttr::get(
builder.getContext(), fir::FortranVariableFlagsEnum::allocatable);
} else if (mold.isArray()) {
mlir::Type sequenceType =
hlfir::getFortranElementOrSequenceType(mold.getType());
shape = hlfir::genShape(loc, builder, mold);
auto extents = hlfir::getIndexExtents(loc, builder, shape);
alloc = builder.createHeapTemporary(loc, sequenceType, tmpName, extents,
lenParams);
isHeapAlloc = builder.createBool(loc, true);
} else {
alloc = builder.createTemporary(loc, mold.getFortranElementType(), tmpName,
/*shape=*/std::nullopt, lenParams);
isHeapAlloc = builder.createBool(loc, false);
}
auto declareOp = builder.create<hlfir::DeclareOp>(loc, alloc, tmpName, shape,
lenParams, declAttrs);
if (mold.isPolymorphic()) {
int rank = mold.getRank();
// TODO: should probably read rank from the mold.
if (rank < 0)
TODO(loc, "create temporary for assumed rank polymorphic");
fir::runtime::genAllocatableApplyMold(builder, loc, alloc,
mold.getFirBase(), rank);
}

return {hlfir::Entity{declareOp.getBase()}, isHeapAlloc};
}

static std::pair<hlfir::Entity, mlir::Value>
createArrayTemp(mlir::Location loc, fir::FirOpBuilder &builder,
mlir::Type exprType, mlir::Value shape,
Expand Down Expand Up @@ -239,7 +178,7 @@ struct AsExprOpConversion : public mlir::OpConversionPattern<hlfir::AsExprOp> {
}
// Otherwise, create a copy in a new buffer.
hlfir::Entity source = hlfir::Entity{adaptor.getVar()};
auto [temp, cleanup] = createTempFromMold(loc, builder, source);
auto [temp, cleanup] = hlfir::createTempFromMold(loc, builder, source);
builder.create<hlfir::AssignOp>(loc, source, temp, temp.isAllocatable(),
/*keep_lhs_length_if_realloc=*/false,
/*temporary_lhs=*/true);
Expand Down Expand Up @@ -596,7 +535,7 @@ struct AssociateOpConversion
// non-trivial value with more than one use. We will have to make a copy and
// use that
hlfir::Entity source = hlfir::Entity{bufferizedExpr};
auto [temp, cleanup] = createTempFromMold(loc, builder, source);
auto [temp, cleanup] = hlfir::createTempFromMold(loc, builder, source);
builder.create<hlfir::AssignOp>(loc, source, temp, temp.isAllocatable(),
/*keep_lhs_length_if_realloc=*/false,
/*temporary_lhs=*/true);
Expand Down
79 changes: 79 additions & 0 deletions flang/test/Lower/OpenACC/acc-reduction.f90
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Expand Up @@ -3,6 +3,61 @@
! RUN: bbc -fopenacc -emit-fir %s -o - | FileCheck %s --check-prefixes=CHECK,FIR
! RUN: bbc -fopenacc -emit-hlfir %s -o - | FileCheck %s --check-prefixes=CHECK,HLFIR

! CHECK-LABEL: acc.reduction.recipe @"reduction_max_ref_?xf32" : !fir.box<!fir.array<?xf32>> reduction_operator <max> init {
! CHECK: ^bb0(%[[ARG0:.*]]: !fir.box<!fir.array<?xf32>>):
! CHECK: %[[INIT_VALUE:.*]] = arith.constant -1.401300e-45 : f32
! HLFIR: %[[C0:.*]] = arith.constant 0 : index
! HLFIR: %[[BOX_DIMS:.*]]:3 = fir.box_dims %[[ARG0]], %[[C0]] : (!fir.box<!fir.array<?xf32>>, index) -> (index, index, index)
! HLFIR: %[[SHAPE:.*]] = fir.shape %[[BOX_DIMS]]#1 : (index) -> !fir.shape<1>
! HLFIR: %[[TEMP:.*]] = fir.allocmem !fir.array<?xf32>, %0#1 {bindc_name = ".tmp", uniq_name = ""}
! HLFIR: %[[DECLARE:.*]]:2 = hlfir.declare %[[TEMP]](%[[SHAPE]]) {uniq_name = ".tmp"} : (!fir.heap<!fir.array<?xf32>>, !fir.shape<1>) -> (!fir.box<!fir.array<?xf32>>, !fir.heap<!fir.array<?xf32>>)
! HLFIR: hlfir.assign %[[INIT_VALUE]] to %[[DECLARE]]#0 : f32, !fir.box<!fir.array<?xf32>>
! HLFIR: acc.yield %[[DECLARE]]#0 : !fir.box<!fir.array<?xf32>>
! CHECK: } combiner {
! CHECK: ^bb0(%[[ARG0:.*]]: !fir.box<!fir.array<?xf32>>, %[[ARG1:.*]]: !fir.box<!fir.array<?xf32>>):
! HLFIR: %[[BOX_DIMS:.*]]:3 = fir.box_dims %[[ARG0]], %{{.*}} : (!fir.box<!fir.array<?xf32>>, index) -> (index, index, index)
! HLFIR: %[[SHAPE:.*]] = fir.shape %[[BOX_DIMS]]#1 : (index) -> !fir.shape<1>
! HLFIR: %[[ELEMENTAL:.*]] = hlfir.elemental %[[SHAPE]] unordered : (!fir.shape<1>) -> !hlfir.expr<?xf32> {
! HLFIR: ^bb0(%arg2: index):
! HLFIR: %[[DES_V1:.*]] = hlfir.designate %[[ARG0]] (%{{.*}}) : (!fir.box<!fir.array<?xf32>>, index) -> !fir.ref<f32>
! HLFIR: %[[DES_V2:.*]] = hlfir.designate %[[ARG1]] (%{{.*}}) : (!fir.box<!fir.array<?xf32>>, index) -> !fir.ref<f32>
! HLFIR: %[[LOAD_V1:.*]] = fir.load %[[DES_V1]] : !fir.ref<f32>
! HLFIR: %[[LOAD_V2:.*]] = fir.load %[[DES_V2]] : !fir.ref<f32>
! HLFIR: %[[CMPF:.*]] = arith.cmpf ogt, %[[LOAD_V1]], %[[LOAD_V2]] : f32
! HLFIR: %[[SELECT:.*]] = arith.select %[[CMPF]], %[[LOAD_V1]], %[[LOAD_V2]] : f32
! HLFIR: hlfir.yield_element %[[SELECT]] : f32
! HLFIR: }
! HLFIR: hlfir.assign %[[ELEMENTAL]] to %[[ARG0]] : !hlfir.expr<?xf32>, !fir.box<!fir.array<?xf32>>
! CHECK: acc.yield %[[ARG0]] : !fir.box<!fir.array<?xf32>>
! CHECK: }

! CHECK-LABEL: acc.reduction.recipe @"reduction_add_ref_?xi32" : !fir.box<!fir.array<?xi32>> reduction_operator <add> init {
! CHECK: ^bb0(%[[ARG0:.*]]: !fir.box<!fir.array<?xi32>>):
! HLFIR: %[[INIT_VALUE:.*]] = arith.constant 0 : i32
! HLFIR: %[[C0:.*]] = arith.constant 0 : index
! HLFIR: %[[BOX_DIMS:.*]]:3 = fir.box_dims %[[ARG0]], %[[C0]] : (!fir.box<!fir.array<?xi32>>, index) -> (index, index, index)
! HLFIR: %[[SHAPE:.*]] = fir.shape %[[BOX_DIMS]]#1 : (index) -> !fir.shape<1>
! HLFIR: %[[TEMP:.*]] = fir.allocmem !fir.array<?xi32>, %[[BOX_DIMS]]#1 {bindc_name = ".tmp", uniq_name = ""}
! HLFIR: %[[DECLARE:.*]]:2 = hlfir.declare %[[TEMP]](%[[SHAPE]]) {uniq_name = ".tmp"} : (!fir.heap<!fir.array<?xi32>>, !fir.shape<1>) -> (!fir.box<!fir.array<?xi32>>, !fir.heap<!fir.array<?xi32>>)
! HLFIR: hlfir.assign %[[INIT_VALUE]] to %[[DECLARE]]#0 : i32, !fir.box<!fir.array<?xi32>>
! HLFIR: acc.yield %[[DECLARE]]#0 : !fir.box<!fir.array<?xi32>>
! CHECK: } combiner {
! CHECK: ^bb0(%[[V1:.*]]: !fir.box<!fir.array<?xi32>>, %[[V2:.*]]: !fir.box<!fir.array<?xi32>>):
! HLFIR: %[[BOX_DIMS]]:3 = fir.box_dims %[[V1]], %{{.*}} : (!fir.box<!fir.array<?xi32>>, index) -> (index, index, index)
! HLFIR: %[[SHAPE:.*]] = fir.shape %[[BOX_DIMS]]#1 : (index) -> !fir.shape<1>
! HLFIR: %[[ELEMENTAL:.*]] = hlfir.elemental %[[SHAPE]] unordered : (!fir.shape<1>) -> !hlfir.expr<?xi32> {
! HLFIR: ^bb0(%{{.*}}: index):
! HLFIR: %[[DES_V1:.*]] = hlfir.designate %[[V1]] (%{{.*}}) : (!fir.box<!fir.array<?xi32>>, index) -> !fir.ref<i32>
! HLFIR: %[[DES_V2:.*]] = hlfir.designate %[[V2]] (%{{.*}}) : (!fir.box<!fir.array<?xi32>>, index) -> !fir.ref<i32>
! HLFIR: %[[LOAD_V1:.*]] = fir.load %[[DES_V1]] : !fir.ref<i32>
! HLFIR: %[[LOAD_V2:.*]] = fir.load %[[DES_V2]] : !fir.ref<i32>
! HLFIR: %[[COMBINED:.*]] = arith.addi %[[LOAD_V1]], %[[LOAD_V2]] : i32
! HLFIR: hlfir.yield_element %[[COMBINED]] : i32
! HLFIR: }
! HLFIR: hlfir.assign %[[ELEMENTAL]] to %[[V1]] : !hlfir.expr<?xi32>, !fir.box<!fir.array<?xi32>>
! CHECK: acc.yield %arg0 : !fir.box<!fir.array<?xi32>>
! CHECK: }

! CHECK-LABEL: acc.reduction.recipe @reduction_mul_ref_z32 : !fir.ref<!fir.complex<4>> reduction_operator <mul> init {
! CHECK: ^bb0(%{{.*}}: !fir.ref<!fir.complex<4>>):
! CHECK: %[[REAL:.*]] = arith.constant 1.000000e+00 : f32
Expand Down Expand Up @@ -1005,3 +1060,27 @@ subroutine acc_reduction_add_static_slice(a)
! FIR: %[[RED:.*]] = acc.reduction varPtr(%[[ARG0]] : !fir.ref<!fir.array<100xi32>>) bounds(%[[BOUND]]) -> !fir.ref<!fir.array<100xi32>> {name = "a(11:20)"}
! HLFIR: %[[RED:.*]] = acc.reduction varPtr(%[[DECLARG0]]#1 : !fir.ref<!fir.array<100xi32>>) bounds(%[[BOUND]]) -> !fir.ref<!fir.array<100xi32>> {name = "a(11:20)"}
! CHECK: acc.parallel reduction(@reduction_add_ref_100xi32 -> %[[RED]] : !fir.ref<!fir.array<100xi32>>)

subroutine acc_reduction_add_dynamic_extent_add(a)
integer :: a(:)
!$acc parallel reduction(+:a)
!$acc end parallel
end subroutine

! CHECK-LABEL: func.func @_QPacc_reduction_add_dynamic_extent_add(
! CHECK-SAME: %[[ARG0:.*]]: !fir.box<!fir.array<?xi32>> {fir.bindc_name = "a"})
! HLFIR: %[[DECLARG0:.*]]:2 = hlfir.declare %[[ARG0]]
! HLFIR: %[[RED:.*]] = acc.reduction varPtr(%{{.*}} : !fir.ref<!fir.array<?xi32>>) bounds(%{{.*}}) -> !fir.ref<!fir.array<?xi32>> {name = "a"}
! HLFIR: acc.parallel reduction(@"reduction_add_ref_?xi32" -> %[[RED:.*]] : !fir.ref<!fir.array<?xi32>>)

subroutine acc_reduction_add_dynamic_extent_max(a)
real :: a(:)
!$acc parallel reduction(max:a)
!$acc end parallel
end subroutine

! CHECK-LABEL: func.func @_QPacc_reduction_add_dynamic_extent_max(
! CHECK-SAME: %[[ARG0:.*]]: !fir.box<!fir.array<?xf32>> {fir.bindc_name = "a"})
! HLFIR: %[[DECLARG0:.*]]:2 = hlfir.declare %[[ARG0]]
! HLFIR: %[[RED:.*]] = acc.reduction varPtr(%{{.*}} : !fir.ref<!fir.array<?xf32>>) bounds(%{{.*}}) -> !fir.ref<!fir.array<?xf32>> {name = "a"}
! HLFIR: acc.parallel reduction(@"reduction_max_ref_?xf32" -> %[[RED]] : !fir.ref<!fir.array<?xf32>>) {