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Differential D158752

[mlir][Conversion] Allow lowering to fixed arrays of scalable vectors
ClosedPublic

Authored by benmxwl-arm on Aug 24 2023, 9:41 AM.

Details

Reviewers
c-rhodes
awarzynski
aartbik
ftynse
dcaballe
Commits
rG665995b9182b: [mlir][Conversion] Allow lowering to fixed arrays of scalable vectors
Summary

This allows lowering vector types like: vector<3x[4]> or vector<3x2x[4]>
to LLVM IR, i.e. vectors where the trailing dim is scalable.

This is contingent on:
https://discourse.llvm.org/t/rfc-enable-arrays-of-scalable-vector-types/72935

More tests will be added in later patches, however, some MLIR fixes are
needed first.

Depends on: D158517

Diff Detail

Event Timeline

benmxwl-arm created this revision.Aug 24 2023, 9:41 AM
Herald added a reviewer: aartbik. · View Herald TranscriptAug 24 2023, 9:41 AM
Herald added a reviewer: ftynse. · View Herald Transcript
Herald added a reviewer: dcaballe. · View Herald Transcript
Herald added a project: Restricted Project. · View Herald Transcript
Herald added subscribers: gysit, Dinistro, bviyer and 24 others. · View Herald Transcript
benmxwl-arm requested review of this revision.Aug 24 2023, 9:41 AM
Herald added a project: Restricted Project. · View Herald TranscriptAug 24 2023, 9:41 AM
Herald added subscribers: alextsao1999, stephenneuendorffer, nicolasvasilache. · View Herald Transcript
benmxwl-arm added parent revisions: D158751: [mlir][BuiltinTypes] Add VectorType::sliceDims() and drop[Front/Back]Dims(), D158517: [IR] Enable load/store/alloca for arrays of scalable vectors..Aug 24 2023, 9:44 AM
Harbormaster completed remote builds in B254656: Diff 553172.Aug 24 2023, 10:39 AM
benmxwl-arm updated this revision to Diff 554432.Aug 29 2023, 11:04 AM
  • Remove dependency on (abandoned) VectorType helper methods
benmxwl-arm removed a parent revision: D158751: [mlir][BuiltinTypes] Add VectorType::sliceDims() and drop[Front/Back]Dims().Aug 29 2023, 11:05 AM
benmxwl-arm edited the summary of this revision. (Show Details)Aug 29 2023, 11:13 AM
Harbormaster completed remote builds in B255588: Diff 554432.Aug 29 2023, 3:26 PM
benmxwl-arm mentioned this in D159482: [mlir][VectorOps] Don't drop scalable dims when lowering transfer_reads/writes (in VectorToLLVM).Sep 7 2023, 8:27 AM
benmxwl-arm added a child revision: D159482: [mlir][VectorOps] Don't drop scalable dims when lowering transfer_reads/writes (in VectorToLLVM).Sep 7 2023, 8:28 AM
awarzynski accepted this revision.Sep 14 2023, 7:32 AM

D158517 has just landed, so LGTM, thank you! 🙏🏻

This revision is now accepted and ready to land.Sep 14 2023, 7:32 AM
benmxwl-arm updated this revision to Diff 556790.Sep 14 2023, 8:52 AM
  • Return failure rather than assert.
Harbormaster completed remote builds in B257232: Diff 556790.Sep 14 2023, 9:37 AM
Closed by commit rG665995b9182b: [mlir][Conversion] Allow lowering to fixed arrays of scalable vectors (authored by benmxwl-arm). · Explain WhySep 15 2023, 2:34 AM
This revision was automatically updated to reflect the committed changes.
benmxwl-arm added a commit: rG665995b9182b: [mlir][Conversion] Allow lowering to fixed arrays of scalable vectors.

Revision Contents

PathSize
mlir/
lib/
Conversion/
LLVMCommon/
3 lines
test/
Conversion/
VectorToLLVM/
10 lines

Diff 556837

mlir/lib/Conversion/LLVMCommon/TypeConverter.cpp

Show First 20 Lines • Show All 501 Lines • ▼ Show 20 LinesFailureOr<Type> LLVMTypeConverter::convertVectorType(VectorType type) const {
if (!elementType) if (!elementType)
return {}; return {};
if (type.getShape().empty()) if (type.getShape().empty())
return VectorType::get({1}, elementType); return VectorType::get({1}, elementType);
Type vectorType = VectorType::get(type.getShape().back(), elementType, Type vectorType = VectorType::get(type.getShape().back(), elementType,
type.getScalableDims().back()); type.getScalableDims().back());
assert(LLVM::isCompatibleVectorType(vectorType) && assert(LLVM::isCompatibleVectorType(vectorType) &&
"expected vector type compatible with the LLVM dialect"); "expected vector type compatible with the LLVM dialect");
if (type.isScalable() && (type.getRank() > 1)) // Only the trailing dimension can be scalable.
if (llvm::is_contained(type.getScalableDims().drop_back(), true))
return failure(); return failure();
auto shape = type.getShape(); auto shape = type.getShape();
for (int i = shape.size() - 2; i >= 0; --i) for (int i = shape.size() - 2; i >= 0; --i)
vectorType = LLVM::LLVMArrayType::get(vectorType, shape[i]); vectorType = LLVM::LLVMArrayType::get(vectorType, shape[i]);
return vectorType; return vectorType;
} }
/// Convert a type in the context of the default or bare pointer calling /// Convert a type in the context of the default or bare pointer calling
▲ Show 20 Lines • Show All 168 Lines • Show Last 20 Lines

mlir/test/Conversion/VectorToLLVM/vector-to-llvm.mlir

Show First 20 Lines • Show All 2,254 Lines • ▼ Show 20 Lines
// CHECK-LABEL: @vector_scalable_extract // CHECK-LABEL: @vector_scalable_extract
// CHECK-SAME: %[[VEC:.*]]: vector<[4]xf32> // CHECK-SAME: %[[VEC:.*]]: vector<[4]xf32>
func.func @vector_scalable_extract(%vec: vector<[4]xf32>) -> vector<8xf32> { func.func @vector_scalable_extract(%vec: vector<[4]xf32>) -> vector<8xf32> {
// CHECK-NEXT: %{{.*}} = llvm.intr.vector.extract %[[VEC]][0] : vector<8xf32> from vector<[4]xf32> // CHECK-NEXT: %{{.*}} = llvm.intr.vector.extract %[[VEC]][0] : vector<8xf32> from vector<[4]xf32>
%0 = vector.scalable.extract %vec[0] : vector<8xf32> from vector<[4]xf32> %0 = vector.scalable.extract %vec[0] : vector<8xf32> from vector<[4]xf32>
return %0 : vector<8xf32> return %0 : vector<8xf32>
} }
// -----
// CHECK-LABEL: @make_fixed_vector_of_scalable_vector
func.func @make_fixed_vector_of_scalable_vector(%f : f64) -> vector<3x[2]xf64>
{
// CHECK: %{{.*}} = llvm.mlir.undef : !llvm.array<3 x vector<[2]xf64>>
%res = vector.broadcast %f : f64 to vector<3x[2]xf64>
return %res : vector<3x[2]xf64>
}