[mlir][OpenMP] set correct insert point after creating a barrier #142997
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| @llvm/pr-subscribers-mlir-llvm @llvm/pr-subscribers-flang-openmp Author: Tom Eccles (tblah) ChangesFixes #138436 Full diff: https://github.com/llvm/llvm-project/pull/142997.diff 2 Files Affected:
diff --git a/mlir/lib/Target/LLVMIR/Dialect/OpenMP/OpenMPToLLVMIRTranslation.cpp b/mlir/lib/Target/LLVMIR/Dialect/OpenMP/OpenMPToLLVMIRTranslation.cpp index 4a6605e9c74cb..ec1a9c909c94a 100644 --- a/mlir/lib/Target/LLVMIR/Dialect/OpenMP/OpenMPToLLVMIRTranslation.cpp +++ b/mlir/lib/Target/LLVMIR/Dialect/OpenMP/OpenMPToLLVMIRTranslation.cpp @@ -5737,7 +5737,13 @@ convertHostOrTargetOperation(Operation *op, llvm::IRBuilderBase &builder, llvm::OpenMPIRBuilder::InsertPointOrErrorTy afterIP = ompBuilder->createBarrier(builder.saveIP(), llvm::omp::OMPD_barrier); - return handleError(afterIP, *op); + LogicalResult res = handleError(afterIP, *op); + if (res.succeeded()) { + // If the barrier generated a cancellation check, the insertion + // point might now need to be changed to a new continuation block + builder.restoreIP(*afterIP); + } + return res; }) .Case([&](omp::TaskyieldOp op) { if (failed(checkImplementationStatus(*op))) diff --git a/mlir/test/Target/LLVMIR/openmp-barrier-cancel.mlir b/mlir/test/Target/LLVMIR/openmp-barrier-cancel.mlir new file mode 100644 index 0000000000000..c4b245667a1f3 --- /dev/null +++ b/mlir/test/Target/LLVMIR/openmp-barrier-cancel.mlir @@ -0,0 +1,50 @@ +// RUN: mlir-translate --mlir-to-llvmir %s | FileCheck %s + +// Regression test for a compiler crash. Ensure that the insertion point is set +// correctly after the barrier's cancel check + +llvm.func @test() { + omp.parallel { + omp.cancel cancellation_construct_type(parallel) + omp.barrier + omp.terminator + } + llvm.return +} + +// CHECK-LABEL: define internal void @test..omp_par +// CHECK: omp.par.entry: +// CHECK: %[[VAL_4:.*]] = alloca i32, align 4 +// CHECK: %[[VAL_5:.*]] = load i32, ptr %[[VAL_6:.*]], align 4 +// CHECK: store i32 %[[VAL_5]], ptr %[[VAL_4]], align 4 +// CHECK: %[[VAL_7:.*]] = load i32, ptr %[[VAL_4]], align 4 +// CHECK: br label %[[VAL_8:.*]] +// CHECK: omp.region.after_alloca: ; preds = %[[VAL_9:.*]] +// CHECK: br label %[[VAL_10:.*]] +// CHECK: omp.par.region: ; preds = %[[VAL_8]] +// CHECK: br label %[[VAL_11:.*]] +// CHECK: omp.par.region1: ; preds = %[[VAL_10]] +// CHECK: %[[VAL_12:.*]] = call i32 @__kmpc_global_thread_num(ptr @1) +// CHECK: %[[VAL_13:.*]] = call i32 @__kmpc_cancel(ptr @1, i32 %[[VAL_12]], i32 1) +// CHECK: %[[VAL_14:.*]] = icmp eq i32 %[[VAL_13]], 0 +// CHECK: br i1 %[[VAL_14]], label %[[VAL_15:.*]], label %[[VAL_16:.*]] +// CHECK: omp.par.region1.cncl: ; preds = %[[VAL_11]] +// CHECK: %[[VAL_17:.*]] = call i32 @__kmpc_global_thread_num(ptr @1) +// CHECK: %[[VAL_18:.*]] = call i32 @__kmpc_cancel_barrier(ptr @2, i32 %[[VAL_17]]) +// CHECK: br label %[[VAL_19:.*]] +// CHECK: omp.par.region1.split: ; preds = %[[VAL_11]] +// CHECK: %[[VAL_20:.*]] = call i32 @__kmpc_global_thread_num(ptr @1) +// CHECK: %[[VAL_21:.*]] = call i32 @__kmpc_cancel_barrier(ptr @3, i32 %[[VAL_20]]) +// CHECK: %[[VAL_22:.*]] = icmp eq i32 %[[VAL_21]], 0 +// CHECK: br i1 %[[VAL_22]], label %[[VAL_23:.*]], label %[[VAL_24:.*]] +// CHECK: omp.par.region1.split.cncl: ; preds = %[[VAL_15]] +// CHECK: br label %[[VAL_19]] +// CHECK: omp.par.region1.split.cont: ; preds = %[[VAL_15]] +// CHECK: br label %[[VAL_25:.*]] +// CHECK: omp.region.cont: ; preds = %[[VAL_23]] +// CHECK: br label %[[VAL_26:.*]] +// CHECK: omp.par.pre_finalize: ; preds = %[[VAL_25]] +// CHECK: br label %[[VAL_19]] +// CHECK: omp.par.exit.exitStub: ; preds = %[[VAL_26]], %[[VAL_24]], %[[VAL_16]] +// CHECK: ret void + |
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| @llvm/pr-subscribers-mlir-openmp Author: Tom Eccles (tblah) ChangesFixes #138436 Full diff: https://github.com/llvm/llvm-project/pull/142997.diff 2 Files Affected:
diff --git a/mlir/lib/Target/LLVMIR/Dialect/OpenMP/OpenMPToLLVMIRTranslation.cpp b/mlir/lib/Target/LLVMIR/Dialect/OpenMP/OpenMPToLLVMIRTranslation.cpp index 4a6605e9c74cb..ec1a9c909c94a 100644 --- a/mlir/lib/Target/LLVMIR/Dialect/OpenMP/OpenMPToLLVMIRTranslation.cpp +++ b/mlir/lib/Target/LLVMIR/Dialect/OpenMP/OpenMPToLLVMIRTranslation.cpp @@ -5737,7 +5737,13 @@ convertHostOrTargetOperation(Operation *op, llvm::IRBuilderBase &builder, llvm::OpenMPIRBuilder::InsertPointOrErrorTy afterIP = ompBuilder->createBarrier(builder.saveIP(), llvm::omp::OMPD_barrier); - return handleError(afterIP, *op); + LogicalResult res = handleError(afterIP, *op); + if (res.succeeded()) { + // If the barrier generated a cancellation check, the insertion + // point might now need to be changed to a new continuation block + builder.restoreIP(*afterIP); + } + return res; }) .Case([&](omp::TaskyieldOp op) { if (failed(checkImplementationStatus(*op))) diff --git a/mlir/test/Target/LLVMIR/openmp-barrier-cancel.mlir b/mlir/test/Target/LLVMIR/openmp-barrier-cancel.mlir new file mode 100644 index 0000000000000..c4b245667a1f3 --- /dev/null +++ b/mlir/test/Target/LLVMIR/openmp-barrier-cancel.mlir @@ -0,0 +1,50 @@ +// RUN: mlir-translate --mlir-to-llvmir %s | FileCheck %s + +// Regression test for a compiler crash. Ensure that the insertion point is set +// correctly after the barrier's cancel check + +llvm.func @test() { + omp.parallel { + omp.cancel cancellation_construct_type(parallel) + omp.barrier + omp.terminator + } + llvm.return +} + +// CHECK-LABEL: define internal void @test..omp_par +// CHECK: omp.par.entry: +// CHECK: %[[VAL_4:.*]] = alloca i32, align 4 +// CHECK: %[[VAL_5:.*]] = load i32, ptr %[[VAL_6:.*]], align 4 +// CHECK: store i32 %[[VAL_5]], ptr %[[VAL_4]], align 4 +// CHECK: %[[VAL_7:.*]] = load i32, ptr %[[VAL_4]], align 4 +// CHECK: br label %[[VAL_8:.*]] +// CHECK: omp.region.after_alloca: ; preds = %[[VAL_9:.*]] +// CHECK: br label %[[VAL_10:.*]] +// CHECK: omp.par.region: ; preds = %[[VAL_8]] +// CHECK: br label %[[VAL_11:.*]] +// CHECK: omp.par.region1: ; preds = %[[VAL_10]] +// CHECK: %[[VAL_12:.*]] = call i32 @__kmpc_global_thread_num(ptr @1) +// CHECK: %[[VAL_13:.*]] = call i32 @__kmpc_cancel(ptr @1, i32 %[[VAL_12]], i32 1) +// CHECK: %[[VAL_14:.*]] = icmp eq i32 %[[VAL_13]], 0 +// CHECK: br i1 %[[VAL_14]], label %[[VAL_15:.*]], label %[[VAL_16:.*]] +// CHECK: omp.par.region1.cncl: ; preds = %[[VAL_11]] +// CHECK: %[[VAL_17:.*]] = call i32 @__kmpc_global_thread_num(ptr @1) +// CHECK: %[[VAL_18:.*]] = call i32 @__kmpc_cancel_barrier(ptr @2, i32 %[[VAL_17]]) +// CHECK: br label %[[VAL_19:.*]] +// CHECK: omp.par.region1.split: ; preds = %[[VAL_11]] +// CHECK: %[[VAL_20:.*]] = call i32 @__kmpc_global_thread_num(ptr @1) +// CHECK: %[[VAL_21:.*]] = call i32 @__kmpc_cancel_barrier(ptr @3, i32 %[[VAL_20]]) +// CHECK: %[[VAL_22:.*]] = icmp eq i32 %[[VAL_21]], 0 +// CHECK: br i1 %[[VAL_22]], label %[[VAL_23:.*]], label %[[VAL_24:.*]] +// CHECK: omp.par.region1.split.cncl: ; preds = %[[VAL_15]] +// CHECK: br label %[[VAL_19]] +// CHECK: omp.par.region1.split.cont: ; preds = %[[VAL_15]] +// CHECK: br label %[[VAL_25:.*]] +// CHECK: omp.region.cont: ; preds = %[[VAL_23]] +// CHECK: br label %[[VAL_26:.*]] +// CHECK: omp.par.pre_finalize: ; preds = %[[VAL_25]] +// CHECK: br label %[[VAL_19]] +// CHECK: omp.par.exit.exitStub: ; preds = %[[VAL_26]], %[[VAL_24]], %[[VAL_16]] +// CHECK: ret void + |
bhandarkar-pranav approved these changes Jun 5, 2025
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| The CI failure is the buildkite bug with precompiled headers discussed in #141927 and so is not related to this PR. |
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Fixes #138436