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[flang][OpenMP] Parallel region codegen support #424

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Merged
merged 1 commit into from
Sep 22, 2020
Merged

[flang][OpenMP] Parallel region codegen support #424

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4 changes: 4 additions & 0 deletions flang/lib/Lower/Bridge.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -1072,7 +1072,11 @@ class FirConverter : public Fortran::lower::AbstractConverter {
}

void genFIR(const Fortran::parser::OpenMPConstruct &omp) {
auto insertPt = builder->saveInsertionPoint();
genOpenMPConstruct(*this, getEval(), omp);
for (auto &e : getEval().getNestedEvaluations())
genFIR(e);
builder->restoreInsertionPoint(insertPt);
}

void genFIR(const Fortran::parser::OmpEndLoopDirective &omp) {
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5 changes: 3 additions & 2 deletions flang/lib/Lower/OpenMP.cpp
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Expand Up @@ -87,7 +87,6 @@ genOMP(Fortran::lower::AbstractConverter &absConv,
if (parallelDirective.v == llvm::omp::OMPD_parallel) {
auto &firOpBuilder = absConv.getFirOpBuilder();
auto currentLocation = absConv.getCurrentLocation();
auto insertPt = firOpBuilder.saveInsertionPoint();

// Clauses.
// FIXME: Add support for other clauses.
Expand Down Expand Up @@ -117,7 +116,9 @@ genOMP(Fortran::lower::AbstractConverter &absConv,
firOpBuilder.setInsertionPointToStart(&block);
// Ensure the block is well-formed.
firOpBuilder.create<mlir::omp::TerminatorOp>(currentLocation);
firOpBuilder.restoreInsertionPoint(insertPt);

// Place the insertion point to the start of the first block.
firOpBuilder.setInsertionPointToStart(&block);
}
}

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118 changes: 118 additions & 0 deletions flang/test/Lower/OpenMP/omp-parallel-region.f90
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@@ -0,0 +1,118 @@
! This test checks lowering of OpenMP parallel Directive with arbitrary code
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Can you add more tests?

  1. With a fir loop inside.
  2. With an if statement.
  3. with a goto statement (branching to inside the region).

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Sure will take care of this in next revision.

! inside it.

! RUN: bbc -fopenmp -emit-fir %s -o - | \
! RUN: FileCheck %s --check-prefix=FIRDialect
! RUN: bbc -fopenmp -emit-llvm %s -o - | \
! RUN: FileCheck %s --check-prefix=LLVMIRDialect
! RUN: bbc -fopenmp -emit-fir %s -o - | \
! RUN: tco | FileCheck %s --check-prefix=LLVMIR

program parallel

integer :: a,b,c
integer :: num_threads

a = 1
b = 2
!FIRDialect: %[[VAR_A:.*]] = fir.alloca i32 {name = "a"}
!FIRDialect: %[[VAR_B:.*]] = fir.alloca i32 {name = "b"}
!FIRDialect: %[[VAR_C:.*]] = fir.alloca i32 {name = "c"}
!FIRDialect: %[[VAR_NUM_THREADS:.*]] = fir.alloca i32 {name = "num_threads"}

!LLVMIRDialect: %[[VAR_A:.*]] = llvm.alloca %{{.*}} x !llvm.i32 {in_type = i32, name = "a"}
!LLVMIRDialect: %[[VAR_B:.*]] = llvm.alloca %{{.*}} x !llvm.i32 {in_type = i32, name = "b"}
!LLVMIRDialect: %[[VAR_C:.*]] = llvm.alloca %{{.*}} x !llvm.i32 {in_type = i32, name = "c"}
!LLVMIRDialect: %[[VAR_NUM_THREADS:.*]] = llvm.alloca %{{.*}} x !llvm.i32 {in_type = i32, name = "num_threads"}

!LLVMIR: %[[OMP_GLOBAL_THREAD_NUM:.*]] = call i32 @__kmpc_global_thread_num(%struct.ident_t* @{{.*}})
!LLVMIR: call void @__kmpc_push_num_threads(%struct.ident_t* @{{.*}}, i32 %[[OMP_GLOBAL_THREAD_NUM]], i32 %{{.*}})

!$OMP PARALLEL NUM_THREADS(num_threads)
!FIRDialect: omp.parallel num_threads(%{{.*}} : i32) {
!FIRDialect-DAG: %[[OMP_VAR_A:.*]] = fir.load %[[VAR_A]]
!FIRDialect-DAG: %[[OMP_VAR_B:.*]] = fir.load %[[VAR_B]]
!FIRDialect: %[[OMP_VAR_C:.*]] = addi %[[OMP_VAR_A]], %[[OMP_VAR_B]]
!FIRDialect: fir.store %[[OMP_VAR_C]] to %[[VAR_C]]
!FIRDialect: %[[CONSTANT:.*]] = constant 4 : i32
!FIRDialect: %[[COND_C:.*]] = fir.load %[[VAR_C]] : !fir.ref<i32>
!FIRDialect: %[[COND_RES:.*]] = cmpi "sgt", %[[COND_C]], %[[CONSTANT]] : i32
!FIRDialect: fir.if %[[COND_RES]] {
!FIRDialect: fir.call @_FortranAioBeginExternalListOutput
!FIRDialect: fir.call @_FortranAioOutputAscii
!FIRDialect: fir.call @_FortranAioEndIoStatement
!FIRDialect: } else {
!FIRDialect-NEXT: }
!FIRDialect: fir.call @_FortranAioBeginExternalListOutput
!FIRDialect: fir.load %[[VAR_C]]
!FIRDialect: fir.call @_FortranAioOutputInteger64
!FIRDialect: fir.call @_FortranAioEndIoStatement
!FIRDialect: omp.terminator
!FIRDialect-NEXT: }

!LLVMIRDialect-LABEL: omp.parallel num_threads(%{{.*}} : !llvm.i32) {
!LLVMIRDialect-DAG: %[[OMP_VAR_A:.*]] = llvm.load %[[VAR_A:.*]]
!LLVMIRDialect-DAG: %[[OMP_VAR_B:.*]] = llvm.load %[[VAR_B:.*]]
!LLVMIRDialect: %[[OMP_VAR_C:.*]] = llvm.add %[[OMP_VAR_B]], %[[OMP_VAR_A]]
!LLVMIRDialect: llvm.store %[[OMP_VAR_C]], %[[VAR_C]]
!LLVMIRDialect: %[[COND_C:.*]] = llvm.load %[[VAR_C]] : !llvm.ptr<i32>
!LLVMIRDialect: %[[COND_RES:.*]] = llvm.icmp "sgt" %[[COND_C]], %{{.*}} : !llvm.i32
!LLVMIRDialect: llvm.cond_br %[[COND_RES]], ^bb1, ^bb2
!LLVMIRDialect: ^bb1: // pred: ^bb0
!LLVMIRDialect: llvm.call @_FortranAioBeginExternalListOutput
!LLVMIRDialect: llvm.call @_FortranAioOutputAscii
!LLVMIRDialect: llvm.call @_FortranAioEndIoStatement
!LLVMIRDialect: llvm.br ^bb2
!LLVMIRDialect: ^bb2: // 2 preds: ^bb0, ^bb1
!LLVMIRDialect: llvm.call @_FortranAioBeginExternalListOutput
!LLVMIRDialect: llvm.load %[[VAR_C]] : !llvm.ptr<i32>
!LLVMIRDialect: llvm.call @_FortranAioOutputInteger64
!LLVMIRDialect: llvm.call @_FortranAioEndIoStatement
!LLVMIRDialect: omp.terminator
!LLVMIRDialect-NEXT: }

!LLVMIR: call {{.*}} @__kmpc_fork_call(%struct.ident_t* @{{.*}} @_QQmain..omp_par

!LLVMIR-LABEL: define internal void @_QQmain..omp_par
!LLVMIR: br label %[[REGION_1:.*]]
!LLVMIR: [[REGION_1]]:
!LLVMIR: br label %[[REGION_1_1:.*]]
!LLVMIR: [[REGION_1_1]]:
!LLVMIR: %[[COND_RES:.*]] = icmp sgt i32 %{{.*}}, 4
!LLVMIR: br i1 %[[COND_RES]], label %{{.*}}, label %{{.*}}
!LLVMIR: call i8* @_FortranAioBeginExternalListOutput
!LLVMIR: call i1 @_FortranAioOutputInteger64
!LLVMIR: call i32 @_FortranAioEndIoStatement
c = a + b

if (c .gt. 4) then
print*, "Inside If Statement"
endif

print*, c

!$OMP END PARALLEL

!$OMP PARALLEL
print*, "Second Region"
!FIRDialect: omp.parallel {
!FIRDialect: fir.call @_FortranAioBeginExternalListOutput
!FIRDialect: fir.call @_FortranAioOutputAscii
!FIRDialect: fir.call @_FortranAioEndIoStatement
!FIRDialect: omp.terminator
!FIRDialect-NEXT: }

!LLVMIRDialect: omp.parallel {
!LLVMIRDialect: llvm.call @_FortranAioBeginExternalListOutput
!LLVMIRDialect: llvm.call @_FortranAioOutputAscii
!LLVMIRDialect: llvm.call @_FortranAioEndIoStatement
!LLVMIRDialect: omp.terminator
!LLVMIRDialect: }

!LLVMIR-DAG-LABEL: call {{.*}} @__kmpc_fork_call(%struct.ident_t* @{{.*}} @_QQmain..omp_par.1
!LLVMIR-DAG-LABEL: define internal void @_QQmain..omp_par.1
!LLVMIR: call i8* @_FortranAioBeginExternalListOutput
!LLVMIR: call i32 @_FortranAioEndIoStatement
!$OMP END PARALLEL

end program