[Mlir-commits] [mlir] [MLIR][OpenMP] Extend omp.private materialization support: `firstprivate` (PR #82164)

Kareem Ergawy llvmlistbot at llvm.org
Sun Feb 18 04:56:44 PST 2024


https://github.com/ergawy created https://github.com/llvm/llvm-project/pull/82164

Extends current support for delayed privatization during translation to
LLVM IR. This adds support for one-block `firstprivate` `omp.private`
ops.

### This is a follow-up to 81715, only the commit with the same name as the PR title is relevant.

>From 9f78a93b307923dc2620626ff6b4b095250d5406 Mon Sep 17 00:00:00 2001
From: ergawy <kareem.ergawy at amd.com>
Date: Tue, 13 Feb 2024 04:46:50 -0600
Subject: [PATCH 1/2] [MLIR][OpenMP] Support basic materialization for
 `omp.private` ops

Adds basic support for materializing delayed privatization. So far, the
restrictions on the implementation are:
- Only `private` clauses are supported (`firstprivate` support will be
  added in a later PR).
- Only single-block `omp.private -> alloc` regions are supported
  (multi-block ones will be supported in a later PR).
---
 .../OpenMP/OpenMPToLLVMIRTranslation.cpp      | 155 +++++++++++++++---
 mlir/test/Target/LLVMIR/openmp-private.mlir   |  91 ++++++++++
 2 files changed, 227 insertions(+), 19 deletions(-)
 create mode 100644 mlir/test/Target/LLVMIR/openmp-private.mlir

diff --git a/mlir/lib/Target/LLVMIR/Dialect/OpenMP/OpenMPToLLVMIRTranslation.cpp b/mlir/lib/Target/LLVMIR/Dialect/OpenMP/OpenMPToLLVMIRTranslation.cpp
index 78a2ad76a1e3b8..484fd7e6f6c46d 100644
--- a/mlir/lib/Target/LLVMIR/Dialect/OpenMP/OpenMPToLLVMIRTranslation.cpp
+++ b/mlir/lib/Target/LLVMIR/Dialect/OpenMP/OpenMPToLLVMIRTranslation.cpp
@@ -1000,11 +1000,39 @@ convertOmpWsLoop(Operation &opInst, llvm::IRBuilderBase &builder,
   return success();
 }
 
+/// Replace the region arguments of the parallel op (which correspond to private
+/// variables) with the actual private varibles they correspond to. This
+/// prepares the parallel op so that it matches what is expected by the
+/// OMPIRBuilder. Instead of editing the original op in-place, this function
+/// does the required changes to a cloned version which should then be erased by
+/// the caller.
+static omp::ParallelOp
+prepareOmpParallelForPrivatization(omp::ParallelOp opInst) {
+  mlir::OpBuilder cloneBuilder(opInst);
+  omp::ParallelOp opInstClone =
+      llvm::cast<omp::ParallelOp>(cloneBuilder.clone(*opInst));
+
+  Region &region = opInstClone.getRegion();
+  auto privateVars = opInstClone.getPrivateVars();
+
+  auto privateVarsIt = privateVars.begin();
+  // Reduction precede private arguments, so skip them first.
+  unsigned privateArgBeginIdx = opInstClone.getNumReductionVars();
+  unsigned privateArgEndIdx = privateArgBeginIdx + privateVars.size();
+  for (size_t argIdx = privateArgBeginIdx; argIdx < privateArgEndIdx;
+       ++argIdx, ++privateVarsIt)
+    replaceAllUsesInRegionWith(region.getArgument(argIdx), *privateVarsIt,
+                               region);
+  return opInstClone;
+}
+
 /// Converts the OpenMP parallel operation to LLVM IR.
 static LogicalResult
 convertOmpParallel(omp::ParallelOp opInst, llvm::IRBuilderBase &builder,
                    LLVM::ModuleTranslation &moduleTranslation) {
   using InsertPointTy = llvm::OpenMPIRBuilder::InsertPointTy;
+  omp::ParallelOp opInstClone = prepareOmpParallelForPrivatization(opInst);
+
   // TODO: support error propagation in OpenMPIRBuilder and use it instead of
   // relying on captured variables.
   LogicalResult bodyGenStatus = success();
@@ -1013,12 +1041,12 @@ convertOmpParallel(omp::ParallelOp opInst, llvm::IRBuilderBase &builder,
   auto bodyGenCB = [&](InsertPointTy allocaIP, InsertPointTy codeGenIP) {
     // Collect reduction declarations
     SmallVector<omp::ReductionDeclareOp> reductionDecls;
-    collectReductionDecls(opInst, reductionDecls);
+    collectReductionDecls(opInstClone, reductionDecls);
 
     // Allocate reduction vars
     SmallVector<llvm::Value *> privateReductionVariables;
     DenseMap<Value, llvm::Value *> reductionVariableMap;
-    allocReductionVars(opInst, builder, moduleTranslation, allocaIP,
+    allocReductionVars(opInstClone, builder, moduleTranslation, allocaIP,
                        reductionDecls, privateReductionVariables,
                        reductionVariableMap);
 
@@ -1030,7 +1058,7 @@ convertOmpParallel(omp::ParallelOp opInst, llvm::IRBuilderBase &builder,
 
     // Initialize reduction vars
     builder.restoreIP(allocaIP);
-    for (unsigned i = 0; i < opInst.getNumReductionVars(); ++i) {
+    for (unsigned i = 0; i < opInstClone.getNumReductionVars(); ++i) {
       SmallVector<llvm::Value *> phis;
       if (failed(inlineConvertOmpRegions(
               reductionDecls[i].getInitializerRegion(), "omp.reduction.neutral",
@@ -1051,18 +1079,19 @@ convertOmpParallel(omp::ParallelOp opInst, llvm::IRBuilderBase &builder,
     // ParallelOp has only one region associated with it.
     builder.restoreIP(codeGenIP);
     auto regionBlock =
-        convertOmpOpRegions(opInst.getRegion(), "omp.par.region", builder,
+        convertOmpOpRegions(opInstClone.getRegion(), "omp.par.region", builder,
                             moduleTranslation, bodyGenStatus);
 
     // Process the reductions if required.
-    if (opInst.getNumReductionVars() > 0) {
+    if (opInstClone.getNumReductionVars() > 0) {
       // Collect reduction info
       SmallVector<OwningReductionGen> owningReductionGens;
       SmallVector<OwningAtomicReductionGen> owningAtomicReductionGens;
       SmallVector<llvm::OpenMPIRBuilder::ReductionInfo> reductionInfos;
-      collectReductionInfo(opInst, builder, moduleTranslation, reductionDecls,
-                           owningReductionGens, owningAtomicReductionGens,
-                           privateReductionVariables, reductionInfos);
+      collectReductionInfo(opInstClone, builder, moduleTranslation,
+                           reductionDecls, owningReductionGens,
+                           owningAtomicReductionGens, privateReductionVariables,
+                           reductionInfos);
 
       // Move to region cont block
       builder.SetInsertPoint(regionBlock->getTerminator());
@@ -1075,7 +1104,8 @@ convertOmpParallel(omp::ParallelOp opInst, llvm::IRBuilderBase &builder,
           ompBuilder->createReductions(builder.saveIP(), allocaIP,
                                        reductionInfos, false);
       if (!contInsertPoint.getBlock()) {
-        bodyGenStatus = opInst->emitOpError() << "failed to convert reductions";
+        bodyGenStatus = opInstClone->emitOpError()
+                        << "failed to convert reductions";
         return;
       }
 
@@ -1086,12 +1116,97 @@ convertOmpParallel(omp::ParallelOp opInst, llvm::IRBuilderBase &builder,
 
   // TODO: Perform appropriate actions according to the data-sharing
   // attribute (shared, private, firstprivate, ...) of variables.
-  // Currently defaults to shared.
+  // Currently shared and private are supported.
   auto privCB = [&](InsertPointTy allocaIP, InsertPointTy codeGenIP,
                     llvm::Value &, llvm::Value &vPtr,
                     llvm::Value *&replacementValue) -> InsertPointTy {
     replacementValue = &vPtr;
 
+    // If this is a private value, this lambda will return the corresponding
+    // mlir value and its `PrivateClauseOp`. Otherwise, empty values are
+    // returned.
+    auto [privVar, privatizerClone] =
+        [&]() -> std::pair<mlir::Value, omp::PrivateClauseOp> {
+      if (!opInstClone.getPrivateVars().empty()) {
+        auto privVars = opInstClone.getPrivateVars();
+        auto privatizers = opInstClone.getPrivatizers();
+
+        for (auto [privVar, privatizerAttr] :
+             llvm::zip_equal(privVars, *privatizers)) {
+          // Find the MLIR private variable corresponding to the LLVM value
+          // being privatized.
+          llvm::Value *llvmPrivVar = moduleTranslation.lookupValue(privVar);
+          if (llvmPrivVar != &vPtr)
+            continue;
+
+          SymbolRefAttr privSym = llvm::cast<SymbolRefAttr>(privatizerAttr);
+          omp::PrivateClauseOp privatizer =
+              SymbolTable::lookupNearestSymbolFrom<omp::PrivateClauseOp>(
+                  opInstClone, privSym);
+
+          // Clone the privatizer in case it used by more than one parallel
+          // region. The privatizer is processed in-place (see below) before it
+          // gets inlined in the parallel region and therefore processing the
+          // original op is dangerous.
+          return {privVar, privatizer.clone()};
+        }
+      }
+
+      return {mlir::Value(), omp::PrivateClauseOp()};
+    }();
+
+    if (privVar) {
+      if (privatizerClone.getDataSharingType() ==
+          omp::DataSharingClauseType::FirstPrivate) {
+        privatizerClone.emitOpError(
+            "TODO: delayed privatization is not "
+            "supported for `firstprivate` clauses yet.");
+        bodyGenStatus = failure();
+        return codeGenIP;
+      }
+
+      Region &allocRegion = privatizerClone.getAllocRegion();
+
+      if (!allocRegion.hasOneBlock()) {
+        privatizerClone.emitOpError(
+            "TODO: multi-block alloc regions are not supported yet.");
+        bodyGenStatus = failure();
+        return codeGenIP;
+      }
+
+      // Replace the privatizer block argument with mlir value being privatized.
+      // This way, the body of the privatizer will be changed from using the
+      // region/block argument to the value being privatized.
+      auto allocRegionArg = allocRegion.getArgument(0);
+      replaceAllUsesInRegionWith(allocRegionArg, privVar, allocRegion);
+
+      auto oldIP = builder.saveIP();
+      builder.restoreIP(allocaIP);
+
+      // Temporarily unlink the terminator from its parent since
+      // `inlineConvertOmpRegions` expects the insertion block to **not**
+      // contain a terminator.
+      llvm::Instruction &allocaTerminator = builder.GetInsertBlock()->back();
+      assert(allocaTerminator.isTerminator());
+      allocaTerminator.removeFromParent();
+
+      SmallVector<llvm::Value *, 1> yieldedValues;
+      if (failed(inlineConvertOmpRegions(allocRegion, "omp.privatizer", builder,
+                                         moduleTranslation, &yieldedValues))) {
+        opInstClone.emitError(
+            "failed to inline `alloc` region of an `omp.private` "
+            "op in the parallel region");
+        bodyGenStatus = failure();
+      } else {
+        assert(yieldedValues.size() == 1);
+        replacementValue = yieldedValues.front();
+      }
+
+      allocaTerminator.insertAfter(&builder.GetInsertBlock()->back());
+      privatizerClone.erase();
+      builder.restoreIP(oldIP);
+    }
+
     return codeGenIP;
   };
 
@@ -1100,13 +1215,13 @@ convertOmpParallel(omp::ParallelOp opInst, llvm::IRBuilderBase &builder,
   auto finiCB = [&](InsertPointTy codeGenIP) {};
 
   llvm::Value *ifCond = nullptr;
-  if (auto ifExprVar = opInst.getIfExprVar())
+  if (auto ifExprVar = opInstClone.getIfExprVar())
     ifCond = moduleTranslation.lookupValue(ifExprVar);
   llvm::Value *numThreads = nullptr;
-  if (auto numThreadsVar = opInst.getNumThreadsVar())
+  if (auto numThreadsVar = opInstClone.getNumThreadsVar())
     numThreads = moduleTranslation.lookupValue(numThreadsVar);
   auto pbKind = llvm::omp::OMP_PROC_BIND_default;
-  if (auto bind = opInst.getProcBindVal())
+  if (auto bind = opInstClone.getProcBindVal())
     pbKind = getProcBindKind(*bind);
   // TODO: Is the Parallel construct cancellable?
   bool isCancellable = false;
@@ -1119,6 +1234,7 @@ convertOmpParallel(omp::ParallelOp opInst, llvm::IRBuilderBase &builder,
       ompBuilder->createParallel(ompLoc, allocaIP, bodyGenCB, privCB, finiCB,
                                  ifCond, numThreads, pbKind, isCancellable));
 
+  opInstClone.erase();
   return bodyGenStatus;
 }
 
@@ -3009,12 +3125,13 @@ LogicalResult OpenMPDialectLLVMIRTranslationInterface::convertOperation(
       .Case([&](omp::TargetOp) {
         return convertOmpTarget(*op, builder, moduleTranslation);
       })
-      .Case<omp::MapInfoOp, omp::DataBoundsOp>([&](auto op) {
-        // No-op, should be handled by relevant owning operations e.g.
-        // TargetOp, EnterDataOp, ExitDataOp, DataOp etc. and then
-        // discarded
-        return success();
-      })
+      .Case<omp::MapInfoOp, omp::DataBoundsOp, omp::PrivateClauseOp>(
+          [&](auto op) {
+            // No-op, should be handled by relevant owning operations e.g.
+            // TargetOp, EnterDataOp, ExitDataOp, DataOp etc. and then
+            // discarded
+            return success();
+          })
       .Default([&](Operation *inst) {
         return inst->emitError("unsupported OpenMP operation: ")
                << inst->getName();
diff --git a/mlir/test/Target/LLVMIR/openmp-private.mlir b/mlir/test/Target/LLVMIR/openmp-private.mlir
new file mode 100644
index 00000000000000..1ac87852d5300f
--- /dev/null
+++ b/mlir/test/Target/LLVMIR/openmp-private.mlir
@@ -0,0 +1,91 @@
+// Test code-gen for `omp.parallel` ops with delayed privatizers (i.e. using
+// `omp.private` ops).
+
+// RUN: mlir-translate -mlir-to-llvmir -split-input-file %s | FileCheck %s
+
+llvm.func @parallel_op_1_private(%arg0: !llvm.ptr) {
+  omp.parallel private(@x.privatizer %arg0 -> %arg2 : !llvm.ptr) {
+    %0 = llvm.load %arg2 : !llvm.ptr -> f32
+    omp.terminator
+  }
+  llvm.return
+}
+
+// CHECK-LABEL: @parallel_op_1_private
+// CHECK-SAME: (ptr %[[ORIG:.*]]) {
+// CHECK: %[[OMP_PAR_ARG:.*]] = alloca { ptr }, align 8
+// CHECK: %[[ORIG_GEP:.*]] = getelementptr { ptr }, ptr %[[OMP_PAR_ARG]], i32 0, i32 0
+// CHECK: store ptr %[[ORIG]], ptr %[[ORIG_GEP]], align 8
+// CHECK: call void (ptr, i32, ptr, ...) @__kmpc_fork_call(ptr @1, i32 1, ptr @parallel_op_1_private..omp_par, ptr %[[OMP_PAR_ARG]])
+// CHECK: }
+
+// CHECK-LABEL: void @parallel_op_1_private..omp_par
+// CHECK-SAME: (ptr noalias %{{.*}}, ptr noalias %{{.*}}, ptr %[[ARG:.*]])
+// CHECK: %[[ORIG_PTR_PTR:.*]] = getelementptr { ptr }, ptr %[[ARG]], i32 0, i32 0
+// CHECK: %[[ORIG_PTR:.*]] = load ptr, ptr %[[ORIG_PTR_PTR]], align 8
+
+// Check that the privatizer alloc region was inlined properly.
+// CHECK: %[[PRIV_ALLOC:.*]] = alloca float, align 4
+// CHECK: %[[ORIG_VAL:.*]] = load float, ptr %[[ORIG_PTR]], align 4
+// CHECK: store float %[[ORIG_VAL]], ptr %[[PRIV_ALLOC]], align 4
+// CHECK-NEXT: br
+
+// Check that the privatized value is used (rather than the original one).
+// CHECK: load float, ptr %[[PRIV_ALLOC]], align 4
+// CHECK: }
+
+llvm.func @parallel_op_2_privates(%arg0: !llvm.ptr, %arg1: !llvm.ptr) {
+  omp.parallel private(@x.privatizer %arg0 -> %arg2 : !llvm.ptr, @y.privatizer %arg1 -> %arg3 : !llvm.ptr) {
+    %0 = llvm.load %arg2 : !llvm.ptr -> f32
+    %1 = llvm.load %arg3 : !llvm.ptr -> i32
+    omp.terminator
+  }
+  llvm.return
+}
+
+// CHECK-LABEL: @parallel_op_2_privates
+// CHECK-SAME: (ptr %[[ORIG1:.*]], ptr %[[ORIG2:.*]]) {
+// CHECK: %[[OMP_PAR_ARG:.*]] = alloca { ptr, ptr }, align 8
+// CHECK: %[[ORIG1_GEP:.*]] = getelementptr { ptr, ptr }, ptr %[[OMP_PAR_ARG]], i32 0, i32 0
+// CHECK: store ptr %[[ORIG1]], ptr %[[ORIG1_GEP]], align 8
+// CHECK: call void (ptr, i32, ptr, ...) @__kmpc_fork_call(ptr @1, i32 1, ptr @parallel_op_2_privates..omp_par, ptr %[[OMP_PAR_ARG]])
+// CHECK: }
+
+// CHECK-LABEL: void @parallel_op_2_privates..omp_par
+// CHECK-SAME: (ptr noalias %{{.*}}, ptr noalias %{{.*}}, ptr %[[ARG:.*]])
+// CHECK: %[[ORIG1_PTR_PTR:.*]] = getelementptr { ptr, ptr }, ptr %[[ARG]], i32 0, i32 0
+// CHECK: %[[ORIG1_PTR:.*]] = load ptr, ptr %[[ORIG1_PTR_PTR]], align 8
+// CHECK: %[[ORIG2_PTR_PTR:.*]] = getelementptr { ptr, ptr }, ptr %[[ARG]], i32 0, i32 1
+// CHECK: %[[ORIG2_PTR:.*]] = load ptr, ptr %[[ORIG2_PTR_PTR]], align 8
+
+// Check that the privatizer alloc region was inlined properly.
+// CHECK: %[[PRIV1_ALLOC:.*]] = alloca float, align 4
+// CHECK: %[[ORIG1_VAL:.*]] = load float, ptr %[[ORIG1_PTR]], align 4
+// CHECK: store float %[[ORIG1_VAL]], ptr %[[PRIV1_ALLOC]], align 4
+// CHECK: %[[PRIV2_ALLOC:.*]] = alloca i32, align 4
+// CHECK: %[[ORIG2_VAL:.*]] = load i32, ptr %[[ORIG2_PTR]], align 4
+// CHECK: store i32 %[[ORIG2_VAL]], ptr %[[PRIV2_ALLOC]], align 4
+// CHECK-NEXT: br
+
+// Check that the privatized value is used (rather than the original one).
+// CHECK: load float, ptr %[[PRIV1_ALLOC]], align 4
+// CHECK: load i32, ptr %[[PRIV2_ALLOC]], align 4
+// CHECK: }
+
+omp.private {type = private} @x.privatizer : !llvm.ptr alloc {
+^bb0(%arg0: !llvm.ptr):
+  %c1 = llvm.mlir.constant(1 : i32) : i32
+  %0 = llvm.alloca %c1 x f32 : (i32) -> !llvm.ptr
+  %1 = llvm.load %arg0 : !llvm.ptr -> f32
+  llvm.store %1, %0 : f32, !llvm.ptr
+  omp.yield(%0 : !llvm.ptr)
+}
+
+omp.private {type = private} @y.privatizer : !llvm.ptr alloc {
+^bb0(%arg0: !llvm.ptr):
+  %c1 = llvm.mlir.constant(1 : i32) : i32
+  %0 = llvm.alloca %c1 x i32 : (i32) -> !llvm.ptr
+  %1 = llvm.load %arg0 : !llvm.ptr -> i32
+  llvm.store %1, %0 : i32, !llvm.ptr
+  omp.yield(%0 : !llvm.ptr)
+}

>From 2153390628fd813bd2db6dd37b888f8382e7b064 Mon Sep 17 00:00:00 2001
From: ergawy <kareem.ergawy at amd.com>
Date: Sun, 18 Feb 2024 06:50:38 -0600
Subject: [PATCH 2/2] [MLIR][OpenMP] Extend `omp.private` materialization
 support: `firstprivate`

Extends current support for delayed privatization during translation to
LLVM IR. This adds support for one-block `firstprivate` `omp.private`
ops.
---
 .../OpenMP/OpenMPToLLVMIRTranslation.cpp      | 46 +++++++++++++----
 .../Target/LLVMIR/openmp-firstprivate.mlir    | 50 +++++++++++++++++++
 2 files changed, 87 insertions(+), 9 deletions(-)
 create mode 100644 mlir/test/Target/LLVMIR/openmp-firstprivate.mlir

diff --git a/mlir/lib/Target/LLVMIR/Dialect/OpenMP/OpenMPToLLVMIRTranslation.cpp b/mlir/lib/Target/LLVMIR/Dialect/OpenMP/OpenMPToLLVMIRTranslation.cpp
index 484fd7e6f6c46d..b41c27b1e14ba2 100644
--- a/mlir/lib/Target/LLVMIR/Dialect/OpenMP/OpenMPToLLVMIRTranslation.cpp
+++ b/mlir/lib/Target/LLVMIR/Dialect/OpenMP/OpenMPToLLVMIRTranslation.cpp
@@ -1156,15 +1156,6 @@ convertOmpParallel(omp::ParallelOp opInst, llvm::IRBuilderBase &builder,
     }();
 
     if (privVar) {
-      if (privatizerClone.getDataSharingType() ==
-          omp::DataSharingClauseType::FirstPrivate) {
-        privatizerClone.emitOpError(
-            "TODO: delayed privatization is not "
-            "supported for `firstprivate` clauses yet.");
-        bodyGenStatus = failure();
-        return codeGenIP;
-      }
-
       Region &allocRegion = privatizerClone.getAllocRegion();
 
       if (!allocRegion.hasOneBlock()) {
@@ -1174,6 +1165,43 @@ convertOmpParallel(omp::ParallelOp opInst, llvm::IRBuilderBase &builder,
         return codeGenIP;
       }
 
+      // If this is a `firstprivate` clause, prepare the `omp.private` op by:
+      if (privatizerClone.getDataSharingType() ==
+          omp::DataSharingClauseType::FirstPrivate) {
+        auto oldAllocBackBlock = std::prev(allocRegion.end());
+        omp::YieldOp oldAllockYieldOp =
+            llvm::cast<omp::YieldOp>(oldAllocBackBlock->getTerminator());
+
+        Region &copyRegion = privatizerClone.getCopyRegion();
+
+        if (!copyRegion.hasOneBlock()) {
+          privatizerClone.emitOpError(
+              "TODO: multi-block copy regions are not supported yet.");
+          bodyGenStatus = failure();
+          return codeGenIP;
+        }
+
+        mlir::IRRewriter copyCloneBuilder(&moduleTranslation.getContext());
+        // 1. Cloning the `copy` region to the end of the `alloc` region.
+        copyCloneBuilder.cloneRegionBefore(copyRegion, allocRegion,
+                                           allocRegion.end());
+
+        auto newCopyRegionFrontBlock = std::next(oldAllocBackBlock);
+        // 2. Merging the last `alloc` block with the first block in the `copy`
+        // region clone.
+        // 3. Re-mapping the first argument of the `copy` region to be the
+        // argument of the `alloc` region and the second argument of the `copy`
+        // region to be the yielded value of the `alloc` region (this is the
+        // private clone of the privatized value).
+        copyCloneBuilder.mergeBlocks(
+            &*newCopyRegionFrontBlock, &*oldAllocBackBlock,
+            {allocRegion.getArgument(0), oldAllockYieldOp.getOperand(0)});
+
+        // 4. The old terminator of the `alloc` region is not needed anymore, so
+        // delete it.
+        oldAllockYieldOp.erase();
+      }
+
       // Replace the privatizer block argument with mlir value being privatized.
       // This way, the body of the privatizer will be changed from using the
       // region/block argument to the value being privatized.
diff --git a/mlir/test/Target/LLVMIR/openmp-firstprivate.mlir b/mlir/test/Target/LLVMIR/openmp-firstprivate.mlir
new file mode 100644
index 00000000000000..54b8dfc85ccc22
--- /dev/null
+++ b/mlir/test/Target/LLVMIR/openmp-firstprivate.mlir
@@ -0,0 +1,50 @@
+// Test code-gen for `omp.parallel` ops with delayed privatizers (i.e. using
+// `omp.private` ops).
+
+// RUN: mlir-translate -mlir-to-llvmir -split-input-file %s | FileCheck %s
+
+llvm.func @parallel_op_firstprivate(%arg0: !llvm.ptr) {
+  omp.parallel private(@x.privatizer %arg0 -> %arg2 : !llvm.ptr) {
+    %0 = llvm.load %arg2 : !llvm.ptr -> f32
+    omp.terminator
+  }
+  llvm.return
+}
+
+omp.private {type = firstprivate} @x.privatizer : !llvm.ptr alloc {
+^bb0(%arg0: !llvm.ptr):
+  %c1 = llvm.mlir.constant(1 : i32) : i32
+  %0 = llvm.alloca %c1 x f32 : (i32) -> !llvm.ptr
+  omp.yield(%0 : !llvm.ptr)
+} copy {
+^bb0(%arg0: !llvm.ptr, %arg1: !llvm.ptr):
+  %0 = llvm.load %arg0 : !llvm.ptr -> f32
+  llvm.store %0, %arg1 : f32, !llvm.ptr
+  omp.yield(%arg1 : !llvm.ptr)
+}
+
+// CHECK-LABEL: @parallel_op_firstprivate
+// CHECK-SAME: (ptr %[[ORIG:.*]]) {
+// CHECK: %[[OMP_PAR_ARG:.*]] = alloca { ptr }, align 8
+// CHECK: %[[ORIG_GEP:.*]] = getelementptr { ptr }, ptr %[[OMP_PAR_ARG]], i32 0, i32 0
+// CHECK: store ptr %[[ORIG]], ptr %[[ORIG_GEP]], align 8
+// CHECK: call void (ptr, i32, ptr, ...) @__kmpc_fork_call(ptr @1, i32 1, ptr @parallel_op_firstprivate..omp_par, ptr %[[OMP_PAR_ARG]])
+// CHECK: }
+
+// CHECK-LABEL: void @parallel_op_firstprivate..omp_par
+// CHECK-SAME: (ptr noalias %{{.*}}, ptr noalias %{{.*}}, ptr %[[ARG:.*]])
+// CHECK: %[[ORIG_PTR_PTR:.*]] = getelementptr { ptr }, ptr %[[ARG]], i32 0, i32 0
+// CHECK: %[[ORIG_PTR:.*]] = load ptr, ptr %[[ORIG_PTR_PTR]], align 8
+
+// Check that the privatizer alloc region was inlined properly.
+// CHECK: %[[PRIV_ALLOC:.*]] = alloca float, align 4
+
+// Check that the privatizer copy region was inlined properly.
+
+// CHECK: %[[ORIG_VAL:.*]] = load float, ptr %[[ORIG_PTR]], align 4
+// CHECK: store float %[[ORIG_VAL]], ptr %[[PRIV_ALLOC]], align 4
+// CHECK-NEXT: br
+
+// Check that the privatized value is used (rather than the original one).
+// CHECK: load float, ptr %[[PRIV_ALLOC]], align 4
+// CHECK: }



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