Index: lib/CodeGen/CGOpenMPRuntime.h
===================================================================
--- lib/CodeGen/CGOpenMPRuntime.h
+++ lib/CodeGen/CGOpenMPRuntime.h
@@ -893,6 +893,27 @@
OpenMPDirectiveKind InnermostKind,
const RegionCodeGenTy &CodeGen,
bool HasCancel = false);
+
+ /// Emits reduction function.
+ /// \param ArgsType Array type containing pointers to reduction variables.
+ /// \param Privates List of private copies for original reduction arguments.
+ /// \param LHSExprs List of LHS in \a ReductionOps reduction operations.
+ /// \param RHSExprs List of RHS in \a ReductionOps reduction operations.
+ /// \param ReductionOps List of reduction operations in form 'LHS binop RHS'
+ /// or 'operator binop(LHS, RHS)'.
+ llvm::Value *emitReductionFunction(CodeGenModule &CGM, llvm::Type *ArgsType,
+ ArrayRef<const Expr *> Privates,
+ ArrayRef<const Expr *> LHSExprs,
+ ArrayRef<const Expr *> RHSExprs,
+ ArrayRef<const Expr *> ReductionOps);
+
+ /// Emits single reduction combiner
+ void emitSingleReductionCombiner(CodeGenFunction &CGF,
+ const Expr *ReductionOp,
+ const Expr *PrivateRef,
+ const DeclRefExpr *LHS,
+ const DeclRefExpr *RHS);
+
/// \brief Emit a code for reduction clause. Next code should be emitted for
/// reduction:
/// \code
@@ -931,12 +952,14 @@
/// or 'operator binop(LHS, RHS)'.
/// \param WithNowait true if parent directive has also nowait clause, false
/// otherwise.
+ /// \param ReductionKind The kind of reduction to perform.
virtual void emitReduction(CodeGenFunction &CGF, SourceLocation Loc,
ArrayRef<const Expr *> Privates,
ArrayRef<const Expr *> LHSExprs,
ArrayRef<const Expr *> RHSExprs,
ArrayRef<const Expr *> ReductionOps,
- bool WithNowait, bool SimpleReduction);
+ bool WithNowait, bool SimpleReduction,
+ OpenMPDirectiveKind ReductionKind);
/// \brief Emit code for 'taskwait' directive.
virtual void emitTaskwaitCall(CodeGenFunction &CGF, SourceLocation Loc);
Index: lib/CodeGen/CGOpenMPRuntime.cpp
===================================================================
--- lib/CodeGen/CGOpenMPRuntime.cpp
+++ lib/CodeGen/CGOpenMPRuntime.cpp
@@ -4257,12 +4257,10 @@
CGF.EmitIgnoredExpr(ReductionOp);
}
-static llvm::Value *emitReductionFunction(CodeGenModule &CGM,
- llvm::Type *ArgsType,
- ArrayRef<const Expr *> Privates,
- ArrayRef<const Expr *> LHSExprs,
- ArrayRef<const Expr *> RHSExprs,
- ArrayRef<const Expr *> ReductionOps) {
+llvm::Value *CGOpenMPRuntime::emitReductionFunction(
+ CodeGenModule &CGM, llvm::Type *ArgsType, ArrayRef<const Expr *> Privates,
+ ArrayRef<const Expr *> LHSExprs, ArrayRef<const Expr *> RHSExprs,
+ ArrayRef<const Expr *> ReductionOps) {
auto &C = CGM.getContext();
// void reduction_func(void *LHSArg, void *RHSArg);
@@ -4345,11 +4343,11 @@
return Fn;
}
-static void emitSingleReductionCombiner(CodeGenFunction &CGF,
- const Expr *ReductionOp,
- const Expr *PrivateRef,
- const DeclRefExpr *LHS,
- const DeclRefExpr *RHS) {
+void CGOpenMPRuntime::emitSingleReductionCombiner(CodeGenFunction &CGF,
+ const Expr *ReductionOp,
+ const Expr *PrivateRef,
+ const DeclRefExpr *LHS,
+ const DeclRefExpr *RHS) {
if (PrivateRef->getType()->isArrayType()) {
// Emit reduction for array section.
auto *LHSVar = cast<VarDecl>(LHS->getDecl());
@@ -4369,7 +4367,8 @@
ArrayRef<const Expr *> LHSExprs,
ArrayRef<const Expr *> RHSExprs,
ArrayRef<const Expr *> ReductionOps,
- bool WithNowait, bool SimpleReduction) {
+ bool WithNowait, bool SimpleReduction,
+ OpenMPDirectiveKind ReductionKind) {
if (!CGF.HaveInsertPoint())
return;
// Next code should be emitted for reduction:
@@ -4513,12 +4512,13 @@
};
auto &&CodeGen = [&Privates, &LHSExprs, &RHSExprs, &ReductionOps](
CodeGenFunction &CGF, PrePostActionTy &Action) {
+ auto &RT = CGF.CGM.getOpenMPRuntime();
auto IPriv = Privates.begin();
auto ILHS = LHSExprs.begin();
auto IRHS = RHSExprs.begin();
for (auto *E : ReductionOps) {
- emitSingleReductionCombiner(CGF, E, *IPriv, cast<DeclRefExpr>(*ILHS),
- cast<DeclRefExpr>(*IRHS));
+ RT.emitSingleReductionCombiner(CGF, E, *IPriv, cast<DeclRefExpr>(*ILHS),
+ cast<DeclRefExpr>(*IRHS));
++IPriv;
++ILHS;
++IRHS;
Index: lib/CodeGen/CGOpenMPRuntimeNVPTX.h
===================================================================
--- lib/CodeGen/CGOpenMPRuntimeNVPTX.h
+++ lib/CodeGen/CGOpenMPRuntimeNVPTX.h
@@ -67,12 +67,6 @@
/// \brief Signal termination of Spmd mode execution.
void emitSpmdEntryFooter(CodeGenFunction &CGF, EntryFunctionState &EST);
- /// \brief Returns specified OpenMP runtime function for the current OpenMP
- /// implementation. Specialized for the NVPTX device.
- /// \param Function OpenMP runtime function.
- /// \return Specified function.
- llvm::Constant *createNVPTXRuntimeFunction(unsigned Function);
-
//
// Base class overrides.
//
@@ -248,7 +242,30 @@
ArrayRef<llvm::Value *> CapturedVars,
const Expr *IfCond) override;
-public:
+ /// \brief Emit a code for reduction clause.
+ ///
+ /// \param Privates List of private copies for original reduction arguments.
+ /// \param LHSExprs List of LHS in \a ReductionOps reduction operations.
+ /// \param RHSExprs List of RHS in \a ReductionOps reduction operations.
+ /// \param ReductionOps List of reduction operations in form 'LHS binop RHS'
+ /// or 'operator binop(LHS, RHS)'.
+ /// \param WithNowait true if parent directive has also nowait clause, false
+ /// otherwise.
+ /// \param ReductionKind The kind of reduction to perform.
+ virtual void emitReduction(CodeGenFunction &CGF, SourceLocation Loc,
+ ArrayRef<const Expr *> Privates,
+ ArrayRef<const Expr *> LHSExprs,
+ ArrayRef<const Expr *> RHSExprs,
+ ArrayRef<const Expr *> ReductionOps,
+ bool WithNowait, bool SimpleReduction,
+ OpenMPDirectiveKind ReductionKind) override;
+
+ /// \brief Returns specified OpenMP runtime function for the current OpenMP
+ /// implementation. Specialized for the NVPTX device.
+ /// \param Function OpenMP runtime function.
+ /// \return Specified function.
+ llvm::Constant *createNVPTXRuntimeFunction(unsigned Function);
+
/// Target codegen is specialized based on two programming models: the
/// 'generic' fork-join model of OpenMP, and a more GPU efficient 'spmd'
/// model for constructs like 'target parallel' that support it.
Index: lib/CodeGen/CGOpenMPRuntimeNVPTX.cpp
===================================================================
--- lib/CodeGen/CGOpenMPRuntimeNVPTX.cpp
+++ lib/CodeGen/CGOpenMPRuntimeNVPTX.cpp
@@ -44,6 +44,20 @@
/// Call to void __kmpc_end_serialized_parallel(ident_t *loc, kmp_int32
/// global_tid);
OMPRTL_NVPTX__kmpc_end_serialized_parallel,
+ /// \brief Call to int32_t __kmpc_shuffle_int32(int32_t element,
+ /// int16_t lane_offset, int16_t warp_size);
+ OMPRTL_NVPTX__kmpc_shuffle_int32,
+ /// \brief Call to int64_t __kmpc_shuffle_int64(int64_t element,
+ /// int16_t lane_offset, int16_t warp_size);
+ OMPRTL_NVPTX__kmpc_shuffle_int64,
+ /// \brief Call to __kmpc_nvptx_parallel_reduce_nowait(kmp_int32
+ /// global_tid, kmp_int32 num_vars, size_t reduce_size, void* reduce_data,
+ /// void (*kmp_ShuffleReductFctPtr)(void *rhsData, int16_t lane_id, int16_t
+ /// lane_offset, int16_t shortCircuit),
+ /// void (*kmp_InterWarpCopyFctPtr)(void* src, int warp_num));
+ OMPRTL_NVPTX__kmpc_parallel_reduce_nowait,
+ /// \brief Call to __kmpc_nvptx_end_reduce_nowait(int32_t global_tid);
+ OMPRTL_NVPTX__kmpc_end_reduce_nowait
};
/// Pre(post)-action for different OpenMP constructs specialized for NVPTX.
@@ -100,6 +114,25 @@
}
~ExecutionModeRAII() { Mode = SavedMode; }
};
+
+// GPU Configuration: This information can be derived from cuda registers,
+// however, providing compile time constants helps generate more efficient
+// code. For all practical purposes this is fine because the configuration
+// is the same for all known NVPTX architectures.
+enum MachineConfiguration : unsigned {
+ WarpSize = 32,
+ // Number of bits required to represent a lane identifier, which is
+ // computed as log_2(WarpSize).
+ LaneIDBits = 5,
+ LaneIDMask = WarpSize - 1,
+};
+
+enum NamedBarrier : unsigned {
+ // Synchronize on this barrier #ID using a named barrier primitive.
+ // Only the subset of active threads in a parallel region arrive at the
+ // barrier.
+ NB_Parallel = 1,
+};
} // anonymous namespace
/// Get the GPU warp size.
@@ -120,6 +153,23 @@
llvm::None, "nvptx_tid");
}
+/// Get the id of the warp in the block.
+/// We assume that the warp size is 32, which is always the case
+/// on the NVPTX device, to generate more efficient code.
+static llvm::Value *getNVPTXWarpID(CodeGenFunction &CGF) {
+ CGBuilderTy &Bld = CGF.Builder;
+ return Bld.CreateAShr(getNVPTXThreadID(CGF), LaneIDBits, "nvptx_warp_id");
+}
+
+/// Get the id of the current lane in the Warp.
+/// We assume that the warp size is 32, which is always the case
+/// on the NVPTX device, to generate more efficient code.
+static llvm::Value *getNVPTXLaneID(CodeGenFunction &CGF) {
+ CGBuilderTy &Bld = CGF.Builder;
+ return Bld.CreateAnd(getNVPTXThreadID(CGF), Bld.getInt32(LaneIDMask),
+ "nvptx_lane_id");
+}
+
/// Get the maximum number of threads in a block of the GPU.
static llvm::Value *getNVPTXNumThreads(CodeGenFunction &CGF) {
CGBuilderTy &Bld = CGF.Builder;
@@ -136,9 +186,25 @@
&CGF.CGM.getModule(), llvm::Intrinsic::nvvm_barrier0));
}
+/// Get barrier #ID to synchronize selected (multiple of warp size) threads in
+/// a CTA.
+static void getNVPTXBarrier(CodeGenFunction &CGF, int ID,
+ llvm::Value *NumThreads) {
+ CGBuilderTy &Bld = CGF.Builder;
+ llvm::Value *Args[] = {Bld.getInt32(ID), NumThreads};
+ Bld.CreateCall(llvm::Intrinsic::getDeclaration(&CGF.CGM.getModule(),
+ llvm::Intrinsic::nvvm_barrier),
+ Args);
+}
+
/// Synchronize all GPU threads in a block.
static void syncCTAThreads(CodeGenFunction &CGF) { getNVPTXCTABarrier(CGF); }
+/// Synchronize worker threads in a parallel region.
+static void syncParallelThreads(CodeGenFunction &CGF, llvm::Value *NumThreads) {
+ return getNVPTXBarrier(CGF, NB_Parallel, NumThreads);
+}
+
/// Get the value of the thread_limit clause in the teams directive.
/// For the 'generic' execution mode, the runtime encodes thread_limit in
/// the launch parameters, always starting thread_limit+warpSize threads per
@@ -583,6 +649,60 @@
RTLFn = CGM.CreateRuntimeFunction(FnTy, "__kmpc_end_serialized_parallel");
break;
}
+ case OMPRTL_NVPTX__kmpc_shuffle_int32: {
+ /// Build int32_t __kmpc_shuffle_int32(int32_t element,
+ /// int16_t lane_offset, int16_t warp_size);
+ llvm::Type *TypeParams[] = {CGM.Int32Ty, CGM.Int16Ty, CGM.Int16Ty};
+ llvm::FunctionType *FnTy =
+ llvm::FunctionType::get(CGM.Int32Ty, TypeParams, /*isVarArg*/ false);
+ RTLFn = CGM.CreateRuntimeFunction(FnTy, "__kmpc_shuffle_int32");
+ break;
+ }
+ case OMPRTL_NVPTX__kmpc_shuffle_int64: {
+ /// Build int64_t __kmpc_shuffle_int64(int64_t element,
+ /// int16_t lane_offset, int16_t warp_size);
+ llvm::Type *TypeParams[] = {CGM.Int64Ty, CGM.Int16Ty, CGM.Int16Ty};
+ llvm::FunctionType *FnTy =
+ llvm::FunctionType::get(CGM.Int64Ty, TypeParams, /*isVarArg*/ false);
+ RTLFn = CGM.CreateRuntimeFunction(FnTy, "__kmpc_shuffle_int64");
+ break;
+ }
+ case OMPRTL_NVPTX__kmpc_parallel_reduce_nowait: {
+ /// Build int32_t kmpc_nvptx_parallel_reduce_nowait(kmp_int32 global_tid,
+ /// kmp_int32 num_vars, size_t reduce_size, void* reduce_data,
+ /// void (*kmp_ShuffleReductFctPtr)(void *rhsData, int16_t lane_id, int16_t
+ /// lane_offset, int16_t Algorithm Version),
+ /// void (*kmp_InterWarpCopyFctPtr)(void* src, int warp_num));
+ llvm::Type *ShuffleReduceTypeParams[] = {CGM.VoidPtrTy, CGM.Int16Ty,
+ CGM.Int16Ty, CGM.Int16Ty};
+ auto *ShuffleReduceFnTy =
+ llvm::FunctionType::get(CGM.VoidTy, ShuffleReduceTypeParams,
+ /*isVarArg=*/false);
+ llvm::Type *InterWarpCopyTypeParams[] = {CGM.VoidPtrTy, CGM.Int32Ty};
+ auto *InterWarpCopyFnTy =
+ llvm::FunctionType::get(CGM.VoidTy, InterWarpCopyTypeParams,
+ /*isVarArg=*/false);
+ llvm::Type *TypeParams[] = {CGM.Int32Ty,
+ CGM.Int32Ty,
+ CGM.SizeTy,
+ CGM.VoidPtrTy,
+ ShuffleReduceFnTy->getPointerTo(),
+ InterWarpCopyFnTy->getPointerTo()};
+ llvm::FunctionType *FnTy =
+ llvm::FunctionType::get(CGM.Int32Ty, TypeParams, /*isVarArg=*/false);
+ RTLFn = CGM.CreateRuntimeFunction(
+ FnTy, /*Name=*/"__kmpc_nvptx_parallel_reduce_nowait");
+ break;
+ }
+ case OMPRTL_NVPTX__kmpc_end_reduce_nowait: {
+ // Build __kmpc_end_reduce_nowait(kmp_int32 global_tid);
+ llvm::Type *TypeParams[] = {CGM.Int32Ty};
+ llvm::FunctionType *FnTy =
+ llvm::FunctionType::get(CGM.VoidTy, TypeParams, /*isVarArg=*/false);
+ RTLFn = CGM.CreateRuntimeFunction(
+ FnTy, /*Name=*/"__kmpc_nvptx_end_reduce_nowait");
+ break;
+ }
}
return RTLFn;
}
@@ -805,3 +925,892 @@
OutlinedFnArgs.append(CapturedVars.begin(), CapturedVars.end());
CGF.EmitCallOrInvoke(OutlinedFn, OutlinedFnArgs);
}
+
+/// This function creates calls to one of two shuffle functions to copy
+/// variables between lanes in a warp.
+static llvm::Value *createRuntimeShuffleFunction(CodeGenFunction &CGF,
+ QualType ElemTy,
+ llvm::Value *Elem,
+ llvm::Value *Offset) {
+ auto &CGM = CGF.CGM;
+ auto &C = CGM.getContext();
+ auto &Bld = CGF.Builder;
+ CGOpenMPRuntimeNVPTX &RT =
+ *(static_cast<CGOpenMPRuntimeNVPTX *>(&CGM.getOpenMPRuntime()));
+
+ unsigned Size = CGM.getContext().getTypeSizeInChars(ElemTy).getQuantity();
+ assert(Size <= 8 && "Unsupported bitwidth in shuffle instruction.");
+
+ OpenMPRTLFunctionNVPTX ShuffleFn = Size <= 4
+ ? OMPRTL_NVPTX__kmpc_shuffle_int32
+ : OMPRTL_NVPTX__kmpc_shuffle_int64;
+
+ // Cast all types to 32- or 64-bit values before calling shuffle routines.
+ auto CastTy = Size <= 4 ? CGM.Int32Ty : CGM.Int64Ty;
+ auto *ElemCast = Bld.CreateSExtOrBitCast(Elem, CastTy);
+ auto *WarpSize = CGF.EmitScalarConversion(
+ getNVPTXWarpSize(CGF), C.getIntTypeForBitwidth(32, /* Signed */ true),
+ C.getIntTypeForBitwidth(16, /* Signed */ true), SourceLocation());
+
+ auto *ShuffledVal =
+ CGF.EmitRuntimeCall(RT.createNVPTXRuntimeFunction(ShuffleFn),
+ {ElemCast, Offset, WarpSize});
+
+ return Bld.CreateTruncOrBitCast(ShuffledVal, CGF.ConvertTypeForMem(ElemTy));
+}
+
+namespace {
+enum CopyAction : unsigned {
+ RemoteLaneToThread,
+ ThreadCopy,
+};
+} // namespace
+
+// Emit instructions to copy a Reduce list, which contains partially
+// aggregated values, in the specified direction.
+//
+// RemoteLaneToThread: Copy over a Reduce list from a remote lane in
+// the warp using shuffle instructions.
+// ThreadCopy: Make a copy of a Reduce list on the thread's stack.
+static void emitReductionListCopy(CopyAction Action, CodeGenFunction &CGF,
+ QualType ReductionArrayTy,
+ ArrayRef<const Expr *> Privates,
+ Address SrcBase, Address DestBase,
+ llvm::Value *RemoteLaneOffset = nullptr) {
+
+ auto &CGM = CGF.CGM;
+ auto &C = CGM.getContext();
+ auto &Bld = CGF.Builder;
+
+ // Iterates, element-by-element, through the source Reduce list and
+ // make a copy.
+ unsigned Idx = 0;
+ for (auto &Private : Privates) {
+ Address SrcElementAddr = Address::invalid();
+ Address DestElementAddr = Address::invalid();
+ Address DestElementPtrAddr = Address::invalid();
+ // Should we shuffle in an element from a remote lane?
+ bool ShuffleInElement = false;
+ // Set to true to update the pointer in the dest Reduce list to a
+ // newly created element.
+ bool UpdateDestListPtr = false;
+
+ switch (Action) {
+ case RemoteLaneToThread: {
+ // Step 1.1: Get the address for the src element in the Reduce list.
+ Address SrcElementPtrAddr =
+ Bld.CreateConstArrayGEP(SrcBase, Idx, CGF.getPointerSize());
+ llvm::Value *SrcElementPtrPtr = CGF.EmitLoadOfScalar(
+ SrcElementPtrAddr, /*Volatile=*/false, C.VoidPtrTy, SourceLocation());
+ SrcElementAddr =
+ Address(SrcElementPtrPtr, C.getTypeAlignInChars(Private->getType()));
+
+ // Step 1.2: Create a temporary to store the element in the destination
+ // Reduce list.
+ DestElementPtrAddr =
+ Bld.CreateConstArrayGEP(DestBase, Idx, CGF.getPointerSize());
+ DestElementAddr =
+ CGF.CreateMemTemp(Private->getType(), ".omp.reduction.element");
+ ShuffleInElement = true;
+ UpdateDestListPtr = true;
+ break;
+ }
+ case ThreadCopy: {
+ // Step 1.1: Get the address for the src element in the Reduce list.
+ Address SrcElementPtrAddr =
+ Bld.CreateConstArrayGEP(SrcBase, Idx, CGF.getPointerSize());
+ llvm::Value *SrcElementPtrPtr = CGF.EmitLoadOfScalar(
+ SrcElementPtrAddr, /*Volatile=*/false, C.VoidPtrTy, SourceLocation());
+ SrcElementAddr =
+ Address(SrcElementPtrPtr, C.getTypeAlignInChars(Private->getType()));
+
+ // Step 1.2: Get the address for dest element. The destination
+ // element has already been created on the thread's stack.
+ DestElementPtrAddr =
+ Bld.CreateConstArrayGEP(DestBase, Idx, CGF.getPointerSize());
+ llvm::Value *DestElementPtr =
+ CGF.EmitLoadOfScalar(DestElementPtrAddr, /*Volatile=*/false,
+ C.VoidPtrTy, SourceLocation());
+ Address DestElemAddr =
+ Address(DestElementPtr, C.getTypeAlignInChars(Private->getType()));
+ DestElementAddr = Bld.CreateElementBitCast(
+ DestElemAddr, CGF.ConvertTypeForMem(Private->getType()));
+ break;
+ }
+ }
+
+ // Regardless of src and dest of copy, we emit the load of src
+ // element as this is required in all directions
+ SrcElementAddr = Bld.CreateElementBitCast(
+ SrcElementAddr, CGF.ConvertTypeForMem(Private->getType()));
+ llvm::Value *Elem =
+ CGF.EmitLoadOfScalar(SrcElementAddr, /*Volatile=*/false,
+ Private->getType(), SourceLocation());
+
+ // Now that all active lanes have read the element in the
+ // Reduce list, shuffle over the value from the remote lane.
+ if (ShuffleInElement) {
+ Elem = createRuntimeShuffleFunction(CGF, Private->getType(), Elem,
+ RemoteLaneOffset);
+ }
+
+ // Store the source element value to the dest element address.
+ CGF.EmitStoreOfScalar(Elem, DestElementAddr, /*Volatile=*/false,
+ Private->getType());
+
+ // Step 3.1: Modify reference in dest Reduce list as needed.
+ // Modifying the reference in Reduce list to point to the newly
+ // created element. The element is live in the current function
+ // scope and that of functions it invokes (i.e., reduce_function).
+ // RemoteReduceData[i] = (void*)&RemoteElem
+ if (UpdateDestListPtr) {
+ CGF.EmitStoreOfScalar(Bld.CreatePointerBitCastOrAddrSpaceCast(
+ DestElementAddr.getPointer(), CGF.VoidPtrTy),
+ DestElementPtrAddr, /*Volatile=*/false,
+ C.VoidPtrTy);
+ }
+
+ Idx++;
+ }
+}
+
+// This function emits a helper that gathers Reduce lists from the first
+// lane of every active warp to lanes in the first warp.
+//
+// void inter_warp_copy_func(void* reduce_data, num_warps)
+// shared smem[warp_size];
+// For all data entries D in reduce_data:
+// If (I am the first lane in each warp)
+// Copy my local D to smem[warp_id]
+// sync
+// if (I am the first warp)
+// Copy smem[thread_id] to my local D
+// sync
+static llvm::Value *emitInterWarpCopyFunction(CodeGenModule &CGM,
+ ArrayRef<const Expr *> Privates,
+ QualType ReductionArrayTy) {
+ auto &C = CGM.getContext();
+ auto &M = CGM.getModule();
+
+ // ReduceList: thread local Reduce list.
+ // At the stage of the computation when this function is called, partially
+ // aggregated values reside in the first lane of every active warp.
+ ImplicitParamDecl ReduceListArg(C, /*DC=*/nullptr, SourceLocation(),
+ /*Id=*/nullptr, C.VoidPtrTy);
+ // NumWarps: number of warps active in the parallel region. This could
+ // be smaller than 32 (max warps in a CTA) for partial block reduction.
+ ImplicitParamDecl NumWarpsArg(C, /*DC=*/nullptr, SourceLocation(),
+ /*Id=*/nullptr, C.IntTy);
+ FunctionArgList Args;
+ Args.push_back(&ReduceListArg);
+ Args.push_back(&NumWarpsArg);
+
+ auto &CGFI = CGM.getTypes().arrangeBuiltinFunctionDeclaration(C.VoidTy, Args);
+ auto *Fn = llvm::Function::Create(
+ CGM.getTypes().GetFunctionType(CGFI), llvm::GlobalValue::InternalLinkage,
+ "_omp_reduction_inter_warp_copy_func", &CGM.getModule());
+ CGM.SetInternalFunctionAttributes(/*DC=*/nullptr, Fn, CGFI);
+ CodeGenFunction CGF(CGM);
+ // We don't need debug information in this function as nothing here refers to
+ // user code.
+ CGF.disableDebugInfo();
+ CGF.StartFunction(GlobalDecl(), C.VoidTy, Fn, CGFI, Args);
+
+ auto &Bld = CGF.Builder;
+
+ // This array is used as a medium to transfer, one reduce element at a time,
+ // the data from the first lane of every warp to lanes in the first warp
+ // in order to perform the final step of a reduction in a parallel region
+ // (reduction across warps). The array is placed in NVPTX __shared__ memory
+ // for reduced latency, as well as to have a distinct copy for concurrently
+ // executing target regions. The array is declared with common linkage so
+ // as to be shared across compilation units.
+ const char *TransferMediumName =
+ "__openmp_nvptx_data_transfer_temporary_storage";
+ llvm::GlobalVariable *TransferMedium =
+ M.getGlobalVariable(TransferMediumName);
+ if (!TransferMedium) {
+ auto *Ty = llvm::ArrayType::get(CGM.Int64Ty, WarpSize);
+ unsigned SharedAddressSpace = C.getTargetAddressSpace(LangAS::cuda_shared);
+ TransferMedium = new llvm::GlobalVariable(
+ M, Ty,
+ /*isConstant=*/false, llvm::GlobalVariable::CommonLinkage,
+ llvm::Constant::getNullValue(Ty), TransferMediumName,
+ /*InsertBefore=*/nullptr, llvm::GlobalVariable::NotThreadLocal,
+ SharedAddressSpace);
+ }
+
+ // Get the CUDA thread id of the current OpenMP thread on the GPU.
+ auto *ThreadID = getNVPTXThreadID(CGF);
+ // nvptx_lane_id = nvptx_id % warpsize
+ auto *LaneID = getNVPTXLaneID(CGF);
+ // nvptx_warp_id = nvptx_id / warpsize
+ auto *WarpID = getNVPTXWarpID(CGF);
+
+ Address AddrReduceListArg = CGF.GetAddrOfLocalVar(&ReduceListArg);
+ Address LocalReduceList(
+ Bld.CreatePointerBitCastOrAddrSpaceCast(
+ CGF.EmitLoadOfScalar(AddrReduceListArg, /*Volatile=*/false,
+ C.VoidPtrTy, SourceLocation()),
+ CGF.ConvertTypeForMem(ReductionArrayTy)->getPointerTo()),
+ CGF.getPointerAlign());
+
+ unsigned Idx = 0;
+ for (auto &Private : Privates) {
+ //
+ // Warp master copies reduce element to transfer medium in __shared__
+ // memory.
+ //
+ llvm::BasicBlock *ThenBB = CGF.createBasicBlock("then");
+ llvm::BasicBlock *ElseBB = CGF.createBasicBlock("else");
+ llvm::BasicBlock *MergeBB = CGF.createBasicBlock("ifcont");
+
+ // if (lane_id == 0)
+ auto IsWarpMaster =
+ Bld.CreateICmpEQ(LaneID, Bld.getInt32(0), "warp_master");
+ Bld.CreateCondBr(IsWarpMaster, ThenBB, ElseBB);
+ CGF.EmitBlock(ThenBB);
+
+ // Reduce element = LocalReduceList[i]
+ Address ElemPtrPtrAddr =
+ Bld.CreateConstArrayGEP(LocalReduceList, Idx, CGF.getPointerSize());
+ llvm::Value *ElemPtrPtr = CGF.EmitLoadOfScalar(
+ ElemPtrPtrAddr, /*Volatile=*/false, C.VoidPtrTy, SourceLocation());
+ // elemptr = (type[i]*)(elemptrptr)
+ Address ElemPtr =
+ Address(ElemPtrPtr, C.getTypeAlignInChars(Private->getType()));
+ ElemPtr = Bld.CreateElementBitCast(
+ ElemPtr, CGF.ConvertTypeForMem(Private->getType()));
+ // elem = *elemptr
+ llvm::Value *Elem = CGF.EmitLoadOfScalar(
+ ElemPtr, /*Volatile=*/false, Private->getType(), SourceLocation());
+
+ // Get pointer to location in transfer medium.
+ // MediumPtr = &medium[warp_id]
+ llvm::Value *MediumPtrVal = Bld.CreateInBoundsGEP(
+ TransferMedium, {llvm::Constant::getNullValue(CGM.Int64Ty), WarpID});
+ Address MediumPtr(MediumPtrVal, C.getTypeAlignInChars(Private->getType()));
+ // Casting to actual data type.
+ // MediumPtr = (type[i]*)MediumPtrAddr;
+ MediumPtr = Bld.CreateElementBitCast(
+ MediumPtr, CGF.ConvertTypeForMem(Private->getType()));
+
+ //*MediumPtr = elem
+ Bld.CreateStore(Elem, MediumPtr);
+
+ Bld.CreateBr(MergeBB);
+
+ CGF.EmitBlock(ElseBB);
+ Bld.CreateBr(MergeBB);
+
+ CGF.EmitBlock(MergeBB);
+
+ Address AddrNumWarpsArg = CGF.GetAddrOfLocalVar(&NumWarpsArg);
+ llvm::Value *NumWarpsVal = CGF.EmitLoadOfScalar(
+ AddrNumWarpsArg, /*Volatile=*/false, C.IntTy, SourceLocation());
+
+ auto *NumActiveThreads = Bld.CreateNSWMul(
+ NumWarpsVal, getNVPTXWarpSize(CGF), "num_active_threads");
+ // named_barrier_sync(ParallelBarrierID, num_active_threads)
+ syncParallelThreads(CGF, NumActiveThreads);
+
+ //
+ // Warp 0 copies reduce element from transfer medium.
+ //
+ llvm::BasicBlock *W0ThenBB = CGF.createBasicBlock("then");
+ llvm::BasicBlock *W0ElseBB = CGF.createBasicBlock("else");
+ llvm::BasicBlock *W0MergeBB = CGF.createBasicBlock("ifcont");
+
+ // Up to 32 threads in warp 0 are active.
+ auto IsActiveThread =
+ Bld.CreateICmpULT(ThreadID, NumWarpsVal, "is_active_thread");
+ Bld.CreateCondBr(IsActiveThread, W0ThenBB, W0ElseBB);
+
+ CGF.EmitBlock(W0ThenBB);
+
+ // SrcMediumPtr = &medium[tid]
+ llvm::Value *SrcMediumPtrVal = Bld.CreateInBoundsGEP(
+ TransferMedium, {llvm::Constant::getNullValue(CGM.Int64Ty), ThreadID});
+ Address SrcMediumPtr(SrcMediumPtrVal,
+ C.getTypeAlignInChars(Private->getType()));
+ // SrcMediumVal = *SrcMediumPtr;
+ SrcMediumPtr = Bld.CreateElementBitCast(
+ SrcMediumPtr, CGF.ConvertTypeForMem(Private->getType()));
+ llvm::Value *SrcMediumValue = CGF.EmitLoadOfScalar(
+ SrcMediumPtr, /*Volatile=*/false, Private->getType(), SourceLocation());
+
+ // TargetElemPtr = (type[i]*)(SrcDataAddr[i])
+ Address TargetElemPtrPtr =
+ Bld.CreateConstArrayGEP(LocalReduceList, Idx, CGF.getPointerSize());
+ llvm::Value *TargetElemPtrVal = CGF.EmitLoadOfScalar(
+ TargetElemPtrPtr, /*Volatile=*/false, C.VoidPtrTy, SourceLocation());
+ Address TargetElemPtr =
+ Address(TargetElemPtrVal, C.getTypeAlignInChars(Private->getType()));
+ TargetElemPtr = Bld.CreateElementBitCast(
+ TargetElemPtr, CGF.ConvertTypeForMem(Private->getType()));
+
+ // *TargetElemPtr = SrcMediumVal;
+ CGF.EmitStoreOfScalar(SrcMediumValue, TargetElemPtr, /*Volatile=*/false,
+ Private->getType());
+ Bld.CreateBr(W0MergeBB);
+
+ CGF.EmitBlock(W0ElseBB);
+ Bld.CreateBr(W0MergeBB);
+
+ CGF.EmitBlock(W0MergeBB);
+
+ // While warp 0 copies values from transfer medium, all other warps must
+ // wait.
+ syncParallelThreads(CGF, NumActiveThreads);
+ Idx++;
+ }
+
+ CGF.FinishFunction();
+ return Fn;
+}
+
+// Emit a helper that reduces data across two OpenMP threads (lanes)
+// in the same warp. It uses shuffle instructions to copy over data from
+// a remote lane's stack. The reduction algorithm performed is specified
+// by the fourth parameter.
+//
+// Algorithm Versions.
+// Full Warp Reduce (argument value 0):
+// This algorithm assumes that all 32 lanes are active and gathers
+// data from these 32 lanes, producing a single resultant value.
+// Contiguous Partial Warp Reduce (argument value 1):
+// This algorithm assumes that only a *contiguous* subset of lanes
+// are active. This happens for the last warp in a parallel region
+// when the user specified num_threads is not an integer multiple of
+// 32. This contiguous subset always starts with the zeroth lane.
+// Partial Warp Reduce (argument value 2):
+// This algorithm gathers data from any number of lanes at any position.
+// All reduced values are stored in the lowest possible lane. The set
+// of problems every algorithm addresses is a super set of those
+// addressable by algorithms with a lower version number. Overhead
+// increases as algorithm version increases.
+//
+// Terminology
+// Reduce element:
+// Reduce element refers to the individual data field with primitive
+// data types to be combined and reduced across threads.
+// Reduce list:
+// Reduce list refers to a collection of local, thread-private
+// reduce elements.
+// Remote Reduce list:
+// Remote Reduce list refers to a collection of remote (relative to
+// the current thread) reduce elements.
+//
+// We distinguish between three states of threads that are important to
+// the implementation of this function.
+// Alive threads:
+// Threads in a warp executing the SIMT instruction, as distinguished from
+// threads that are inactive due to divergent control flow.
+// Active threads:
+// The minimal set of threads that has to be alive upon entry to this
+// function. The computation is correct iff active threads are alive.
+// Some threads are alive but they are not active because they do not
+// contribute to the computation in any useful manner. Turning them off
+// may introduce control flow overheads without any tangible benefits.
+// Effective threads:
+// In order to comply with the argument requirements of the shuffle
+// function, we must keep all lanes holding data alive. But at most
+// half of them perform value aggregation; we refer to this half of
+// threads as effective. The other half is simply handing off their
+// data.
+//
+// Procedure
+// Value shuffle:
+// In this step active threads transfer data from higher lane positions
+// in the warp to lower lane positions, creating Remote Reduce list.
+// Value aggregation:
+// In this step, effective threads combine their thread local Reduce list
+// with Remote Reduce list and store the result in the thread local
+// Reduce list.
+// Value copy:
+// In this step, we deal with the assumption made by algorithm 2
+// (i.e. contiguity assumption). When we have an odd number of lanes
+// active, say 2k+1, only k threads will be effective and therefore k
+// new values will be produced. However, the Reduce list owned by the
+// (2k+1)th thread is ignored in the value aggregation. Therefore
+// we copy the Reduce list from the (2k+1)th lane to (k+1)th lane so
+// that the contiguity assumption still holds.
+static llvm::Value *
+emitShuffleAndReduceFunction(CodeGenModule &CGM,
+ ArrayRef<const Expr *> Privates,
+ QualType ReductionArrayTy, llvm::Value *ReduceFn) {
+ auto &C = CGM.getContext();
+
+ // Thread local Reduce list used to host the values of data to be reduced.
+ ImplicitParamDecl ReduceListArg(C, /*DC=*/nullptr, SourceLocation(),
+ /*Id=*/nullptr, C.VoidPtrTy);
+ // Current lane id; could be logical.
+ ImplicitParamDecl LaneIDArg(C, /*DC=*/nullptr, SourceLocation(),
+ /*Id=*/nullptr, C.ShortTy);
+ // Offset of the remote source lane relative to the current lane.
+ ImplicitParamDecl RemoteLaneOffsetArg(C, /*DC=*/nullptr, SourceLocation(),
+ /*Id=*/nullptr, C.ShortTy);
+ // Algorithm version. This is expected to be known at compile time.
+ ImplicitParamDecl AlgoVerArg(C, /*DC=*/nullptr, SourceLocation(),
+ /*Id=*/nullptr, C.ShortTy);
+ FunctionArgList Args;
+ Args.push_back(&ReduceListArg);
+ Args.push_back(&LaneIDArg);
+ Args.push_back(&RemoteLaneOffsetArg);
+ Args.push_back(&AlgoVerArg);
+
+ auto &CGFI = CGM.getTypes().arrangeBuiltinFunctionDeclaration(C.VoidTy, Args);
+ auto *Fn = llvm::Function::Create(
+ CGM.getTypes().GetFunctionType(CGFI), llvm::GlobalValue::InternalLinkage,
+ "_omp_reduction_shuffle_and_reduce_func", &CGM.getModule());
+ CGM.SetInternalFunctionAttributes(/*D=*/nullptr, Fn, CGFI);
+ CodeGenFunction CGF(CGM);
+ // We don't need debug information in this function as nothing here refers to
+ // user code.
+ CGF.disableDebugInfo();
+ CGF.StartFunction(GlobalDecl(), C.VoidTy, Fn, CGFI, Args);
+
+ auto &Bld = CGF.Builder;
+
+ Address AddrReduceListArg = CGF.GetAddrOfLocalVar(&ReduceListArg);
+ Address LocalReduceList(
+ Bld.CreatePointerBitCastOrAddrSpaceCast(
+ CGF.EmitLoadOfScalar(AddrReduceListArg, /*Volatile=*/false,
+ C.VoidPtrTy, SourceLocation()),
+ CGF.ConvertTypeForMem(ReductionArrayTy)->getPointerTo()),
+ CGF.getPointerAlign());
+
+ Address AddrLaneIDArg = CGF.GetAddrOfLocalVar(&LaneIDArg);
+ llvm::Value *LaneIDArgVal = CGF.EmitLoadOfScalar(
+ AddrLaneIDArg, /*Volatile=*/false, C.ShortTy, SourceLocation());
+
+ Address AddrRemoteLaneOffsetArg = CGF.GetAddrOfLocalVar(&RemoteLaneOffsetArg);
+ llvm::Value *RemoteLaneOffsetArgVal = CGF.EmitLoadOfScalar(
+ AddrRemoteLaneOffsetArg, /*Volatile=*/false, C.ShortTy, SourceLocation());
+
+ Address AddrAlgoVerArg = CGF.GetAddrOfLocalVar(&AlgoVerArg);
+ llvm::Value *AlgoVerArgVal = CGF.EmitLoadOfScalar(
+ AddrAlgoVerArg, /*Volatile=*/false, C.ShortTy, SourceLocation());
+
+ // Create a local thread-private variable to host the Reduce list
+ // from a remote lane.
+ Address RemoteReduceList =
+ CGF.CreateMemTemp(ReductionArrayTy, ".omp.reduction.remote_reduce_list");
+
+ // This loop iterates through the list of reduce elements and copies,
+ // element by element, from a remote lane in the warp to RemoteReduceList,
+ // hosted on the thread's stack.
+ emitReductionListCopy(RemoteLaneToThread, CGF, ReductionArrayTy, Privates,
+ LocalReduceList, RemoteReduceList,
+ RemoteLaneOffsetArgVal);
+
+ // The actions to be performed on the Remote Reduce list is dependent
+ // on the algorithm version.
+ //
+ // if (AlgoVer==0) || (AlgoVer==1 && (LaneId < Offset)) || (AlgoVer==2 &&
+ // LaneId % 2 == 0 && Offset > 0):
+ // do the reduction value aggregation
+ //
+ // The thread local variable Reduce list is mutated in place to host the
+ // reduced data, which is the aggregated value produced from local and
+ // remote lanes.
+ //
+ // Note that AlgoVer is expected to be a constant integer known at compile
+ // time.
+ // When AlgoVer==0, the first conjunction evaluates to true, making
+ // the entire predicate true during compile time.
+ // When AlgoVer==1, the second conjunction has only the second part to be
+ // evaluated during runtime. Other conjunctions evaluates to false
+ // during compile time.
+ // When AlgoVer==2, the third conjunction has only the second part to be
+ // evaluated during runtime. Other conjunctions evaluates to false
+ // during compile time.
+ auto CondAlgo0 = Bld.CreateICmpEQ(AlgoVerArgVal, Bld.getInt16(0));
+
+ auto CondAlgo1 =
+ Bld.CreateAnd(Bld.CreateICmpEQ(AlgoVerArgVal, Bld.getInt16(1)),
+ Bld.CreateICmpULT(LaneIDArgVal, RemoteLaneOffsetArgVal));
+
+ auto CondAlgo2 = Bld.CreateAnd(
+ Bld.CreateICmpEQ(AlgoVerArgVal, Bld.getInt16(2)),
+ Bld.CreateICmpEQ(Bld.CreateAnd(LaneIDArgVal, Bld.getInt16(1)),
+ Bld.getInt16(0)));
+ CondAlgo2 = Bld.CreateAnd(
+ CondAlgo2, Bld.CreateICmpSGT(RemoteLaneOffsetArgVal, Bld.getInt16(0)));
+
+ auto CondReduce = Bld.CreateOr(CondAlgo0, CondAlgo1);
+ CondReduce = Bld.CreateOr(CondReduce, CondAlgo2);
+
+ llvm::BasicBlock *ThenBB = CGF.createBasicBlock("then");
+ llvm::BasicBlock *ElseBB = CGF.createBasicBlock("else");
+ llvm::BasicBlock *MergeBB = CGF.createBasicBlock("ifcont");
+ Bld.CreateCondBr(CondReduce, ThenBB, ElseBB);
+
+ CGF.EmitBlock(ThenBB);
+ // reduce_function(LocalReduceList, RemoteReduceList)
+ llvm::Value *LocalReduceListPtr = Bld.CreatePointerBitCastOrAddrSpaceCast(
+ LocalReduceList.getPointer(), CGF.VoidPtrTy);
+ llvm::Value *RemoteReduceListPtr = Bld.CreatePointerBitCastOrAddrSpaceCast(
+ RemoteReduceList.getPointer(), CGF.VoidPtrTy);
+ CGF.EmitCallOrInvoke(ReduceFn, {LocalReduceListPtr, RemoteReduceListPtr});
+ Bld.CreateBr(MergeBB);
+
+ CGF.EmitBlock(ElseBB);
+ Bld.CreateBr(MergeBB);
+
+ CGF.EmitBlock(MergeBB);
+
+ // if (AlgoVer==1 && (LaneId >= Offset)) copy Remote Reduce list to local
+ // Reduce list.
+ auto CondCopy =
+ Bld.CreateAnd(Bld.CreateICmpEQ(AlgoVerArgVal, Bld.getInt16(1)),
+ Bld.CreateICmpUGE(LaneIDArgVal, RemoteLaneOffsetArgVal));
+
+ llvm::BasicBlock *CpyThenBB = CGF.createBasicBlock("then");
+ llvm::BasicBlock *CpyElseBB = CGF.createBasicBlock("else");
+ llvm::BasicBlock *CpyMergeBB = CGF.createBasicBlock("ifcont");
+ Bld.CreateCondBr(CondCopy, CpyThenBB, CpyElseBB);
+
+ CGF.EmitBlock(CpyThenBB);
+ emitReductionListCopy(ThreadCopy, CGF, ReductionArrayTy, Privates,
+ RemoteReduceList, LocalReduceList);
+ Bld.CreateBr(CpyMergeBB);
+
+ CGF.EmitBlock(CpyElseBB);
+ Bld.CreateBr(CpyMergeBB);
+
+ CGF.EmitBlock(CpyMergeBB);
+
+ CGF.FinishFunction();
+ return Fn;
+}
+
+//
+// Design of OpenMP reductions on the GPU
+//
+// Consider a typical OpenMP program with one or more reduction
+// clauses:
+//
+// float foo;
+// double bar;
+// #pragma omp target teams distribute parallel for \
+// reduction(+:foo) reduction(*:bar)
+// for (int i = 0; i < N; i++) {
+// foo += A[i]; bar *= B[i];
+// }
+//
+// where 'foo' and 'bar' are reduced across all OpenMP threads in
+// all teams. In our OpenMP implementation on the NVPTX device an
+// OpenMP team is mapped to a CUDA threadblock and OpenMP threads
+// within a team are mapped to CUDA threads within a threadblock.
+// Our goal is to efficiently aggregate values across all OpenMP
+// threads such that:
+//
+// - the compiler and runtime are logically concise, and
+// - the reduction is performed efficiently in a hierarchical
+// manner as follows: within OpenMP threads in the same warp,
+// across warps in a threadblock, and finally across teams on
+// the NVPTX device.
+//
+// Introduction to Decoupling
+//
+// We would like to decouple the compiler and the runtime so that the
+// latter is ignorant of the reduction variables (number, data types)
+// and the reduction operators. This allows a simpler interface
+// and implementation while still attaining good performance.
+//
+// Pseudocode for the aforementioned OpenMP program generated by the
+// compiler is as follows:
+//
+// 1. Create private copies of reduction variables on each OpenMP
+// thread: 'foo_private', 'bar_private'
+// 2. Each OpenMP thread reduces the chunk of 'A' and 'B' assigned
+// to it and writes the result in 'foo_private' and 'bar_private'
+// respectively.
+// 3. Call the OpenMP runtime on the GPU to reduce within a team
+// and store the result on the team master:
+//
+// __kmpc_nvptx_parallel_reduce_nowait(...,
+// reduceData, shuffleReduceFn, interWarpCpyFn)
+//
+// where:
+// struct ReduceData {
+// double *foo;
+// double *bar;
+// } reduceData
+// reduceData.foo = &foo_private
+// reduceData.bar = &bar_private
+//
+// 'shuffleReduceFn' and 'interWarpCpyFn' are pointers to two
+// auxiliary functions generated by the compiler that operate on
+// variables of type 'ReduceData'. They aid the runtime perform
+// algorithmic steps in a data agnostic manner.
+//
+// 'shuffleReduceFn' is a pointer to a function that reduces data
+// of type 'ReduceData' across two OpenMP threads (lanes) in the
+// same warp. It takes the following arguments as input:
+//
+// a. variable of type 'ReduceData' on the calling lane,
+// b. its lane_id,
+// c. an offset relative to the current lane_id to generate a
+// remote_lane_id. The remote lane contains the second
+// variable of type 'ReduceData' that is to be reduced.
+// d. an algorithm version parameter determining which reduction
+// algorithm to use.
+//
+// 'shuffleReduceFn' retrieves data from the remote lane using
+// efficient GPU shuffle intrinsics and reduces, using the
+// algorithm specified by the 4th parameter, the two operands
+// element-wise. The result is written to the first operand.
+//
+// Different reduction algorithms are implemented in different
+// runtime functions, all calling 'shuffleReduceFn' to perform
+// the essential reduction step. Therefore, based on the 4th
+// parameter, this function behaves slightly differently to
+// cooperate with the runtime to ensure correctness under
+// different circumstances.
+//
+// 'InterWarpCpyFn' is a pointer to a function that transfers
+// reduced variables across warps. It tunnels, through CUDA
+// shared memory, the thread-private data of type 'ReduceData'
+// from lane 0 of each warp to a lane in the first warp.
+// 5. if ret == 1:
+// The team master of the last team stores the reduced
+// result to the globals in memory.
+// foo += reduceData.foo; bar *= reduceData.bar
+//
+//
+// Warp Reduction Algorithms
+//
+// On the warp level, we have three algorithms implemented in the
+// OpenMP runtime depending on the number of active lanes:
+//
+// Full Warp Reduction
+//
+// The reduce algorithm within a warp where all lanes are active
+// is implemented in the runtime as follows:
+//
+// full_warp_reduce(void *reduce_data,
+// kmp_ShuffleReductFctPtr ShuffleReduceFn) {
+// for (int offset = WARPSIZE/2; offset > 0; offset /= 2)
+// ShuffleReduceFn(reduce_data, 0, offset, 0);
+// }
+//
+// The algorithm completes in log(2, WARPSIZE) steps.
+//
+// 'ShuffleReduceFn' is used here with lane_id set to 0 because it is
+// not used therefore we save instructions by not retrieving lane_id
+// from the corresponding special registers. The 4th parameter, which
+// represents the version of the algorithm being used, is set to 0 to
+// signify full warp reduction.
+//
+// In this version, 'ShuffleReduceFn' behaves, per element, as follows:
+//
+// #reduce_elem refers to an element in the local lane's data structure
+// #remote_elem is retrieved from a remote lane
+// remote_elem = shuffle_down(reduce_elem, offset, WARPSIZE);
+// reduce_elem = reduce_elem REDUCE_OP remote_elem;
+//
+// Contiguous Partial Warp Reduction
+//
+// This reduce algorithm is used within a warp where only the first
+// 'n' (n <= WARPSIZE) lanes are active. It is typically used when the
+// number of OpenMP threads in a parallel region is not a multiple of
+// WARPSIZE. The algorithm is implemented in the runtime as follows:
+//
+// void
+// contiguous_partial_reduce(void *reduce_data,
+// kmp_ShuffleReductFctPtr ShuffleReduceFn,
+// int size, int lane_id) {
+// int curr_size;
+// int offset;
+// curr_size = size;
+// mask = curr_size/2;
+// while (offset>0) {
+// ShuffleReduceFn(reduce_data, lane_id, offset, 1);
+// curr_size = (curr_size+1)/2;
+// offset = curr_size/2;
+// }
+// }
+//
+// In this version, 'ShuffleReduceFn' behaves, per element, as follows:
+//
+// remote_elem = shuffle_down(reduce_elem, offset, WARPSIZE);
+// if (lane_id < offset)
+// reduce_elem = reduce_elem REDUCE_OP remote_elem
+// else
+// reduce_elem = remote_elem
+//
+// This algorithm assumes that the data to be reduced are located in a
+// contiguous subset of lanes starting from the first. When there is
+// an odd number of active lanes, the data in the last lane is not
+// aggregated with any other lane's dat but is instead copied over.
+//
+// Dispersed Partial Warp Reduction
+//
+// This algorithm is used within a warp when any discontiguous subset of
+// lanes are active. It is used to implement the reduction operation
+// across lanes in an OpenMP simd region or in a nested parallel region.
+//
+// void
+// dispersed_partial_reduce(void *reduce_data,
+// kmp_ShuffleReductFctPtr ShuffleReduceFn) {
+// int size, remote_id;
+// int logical_lane_id = number_of_active_lanes_before_me() * 2;
+// do {
+// remote_id = next_active_lane_id_right_after_me();
+// # the above function returns 0 of no active lane
+// # is present right after the current lane.
+// size = number_of_active_lanes_in_this_warp();
+// logical_lane_id /= 2;
+// ShuffleReduceFn(reduce_data, logical_lane_id,
+// remote_id-1-threadIdx.x, 2);
+// } while (logical_lane_id % 2 == 0 && size > 1);
+// }
+//
+// There is no assumption made about the initial state of the reduction.
+// Any number of lanes (>=1) could be active at any position. The reduction
+// result is returned in the first active lane.
+//
+// In this version, 'ShuffleReduceFn' behaves, per element, as follows:
+//
+// remote_elem = shuffle_down(reduce_elem, offset, WARPSIZE);
+// if (lane_id % 2 == 0 && offset > 0)
+// reduce_elem = reduce_elem REDUCE_OP remote_elem
+// else
+// reduce_elem = remote_elem
+//
+//
+// Intra-Team Reduction
+//
+// This function, as implemented in the runtime call
+// '__kmpc_nvptx_parallel_reduce_nowait', aggregates data across OpenMP
+// threads in a team. It first reduces within a warp using the
+// aforementioned algorithms. We then proceed to gather all such
+// reduced values at the first warp.
+//
+// The runtime makes use of the function 'InterWarpCpyFn', which copies
+// data from each of the "warp master" (zeroth lane of each warp, where
+// warp-reduced data is held) to the zeroth warp. This step reduces (in
+// a mathematical sense) the problem of reduction across warp masters in
+// a block to the problem of warp reduction.
+//
+void CGOpenMPRuntimeNVPTX::emitReduction(
+ CodeGenFunction &CGF, SourceLocation Loc, ArrayRef<const Expr *> Privates,
+ ArrayRef<const Expr *> LHSExprs, ArrayRef<const Expr *> RHSExprs,
+ ArrayRef<const Expr *> ReductionOps, bool WithNowait, bool SimpleReduction,
+ OpenMPDirectiveKind ReductionKind) {
+ if (!CGF.HaveInsertPoint())
+ return;
+
+ bool ParallelReduction = isOpenMPParallelDirective(ReductionKind);
+ assert(ParallelReduction && "Invalid reduction selection in emitReduction.");
+
+ auto &C = CGM.getContext();
+
+ // 1. Build a list of reduction variables.
+ // void *RedList[<n>] = {<ReductionVars>[0], ..., <ReductionVars>[<n>-1]};
+ auto Size = RHSExprs.size();
+ for (auto *E : Privates) {
+ if (E->getType()->isVariablyModifiedType())
+ // Reserve place for array size.
+ ++Size;
+ }
+ llvm::APInt ArraySize(/*unsigned int numBits=*/32, Size);
+ QualType ReductionArrayTy =
+ C.getConstantArrayType(C.VoidPtrTy, ArraySize, ArrayType::Normal,
+ /*IndexTypeQuals=*/0);
+ Address ReductionList =
+ CGF.CreateMemTemp(ReductionArrayTy, ".omp.reduction.red_list");
+ auto IPriv = Privates.begin();
+ unsigned Idx = 0;
+ for (unsigned I = 0, E = RHSExprs.size(); I < E; ++I, ++IPriv, ++Idx) {
+ Address Elem = CGF.Builder.CreateConstArrayGEP(ReductionList, Idx,
+ CGF.getPointerSize());
+ CGF.Builder.CreateStore(
+ CGF.Builder.CreatePointerBitCastOrAddrSpaceCast(
+ CGF.EmitLValue(RHSExprs[I]).getPointer(), CGF.VoidPtrTy),
+ Elem);
+ if ((*IPriv)->getType()->isVariablyModifiedType()) {
+ // Store array size.
+ ++Idx;
+ Elem = CGF.Builder.CreateConstArrayGEP(ReductionList, Idx,
+ CGF.getPointerSize());
+ llvm::Value *Size = CGF.Builder.CreateIntCast(
+ CGF.getVLASize(
+ CGF.getContext().getAsVariableArrayType((*IPriv)->getType()))
+ .first,
+ CGF.SizeTy, /*isSigned=*/false);
+ CGF.Builder.CreateStore(CGF.Builder.CreateIntToPtr(Size, CGF.VoidPtrTy),
+ Elem);
+ }
+ }
+
+ // 2. Emit reduce_func().
+ auto *ReductionFn = emitReductionFunction(
+ CGM, CGF.ConvertTypeForMem(ReductionArrayTy)->getPointerTo(), Privates,
+ LHSExprs, RHSExprs, ReductionOps);
+
+ // 4. Build res = __kmpc_reduce{_nowait}(<gtid>, <n>, sizeof(RedList),
+ // RedList, shuffle_reduce_func, interwarp_copy_func);
+ auto *ThreadId = getThreadID(CGF, Loc);
+ auto *ReductionArrayTySize = CGF.getTypeSize(ReductionArrayTy);
+ auto *RL = CGF.Builder.CreatePointerBitCastOrAddrSpaceCast(
+ ReductionList.getPointer(), CGF.VoidPtrTy);
+
+ auto *ShuffleAndReduceFn = emitShuffleAndReduceFunction(
+ CGM, Privates, ReductionArrayTy, ReductionFn);
+ auto *InterWarpCopyFn =
+ emitInterWarpCopyFunction(CGM, Privates, ReductionArrayTy);
+
+ llvm::Value *Res = nullptr;
+ if (ParallelReduction) {
+ llvm::Value *Args[] = {ThreadId,
+ CGF.Builder.getInt32(RHSExprs.size()),
+ ReductionArrayTySize,
+ RL,
+ ShuffleAndReduceFn,
+ InterWarpCopyFn};
+
+ Res = CGF.EmitRuntimeCall(
+ createNVPTXRuntimeFunction(OMPRTL_NVPTX__kmpc_parallel_reduce_nowait),
+ Args);
+ }
+
+ // 5. Build switch(res)
+ auto *DefaultBB = CGF.createBasicBlock(".omp.reduction.default");
+ auto *SwInst = CGF.Builder.CreateSwitch(Res, DefaultBB, /*NumCases=*/1);
+
+ // 6. Build case 1: where we have reduced values in the master
+ // thread in each team.
+ // __kmpc_end_reduce{_nowait}(<gtid>);
+ // break;
+ auto *Case1BB = CGF.createBasicBlock(".omp.reduction.case1");
+ SwInst->addCase(CGF.Builder.getInt32(1), Case1BB);
+ CGF.EmitBlock(Case1BB);
+
+ // Add emission of __kmpc_end_reduce{_nowait}(<gtid>);
+ llvm::Value *EndArgs[] = {ThreadId};
+ auto &&CodeGen = [&Privates, &LHSExprs, &RHSExprs, &ReductionOps,
+ this](CodeGenFunction &CGF, PrePostActionTy &Action) {
+ auto IPriv = Privates.begin();
+ auto ILHS = LHSExprs.begin();
+ auto IRHS = RHSExprs.begin();
+ for (auto *E : ReductionOps) {
+ emitSingleReductionCombiner(CGF, E, *IPriv, cast<DeclRefExpr>(*ILHS),
+ cast<DeclRefExpr>(*IRHS));
+ ++IPriv;
+ ++ILHS;
+ ++IRHS;
+ }
+ };
+ RegionCodeGenTy RCG(CodeGen);
+ NVPTXActionTy Action(
+ nullptr, llvm::None,
+ createNVPTXRuntimeFunction(OMPRTL_NVPTX__kmpc_end_reduce_nowait),
+ EndArgs);
+ RCG.setAction(Action);
+ RCG(CGF);
+ CGF.EmitBranch(DefaultBB);
+ CGF.EmitBlock(DefaultBB, /*IsFinished=*/true);
+}
Index: lib/CodeGen/CGStmtOpenMP.cpp
===================================================================
--- lib/CodeGen/CGStmtOpenMP.cpp
+++ lib/CodeGen/CGStmtOpenMP.cpp
@@ -1190,7 +1190,7 @@
}
void CodeGenFunction::EmitOMPReductionClauseFinal(
- const OMPExecutableDirective &D) {
+ const OMPExecutableDirective &D, const OpenMPDirectiveKind ReductionKind) {
if (!HaveInsertPoint())
return;
llvm::SmallVector<const Expr *, 8> Privates;
@@ -1213,7 +1213,7 @@
D.getSingleClause<OMPNowaitClause>() ||
isOpenMPParallelDirective(D.getDirectiveKind()) ||
D.getDirectiveKind() == OMPD_simd,
- D.getDirectiveKind() == OMPD_simd);
+ D.getDirectiveKind() == OMPD_simd, ReductionKind);
}
}
@@ -1295,7 +1295,7 @@
CGF.EmitOMPReductionClauseInit(S, PrivateScope);
(void)PrivateScope.Privatize();
CGF.EmitStmt(cast<CapturedStmt>(S.getAssociatedStmt())->getCapturedStmt());
- CGF.EmitOMPReductionClauseFinal(S);
+ CGF.EmitOMPReductionClauseFinal(S, OMPD_parallel);
};
emitCommonOMPParallelDirective(*this, S, OMPD_parallel, CodeGen);
emitPostUpdateForReductionClause(
@@ -1708,7 +1708,7 @@
// Emit final copy of the lastprivate variables at the end of loops.
if (HasLastprivateClause)
CGF.EmitOMPLastprivateClauseFinal(S, /*NoFinals=*/true);
- CGF.EmitOMPReductionClauseFinal(S);
+ CGF.EmitOMPReductionClauseFinal(S, OMPD_simd);
emitPostUpdateForReductionClause(
CGF, S, [](CodeGenFunction &) -> llvm::Value * { return nullptr; });
}
@@ -2244,7 +2244,9 @@
CGF.EmitLoadOfScalar(IL, S.getLocStart()));
});
}
- EmitOMPReductionClauseFinal(S);
+ EmitOMPReductionClauseFinal(S, isOpenMPSimdDirective(S.getDirectiveKind())
+ ? OMPD_parallel_for_simd
+ : OMPD_parallel);
// Emit post-update of the reduction variables if IsLastIter != 0.
emitPostUpdateForReductionClause(
*this, S, [&](CodeGenFunction &CGF) -> llvm::Value * {
@@ -2419,7 +2421,7 @@
CGF.CGM.getOpenMPRuntime().emitForStaticFinish(CGF, S.getLocEnd());
};
CGF.OMPCancelStack.emitExit(CGF, S.getDirectiveKind(), CodeGen);
- CGF.EmitOMPReductionClauseFinal(S);
+ CGF.EmitOMPReductionClauseFinal(S, OMPD_parallel);
// Emit post-update of the reduction variables if IsLastIter != 0.
emitPostUpdateForReductionClause(
CGF, S, [&](CodeGenFunction &CGF) -> llvm::Value * {
@@ -3817,11 +3819,19 @@
// Get the captured statement associated with the 'parallel' region.
auto *CS = S.getCapturedStmt(OMPD_parallel);
Action.Enter(CGF);
- auto &&CodeGen = [CS](CodeGenFunction &CGF, PrePostActionTy &) {
+ auto &&CodeGen = [&S, CS](CodeGenFunction &CGF, PrePostActionTy &) {
+ CodeGenFunction::OMPPrivateScope PrivateScope(CGF);
+ (void)CGF.EmitOMPFirstprivateClause(S, PrivateScope);
+ CGF.EmitOMPPrivateClause(S, PrivateScope);
+ CGF.EmitOMPReductionClauseInit(S, PrivateScope);
+ (void)PrivateScope.Privatize();
// TODO: Add support for clauses.
CGF.EmitStmt(CS->getCapturedStmt());
+ CGF.EmitOMPReductionClauseFinal(S, OMPD_parallel);
};
emitCommonOMPParallelDirective(CGF, S, OMPD_parallel, CodeGen);
+ emitPostUpdateForReductionClause(
+ CGF, S, [](CodeGenFunction &) -> llvm::Value * { return nullptr; });
}
void CodeGenFunction::EmitOMPTargetParallelDeviceFunction(
Index: lib/CodeGen/CodeGenFunction.h
===================================================================
--- lib/CodeGen/CodeGenFunction.h
+++ lib/CodeGen/CodeGenFunction.h
@@ -2638,7 +2638,9 @@
/// the end of the directive.
///
/// \param D Directive that has at least one 'reduction' directives.
- void EmitOMPReductionClauseFinal(const OMPExecutableDirective &D);
+ /// \param ReductionKind The kind of reduction to perform.
+ void EmitOMPReductionClauseFinal(const OMPExecutableDirective &D,
+ const OpenMPDirectiveKind ReductionKind);
/// \brief Emit initial code for linear variables. Creates private copies
/// and initializes them with the values according to OpenMP standard.
///
Index: test/OpenMP/nvptx_target_parallel_reduction_codegen.cpp
===================================================================
--- /dev/null
+++ test/OpenMP/nvptx_target_parallel_reduction_codegen.cpp
@@ -0,0 +1,830 @@
+// Test target codegen - host bc file has to be created first.
+// RUN: %clang_cc1 -verify -fopenmp -x c++ -triple powerpc64le-unknown-unknown -fopenmp-targets=nvptx64-nvidia-cuda -emit-llvm-bc %s -o %t-ppc-host.bc
+// RUN: %clang_cc1 -verify -fopenmp -x c++ -triple nvptx64-unknown-unknown -fopenmp-targets=nvptx64-nvidia-cuda -emit-llvm %s -fopenmp-is-device -fopenmp-host-ir-file-path %t-ppc-host.bc -o - | FileCheck %s --check-prefix CHECK --check-prefix CHECK-64
+// RUN: %clang_cc1 -verify -fopenmp -x c++ -triple i386-unknown-unknown -fopenmp-targets=nvptx-nvidia-cuda -emit-llvm-bc %s -o %t-x86-host.bc
+// RUN: %clang_cc1 -verify -fopenmp -x c++ -triple nvptx-unknown-unknown -fopenmp-targets=nvptx-nvidia-cuda -emit-llvm %s -fopenmp-is-device -fopenmp-host-ir-file-path %t-x86-host.bc -o - | FileCheck %s --check-prefix CHECK --check-prefix CHECK-32
+// RUN: %clang_cc1 -verify -fopenmp -fexceptions -fcxx-exceptions -x c++ -triple nvptx-unknown-unknown -fopenmp-targets=nvptx-nvidia-cuda -emit-llvm %s -fopenmp-is-device -fopenmp-host-ir-file-path %t-x86-host.bc -o - | FileCheck %s --check-prefix CHECK --check-prefix CHECK-32
+// expected-no-diagnostics
+#ifndef HEADER
+#define HEADER
+
+// Check for the data transfer medium in shared memory to transfer the reduction list to the first warp.
+// CHECK-DAG: [[TRANSFER_STORAGE:@.+]] = common addrspace([[SHARED_ADDRSPACE:[0-9]+]]) global [32 x i64]
+
+// Check that the execution mode of all 3 target regions is set to Spmd Mode.
+// CHECK-DAG: {{@__omp_offloading_.+l27}}_exec_mode = weak constant i8 0
+// CHECK-DAG: {{@__omp_offloading_.+l32}}_exec_mode = weak constant i8 0
+// CHECK-DAG: {{@__omp_offloading_.+l38}}_exec_mode = weak constant i8 0
+
+template<typename tx>
+tx ftemplate(int n) {
+ int a;
+ short b;
+ tx c;
+ float d;
+ double e;
+
+ #pragma omp target parallel reduction(+: e) map(tofrom: e)
+ {
+ e += 5;
+ }
+
+ #pragma omp target parallel reduction(^: c) reduction(*: d) map(tofrom: c,d)
+ {
+ c ^= 2;
+ d *= 33;
+ }
+
+ #pragma omp target parallel reduction(|: a) reduction(max: b) map(tofrom: a,b)
+ {
+ a |= 1;
+ b = 99 > b ? 99 : b;
+ }
+
+ return a+b+c+d+e;
+}
+
+int bar(int n){
+ int a = 0;
+
+ a += ftemplate<char>(n);
+
+ return a;
+}
+
+ // CHECK: define {{.*}}void {{@__omp_offloading_.+template.+l27}}(
+ //
+ // CHECK: call void @__kmpc_spmd_kernel_init(
+ // CHECK: br label {{%?}}[[EXECUTE:.+]]
+ //
+ // CHECK: [[EXECUTE]]
+ // CHECK: {{call|invoke}} void [[PFN:@.+]](i32*
+ // CHECK: call void @__kmpc_spmd_kernel_deinit()
+ //
+ //
+ // define internal void [[PFN]](
+ // CHECK: store double {{[0\.e\+]+}}, double* [[E:%.+]], align
+ // CHECK: [[EV:%.+]] = load double, double* [[E]], align
+ // CHECK: [[ADD:%.+]] = fadd double [[EV]], 5
+ // CHECK: store double [[ADD]], double* [[E]], align
+ // CHECK: [[PTR1:%.+]] = getelementptr inbounds [[RLT:.+]], [1 x i8*]* [[RL:%.+]], i{{32|64}} 0, i{{32|64}} 0
+ // CHECK: [[E_CAST:%.+]] = bitcast double* [[E]] to i8*
+ // CHECK: store i8* [[E_CAST]], i8** [[PTR1]], align
+ // CHECK: [[ARG_RL:%.+]] = bitcast [[RLT]]* [[RL]] to i8*
+ // CHECK: [[RET:%.+]] = call i32 @__kmpc_nvptx_parallel_reduce_nowait(i32 {{.+}}, i32 1, i{{32|64}} {{4|8}}, i8* [[ARG_RL]], void (i8*, i16, i16, i16)* [[SHUFFLE_REDUCE_FN:@.+]], void (i8*, i32)* [[WARP_COPY_FN:@.+]])
+ // CHECK: switch i32 [[RET]], label {{%?}}[[DEFAULTLABEL:.+]] [
+ // CHECK: i32 1, label {{%?}}[[REDLABEL:.+]]
+
+ // CHECK: [[REDLABEL]]
+ // CHECK: [[E_INV:%.+]] = load double, double* [[E_IN:%.+]], align
+ // CHECK: [[EV:%.+]] = load double, double* [[E]], align
+ // CHECK: [[ADD:%.+]] = fadd double [[E_INV]], [[EV]]
+ // CHECK: store double [[ADD]], double* [[E_IN]], align
+ // CHECK: call void @__kmpc_nvptx_end_reduce_nowait(
+ // CHECK: br label %[[DEFAULTLABEL]]
+ //
+ // CHECK: [[DEFAULTLABEL]]
+ // CHECK: ret
+
+ //
+ // Reduction function
+ // CHECK: define internal void [[REDUCTION_FUNC:@.+]](i8*, i8*)
+ // CHECK: [[VAR_RHS_REF:%.+]] = getelementptr inbounds [[RLT]], [[RLT]]* [[RED_LIST_RHS:%.+]], i{{32|64}} 0, i{{32|64}} 0
+ // CHECK: [[VAR_RHS_VOID:%.+]] = load i8*, i8** [[VAR_RHS_REF]],
+ // CHECK: [[VAR_RHS:%.+]] = bitcast i8* [[VAR_RHS_VOID]] to double*
+ //
+ // CHECK: [[VAR_LHS_REF:%.+]] = getelementptr inbounds [[RLT]], [[RLT]]* [[RED_LIST_LHS:%.+]], i{{32|64}} 0, i{{32|64}} 0
+ // CHECK: [[VAR_LHS_VOID:%.+]] = load i8*, i8** [[VAR_LHS_REF]],
+ // CHECK: [[VAR_LHS:%.+]] = bitcast i8* [[VAR_LHS_VOID]] to double*
+ //
+ // CHECK: [[VAR_LHS_VAL:%.+]] = load double, double* [[VAR_LHS]],
+ // CHECK: [[VAR_RHS_VAL:%.+]] = load double, double* [[VAR_RHS]],
+ // CHECK: [[RES:%.+]] = fadd double [[VAR_LHS_VAL]], [[VAR_RHS_VAL]]
+ // CHECK: store double [[RES]], double* [[VAR_LHS]],
+ // CHECK: ret void
+
+ //
+ // Shuffle and reduce function
+ // CHECK: define internal void [[SHUFFLE_REDUCE_FN]](i8*, i16 {{.*}}, i16 {{.*}}, i16 {{.*}})
+ // CHECK: [[REMOTE_RED_LIST:%.+]] = alloca [[RLT]], align
+ // CHECK: [[REMOTE_ELT:%.+]] = alloca double
+ //
+ // CHECK: [[LANEID:%.+]] = load i16, i16* {{.+}}, align
+ // CHECK: [[LANEOFFSET:%.+]] = load i16, i16* {{.+}}, align
+ // CHECK: [[ALGVER:%.+]] = load i16, i16* {{.+}}, align
+ //
+ // CHECK: [[ELT_REF:%.+]] = getelementptr inbounds [[RLT]], [[RLT]]* [[RED_LIST:%.+]], i{{32|64}} 0, i{{32|64}} 0
+ // CHECK: [[ELT_VOID:%.+]] = load i8*, i8** [[ELT_REF]],
+ // CHECK: [[REMOTE_ELT_REF:%.+]] = getelementptr inbounds [[RLT]], [[RLT]]* [[REMOTE_RED_LIST:%.+]], i{{32|64}} 0, i{{32|64}} 0
+ // CHECK: [[ELT:%.+]] = bitcast i8* [[ELT_VOID]] to double*
+ // CHECK: [[ELT_VAL:%.+]] = load double, double* [[ELT]], align
+ //
+ // CHECK: [[ELT_CAST:%.+]] = bitcast double [[ELT_VAL]] to i64
+ // CHECK: [[WS32:%.+]] = call i32 @llvm.nvvm.read.ptx.sreg.warpsize()
+ // CHECK: [[WS:%.+]] = trunc i32 [[WS32]] to i16
+ // CHECK: [[REMOTE_ELT_VAL64:%.+]] = call i64 @__kmpc_shuffle_int64(i64 [[ELT_CAST]], i16 [[LANEOFFSET]], i16 [[WS]])
+ // CHECK: [[REMOTE_ELT_VAL:%.+]] = bitcast i64 [[REMOTE_ELT_VAL64]] to double
+ //
+ // CHECK: store double [[REMOTE_ELT_VAL]], double* [[REMOTE_ELT]], align
+ // CHECK: [[REMOTE_ELT_VOID:%.+]] = bitcast double* [[REMOTE_ELT]] to i8*
+ // CHECK: store i8* [[REMOTE_ELT_VOID]], i8** [[REMOTE_ELT_REF]], align
+ //
+ // Condition to reduce
+ // CHECK: [[CONDALG0:%.+]] = icmp eq i16 [[ALGVER]], 0
+ //
+ // CHECK: [[COND1:%.+]] = icmp eq i16 [[ALGVER]], 1
+ // CHECK: [[COND2:%.+]] = icmp ult i16 [[LANEID]], [[LANEOFFSET]]
+ // CHECK: [[CONDALG1:%.+]] = and i1 [[COND1]], [[COND2]]
+ //
+ // CHECK: [[COND3:%.+]] = icmp eq i16 [[ALGVER]], 2
+ // CHECK: [[COND4:%.+]] = and i16 [[LANEID]], 1
+ // CHECK: [[COND5:%.+]] = icmp eq i16 [[COND4]], 0
+ // CHECK: [[COND6:%.+]] = and i1 [[COND3]], [[COND5]]
+ // CHECK: [[COND7:%.+]] = icmp sgt i16 [[LANEOFFSET]], 0
+ // CHECK: [[CONDALG2:%.+]] = and i1 [[COND6]], [[COND7]]
+ //
+ // CHECK: [[COND8:%.+]] = or i1 [[CONDALG0]], [[CONDALG1]]
+ // CHECK: [[SHOULD_REDUCE:%.+]] = or i1 [[COND8]], [[CONDALG2]]
+ // CHECK: br i1 [[SHOULD_REDUCE]], label {{%?}}[[DO_REDUCE:.+]], label {{%?}}[[REDUCE_ELSE:.+]]
+ //
+ // CHECK: [[DO_REDUCE]]
+ // CHECK: [[RED_LIST1_VOID:%.+]] = bitcast [[RLT]]* [[RED_LIST]] to i8*
+ // CHECK: [[RED_LIST2_VOID:%.+]] = bitcast [[RLT]]* [[REMOTE_RED_LIST]] to i8*
+ // CHECK: call void [[REDUCTION_FUNC]](i8* [[RED_LIST1_VOID]], i8* [[RED_LIST2_VOID]])
+ // CHECK: br label {{%?}}[[REDUCE_CONT:.+]]
+ //
+ // CHECK: [[REDUCE_ELSE]]
+ // CHECK: br label {{%?}}[[REDUCE_CONT]]
+ //
+ // CHECK: [[REDUCE_CONT]]
+ // Now check if we should just copy over the remote reduction list
+ // CHECK: [[COND1:%.+]] = icmp eq i16 [[ALGVER]], 1
+ // CHECK: [[COND2:%.+]] = icmp uge i16 [[LANEID]], [[LANEOFFSET]]
+ // CHECK: [[SHOULD_COPY:%.+]] = and i1 [[COND1]], [[COND2]]
+ // CHECK: br i1 [[SHOULD_COPY]], label {{%?}}[[DO_COPY:.+]], label {{%?}}[[COPY_ELSE:.+]]
+ //
+ // CHECK: [[DO_COPY]]
+ // CHECK: [[REMOTE_ELT_REF:%.+]] = getelementptr inbounds [[RLT]], [[RLT]]* [[REMOTE_RED_LIST]], i{{32|64}} 0, i{{32|64}} 0
+ // CHECK: [[REMOTE_ELT_VOID:%.+]] = load i8*, i8** [[REMOTE_ELT_REF]],
+ // CHECK: [[ELT_REF:%.+]] = getelementptr inbounds [[RLT]], [[RLT]]* [[RED_LIST]], i{{32|64}} 0, i{{32|64}} 0
+ // CHECK: [[ELT_VOID:%.+]] = load i8*, i8** [[ELT_REF]],
+ // CHECK: [[ELT:%.+]] = bitcast i8* [[ELT_VOID]] to double*
+ // CHECK: [[REMOTE_ELT:%.+]] = bitcast i8* [[REMOTE_ELT_VOID]] to double*
+ // CHECK: [[REMOTE_ELT_VAL:%.+]] = load double, double* [[REMOTE_ELT]], align
+ // CHECK: store double [[REMOTE_ELT_VAL]], double* [[ELT]], align
+ // CHECK: br label {{%?}}[[COPY_CONT:.+]]
+ //
+ // CHECK: [[COPY_ELSE]]
+ // CHECK: br label {{%?}}[[COPY_CONT]]
+ //
+ // CHECK: [[COPY_CONT]]
+ // CHECK: void
+
+ //
+ // Inter warp copy function
+ // CHECK: define internal void [[WARP_COPY_FN]](i8*, i32)
+ // CHECK-DAG: [[LANEID:%.+]] = and i32 {{.+}}, 31
+ // CHECK-DAG: [[WARPID:%.+]] = ashr i32 {{.+}}, 5
+ // CHECK-DAG: [[RED_LIST:%.+]] = bitcast i8* {{.+}} to [[RLT]]*
+ // CHECK: [[IS_WARP_MASTER:%.+]] = icmp eq i32 [[LANEID]], 0
+ // CHECK: br i1 [[IS_WARP_MASTER]], label {{%?}}[[DO_COPY:.+]], label {{%?}}[[COPY_ELSE:.+]]
+ //
+ // [[DO_COPY]]
+ // CHECK: [[ELT_REF:%.+]] = getelementptr inbounds [[RLT]], [[RLT]]* [[RED_LIST]], i{{32|64}} 0, i{{32|64}} 0
+ // CHECK: [[ELT_VOID:%.+]] = load i8*, i8** [[ELT_REF]],
+ // CHECK: [[ELT:%.+]] = bitcast i8* [[ELT_VOID]] to double*
+ // CHECK: [[ELT_VAL:%.+]] = load double, double* [[ELT]], align
+ //
+ // CHECK: [[MEDIUM_ELT64:%.+]] = getelementptr inbounds [32 x i64], [32 x i64] addrspace([[SHARED_ADDRSPACE]])* [[TRANSFER_STORAGE]], i64 0, i32 [[WARPID]]
+ // CHECK: [[MEDIUM_ELT:%.+]] = bitcast i64 addrspace([[SHARED_ADDRSPACE]])* [[MEDIUM_ELT64]] to double addrspace([[SHARED_ADDRSPACE]])*
+ // CHECK: store double [[ELT_VAL]], double addrspace([[SHARED_ADDRSPACE]])* [[MEDIUM_ELT]], align
+ // CHECK: br label {{%?}}[[COPY_CONT:.+]]
+ //
+ // CHECK: [[COPY_ELSE]]
+ // CHECK: br label {{%?}}[[COPY_CONT]]
+ //
+ // Barrier after copy to shared memory storage medium.
+ // CHECK: [[COPY_CONT]]
+ // CHECK: [[WS:%.+]] = call i32 @llvm.nvvm.read.ptx.sreg.warpsize()
+ // CHECK: [[ACTIVE_THREADS:%.+]] = mul nsw i32 [[ACTIVE_WARPS:%.+]], [[WS]]
+ // CHECK: call void @llvm.nvvm.barrier(i32 1, i32 [[ACTIVE_THREADS]])
+ //
+ // Read into warp 0.
+ // CHECK: [[IS_W0_ACTIVE_THREAD:%.+]] = icmp ult i32 [[TID:%.+]], [[ACTIVE_WARPS]]
+ // CHECK: br i1 [[IS_W0_ACTIVE_THREAD]], label {{%?}}[[DO_READ:.+]], label {{%?}}[[READ_ELSE:.+]]
+ //
+ // CHECK: [[DO_READ]]
+ // CHECK: [[MEDIUM_ELT64:%.+]] = getelementptr inbounds [32 x i64], [32 x i64] addrspace([[SHARED_ADDRSPACE]])* [[TRANSFER_STORAGE]], i64 0, i32 [[TID]]
+ // CHECK: [[MEDIUM_ELT:%.+]] = bitcast i64 addrspace([[SHARED_ADDRSPACE]])* [[MEDIUM_ELT64]] to double addrspace([[SHARED_ADDRSPACE]])*
+ // CHECK: [[MEDIUM_ELT_VAL:%.+]] = load double, double addrspace([[SHARED_ADDRSPACE]])* [[MEDIUM_ELT]], align
+ // CHECK: [[ELT_REF:%.+]] = getelementptr inbounds [[RLT]], [[RLT]]* [[RED_LIST:%.+]], i{{32|64}} 0, i{{32|64}} 0
+ // CHECK: [[ELT_VOID:%.+]] = load i8*, i8** [[ELT_REF]],
+ // CHECK: [[ELT:%.+]] = bitcast i8* [[ELT_VOID]] to double*
+ // CHECK: store double [[MEDIUM_ELT_VAL]], double* [[ELT]], align
+ // CHECK: br label {{%?}}[[READ_CONT:.+]]
+ //
+ // CHECK: [[READ_ELSE]]
+ // CHECK: br label {{%?}}[[READ_CONT]]
+ //
+ // CHECK: [[READ_CONT]]
+ // CHECK: call void @llvm.nvvm.barrier(i32 1, i32 [[ACTIVE_THREADS]])
+ // CHECK: ret
+
+
+
+
+
+
+
+
+
+
+ // CHECK: define {{.*}}void {{@__omp_offloading_.+template.+l32}}(
+ //
+ // CHECK: call void @__kmpc_spmd_kernel_init(
+ // CHECK: br label {{%?}}[[EXECUTE:.+]]
+ //
+ // CHECK: [[EXECUTE]]
+ // CHECK: {{call|invoke}} void [[PFN1:@.+]](i32*
+ // CHECK: call void @__kmpc_spmd_kernel_deinit()
+ //
+ //
+ // define internal void [[PFN1]](
+ // CHECK: store float {{1\.[0e\+]+}}, float* [[D:%.+]], align
+ // CHECK: [[C_VAL:%.+]] = load i8, i8* [[C:%.+]], align
+ // CHECK: [[CONV:%.+]] = sext i8 [[C_VAL]] to i32
+ // CHECK: [[XOR:%.+]] = xor i32 [[CONV]], 2
+ // CHECK: [[TRUNC:%.+]] = trunc i32 [[XOR]] to i8
+ // CHECK: store i8 [[TRUNC]], i8* [[C]], align
+ // CHECK: [[DV:%.+]] = load float, float* [[D]], align
+ // CHECK: [[MUL:%.+]] = fmul float [[DV]], {{[0-9e\.\+]+}}
+ // CHECK: store float [[MUL]], float* [[D]], align
+ // CHECK: [[PTR1:%.+]] = getelementptr inbounds [[RLT:.+]], [2 x i8*]* [[RL:%.+]], i{{32|64}} 0, i{{32|64}} 0
+ // CHECK: store i8* [[C]], i8** [[PTR1]], align
+ // CHECK: [[PTR2:%.+]] = getelementptr inbounds [[RLT]], [[RLT]]* [[RL]], i{{32|64}} 0, i{{32|64}} 1
+ // CHECK: [[D_CAST:%.+]] = bitcast float* [[D]] to i8*
+ // CHECK: store i8* [[D_CAST]], i8** [[PTR2]], align
+ // CHECK: [[ARG_RL:%.+]] = bitcast [[RLT]]* [[RL]] to i8*
+ // CHECK: [[RET:%.+]] = call i32 @__kmpc_nvptx_parallel_reduce_nowait(i32 {{.+}}, i32 2, i{{32|64}} {{8|16}}, i8* [[ARG_RL]], void (i8*, i16, i16, i16)* [[SHUFFLE_REDUCE_FN:@.+]], void (i8*, i32)* [[WARP_COPY_FN:@.+]])
+ // CHECK: switch i32 [[RET]], label {{%?}}[[DEFAULTLABEL:.+]] [
+ // CHECK: i32 1, label {{%?}}[[REDLABEL:.+]]
+
+ // CHECK: [[REDLABEL]]
+ // CHECK: [[C_INV8:%.+]] = load i8, i8* [[C_IN:%.+]], align
+ // CHECK: [[C_INV:%.+]] = sext i8 [[C_INV8]] to i32
+ // CHECK: [[CV8:%.+]] = load i8, i8* [[C]], align
+ // CHECK: [[CV:%.+]] = sext i8 [[CV8]] to i32
+ // CHECK: [[XOR:%.+]] = xor i32 [[C_INV]], [[CV]]
+ // CHECK: [[TRUNC:%.+]] = trunc i32 [[XOR]] to i8
+ // CHECK: store i8 [[TRUNC]], i8* [[C_IN]], align
+ // CHECK: [[D_INV:%.+]] = load float, float* [[D_IN:%.+]], align
+ // CHECK: [[DV:%.+]] = load float, float* [[D]], align
+ // CHECK: [[MUL:%.+]] = fmul float [[D_INV]], [[DV]]
+ // CHECK: store float [[MUL]], float* [[D_IN]], align
+ // CHECK: call void @__kmpc_nvptx_end_reduce_nowait(
+ // CHECK: br label %[[DEFAULTLABEL]]
+ //
+ // CHECK: [[DEFAULTLABEL]]
+ // CHECK: ret
+
+ //
+ // Reduction function
+ // CHECK: define internal void [[REDUCTION_FUNC:@.+]](i8*, i8*)
+ // CHECK: [[VAR1_RHS_REF:%.+]] = getelementptr inbounds [[RLT]], [[RLT]]* [[RED_LIST_RHS:%.+]], i{{32|64}} 0, i{{32|64}} 0
+ // CHECK: [[VAR1_RHS:%.+]] = load i8*, i8** [[VAR1_RHS_REF]],
+ //
+ // CHECK: [[VAR1_LHS_REF:%.+]] = getelementptr inbounds [[RLT]], [[RLT]]* [[RED_LIST_LHS:%.+]], i{{32|64}} 0, i{{32|64}} 0
+ // CHECK: [[VAR1_LHS:%.+]] = load i8*, i8** [[VAR1_LHS_REF]],
+ //
+ // CHECK: [[VAR2_RHS_REF:%.+]] = getelementptr inbounds [[RLT]], [[RLT]]* [[RED_LIST_RHS]], i{{32|64}} 0, i{{32|64}} 1
+ // CHECK: [[VAR2_RHS_VOID:%.+]] = load i8*, i8** [[VAR2_RHS_REF]],
+ // CHECK: [[VAR2_RHS:%.+]] = bitcast i8* [[VAR2_RHS_VOID]] to float*
+ //
+ // CHECK: [[VAR2_LHS_REF:%.+]] = getelementptr inbounds [[RLT]], [[RLT]]* [[RED_LIST_LHS]], i{{32|64}} 0, i{{32|64}} 1
+ // CHECK: [[VAR2_LHS_VOID:%.+]] = load i8*, i8** [[VAR2_LHS_REF]],
+ // CHECK: [[VAR2_LHS:%.+]] = bitcast i8* [[VAR2_LHS_VOID]] to float*
+ //
+ // CHECK: [[VAR1_LHS_VAL8:%.+]] = load i8, i8* [[VAR1_LHS]],
+ // CHECK: [[VAR1_LHS_VAL:%.+]] = sext i8 [[VAR1_LHS_VAL8]] to i32
+ // CHECK: [[VAR1_RHS_VAL8:%.+]] = load i8, i8* [[VAR1_RHS]],
+ // CHECK: [[VAR1_RHS_VAL:%.+]] = sext i8 [[VAR1_RHS_VAL8]] to i32
+ // CHECK: [[XOR:%.+]] = xor i32 [[VAR1_LHS_VAL]], [[VAR1_RHS_VAL]]
+ // CHECK: [[RES:%.+]] = trunc i32 [[XOR]] to i8
+ // CHECK: store i8 [[RES]], i8* [[VAR1_LHS]],
+ //
+ // CHECK: [[VAR2_LHS_VAL:%.+]] = load float, float* [[VAR2_LHS]],
+ // CHECK: [[VAR2_RHS_VAL:%.+]] = load float, float* [[VAR2_RHS]],
+ // CHECK: [[RES:%.+]] = fmul float [[VAR2_LHS_VAL]], [[VAR2_RHS_VAL]]
+ // CHECK: store float [[RES]], float* [[VAR2_LHS]],
+ // CHECK: ret void
+
+ //
+ // Shuffle and reduce function
+ // CHECK: define internal void [[SHUFFLE_REDUCE_FN]](i8*, i16 {{.*}}, i16 {{.*}}, i16 {{.*}})
+ // CHECK: [[REMOTE_RED_LIST:%.+]] = alloca [[RLT]], align
+ // CHECK: [[REMOTE_ELT1:%.+]] = alloca i8
+ // CHECK: [[REMOTE_ELT2:%.+]] = alloca float
+ //
+ // CHECK: [[LANEID:%.+]] = load i16, i16* {{.+}}, align
+ // CHECK: [[LANEOFFSET:%.+]] = load i16, i16* {{.+}}, align
+ // CHECK: [[ALGVER:%.+]] = load i16, i16* {{.+}}, align
+ //
+ // CHECK: [[ELT_REF:%.+]] = getelementptr inbounds [[RLT]], [[RLT]]* [[RED_LIST:%.+]], i{{32|64}} 0, i{{32|64}} 0
+ // CHECK: [[ELT_VOID:%.+]] = load i8*, i8** [[ELT_REF]],
+ // CHECK: [[REMOTE_ELT_REF:%.+]] = getelementptr inbounds [[RLT]], [[RLT]]* [[REMOTE_RED_LIST:%.+]], i{{32|64}} 0, i{{32|64}} 0
+ // CHECK: [[ELT_VAL:%.+]] = load i8, i8* [[ELT_VOID]], align
+ //
+ // CHECK: [[ELT_CAST:%.+]] = sext i8 [[ELT_VAL]] to i32
+ // CHECK: [[WS32:%.+]] = call i32 @llvm.nvvm.read.ptx.sreg.warpsize()
+ // CHECK: [[WS:%.+]] = trunc i32 [[WS32]] to i16
+ // CHECK: [[REMOTE_ELT1_VAL32:%.+]] = call i32 @__kmpc_shuffle_int32(i32 [[ELT_CAST]], i16 [[LANEOFFSET]], i16 [[WS]])
+ // CHECK: [[REMOTE_ELT1_VAL:%.+]] = trunc i32 [[REMOTE_ELT1_VAL32]] to i8
+ //
+ // CHECK: store i8 [[REMOTE_ELT1_VAL]], i8* [[REMOTE_ELT1]], align
+ // CHECK: store i8* [[REMOTE_ELT1]], i8** [[REMOTE_ELT_REF]], align
+ //
+ // CHECK: [[ELT_REF:%.+]] = getelementptr inbounds [[RLT]], [[RLT]]* [[RED_LIST]], i{{32|64}} 0, i{{32|64}} 1
+ // CHECK: [[ELT_VOID:%.+]] = load i8*, i8** [[ELT_REF]],
+ // CHECK: [[REMOTE_ELT_REF:%.+]] = getelementptr inbounds [[RLT]], [[RLT]]* [[REMOTE_RED_LIST]], i{{32|64}} 0, i{{32|64}} 1
+ // CHECK: [[ELT:%.+]] = bitcast i8* [[ELT_VOID]] to float*
+ // CHECK: [[ELT_VAL:%.+]] = load float, float* [[ELT]], align
+ //
+ // CHECK: [[ELT_CAST:%.+]] = bitcast float [[ELT_VAL]] to i32
+ // CHECK: [[WS32:%.+]] = call i32 @llvm.nvvm.read.ptx.sreg.warpsize()
+ // CHECK: [[WS:%.+]] = trunc i32 [[WS32]] to i16
+ // CHECK: [[REMOTE_ELT2_VAL32:%.+]] = call i32 @__kmpc_shuffle_int32(i32 [[ELT_CAST]], i16 [[LANEOFFSET]], i16 [[WS]])
+ // CHECK: [[REMOTE_ELT2_VAL:%.+]] = bitcast i32 [[REMOTE_ELT2_VAL32]] to float
+ //
+ // CHECK: store float [[REMOTE_ELT2_VAL]], float* [[REMOTE_ELT2]], align
+ // CHECK: [[REMOTE_ELT2C:%.+]] = bitcast float* [[REMOTE_ELT2]] to i8*
+ // CHECK: store i8* [[REMOTE_ELT2C]], i8** [[REMOTE_ELT_REF]], align
+ //
+ // Condition to reduce
+ // CHECK: [[CONDALG0:%.+]] = icmp eq i16 [[ALGVER]], 0
+ //
+ // CHECK: [[COND1:%.+]] = icmp eq i16 [[ALGVER]], 1
+ // CHECK: [[COND2:%.+]] = icmp ult i16 [[LANEID]], [[LANEOFFSET]]
+ // CHECK: [[CONDALG1:%.+]] = and i1 [[COND1]], [[COND2]]
+ //
+ // CHECK: [[COND3:%.+]] = icmp eq i16 [[ALGVER]], 2
+ // CHECK: [[COND4:%.+]] = and i16 [[LANEID]], 1
+ // CHECK: [[COND5:%.+]] = icmp eq i16 [[COND4]], 0
+ // CHECK: [[COND6:%.+]] = and i1 [[COND3]], [[COND5]]
+ // CHECK: [[COND7:%.+]] = icmp sgt i16 [[LANEOFFSET]], 0
+ // CHECK: [[CONDALG2:%.+]] = and i1 [[COND6]], [[COND7]]
+ //
+ // CHECK: [[COND8:%.+]] = or i1 [[CONDALG0]], [[CONDALG1]]
+ // CHECK: [[SHOULD_REDUCE:%.+]] = or i1 [[COND8]], [[CONDALG2]]
+ // CHECK: br i1 [[SHOULD_REDUCE]], label {{%?}}[[DO_REDUCE:.+]], label {{%?}}[[REDUCE_ELSE:.+]]
+ //
+ // CHECK: [[DO_REDUCE]]
+ // CHECK: [[RED_LIST1_VOID:%.+]] = bitcast [[RLT]]* [[RED_LIST]] to i8*
+ // CHECK: [[RED_LIST2_VOID:%.+]] = bitcast [[RLT]]* [[REMOTE_RED_LIST]] to i8*
+ // CHECK: call void [[REDUCTION_FUNC]](i8* [[RED_LIST1_VOID]], i8* [[RED_LIST2_VOID]])
+ // CHECK: br label {{%?}}[[REDUCE_CONT:.+]]
+ //
+ // CHECK: [[REDUCE_ELSE]]
+ // CHECK: br label {{%?}}[[REDUCE_CONT]]
+ //
+ // CHECK: [[REDUCE_CONT]]
+ // Now check if we should just copy over the remote reduction list
+ // CHECK: [[COND1:%.+]] = icmp eq i16 [[ALGVER]], 1
+ // CHECK: [[COND2:%.+]] = icmp uge i16 [[LANEID]], [[LANEOFFSET]]
+ // CHECK: [[SHOULD_COPY:%.+]] = and i1 [[COND1]], [[COND2]]
+ // CHECK: br i1 [[SHOULD_COPY]], label {{%?}}[[DO_COPY:.+]], label {{%?}}[[COPY_ELSE:.+]]
+ //
+ // CHECK: [[DO_COPY]]
+ // CHECK: [[REMOTE_ELT_REF:%.+]] = getelementptr inbounds [[RLT]], [[RLT]]* [[REMOTE_RED_LIST]], i{{32|64}} 0, i{{32|64}} 0
+ // CHECK: [[REMOTE_ELT_VOID:%.+]] = load i8*, i8** [[REMOTE_ELT_REF]],
+ // CHECK: [[ELT_REF:%.+]] = getelementptr inbounds [[RLT]], [[RLT]]* [[RED_LIST]], i{{32|64}} 0, i{{32|64}} 0
+ // CHECK: [[ELT_VOID:%.+]] = load i8*, i8** [[ELT_REF]],
+ // CHECK: [[REMOTE_ELT_VAL:%.+]] = load i8, i8* [[REMOTE_ELT_VOID]], align
+ // CHECK: store i8 [[REMOTE_ELT_VAL]], i8* [[ELT_VOID]], align
+ //
+ // CHECK: [[REMOTE_ELT_REF:%.+]] = getelementptr inbounds [[RLT]], [[RLT]]* [[REMOTE_RED_LIST]], i{{32|64}} 0, i{{32|64}} 1
+ // CHECK: [[REMOTE_ELT_VOID:%.+]] = load i8*, i8** [[REMOTE_ELT_REF]],
+ // CHECK: [[ELT_REF:%.+]] = getelementptr inbounds [[RLT]], [[RLT]]* [[RED_LIST]], i{{32|64}} 0, i{{32|64}} 1
+ // CHECK: [[ELT_VOID:%.+]] = load i8*, i8** [[ELT_REF]],
+ // CHECK: [[ELT:%.+]] = bitcast i8* [[ELT_VOID]] to float*
+ // CHECK: [[REMOTE_ELT:%.+]] = bitcast i8* [[REMOTE_ELT_VOID]] to float*
+ // CHECK: [[REMOTE_ELT_VAL:%.+]] = load float, float* [[REMOTE_ELT]], align
+ // CHECK: store float [[REMOTE_ELT_VAL]], float* [[ELT]], align
+ // CHECK: br label {{%?}}[[COPY_CONT:.+]]
+ //
+ // CHECK: [[COPY_ELSE]]
+ // CHECK: br label {{%?}}[[COPY_CONT]]
+ //
+ // CHECK: [[COPY_CONT]]
+ // CHECK: void
+
+ //
+ // Inter warp copy function
+ // CHECK: define internal void [[WARP_COPY_FN]](i8*, i32)
+ // CHECK-DAG: [[LANEID:%.+]] = and i32 {{.+}}, 31
+ // CHECK-DAG: [[WARPID:%.+]] = ashr i32 {{.+}}, 5
+ // CHECK-DAG: [[RED_LIST:%.+]] = bitcast i8* {{.+}} to [[RLT]]*
+ // CHECK: [[IS_WARP_MASTER:%.+]] = icmp eq i32 [[LANEID]], 0
+ // CHECK: br i1 [[IS_WARP_MASTER]], label {{%?}}[[DO_COPY:.+]], label {{%?}}[[COPY_ELSE:.+]]
+ //
+ // [[DO_COPY]]
+ // CHECK: [[ELT_REF:%.+]] = getelementptr inbounds [[RLT]], [[RLT]]* [[RED_LIST]], i{{32|64}} 0, i{{32|64}} 0
+ // CHECK: [[ELT_VOID:%.+]] = load i8*, i8** [[ELT_REF]],
+ // CHECK: [[ELT_VAL:%.+]] = load i8, i8* [[ELT_VOID]], align
+ //
+ // CHECK: [[MEDIUM_ELT64:%.+]] = getelementptr inbounds [32 x i64], [32 x i64] addrspace([[SHARED_ADDRSPACE]])* [[TRANSFER_STORAGE]], i64 0, i32 [[WARPID]]
+ // CHECK: [[MEDIUM_ELT:%.+]] = bitcast i64 addrspace([[SHARED_ADDRSPACE]])* [[MEDIUM_ELT64]] to i8 addrspace([[SHARED_ADDRSPACE]])*
+ // CHECK: store i8 [[ELT_VAL]], i8 addrspace([[SHARED_ADDRSPACE]])* [[MEDIUM_ELT]], align
+ // CHECK: br label {{%?}}[[COPY_CONT:.+]]
+ //
+ // CHECK: [[COPY_ELSE]]
+ // CHECK: br label {{%?}}[[COPY_CONT]]
+ //
+ // Barrier after copy to shared memory storage medium.
+ // CHECK: [[COPY_CONT]]
+ // CHECK: [[WS:%.+]] = call i32 @llvm.nvvm.read.ptx.sreg.warpsize()
+ // CHECK: [[ACTIVE_THREADS:%.+]] = mul nsw i32 [[ACTIVE_WARPS:%.+]], [[WS]]
+ // CHECK: call void @llvm.nvvm.barrier(i32 1, i32 [[ACTIVE_THREADS]])
+ //
+ // Read into warp 0.
+ // CHECK: [[IS_W0_ACTIVE_THREAD:%.+]] = icmp ult i32 [[TID:%.+]], [[ACTIVE_WARPS]]
+ // CHECK: br i1 [[IS_W0_ACTIVE_THREAD]], label {{%?}}[[DO_READ:.+]], label {{%?}}[[READ_ELSE:.+]]
+ //
+ // CHECK: [[DO_READ]]
+ // CHECK: [[MEDIUM_ELT64:%.+]] = getelementptr inbounds [32 x i64], [32 x i64] addrspace([[SHARED_ADDRSPACE]])* [[TRANSFER_STORAGE]], i64 0, i32 [[TID]]
+ // CHECK: [[MEDIUM_ELT:%.+]] = bitcast i64 addrspace([[SHARED_ADDRSPACE]])* [[MEDIUM_ELT64]] to i8 addrspace([[SHARED_ADDRSPACE]])*
+ // CHECK: [[MEDIUM_ELT_VAL:%.+]] = load i8, i8 addrspace([[SHARED_ADDRSPACE]])* [[MEDIUM_ELT]], align
+ // CHECK: [[ELT_REF:%.+]] = getelementptr inbounds [[RLT]], [[RLT]]* [[RED_LIST:%.+]], i{{32|64}} 0, i{{32|64}} 0
+ // CHECK: [[ELT_VOID:%.+]] = load i8*, i8** [[ELT_REF]],
+ // CHECK: store i8 [[MEDIUM_ELT_VAL]], i8* [[ELT_VOID]], align
+ // CHECK: br label {{%?}}[[READ_CONT:.+]]
+ //
+ // CHECK: [[READ_ELSE]]
+ // CHECK: br label {{%?}}[[READ_CONT]]
+ //
+ // CHECK: [[READ_CONT]]
+ // CHECK: call void @llvm.nvvm.barrier(i32 1, i32 [[ACTIVE_THREADS]])
+ // CHECK: [[IS_WARP_MASTER:%.+]] = icmp eq i32 [[LANEID]], 0
+ // CHECK: br i1 [[IS_WARP_MASTER]], label {{%?}}[[DO_COPY:.+]], label {{%?}}[[COPY_ELSE:.+]]
+ //
+ // [[DO_COPY]]
+ // CHECK: [[ELT_REF:%.+]] = getelementptr inbounds [[RLT]], [[RLT]]* [[RED_LIST]], i{{32|64}} 0, i{{32|64}} 1
+ // CHECK: [[ELT_VOID:%.+]] = load i8*, i8** [[ELT_REF]],
+ // CHECK: [[ELT:%.+]] = bitcast i8* [[ELT_VOID]] to float*
+ // CHECK: [[ELT_VAL:%.+]] = load float, float* [[ELT]], align
+ //
+ // CHECK: [[MEDIUM_ELT64:%.+]] = getelementptr inbounds [32 x i64], [32 x i64] addrspace([[SHARED_ADDRSPACE]])* [[TRANSFER_STORAGE]], i64 0, i32 [[WARPID]]
+ // CHECK: [[MEDIUM_ELT:%.+]] = bitcast i64 addrspace([[SHARED_ADDRSPACE]])* [[MEDIUM_ELT64]] to float addrspace([[SHARED_ADDRSPACE]])*
+ // CHECK: store float [[ELT_VAL]], float addrspace([[SHARED_ADDRSPACE]])* [[MEDIUM_ELT]], align
+ // CHECK: br label {{%?}}[[COPY_CONT:.+]]
+ //
+ // CHECK: [[COPY_ELSE]]
+ // CHECK: br label {{%?}}[[COPY_CONT]]
+ //
+ // Barrier after copy to shared memory storage medium.
+ // CHECK: [[COPY_CONT]]
+ // CHECK: [[WS:%.+]] = call i32 @llvm.nvvm.read.ptx.sreg.warpsize()
+ // CHECK: [[ACTIVE_THREADS:%.+]] = mul nsw i32 [[ACTIVE_WARPS:%.+]], [[WS]]
+ // CHECK: call void @llvm.nvvm.barrier(i32 1, i32 [[ACTIVE_THREADS]])
+ //
+ // Read into warp 0.
+ // CHECK: [[IS_W0_ACTIVE_THREAD:%.+]] = icmp ult i32 [[TID:%.+]], [[ACTIVE_WARPS]]
+ // CHECK: br i1 [[IS_W0_ACTIVE_THREAD]], label {{%?}}[[DO_READ:.+]], label {{%?}}[[READ_ELSE:.+]]
+ //
+ // CHECK: [[DO_READ]]
+ // CHECK: [[MEDIUM_ELT64:%.+]] = getelementptr inbounds [32 x i64], [32 x i64] addrspace([[SHARED_ADDRSPACE]])* [[TRANSFER_STORAGE]], i64 0, i32 [[TID]]
+ // CHECK: [[MEDIUM_ELT:%.+]] = bitcast i64 addrspace([[SHARED_ADDRSPACE]])* [[MEDIUM_ELT64]] to float addrspace([[SHARED_ADDRSPACE]])*
+ // CHECK: [[MEDIUM_ELT_VAL:%.+]] = load float, float addrspace([[SHARED_ADDRSPACE]])* [[MEDIUM_ELT]], align
+ // CHECK: [[ELT_REF:%.+]] = getelementptr inbounds [[RLT]], [[RLT]]* [[RED_LIST:%.+]], i{{32|64}} 0, i{{32|64}} 1
+ // CHECK: [[ELT_VOID:%.+]] = load i8*, i8** [[ELT_REF]],
+ // CHECK: [[ELT:%.+]] = bitcast i8* [[ELT_VOID]] to float*
+ // CHECK: store float [[MEDIUM_ELT_VAL]], float* [[ELT]], align
+ // CHECK: br label {{%?}}[[READ_CONT:.+]]
+ //
+ // CHECK: [[READ_ELSE]]
+ // CHECK: br label {{%?}}[[READ_CONT]]
+ //
+ // CHECK: [[READ_CONT]]
+ // CHECK: call void @llvm.nvvm.barrier(i32 1, i32 [[ACTIVE_THREADS]])
+ // CHECK: ret
+
+
+
+
+
+
+
+
+
+
+ // CHECK: define {{.*}}void {{@__omp_offloading_.+template.+l38}}(
+ //
+ // CHECK: call void @__kmpc_spmd_kernel_init(
+ // CHECK: br label {{%?}}[[EXECUTE:.+]]
+ //
+ // CHECK: [[EXECUTE]]
+ // CHECK: {{call|invoke}} void [[PFN2:@.+]](i32*
+ // CHECK: call void @__kmpc_spmd_kernel_deinit()
+ //
+ //
+ // define internal void [[PFN2]](
+ // CHECK: store i32 0, i32* [[A:%.+]], align
+ // CHECK: store i16 -32768, i16* [[B:%.+]], align
+ // CHECK: [[A_VAL:%.+]] = load i32, i32* [[A:%.+]], align
+ // CHECK: [[OR:%.+]] = or i32 [[A_VAL]], 1
+ // CHECK: store i32 [[OR]], i32* [[A]], align
+ // CHECK: [[BV16:%.+]] = load i16, i16* [[B]], align
+ // CHECK: [[BV:%.+]] = sext i16 [[BV16]] to i32
+ // CHECK: [[CMP:%.+]] = icmp sgt i32 99, [[BV]]
+ // CHECK: br i1 [[CMP]], label {{%?}}[[DO_MAX:.+]], label {{%?}}[[MAX_ELSE:.+]]
+ //
+ // CHECK: [[DO_MAX]]
+ // CHECK: br label {{%?}}[[MAX_CONT:.+]]
+ //
+ // CHECK: [[MAX_ELSE]]
+ // CHECK: [[BV:%.+]] = load i16, i16* [[B]], align
+ // CHECK: [[MAX:%.+]] = sext i16 [[BV]] to i32
+ // CHECK: br label {{%?}}[[MAX_CONT]]
+ //
+ // CHECK: [[MAX_CONT]]
+ // CHECK: [[B_LVALUE:%.+]] = phi i32 [ 99, %[[DO_MAX]] ], [ [[MAX]], %[[MAX_ELSE]] ]
+ // CHECK: [[TRUNC:%.+]] = trunc i32 [[B_LVALUE]] to i16
+ // CHECK: store i16 [[TRUNC]], i16* [[B]], align
+ // CHECK: [[PTR1:%.+]] = getelementptr inbounds [[RLT:.+]], [2 x i8*]* [[RL:%.+]], i{{32|64}} 0, i{{32|64}} 0
+ // CHECK: [[A_CAST:%.+]] = bitcast i32* [[A]] to i8*
+ // CHECK: store i8* [[A_CAST]], i8** [[PTR1]], align
+ // CHECK: [[PTR2:%.+]] = getelementptr inbounds [[RLT]], [[RLT]]* [[RL]], i{{32|64}} 0, i{{32|64}} 1
+ // CHECK: [[B_CAST:%.+]] = bitcast i16* [[B]] to i8*
+ // CHECK: store i8* [[B_CAST]], i8** [[PTR2]], align
+ // CHECK: [[ARG_RL:%.+]] = bitcast [[RLT]]* [[RL]] to i8*
+ // CHECK: [[RET:%.+]] = call i32 @__kmpc_nvptx_parallel_reduce_nowait(i32 {{.+}}, i32 2, i{{32|64}} {{8|16}}, i8* [[ARG_RL]], void (i8*, i16, i16, i16)* [[SHUFFLE_REDUCE_FN:@.+]], void (i8*, i32)* [[WARP_COPY_FN:@.+]])
+ // CHECK: switch i32 [[RET]], label {{%?}}[[DEFAULTLABEL:.+]] [
+ // CHECK: i32 1, label {{%?}}[[REDLABEL:.+]]
+
+ // CHECK: [[REDLABEL]]
+ // CHECK: [[A_INV:%.+]] = load i32, i32* [[A_IN:%.+]], align
+ // CHECK: [[AV:%.+]] = load i32, i32* [[A]], align
+ // CHECK: [[OR:%.+]] = or i32 [[A_INV]], [[AV]]
+ // CHECK: store i32 [[OR]], i32* [[A_IN]], align
+ // CHECK: [[B_INV16:%.+]] = load i16, i16* [[B_IN:%.+]], align
+ // CHECK: [[B_INV:%.+]] = sext i16 [[B_INV16]] to i32
+ // CHECK: [[BV16:%.+]] = load i16, i16* [[B]], align
+ // CHECK: [[BV:%.+]] = sext i16 [[BV16]] to i32
+ // CHECK: [[CMP:%.+]] = icmp sgt i32 [[B_INV]], [[BV]]
+ // CHECK: br i1 [[CMP]], label {{%?}}[[DO_MAX:.+]], label {{%?}}[[MAX_ELSE:.+]]
+ //
+ // CHECK: [[DO_MAX]]
+ // CHECK: [[MAX1:%.+]] = load i16, i16* [[B_IN]], align
+ // CHECK: br label {{%?}}[[MAX_CONT:.+]]
+ //
+ // CHECK: [[MAX_ELSE]]
+ // CHECK: [[MAX2:%.+]] = load i16, i16* [[B]], align
+ // CHECK: br label {{%?}}[[MAX_CONT]]
+ //
+ // CHECK: [[MAX_CONT]]
+ // CHECK: [[B_MAX:%.+]] = phi i16 [ [[MAX1]], %[[DO_MAX]] ], [ [[MAX2]], %[[MAX_ELSE]] ]
+ // CHECK: store i16 [[B_MAX]], i16* [[B_IN]], align
+ // CHECK: call void @__kmpc_nvptx_end_reduce_nowait(
+ // CHECK: br label %[[DEFAULTLABEL]]
+ //
+ // CHECK: [[DEFAULTLABEL]]
+ // CHECK: ret
+
+ //
+ // Reduction function
+ // CHECK: define internal void [[REDUCTION_FUNC:@.+]](i8*, i8*)
+ // CHECK: [[VAR1_RHS_REF:%.+]] = getelementptr inbounds [[RLT]], [[RLT]]* [[RED_LIST_RHS:%.+]], i{{32|64}} 0, i{{32|64}} 0
+ // CHECK: [[VAR1_RHS_VOID:%.+]] = load i8*, i8** [[VAR1_RHS_REF]],
+ // CHECK: [[VAR1_RHS:%.+]] = bitcast i8* [[VAR1_RHS_VOID]] to i32*
+ //
+ // CHECK: [[VAR1_LHS_REF:%.+]] = getelementptr inbounds [[RLT]], [[RLT]]* [[RED_LIST_LHS:%.+]], i{{32|64}} 0, i{{32|64}} 0
+ // CHECK: [[VAR1_LHS_VOID:%.+]] = load i8*, i8** [[VAR1_LHS_REF]],
+ // CHECK: [[VAR1_LHS:%.+]] = bitcast i8* [[VAR1_LHS_VOID]] to i32*
+ //
+ // CHECK: [[VAR2_RHS_REF:%.+]] = getelementptr inbounds [[RLT]], [[RLT]]* [[RED_LIST_RHS]], i{{32|64}} 0, i{{32|64}} 1
+ // CHECK: [[VAR2_RHS_VOID:%.+]] = load i8*, i8** [[VAR2_RHS_REF]],
+ // CHECK: [[VAR2_RHS:%.+]] = bitcast i8* [[VAR2_RHS_VOID]] to i16*
+ //
+ // CHECK: [[VAR2_LHS_REF:%.+]] = getelementptr inbounds [[RLT]], [[RLT]]* [[RED_LIST_LHS]], i{{32|64}} 0, i{{32|64}} 1
+ // CHECK: [[VAR2_LHS_VOID:%.+]] = load i8*, i8** [[VAR2_LHS_REF]],
+ // CHECK: [[VAR2_LHS:%.+]] = bitcast i8* [[VAR2_LHS_VOID]] to i16*
+ //
+ // CHECK: [[VAR1_LHS_VAL:%.+]] = load i32, i32* [[VAR1_LHS]],
+ // CHECK: [[VAR1_RHS_VAL:%.+]] = load i32, i32* [[VAR1_RHS]],
+ // CHECK: [[OR:%.+]] = or i32 [[VAR1_LHS_VAL]], [[VAR1_RHS_VAL]]
+ // CHECK: store i32 [[OR]], i32* [[VAR1_LHS]],
+ //
+ // CHECK: [[VAR2_LHS_VAL16:%.+]] = load i16, i16* [[VAR2_LHS]],
+ // CHECK: [[VAR2_LHS_VAL:%.+]] = sext i16 [[VAR2_LHS_VAL16]] to i32
+ // CHECK: [[VAR2_RHS_VAL16:%.+]] = load i16, i16* [[VAR2_RHS]],
+ // CHECK: [[VAR2_RHS_VAL:%.+]] = sext i16 [[VAR2_RHS_VAL16]] to i32
+ //
+ // CHECK: [[CMP:%.+]] = icmp sgt i32 [[VAR2_LHS_VAL]], [[VAR2_RHS_VAL]]
+ // CHECK: br i1 [[CMP]], label {{%?}}[[DO_MAX:.+]], label {{%?}}[[MAX_ELSE:.+]]
+ //
+ // CHECK: [[DO_MAX]]
+ // CHECK: [[MAX1:%.+]] = load i16, i16* [[VAR2_LHS]], align
+ // CHECK: br label {{%?}}[[MAX_CONT:.+]]
+ //
+ // CHECK: [[MAX_ELSE]]
+ // CHECK: [[MAX2:%.+]] = load i16, i16* [[VAR2_RHS]], align
+ // CHECK: br label {{%?}}[[MAX_CONT]]
+ //
+ // CHECK: [[MAX_CONT]]
+ // CHECK: [[MAXV:%.+]] = phi i16 [ [[MAX1]], %[[DO_MAX]] ], [ [[MAX2]], %[[MAX_ELSE]] ]
+ // CHECK: store i16 [[MAXV]], i16* [[VAR2_LHS]],
+ // CHECK: ret void
+
+ //
+ // Shuffle and reduce function
+ // CHECK: define internal void [[SHUFFLE_REDUCE_FN]](i8*, i16 {{.*}}, i16 {{.*}}, i16 {{.*}})
+ // CHECK: [[REMOTE_RED_LIST:%.+]] = alloca [[RLT]], align
+ // CHECK: [[REMOTE_ELT1:%.+]] = alloca i32
+ // CHECK: [[REMOTE_ELT2:%.+]] = alloca i16
+ //
+ // CHECK: [[LANEID:%.+]] = load i16, i16* {{.+}}, align
+ // CHECK: [[LANEOFFSET:%.+]] = load i16, i16* {{.+}}, align
+ // CHECK: [[ALGVER:%.+]] = load i16, i16* {{.+}}, align
+ //
+ // CHECK: [[ELT_REF:%.+]] = getelementptr inbounds [[RLT]], [[RLT]]* [[RED_LIST:%.+]], i{{32|64}} 0, i{{32|64}} 0
+ // CHECK: [[ELT_VOID:%.+]] = load i8*, i8** [[ELT_REF]],
+ // CHECK: [[REMOTE_ELT_REF:%.+]] = getelementptr inbounds [[RLT]], [[RLT]]* [[REMOTE_RED_LIST:%.+]], i{{32|64}} 0, i{{32|64}} 0
+ // CHECK: [[ELT:%.+]] = bitcast i8* [[ELT_VOID]] to i32*
+ // CHECK: [[ELT_VAL:%.+]] = load i32, i32* [[ELT]], align
+ //
+ // CHECK: [[WS32:%.+]] = call i32 @llvm.nvvm.read.ptx.sreg.warpsize()
+ // CHECK: [[WS:%.+]] = trunc i32 [[WS32]] to i16
+ // CHECK: [[REMOTE_ELT1_VAL:%.+]] = call i32 @__kmpc_shuffle_int32(i32 [[ELT_VAL]], i16 [[LANEOFFSET]], i16 [[WS]])
+ //
+ // CHECK: store i32 [[REMOTE_ELT1_VAL]], i32* [[REMOTE_ELT1]], align
+ // CHECK: [[REMOTE_ELT1C:%.+]] = bitcast i32* [[REMOTE_ELT1]] to i8*
+ // CHECK: store i8* [[REMOTE_ELT1C]], i8** [[REMOTE_ELT_REF]], align
+ //
+ // CHECK: [[ELT_REF:%.+]] = getelementptr inbounds [[RLT]], [[RLT]]* [[RED_LIST]], i{{32|64}} 0, i{{32|64}} 1
+ // CHECK: [[ELT_VOID:%.+]] = load i8*, i8** [[ELT_REF]],
+ // CHECK: [[REMOTE_ELT_REF:%.+]] = getelementptr inbounds [[RLT]], [[RLT]]* [[REMOTE_RED_LIST]], i{{32|64}} 0, i{{32|64}} 1
+ // CHECK: [[ELT:%.+]] = bitcast i8* [[ELT_VOID]] to i16*
+ // CHECK: [[ELT_VAL:%.+]] = load i16, i16* [[ELT]], align
+ //
+ // CHECK: [[ELT_CAST:%.+]] = sext i16 [[ELT_VAL]] to i32
+ // CHECK: [[WS32:%.+]] = call i32 @llvm.nvvm.read.ptx.sreg.warpsize()
+ // CHECK: [[WS:%.+]] = trunc i32 [[WS32]] to i16
+ // CHECK: [[REMOTE_ELT2_VAL32:%.+]] = call i32 @__kmpc_shuffle_int32(i32 [[ELT_CAST]], i16 [[LANEOFFSET]], i16 [[WS]])
+ // CHECK: [[REMOTE_ELT2_VAL:%.+]] = trunc i32 [[REMOTE_ELT2_VAL32]] to i16
+ //
+ // CHECK: store i16 [[REMOTE_ELT2_VAL]], i16* [[REMOTE_ELT2]], align
+ // CHECK: [[REMOTE_ELT2C:%.+]] = bitcast i16* [[REMOTE_ELT2]] to i8*
+ // CHECK: store i8* [[REMOTE_ELT2C]], i8** [[REMOTE_ELT_REF]], align
+ //
+ // Condition to reduce
+ // CHECK: [[CONDALG0:%.+]] = icmp eq i16 [[ALGVER]], 0
+ //
+ // CHECK: [[COND1:%.+]] = icmp eq i16 [[ALGVER]], 1
+ // CHECK: [[COND2:%.+]] = icmp ult i16 [[LANEID]], [[LANEOFFSET]]
+ // CHECK: [[CONDALG1:%.+]] = and i1 [[COND1]], [[COND2]]
+ //
+ // CHECK: [[COND3:%.+]] = icmp eq i16 [[ALGVER]], 2
+ // CHECK: [[COND4:%.+]] = and i16 [[LANEID]], 1
+ // CHECK: [[COND5:%.+]] = icmp eq i16 [[COND4]], 0
+ // CHECK: [[COND6:%.+]] = and i1 [[COND3]], [[COND5]]
+ // CHECK: [[COND7:%.+]] = icmp sgt i16 [[LANEOFFSET]], 0
+ // CHECK: [[CONDALG2:%.+]] = and i1 [[COND6]], [[COND7]]
+ //
+ // CHECK: [[COND8:%.+]] = or i1 [[CONDALG0]], [[CONDALG1]]
+ // CHECK: [[SHOULD_REDUCE:%.+]] = or i1 [[COND8]], [[CONDALG2]]
+ // CHECK: br i1 [[SHOULD_REDUCE]], label {{%?}}[[DO_REDUCE:.+]], label {{%?}}[[REDUCE_ELSE:.+]]
+ //
+ // CHECK: [[DO_REDUCE]]
+ // CHECK: [[RED_LIST1_VOID:%.+]] = bitcast [[RLT]]* [[RED_LIST]] to i8*
+ // CHECK: [[RED_LIST2_VOID:%.+]] = bitcast [[RLT]]* [[REMOTE_RED_LIST]] to i8*
+ // CHECK: call void [[REDUCTION_FUNC]](i8* [[RED_LIST1_VOID]], i8* [[RED_LIST2_VOID]])
+ // CHECK: br label {{%?}}[[REDUCE_CONT:.+]]
+ //
+ // CHECK: [[REDUCE_ELSE]]
+ // CHECK: br label {{%?}}[[REDUCE_CONT]]
+ //
+ // CHECK: [[REDUCE_CONT]]
+ // Now check if we should just copy over the remote reduction list
+ // CHECK: [[COND1:%.+]] = icmp eq i16 [[ALGVER]], 1
+ // CHECK: [[COND2:%.+]] = icmp uge i16 [[LANEID]], [[LANEOFFSET]]
+ // CHECK: [[SHOULD_COPY:%.+]] = and i1 [[COND1]], [[COND2]]
+ // CHECK: br i1 [[SHOULD_COPY]], label {{%?}}[[DO_COPY:.+]], label {{%?}}[[COPY_ELSE:.+]]
+ //
+ // CHECK: [[DO_COPY]]
+ // CHECK: [[REMOTE_ELT_REF:%.+]] = getelementptr inbounds [[RLT]], [[RLT]]* [[REMOTE_RED_LIST]], i{{32|64}} 0, i{{32|64}} 0
+ // CHECK: [[REMOTE_ELT_VOID:%.+]] = load i8*, i8** [[REMOTE_ELT_REF]],
+ // CHECK: [[ELT_REF:%.+]] = getelementptr inbounds [[RLT]], [[RLT]]* [[RED_LIST]], i{{32|64}} 0, i{{32|64}} 0
+ // CHECK: [[ELT_VOID:%.+]] = load i8*, i8** [[ELT_REF]],
+ // CHECK: [[ELT:%.+]] = bitcast i8* [[ELT_VOID]] to i32*
+ // CHECK: [[REMOTE_ELT:%.+]] = bitcast i8* [[REMOTE_ELT_VOID]] to i32*
+ // CHECK: [[REMOTE_ELT_VAL:%.+]] = load i32, i32* [[REMOTE_ELT]], align
+ // CHECK: store i32 [[REMOTE_ELT_VAL]], i32* [[ELT]], align
+ //
+ // CHECK: [[REMOTE_ELT_REF:%.+]] = getelementptr inbounds [[RLT]], [[RLT]]* [[REMOTE_RED_LIST]], i{{32|64}} 0, i{{32|64}} 1
+ // CHECK: [[REMOTE_ELT_VOID:%.+]] = load i8*, i8** [[REMOTE_ELT_REF]],
+ // CHECK: [[ELT_REF:%.+]] = getelementptr inbounds [[RLT]], [[RLT]]* [[RED_LIST]], i{{32|64}} 0, i{{32|64}} 1
+ // CHECK: [[ELT_VOID:%.+]] = load i8*, i8** [[ELT_REF]],
+ // CHECK: [[ELT:%.+]] = bitcast i8* [[ELT_VOID]] to i16*
+ // CHECK: [[REMOTE_ELT:%.+]] = bitcast i8* [[REMOTE_ELT_VOID]] to i16*
+ // CHECK: [[REMOTE_ELT_VAL:%.+]] = load i16, i16* [[REMOTE_ELT]], align
+ // CHECK: store i16 [[REMOTE_ELT_VAL]], i16* [[ELT]], align
+ // CHECK: br label {{%?}}[[COPY_CONT:.+]]
+ //
+ // CHECK: [[COPY_ELSE]]
+ // CHECK: br label {{%?}}[[COPY_CONT]]
+ //
+ // CHECK: [[COPY_CONT]]
+ // CHECK: void
+
+ //
+ // Inter warp copy function
+ // CHECK: define internal void [[WARP_COPY_FN]](i8*, i32)
+ // CHECK-DAG: [[LANEID:%.+]] = and i32 {{.+}}, 31
+ // CHECK-DAG: [[WARPID:%.+]] = ashr i32 {{.+}}, 5
+ // CHECK-DAG: [[RED_LIST:%.+]] = bitcast i8* {{.+}} to [[RLT]]*
+ // CHECK: [[IS_WARP_MASTER:%.+]] = icmp eq i32 [[LANEID]], 0
+ // CHECK: br i1 [[IS_WARP_MASTER]], label {{%?}}[[DO_COPY:.+]], label {{%?}}[[COPY_ELSE:.+]]
+ //
+ // [[DO_COPY]]
+ // CHECK: [[ELT_REF:%.+]] = getelementptr inbounds [[RLT]], [[RLT]]* [[RED_LIST]], i{{32|64}} 0, i{{32|64}} 0
+ // CHECK: [[ELT_VOID:%.+]] = load i8*, i8** [[ELT_REF]],
+ // CHECK: [[ELT:%.+]] = bitcast i8* [[ELT_VOID]] to i32*
+ // CHECK: [[ELT_VAL:%.+]] = load i32, i32* [[ELT]], align
+ //
+ // CHECK: [[MEDIUM_ELT64:%.+]] = getelementptr inbounds [32 x i64], [32 x i64] addrspace([[SHARED_ADDRSPACE]])* [[TRANSFER_STORAGE]], i64 0, i32 [[WARPID]]
+ // CHECK: [[MEDIUM_ELT:%.+]] = bitcast i64 addrspace([[SHARED_ADDRSPACE]])* [[MEDIUM_ELT64]] to i32 addrspace([[SHARED_ADDRSPACE]])*
+ // CHECK: store i32 [[ELT_VAL]], i32 addrspace([[SHARED_ADDRSPACE]])* [[MEDIUM_ELT]], align
+ // CHECK: br label {{%?}}[[COPY_CONT:.+]]
+ //
+ // CHECK: [[COPY_ELSE]]
+ // CHECK: br label {{%?}}[[COPY_CONT]]
+ //
+ // Barrier after copy to shared memory storage medium.
+ // CHECK: [[COPY_CONT]]
+ // CHECK: [[WS:%.+]] = call i32 @llvm.nvvm.read.ptx.sreg.warpsize()
+ // CHECK: [[ACTIVE_THREADS:%.+]] = mul nsw i32 [[ACTIVE_WARPS:%.+]], [[WS]]
+ // CHECK: call void @llvm.nvvm.barrier(i32 1, i32 [[ACTIVE_THREADS]])
+ //
+ // Read into warp 0.
+ // CHECK: [[IS_W0_ACTIVE_THREAD:%.+]] = icmp ult i32 [[TID:%.+]], [[ACTIVE_WARPS]]
+ // CHECK: br i1 [[IS_W0_ACTIVE_THREAD]], label {{%?}}[[DO_READ:.+]], label {{%?}}[[READ_ELSE:.+]]
+ //
+ // CHECK: [[DO_READ]]
+ // CHECK: [[MEDIUM_ELT64:%.+]] = getelementptr inbounds [32 x i64], [32 x i64] addrspace([[SHARED_ADDRSPACE]])* [[TRANSFER_STORAGE]], i64 0, i32 [[TID]]
+ // CHECK: [[MEDIUM_ELT:%.+]] = bitcast i64 addrspace([[SHARED_ADDRSPACE]])* [[MEDIUM_ELT64]] to i32 addrspace([[SHARED_ADDRSPACE]])*
+ // CHECK: [[MEDIUM_ELT_VAL:%.+]] = load i32, i32 addrspace([[SHARED_ADDRSPACE]])* [[MEDIUM_ELT]], align
+ // CHECK: [[ELT_REF:%.+]] = getelementptr inbounds [[RLT]], [[RLT]]* [[RED_LIST:%.+]], i{{32|64}} 0, i{{32|64}} 0
+ // CHECK: [[ELT_VOID:%.+]] = load i8*, i8** [[ELT_REF]],
+ // CHECK: [[ELT:%.+]] = bitcast i8* [[ELT_VOID]] to i32*
+ // CHECK: store i32 [[MEDIUM_ELT_VAL]], i32* [[ELT]], align
+ // CHECK: br label {{%?}}[[READ_CONT:.+]]
+ //
+ // CHECK: [[READ_ELSE]]
+ // CHECK: br label {{%?}}[[READ_CONT]]
+ //
+ // CHECK: [[READ_CONT]]
+ // CHECK: call void @llvm.nvvm.barrier(i32 1, i32 [[ACTIVE_THREADS]])
+ // CHECK: [[IS_WARP_MASTER:%.+]] = icmp eq i32 [[LANEID]], 0
+ // CHECK: br i1 [[IS_WARP_MASTER]], label {{%?}}[[DO_COPY:.+]], label {{%?}}[[COPY_ELSE:.+]]
+ //
+ // [[DO_COPY]]
+ // CHECK: [[ELT_REF:%.+]] = getelementptr inbounds [[RLT]], [[RLT]]* [[RED_LIST]], i{{32|64}} 0, i{{32|64}} 1
+ // CHECK: [[ELT_VOID:%.+]] = load i8*, i8** [[ELT_REF]],
+ // CHECK: [[ELT:%.+]] = bitcast i8* [[ELT_VOID]] to i16*
+ // CHECK: [[ELT_VAL:%.+]] = load i16, i16* [[ELT]], align
+ //
+ // CHECK: [[MEDIUM_ELT64:%.+]] = getelementptr inbounds [32 x i64], [32 x i64] addrspace([[SHARED_ADDRSPACE]])* [[TRANSFER_STORAGE]], i64 0, i32 [[WARPID]]
+ // CHECK: [[MEDIUM_ELT:%.+]] = bitcast i64 addrspace([[SHARED_ADDRSPACE]])* [[MEDIUM_ELT64]] to i16 addrspace([[SHARED_ADDRSPACE]])*
+ // CHECK: store i16 [[ELT_VAL]], i16 addrspace([[SHARED_ADDRSPACE]])* [[MEDIUM_ELT]], align
+ // CHECK: br label {{%?}}[[COPY_CONT:.+]]
+ //
+ // CHECK: [[COPY_ELSE]]
+ // CHECK: br label {{%?}}[[COPY_CONT]]
+ //
+ // Barrier after copy to shared memory storage medium.
+ // CHECK: [[COPY_CONT]]
+ // CHECK: [[WS:%.+]] = call i32 @llvm.nvvm.read.ptx.sreg.warpsize()
+ // CHECK: [[ACTIVE_THREADS:%.+]] = mul nsw i32 [[ACTIVE_WARPS:%.+]], [[WS]]
+ // CHECK: call void @llvm.nvvm.barrier(i32 1, i32 [[ACTIVE_THREADS]])
+ //
+ // Read into warp 0.
+ // CHECK: [[IS_W0_ACTIVE_THREAD:%.+]] = icmp ult i32 [[TID:%.+]], [[ACTIVE_WARPS]]
+ // CHECK: br i1 [[IS_W0_ACTIVE_THREAD]], label {{%?}}[[DO_READ:.+]], label {{%?}}[[READ_ELSE:.+]]
+ //
+ // CHECK: [[DO_READ]]
+ // CHECK: [[MEDIUM_ELT64:%.+]] = getelementptr inbounds [32 x i64], [32 x i64] addrspace([[SHARED_ADDRSPACE]])* [[TRANSFER_STORAGE]], i64 0, i32 [[TID]]
+ // CHECK: [[MEDIUM_ELT:%.+]] = bitcast i64 addrspace([[SHARED_ADDRSPACE]])* [[MEDIUM_ELT64]] to i16 addrspace([[SHARED_ADDRSPACE]])*
+ // CHECK: [[MEDIUM_ELT_VAL:%.+]] = load i16, i16 addrspace([[SHARED_ADDRSPACE]])* [[MEDIUM_ELT]], align
+ // CHECK: [[ELT_REF:%.+]] = getelementptr inbounds [[RLT]], [[RLT]]* [[RED_LIST:%.+]], i{{32|64}} 0, i{{32|64}} 1
+ // CHECK: [[ELT_VOID:%.+]] = load i8*, i8** [[ELT_REF]],
+ // CHECK: [[ELT:%.+]] = bitcast i8* [[ELT_VOID]] to i16*
+ // CHECK: store i16 [[MEDIUM_ELT_VAL]], i16* [[ELT]], align
+ // CHECK: br label {{%?}}[[READ_CONT:.+]]
+ //
+ // CHECK: [[READ_ELSE]]
+ // CHECK: br label {{%?}}[[READ_CONT]]
+ //
+ // CHECK: [[READ_CONT]]
+ // CHECK: call void @llvm.nvvm.barrier(i32 1, i32 [[ACTIVE_THREADS]])
+ // CHECK: ret
+
+#endif