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llvm-for-llvmta/include/llvm/Frontend/OpenMP/OMPIRBuilder.h

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//===- IR/OpenMPIRBuilder.h - OpenMP encoding builder for LLVM IR - C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file defines the OpenMPIRBuilder class and helpers used as a convenient
// way to create LLVM instructions for OpenMP directives.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_OPENMP_IR_IRBUILDER_H
#define LLVM_OPENMP_IR_IRBUILDER_H
#include "llvm/Frontend/OpenMP/OMPConstants.h"
#include "llvm/IR/DebugLoc.h"
#include "llvm/IR/IRBuilder.h"
#include "llvm/Support/Allocator.h"
#include <forward_list>
namespace llvm {
class CanonicalLoopInfo;
/// An interface to create LLVM-IR for OpenMP directives.
///
/// Each OpenMP directive has a corresponding public generator method.
class OpenMPIRBuilder {
public:
/// Create a new OpenMPIRBuilder operating on the given module \p M. This will
/// not have an effect on \p M (see initialize).
OpenMPIRBuilder(Module &M) : M(M), Builder(M.getContext()) {}
/// Initialize the internal state, this will put structures types and
/// potentially other helpers into the underlying module. Must be called
/// before any other method and only once!
void initialize();
/// Finalize the underlying module, e.g., by outlining regions.
/// \param AllowExtractorSinking Flag to include sinking instructions,
/// emitted by CodeExtractor, in the
/// outlined region. Default is false.
void finalize(bool AllowExtractorSinking = false);
/// Add attributes known for \p FnID to \p Fn.
void addAttributes(omp::RuntimeFunction FnID, Function &Fn);
/// Type used throughout for insertion points.
using InsertPointTy = IRBuilder<>::InsertPoint;
/// Callback type for variable finalization (think destructors).
///
/// \param CodeGenIP is the insertion point at which the finalization code
/// should be placed.
///
/// A finalize callback knows about all objects that need finalization, e.g.
/// destruction, when the scope of the currently generated construct is left
/// at the time, and location, the callback is invoked.
using FinalizeCallbackTy = std::function<void(InsertPointTy CodeGenIP)>;
struct FinalizationInfo {
/// The finalization callback provided by the last in-flight invocation of
/// createXXXX for the directive of kind DK.
FinalizeCallbackTy FiniCB;
/// The directive kind of the innermost directive that has an associated
/// region which might require finalization when it is left.
omp::Directive DK;
/// Flag to indicate if the directive is cancellable.
bool IsCancellable;
};
/// Push a finalization callback on the finalization stack.
///
/// NOTE: Temporary solution until Clang CG is gone.
void pushFinalizationCB(const FinalizationInfo &FI) {
FinalizationStack.push_back(FI);
}
/// Pop the last finalization callback from the finalization stack.
///
/// NOTE: Temporary solution until Clang CG is gone.
void popFinalizationCB() { FinalizationStack.pop_back(); }
/// Callback type for body (=inner region) code generation
///
/// The callback takes code locations as arguments, each describing a
/// location at which code might need to be generated or a location that is
/// the target of control transfer.
///
/// \param AllocaIP is the insertion point at which new alloca instructions
/// should be placed.
/// \param CodeGenIP is the insertion point at which the body code should be
/// placed.
/// \param ContinuationBB is the basic block target to leave the body.
///
/// Note that all blocks pointed to by the arguments have terminators.
using BodyGenCallbackTy =
function_ref<void(InsertPointTy AllocaIP, InsertPointTy CodeGenIP,
BasicBlock &ContinuationBB)>;
/// Callback type for loop body code generation.
///
/// \param CodeGenIP is the insertion point where the loop's body code must be
/// placed. This will be a dedicated BasicBlock with a
/// conditional branch from the loop condition check and
/// terminated with an unconditional branch to the loop
/// latch.
/// \param IndVar is the induction variable usable at the insertion point.
using LoopBodyGenCallbackTy =
function_ref<void(InsertPointTy CodeGenIP, Value *IndVar)>;
/// Callback type for variable privatization (think copy & default
/// constructor).
///
/// \param AllocaIP is the insertion point at which new alloca instructions
/// should be placed.
/// \param CodeGenIP is the insertion point at which the privatization code
/// should be placed.
/// \param Original The value being copied/created, should not be used in the
/// generated IR.
/// \param Inner The equivalent of \p Original that should be used in the
/// generated IR; this is equal to \p Original if the value is
/// a pointer and can thus be passed directly, otherwise it is
/// an equivalent but different value.
/// \param ReplVal The replacement value, thus a copy or new created version
/// of \p Inner.
///
/// \returns The new insertion point where code generation continues and
/// \p ReplVal the replacement value.
using PrivatizeCallbackTy = function_ref<InsertPointTy(
InsertPointTy AllocaIP, InsertPointTy CodeGenIP, Value &Original,
Value &Inner, Value *&ReplVal)>;
/// Description of a LLVM-IR insertion point (IP) and a debug/source location
/// (filename, line, column, ...).
struct LocationDescription {
template <typename T, typename U>
LocationDescription(const IRBuilder<T, U> &IRB)
: IP(IRB.saveIP()), DL(IRB.getCurrentDebugLocation()) {}
LocationDescription(const InsertPointTy &IP) : IP(IP) {}
LocationDescription(const InsertPointTy &IP, const DebugLoc &DL)
: IP(IP), DL(DL) {}
InsertPointTy IP;
DebugLoc DL;
};
/// Emitter methods for OpenMP directives.
///
///{
/// Generator for '#omp barrier'
///
/// \param Loc The location where the barrier directive was encountered.
/// \param DK The kind of directive that caused the barrier.
/// \param ForceSimpleCall Flag to force a simple (=non-cancellation) barrier.
/// \param CheckCancelFlag Flag to indicate a cancel barrier return value
/// should be checked and acted upon.
///
/// \returns The insertion point after the barrier.
InsertPointTy createBarrier(const LocationDescription &Loc, omp::Directive DK,
bool ForceSimpleCall = false,
bool CheckCancelFlag = true);
/// Generator for '#omp cancel'
///
/// \param Loc The location where the directive was encountered.
/// \param IfCondition The evaluated 'if' clause expression, if any.
/// \param CanceledDirective The kind of directive that is cancled.
///
/// \returns The insertion point after the barrier.
InsertPointTy createCancel(const LocationDescription &Loc, Value *IfCondition,
omp::Directive CanceledDirective);
/// Generator for '#omp parallel'
///
/// \param Loc The insert and source location description.
/// \param AllocaIP The insertion points to be used for alloca instructions.
/// \param BodyGenCB Callback that will generate the region code.
/// \param PrivCB Callback to copy a given variable (think copy constructor).
/// \param FiniCB Callback to finalize variable copies.
/// \param IfCondition The evaluated 'if' clause expression, if any.
/// \param NumThreads The evaluated 'num_threads' clause expression, if any.
/// \param ProcBind The value of the 'proc_bind' clause (see ProcBindKind).
/// \param IsCancellable Flag to indicate a cancellable parallel region.
///
/// \returns The insertion position *after* the parallel.
IRBuilder<>::InsertPoint
createParallel(const LocationDescription &Loc, InsertPointTy AllocaIP,
BodyGenCallbackTy BodyGenCB, PrivatizeCallbackTy PrivCB,
FinalizeCallbackTy FiniCB, Value *IfCondition,
Value *NumThreads, omp::ProcBindKind ProcBind,
bool IsCancellable);
/// Generator for the control flow structure of an OpenMP canonical loop.
///
/// This generator operates on the logical iteration space of the loop, i.e.
/// the caller only has to provide a loop trip count of the loop as defined by
/// base language semantics. The trip count is interpreted as an unsigned
/// integer. The induction variable passed to \p BodyGenCB will be of the same
/// type and run from 0 to \p TripCount - 1. It is up to the callback to
/// convert the logical iteration variable to the loop counter variable in the
/// loop body.
///
/// \param Loc The insert and source location description. The insert
/// location can be between two instructions or the end of a
/// degenerate block (e.g. a BB under construction).
/// \param BodyGenCB Callback that will generate the loop body code.
/// \param TripCount Number of iterations the loop body is executed.
/// \param Name Base name used to derive BB and instruction names.
///
/// \returns An object representing the created control flow structure which
/// can be used for loop-associated directives.
CanonicalLoopInfo *createCanonicalLoop(const LocationDescription &Loc,
LoopBodyGenCallbackTy BodyGenCB,
Value *TripCount,
const Twine &Name = "loop");
/// Generator for the control flow structure of an OpenMP canonical loop.
///
/// Instead of a logical iteration space, this allows specifying user-defined
/// loop counter values using increment, upper- and lower bounds. To
/// disambiguate the terminology when counting downwards, instead of lower
/// bounds we use \p Start for the loop counter value in the first body
/// iteration.
///
/// Consider the following limitations:
///
/// * A loop counter space over all integer values of its bit-width cannot be
/// represented. E.g using uint8_t, its loop trip count of 256 cannot be
/// stored into an 8 bit integer):
///
/// DO I = 0, 255, 1
///
/// * Unsigned wrapping is only supported when wrapping only "once"; E.g.
/// effectively counting downwards:
///
/// for (uint8_t i = 100u; i > 0; i += 127u)
///
///
/// TODO: May need to add additional parameters to represent:
///
/// * Allow representing downcounting with unsigned integers.
///
/// * Sign of the step and the comparison operator might disagree:
///
/// for (int i = 0; i < 42; --i)
///
//
/// \param Loc The insert and source location description.
/// \param BodyGenCB Callback that will generate the loop body code.
/// \param Start Value of the loop counter for the first iterations.
/// \param Stop Loop counter values past this will stop the the
/// iterations.
/// \param Step Loop counter increment after each iteration; negative
/// means counting down. \param IsSigned Whether Start, Stop
/// and Stop are signed integers.
/// \param InclusiveStop Whether \p Stop itself is a valid value for the loop
/// counter.
/// \param ComputeIP Insertion point for instructions computing the trip
/// count. Can be used to ensure the trip count is available
/// at the outermost loop of a loop nest. If not set,
/// defaults to the preheader of the generated loop.
/// \param Name Base name used to derive BB and instruction names.
///
/// \returns An object representing the created control flow structure which
/// can be used for loop-associated directives.
CanonicalLoopInfo *createCanonicalLoop(const LocationDescription &Loc,
LoopBodyGenCallbackTy BodyGenCB,
Value *Start, Value *Stop, Value *Step,
bool IsSigned, bool InclusiveStop,
InsertPointTy ComputeIP = {},
const Twine &Name = "loop");
/// Modifies the canonical loop to be a statically-scheduled workshare loop.
///
/// This takes a \p LoopInfo representing a canonical loop, such as the one
/// created by \p createCanonicalLoop and emits additional instructions to
/// turn it into a workshare loop. In particular, it calls to an OpenMP
/// runtime function in the preheader to obtain the loop bounds to be used in
/// the current thread, updates the relevant instructions in the canonical
/// loop and calls to an OpenMP runtime finalization function after the loop.
///
/// \param Loc The source location description, the insertion location
/// is not used.
/// \param CLI A descriptor of the canonical loop to workshare.
/// \param AllocaIP An insertion point for Alloca instructions usable in the
/// preheader of the loop.
/// \param NeedsBarrier Indicates whether a barrier must be insterted after
/// the loop.
/// \param Chunk The size of loop chunk considered as a unit when
/// scheduling. If \p nullptr, defaults to 1.
///
/// \returns Updated CanonicalLoopInfo.
CanonicalLoopInfo *createStaticWorkshareLoop(const LocationDescription &Loc,
CanonicalLoopInfo *CLI,
InsertPointTy AllocaIP,
bool NeedsBarrier,
Value *Chunk = nullptr);
/// Tile a loop nest.
///
/// Tiles the loops of \p Loops by the tile sizes in \p TileSizes. Loops in
/// \p/ Loops must be perfectly nested, from outermost to innermost loop
/// (i.e. Loops.front() is the outermost loop). The trip count llvm::Value
/// of every loop and every tile sizes must be usable in the outermost
/// loop's preheader. This implies that the loop nest is rectangular.
///
/// Example:
/// \code
/// for (int i = 0; i < 15; ++i) // Canonical loop "i"
/// for (int j = 0; j < 14; ++j) // Canonical loop "j"
/// body(i, j);
/// \endcode
///
/// After tiling with Loops={i,j} and TileSizes={5,7}, the loop is changed to
/// \code
/// for (int i1 = 0; i1 < 3; ++i1)
/// for (int j1 = 0; j1 < 2; ++j1)
/// for (int i2 = 0; i2 < 5; ++i2)
/// for (int j2 = 0; j2 < 7; ++j2)
/// body(i1*3+i2, j1*3+j2);
/// \endcode
///
/// The returned vector are the loops {i1,j1,i2,j2}. The loops i1 and j1 are
/// referred to the floor, and the loops i2 and j2 are the tiles. Tiling also
/// handles non-constant trip counts, non-constant tile sizes and trip counts
/// that are not multiples of the tile size. In the latter case the tile loop
/// of the last floor-loop iteration will have fewer iterations than specified
/// as its tile size.
///
///
/// @param DL Debug location for instructions added by tiling, for
/// instance the floor- and tile trip count computation.
/// @param Loops Loops to tile. The CanonicalLoopInfo objects are
/// invalidated by this method, i.e. should not used after
/// tiling.
/// @param TileSizes For each loop in \p Loops, the tile size for that
/// dimensions.
///
/// \returns A list of generated loops. Contains twice as many loops as the
/// input loop nest; the first half are the floor loops and the
/// second half are the tile loops.
std::vector<CanonicalLoopInfo *>
tileLoops(DebugLoc DL, ArrayRef<CanonicalLoopInfo *> Loops,
ArrayRef<Value *> TileSizes);
/// Generator for '#omp flush'
///
/// \param Loc The location where the flush directive was encountered
void createFlush(const LocationDescription &Loc);
/// Generator for '#omp taskwait'
///
/// \param Loc The location where the taskwait directive was encountered.
void createTaskwait(const LocationDescription &Loc);
/// Generator for '#omp taskyield'
///
/// \param Loc The location where the taskyield directive was encountered.
void createTaskyield(const LocationDescription &Loc);
///}
/// Return the insertion point used by the underlying IRBuilder.
InsertPointTy getInsertionPoint() { return Builder.saveIP(); }
/// Update the internal location to \p Loc.
bool updateToLocation(const LocationDescription &Loc) {
Builder.restoreIP(Loc.IP);
Builder.SetCurrentDebugLocation(Loc.DL);
return Loc.IP.getBlock() != nullptr;
}
/// Return the function declaration for the runtime function with \p FnID.
FunctionCallee getOrCreateRuntimeFunction(Module &M,
omp::RuntimeFunction FnID);
Function *getOrCreateRuntimeFunctionPtr(omp::RuntimeFunction FnID);
/// Return the (LLVM-IR) string describing the source location \p LocStr.
Constant *getOrCreateSrcLocStr(StringRef LocStr);
/// Return the (LLVM-IR) string describing the default source location.
Constant *getOrCreateDefaultSrcLocStr();
/// Return the (LLVM-IR) string describing the source location identified by
/// the arguments.
Constant *getOrCreateSrcLocStr(StringRef FunctionName, StringRef FileName,
unsigned Line, unsigned Column);
/// Return the (LLVM-IR) string describing the source location \p Loc.
Constant *getOrCreateSrcLocStr(const LocationDescription &Loc);
/// Return an ident_t* encoding the source location \p SrcLocStr and \p Flags.
/// TODO: Create a enum class for the Reserve2Flags
Value *getOrCreateIdent(Constant *SrcLocStr,
omp::IdentFlag Flags = omp::IdentFlag(0),
unsigned Reserve2Flags = 0);
// Get the type corresponding to __kmpc_impl_lanemask_t from the deviceRTL
Type *getLanemaskType();
/// Generate control flow and cleanup for cancellation.
///
/// \param CancelFlag Flag indicating if the cancellation is performed.
/// \param CanceledDirective The kind of directive that is cancled.
void emitCancelationCheckImpl(Value *CancelFlag,
omp::Directive CanceledDirective);
/// Generate a barrier runtime call.
///
/// \param Loc The location at which the request originated and is fulfilled.
/// \param DK The directive which caused the barrier
/// \param ForceSimpleCall Flag to force a simple (=non-cancellation) barrier.
/// \param CheckCancelFlag Flag to indicate a cancel barrier return value
/// should be checked and acted upon.
///
/// \returns The insertion point after the barrier.
InsertPointTy emitBarrierImpl(const LocationDescription &Loc,
omp::Directive DK, bool ForceSimpleCall,
bool CheckCancelFlag);
/// Generate a flush runtime call.
///
/// \param Loc The location at which the request originated and is fulfilled.
void emitFlush(const LocationDescription &Loc);
/// The finalization stack made up of finalize callbacks currently in-flight,
/// wrapped into FinalizationInfo objects that reference also the finalization
/// target block and the kind of cancellable directive.
SmallVector<FinalizationInfo, 8> FinalizationStack;
/// Return true if the last entry in the finalization stack is of kind \p DK
/// and cancellable.
bool isLastFinalizationInfoCancellable(omp::Directive DK) {
return !FinalizationStack.empty() &&
FinalizationStack.back().IsCancellable &&
FinalizationStack.back().DK == DK;
}
/// Generate a taskwait runtime call.
///
/// \param Loc The location at which the request originated and is fulfilled.
void emitTaskwaitImpl(const LocationDescription &Loc);
/// Generate a taskyield runtime call.
///
/// \param Loc The location at which the request originated and is fulfilled.
void emitTaskyieldImpl(const LocationDescription &Loc);
/// Return the current thread ID.
///
/// \param Ident The ident (ident_t*) describing the query origin.
Value *getOrCreateThreadID(Value *Ident);
/// The underlying LLVM-IR module
Module &M;
/// The LLVM-IR Builder used to create IR.
IRBuilder<> Builder;
/// Map to remember source location strings
StringMap<Constant *> SrcLocStrMap;
/// Map to remember existing ident_t*.
DenseMap<std::pair<Constant *, uint64_t>, Value *> IdentMap;
/// Helper that contains information about regions we need to outline
/// during finalization.
struct OutlineInfo {
using PostOutlineCBTy = std::function<void(Function &)>;
PostOutlineCBTy PostOutlineCB;
BasicBlock *EntryBB, *ExitBB;
/// Collect all blocks in between EntryBB and ExitBB in both the given
/// vector and set.
void collectBlocks(SmallPtrSetImpl<BasicBlock *> &BlockSet,
SmallVectorImpl<BasicBlock *> &BlockVector);
};
/// Collection of regions that need to be outlined during finalization.
SmallVector<OutlineInfo, 16> OutlineInfos;
/// Collection of owned canonical loop objects that eventually need to be
/// free'd.
std::forward_list<CanonicalLoopInfo> LoopInfos;
/// Add a new region that will be outlined later.
void addOutlineInfo(OutlineInfo &&OI) { OutlineInfos.emplace_back(OI); }
/// An ordered map of auto-generated variables to their unique names.
/// It stores variables with the following names: 1) ".gomp_critical_user_" +
/// <critical_section_name> + ".var" for "omp critical" directives; 2)
/// <mangled_name_for_global_var> + ".cache." for cache for threadprivate
/// variables.
StringMap<AssertingVH<Constant>, BumpPtrAllocator> InternalVars;
public:
/// Generator for __kmpc_copyprivate
///
/// \param Loc The source location description.
/// \param BufSize Number of elements in the buffer.
/// \param CpyBuf List of pointers to data to be copied.
/// \param CpyFn function to call for copying data.
/// \param DidIt flag variable; 1 for 'single' thread, 0 otherwise.
///
/// \return The insertion position *after* the CopyPrivate call.
InsertPointTy createCopyPrivate(const LocationDescription &Loc,
llvm::Value *BufSize, llvm::Value *CpyBuf,
llvm::Value *CpyFn, llvm::Value *DidIt);
/// Generator for '#omp single'
///
/// \param Loc The source location description.
/// \param BodyGenCB Callback that will generate the region code.
/// \param FiniCB Callback to finalize variable copies.
/// \param DidIt Local variable used as a flag to indicate 'single' thread
///
/// \returns The insertion position *after* the single call.
InsertPointTy createSingle(const LocationDescription &Loc,
BodyGenCallbackTy BodyGenCB,
FinalizeCallbackTy FiniCB, llvm::Value *DidIt);
/// Generator for '#omp master'
///
/// \param Loc The insert and source location description.
/// \param BodyGenCB Callback that will generate the region code.
/// \param FiniCB Callback to finalize variable copies.
///
/// \returns The insertion position *after* the master.
InsertPointTy createMaster(const LocationDescription &Loc,
BodyGenCallbackTy BodyGenCB,
FinalizeCallbackTy FiniCB);
/// Generator for '#omp critical'
///
/// \param Loc The insert and source location description.
/// \param BodyGenCB Callback that will generate the region body code.
/// \param FiniCB Callback to finalize variable copies.
/// \param CriticalName name of the lock used by the critical directive
/// \param HintInst Hint Instruction for hint clause associated with critical
///
/// \returns The insertion position *after* the master.
InsertPointTy createCritical(const LocationDescription &Loc,
BodyGenCallbackTy BodyGenCB,
FinalizeCallbackTy FiniCB,
StringRef CriticalName, Value *HintInst);
/// Generate conditional branch and relevant BasicBlocks through which private
/// threads copy the 'copyin' variables from Master copy to threadprivate
/// copies.
///
/// \param IP insertion block for copyin conditional
/// \param MasterVarPtr a pointer to the master variable
/// \param PrivateVarPtr a pointer to the threadprivate variable
/// \param IntPtrTy Pointer size type
/// \param BranchtoEnd Create a branch between the copyin.not.master blocks
// and copy.in.end block
///
/// \returns The insertion point where copying operation to be emitted.
InsertPointTy createCopyinClauseBlocks(InsertPointTy IP, Value *MasterAddr,
Value *PrivateAddr,
llvm::IntegerType *IntPtrTy,
bool BranchtoEnd = true);
/// Create a runtime call for kmpc_Alloc
///
/// \param Loc The insert and source location description.
/// \param Size Size of allocated memory space
/// \param Allocator Allocator information instruction
/// \param Name Name of call Instruction for OMP_alloc
///
/// \returns CallInst to the OMP_Alloc call
CallInst *createOMPAlloc(const LocationDescription &Loc, Value *Size,
Value *Allocator, std::string Name = "");
/// Create a runtime call for kmpc_free
///
/// \param Loc The insert and source location description.
/// \param Addr Address of memory space to be freed
/// \param Allocator Allocator information instruction
/// \param Name Name of call Instruction for OMP_Free
///
/// \returns CallInst to the OMP_Free call
CallInst *createOMPFree(const LocationDescription &Loc, Value *Addr,
Value *Allocator, std::string Name = "");
/// Create a runtime call for kmpc_threadprivate_cached
///
/// \param Loc The insert and source location description.
/// \param Pointer pointer to data to be cached
/// \param Size size of data to be cached
/// \param Name Name of call Instruction for callinst
///
/// \returns CallInst to the thread private cache call.
CallInst *createCachedThreadPrivate(const LocationDescription &Loc,
llvm::Value *Pointer,
llvm::ConstantInt *Size,
const llvm::Twine &Name = Twine(""));
/// Declarations for LLVM-IR types (simple, array, function and structure) are
/// generated below. Their names are defined and used in OpenMPKinds.def. Here
/// we provide the declarations, the initializeTypes function will provide the
/// values.
///
///{
#define OMP_TYPE(VarName, InitValue) Type *VarName = nullptr;
#define OMP_ARRAY_TYPE(VarName, ElemTy, ArraySize) \
ArrayType *VarName##Ty = nullptr; \
PointerType *VarName##PtrTy = nullptr;
#define OMP_FUNCTION_TYPE(VarName, IsVarArg, ReturnType, ...) \
FunctionType *VarName = nullptr; \
PointerType *VarName##Ptr = nullptr;
#define OMP_STRUCT_TYPE(VarName, StrName, ...) \
StructType *VarName = nullptr; \
PointerType *VarName##Ptr = nullptr;
#include "llvm/Frontend/OpenMP/OMPKinds.def"
///}
private:
/// Create all simple and struct types exposed by the runtime and remember
/// the llvm::PointerTypes of them for easy access later.
void initializeTypes(Module &M);
/// Common interface for generating entry calls for OMP Directives.
/// if the directive has a region/body, It will set the insertion
/// point to the body
///
/// \param OMPD Directive to generate entry blocks for
/// \param EntryCall Call to the entry OMP Runtime Function
/// \param ExitBB block where the region ends.
/// \param Conditional indicate if the entry call result will be used
/// to evaluate a conditional of whether a thread will execute
/// body code or not.
///
/// \return The insertion position in exit block
InsertPointTy emitCommonDirectiveEntry(omp::Directive OMPD, Value *EntryCall,
BasicBlock *ExitBB,
bool Conditional = false);
/// Common interface to finalize the region
///
/// \param OMPD Directive to generate exiting code for
/// \param FinIP Insertion point for emitting Finalization code and exit call
/// \param ExitCall Call to the ending OMP Runtime Function
/// \param HasFinalize indicate if the directive will require finalization
/// and has a finalization callback in the stack that
/// should be called.
///
/// \return The insertion position in exit block
InsertPointTy emitCommonDirectiveExit(omp::Directive OMPD,
InsertPointTy FinIP,
Instruction *ExitCall,
bool HasFinalize = true);
/// Common Interface to generate OMP inlined regions
///
/// \param OMPD Directive to generate inlined region for
/// \param EntryCall Call to the entry OMP Runtime Function
/// \param ExitCall Call to the ending OMP Runtime Function
/// \param BodyGenCB Body code generation callback.
/// \param FiniCB Finalization Callback. Will be called when finalizing region
/// \param Conditional indicate if the entry call result will be used
/// to evaluate a conditional of whether a thread will execute
/// body code or not.
/// \param HasFinalize indicate if the directive will require finalization
/// and has a finalization callback in the stack that
/// should be called.
///
/// \return The insertion point after the region
InsertPointTy
EmitOMPInlinedRegion(omp::Directive OMPD, Instruction *EntryCall,
Instruction *ExitCall, BodyGenCallbackTy BodyGenCB,
FinalizeCallbackTy FiniCB, bool Conditional = false,
bool HasFinalize = true);
/// Get the platform-specific name separator.
/// \param Parts different parts of the final name that needs separation
/// \param FirstSeparator First separator used between the initial two
/// parts of the name.
/// \param Separator separator used between all of the rest consecutive
/// parts of the name
static std::string getNameWithSeparators(ArrayRef<StringRef> Parts,
StringRef FirstSeparator,
StringRef Separator);
/// Gets (if variable with the given name already exist) or creates
/// internal global variable with the specified Name. The created variable has
/// linkage CommonLinkage by default and is initialized by null value.
/// \param Ty Type of the global variable. If it is exist already the type
/// must be the same.
/// \param Name Name of the variable.
Constant *getOrCreateOMPInternalVariable(Type *Ty, const Twine &Name,
unsigned AddressSpace = 0);
/// Returns corresponding lock object for the specified critical region
/// name. If the lock object does not exist it is created, otherwise the
/// reference to the existing copy is returned.
/// \param CriticalName Name of the critical region.
///
Value *getOMPCriticalRegionLock(StringRef CriticalName);
/// Create the control flow structure of a canonical OpenMP loop.
///
/// The emitted loop will be disconnected, i.e. no edge to the loop's
/// preheader and no terminator in the AfterBB. The OpenMPIRBuilder's
/// IRBuilder location is not preserved.
///
/// \param DL DebugLoc used for the instructions in the skeleton.
/// \param TripCount Value to be used for the trip count.
/// \param F Function in which to insert the BasicBlocks.
/// \param PreInsertBefore Where to insert BBs that execute before the body,
/// typically the body itself.
/// \param PostInsertBefore Where to insert BBs that execute after the body.
/// \param Name Base name used to derive BB
/// and instruction names.
///
/// \returns The CanonicalLoopInfo that represents the emitted loop.
CanonicalLoopInfo *createLoopSkeleton(DebugLoc DL, Value *TripCount,
Function *F,
BasicBlock *PreInsertBefore,
BasicBlock *PostInsertBefore,
const Twine &Name = {});
};
/// Class to represented the control flow structure of an OpenMP canonical loop.
///
/// The control-flow structure is standardized for easy consumption by
/// directives associated with loops. For instance, the worksharing-loop
/// construct may change this control flow such that each loop iteration is
/// executed on only one thread.
///
/// The control flow can be described as follows:
///
/// Preheader
/// |
/// /-> Header
/// | |
/// | Cond---\
/// | | |
/// | Body |
/// | | | |
/// | <...> |
/// | | | |
/// \--Latch |
/// |
/// Exit
/// |
/// After
///
/// Code in the header, condition block, latch and exit block must not have any
/// side-effect. The body block is the single entry point into the loop body,
/// which may contain arbitrary control flow as long as all control paths
/// eventually branch to the latch block.
///
/// Defined outside OpenMPIRBuilder because one cannot forward-declare nested
/// classes.
class CanonicalLoopInfo {
friend class OpenMPIRBuilder;
private:
/// Whether this object currently represents a loop.
bool IsValid = false;
BasicBlock *Preheader;
BasicBlock *Header;
BasicBlock *Cond;
BasicBlock *Body;
BasicBlock *Latch;
BasicBlock *Exit;
BasicBlock *After;
/// Add the control blocks of this loop to \p BBs.
///
/// This does not include any block from the body, including the one returned
/// by getBody().
void collectControlBlocks(SmallVectorImpl<BasicBlock *> &BBs);
public:
/// The preheader ensures that there is only a single edge entering the loop.
/// Code that must be execute before any loop iteration can be emitted here,
/// such as computing the loop trip count and begin lifetime markers. Code in
/// the preheader is not considered part of the canonical loop.
BasicBlock *getPreheader() const { return Preheader; }
/// The header is the entry for each iteration. In the canonical control flow,
/// it only contains the PHINode for the induction variable.
BasicBlock *getHeader() const { return Header; }
/// The condition block computes whether there is another loop iteration. If
/// yes, branches to the body; otherwise to the exit block.
BasicBlock *getCond() const { return Cond; }
/// The body block is the single entry for a loop iteration and not controlled
/// by CanonicalLoopInfo. It can contain arbitrary control flow but must
/// eventually branch to the \p Latch block.
BasicBlock *getBody() const { return Body; }
/// Reaching the latch indicates the end of the loop body code. In the
/// canonical control flow, it only contains the increment of the induction
/// variable.
BasicBlock *getLatch() const { return Latch; }
/// Reaching the exit indicates no more iterations are being executed.
BasicBlock *getExit() const { return Exit; }
/// The after block is intended for clean-up code such as lifetime end
/// markers. It is separate from the exit block to ensure, analogous to the
/// preheader, it having just a single entry edge and being free from PHI
/// nodes should there be multiple loop exits (such as from break
/// statements/cancellations).
BasicBlock *getAfter() const { return After; }
/// Returns the llvm::Value containing the number of loop iterations. It must
/// be valid in the preheader and always interpreted as an unsigned integer of
/// any bit-width.
Value *getTripCount() const {
Instruction *CmpI = &Cond->front();
assert(isa<CmpInst>(CmpI) && "First inst must compare IV with TripCount");
return CmpI->getOperand(1);
}
/// Returns the instruction representing the current logical induction
/// variable. Always unsigned, always starting at 0 with an increment of one.
Instruction *getIndVar() const {
Instruction *IndVarPHI = &Header->front();
assert(isa<PHINode>(IndVarPHI) && "First inst must be the IV PHI");
return IndVarPHI;
}
/// Return the type of the induction variable (and the trip count).
Type *getIndVarType() const { return getIndVar()->getType(); }
/// Return the insertion point for user code before the loop.
OpenMPIRBuilder::InsertPointTy getPreheaderIP() const {
return {Preheader, std::prev(Preheader->end())};
};
/// Return the insertion point for user code in the body.
OpenMPIRBuilder::InsertPointTy getBodyIP() const {
return {Body, Body->begin()};
};
/// Return the insertion point for user code after the loop.
OpenMPIRBuilder::InsertPointTy getAfterIP() const {
return {After, After->begin()};
};
/// Consistency self-check.
void assertOK() const;
};
} // end namespace llvm
#endif // LLVM_IR_IRBUILDER_H
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