1 //===----- CGOpenMPRuntime.h - Interface to OpenMP Runtimes -----*- C++ -*-===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This provides a class for OpenMP runtime code generation.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #ifndef LLVM_CLANG_LIB_CODEGEN_CGOPENMPRUNTIME_H
15 #define LLVM_CLANG_LIB_CODEGEN_CGOPENMPRUNTIME_H
16 
17 #include "clang/AST/Type.h"
18 #include "clang/Basic/OpenMPKinds.h"
19 #include "clang/Basic/SourceLocation.h"
20 #include "llvm/ADT/DenseMap.h"
21 #include "llvm/ADT/DenseSet.h"
22 #include "llvm/ADT/StringMap.h"
23 #include "llvm/IR/ValueHandle.h"
24 
25 namespace llvm {
26 class ArrayType;
27 class Constant;
28 class Function;
29 class FunctionType;
30 class GlobalVariable;
31 class StructType;
32 class Type;
33 class Value;
34 } // namespace llvm
35 
36 namespace clang {
37 class Expr;
38 class OMPExecutableDirective;
39 class VarDecl;
40 
41 namespace CodeGen {
42 class Address;
43 class CodeGenFunction;
44 class CodeGenModule;
45 
46 typedef llvm::function_ref<void(CodeGenFunction &)> RegionCodeGenTy;
47 
48 class CGOpenMPRuntime {
49 private:
50   enum OpenMPRTLFunction {
51     /// \brief Call to void __kmpc_fork_call(ident_t *loc, kmp_int32 argc,
52     /// kmpc_micro microtask, ...);
53     OMPRTL__kmpc_fork_call,
54     /// \brief Call to void *__kmpc_threadprivate_cached(ident_t *loc,
55     /// kmp_int32 global_tid, void *data, size_t size, void ***cache);
56     OMPRTL__kmpc_threadprivate_cached,
57     /// \brief Call to void __kmpc_threadprivate_register( ident_t *,
58     /// void *data, kmpc_ctor ctor, kmpc_cctor cctor, kmpc_dtor dtor);
59     OMPRTL__kmpc_threadprivate_register,
60     // Call to __kmpc_int32 kmpc_global_thread_num(ident_t *loc);
61     OMPRTL__kmpc_global_thread_num,
62     // Call to void __kmpc_critical(ident_t *loc, kmp_int32 global_tid,
63     // kmp_critical_name *crit);
64     OMPRTL__kmpc_critical,
65     // Call to void __kmpc_critical_with_hint(ident_t *loc, kmp_int32
66     // global_tid, kmp_critical_name *crit, uintptr_t hint);
67     OMPRTL__kmpc_critical_with_hint,
68     // Call to void __kmpc_end_critical(ident_t *loc, kmp_int32 global_tid,
69     // kmp_critical_name *crit);
70     OMPRTL__kmpc_end_critical,
71     // Call to kmp_int32 __kmpc_cancel_barrier(ident_t *loc, kmp_int32
72     // global_tid);
73     OMPRTL__kmpc_cancel_barrier,
74     // Call to void __kmpc_barrier(ident_t *loc, kmp_int32 global_tid);
75     OMPRTL__kmpc_barrier,
76     // Call to void __kmpc_for_static_fini(ident_t *loc, kmp_int32 global_tid);
77     OMPRTL__kmpc_for_static_fini,
78     // Call to void __kmpc_serialized_parallel(ident_t *loc, kmp_int32
79     // global_tid);
80     OMPRTL__kmpc_serialized_parallel,
81     // Call to void __kmpc_end_serialized_parallel(ident_t *loc, kmp_int32
82     // global_tid);
83     OMPRTL__kmpc_end_serialized_parallel,
84     // Call to void __kmpc_push_num_threads(ident_t *loc, kmp_int32 global_tid,
85     // kmp_int32 num_threads);
86     OMPRTL__kmpc_push_num_threads,
87     // Call to void __kmpc_flush(ident_t *loc);
88     OMPRTL__kmpc_flush,
89     // Call to kmp_int32 __kmpc_master(ident_t *, kmp_int32 global_tid);
90     OMPRTL__kmpc_master,
91     // Call to void __kmpc_end_master(ident_t *, kmp_int32 global_tid);
92     OMPRTL__kmpc_end_master,
93     // Call to kmp_int32 __kmpc_omp_taskyield(ident_t *, kmp_int32 global_tid,
94     // int end_part);
95     OMPRTL__kmpc_omp_taskyield,
96     // Call to kmp_int32 __kmpc_single(ident_t *, kmp_int32 global_tid);
97     OMPRTL__kmpc_single,
98     // Call to void __kmpc_end_single(ident_t *, kmp_int32 global_tid);
99     OMPRTL__kmpc_end_single,
100     // Call to kmp_task_t * __kmpc_omp_task_alloc(ident_t *, kmp_int32 gtid,
101     // kmp_int32 flags, size_t sizeof_kmp_task_t, size_t sizeof_shareds,
102     // kmp_routine_entry_t *task_entry);
103     OMPRTL__kmpc_omp_task_alloc,
104     // Call to kmp_int32 __kmpc_omp_task(ident_t *, kmp_int32 gtid, kmp_task_t *
105     // new_task);
106     OMPRTL__kmpc_omp_task,
107     // Call to void __kmpc_copyprivate(ident_t *loc, kmp_int32 global_tid,
108     // size_t cpy_size, void *cpy_data, void(*cpy_func)(void *, void *),
109     // kmp_int32 didit);
110     OMPRTL__kmpc_copyprivate,
111     // Call to kmp_int32 __kmpc_reduce(ident_t *loc, kmp_int32 global_tid,
112     // kmp_int32 num_vars, size_t reduce_size, void *reduce_data, void
113     // (*reduce_func)(void *lhs_data, void *rhs_data), kmp_critical_name *lck);
114     OMPRTL__kmpc_reduce,
115     // Call to kmp_int32 __kmpc_reduce_nowait(ident_t *loc, kmp_int32
116     // global_tid, kmp_int32 num_vars, size_t reduce_size, void *reduce_data,
117     // void (*reduce_func)(void *lhs_data, void *rhs_data), kmp_critical_name
118     // *lck);
119     OMPRTL__kmpc_reduce_nowait,
120     // Call to void __kmpc_end_reduce(ident_t *loc, kmp_int32 global_tid,
121     // kmp_critical_name *lck);
122     OMPRTL__kmpc_end_reduce,
123     // Call to void __kmpc_end_reduce_nowait(ident_t *loc, kmp_int32 global_tid,
124     // kmp_critical_name *lck);
125     OMPRTL__kmpc_end_reduce_nowait,
126     // Call to void __kmpc_omp_task_begin_if0(ident_t *, kmp_int32 gtid,
127     // kmp_task_t * new_task);
128     OMPRTL__kmpc_omp_task_begin_if0,
129     // Call to void __kmpc_omp_task_complete_if0(ident_t *, kmp_int32 gtid,
130     // kmp_task_t * new_task);
131     OMPRTL__kmpc_omp_task_complete_if0,
132     // Call to void __kmpc_ordered(ident_t *loc, kmp_int32 global_tid);
133     OMPRTL__kmpc_ordered,
134     // Call to void __kmpc_end_ordered(ident_t *loc, kmp_int32 global_tid);
135     OMPRTL__kmpc_end_ordered,
136     // Call to kmp_int32 __kmpc_omp_taskwait(ident_t *loc, kmp_int32
137     // global_tid);
138     OMPRTL__kmpc_omp_taskwait,
139     // Call to void __kmpc_taskgroup(ident_t *loc, kmp_int32 global_tid);
140     OMPRTL__kmpc_taskgroup,
141     // Call to void __kmpc_end_taskgroup(ident_t *loc, kmp_int32 global_tid);
142     OMPRTL__kmpc_end_taskgroup,
143     // Call to void __kmpc_push_proc_bind(ident_t *loc, kmp_int32 global_tid,
144     // int proc_bind);
145     OMPRTL__kmpc_push_proc_bind,
146     // Call to kmp_int32 __kmpc_omp_task_with_deps(ident_t *loc_ref, kmp_int32
147     // gtid, kmp_task_t * new_task, kmp_int32 ndeps, kmp_depend_info_t
148     // *dep_list, kmp_int32 ndeps_noalias, kmp_depend_info_t *noalias_dep_list);
149     OMPRTL__kmpc_omp_task_with_deps,
150     // Call to void __kmpc_omp_wait_deps(ident_t *loc_ref, kmp_int32
151     // gtid, kmp_int32 ndeps, kmp_depend_info_t *dep_list, kmp_int32
152     // ndeps_noalias, kmp_depend_info_t *noalias_dep_list);
153     OMPRTL__kmpc_omp_wait_deps,
154     // Call to kmp_int32 __kmpc_cancellationpoint(ident_t *loc, kmp_int32
155     // global_tid, kmp_int32 cncl_kind);
156     OMPRTL__kmpc_cancellationpoint,
157     // Call to kmp_int32 __kmpc_cancel(ident_t *loc, kmp_int32 global_tid,
158     // kmp_int32 cncl_kind);
159     OMPRTL__kmpc_cancel,
160 
161     //
162     // Offloading related calls
163     //
164     // Call to int32_t __tgt_target(int32_t device_id, void *host_ptr, int32_t
165     // arg_num, void** args_base, void **args, size_t *arg_sizes, int32_t
166     // *arg_types);
167     OMPRTL__tgt_target,
168   };
169 
170   /// \brief Values for bit flags used in the ident_t to describe the fields.
171   /// All enumeric elements are named and described in accordance with the code
172   /// from http://llvm.org/svn/llvm-project/openmp/trunk/runtime/src/kmp.h
173   enum OpenMPLocationFlags {
174     /// \brief Use trampoline for internal microtask.
175     OMP_IDENT_IMD = 0x01,
176     /// \brief Use c-style ident structure.
177     OMP_IDENT_KMPC = 0x02,
178     /// \brief Atomic reduction option for kmpc_reduce.
179     OMP_ATOMIC_REDUCE = 0x10,
180     /// \brief Explicit 'barrier' directive.
181     OMP_IDENT_BARRIER_EXPL = 0x20,
182     /// \brief Implicit barrier in code.
183     OMP_IDENT_BARRIER_IMPL = 0x40,
184     /// \brief Implicit barrier in 'for' directive.
185     OMP_IDENT_BARRIER_IMPL_FOR = 0x40,
186     /// \brief Implicit barrier in 'sections' directive.
187     OMP_IDENT_BARRIER_IMPL_SECTIONS = 0xC0,
188     /// \brief Implicit barrier in 'single' directive.
189     OMP_IDENT_BARRIER_IMPL_SINGLE = 0x140
190   };
191   CodeGenModule &CGM;
192   /// \brief Default const ident_t object used for initialization of all other
193   /// ident_t objects.
194   llvm::Constant *DefaultOpenMPPSource;
195   /// \brief Map of flags and corresponding default locations.
196   typedef llvm::DenseMap<unsigned, llvm::Value *> OpenMPDefaultLocMapTy;
197   OpenMPDefaultLocMapTy OpenMPDefaultLocMap;
198   Address getOrCreateDefaultLocation(OpenMPLocationFlags Flags);
199 
200 public:
201   /// \brief Describes ident structure that describes a source location.
202   /// All descriptions are taken from
203   /// http://llvm.org/svn/llvm-project/openmp/trunk/runtime/src/kmp.h
204   /// Original structure:
205   /// typedef struct ident {
206   ///    kmp_int32 reserved_1;   /**<  might be used in Fortran;
207   ///                                  see above  */
208   ///    kmp_int32 flags;        /**<  also f.flags; KMP_IDENT_xxx flags;
209   ///                                  KMP_IDENT_KMPC identifies this union
210   ///                                  member  */
211   ///    kmp_int32 reserved_2;   /**<  not really used in Fortran any more;
212   ///                                  see above */
213   ///#if USE_ITT_BUILD
214   ///                            /*  but currently used for storing
215   ///                                region-specific ITT */
216   ///                            /*  contextual information. */
217   ///#endif /* USE_ITT_BUILD */
218   ///    kmp_int32 reserved_3;   /**< source[4] in Fortran, do not use for
219   ///                                 C++  */
220   ///    char const *psource;    /**< String describing the source location.
221   ///                            The string is composed of semi-colon separated
222   //                             fields which describe the source file,
223   ///                            the function and a pair of line numbers that
224   ///                            delimit the construct.
225   ///                             */
226   /// } ident_t;
227   enum IdentFieldIndex {
228     /// \brief might be used in Fortran
229     IdentField_Reserved_1,
230     /// \brief OMP_IDENT_xxx flags; OMP_IDENT_KMPC identifies this union member.
231     IdentField_Flags,
232     /// \brief Not really used in Fortran any more
233     IdentField_Reserved_2,
234     /// \brief Source[4] in Fortran, do not use for C++
235     IdentField_Reserved_3,
236     /// \brief String describing the source location. The string is composed of
237     /// semi-colon separated fields which describe the source file, the function
238     /// and a pair of line numbers that delimit the construct.
239     IdentField_PSource
240   };
241 private:
242   llvm::StructType *IdentTy;
243   /// \brief Map for SourceLocation and OpenMP runtime library debug locations.
244   typedef llvm::DenseMap<unsigned, llvm::Value *> OpenMPDebugLocMapTy;
245   OpenMPDebugLocMapTy OpenMPDebugLocMap;
246   /// \brief The type for a microtask which gets passed to __kmpc_fork_call().
247   /// Original representation is:
248   /// typedef void (kmpc_micro)(kmp_int32 global_tid, kmp_int32 bound_tid,...);
249   llvm::FunctionType *Kmpc_MicroTy;
250   /// \brief Stores debug location and ThreadID for the function.
251   struct DebugLocThreadIdTy {
252     llvm::Value *DebugLoc;
253     llvm::Value *ThreadID;
254   };
255   /// \brief Map of local debug location, ThreadId and functions.
256   typedef llvm::DenseMap<llvm::Function *, DebugLocThreadIdTy>
257       OpenMPLocThreadIDMapTy;
258   OpenMPLocThreadIDMapTy OpenMPLocThreadIDMap;
259   /// \brief Type kmp_critical_name, originally defined as typedef kmp_int32
260   /// kmp_critical_name[8];
261   llvm::ArrayType *KmpCriticalNameTy;
262   /// \brief An ordered map of auto-generated variables to their unique names.
263   /// It stores variables with the following names: 1) ".gomp_critical_user_" +
264   /// <critical_section_name> + ".var" for "omp critical" directives; 2)
265   /// <mangled_name_for_global_var> + ".cache." for cache for threadprivate
266   /// variables.
267   llvm::StringMap<llvm::AssertingVH<llvm::Constant>, llvm::BumpPtrAllocator>
268       InternalVars;
269   /// \brief Type typedef kmp_int32 (* kmp_routine_entry_t)(kmp_int32, void *);
270   llvm::Type *KmpRoutineEntryPtrTy;
271   QualType KmpRoutineEntryPtrQTy;
272   /// \brief Type typedef struct kmp_task {
273   ///    void *              shareds; /**< pointer to block of pointers to
274   ///    shared vars   */
275   ///    kmp_routine_entry_t routine; /**< pointer to routine to call for
276   ///    executing task */
277   ///    kmp_int32           part_id; /**< part id for the task */
278   ///    kmp_routine_entry_t destructors; /* pointer to function to invoke
279   ///    deconstructors of firstprivate C++ objects */
280   /// } kmp_task_t;
281   QualType KmpTaskTQTy;
282   /// \brief Type typedef struct kmp_depend_info {
283   ///    kmp_intptr_t               base_addr;
284   ///    size_t                     len;
285   ///    struct {
286   ///             bool                   in:1;
287   ///             bool                   out:1;
288   ///    } flags;
289   /// } kmp_depend_info_t;
290   QualType KmpDependInfoTy;
291 
292 
293   /// \brief Build type kmp_routine_entry_t (if not built yet).
294   void emitKmpRoutineEntryT(QualType KmpInt32Ty);
295 
296   /// \brief Emits object of ident_t type with info for source location.
297   /// \param Flags Flags for OpenMP location.
298   ///
299   llvm::Value *emitUpdateLocation(CodeGenFunction &CGF, SourceLocation Loc,
300                                   OpenMPLocationFlags Flags = OMP_IDENT_KMPC);
301 
302   /// \brief Returns pointer to ident_t type.
303   llvm::Type *getIdentTyPointerTy();
304 
305   /// \brief Returns pointer to kmpc_micro type.
306   llvm::Type *getKmpc_MicroPointerTy();
307 
308   /// \brief Returns specified OpenMP runtime function.
309   /// \param Function OpenMP runtime function.
310   /// \return Specified function.
311   llvm::Constant *createRuntimeFunction(OpenMPRTLFunction Function);
312 
313   /// \brief Returns __kmpc_for_static_init_* runtime function for the specified
314   /// size \a IVSize and sign \a IVSigned.
315   llvm::Constant *createForStaticInitFunction(unsigned IVSize, bool IVSigned);
316 
317   /// \brief Returns __kmpc_dispatch_init_* runtime function for the specified
318   /// size \a IVSize and sign \a IVSigned.
319   llvm::Constant *createDispatchInitFunction(unsigned IVSize, bool IVSigned);
320 
321   /// \brief Returns __kmpc_dispatch_next_* runtime function for the specified
322   /// size \a IVSize and sign \a IVSigned.
323   llvm::Constant *createDispatchNextFunction(unsigned IVSize, bool IVSigned);
324 
325   /// \brief Returns __kmpc_dispatch_fini_* runtime function for the specified
326   /// size \a IVSize and sign \a IVSigned.
327   llvm::Constant *createDispatchFiniFunction(unsigned IVSize, bool IVSigned);
328 
329   /// \brief If the specified mangled name is not in the module, create and
330   /// return threadprivate cache object. This object is a pointer's worth of
331   /// storage that's reserved for use by the OpenMP runtime.
332   /// \param VD Threadprivate variable.
333   /// \return Cache variable for the specified threadprivate.
334   llvm::Constant *getOrCreateThreadPrivateCache(const VarDecl *VD);
335 
336   /// \brief Emits address of the word in a memory where current thread id is
337   /// stored.
338   virtual Address emitThreadIDAddress(CodeGenFunction &CGF, SourceLocation Loc);
339 
340   /// \brief Gets thread id value for the current thread.
341   ///
342   llvm::Value *getThreadID(CodeGenFunction &CGF, SourceLocation Loc);
343 
344   /// \brief Gets (if variable with the given name already exist) or creates
345   /// internal global variable with the specified Name. The created variable has
346   /// linkage CommonLinkage by default and is initialized by null value.
347   /// \param Ty Type of the global variable. If it is exist already the type
348   /// must be the same.
349   /// \param Name Name of the variable.
350   llvm::Constant *getOrCreateInternalVariable(llvm::Type *Ty,
351                                               const llvm::Twine &Name);
352 
353   /// \brief Set of threadprivate variables with the generated initializer.
354   llvm::DenseSet<const VarDecl *> ThreadPrivateWithDefinition;
355 
356   /// \brief Emits initialization code for the threadprivate variables.
357   /// \param VDAddr Address of the global variable \a VD.
358   /// \param Ctor Pointer to a global init function for \a VD.
359   /// \param CopyCtor Pointer to a global copy function for \a VD.
360   /// \param Dtor Pointer to a global destructor function for \a VD.
361   /// \param Loc Location of threadprivate declaration.
362   void emitThreadPrivateVarInit(CodeGenFunction &CGF, Address VDAddr,
363                                 llvm::Value *Ctor, llvm::Value *CopyCtor,
364                                 llvm::Value *Dtor, SourceLocation Loc);
365 
366   /// \brief Returns corresponding lock object for the specified critical region
367   /// name. If the lock object does not exist it is created, otherwise the
368   /// reference to the existing copy is returned.
369   /// \param CriticalName Name of the critical region.
370   ///
371   llvm::Value *getCriticalRegionLock(StringRef CriticalName);
372 
373 public:
374   explicit CGOpenMPRuntime(CodeGenModule &CGM);
~CGOpenMPRuntime()375   virtual ~CGOpenMPRuntime() {}
376   virtual void clear();
377 
378   /// \brief Emits outlined function for the specified OpenMP parallel directive
379   /// \a D. This outlined function has type void(*)(kmp_int32 *ThreadID,
380   /// kmp_int32 BoundID, struct context_vars*).
381   /// \param D OpenMP directive.
382   /// \param ThreadIDVar Variable for thread id in the current OpenMP region.
383   /// \param InnermostKind Kind of innermost directive (for simple directives it
384   /// is a directive itself, for combined - its innermost directive).
385   /// \param CodeGen Code generation sequence for the \a D directive.
386   virtual llvm::Value *emitParallelOutlinedFunction(
387       const OMPExecutableDirective &D, const VarDecl *ThreadIDVar,
388       OpenMPDirectiveKind InnermostKind, const RegionCodeGenTy &CodeGen);
389 
390   /// \brief Emits outlined function for the OpenMP task directive \a D. This
391   /// outlined function has type void(*)(kmp_int32 ThreadID, kmp_int32
392   /// PartID, struct context_vars*).
393   /// \param D OpenMP directive.
394   /// \param ThreadIDVar Variable for thread id in the current OpenMP region.
395   /// \param InnermostKind Kind of innermost directive (for simple directives it
396   /// is a directive itself, for combined - its innermost directive).
397   /// \param CodeGen Code generation sequence for the \a D directive.
398   ///
399   virtual llvm::Value *emitTaskOutlinedFunction(
400       const OMPExecutableDirective &D, const VarDecl *ThreadIDVar,
401       OpenMPDirectiveKind InnermostKind, const RegionCodeGenTy &CodeGen);
402 
403   /// \brief Cleans up references to the objects in finished function.
404   ///
405   void functionFinished(CodeGenFunction &CGF);
406 
407   /// \brief Emits code for parallel or serial call of the \a OutlinedFn with
408   /// variables captured in a record which address is stored in \a
409   /// CapturedStruct.
410   /// \param OutlinedFn Outlined function to be run in parallel threads. Type of
411   /// this function is void(*)(kmp_int32 *, kmp_int32, struct context_vars*).
412   /// \param CapturedVars A pointer to the record with the references to
413   /// variables used in \a OutlinedFn function.
414   /// \param IfCond Condition in the associated 'if' clause, if it was
415   /// specified, nullptr otherwise.
416   ///
417   virtual void emitParallelCall(CodeGenFunction &CGF, SourceLocation Loc,
418                                 llvm::Value *OutlinedFn,
419                                 ArrayRef<llvm::Value *> CapturedVars,
420                                 const Expr *IfCond);
421 
422   /// \brief Emits a critical region.
423   /// \param CriticalName Name of the critical region.
424   /// \param CriticalOpGen Generator for the statement associated with the given
425   /// critical region.
426   /// \param Hint Value of the 'hint' clause (optional).
427   virtual void emitCriticalRegion(CodeGenFunction &CGF, StringRef CriticalName,
428                                   const RegionCodeGenTy &CriticalOpGen,
429                                   SourceLocation Loc,
430                                   const Expr *Hint = nullptr);
431 
432   /// \brief Emits a master region.
433   /// \param MasterOpGen Generator for the statement associated with the given
434   /// master region.
435   virtual void emitMasterRegion(CodeGenFunction &CGF,
436                                 const RegionCodeGenTy &MasterOpGen,
437                                 SourceLocation Loc);
438 
439   /// \brief Emits code for a taskyield directive.
440   virtual void emitTaskyieldCall(CodeGenFunction &CGF, SourceLocation Loc);
441 
442   /// \brief Emit a taskgroup region.
443   /// \param TaskgroupOpGen Generator for the statement associated with the
444   /// given taskgroup region.
445   virtual void emitTaskgroupRegion(CodeGenFunction &CGF,
446                                    const RegionCodeGenTy &TaskgroupOpGen,
447                                    SourceLocation Loc);
448 
449   /// \brief Emits a single region.
450   /// \param SingleOpGen Generator for the statement associated with the given
451   /// single region.
452   virtual void emitSingleRegion(CodeGenFunction &CGF,
453                                 const RegionCodeGenTy &SingleOpGen,
454                                 SourceLocation Loc,
455                                 ArrayRef<const Expr *> CopyprivateVars,
456                                 ArrayRef<const Expr *> DestExprs,
457                                 ArrayRef<const Expr *> SrcExprs,
458                                 ArrayRef<const Expr *> AssignmentOps);
459 
460   /// \brief Emit an ordered region.
461   /// \param OrderedOpGen Generator for the statement associated with the given
462   /// ordered region.
463   virtual void emitOrderedRegion(CodeGenFunction &CGF,
464                                  const RegionCodeGenTy &OrderedOpGen,
465                                  SourceLocation Loc, bool IsThreads);
466 
467   /// \brief Emit an implicit/explicit barrier for OpenMP threads.
468   /// \param Kind Directive for which this implicit barrier call must be
469   /// generated. Must be OMPD_barrier for explicit barrier generation.
470   /// \param EmitChecks true if need to emit checks for cancellation barriers.
471   /// \param ForceSimpleCall true simple barrier call must be emitted, false if
472   /// runtime class decides which one to emit (simple or with cancellation
473   /// checks).
474   ///
475   virtual void emitBarrierCall(CodeGenFunction &CGF, SourceLocation Loc,
476                                OpenMPDirectiveKind Kind,
477                                bool EmitChecks = true,
478                                bool ForceSimpleCall = false);
479 
480   /// \brief Check if the specified \a ScheduleKind is static non-chunked.
481   /// This kind of worksharing directive is emitted without outer loop.
482   /// \param ScheduleKind Schedule kind specified in the 'schedule' clause.
483   /// \param Chunked True if chunk is specified in the clause.
484   ///
485   virtual bool isStaticNonchunked(OpenMPScheduleClauseKind ScheduleKind,
486                                   bool Chunked) const;
487 
488   /// \brief Check if the specified \a ScheduleKind is dynamic.
489   /// This kind of worksharing directive is emitted without outer loop.
490   /// \param ScheduleKind Schedule Kind specified in the 'schedule' clause.
491   ///
492   virtual bool isDynamic(OpenMPScheduleClauseKind ScheduleKind) const;
493 
494   virtual void emitForDispatchInit(CodeGenFunction &CGF, SourceLocation Loc,
495                                    OpenMPScheduleClauseKind SchedKind,
496                                    unsigned IVSize, bool IVSigned,
497                                    bool Ordered, llvm::Value *UB,
498                                    llvm::Value *Chunk = nullptr);
499 
500   /// \brief Call the appropriate runtime routine to initialize it before start
501   /// of loop.
502   ///
503   /// Depending on the loop schedule, it is nesessary to call some runtime
504   /// routine before start of the OpenMP loop to get the loop upper / lower
505   /// bounds \a LB and \a UB and stride \a ST.
506   ///
507   /// \param CGF Reference to current CodeGenFunction.
508   /// \param Loc Clang source location.
509   /// \param SchedKind Schedule kind, specified by the 'schedule' clause.
510   /// \param IVSize Size of the iteration variable in bits.
511   /// \param IVSigned Sign of the interation variable.
512   /// \param Ordered true if loop is ordered, false otherwise.
513   /// \param IL Address of the output variable in which the flag of the
514   /// last iteration is returned.
515   /// \param LB Address of the output variable in which the lower iteration
516   /// number is returned.
517   /// \param UB Address of the output variable in which the upper iteration
518   /// number is returned.
519   /// \param ST Address of the output variable in which the stride value is
520   /// returned nesessary to generated the static_chunked scheduled loop.
521   /// \param Chunk Value of the chunk for the static_chunked scheduled loop.
522   /// For the default (nullptr) value, the chunk 1 will be used.
523   ///
524   virtual void emitForStaticInit(CodeGenFunction &CGF, SourceLocation Loc,
525                                  OpenMPScheduleClauseKind SchedKind,
526                                  unsigned IVSize, bool IVSigned, bool Ordered,
527                                  Address IL, Address LB,
528                                  Address UB, Address ST,
529                                  llvm::Value *Chunk = nullptr);
530 
531   /// \brief Call the appropriate runtime routine to notify that we finished
532   /// iteration of the ordered loop with the dynamic scheduling.
533   ///
534   /// \param CGF Reference to current CodeGenFunction.
535   /// \param Loc Clang source location.
536   /// \param IVSize Size of the iteration variable in bits.
537   /// \param IVSigned Sign of the interation variable.
538   ///
539   virtual void emitForOrderedIterationEnd(CodeGenFunction &CGF,
540                                           SourceLocation Loc, unsigned IVSize,
541                                           bool IVSigned);
542 
543   /// \brief Call the appropriate runtime routine to notify that we finished
544   /// all the work with current loop.
545   ///
546   /// \param CGF Reference to current CodeGenFunction.
547   /// \param Loc Clang source location.
548   ///
549   virtual void emitForStaticFinish(CodeGenFunction &CGF, SourceLocation Loc);
550 
551   /// Call __kmpc_dispatch_next(
552   ///          ident_t *loc, kmp_int32 tid, kmp_int32 *p_lastiter,
553   ///          kmp_int[32|64] *p_lower, kmp_int[32|64] *p_upper,
554   ///          kmp_int[32|64] *p_stride);
555   /// \param IVSize Size of the iteration variable in bits.
556   /// \param IVSigned Sign of the interation variable.
557   /// \param IL Address of the output variable in which the flag of the
558   /// last iteration is returned.
559   /// \param LB Address of the output variable in which the lower iteration
560   /// number is returned.
561   /// \param UB Address of the output variable in which the upper iteration
562   /// number is returned.
563   /// \param ST Address of the output variable in which the stride value is
564   /// returned.
565   virtual llvm::Value *emitForNext(CodeGenFunction &CGF, SourceLocation Loc,
566                                    unsigned IVSize, bool IVSigned,
567                                    Address IL, Address LB,
568                                    Address UB, Address ST);
569 
570   /// \brief Emits call to void __kmpc_push_num_threads(ident_t *loc, kmp_int32
571   /// global_tid, kmp_int32 num_threads) to generate code for 'num_threads'
572   /// clause.
573   /// \param NumThreads An integer value of threads.
574   virtual void emitNumThreadsClause(CodeGenFunction &CGF,
575                                     llvm::Value *NumThreads,
576                                     SourceLocation Loc);
577 
578   /// \brief Emit call to void __kmpc_push_proc_bind(ident_t *loc, kmp_int32
579   /// global_tid, int proc_bind) to generate code for 'proc_bind' clause.
580   virtual void emitProcBindClause(CodeGenFunction &CGF,
581                                   OpenMPProcBindClauseKind ProcBind,
582                                   SourceLocation Loc);
583 
584   /// \brief Returns address of the threadprivate variable for the current
585   /// thread.
586   /// \param VD Threadprivate variable.
587   /// \param VDAddr Address of the global variable \a VD.
588   /// \param Loc Location of the reference to threadprivate var.
589   /// \return Address of the threadprivate variable for the current thread.
590   virtual Address getAddrOfThreadPrivate(CodeGenFunction &CGF,
591                                          const VarDecl *VD,
592                                          Address VDAddr,
593                                          SourceLocation Loc);
594 
595   /// \brief Emit a code for initialization of threadprivate variable. It emits
596   /// a call to runtime library which adds initial value to the newly created
597   /// threadprivate variable (if it is not constant) and registers destructor
598   /// for the variable (if any).
599   /// \param VD Threadprivate variable.
600   /// \param VDAddr Address of the global variable \a VD.
601   /// \param Loc Location of threadprivate declaration.
602   /// \param PerformInit true if initialization expression is not constant.
603   virtual llvm::Function *
604   emitThreadPrivateVarDefinition(const VarDecl *VD, Address VDAddr,
605                                  SourceLocation Loc, bool PerformInit,
606                                  CodeGenFunction *CGF = nullptr);
607 
608   /// \brief Emit flush of the variables specified in 'omp flush' directive.
609   /// \param Vars List of variables to flush.
610   virtual void emitFlush(CodeGenFunction &CGF, ArrayRef<const Expr *> Vars,
611                          SourceLocation Loc);
612 
613   /// \brief Emit task region for the task directive. The task region is
614   /// emitted in several steps:
615   /// 1. Emit a call to kmp_task_t *__kmpc_omp_task_alloc(ident_t *, kmp_int32
616   /// gtid, kmp_int32 flags, size_t sizeof_kmp_task_t, size_t sizeof_shareds,
617   /// kmp_routine_entry_t *task_entry). Here task_entry is a pointer to the
618   /// function:
619   /// kmp_int32 .omp_task_entry.(kmp_int32 gtid, kmp_task_t *tt) {
620   ///   TaskFunction(gtid, tt->part_id, tt->shareds);
621   ///   return 0;
622   /// }
623   /// 2. Copy a list of shared variables to field shareds of the resulting
624   /// structure kmp_task_t returned by the previous call (if any).
625   /// 3. Copy a pointer to destructions function to field destructions of the
626   /// resulting structure kmp_task_t.
627   /// 4. Emit a call to kmp_int32 __kmpc_omp_task(ident_t *, kmp_int32 gtid,
628   /// kmp_task_t *new_task), where new_task is a resulting structure from
629   /// previous items.
630   /// \param D Current task directive.
631   /// \param Tied true if the task is tied (the task is tied to the thread that
632   /// can suspend its task region), false - untied (the task is not tied to any
633   /// thread).
634   /// \param Final Contains either constant bool value, or llvm::Value * of i1
635   /// type for final clause. If the value is true, the task forces all of its
636   /// child tasks to become final and included tasks.
637   /// \param TaskFunction An LLVM function with type void (*)(i32 /*gtid*/, i32
638   /// /*part_id*/, captured_struct */*__context*/);
639   /// \param SharedsTy A type which contains references the shared variables.
640   /// \param Shareds Context with the list of shared variables from the \p
641   /// TaskFunction.
642   /// \param IfCond Not a nullptr if 'if' clause was specified, nullptr
643   /// otherwise.
644   /// \param PrivateVars List of references to private variables for the task
645   /// directive.
646   /// \param PrivateCopies List of private copies for each private variable in
647   /// \p PrivateVars.
648   /// \param FirstprivateVars List of references to private variables for the
649   /// task directive.
650   /// \param FirstprivateCopies List of private copies for each private variable
651   /// in \p FirstprivateVars.
652   /// \param FirstprivateInits List of references to auto generated variables
653   /// used for initialization of a single array element. Used if firstprivate
654   /// variable is of array type.
655   /// \param Dependences List of dependences for the 'task' construct, including
656   /// original expression and dependency type.
657   virtual void emitTaskCall(
658       CodeGenFunction &CGF, SourceLocation Loc, const OMPExecutableDirective &D,
659       bool Tied, llvm::PointerIntPair<llvm::Value *, 1, bool> Final,
660       llvm::Value *TaskFunction, QualType SharedsTy, Address Shareds,
661       const Expr *IfCond, ArrayRef<const Expr *> PrivateVars,
662       ArrayRef<const Expr *> PrivateCopies,
663       ArrayRef<const Expr *> FirstprivateVars,
664       ArrayRef<const Expr *> FirstprivateCopies,
665       ArrayRef<const Expr *> FirstprivateInits,
666       ArrayRef<std::pair<OpenMPDependClauseKind, const Expr *>> Dependences);
667 
668   /// \brief Emit code for the directive that does not require outlining.
669   ///
670   /// \param InnermostKind Kind of innermost directive (for simple directives it
671   /// is a directive itself, for combined - its innermost directive).
672   /// \param CodeGen Code generation sequence for the \a D directive.
673   /// \param HasCancel true if region has inner cancel directive, false
674   /// otherwise.
675   virtual void emitInlinedDirective(CodeGenFunction &CGF,
676                                     OpenMPDirectiveKind InnermostKind,
677                                     const RegionCodeGenTy &CodeGen,
678                                     bool HasCancel = false);
679   /// \brief Emit a code for reduction clause. Next code should be emitted for
680   /// reduction:
681   /// \code
682   ///
683   /// static kmp_critical_name lock = { 0 };
684   ///
685   /// void reduce_func(void *lhs[<n>], void *rhs[<n>]) {
686   ///  ...
687   ///  *(Type<i>*)lhs[i] = RedOp<i>(*(Type<i>*)lhs[i], *(Type<i>*)rhs[i]);
688   ///  ...
689   /// }
690   ///
691   /// ...
692   /// void *RedList[<n>] = {&<RHSExprs>[0], ..., &<RHSExprs>[<n>-1]};
693   /// switch (__kmpc_reduce{_nowait}(<loc>, <gtid>, <n>, sizeof(RedList),
694   /// RedList, reduce_func, &<lock>)) {
695   /// case 1:
696   ///  ...
697   ///  <LHSExprs>[i] = RedOp<i>(*<LHSExprs>[i], *<RHSExprs>[i]);
698   ///  ...
699   /// __kmpc_end_reduce{_nowait}(<loc>, <gtid>, &<lock>);
700   /// break;
701   /// case 2:
702   ///  ...
703   ///  Atomic(<LHSExprs>[i] = RedOp<i>(*<LHSExprs>[i], *<RHSExprs>[i]));
704   ///  ...
705   /// break;
706   /// default:;
707   /// }
708   /// \endcode
709   ///
710   /// \param Privates List of private copies for original reduction arguments.
711   /// \param LHSExprs List of LHS in \a ReductionOps reduction operations.
712   /// \param RHSExprs List of RHS in \a ReductionOps reduction operations.
713   /// \param ReductionOps List of reduction operations in form 'LHS binop RHS'
714   /// or 'operator binop(LHS, RHS)'.
715   /// \param WithNowait true if parent directive has also nowait clause, false
716   /// otherwise.
717   virtual void emitReduction(CodeGenFunction &CGF, SourceLocation Loc,
718                              ArrayRef<const Expr *> Privates,
719                              ArrayRef<const Expr *> LHSExprs,
720                              ArrayRef<const Expr *> RHSExprs,
721                              ArrayRef<const Expr *> ReductionOps,
722                              bool WithNowait, bool SimpleReduction);
723 
724   /// \brief Emit code for 'taskwait' directive.
725   virtual void emitTaskwaitCall(CodeGenFunction &CGF, SourceLocation Loc);
726 
727   /// \brief Emit code for 'cancellation point' construct.
728   /// \param CancelRegion Region kind for which the cancellation point must be
729   /// emitted.
730   ///
731   virtual void emitCancellationPointCall(CodeGenFunction &CGF,
732                                          SourceLocation Loc,
733                                          OpenMPDirectiveKind CancelRegion);
734 
735   /// \brief Emit code for 'cancel' construct.
736   /// \param IfCond Condition in the associated 'if' clause, if it was
737   /// specified, nullptr otherwise.
738   /// \param CancelRegion Region kind for which the cancel must be emitted.
739   ///
740   virtual void emitCancelCall(CodeGenFunction &CGF, SourceLocation Loc,
741                               const Expr *IfCond,
742                               OpenMPDirectiveKind CancelRegion);
743 
744   /// \brief Emit outilined function for 'target' directive.
745   /// \param D Directive to emit.
746   /// \param CodeGen Code generation sequence for the \a D directive.
747   virtual llvm::Value *
748   emitTargetOutlinedFunction(const OMPExecutableDirective &D,
749                              const RegionCodeGenTy &CodeGen);
750 
751   /// \brief Emit the target offloading code associated with \a D. The emitted
752   /// code attempts offloading the execution to the device, an the event of
753   /// a failure it executes the host version outlined in \a OutlinedFn.
754   /// \param D Directive to emit.
755   /// \param OutlinedFn Host version of the code to be offloaded.
756   /// \param IfCond Expression evaluated in if clause associated with the target
757   /// directive, or null if no if clause is used.
758   /// \param Device Expression evaluated in device clause associated with the
759   /// target directive, or null if no device clause is used.
760   /// \param CapturedVars Values captured in the current region.
761   virtual void emitTargetCall(CodeGenFunction &CGF,
762                               const OMPExecutableDirective &D,
763                               llvm::Value *OutlinedFn, const Expr *IfCond,
764                               const Expr *Device,
765                               ArrayRef<llvm::Value *> CapturedVars);
766 };
767 
768 } // namespace CodeGen
769 } // namespace clang
770 
771 #endif
772