[OpenMP] Basic support for a parallel directive in a target region on an NVPTX device

Summary:

This patch introduces support for the execution of parallel constructs in a target
region on the NVPTX device.  Parallel regions must be in the lexical scope of the
target directive.

The master thread in the master warp signals parallel work for worker threads in worker
warps on encountering a parallel region.

Note: The patch does not yet support capture of arguments in a parallel region so
the test cases are simple.

Reviewers: ABataev
Differential Revision: https://reviews.llvm.org/D28145

llvm-svn: 291565

1 files changed, 29 insertions, 13 deletions

diff --git a/clang/lib/CodeGen/CGOpenMPRuntime.h b/clang/lib/CodeGen/CGOpenMPRuntime.h
index 9a784dff0ae..61ddc702ed2 100644
--- a/clang/lib/CodeGen/CGOpenMPRuntime.h
+++ b/clang/lib/CodeGen/CGOpenMPRuntime.h
@@ -130,6 +130,35 @@ protected:
                                                 bool IsOffloadEntry,
                                                 const RegionCodeGenTy &CodeGen);
 
+  /// \brief Emits code for OpenMP 'if' clause using specified \a CodeGen
+  /// function. Here is the logic:
+  /// if (Cond) {
+  ///   ThenGen();
+  /// } else {
+  ///   ElseGen();
+  /// }
+  void emitOMPIfClause(CodeGenFunction &CGF, const Expr *Cond,
+                       const RegionCodeGenTy &ThenGen,
+                       const RegionCodeGenTy &ElseGen);
+
+  /// \brief Emits object of ident_t type with info for source location.
+  /// \param Flags Flags for OpenMP location.
+  ///
+  llvm::Value *emitUpdateLocation(CodeGenFunction &CGF, SourceLocation Loc,
+                                  unsigned Flags = 0);
+
+  /// \brief Returns pointer to ident_t type.
+  llvm::Type *getIdentTyPointerTy();
+
+  /// \brief Gets thread id value for the current thread.
+  ///
+  llvm::Value *getThreadID(CodeGenFunction &CGF, SourceLocation Loc);
+
+  /// \brief Get the function name of an outlined region.
+  //  The name can be customized depending on the target.
+  //
+  virtual StringRef getOutlinedHelperName() const { return ".omp_outlined."; }
+
 private:
   /// \brief Default const ident_t object used for initialization of all other
   /// ident_t objects.
@@ -388,15 +417,6 @@ private:
   /// \brief Build type kmp_routine_entry_t (if not built yet).
   void emitKmpRoutineEntryT(QualType KmpInt32Ty);
 
-  /// \brief Emits object of ident_t type with info for source location.
-  /// \param Flags Flags for OpenMP location.
-  ///
-  llvm::Value *emitUpdateLocation(CodeGenFunction &CGF, SourceLocation Loc,
-                                  unsigned Flags = 0);
-
-  /// \brief Returns pointer to ident_t type.
-  llvm::Type *getIdentTyPointerTy();
-
   /// \brief Returns pointer to kmpc_micro type.
   llvm::Type *getKmpc_MicroPointerTy();
 
@@ -432,10 +452,6 @@ private:
   /// stored.
   virtual Address emitThreadIDAddress(CodeGenFunction &CGF, SourceLocation Loc);
 
-  /// \brief Gets thread id value for the current thread.
-  ///
-  llvm::Value *getThreadID(CodeGenFunction &CGF, SourceLocation Loc);
-
   /// \brief 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.