[OPENMP] Codegen for 'ordered' directive.

Add codegen for 'ordered' directive:

__kmpc_ordered(ident_t *, gtid);
<associated statement>;
__kmpc_end_ordered(ident_t *, gtid);
Also for 'for' directives with the dynamic scheduling and an 'ordered' clause added a call to '__kmpc_dispatch_fini_(4|8)[u]()' function after increment expression for loop control variable:

while(__kmpc_dispatch_next(&LB, &UB)) {
  idx = LB;
  while (idx <= UB) { BODY; ++idx;
    __kmpc_dispatch_fini_(4|8)[u](); // For ordered loops only.
  } // inner loop
}
Differential Revision: http://reviews.llvm.org/D9070

llvm-svn: 235496

4 files changed, 148 insertions, 32 deletions

diff --git a/clang/lib/CodeGen/CGOpenMPRuntime.cpp b/clang/lib/CodeGen/CGOpenMPRuntime.cpp
index 5988c785154..f7caee1bbc4 100644
--- a/clang/lib/CodeGen/CGOpenMPRuntime.cpp
+++ b/clang/lib/CodeGen/CGOpenMPRuntime.cpp
@@ -710,6 +710,22 @@ CGOpenMPRuntime::createRuntimeFunction(OpenMPRTLFunction Function) {
         CGM.CreateRuntimeFunction(FnTy, /*Name=*/"__kmpc_end_reduce_nowait");
     break;
   }
+  case OMPRTL__kmpc_ordered: {
+    // Build void __kmpc_ordered(ident_t *loc, kmp_int32 global_tid);
+    llvm::Type *TypeParams[] = {getIdentTyPointerTy(), CGM.Int32Ty};
+    llvm::FunctionType *FnTy =
+        llvm::FunctionType::get(CGM.VoidTy, TypeParams, /*isVarArg=*/false);
+    RTLFn = CGM.CreateRuntimeFunction(FnTy, "__kmpc_ordered");
+    break;
+  }
+  case OMPRTL__kmpc_end_ordered: {
+    // Build void __kmpc_ordered(ident_t *loc, kmp_int32 global_tid);
+    llvm::Type *TypeParams[] = {getIdentTyPointerTy(), CGM.Int32Ty};
+    llvm::FunctionType *FnTy =
+        llvm::FunctionType::get(CGM.VoidTy, TypeParams, /*isVarArg=*/false);
+    RTLFn = CGM.CreateRuntimeFunction(FnTy, "__kmpc_end_ordered");
+    break;
+  }
   }
   return RTLFn;
 }
@@ -762,6 +778,23 @@ llvm::Constant *CGOpenMPRuntime::createDispatchInitFunction(unsigned IVSize,
   return CGM.CreateRuntimeFunction(FnTy, Name);
 }
 
+llvm::Constant *CGOpenMPRuntime::createDispatchFiniFunction(unsigned IVSize,
+                                                            bool IVSigned) {
+  assert((IVSize == 32 || IVSize == 64) &&
+         "IV size is not compatible with the omp runtime");
+  auto Name =
+      IVSize == 32
+          ? (IVSigned ? "__kmpc_dispatch_fini_4" : "__kmpc_dispatch_fini_4u")
+          : (IVSigned ? "__kmpc_dispatch_fini_8" : "__kmpc_dispatch_fini_8u");
+  llvm::Type *TypeParams[] = {
+      getIdentTyPointerTy(), // loc
+      CGM.Int32Ty,           // tid
+  };
+  llvm::FunctionType *FnTy =
+      llvm::FunctionType::get(CGM.VoidTy, TypeParams, /*isVarArg=*/false);
+  return CGM.CreateRuntimeFunction(FnTy, Name);
+}
+
 llvm::Constant *CGOpenMPRuntime::createDispatchNextFunction(unsigned IVSize,
                                                             bool IVSigned) {
   assert((IVSize == 32 || IVSize == 64) &&
@@ -1246,6 +1279,25 @@ void CGOpenMPRuntime::emitSingleRegion(CodeGenFunction &CGF,
   }
 }
 
+void CGOpenMPRuntime::emitOrderedRegion(CodeGenFunction &CGF,
+                                        const RegionCodeGenTy &OrderedOpGen,
+                                        SourceLocation Loc) {
+  // __kmpc_ordered(ident_t *, gtid);
+  // OrderedOpGen();
+  // __kmpc_end_ordered(ident_t *, gtid);
+  // Prepare arguments and build a call to __kmpc_ordered
+  {
+    CodeGenFunction::RunCleanupsScope Scope(CGF);
+    llvm::Value *Args[] = {emitUpdateLocation(CGF, Loc), getThreadID(CGF, Loc)};
+    CGF.EmitRuntimeCall(createRuntimeFunction(OMPRTL__kmpc_ordered), Args);
+    // Build a call to __kmpc_end_ordered
+    CGF.EHStack.pushCleanup<CallEndCleanup>(
+        NormalAndEHCleanup, createRuntimeFunction(OMPRTL__kmpc_end_ordered),
+        llvm::makeArrayRef(Args));
+    emitInlinedDirective(CGF, OrderedOpGen);
+  }
+}
+
 void CGOpenMPRuntime::emitBarrierCall(CodeGenFunction &CGF, SourceLocation Loc,
                                       OpenMPDirectiveKind Kind) {
   // Build call __kmpc_cancel_barrier(loc, thread_id);
@@ -1378,12 +1430,8 @@ void CGOpenMPRuntime::emitForInit(CodeGenFunction &CGF, SourceLocation Loc,
   }
 }
 
-void CGOpenMPRuntime::emitForFinish(CodeGenFunction &CGF, SourceLocation Loc,
-                                    OpenMPScheduleClauseKind ScheduleKind) {
-  assert((ScheduleKind == OMPC_SCHEDULE_static ||
-          ScheduleKind == OMPC_SCHEDULE_unknown) &&
-         "Non-static schedule kinds are not yet implemented");
-  (void)ScheduleKind;
+void CGOpenMPRuntime::emitForStaticFinish(CodeGenFunction &CGF,
+                                          SourceLocation Loc) {
   // Call __kmpc_for_static_fini(ident_t *loc, kmp_int32 tid);
   llvm::Value *Args[] = {emitUpdateLocation(CGF, Loc, OMP_IDENT_KMPC),
                          getThreadID(CGF, Loc)};
@@ -1391,6 +1439,16 @@ void CGOpenMPRuntime::emitForFinish(CodeGenFunction &CGF, SourceLocation Loc,
                       Args);
 }
 
+void CGOpenMPRuntime::emitForOrderedDynamicIterationEnd(CodeGenFunction &CGF,
+                                                        SourceLocation Loc,
+                                                        unsigned IVSize,
+                                                        bool IVSigned) {
+  // Call __kmpc_for_dynamic_fini_(4|8)[u](ident_t *loc, kmp_int32 tid);
+  llvm::Value *Args[] = {emitUpdateLocation(CGF, Loc, OMP_IDENT_KMPC),
+                         getThreadID(CGF, Loc)};
+  CGF.EmitRuntimeCall(createDispatchFiniFunction(IVSize, IVSigned), Args);
+}
+
 llvm::Value *CGOpenMPRuntime::emitForNext(CodeGenFunction &CGF,
                                           SourceLocation Loc, unsigned IVSize,
                                           bool IVSigned, llvm::Value *IL,
diff --git a/clang/lib/CodeGen/CGOpenMPRuntime.h b/clang/lib/CodeGen/CGOpenMPRuntime.h
index fa599308223..f3c4379560a 100644
--- a/clang/lib/CodeGen/CGOpenMPRuntime.h
+++ b/clang/lib/CodeGen/CGOpenMPRuntime.h
@@ -118,6 +118,10 @@ private:
     // Call to void __kmpc_end_reduce_nowait(ident_t *loc, kmp_int32 global_tid,
     // kmp_critical_name *lck);
     OMPRTL__kmpc_end_reduce_nowait,
+    // Call to void __kmpc_ordered(ident_t *loc, kmp_int32 global_tid);
+    OMPRTL__kmpc_ordered,
+    // Call to void __kmpc_end_ordered(ident_t *loc, kmp_int32 global_tid);
+    OMPRTL__kmpc_end_ordered,
   };
 
   /// \brief Values for bit flags used in the ident_t to describe the fields.
@@ -252,6 +256,10 @@ private:
   /// size \a IVSize and sign \a IVSigned.
   llvm::Constant *createDispatchNextFunction(unsigned IVSize, bool IVSigned);
 
+  /// \brief Returns __kmpc_dispatch_fini_* runtime function for the specified
+  /// size \a IVSize and sign \a IVSigned.
+  llvm::Constant *createDispatchFiniFunction(unsigned IVSize, bool IVSigned);
+
   /// \brief If the specified mangled name is not in the module, create and
   /// return threadprivate cache object. This object is a pointer's worth of
   /// storage that's reserved for use by the OpenMP runtime.
@@ -378,6 +386,13 @@ public:
                                 ArrayRef<const Expr *> SrcExprs,
                                 ArrayRef<const Expr *> AssignmentOps);
 
+  /// \brief Emit an ordered region.
+  /// \param OrderedOpGen Generator for the statement associated with the given
+  /// critical region.
+  virtual void emitOrderedRegion(CodeGenFunction &CGF,
+                                 const RegionCodeGenTy &OrderedOpGen,
+                                 SourceLocation Loc);
+
   /// \brief Emit an implicit/explicit barrier for OpenMP threads.
   /// \param Kind Directive for which this implicit barrier call must be
   /// generated. Must be OMPD_barrier for explicit barrier generation.
@@ -429,14 +444,25 @@ public:
                            llvm::Value *Chunk = nullptr);
 
   /// \brief Call the appropriate runtime routine to notify that we finished
+  /// iteration of the ordered loop with the dynamic scheduling.
+  ///
+  /// \param CGF Reference to current CodeGenFunction.
+  /// \param Loc Clang source location.
+  /// \param IVSize Size of the iteration variable in bits.
+  /// \param IVSigned Sign of the interation variable.
+  ///
+  virtual void emitForOrderedDynamicIterationEnd(CodeGenFunction &CGF,
+                                                 SourceLocation Loc,
+                                                 unsigned IVSize,
+                                                 bool IVSigned);
+
+  /// \brief Call the appropriate runtime routine to notify that we finished
   /// all the work with current loop.
   ///
   /// \param CGF Reference to current CodeGenFunction.
   /// \param Loc Clang source location.
-  /// \param ScheduleKind Schedule kind, specified by the 'schedule' clause.
   ///
-  virtual void emitForFinish(CodeGenFunction &CGF, SourceLocation Loc,
-                             OpenMPScheduleClauseKind ScheduleKind);
+  virtual void emitForStaticFinish(CodeGenFunction &CGF, SourceLocation Loc);
 
   /// Call __kmpc_dispatch_next(
   ///          ident_t *loc, kmp_int32 tid, kmp_int32 *p_lastiter,
diff --git a/clang/lib/CodeGen/CGStmtOpenMP.cpp b/clang/lib/CodeGen/CGStmtOpenMP.cpp
index 1541ba687cf..9451802ecef 100644
--- a/clang/lib/CodeGen/CGStmtOpenMP.cpp
+++ b/clang/lib/CodeGen/CGStmtOpenMP.cpp
@@ -576,7 +576,8 @@ void CodeGenFunction::EmitOMPLoopBody(const OMPLoopDirective &S,
 void CodeGenFunction::EmitOMPInnerLoop(
     const Stmt &S, bool RequiresCleanup, const Expr *LoopCond,
     const Expr *IncExpr,
-    const llvm::function_ref<void(CodeGenFunction &)> &BodyGen) {
+    const llvm::function_ref<void(CodeGenFunction &)> &BodyGen,
+    const llvm::function_ref<void(CodeGenFunction &)> &PostIncGen) {
   auto LoopExit = getJumpDestInCurrentScope("omp.inner.for.end");
   auto Cnt = getPGORegionCounter(&S);
 
@@ -612,6 +613,7 @@ void CodeGenFunction::EmitOMPInnerLoop(
   // Emit "IV = IV + 1" and a back-edge to the condition block.
   EmitBlock(Continue.getBlock());
   EmitIgnoredExpr(IncExpr);
+  PostIncGen(*this);
   BreakContinueStack.pop_back();
   EmitBranch(CondBlock);
   LoopStack.pop();
@@ -799,7 +801,8 @@ void CodeGenFunction::EmitOMPSimdDirective(const OMPSimdDirective &S) {
                              [&S](CodeGenFunction &CGF) {
                                CGF.EmitOMPLoopBody(S);
                                CGF.EmitStopPoint(&S);
-                             });
+                             },
+                             [](CodeGenFunction &) {});
         CGF.EmitOMPLoopBody(S, /* SeparateIter */ true);
       }
       CGF.EmitOMPSimdFinal(S);
@@ -818,7 +821,8 @@ void CodeGenFunction::EmitOMPSimdDirective(const OMPSimdDirective &S) {
                              [&S](CodeGenFunction &CGF) {
                                CGF.EmitOMPLoopBody(S);
                                CGF.EmitStopPoint(&S);
-                             });
+                             },
+                             [](CodeGenFunction &) {});
       }
       CGF.EmitOMPSimdFinal(S);
     }
@@ -873,7 +877,9 @@ void CodeGenFunction::EmitOMPForOuterLoop(OpenMPScheduleClauseKind ScheduleKind,
   //
   // while(__kmpc_dispatch_next(&LB, &UB)) {
   //   idx = LB;
-  //   while (idx <= UB) { BODY; ++idx; } // inner loop
+  //   while (idx <= UB) { BODY; ++idx;
+  //   __kmpc_dispatch_fini_(4|8)[u](); // For ordered loops only.
+  //   } // inner loop
   // }
   //
   // OpenMP [2.7.1, Loop Construct, Description, table 2-1]
@@ -940,12 +946,22 @@ void CodeGenFunction::EmitOMPForOuterLoop(OpenMPScheduleClauseKind ScheduleKind,
   auto Continue = getJumpDestInCurrentScope("omp.dispatch.inc");
   BreakContinueStack.push_back(BreakContinue(LoopExit, Continue));
 
-  EmitOMPInnerLoop(S, LoopScope.requiresCleanups(),
-                   S.getCond(/*SeparateIter=*/false), S.getInc(),
-                   [&S](CodeGenFunction &CGF) {
-                     CGF.EmitOMPLoopBody(S);
-                     CGF.EmitStopPoint(&S);
-                   });
+  bool DynamicWithOrderedClause =
+      Dynamic && S.getSingleClause(OMPC_ordered) != nullptr;
+  SourceLocation Loc = S.getLocStart();
+  EmitOMPInnerLoop(
+      S, LoopScope.requiresCleanups(), S.getCond(/*SeparateIter=*/false),
+      S.getInc(),
+      [&S](CodeGenFunction &CGF) {
+        CGF.EmitOMPLoopBody(S);
+        CGF.EmitStopPoint(&S);
+      },
+      [DynamicWithOrderedClause, IVSize, IVSigned, Loc](CodeGenFunction &CGF) {
+        if (DynamicWithOrderedClause) {
+          CGF.CGM.getOpenMPRuntime().emitForOrderedDynamicIterationEnd(
+              CGF, Loc, IVSize, IVSigned);
+        }
+      });
 
   EmitBlock(Continue.getBlock());
   BreakContinueStack.pop_back();
@@ -961,9 +977,8 @@ void CodeGenFunction::EmitOMPForOuterLoop(OpenMPScheduleClauseKind ScheduleKind,
   EmitBlock(LoopExit.getBlock());
 
   // Tell the runtime we are done.
-  // FIXME: Also call fini for ordered loops with dynamic scheduling.
   if (!Dynamic)
-    RT.emitForFinish(*this, S.getLocStart(), ScheduleKind);
+    RT.emitForStaticFinish(*this, S.getLocEnd());
 }
 
 /// \brief Emit a helper variable and return corresponding lvalue.
@@ -1058,9 +1073,10 @@ bool CodeGenFunction::EmitOMPWorksharingLoop(const OMPLoopDirective &S) {
                          [&S](CodeGenFunction &CGF) {
                            CGF.EmitOMPLoopBody(S);
                            CGF.EmitStopPoint(&S);
-                         });
+                         },
+                         [](CodeGenFunction &) {});
         // Tell the runtime we are done.
-        RT.emitForFinish(*this, S.getLocStart(), ScheduleKind);
+        RT.emitForStaticFinish(*this, S.getLocStart());
       } else {
         // Emit the outer loop, which requests its work chunk [LB..UB] from
         // runtime and runs the inner loop to process it.
@@ -1177,10 +1193,10 @@ static OpenMPDirectiveKind emitSections(CodeGenFunction &CGF,
       // IV = LB;
       CGF.EmitStoreOfScalar(CGF.EmitLoadOfScalar(LB, S.getLocStart()), IV);
       // while (idx <= UB) { BODY; ++idx; }
-      CGF.EmitOMPInnerLoop(S, /*RequiresCleanup=*/false, &Cond, &Inc, BodyGen);
+      CGF.EmitOMPInnerLoop(S, /*RequiresCleanup=*/false, &Cond, &Inc, BodyGen,
+                           [](CodeGenFunction &) {});
       // Tell the runtime we are done.
-      CGF.CGM.getOpenMPRuntime().emitForFinish(CGF, S.getLocStart(),
-                                               OMPC_SCHEDULE_static);
+      CGF.CGM.getOpenMPRuntime().emitForStaticFinish(CGF, S.getLocStart());
     };
 
     CGF.CGM.getOpenMPRuntime().emitInlinedDirective(CGF, CodeGen);
@@ -1372,8 +1388,13 @@ void CodeGenFunction::EmitOMPFlushDirective(const OMPFlushDirective &S) {
   }(), S.getLocStart());
 }
 
-void CodeGenFunction::EmitOMPOrderedDirective(const OMPOrderedDirective &) {
-  llvm_unreachable("CodeGen for 'omp ordered' is not supported yet.");
+void CodeGenFunction::EmitOMPOrderedDirective(const OMPOrderedDirective &S) {
+  LexicalScope Scope(*this, S.getSourceRange());
+  auto &&CodeGen = [&S](CodeGenFunction &CGF) {
+    CGF.EmitStmt(cast<CapturedStmt>(S.getAssociatedStmt())->getCapturedStmt());
+    CGF.EnsureInsertPoint();
+  };
+  CGM.getOpenMPRuntime().emitOrderedRegion(*this, CodeGen, S.getLocStart());
 }
 
 static llvm::Value *convertToScalarValue(CodeGenFunction &CGF, RValue Val,
diff --git a/clang/lib/CodeGen/CodeGenFunction.h b/clang/lib/CodeGen/CodeGenFunction.h
index 4e7a7e2f5a6..efbe07c1a05 100644
--- a/clang/lib/CodeGen/CodeGenFunction.h
+++ b/clang/lib/CodeGen/CodeGenFunction.h
@@ -2139,10 +2139,21 @@ public:
   void EmitOMPTargetDirective(const OMPTargetDirective &S);
   void EmitOMPTeamsDirective(const OMPTeamsDirective &S);
 
-  void
-  EmitOMPInnerLoop(const Stmt &S, bool RequiresCleanup, const Expr *LoopCond,
-                   const Expr *IncExpr,
-                   const llvm::function_ref<void(CodeGenFunction &)> &BodyGen);
+  /// \brief Emit inner loop of the worksharing/simd construct.
+  ///
+  /// \param S Directive, for which the inner loop must be emitted.
+  /// \param RequiresCleanup true, if directive has some associated private
+  /// variables.
+  /// \param LoopCond Bollean condition for loop continuation.
+  /// \param IncExpr Increment expression for loop control variable.
+  /// \param BodyGen Generator for the inner body of the inner loop.
+  /// \param PostIncGen Genrator for post-increment code (required for ordered
+  /// loop directvies).
+  void EmitOMPInnerLoop(
+      const Stmt &S, bool RequiresCleanup, const Expr *LoopCond,
+      const Expr *IncExpr,
+      const llvm::function_ref<void(CodeGenFunction &)> &BodyGen,
+      const llvm::function_ref<void(CodeGenFunction &)> &PostIncGen);
 
 private: