[OPENMP]Improve detection of number of teams, threads in target

regions.

Added more complex analysis for number of teams and number of threads in
the target regions, also merged related common code between CGOpenMPRuntime
and CGOpenMPRuntimeNVPTX classes.

llvm-svn: 358126

1 files changed, 23 insertions, 71 deletions

diff --git a/clang/lib/CodeGen/CGOpenMPRuntimeNVPTX.cpp b/clang/lib/CodeGen/CGOpenMPRuntimeNVPTX.cpp
index 632bca6ff9d..5a8f50bf316 100644
--- a/clang/lib/CodeGen/CGOpenMPRuntimeNVPTX.cpp
+++ b/clang/lib/CodeGen/CGOpenMPRuntimeNVPTX.cpp
@@ -714,61 +714,6 @@ getDataSharingMode(CodeGenModule &CGM) {
                                           : CGOpenMPRuntimeNVPTX::Generic;
 }
 
-/// Checks if the expression is constant or does not have non-trivial function
-/// calls.
-static bool isTrivial(ASTContext &Ctx, const Expr * E) {
-  // We can skip constant expressions.
-  // We can skip expressions with trivial calls or simple expressions.
-  return (E->isEvaluatable(Ctx, Expr::SE_AllowUndefinedBehavior) ||
-          !E->hasNonTrivialCall(Ctx)) &&
-         !E->HasSideEffects(Ctx, /*IncludePossibleEffects=*/true);
-}
-
-/// Checks if the \p Body is the \a CompoundStmt and returns its child statement
-/// iff there is only one that is not evaluatable at the compile time.
-static const Stmt *getSingleCompoundChild(ASTContext &Ctx, const Stmt *Body) {
-  if (const auto *C = dyn_cast<CompoundStmt>(Body)) {
-    const Stmt *Child = nullptr;
-    for (const Stmt *S : C->body()) {
-      if (const auto *E = dyn_cast<Expr>(S)) {
-        if (isTrivial(Ctx, E))
-          continue;
-      }
-      // Some of the statements can be ignored.
-      if (isa<AsmStmt>(S) || isa<NullStmt>(S) || isa<OMPFlushDirective>(S) ||
-          isa<OMPBarrierDirective>(S) || isa<OMPTaskyieldDirective>(S))
-        continue;
-      // Analyze declarations.
-      if (const auto *DS = dyn_cast<DeclStmt>(S)) {
-        if (llvm::all_of(DS->decls(), [&Ctx](const Decl *D) {
-              if (isa<EmptyDecl>(D) || isa<DeclContext>(D) ||
-                  isa<TypeDecl>(D) || isa<PragmaCommentDecl>(D) ||
-                  isa<PragmaDetectMismatchDecl>(D) || isa<UsingDecl>(D) ||
-                  isa<UsingDirectiveDecl>(D) ||
-                  isa<OMPDeclareReductionDecl>(D) ||
-                  isa<OMPThreadPrivateDecl>(D) || isa<OMPAllocateDecl>(D))
-                return true;
-              const auto *VD = dyn_cast<VarDecl>(D);
-              if (!VD)
-                return false;
-              return VD->isConstexpr() ||
-                     ((VD->getType().isTrivialType(Ctx) ||
-                       VD->getType()->isReferenceType()) &&
-                      (!VD->hasInit() || isTrivial(Ctx, VD->getInit())));
-            }))
-          continue;
-      }
-      // Found multiple children - cannot get the one child only.
-      if (Child)
-        return Body;
-      Child = S;
-    }
-    if (Child)
-      return Child;
-  }
-  return Body;
-}
-
 /// Check if the parallel directive has an 'if' clause with non-constant or
 /// false condition. Also, check if the number of threads is strictly specified
 /// and run those directives in non-SPMD mode.
@@ -794,9 +739,10 @@ static bool hasNestedSPMDDirective(ASTContext &Ctx,
   const auto *CS = D.getInnermostCapturedStmt();
   const auto *Body =
       CS->getCapturedStmt()->IgnoreContainers(/*IgnoreCaptured=*/true);
-  const Stmt *ChildStmt = getSingleCompoundChild(Ctx, Body);
+  const Stmt *ChildStmt = CGOpenMPRuntime::getSingleCompoundChild(Ctx, Body);
 
-  if (const auto *NestedDir = dyn_cast<OMPExecutableDirective>(ChildStmt)) {
+  if (const auto *NestedDir =
+          dyn_cast_or_null<OMPExecutableDirective>(ChildStmt)) {
     OpenMPDirectiveKind DKind = NestedDir->getDirectiveKind();
     switch (D.getDirectiveKind()) {
     case OMPD_target:
@@ -808,8 +754,9 @@ static bool hasNestedSPMDDirective(ASTContext &Ctx,
             /*IgnoreCaptured=*/true);
         if (!Body)
           return false;
-        ChildStmt = getSingleCompoundChild(Ctx, Body);
-        if (const auto *NND = dyn_cast<OMPExecutableDirective>(ChildStmt)) {
+        ChildStmt = CGOpenMPRuntime::getSingleCompoundChild(Ctx, Body);
+        if (const auto *NND =
+                dyn_cast_or_null<OMPExecutableDirective>(ChildStmt)) {
           DKind = NND->getDirectiveKind();
           if (isOpenMPParallelDirective(DKind) &&
               !hasParallelIfNumThreadsClause(Ctx, *NND))
@@ -971,9 +918,10 @@ static bool hasNestedLightweightDirective(ASTContext &Ctx,
   const auto *CS = D.getInnermostCapturedStmt();
   const auto *Body =
       CS->getCapturedStmt()->IgnoreContainers(/*IgnoreCaptured=*/true);
-  const Stmt *ChildStmt = getSingleCompoundChild(Ctx, Body);
+  const Stmt *ChildStmt = CGOpenMPRuntime::getSingleCompoundChild(Ctx, Body);
 
-  if (const auto *NestedDir = dyn_cast<OMPExecutableDirective>(ChildStmt)) {
+  if (const auto *NestedDir =
+          dyn_cast_or_null<OMPExecutableDirective>(ChildStmt)) {
     OpenMPDirectiveKind DKind = NestedDir->getDirectiveKind();
     switch (D.getDirectiveKind()) {
     case OMPD_target:
@@ -986,8 +934,9 @@ static bool hasNestedLightweightDirective(ASTContext &Ctx,
             /*IgnoreCaptured=*/true);
         if (!Body)
           return false;
-        ChildStmt = getSingleCompoundChild(Ctx, Body);
-        if (const auto *NND = dyn_cast<OMPExecutableDirective>(ChildStmt)) {
+        ChildStmt = CGOpenMPRuntime::getSingleCompoundChild(Ctx, Body);
+        if (const auto *NND =
+                dyn_cast_or_null<OMPExecutableDirective>(ChildStmt)) {
           DKind = NND->getDirectiveKind();
           if (isOpenMPWorksharingDirective(DKind) &&
               isOpenMPLoopDirective(DKind) && hasStaticScheduling(*NND))
@@ -998,8 +947,9 @@ static bool hasNestedLightweightDirective(ASTContext &Ctx,
             /*IgnoreCaptured=*/true);
         if (!Body)
           return false;
-        ChildStmt = getSingleCompoundChild(Ctx, Body);
-        if (const auto *NND = dyn_cast<OMPExecutableDirective>(ChildStmt)) {
+        ChildStmt = CGOpenMPRuntime::getSingleCompoundChild(Ctx, Body);
+        if (const auto *NND =
+                dyn_cast_or_null<OMPExecutableDirective>(ChildStmt)) {
           DKind = NND->getDirectiveKind();
           if (isOpenMPParallelDirective(DKind) &&
               isOpenMPWorksharingDirective(DKind) &&
@@ -1010,8 +960,9 @@ static bool hasNestedLightweightDirective(ASTContext &Ctx,
                 /*IgnoreCaptured=*/true);
             if (!Body)
               return false;
-            ChildStmt = getSingleCompoundChild(Ctx, Body);
-            if (const auto *NND = dyn_cast<OMPExecutableDirective>(ChildStmt)) {
+            ChildStmt = CGOpenMPRuntime::getSingleCompoundChild(Ctx, Body);
+            if (const auto *NND =
+                    dyn_cast_or_null<OMPExecutableDirective>(ChildStmt)) {
               DKind = NND->getDirectiveKind();
               if (isOpenMPWorksharingDirective(DKind) &&
                   isOpenMPLoopDirective(DKind) && hasStaticScheduling(*NND))
@@ -1031,8 +982,9 @@ static bool hasNestedLightweightDirective(ASTContext &Ctx,
             /*IgnoreCaptured=*/true);
         if (!Body)
           return false;
-        ChildStmt = getSingleCompoundChild(Ctx, Body);
-        if (const auto *NND = dyn_cast<OMPExecutableDirective>(ChildStmt)) {
+        ChildStmt = CGOpenMPRuntime::getSingleCompoundChild(Ctx, Body);
+        if (const auto *NND =
+                dyn_cast_or_null<OMPExecutableDirective>(ChildStmt)) {
           DKind = NND->getDirectiveKind();
           if (isOpenMPWorksharingDirective(DKind) &&
               isOpenMPLoopDirective(DKind) && hasStaticScheduling(*NND))
@@ -2014,11 +1966,11 @@ getDistributeLastprivateVars(ASTContext &Ctx, const OMPExecutableDirective &D,
          "expected teams directive.");
   const OMPExecutableDirective *Dir = &D;
   if (!isOpenMPDistributeDirective(D.getDirectiveKind())) {
-    if (const Stmt *S = getSingleCompoundChild(
+    if (const Stmt *S = CGOpenMPRuntime::getSingleCompoundChild(
             Ctx,
             D.getInnermostCapturedStmt()->getCapturedStmt()->IgnoreContainers(
                 /*IgnoreCaptured=*/true))) {
-      Dir = dyn_cast<OMPExecutableDirective>(S);
+      Dir = dyn_cast_or_null<OMPExecutableDirective>(S);
       if (Dir && !isOpenMPDistributeDirective(Dir->getDirectiveKind()))
         Dir = nullptr;
     }