[OPENMP]Improve use of the global tid parameter.

If we can determined, that the global tid parameter can be used in the
function, better to use it rather than calling __kmpc_global_thread_num
function.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@375134 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 14 insertions, 9 deletions

diff --git a/lib/CodeGen/CGOpenMPRuntime.cpp b/lib/CodeGen/CGOpenMPRuntime.cpp
index 6a6659f906..8b853e8aa1 100644
--- a/lib/CodeGen/CGOpenMPRuntime.cpp
+++ b/lib/CodeGen/CGOpenMPRuntime.cpp
@@ -1697,18 +1697,23 @@ llvm::Value *CGOpenMPRuntime::getThreadID(CodeGenFunction &CGF,
       return ThreadID;
   }
   // If exceptions are enabled, do not use parameter to avoid possible crash.
-  if (!CGF.EHStack.requiresLandingPad() || !CGF.getLangOpts().Exceptions ||
-      !CGF.getLangOpts().CXXExceptions ||
-      CGF.Builder.GetInsertBlock() == CGF.AllocaInsertPt->getParent()) {
-    if (auto *OMPRegionInfo =
-            dyn_cast_or_null<CGOpenMPRegionInfo>(CGF.CapturedStmtInfo)) {
-      if (OMPRegionInfo->getThreadIDVariable()) {
-        // Check if this an outlined function with thread id passed as argument.
-        LValue LVal = OMPRegionInfo->getThreadIDVariableLValue(CGF);
+  if (auto *OMPRegionInfo =
+          dyn_cast_or_null<CGOpenMPRegionInfo>(CGF.CapturedStmtInfo)) {
+    if (OMPRegionInfo->getThreadIDVariable()) {
+      // Check if this an outlined function with thread id passed as argument.
+      LValue LVal = OMPRegionInfo->getThreadIDVariableLValue(CGF);
+      llvm::BasicBlock *TopBlock = CGF.AllocaInsertPt->getParent();
+      if (!CGF.EHStack.requiresLandingPad() || !CGF.getLangOpts().Exceptions ||
+          !CGF.getLangOpts().CXXExceptions ||
+          CGF.Builder.GetInsertBlock() == TopBlock ||
+          !isa<llvm::Instruction>(LVal.getPointer()) ||
+          cast<llvm::Instruction>(LVal.getPointer())->getParent() == TopBlock ||
+          cast<llvm::Instruction>(LVal.getPointer())->getParent() ==
+              CGF.Builder.GetInsertBlock()) {
         ThreadID = CGF.EmitLoadOfScalar(LVal, Loc);
         // If value loaded in entry block, cache it and use it everywhere in
         // function.
-        if (CGF.Builder.GetInsertBlock() == CGF.AllocaInsertPt->getParent()) {
+        if (CGF.Builder.GetInsertBlock() == TopBlock) {
           auto &Elem = OpenMPLocThreadIDMap.FindAndConstruct(CGF.CurFn);
           Elem.second.ThreadID = ThreadID;
         }