Reapply "[OpenMP][IRBuilder] Perform finalization (incl. outlining) late"

Reapply 8a56d64d7620b3764f10f03f3a1e307fcdd72c2f with minor fixes.

The problem was that cancellation can cause new edges to the parallel
region exit block which is not outlined. The CodeExtractor will encode
the information which "exit" was taken as a return value. The fix is to
ensure we do not return any value from the outlined function, to prevent
control to value conversion we ensure a single exit block for the
outlined region.

This reverts commit 3aac953afa34885a72df96f2b703b65f85cbb149.

1 files changed, 9 insertions, 0 deletions

diff --git a/clang/lib/CodeGen/CodeGenFunction.cpp b/clang/lib/CodeGen/CodeGenFunction.cpp
index b7506b5..4798de0 100644
--- a/clang/lib/CodeGen/CodeGenFunction.cpp
+++ b/clang/lib/CodeGen/CodeGenFunction.cpp
@@ -32,6 +32,7 @@
 #include "clang/Basic/TargetInfo.h"
 #include "clang/CodeGen/CGFunctionInfo.h"
 #include "clang/Frontend/FrontendDiagnostic.h"
+#include "llvm/Frontend/OpenMP/OMPIRBuilder.h"
 #include "llvm/IR/DataLayout.h"
 #include "llvm/IR/Dominators.h"
 #include "llvm/IR/FPEnv.h"
@@ -104,6 +105,14 @@ CodeGenFunction::~CodeGenFunction() {
 
   if (getLangOpts().OpenMP && CurFn)
     CGM.getOpenMPRuntime().functionFinished(*this);
+
+  // If we have an OpenMPIRBuilder we want to finalize functions (incl.
+  // outlining etc) at some point. Doing it once the function codegen is done
+  // seems to be a reasonable spot. We do it here, as opposed to the deletion
+  // time of the CodeGenModule, because we have to ensure the IR has not yet
+  // been "emitted" to the outside, thus, modifications are still sensible.
+  if (llvm::OpenMPIRBuilder *OMPBuilder = CGM.getOpenMPIRBuilder())
+    OMPBuilder->finalize();
 }
 
 // Map the LangOption for rounding mode into