LPPassManager. Implement preparePassManager() hook.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@34975 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Analysis/LoopPass.cpp b/lib/Analysis/LoopPass.cpp
index 8d613b0..de062ba 100644
--- a/lib/Analysis/LoopPass.cpp
+++ b/lib/Analysis/LoopPass.cpp
@@ -129,6 +129,31 @@
//===----------------------------------------------------------------------===//
// LoopPass
+// Check if this pass is suitable for the current LPPassManager, if
+// available. This pass P is not suitable for a LPPassManager if P
+// is not preserving higher level analysis info used by other
+// LPPassManager passes. In such case, pop LPPassManager from the
+// stack. This will force assignPassManager() to create new
+// LPPassManger as expected.
+void LoopPass::preparePassManager(PMStack &PMS) {
+
+ // Find LPPassManager
+ while (!PMS.empty()) {
+ if (PMS.top()->getPassManagerType() > PMT_LoopPassManager)
+ PMS.pop();
+ else;
+ break;
+ }
+
+ LPPassManager *LPPM = dynamic_cast<LPPassManager *>(PMS.top());
+
+ // If this pass is destroying high level information that is used
+ // by other passes that are managed by LPM then do not insert
+ // this pass in current LPM. Use new LPPassManager.
+ if (LPPM && !LPPM->preserveHigherLevelAnalysis(this))
+ PMS.pop();
+}
+
/// Assign pass manager to manage this pass.
void LoopPass::assignPassManager(PMStack &PMS,
PassManagerType PreferredType) {