Revert "Revert r234581, it might have caused a few miscompiles in Chromium."

This reverts commit r234700.  It turns out that the lifetime markers
were not the cause of Chromium failing but a bug which was uncovered by
optimizations exposed by the markers.

llvm-svn: 235553

1 files changed, 8 insertions, 1 deletions

diff --git a/clang/lib/CodeGen/CGCleanup.h b/clang/lib/CodeGen/CGCleanup.h
index 5f94aec4978..81c64123dfd 100644
--- a/clang/lib/CodeGen/CGCleanup.h
+++ b/clang/lib/CodeGen/CGCleanup.h
@@ -62,6 +62,9 @@ protected:
     /// Whether this cleanup is currently active.
     unsigned IsActive : 1;
 
+    /// Whether this cleanup is a lifetime marker
+    unsigned IsLifetimeMarker : 1;
+
     /// Whether the normal cleanup should test the activation flag.
     unsigned TestFlagInNormalCleanup : 1;
 
@@ -75,7 +78,7 @@ protected:
     /// The number of fixups required by enclosing scopes (not including
     /// this one).  If this is the top cleanup scope, all the fixups
     /// from this index onwards belong to this scope.
-    unsigned FixupDepth : 32 - 17 - NumCommonBits; // currently 13    
+    unsigned FixupDepth : 32 - 18 - NumCommonBits; // currently 13
   };
 
   class FilterBitFields {
@@ -272,6 +275,7 @@ public:
     CleanupBits.IsNormalCleanup = isNormal;
     CleanupBits.IsEHCleanup = isEH;
     CleanupBits.IsActive = isActive;
+    CleanupBits.IsLifetimeMarker = false;
     CleanupBits.TestFlagInNormalCleanup = false;
     CleanupBits.TestFlagInEHCleanup = false;
     CleanupBits.CleanupSize = cleanupSize;
@@ -295,6 +299,9 @@ public:
   bool isActive() const { return CleanupBits.IsActive; }
   void setActive(bool A) { CleanupBits.IsActive = A; }
 
+  bool isLifetimeMarker() const { return CleanupBits.IsLifetimeMarker; }
+  void setLifetimeMarker() { CleanupBits.IsLifetimeMarker = true; }
+
   llvm::AllocaInst *getActiveFlag() const { return ActiveFlag; }
   void setActiveFlag(llvm::AllocaInst *Var) { ActiveFlag = Var; }