Vendor import of llvm trunk r154661:

http://llvm.org/svn/llvm-project/llvm/trunk@r154661

1 files changed, 32 insertions, 2 deletions

diff --git a/include/llvm/Analysis/CaptureTracking.h b/include/llvm/Analysis/CaptureTracking.h
index b3390f4..9b5e842 100644
--- a/include/llvm/Analysis/CaptureTracking.h
+++ b/include/llvm/Analysis/CaptureTracking.h
@@ -14,9 +14,12 @@
 #ifndef LLVM_ANALYSIS_CAPTURETRACKING_H
 #define LLVM_ANALYSIS_CAPTURETRACKING_H
 
-namespace llvm {
-  class Value;
+#include "llvm/Constants.h"
+#include "llvm/Instructions.h"
+#include "llvm/Analysis/AliasAnalysis.h"
+#include "llvm/Support/CallSite.h"
 
+namespace llvm {
   /// PointerMayBeCaptured - Return true if this pointer value may be captured
   /// by the enclosing function (which is required to exist).  This routine can
   /// be expensive, so consider caching the results.  The boolean ReturnCaptures
@@ -28,6 +31,33 @@ namespace llvm {
                             bool ReturnCaptures,
                             bool StoreCaptures);
 
+  /// This callback is used in conjunction with PointerMayBeCaptured. In
+  /// addition to the interface here, you'll need to provide your own getters
+  /// to see whether anything was captured.
+  struct CaptureTracker {
+    virtual ~CaptureTracker();
+
+    /// tooManyUses - The depth of traversal has breached a limit. There may be
+    /// capturing instructions that will not be passed into captured().
+    virtual void tooManyUses() = 0;
+
+    /// shouldExplore - This is the use of a value derived from the pointer.
+    /// To prune the search (ie., assume that none of its users could possibly
+    /// capture) return false. To search it, return true.
+    ///
+    /// U->getUser() is always an Instruction.
+    virtual bool shouldExplore(Use *U) = 0;
+
+    /// captured - Information about the pointer was captured by the user of
+    /// use U. Return true to stop the traversal or false to continue looking
+    /// for more capturing instructions.
+    virtual bool captured(Use *U) = 0;
+  };
+
+  /// PointerMayBeCaptured - Visit the value and the values derived from it and
+  /// find values which appear to be capturing the pointer value. This feeds
+  /// results into and is controlled by the CaptureTracker object.
+  void PointerMayBeCaptured(const Value *V, CaptureTracker *Tracker);
 } // end namespace llvm
 
 #endif