#ifndef LLVM_ANALYSIS_CAPTURETRACKING_H
#define LLVM_ANALYSIS_CAPTURETRACKING_H
-namespace llvm {
- class Value;
+#include "llvm/Analysis/AliasAnalysis.h"
+#include "llvm/IR/Constants.h"
+#include "llvm/IR/Instructions.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
/// specifies whether returning the value (or part of it) from the function
- /// counts as capturing it or not. The boolean StoreCaptures specified whether
- /// storing the value (or part of it) into memory anywhere automatically
- /// counts as capturing it or not.
+ /// counts as capturing it or not. The boolean StoreCaptures specified
+ /// whether storing the value (or part of it) into memory anywhere
+ /// automatically counts as capturing it or not.
bool PointerMayBeCaptured(const Value *V,
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);
+
+ /// 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