Adding collection of IV chains to LSR.

[oota-llvm.git] / lib / Analysis / CaptureTracking.cpp

diff --git a/lib/Analysis/CaptureTracking.cpp b/lib/Analysis/CaptureTracking.cpp
index 9be00971dc6796e642ca9eb5b9c8deed6967d14b..68993ead2c85539d32738946043335210d40c894 100644 (file)
--- a/lib/Analysis/CaptureTracking.cpp
+++ b/lib/Analysis/CaptureTracking.cpp
@@ -19,6 +19,8 @@
 #include "llvm/Analysis/CaptureTracking.h"
 using namespace llvm;
 
+CaptureTracker::~CaptureTracker() {}
+
 namespace {
   struct SimpleCaptureTracker : public CaptureTracker {
     explicit SimpleCaptureTracker(bool ReturnCaptures)
@@ -28,8 +30,8 @@ namespace {
 
     bool shouldExplore(Use *U) { return true; }
 
-    bool captured(Instruction *I) {
-      if (isa<ReturnInst>(I) && !ReturnCaptures)
+    bool captured(Use *U) {
+      if (isa<ReturnInst>(U->getUser()) && !ReturnCaptures)
        return false;
 
       Captured = true;
@@ -51,6 +53,9 @@ namespace {
 /// counts as capturing it or not.
 bool llvm::PointerMayBeCaptured(const Value *V,
                                 bool ReturnCaptures, bool StoreCaptures) {
+  assert(!isa<GlobalValue>(V) &&
+         "It doesn't make sense to ask whether a global is captured.");
+
   // TODO: If StoreCaptures is not true, we could do Fancy analysis
   // to determine whether this store is not actually an escape point.
   // In that case, BasicAliasAnalysis should be updated as well to
@@ -112,7 +117,7 @@ void llvm::PointerMayBeCaptured(const Value *V, CaptureTracker *Tracker) {
       for (CallSite::arg_iterator A = B; A != E; ++A)
         if (A->get() == V && !CS.doesNotCapture(A - B))
           // The parameter is not marked 'nocapture' - captured.
-          if (Tracker->captured(I))
+          if (Tracker->captured(U))
             return;
       break;
     }
@@ -125,7 +130,7 @@ void llvm::PointerMayBeCaptured(const Value *V, CaptureTracker *Tracker) {
     case Instruction::Store:
       if (V == I->getOperand(0))
         // Stored the pointer - conservatively assume it may be captured.
-        if (Tracker->captured(I))
+        if (Tracker->captured(U))
           return;
       // Storing to the pointee does not cause the pointer to be captured.
       break;
@@ -153,12 +158,12 @@ void llvm::PointerMayBeCaptured(const Value *V, CaptureTracker *Tracker) {
             break;
       // Otherwise, be conservative. There are crazy ways to capture pointers
       // using comparisons.
-      if (Tracker->captured(I))
+      if (Tracker->captured(U))
         return;
       break;
     default:
       // Something else - be conservative and say it is captured.
-      if (Tracker->captured(I))
+      if (Tracker->captured(U))
         return;
       break;
     }