Lift the speculation visitor above all the helpers that are targeted at

[oota-llvm.git] / lib / Transforms / Scalar / CorrelatedValuePropagation.cpp

diff --git a/lib/Transforms/Scalar/CorrelatedValuePropagation.cpp b/lib/Transforms/Scalar/CorrelatedValuePropagation.cpp
index ffe499135ebdd97bfc1bfaf493e2b3a014af4f67..3ec6f3dcc31b0d98f377acd8ce4e63b08b98ab33 100644 (file)
--- a/lib/Transforms/Scalar/CorrelatedValuePropagation.cpp
+++ b/lib/Transforms/Scalar/CorrelatedValuePropagation.cpp
@@ -28,6 +28,7 @@ STATISTIC(NumPhis,      "Number of phis propagated");
 STATISTIC(NumSelects,   "Number of selects propagated");
 STATISTIC(NumMemAccess, "Number of memory access targets propagated");
 STATISTIC(NumCmps,      "Number of comparisons propagated");
+STATISTIC(NumDeadCases, "Number of switch cases removed");
 
 namespace {
   class CorrelatedValuePropagation : public FunctionPass {
@@ -111,7 +112,8 @@ bool CorrelatedValuePropagation::processPHI(PHINode *P) {
     Changed = true;
   }
 
-  ++NumPhis;
+  if (Changed)
+    ++NumPhis;
 
   return Changed;
 }
@@ -197,7 +199,7 @@ bool CorrelatedValuePropagation::processSwitch(SwitchInst *SI) {
   // Analyse each switch case in turn.  This is done in reverse order so that
   // removing a case doesn't cause trouble for the iteration.
   bool Changed = false;
-  for (SwitchInst::CaseIt CI = SI->caseEnd(), CE = SI->caseBegin(); CI-- != CE;
+  for (SwitchInst::CaseIt CI = SI->case_end(), CE = SI->case_begin(); CI-- != CE;
        ) {
     ConstantInt *Case = CI.getCaseValue();
 
@@ -233,12 +235,19 @@ bool CorrelatedValuePropagation::processSwitch(SwitchInst *SI) {
       // This case never fires - remove it.
       CI.getCaseSuccessor()->removePredecessor(BB);
       SI->removeCase(CI); // Does not invalidate the iterator.
+
+      // The condition can be modified by removePredecessor's PHI simplification
+      // logic.
+      Cond = SI->getCondition();
+
+      ++NumDeadCases;
       Changed = true;
     } else if (State == LazyValueInfo::True) {
       // This case always fires.  Arrange for the switch to be turned into an
       // unconditional branch by replacing the switch condition with the case
       // value.
       SI->setCondition(Case);
+      NumDeadCases += SI->getNumCases();
       Changed = true;
       break;
     }