Fix PR10104 by adding a bounds check on a vector element access check. It was

[oota-llvm.git] / lib / CodeGen / PHIElimination.cpp

diff --git a/lib/CodeGen/PHIElimination.cpp b/lib/CodeGen/PHIElimination.cpp
index f59e4f1aa3b73b2d3747721810264708a058b08b..af65f13bf065eb202152145480a6bf8db7480724 100644 (file)
--- a/lib/CodeGen/PHIElimination.cpp
+++ b/lib/CodeGen/PHIElimination.cpp
@@ -28,12 +28,17 @@
 #include "llvm/ADT/SmallPtrSet.h"
 #include "llvm/ADT/STLExtras.h"
 #include "llvm/ADT/Statistic.h"
+#include "llvm/Support/CommandLine.h"
 #include "llvm/Support/Compiler.h"
 #include "llvm/Support/Debug.h"
 #include <algorithm>
-#include <map>
 using namespace llvm;
 
+static cl::opt<bool>
+DisableEdgeSplitting("disable-phi-elim-edge-splitting", cl::init(false),
+                     cl::Hidden, cl::desc("Disable critical edge splitting "
+                                          "during PHI elimination"));
+
 namespace {
   class PHIElimination : public MachineFunctionPass {
     MachineRegisterInfo *MRI; // Machine register information
@@ -105,10 +110,12 @@ bool PHIElimination::runOnMachineFunction(MachineFunction &MF) {
   bool Changed = false;
 
   // Split critical edges to help the coalescer
-  if (LiveVariables *LV = getAnalysisIfAvailable<LiveVariables>()) {
-    MachineLoopInfo *MLI = getAnalysisIfAvailable<MachineLoopInfo>();
-    for (MachineFunction::iterator I = MF.begin(), E = MF.end(); I != E; ++I)
-      Changed |= SplitPHIEdges(MF, *I, *LV, MLI);
+  if (!DisableEdgeSplitting) {
+    if (LiveVariables *LV = getAnalysisIfAvailable<LiveVariables>()) {
+      MachineLoopInfo *MLI = getAnalysisIfAvailable<MachineLoopInfo>();
+      for (MachineFunction::iterator I = MF.begin(), E = MF.end(); I != E; ++I)
+        Changed |= SplitPHIEdges(MF, *I, *LV, MLI);
+    }
   }
 
   // Populate VRegPHIUseCount
@@ -393,9 +400,9 @@ void PHIElimination::analyzePHINodes(const MachineFunction& MF) {
 }
 
 bool PHIElimination::SplitPHIEdges(MachineFunction &MF,
-                                         MachineBasicBlock &MBB,
-                                         LiveVariables &LV,
-                                         MachineLoopInfo *MLI) {
+                                   MachineBasicBlock &MBB,
+                                   LiveVariables &LV,
+                                   MachineLoopInfo *MLI) {
   if (MBB.empty() || !MBB.front().isPHI() || MBB.isLandingPad())
     return false;   // Quick exit for basic blocks without PHIs.
 
@@ -423,5 +430,5 @@ bool PHIElimination::SplitPHIEdges(MachineFunction &MF,
       }
     }
   }
-  return true;
+  return Changed;
 }