Revert r153516: "Invalidate liveness in Thumb2ITBlockPass."

Revert r153519: "ARMLoadStoreOptimizer invalidates register liveness."

These patches caused miscompilations in povray by turning off branch
folding's updating of live-in lists.

It turns out the the late scheduler depends on the live-in lists, even
if it doesn't need correct kill flags.

<rdar://problem/11139228>

llvm-svn: 153593

1 files changed, 0 insertions, 4 deletions

diff --git a/llvm/lib/Target/ARM/Thumb2ITBlockPass.cpp b/llvm/lib/Target/ARM/Thumb2ITBlockPass.cpp
index e2166ffc322..ecb4c2f0e5d 100644
--- a/llvm/lib/Target/ARM/Thumb2ITBlockPass.cpp
+++ b/llvm/lib/Target/ARM/Thumb2ITBlockPass.cpp
@@ -15,7 +15,6 @@
 #include "llvm/CodeGen/MachineInstrBuilder.h"
 #include "llvm/CodeGen/MachineInstrBundle.h"
 #include "llvm/CodeGen/MachineFunctionPass.h"
-#include "llvm/CodeGen/MachineRegisterInfo.h"
 #include "llvm/ADT/SmallSet.h"
 #include "llvm/ADT/Statistic.h"
 using namespace llvm;
@@ -259,9 +258,6 @@ bool Thumb2ITBlockPass::runOnMachineFunction(MachineFunction &Fn) {
   if (!AFI->isThumbFunction())
     return false;
 
-  // IT block insertion invalidates accurate register liveness.
-  Fn.getRegInfo().invalidateLiveness();
-
   bool Modified = false;
   for (MachineFunction::iterator MFI = Fn.begin(), E = Fn.end(); MFI != E; ) {
     MachineBasicBlock &MBB = *MFI;