Fix a CPSR liveness tracking bug introduced when I converted IT block to bundle.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@146805 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 7 insertions, 4 deletions

diff --git a/lib/Target/ARM/Thumb2SizeReduction.cpp b/lib/Target/ARM/Thumb2SizeReduction.cpp
index e2062882e2..4abff28f02 100644
--- a/lib/Target/ARM/Thumb2SizeReduction.cpp
+++ b/lib/Target/ARM/Thumb2SizeReduction.cpp
@@ -880,14 +880,17 @@ bool Thumb2SizeReduce::ReduceMBB(MachineBasicBlock &MBB) {
     }
 
   ProcessNext:
-    if (LiveCPSR &&
-        NextMII != E && MI->isInsideBundle() && !NextMII->isInsideBundle() &&
-        BundleMI->killsRegister(ARM::CPSR))
+    if (NextMII != E && MI->isInsideBundle() && !NextMII->isInsideBundle()) {
       // FIXME: Since post-ra scheduler operates on bundles, the CPSR kill
       // marker is only on the BUNDLE instruction. Process the BUNDLE
       // instruction as we finish with the bundled instruction to work around
       // the inconsistency.
-      LiveCPSR = false;
+      if (BundleMI->killsRegister(ARM::CPSR))
+        LiveCPSR = false;
+      MachineOperand *MO = BundleMI->findRegisterDefOperand(ARM::CPSR);
+      if (MO && !MO->isDead())
+        LiveCPSR = true;
+    }
 
     bool DefCPSR = false;
     LiveCPSR = UpdateCPSRDef(*MI, LiveCPSR, DefCPSR);