commit e3d3b88cb985c6a1d975463a00a57925b0ed64d1
author Matthias Braun <matze@braunis.de> Wed Dec 10 01:12:30 2014 +0000
committer Matthias Braun <matze@braunis.de> Wed Dec 10 01:12:30 2014 +0000
tree a8829432b9cf5825791b0ee792d740523c4d01a9
parent e5f861b781e1e434f2e58f434c7e89d5bb2e7840

Add a flag to enable/disable subregister liveness.

llvm-svn: 223884

llvm/lib/CodeGen/LiveRangeCalc.cpp

diff --git a/llvm/lib/CodeGen/LiveRangeCalc.cpp b/llvm/lib/CodeGen/LiveRangeCalc.cpp
index 4433fb1..daa1ee0 100644
--- a/llvm/lib/CodeGen/LiveRangeCalc.cpp
+++ b/llvm/lib/CodeGen/LiveRangeCalc.cpp
@@ -55,7 +55,7 @@
     const MachineInstr *MI = MO.getParent();
     SlotIndex Idx = getDefIndex(*Indexes, *MI, MO.isEarlyClobber());
     unsigned SubReg = MO.getSubReg();
-    if (SubReg != 0 || LI.hasSubRanges()) {
+    if (LI.hasSubRanges() || (SubReg != 0 && MRI->tracksSubRegLiveness())) {
       unsigned Mask = SubReg != 0 ? TRI.getSubRegIndexLaneMask(SubReg)
                                   : MRI->getMaxLaneMaskForVReg(Reg);
 
@@ -179,7 +179,8 @@
       continue;
     SlotIndex Idx = getUseIndex(*Indexes, MO);
     unsigned SubReg = MO.getSubReg();
-    if (MO.isUse() && (LI.hasSubRanges() || SubReg != 0)) {
+    if (MO.isUse() && (LI.hasSubRanges() ||
+                       (MRI->tracksSubRegLiveness() && SubReg != 0))) {
       unsigned Mask = SubReg != 0
         ? TRI.getSubRegIndexLaneMask(SubReg)
         : Mask = MRI->getMaxLaneMaskForVReg(Reg);