Handle overlapping regunit intervals in LiveIntervals::addKillFlags().

We will soon allow virtual register live ranges to overlap regunit live
ranges when the physreg is defined as a copy of the virtreg:

  %EAX = COPY %vreg5
  FOO %vreg5
  BAR %EAX<kill>

There is no real interference since %vreg5 and %EAX have the same value
where they overlap.

This patch prevents addKillFlags from adding virtreg kill flags to FOO
where the assigned physreg is overlapping the virtual register live
range.

llvm-svn: 163335

1 files changed, 1 insertions, 1 deletions

diff --git a/llvm/lib/CodeGen/VirtRegMap.cpp b/llvm/lib/CodeGen/VirtRegMap.cpp
index a1cac7c5b2a..6343e8a3529 100644
--- a/llvm/lib/CodeGen/VirtRegMap.cpp
+++ b/llvm/lib/CodeGen/VirtRegMap.cpp
@@ -200,7 +200,7 @@ bool VirtRegRewriter::runOnMachineFunction(MachineFunction &fn) {
   DEBUG(VRM->dump());
 
   // Add kill flags while we still have virtual registers.
-  LIS->addKillFlags();
+  LIS->addKillFlags(VRM);
 
   // Live-in lists on basic blocks are required for physregs.
   addMBBLiveIns();