r64073 commit message is lost. Here it is:

Right now if the coalesced copy def is dead and its src is a kill, and that
there are now other uses within the live range, the coalescer would mark the
def of the source register as dead. But it should also check if there are
other kills which means the value has other uses not in the live range.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@64075 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 4 insertions, 3 deletions

diff --git a/lib/CodeGen/SimpleRegisterCoalescing.cpp b/lib/CodeGen/SimpleRegisterCoalescing.cpp
index 75389a412a..a7d5d0075d 100644
--- a/lib/CodeGen/SimpleRegisterCoalescing.cpp
+++ b/lib/CodeGen/SimpleRegisterCoalescing.cpp
@@ -867,11 +867,12 @@ SimpleRegisterCoalescing::ShortenDeadCopySrcLiveRange(LiveInterval &li,
   if (LR->valno->def == RemoveStart) {
     // If the def MI defines the val# and this copy is the only kill of the
     // val#, then propagate the dead marker.
-    if (li.isOnlyKill(LR->valno, RemoveEnd)) {
+    if (!li.isOnlyKill(LR->valno, RemoveEnd))
+      li.removeKill(LR->valno, RemoveEnd);
+    else {
       PropagateDeadness(li, CopyMI, RemoveStart, li_, tri_);
       ++numDeadValNo;
-    } else
-      li.removeKill(LR->valno, RemoveEnd);
+    }
   }
 
   removeRange(li, RemoveStart, LR->end, li_, tri_);