If the 2addr instruction has other kills, don't move it below any other uses since we don't want to extend other live ranges.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@144772 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/TwoAddressInstructionPass.cpp b/lib/CodeGen/TwoAddressInstructionPass.cpp
index 3e9a0e4..7a0fcb5 100644
--- a/lib/CodeGen/TwoAddressInstructionPass.cpp
+++ b/lib/CodeGen/TwoAddressInstructionPass.cpp
@@ -933,6 +933,7 @@
return false;
SmallSet<unsigned, 2> Uses;
+ SmallSet<unsigned, 2> Kills;
SmallSet<unsigned, 2> Defs;
for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
const MachineOperand &MO = MI->getOperand(i);
@@ -943,8 +944,11 @@
continue;
if (MO.isDef())
Defs.insert(MOReg);
- else
+ else {
Uses.insert(MOReg);
+ if (MO.isKill() && MOReg != Reg)
+ Kills.insert(MOReg);
+ }
}
// Move the copies connected to MI down as well.
@@ -991,7 +995,8 @@
} else {
if (Defs.count(MOReg))
return false;
- if (MOReg != Reg && MO.isKill() && Uses.count(MOReg))
+ if (MOReg != Reg &&
+ ((MO.isKill() && Uses.count(MOReg)) || Kills.count(MOReg)))
// Don't want to extend other live ranges and update kills.
return false;
}