Delete dead PHI machine instructions. These can be created due to type
legalization even when the IR-level optimizer has removed dead phis, such
as when the high half of an i64 value is unused on a 32-bit target.
I had to adjust a few test cases that had dead phis.
This is a partial fix for Radar 7627077.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95816 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/DeadMachineInstructionElim.cpp b/lib/CodeGen/DeadMachineInstructionElim.cpp
index b0cb24d..6e01e59 100644
--- a/lib/CodeGen/DeadMachineInstructionElim.cpp
+++ b/lib/CodeGen/DeadMachineInstructionElim.cpp
@@ -55,7 +55,7 @@
bool DeadMachineInstructionElim::isDead(const MachineInstr *MI) const {
// Don't delete instructions with side effects.
bool SawStore = false;
- if (!MI->isSafeToMove(TII, SawStore, 0))
+ if (!MI->isSafeToMove(TII, SawStore, 0) && !MI->isPHI())
return false;
// Examine each operand.