From 3662f0d492533435c30969118fd025f6bed46654 Mon Sep 17 00:00:00 2001
From: Jakob Stoklund Olesen <stoklund@2pi.dk>
Date: Sat, 19 May 2012 05:25:53 +0000
Subject: [PATCH] Immediately erase trivially useless copies.
There is no need for these instructions to stick around since they are
known to be not dead.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@157102 91177308-0d34-0410-b5e6-96231b3b80d8
---
lib/CodeGen/RegisterCoalescer.cpp | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/lib/CodeGen/RegisterCoalescer.cpp b/lib/CodeGen/RegisterCoalescer.cpp
index 84fd590f268..0dbc7b6c659 100644
--- a/lib/CodeGen/RegisterCoalescer.cpp
+++ b/lib/CodeGen/RegisterCoalescer.cpp
@@ -1070,15 +1070,17 @@ bool RegisterCoalescer::joinCopy(MachineInstr *CopyMI, bool &Again) {
// If they are already joined we continue.
if (CP.getSrcReg() == CP.getDstReg()) {
- markAsJoined(CopyMI);
DEBUG(dbgs() << "\tCopy already coalesced.\n");
+ LIS->RemoveMachineInstrFromMaps(CopyMI);
+ CopyMI->eraseFromParent();
return false; // Not coalescable.
}
// Eliminate undefs.
if (!CP.isPhys() && eliminateUndefCopy(CopyMI, CP)) {
- markAsJoined(CopyMI);
DEBUG(dbgs() << "\tEliminated copy of <undef> value.\n");
+ LIS->RemoveMachineInstrFromMaps(CopyMI);
+ CopyMI->eraseFromParent();
return false; // Not coalescable.
}