Compile time improvements to VirtRegRewriter.
This change to VirtRegRewriter::addMBBLiveIns adds live-in registers for each
MachineBasicBlock's LiveIns set without isLiveIn checks as they are being added
because doing so is expensive. After all live-in registers are added, the LiveIn
vectors are sorted and uniqued.
llvm-svn: 238008
diff --git a/llvm/lib/CodeGen/VirtRegMap.cpp b/llvm/lib/CodeGen/VirtRegMap.cpp
index d9adfdf..9fb1b5b 100644
--- a/llvm/lib/CodeGen/VirtRegMap.cpp
+++ b/llvm/lib/CodeGen/VirtRegMap.cpp
@@ -264,8 +264,7 @@
if ((SubRegLaneMask & S.LaneMask) == 0)
continue;
for (unsigned i = 0, e = LiveIn.size(); i != e; ++i) {
- if (!LiveIn[i]->isLiveIn(SubReg))
- LiveIn[i]->addLiveIn(SubReg);
+ LiveIn[i]->addLiveIn(SubReg);
}
}
LiveIn.clear();
@@ -277,12 +276,16 @@
if (!Indexes->findLiveInMBBs(Seg.start, Seg.end, LiveIn))
continue;
for (unsigned i = 0, e = LiveIn.size(); i != e; ++i)
- if (!LiveIn[i]->isLiveIn(PhysReg))
- LiveIn[i]->addLiveIn(PhysReg);
+ LiveIn[i]->addLiveIn(PhysReg);
LiveIn.clear();
}
}
}
+
+ // Sort and unique MBB LiveIns as we've not checked if SubReg/PhysReg were in
+ // each MBB's LiveIns set before calling addLiveIn on them.
+ for (MachineBasicBlock &MBB : *MF)
+ MBB.sortUniqueLiveIns();
}
void VirtRegRewriter::rewrite() {