Add comments for missed opportunities.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@100610 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/MachineLICM.cpp b/lib/CodeGen/MachineLICM.cpp
index 72f7d45..0edd44b 100644
--- a/lib/CodeGen/MachineLICM.cpp
+++ b/lib/CodeGen/MachineLICM.cpp
@@ -247,6 +247,8 @@
if (!CurLoop->contains(BB))
continue;
// Conservatively treat live-in's as an external def.
+ // FIXME: That means a reload that's reused into a fallthrough block
+ // will not be LICM'ed.
for (MachineBasicBlock::const_livein_iterator I = BB->livein_begin(),
E = BB->livein_end(); I != E; ++I) {
unsigned Reg = *I;
@@ -282,7 +284,8 @@
}
}
- // FIXME: Only consider reloads for now.
+ // FIXME: Only consider reloads for now. We should be able to handle
+ // remat which does not have register operands.
bool SkipCheck = false;
int FI;
if (SeenDef && !RuledOut) {