Clamp down on sinking of lots of instructions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@45841 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/MachineSink.cpp b/lib/CodeGen/MachineSink.cpp
index c832f0a..b83d844 100644
--- a/lib/CodeGen/MachineSink.cpp
+++ b/lib/CodeGen/MachineSink.cpp
@@ -130,6 +130,15 @@
/// SinkInstruction - Determine whether it is safe to sink the specified machine
/// instruction out of its current block into a successor.
bool MachineSinking::SinkInstruction(MachineInstr *MI) {
+ const TargetInstrDesc &TID = MI->getDesc();
+
+ // Ignore stuff that we obviously can't sink.
+ if (TID.mayStore() || TID.isCall() || TID.isReturn() || TID.isBranch())
+ return false;
+
+ if (TID.mayLoad())
+ return false;
+
// Don't sink things with side-effects we don't understand.
if (TII->hasUnmodelledSideEffects(MI))
return false;