Add a temporary command line option to verify machine code after each spill or
split.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@117597 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/InlineSpiller.cpp b/lib/CodeGen/InlineSpiller.cpp
index e938135..73980f3 100644
--- a/lib/CodeGen/InlineSpiller.cpp
+++ b/lib/CodeGen/InlineSpiller.cpp
@@ -25,11 +25,15 @@
 #include "llvm/CodeGen/MachineRegisterInfo.h"
 #include "llvm/Target/TargetMachine.h"
 #include "llvm/Target/TargetInstrInfo.h"
+#include "llvm/Support/CommandLine.h"
 #include "llvm/Support/Debug.h"
 #include "llvm/Support/raw_ostream.h"
 
 using namespace llvm;
 
+static cl::opt<bool>
+VerifySpills("verify-spills", cl::desc("Verify after each spill/split"));
+
 namespace {
 class InlineSpiller : public Spiller {
   MachineFunctionPass &pass_;
@@ -337,6 +341,8 @@
                           SmallVectorImpl<LiveInterval*> &spillIs) {
   LiveRangeEdit edit(*li, newIntervals, spillIs);
   spill(edit);
+  if (VerifySpills)
+    mf_.verify(&pass_);
 }
 
 void InlineSpiller::spill(LiveRangeEdit &edit) {